Oblique Fissure: An anatomical groove dividing the upper and lower lobes of both lungs.
Surface Marking: Reference points on the thoracic wall indicating internal structures.
Lungs: Paired respiratory organs in the thoracic cavity for gas exchange.
Ribs and Costal Cartilage: Structures forming the thoracic cage and surface landmarks.
T3 Vertebra: Third thoracic vertebra, used as a posterior reference point.
Clinical Significance: Knowledge of fissure surface markings guides auscultation, percussion, and thoracic procedures.
Chapter: Respiratory Anatomy
Topic: Lobar Anatomy of Lungs
Subtopic: Oblique Fissure Surface Markings
Lead Question 2012: Surface marking of the oblique fissure of the lung include all except:
a) T3
b) 5th rib
c) 7th rib
d) 6th costal cartilage
Answer: a) T3
Explanation: The oblique fissure of the lungs begins posteriorly at the level of T2 vertebra on the right and T3–T4 vertebra on the left, descending anteriorly to the 6th rib midclavicular line. T3 alone is not a consistent surface landmark. Accurate surface marking is crucial for auscultation, thoracentesis, and imaging interpretation.
1. The oblique fissure separates which lobes of the right lung?
a) Upper and middle lobes
b) Upper and lower lobes
c) Middle and lower lobes
d) Upper and accessory lobes
Answer: b) Upper and lower lobes
Explanation: The oblique fissure divides the upper and lower lobes of the right lung. On the left, it separates the upper and lower lobes as well. Understanding fissure anatomy is important in interpreting X-rays, CT scans, and planning surgical procedures.
2. Posteriorly, the oblique fissure of the left lung corresponds to which vertebra?
a) T1
b) T3–T4
c) T5
d) T6
Answer: b) T3–T4
Explanation: The left oblique fissure begins posteriorly around T3–T4 vertebra and slopes downward to the 6th rib anteriorly. Clinically, this helps localize pulmonary lesions and guide thoracic procedures.
3. Anteriorly, the oblique fissure reaches which rib in midclavicular line?
a) 4th rib
b) 5th rib
c) 6th rib
d) 7th rib
Answer: c) 6th rib
Explanation: The oblique fissure extends anteriorly to the 6th rib in the midclavicular line. This landmark is used during percussion and auscultation of lung fields for clinical assessment of lobar pathology.
4. Which fissure is horizontal in the right lung?
a) Oblique
b) Horizontal
c) Accessory
d) None
Answer: b) Horizontal
Explanation: The right lung has a horizontal fissure that separates the upper and middle lobes, in addition to the oblique fissure. This is clinically important during imaging and surgical interventions.
5. Surface marking of horizontal fissure at midaxillary line corresponds to:
a) 4th rib
b) 5th rib
c) 6th rib
d) 7th rib
Answer: b) 5th rib
Explanation: The horizontal fissure passes from the 4th costal cartilage anteriorly to the 5th rib midaxillary line, separating upper and middle lobes of the right lung. Accurate surface marking is key for thoracentesis.
6. The oblique fissure crosses which costal cartilage anteriorly?
a) 4th
b) 5th
c) 6th
d) 7th
Answer: c) 6th
Explanation: The anterior end of the oblique fissure aligns with the 6th rib/costal cartilage in the midclavicular line. This is critical for identifying lobar boundaries in clinical examination and radiography.
7. Which fissure is absent in the left lung?
a) Oblique
b) Horizontal
c) Both
d) Accessory
Answer: b) Horizontal
Explanation: The left lung has no horizontal fissure. It only has an oblique fissure dividing upper and lower lobes. This anatomical difference is important during imaging and surgery.
8. Oblique fissure aids in clinical assessment of:
a) Heart murmurs
b) Lobar pneumonia
c) Diaphragmatic hernia
d) Mediastinal shift
Answer: b) Lobar pneumonia
Explanation: Oblique fissure separates lobes; identification of lobar boundaries helps in diagnosing localized pneumonia or effusions, guiding auscultation, percussion, and imaging interpretation.
9. Posteriorly, the right oblique fissure starts at which vertebra?
a) T2
b) T3
c) T4
d) T5
Answer: b) T3
Explanation: The right oblique fissure starts posteriorly at T3 vertebra and descends to the 6th rib anteriorly. This is a critical surface landmark for thoracic procedures and clinical examination.
10. The oblique fissure crosses which rib at the midaxillary line?
a) 4th
b) 5th
c) 6th
d) 7th
Answer: b) 5th rib
Explanation: At the midaxillary line, the oblique fissure passes approximately along the 5th rib, separating upper and lower lobes. Recognizing this landmark aids in thoracic auscultation and safe needle placement for procedures like pleural tap.
Sympathetic Nervous System: Part of the autonomic nervous system responsible for 'fight or flight' responses.
Cardiac Sympathetic Supply: Nerves arising from thoracic spinal segments innervating the heart, increasing heart rate and contractility.
Spinal Segments: Sections of the spinal cord from which sympathetic fibers emerge (T1–L2).
SA Node: Sinoatrial node, pacemaker of the heart, receives sympathetic and parasympathetic innervation.
AV Node: Atrioventricular node, conduction relay, also influenced by autonomic inputs.
Thoracic Sympathetic Chain: Series of ganglia along thoracic vertebrae transmitting sympathetic fibers to organs including the heart.
Chapter: Cardiovascular Physiology
Topic: Autonomic Nervous Supply of Heart
Subtopic: Sympathetic Innervation
Lead Question 2012: Sympathetic supply to the heart arises from which of the following spinal segments?
a) T1 to T5
b) T2 to T6
c) T3 to T7
d) T4 to T8
Answer: a) T1 to T5
Explanation: Cardiac sympathetic fibers arise from the thoracic spinal segments T1 to T5. These preganglionic fibers synapse in the sympathetic chain and postganglionic fibers reach the SA node, AV node, and coronary vessels. They increase heart rate, contractility, and conduction velocity. Understanding this is crucial in autonomic cardiac physiology and clinical conditions like referred cardiac pain.
1. Which part of the autonomic nervous system increases heart rate?
a) Parasympathetic
b) Sympathetic
c) Enteric
d) Somatic
Answer: b) Sympathetic
Explanation: Sympathetic stimulation increases heart rate, contractility, and conduction through SA and AV nodes. Parasympathetic (vagal) stimulation decreases heart rate. This balance is essential for cardiac homeostasis and is clinically important in arrhythmias and heart failure.
