Cardiology Practice Questions

Q: A 42-year-old man presents with dizziness on standing. His systolic blood pressure falls by 50 mm Hg and his heart rate is 52/min. What is the likely cause?

Pheochromocytoma. **Explanation:** The clinical presentation describes **orthostatic hypotension** (a drop in systolic BP ≥20 mmHg) accompanied by **inappropriate bradycardia** (lack of compensatory tachycardia) [1]. In **Pheochromocytoma**, while the classic triad is headache, sweating, and palpitations, chronic excess of catecholamines leads to severe **volume depletion** due to pressure natriuresis and chronic vasoconstriction. When the patient stands, the depleted intravascular volume causes a significant drop in blood pressure [2]. The presence of bradycardia (or a lack of tachycardia) in this context is a high-yield NEET-PG finding, often attributed to **baroreceptor resetting** or catecholamine-induced cardiomyopathy/autonomic dysfunction [3]. **Analysis of Incorrect Options:** * **Congestive Heart Failure (CHF):** While CHF can cause hypotension, it typically presents with compensatory tachycardia and signs of fluid overload (edema, JVP elevation), not bradycardia. * **Inferior Wall MI:** While this can cause bradycardia (due to Bezold-Jarisch reflex or SA/AV node ischemia), it presents with acute chest pain and ECG changes, and orthostatic hypotension is not the primary presenting feature. * **Theophylline Toxicity:** This typically causes **tachycardia**, arrhythmias, and seizures due to its phosphodiesterase inhibition and adenosine antagonism. **NEET-PG Clinical Pearls:** * **Rule of 10s for Pheo:** 10% bilateral, 10% malignant, 10% extra-adrenal (Paraganglioma), 10% pediatric, 10% familial. * **Orthostatic Hypotension in Pheo:** Paradoxically, a patient with hypertension who also shows orthostatic hypotension is a classic clue for Pheochromocytoma. * **Pre-op Management:** Always give **Alpha-blockers first** (e.g., Phenoxybenzamine) followed by Beta-blockers to avoid an uninhibited alpha-mediated hypertensive crisis.

Q: Giant a waves in JVP are seen in which of the following conditions?

Complete heart block. **Explanation:** The **'a' wave** in the Jugular Venous Pulse (JVP) represents **atrial contraction**. Under normal circumstances, the right atrium contracts when the tricuspid valve is open, pushing blood into the right ventricle. **Giant 'a' waves** (also known as Cannon 'a' waves) occur when the right atrium contracts against a **closed tricuspid valve**. In **Complete Heart Block (3rd-degree AV block)**, there is total AV dissociation [3]. The atria and ventricles beat independently [2]. Occasionally, the P-wave (atrial contraction) coincides with the QRS complex (ventricular contraction/systole). When this happens, the atrium contracts against a closed tricuspid valve, causing a massive backflow of pressure into the jugular vein, visible as a "cannon" wave. **Analysis of Incorrect Options:** * **Tachycardia:** Generally shortens the filling time but does not inherently cause AV dissociation or contraction against a closed valve. * **Atrial Ectopic:** While it may cause a slightly prominent 'a' wave if it occurs early, it does not typically produce the classic "giant" or "cannon" waves seen in dissociation. * **1st Degree Heart Block:** Here, every atrial impulse is conducted to the ventricle, just with a delay (prolonged PR interval) [1]. Since the tricuspid valve is open during atrial contraction, it results in a **soft/small 'a' wave**, not a giant one. **High-Yield Clinical Pearls for NEET-PG:** * **Regular Cannon 'a' waves:** Seen in Junctional Rhythm or SVT (Atrial and ventricular contraction are synchronized). * **Irregular Cannon 'a' waves:** Pathognomonic for **Complete Heart Block** or Ventricular Tachycardia (due to AV dissociation) [3]. * **Absent 'a' waves:** Seen in **Atrial Fibrillation** (no coordinated atrial contraction). * **Prominent/Large 'a' waves (not cannon):** Seen in Right Ventricular Hypertrophy, Tricuspid Stenosis, and Pulmonary Hypertension (atrium pushing against a stiff/obstructed valve).

Q: Comment on the ECG finding shown below?

Epsilon wave. ***Epsilon wave*** - A **small deflection** after the QRS complex that represents **delayed activation** of parts of the right ventricle, pathognomonic for **arrhythmogenic right ventricular cardiomyopathy (ARVC)**. - ARVC involves **fibro-fatty replacement** of right ventricular myocardium, commonly affects **young athletes**, and carries high risk of **sudden cardiac death**. *Delta wave* - Represents **pre-excitation** via an **accessory pathway** in **Wolff-Parkinson-White syndrome**, appearing as a **slurred upstroke** of the QRS complex. - Associated with **short PR interval** and **wide