2. Preganglionic sympathetic fibers to the heart synapse in which ganglia?
a) Cervical ganglia
b) Thoracic sympathetic chain
c) Dorsal root ganglia
d) Celiac ganglia
Answer: b) Thoracic sympathetic chain
Explanation: Preganglionic fibers from T1–T5 synapse in the thoracic sympathetic chain. Postganglionic fibers then reach cardiac structures. This pathway is clinically significant for cardiac sympathectomy and management of arrhythmias.
3. Sympathetic stimulation affects which part of the heart first?
a) SA node
b) AV node
c) Ventricular myocardium
d) Aorta
Answer: a) SA node
Explanation: Sympathetic fibers primarily influence the SA node, increasing heart rate. AV node conduction and ventricular contractility are also enhanced, demonstrating the widespread effect of sympathetic innervation on cardiac function.
4. Referred cardiac pain is transmitted through which spinal segments?
a) T1–T5
b) C3–C5
c) L1–L3
d) S1–S3
Answer: a) T1–T5
Explanation: Sympathetic afferents from the heart enter spinal cord segments T1–T5, producing referred pain in the chest and medial arm during myocardial ischemia. Knowledge of this pathway aids in diagnosing angina or myocardial infarction.
5. Which neurotransmitter is released by postganglionic sympathetic fibers at the heart?
a) Acetylcholine
b) Norepinephrine
c) Dopamine
d) Serotonin
Answer: b) Norepinephrine
Explanation: Postganglionic sympathetic fibers release norepinephrine, which binds to beta-1 adrenergic receptors, increasing heart rate and contractility. Pharmacologic modulation of this pathway is important in heart failure and arrhythmia management.
6. Sympathetic cardiac nerves also innervate which coronary structures?
a) Coronary arteries
b) Pulmonary veins
c) Aorta only
d) SA node exclusively
Answer: a) Coronary arteries
Explanation: Sympathetic nerves innervate coronary vessels, causing vasodilation via beta-2 receptors during increased cardiac activity, ensuring adequate myocardial perfusion during stress or exercise.
7. Beta-1 adrenergic receptors are predominantly located on:
a) SA and AV nodes
b) Smooth muscle of arteries
c) Lung alveoli
d) Skeletal muscle
Answer: a) SA and AV nodes
Explanation: Beta-1 receptors are located on nodal tissue and ventricular myocardium, mediating sympathetic effects like increased heart rate and conduction velocity. Beta-blockers act here to treat tachyarrhythmias and hypertension.
8. Cardiac sympathectomy may be performed to treat:
a) Refractory angina
b) GERD
c) Asthma
d) Liver cirrhosis
Answer: a) Refractory angina
Explanation: Cardiac sympathectomy reduces sympathetic input, lowering heart rate and oxygen demand in severe angina. T1–T5 segments are targeted to interrupt sympathetic supply while preserving parasympathetic tone.
9. Which spinal levels contribute to sympathetic innervation of both SA and AV nodes?
a) T1–T5
b) C1–C4
c) L1–L3
d) T6–T10
Answer: a) T1–T5
Explanation: Preganglionic fibers from T1–T5 synapse in the cervical and upper thoracic ganglia. Postganglionic fibers innervate both SA and AV nodes, coordinating cardiac rate and conduction, essential knowledge for cardiology exams.
10. Increased sympathetic activity to the heart results in:
a) Tachycardia and increased contractility
b) Bradycardia and decreased contractility
c) Vasodilation of systemic veins
d) No change in cardiac function
Answer: a) Tachycardia and increased contractility
Explanation: Sympathetic activation increases SA node firing rate, AV conduction, and myocardial contractility through norepinephrine action on beta-1 receptors. This response supports cardiac output during stress and is a core concept in autonomic cardiac physiology.
Transverse Sinus: A pericardial space posterior to the aorta and pulmonary trunk, allowing surgical access during cardiac procedures.
Pericardial Sinuses: Spaces within the pericardial sac, including transverse and oblique sinuses.
Right Atrium: Receives deoxygenated blood from systemic veins.
Left Atrium: Receives oxygenated blood from pulmonary veins.
Aorta: Main artery leaving the left ventricle, distributing oxygenated blood to the body.
Pulmonary Artery: Artery carrying deoxygenated blood from the right ventricle to the lungs.
Chapter: Heart Anatomy
Topic: Pericardial Sinuses
Subtopic: Transverse Sinus Location
Lead Question 2012: The transverse sinus is present posterior to which structures?
a) Right atrium
b) Left atrium
c) Upper pulmonary artery
d) Aorta
Answer: d) Aorta
Explanation: The transverse pericardial sinus lies posterior to the ascending aorta and pulmonary trunk, and anterior to the superior vena cava. It is a critical landmark during cardiac surgery, allowing surgeons to pass ligatures around the great arteries. It is not located behind the atria or pulmonary artery itself.
1. Which pericardial sinus is located posterior to the left atrium?
a) Transverse sinus
b) Oblique sinus
c) Coronary sinus
d) Superior sinus
Answer: b) Oblique sinus
Explanation: The oblique pericardial sinus is a blind recess posterior to the left atrium, bounded by the pulmonary veins and inferior vena cava. Understanding sinus locations is important during pericardial fluid drainage or cardiac surgery.
2. The transverse sinus is clinically important because:
a) It houses the SA node
b) Surgeons can pass ligatures around great arteries
c) It drains coronary veins
d) It surrounds the atrioventricular valves
Answer: b) Surgeons can pass ligatures around great arteries
Explanation: The transverse sinus lies between the arterial and venous ends of the heart, allowing safe passage of ligatures around the aorta and pulmonary artery during procedures such as cardiopulmonary bypass. It does not house the SA node or valves.
3. The transverse sinus is bounded anteriorly by:
a) Superior vena cava
b) Pulmonary veins
c) Ascending aorta and pulmonary trunk
d) Inferior vena cava
Answer: c) Ascending aorta and pulmonary trunk
Explanation: The transverse sinus lies posterior to the aorta and pulmonary trunk, and anterior to the superior vena cava. This anatomical position is significant during procedures like clamping or bypass.
4. Which structure lies posterior to the transverse sinus?
a) Aorta
b) Superior vena cava
c) Left atrium
d) Pulmonary artery
Answer: c) Left atrium
Explanation: The transverse sinus separates the arterial trunks (aorta and pulmonary trunk) anteriorly from the venous structures and left atrium posteriorly. Surgeons use this space to manipulate vessels during cardiac procedures.
5. The coronary sinus drains into which chamber of the heart?
a) Right atrium
b) Left atrium
c) Right ventricle
d) Left ventricle
Answer: a) Right atrium
Explanation: The coronary sinus is located in the posterior atrioventricular groove and drains deoxygenated blood from the myocardium into the right atrium. Its position is close to the oblique sinus but not the transverse sinus.
6. In cardiac surgery, clamping the aorta can be facilitated using which sinus?
a) Oblique sinus
b) Transverse sinus
c) Coronary sinus
d) Superior sinus
Answer: b) Transverse sinus
Explanation: The transverse sinus lies behind the aorta and pulmonary trunk. Surgeons pass tapes or clamps through this space to isolate these arteries during cardiopulmonary bypass, making it a key anatomical landmark.
7. Which sinus is a blind-ended recess located posterior to the left atrium?
a) Transverse sinus
b) Oblique sinus
c) Coronary sinus
d) Sinus of Valsalva
Answer: b) Oblique sinus
Explanation: The oblique sinus is a pericardial recess posterior to the left atrium. Its blind-ended nature makes it important for pericardial effusion accumulation. Unlike the transverse sinus, it is not used for surgical clamping.
8. The superior vena cava is located relative to the transverse sinus:
a) Anterior
b) Posterior
c) Lateral
d) Within
Answer: b) Posterior
Explanation: The transverse sinus lies anterior to the superior vena cava, with the sinus running between the arterial trunks and venous inflow. This spatial relationship allows surgical manipulation without damaging major veins.
9. Which sinus is important for placing a retrograde cardioplegia cannula?
a) Transverse sinus
b) Oblique sinus
c) Coronary sinus
d) Superior sinus
Answer: c) Coronary sinus
Explanation: Retrograde cardioplegia cannula is inserted into the coronary sinus to deliver cardioplegia solution. Although near the pericardial sinuses, it is distinct from transverse or oblique sinuses.
10. The transverse sinus separates which two structures?
a) Arterial trunks anteriorly and atria posteriorly
b) Left and right ventricles
c) Pulmonary veins and aorta
d) Coronary arteries and veins
Answer: a) Arterial trunks anteriorly and atria posteriorly
Explanation: The transverse sinus acts as a passage behind the aorta and pulmonary trunk (arterial trunks) and anterior to the left atrium, providing surgical access. This anatomical separation is crucial during open-heart procedures.
Lower Esophageal Sphincter (LES): A specialized segment of smooth muscle at the gastroesophageal junction, preventing reflux of gastric contents.
Tonic Activity: Continuous basal contraction of smooth muscle maintaining closure of a sphincter.
Peristaltic Wave: Coordinated, sequential contraction of esophageal muscles propelling food bolus towards the stomach.
LES Relaxation: Mediated by vagus nerve and nitric oxide; occurs ahead of peristaltic wave during swallowing.
Abdominal Pressure: LES tone increases with elevated intra-abdominal pressure to prevent reflux; reflex relaxation does not occur from pressure increase alone.
Chapter: Gastrointestinal Physiology
Topic: Esophageal Motility
Subtopic: Lower Esophageal Sphincter Function
Lead Question 2012: Which of the following statement regarding lower esophageal sphincter is TRUE?
a) It has no tonic activity
b) It has a tone which is provided by the sympathetic system
c) Relaxes on increasing abdominal pressure
d) Relaxes ahead of the peristaltic wave
Answer: d) Relaxes ahead of the peristaltic wave
Explanation: The lower esophageal sphincter (LES) has continuous tonic activity and prevents gastroesophageal reflux. Its relaxation occurs ahead of the peristaltic wave during swallowing, mediated by the vagus nerve and nitric oxide, allowing the bolus to pass into the stomach. LES tone is not primarily sympathetic and does not relax with increased abdominal pressure alone.
1. What primarily mediates LES relaxation during swallowing?
a) Sympathetic nerves
b) Vagus nerve and nitric oxide
c) Somatic motor fibers
d) Abdominal pressure
Answer: b) Vagus nerve and nitric oxide
Explanation: LES relaxation is coordinated by the vagus nerve and neurotransmitter nitric oxide, ensuring smooth passage of the food bolus. This process is part of the swallowing reflex, and any disruption may lead to dysphagia or gastroesophageal reflux disease.
2. Basal LES tone is maintained by:
a) Continuous tonic activity of smooth muscle
b) Voluntary contraction
c) Sympathetic nervous system exclusively
d) Peristaltic waves
Answer: a) Continuous tonic activity of smooth muscle
Explanation: The LES exhibits basal tonic contraction, which prevents reflux of gastric contents. This tonic activity is intrinsic to smooth muscle and modulated by autonomic input but is not voluntary, emphasizing its role in normal esophageal function.
3. Which condition is associated with failure of LES relaxation?
a) Achalasia
b) GERD
c) Peptic ulcer
d) Hiatal hernia
Answer: a) Achalasia
Explanation: Achalasia is a motility disorder characterized by failure of LES relaxation, leading to esophageal dilation and dysphagia. This occurs due to degeneration of myenteric neurons, highlighting the importance of proper LES neural control.
4. Transient LES relaxations are important for:
a) Swallowing
b) Belching
c) Vomiting
d) Peristalsis
Answer: b) Belching
Explanation: Transient LES relaxations (TLESRs) allow venting of swallowed air from the stomach, producing belching. They are not related to swallowing peristalsis and are physiological but can contribute to reflux if excessive.
5. Increased LES tone is seen in:
a) GERD
b) Achalasia
c) Stress
d) Scleroderma
Answer: b) Achalasia
Explanation: In achalasia, LES shows abnormally increased tone and impaired relaxation, causing difficulty in food passage and esophageal dilation. Recognizing this pathophysiology is key in clinical diagnosis and treatment planning.
6. LES pressure increases during:
a) Swallowing
b) Vomiting
c) Exercise
d) Abdominal straining
Answer: d) Abdominal straining
Explanation: LES pressure increases reflexively during abdominal straining or coughing to prevent gastroesophageal reflux. This adaptive mechanism maintains esophageal integrity and prevents aspiration.
7. Nitric oxide in LES function:
a) Increases basal tone
b) Mediates relaxation ahead of peristaltic wave
c) Inhibits swallowing
d) Stimulates acid secretion
Answer: b) Mediates relaxation ahead of peristaltic wave
Explanation: Nitric oxide is a key neurotransmitter in LES relaxation, acting on smooth muscle to allow bolus passage. Dysfunction can lead to motility disorders, highlighting its clinical importance.
8. Which nerve mediates LES relaxation during swallowing?
a) Phrenic nerve
b) Vagus nerve
c) Hypoglossal nerve
d) Sympathetic thoracic nerves
Answer: b) Vagus nerve
Explanation: Vagus nerve coordinates LES relaxation with peristalsis. Disruption in vagal signaling can impair swallowing and promote esophageal disorders such as reflux or dysmotility.
9. GERD is associated with:
a) Excessive LES relaxation
b) Increased LES tone
c) LES immobility
d) Vagus nerve hyperactivity
Answer: a) Excessive LES relaxation
Explanation: Gastroesophageal reflux disease (GERD) results from frequent transient LES relaxations, allowing gastric acid to reflux into the esophagus, causing heartburn and esophagitis. Understanding LES physiology aids in diagnosis and management.
10. Swallow-induced LES relaxation occurs:
a) Simultaneously with peristaltic wave
b) Ahead of peristaltic wave
c) After peristaltic wave
d) Independent of peristalsis
Answer: b) Ahead of peristaltic wave
Explanation: During swallowing, LES relaxes ahead of the peristaltic wave to allow smooth passage of the bolus into the stomach. This coordinated mechanism is vital for normal esophageal function and prevents obstruction or reflux.
Thoracic Duct: Main lymphatic vessel draining lymph from the majority of the body into the venous system.
Lymphatic System: Network of vessels and nodes that drain interstitial fluid, transport immune cells, and absorb fats from the gut.
Vertebral Levels: Anatomical reference points of vertebrae; T2-T12 are thoracic vertebrae levels.
Lymph Drainage: Thoracic duct drains lymph from left side of body, including left upper limb, thorax, and lower limbs.
Right-to-Left Crossing: Point where thoracic duct crosses midline from right to left before draining into venous circulation at left venous angle.
Chapter: Lymphatic System
Topic: Thoracic Duct Anatomy
Subtopic: Thoracic Duct Course and Vertebral Levels
Lead Question 2012: The thoracic duct crosses from the right to the left at the level of
a) T12 vertebra
b) T6 vertebra
c) T5 vertebra
d) T2 vertebra
Answer: c) T5 vertebra
Explanation: The **thoracic duct** begins at the cisterna chyli and ascends through the thorax on the right side of the vertebral column. It crosses from right to left at approximately the **T5 vertebral level** before draining into the **left venous angle**. This anatomical landmark is important in thoracic surgery and central venous catheter placement to avoid injury to the duct.
1. Where does the thoracic duct drain its lymph?
a) Right subclavian vein
b) Left venous angle
c) Right atrium
d) Thoracic cavity
Answer: b) Left venous angle
Explanation: The **thoracic duct** drains lymph into the **left venous angle**, formed by the junction of the **left internal jugular and subclavian veins**. This drainage allows return of lymph to the systemic circulation, maintaining fluid balance and immune function.
2. The thoracic duct originates from:
a) Thoracic aorta
b) Cisterna chyli
c) Right lymphatic duct
d) Sternal lymph nodes
Answer: b) Cisterna chyli
Explanation: The **cisterna chyli**, located at L1-L2 vertebral level, serves as the origin of the thoracic duct. It collects lymph from the **lower limbs, pelvic cavity, and abdomen**, which then ascends through the thorax to drain into the venous system.
3. The thoracic duct passes through which opening of the diaphragm?
a) Aortic hiatus
b) Caval opening
c) Esophageal hiatus
d) None
Answer: a) Aortic hiatus
Explanation: The **thoracic duct** ascends from the abdomen into the thorax via the **aortic hiatus** of the diaphragm at the T12 level. Understanding its course prevents injury during thoracoabdominal procedures.
4. Clinical significance of thoracic duct injury includes:
a) Pleural effusion
b) Chylothorax
c) Pulmonary embolism
d) Pneumothorax
Answer: b) Chylothorax
Explanation: Injury to the thoracic duct can lead to **chylothorax**, accumulation of lymph in the pleural cavity. It occurs post-thoracic or neck surgery. Knowledge of the crossing at T5 and drainage into the left venous angle is crucial for surgical prevention.
5. On which side of the vertebral column does the thoracic duct ascend initially?
a) Left
b) Right
c) Midline
d) Alternating sides
Answer: b) Right
Explanation: The thoracic duct initially ascends **on the right side** of the vertebral column from the cisterna chyli and crosses to the left at **T5 level**. Awareness of this anatomy is essential during mediastinal and esophageal surgeries to prevent duct injury.
6. The thoracic duct carries lymph from all except:
a) Right upper limb
b) Left lower limb
c) Abdomen
d) Left thorax
Answer: a) Right upper limb
Explanation: The **right upper limb, right thorax, and right head and neck** are drained by the **right lymphatic duct**, while the thoracic duct drains **all left-sided regions and lower body**. This distinction is important for understanding lymphatic drainage patterns.
7. The thoracic duct terminates at:
a) Left brachiocephalic vein
b) Left subclavian vein
c) Left venous angle
d) Right venous angle
Answer: c) Left venous angle
Explanation: The thoracic duct empties into the **left venous angle**, the junction of the **left internal jugular and subclavian veins**. This allows lymph to re-enter the venous circulation efficiently.
8. Which vertebral level corresponds to the cisterna chyli?
a) T12
b) L1-L2
c) T5
d) L3-L4
Answer: b) L1-L2
Explanation: The **cisterna chyli** lies at **L1-L2**, serving as the origin of the thoracic duct. It collects lymph from the abdomen and lower limbs before ascending through the thorax.
9. Which imaging modality best visualizes the thoracic duct?
a) Ultrasound
b) MRI lymphangiography
c) X-ray
d) PET scan
Answer: b) MRI lymphangiography
Explanation: **MRI lymphangiography** provides high-resolution imaging of the thoracic duct, its course, and any obstructions or injuries, which is valuable in planning surgery or treating chylothorax.
10. Surgical injury to thoracic duct at T5 level may cause:
a) Chylopericardium
b) Chylothorax
c) Ascites
d) Pulmonary edema
Answer: b) Chylothorax
Explanation: Injury to the thoracic duct at the **T5 crossing point** can result in **chylothorax**, accumulation of lymph in the pleural cavity. Recognizing its course is essential to avoid this complication during thoracic and esophageal surgery.
Right Coronary Artery (RCA): Supplies blood to the right atrium, right ventricle, SA node, AV node, and part of the ventricular septum.
Ventricular Septum: Wall separating right and left ventricles; blood supply is from both RCA and LAD.
SA Node: Pacemaker of the heart, located in right atrium; receives blood mainly from RCA.
AV Node: Conducting node between atria and ventricles; supplied by RCA in most individuals.
Left Bundle Branch (LBB): Conduction fiber in the left side of interventricular septum; primarily supplied by left anterior descending artery (LAD).
Chapter: Cardiovascular System
Topic: Coronary Circulation
Subtopic: Right Coronary Artery Distribution
Lead Question 2012: Right coronary artery supplies all, except?
a) Anterior 2/3 of ventricular septum
b) SA node
c) AV node
d) LBB
Answer: a) Anterior 2/3 of ventricular septum
Explanation: The **right coronary artery (RCA)** primarily supplies the right atrium, right ventricle, SA node, AV node, and posterior 1/3 of the ventricular septum. The **anterior 2/3 of the septum** and left bundle branch (LBB) are mainly supplied by the **left anterior descending (LAD) artery**, making option (a) the correct choice as it is not supplied by RCA.
1. Which part of the conduction system is mainly supplied by RCA?
a) SA node
b) AV node
c) Bundle of His
d) Purkinje fibers
Answer: a) SA node
Explanation: The **SA node**, located in the right atrium, is the primary pacemaker of the heart. It receives blood from the **RCA in 60% of individuals**, highlighting the artery’s role in maintaining normal sinus rhythm.
2. RCA dominance refers to:
a) RCA supplying LBB
b) RCA giving posterior descending artery
c) RCA supplying LAD territory
d) RCA supplying SA node only
Answer: b) RCA giving posterior descending artery
Explanation: **RCA dominance** occurs when the RCA gives rise to the **posterior descending artery (PDA)**, supplying the posterior interventricular septum. This influences myocardial infarct patterns and clinical outcomes.
3. Posterior 1/3 of ventricular septum is supplied by:
a) RCA
b) LAD
c) Circumflex artery
d) LBB
Answer: a) RCA
Explanation: The **posterior 1/3 of the interventricular septum** is typically supplied by the **RCA** via the posterior descending artery. LAD supplies the anterior 2/3, while the circumflex artery contributes variably. Knowledge of this is critical in managing septal infarctions.
4. Which artery primarily supplies the left bundle branch?
a) RCA
b) LAD
c) Circumflex
d) PDA
Answer: b) LAD
Explanation: The **left bundle branch** is located in the anterior 2/3 of the interventricular septum, which is primarily supplied by the **left anterior descending artery (LAD)**. RCA rarely contributes, highlighting the anatomical separation of conduction system blood supply.
5. RCA supplies AV node in approximately what percentage of individuals?
a) 40%
b) 65%
c) 80%
d) 95%
Answer: b) 65%
Explanation: The **AV node** is supplied by the **RCA in about 65% of individuals**, depending on coronary dominance. Knowledge of this is crucial in planning surgeries or managing conduction abnormalities following RCA occlusion or infarction.
6. Inferior wall myocardial infarction is usually due to occlusion of:
a) LAD
b) RCA
c) Circumflex
d) LBB
Answer: b) RCA
Explanation: **Inferior wall MI** is most commonly caused by occlusion of the **RCA**, which supplies the inferior portion of the right ventricle and posterior interventricular septum. Recognizing artery involvement guides ECG interpretation and intervention.
7. Which coronary artery supplies the posterior descending artery in left-dominant hearts?
a) RCA
b) LAD
c) Circumflex
d) AV node branch
Answer: c) Circumflex
Explanation: In **left-dominant circulation**, the **posterior descending artery (PDA)** arises from the **circumflex artery**, not RCA. This affects myocardial infarct localization and surgical planning, especially in coronary artery bypass grafting.
8. RCA primarily supplies which chamber of the heart?
a) Left atrium
b) Left ventricle
c) Right ventricle
d) Left atrial appendage
Answer: c) Right ventricle
Explanation: The **right coronary artery** predominantly supplies the **right ventricle** and parts of the right atrium. Its occlusion can cause right ventricular infarction, hypotension, and conduction disturbances due to AV node involvement.
9. Which conduction abnormality is commonly seen in RCA infarction?
a) Left bundle branch block
b) AV block
c) Sinus tachycardia
d) Right bundle branch block
Answer: b) AV block
Explanation: RCA infarction may compromise the **AV node**, leading to various degrees of **AV block**. Recognizing this helps in ECG interpretation and deciding temporary pacing in acute inferior myocardial infarction.
10. Anterior 2/3 of interventricular septum is supplied by:
a) RCA
b) LAD
c) Circumflex
d) Right atrial branch
Answer: b) LAD
Explanation: The **left anterior descending artery** supplies the **anterior 2/3 of the interventricular septum**, including the left bundle branch. This is why anterior MI often causes septal and conduction abnormalities, distinguishing it from RCA occlusion.
Waldeyer's Fascia: A connective tissue structure in the pelvic region, providing support to pelvic organs.
Pelvis: The bony cavity containing reproductive and urinary organs, rectum, and associated connective tissue.
Rectum: Terminal part of the large intestine, located posteriorly in the pelvis.
Uterus: Female reproductive organ located in the pelvic cavity, anterior to the rectum.
Bladder: Urinary organ anterior in the pelvis, stores urine; lies in front of uterus in females.
Chapter: Anatomy
Topic: Pelvic Fascia
Subtopic: Waldeyer's Fascia
Lead Question 2012: Waldeyer's fascia lies?
a) In front of the bladder
b) Behind the rectum
c) Between bladder and uterus
d) Between uterus and rectum
Answer: d) Between uterus and rectum
Explanation: Waldeyer's fascia is a fibrous connective tissue layer located **between the uterus and the rectum** in the female pelvis. It provides structural support and separates these organs. Clinically, it is important during pelvic surgeries like hysterectomy or rectal dissection to avoid injury and ensure proper anatomical planes are followed.
1. What is the clinical significance of Waldeyer's fascia?
a) Supports bladder only
b) Important in pelvic surgery for safe dissection
c) Prevents urethral injury
d) Stabilizes ovaries
Answer: b) Important in pelvic surgery for safe dissection
Explanation: Waldeyer's fascia separates the **rectum and uterus**, serving as a landmark during pelvic surgery. Knowledge of this fascia is crucial to avoid damage to pelvic organs, ensure safe dissection, and reduce complications during procedures like hysterectomy or rectal surgery.
2. Waldeyer's fascia is classified as:
a) Visceral fascia
b) Parietal fascia
c) Retropubic fascia
d) Deep perineal fascia
Answer: a) Visceral fascia
Explanation: Waldeyer's fascia is part of the **visceral pelvic fascia**, covering and supporting pelvic organs like uterus and rectum. Visceral fascia is distinguished from parietal fascia, which lines the pelvic walls. Its role is structural support and providing surgical landmarks.
3. Which structure lies posterior to Waldeyer's fascia?
a) Uterus
b) Bladder
c) Rectum
d) Ovary
Answer: c) Rectum
Explanation: The **rectum** is located posterior to Waldeyer's fascia. This fascia forms a plane between the rectum and uterus. Proper identification is critical during rectal or gynecologic surgery to prevent injury and ensure adequate separation of organs.
4. During hysterectomy, why is Waldeyer's fascia important?
a) Prevents bladder injury
b) Guides safe dissection plane
c) Strengthens ligaments
d) Reduces postoperative bleeding
Answer: b) Guides safe dissection plane
Explanation: Surgeons use Waldeyer's fascia as a **dissection landmark** to safely separate the rectum from the uterus during hysterectomy. Identifying this plane reduces the risk of rectal injury and ensures precise removal of uterine structures while preserving surrounding organs.
5. Which fascia lies anterior to the uterus?
a) Waldeyer's fascia
b) Vesicouterine fascia
c) Rectovaginal fascia
d) Endopelvic fascia
Answer: b) Vesicouterine fascia
Explanation: The **vesicouterine fascia** lies between the bladder and uterus. In contrast, Waldeyer's fascia lies posterior to the uterus. Recognizing anterior and posterior fascial planes is critical during pelvic surgery to prevent bladder or rectal injuries.
6. Waldeyer's fascia is most closely associated with which surgical procedure?
a) Appendectomy
b) Low anterior resection
c) Hysterectomy
d) Cholecystectomy
Answer: c) Hysterectomy
Explanation: Waldeyer's fascia is critical in **hysterectomy** to identify the plane between uterus and rectum. Proper dissection along this fascia prevents rectal injury and ensures complete removal of uterine tissue. It is also relevant in rectal surgery to maintain surgical planes.
7. Which structure is separated from the uterus by Waldeyer's fascia?
a) Bladder
b) Rectum
c) Ovaries
d) Fallopian tubes
Answer: b) Rectum
Explanation: Waldeyer's fascia separates the **uterus from the rectum**, providing a safe surgical plane. This separation reduces the risk of rectal injury during posterior pelvic surgeries, including hysterectomy and rectal mobilization.
8. Injury to Waldeyer's fascia during surgery may lead to:
a) Bladder perforation
b) Rectal injury
c) Ureteral obstruction
d) Vaginal fistula
Answer: b) Rectal injury
Explanation: Since Waldeyer's fascia lies between the **uterus and rectum**, inadvertent injury during surgery can cause **rectal perforation** or bleeding. Recognizing its location helps surgeons preserve rectal integrity and reduce postoperative complications.
9. Waldeyer's fascia is a part of which broader pelvic structure?
a) Endopelvic fascia
b) Parietal fascia
c) Perineal body
d) Obturator fascia
Answer: a) Endopelvic fascia
Explanation: Waldeyer's fascia is a component of the **endopelvic fascia**, which supports pelvic organs and provides surgical planes. It helps separate rectum and uterus, maintaining pelvic organ integrity during gynecologic and colorectal surgeries.
10. Which imaging modality can visualize Waldeyer's fascia in surgical planning?
a) Ultrasound
b) MRI
c) X-ray
d) CT scan
Answer: b) MRI
Explanation: **MRI** provides excellent soft tissue resolution, allowing visualization of Waldeyer's fascia between the uterus and rectum. This imaging is useful in preoperative planning for pelvic surgery, helping to avoid rectal injury and correctly identify fascial planes.
IVC Filter: A medical device inserted into the inferior vena cava to prevent pulmonary embolism by trapping large thrombi.
Pulmonary Embolism (PE): Obstruction of pulmonary arteries by blood clots, which can be life-threatening.
Thrombosis: Formation of a blood clot inside a blood vessel, obstructing blood flow.
Native Vessel Disease: Pre-existing disease in the patient’s own veins or arteries, e.g., deep vein thrombosis (DVT).
Symptom Relief: Reduction of pain, swelling, or discomfort associated with vascular obstruction.
Chapter: Cardiovascular System
Topic: Venous Thrombosis Management
Subtopic: IVC Filter
Lead Question 2012: IVC filter is used in following except:
a) To reduces symptoms
b) Negligible size of emboli
c) To prolong life
d) To prevent progress of native blood vessel disease
Answer: b) Negligible size of emboli
Explanation: IVC filters are designed to trap large thrombi from the lower extremities, preventing pulmonary embolism. They do not trap **small or negligible-sized emboli**, which pass through easily. Indications include preventing PE in patients with contraindications to anticoagulation, symptom relief, and occasionally improving survival in high-risk cases, but they do not directly halt progression of underlying vein disease.
1. What is the primary clinical indication for IVC filter placement?
a) Primary prevention in low-risk patients
b) Pulmonary embolism prevention when anticoagulation is contraindicated
c) Routine prophylaxis after surgery
d) Treating leg edema
Answer: b) Pulmonary embolism prevention when anticoagulation is contraindicated
Explanation: IVC filters are primarily indicated for patients at high risk of pulmonary embolism who cannot receive anticoagulants due to bleeding or other contraindications. They physically trap large thrombi traveling from deep veins. They are not used routinely in low-risk patients or solely for edema relief.
2. Which type of thrombi do IVC filters primarily capture?
a) Small microemboli
b) Large thrombi from deep veins
c) Platelet aggregates only
d) Fat emboli
Answer: b) Large thrombi from deep veins
Explanation: IVC filters are designed to trap **large thrombi** traveling from the lower extremities to prevent pulmonary embolism. Microemboli often pass through the filter, and fat emboli or platelet aggregates are not targeted. Correct placement and sizing are critical to maximize effectiveness.
3. Which is a potential complication of IVC filter placement?
a) Migration of the filter
b) Infection
c) Caval perforation
d) All of the above
Answer: d) All of the above
Explanation: Complications of IVC filters include **migration**, infection, caval perforation, thrombosis at the filter site, and filter fracture. Clinicians must weigh the benefits against potential risks and remove temporary filters when no longer indicated.
4. Which patients are considered for temporary or retrievable IVC filters?
a) Patients with permanent contraindication to anticoagulants
b) Patients undergoing high-risk surgery with transient PE risk
c) Patients with chronic DVT
d) All patients regardless of risk
Answer: b) Patients undergoing high-risk surgery with transient PE risk
Explanation: Temporary or retrievable IVC filters are placed for patients with **transient high risk** of pulmonary embolism, such as perioperative periods, and removed once risk subsides. Permanent filters are used for chronic contraindication to anticoagulation.
5. Does IVC filter placement directly prolong survival in all patients?
a) Yes, universally
b) No, mainly in high-risk PE
c) Only in low-risk patients
d) Only with concurrent anticoagulation
Answer: b) No, mainly in high-risk PE
Explanation: IVC filters may prolong survival in select **high-risk pulmonary embolism patients**, particularly those who cannot be anticoagulated. Routine use in all patients does not confer mortality benefit, as small emboli can still pass, and long-term complications may offset benefit.
6. Which imaging modality is used to guide IVC filter placement?
a) Ultrasound
b) Fluoroscopy
c) MRI
d) Chest X-ray
Answer: b) Fluoroscopy
Explanation: Fluoroscopy provides real-time imaging to accurately position the IVC filter at the correct level, typically below the renal veins. Ultrasound may assist in venous access, but MRI and chest X-ray are not used for procedural guidance.
7. Which factor reduces effectiveness of IVC filters?
a) Large thrombi
b) Multiple emboli
c) Small or negligible emboli
d) Correct positioning
Answer: c) Small or negligible emboli
Explanation: IVC filters cannot capture **small thrombi or microemboli**, which pass through the device, potentially causing pulmonary embolism. Correct positioning enhances efficacy for large emboli, but small emboli remain a limitation.
8. Which anticoagulation status typically warrants IVC filter placement?
a) Fully anticoagulated
b) Contraindication to anticoagulation
c) Minor risk of PE
d) None of the above
Answer: b) Contraindication to anticoagulation
Explanation: IVC filters are indicated when **anticoagulation is contraindicated** due to bleeding or other risks. Patients already safely anticoagulated typically do not require filters, as medications effectively prevent PE. Filters are adjunctive therapy, not first-line for all patients.
9. What is a major long-term risk of permanent IVC filters?
a) Filter migration
b) Caval thrombosis
c) Fracture of filter struts
d) All of the above
Answer: d) All of the above
Explanation: Long-term complications of permanent IVC filters include **migration**, **caval thrombosis**, and **filter fracture**. These risks highlight the importance of using filters only when indicated and considering retrievable filters for temporary high-risk scenarios.
10. Which statement is correct regarding IVC filters and native vessel disease?
a) IVC filter prevents progression of native DVT
b) Filter only traps emboli but does not cure underlying vein disease
c) Filter dissolves thrombi
d) Filter replaces anticoagulation permanently
Answer: b) Filter only traps emboli but does not cure underlying vein disease
Explanation: IVC filters **trap large emboli** to prevent PE but do not prevent or treat the underlying thrombosis or progression of native vessel disease. Anticoagulation or other therapies are needed to manage the primary DVT. Filters are an adjunct, not a definitive cure.
Triangle of Auscultation: A small triangular area on the back where the thoracic wall is thin, allowing clear lung auscultation.
Trapezius: Large superficial muscle of the back responsible for moving the scapula and supporting arm movements.
Latissimus Dorsi: Broad, flat muscle covering lower back; involved in arm adduction, extension, and internal rotation.
Rhomboid Major: Muscle connecting spine to scapula, retracting and stabilizing the scapula.
Scapula: Shoulder blade bone, forms part of the shoulder girdle; not a muscular boundary.
Chapter: Anatomy
Topic: Back Muscles
Subtopic: Triangle of Auscultation
Lead Question 2012: All form boundaries of triangle of auscultation except:
a) Trapezius
b) Latissmusdorsi
c) Scapula
d) Rhomboid major
Answer: c) Scapula
Explanation: The triangle of auscultation is bordered by the **trapezius** medially, **rhomboid major** laterally, and **latissimus dorsi** inferiorly. The scapula is a bone overlying the area, not a muscular boundary. Clinically, this triangle is important because placing a stethoscope here allows better auscultation of lung sounds due to reduced muscular thickness.
1. Which muscle forms the medial border of the triangle of auscultation?
a) Rhomboid major
b) Trapezius
c) Latissimus dorsi
d) Serratus anterior
Answer: b) Trapezius
Explanation: The medial border of the triangle of auscultation is formed by the **trapezius**. This muscle extends from the occipital bone to the lower thoracic vertebrae, covering part of the back. Its lateral border is formed by rhomboid major, and inferiorly by latissimus dorsi.
2. The inferior boundary of the triangle of auscultation is formed by:
a) Latissimus dorsi
b) Trapezius
c) Rhomboid minor
d) Erector spinae
Answer: a) Latissimus dorsi
Explanation: The **latissimus dorsi** forms the inferior boundary of the triangle. It is a broad, flat muscle involved in arm adduction, extension, and medial rotation. Its position makes the area thin and suitable for auscultating lung sounds clinically.
3. Lateral border of the triangle of auscultation is formed by:
a) Trapezius
b) Rhomboid major
c) Serratus posterior superior
d) Levator scapulae
Answer: b) Rhomboid major
Explanation: The **rhomboid major** forms the lateral border of the triangle of auscultation. It retracts and stabilizes the scapula, and its thin overlay in this area allows better lung auscultation. Trapezius is medial, latissimus dorsi is inferior.
4. Clinically, why is the triangle of auscultation important?
a) Muscle injection site
b) Better lung auscultation
c) Site for nerve block
d) Bone palpation
Answer: b) Better lung auscultation
Explanation: The triangle of auscultation is a clinically significant area because muscular thickness is minimal, allowing stethoscopes to detect lung sounds clearly. Physicians often ask patients to fold arms over chest to enlarge the triangle for auscultation.
5. Which posture enlarges the triangle of auscultation for examination?
a) Arms at sides
b) Hands behind head
c) Hands folded across chest
d) Forward bending
Answer: c) Hands folded across chest
Explanation: Folding the arms across the chest rotates the scapula laterally, widening the triangle of auscultation. This allows easier placement of the stethoscope for clear lung sound assessment. Forward bending or arms behind head do not effectively enlarge the area.
6. Which nerve is closely related to the triangle of auscultation?
a) Long thoracic nerve
b) Thoracodorsal nerve
c) Spinal accessory nerve
d) Axillary nerve
Answer: a) Long thoracic nerve
Explanation: The **long thoracic nerve** runs along the lateral chest wall near the triangle, innervating serratus anterior. Injury can cause winged scapula. Awareness of nearby nerves is important during clinical procedures in the area.
7. Which imaging modality can show muscles forming the triangle of auscultation?
a) X-ray
b) MRI
c) Ultrasound
d) CT scan
Answer: b) MRI
Explanation: MRI can clearly visualize soft tissues including trapezius, rhomboid major, and latissimus dorsi, demonstrating the triangle of auscultation. Ultrasound can also be used, but X-ray shows only bones. CT scan is less commonly used for muscle visualization.
8. Which condition can make auscultation through this triangle more difficult?
a) Muscle hypertrophy
b) Muscle atrophy
c) Thin body habitus
d) Forward flexion
Answer: a) Muscle hypertrophy
Explanation: Hypertrophy of trapezius, rhomboid, or latissimus dorsi increases muscle thickness, making lung auscultation more difficult. Thin body habitus enhances auscultation. Clinical positioning can compensate partially, but hypertrophy reduces the acoustic window.
9. Which muscle is superficial and must be displaced to access the triangle?
a) Trapezius
b) Rhomboid minor
c) Levator scapulae
d) Serratus anterior
Answer: a) Trapezius
Explanation: The trapezius is superficial and overlies part of the triangle. During clinical examination, scapular rotation moves the trapezius laterally, allowing access to the triangle of auscultation. Deep muscles like rhomboid minor remain under trapezius.
10. Which movement of the scapula enlarges the triangle laterally?
a) Elevation
b) Retraction
c) Protraction
d) Depression
Answer: c) Protraction
Explanation: Lateral protraction of the scapula moves it away from the vertebral column, widening the triangle of auscultation. This facilitates auscultation. Retraction or elevation reduces the area, making examination more difficult.
Mitral Valve Prolapse (MVP): A condition in which the mitral valve leaflets bulge into the left atrium during systole.
Stroke: Acute neurological deficit due to impaired blood flow to the brain.
Infective Endocarditis: Infection of the endocardial surface of the heart, often involving valves.
Mitral Stenosis: Narrowing of the mitral valve opening causing obstructed blood flow from left atrium to ventricle.
Ventricular Arrhythmia: Abnormal rhythm originating from the ventricles, can be life-threatening.
Chapter: Cardiovascular System
Topic: Valvular Heart Disease
Subtopic: Mitral Valve Disorders
Lead Question 2012: Which of the following complications is not seen in mitral valve prolapse?
a) Stroke
b) Infective endocarditis
c) Mitral stenosis
d) Ventricular arrhythmia
Answer: c) Mitral stenosis
Explanation: Mitral valve prolapse (MVP) usually leads to complications such as mitral regurgitation, arrhythmias including ventricular arrhythmias, infective endocarditis, and rarely stroke due to embolic phenomena. However, mitral stenosis, which is narrowing of the mitral valve, is not a complication of MVP. The valve in MVP is typically redundant and floppy, not stenotic. Clinical presentations often include mid-systolic click, palpitations, and occasional thromboembolic events.
1. Which auscultatory finding is most characteristic of mitral valve prolapse?
a) Opening snap
b) Mid-systolic click
c) S3 gallop
d) Continuous murmur
Answer: b) Mid-systolic click
Explanation: The mid-systolic click is characteristic of MVP due to sudden tensing of the redundant mitral leaflet. It is often followed by a late systolic murmur if regurgitation is present. The opening snap is associated with mitral stenosis, S3 with volume overload, and continuous murmur with patent ductus arteriosus.
2. Which arrhythmia is most commonly associated with mitral valve prolapse?
a) Atrial fibrillation
b) Ventricular tachycardia
c) Sinus bradycardia
d) Junctional rhythm
Answer: b) Ventricular tachycardia
Explanation: Ventricular arrhythmias, including ventricular tachycardia, are commonly seen in MVP patients and can rarely lead to sudden cardiac death. Atrial fibrillation is more common in significant mitral regurgitation from other causes. Sinus bradycardia and junctional rhythms are not typical complications of MVP.
3. What is the typical murmur associated with MVP?
a) Holosystolic murmur at apex
b) Late systolic murmur with mid-systolic click
c) Diastolic murmur at apex
d) Continuous murmur at upper sternal border
Answer: b) Late systolic murmur with mid-systolic click
Explanation: The hallmark of MVP is a mid-systolic click due to sudden prolapse of the valve, often followed by a late systolic murmur if regurgitation is present. Holosystolic murmur occurs in primary mitral regurgitation, diastolic murmur in stenosis, and continuous murmur in PDA.
4. Which of the following is the most common symptom of MVP?
a) Dyspnea
b) Palpitations
c) Chest pain
d) Syncope
Answer: b) Palpitations
Explanation: Palpitations are the most common symptom due to arrhythmias in MVP. Chest pain and dyspnea may occur, but syncope is less common. These symptoms are often associated with autonomic dysfunction and ventricular ectopy.
5. Which imaging modality is most definitive for diagnosing MVP?
a) Chest X-ray
b) Echocardiography
c) ECG
d) Cardiac MRI
Answer: b) Echocardiography
Explanation: Echocardiography is the gold standard for diagnosing MVP. It shows leaflet prolapse >2 mm above the mitral annulus in systole. Chest X-ray is nonspecific, ECG detects arrhythmias but not structural changes, and cardiac MRI is rarely required for diagnosis.
6. Which of the following increases the risk of sudden cardiac death in MVP patients?
a) Mild mitral regurgitation
b) Complex ventricular arrhythmias
c) Isolated mid-systolic click
d) Normal ECG
Answer: b) Complex ventricular arrhythmias
Explanation: Complex ventricular arrhythmias in MVP, especially in patients with severe regurgitation or fibrosis, can lead to sudden cardiac death. Mild regurgitation and isolated clicks are low-risk findings. Normal ECG does not rule out MVP but indicates lower arrhythmic risk.
7. Which of the following prophylactic measures is indicated for MVP with prior endocarditis?
a) Beta-blockers
b) Antibiotic prophylaxis before dental procedures
c) ACE inhibitors
d) Anticoagulants
Answer: b) Antibiotic prophylaxis before dental procedures
Explanation: Patients with MVP who have a history of infective endocarditis require antibiotic prophylaxis before invasive dental or surgical procedures. Beta-blockers are used for symptomatic palpitations, ACE inhibitors for heart failure, and anticoagulants only in atrial fibrillation or embolic risk.
8. Which lab test can support the diagnosis of embolic complications in MVP?
a) ESR
b) Blood cultures
c) Brain imaging (CT/MRI)
d) Troponin I
Answer: c) Brain imaging (CT/MRI)
Explanation: Brain imaging is indicated if embolic stroke is suspected in MVP. Blood cultures detect endocarditis. ESR is nonspecific, and troponin I is used in myocardial injury, not embolic events from MVP.
9. Which lifestyle measure is recommended in symptomatic MVP patients?
a) Avoid caffeine and stimulants
b) High-salt diet
c) Sedentary lifestyle
d) Smoking
Answer: a) Avoid caffeine and stimulants
Explanation: MVP symptoms like palpitations can worsen with caffeine, stimulants, and stress. Lifestyle modification, including regular mild exercise and stress management, helps. High-salt diets, sedentary lifestyle, and smoking can worsen cardiac risk and are not advised.
10. Which pharmacological therapy is preferred for symptomatic MVP with palpitations?
a) Beta-blockers
b) Calcium channel blockers
c) Diuretics
d) Nitrates
Answer: a) Beta-blockers
Explanation: Beta-blockers are first-line therapy for symptomatic MVP patients experiencing palpitations or anxiety-related symptoms. They reduce heart rate, decrease arrhythmic burden, and improve quality of life. Calcium channel blockers are secondary options, while diuretics and nitrates are not indicated for arrhythmias in MVP.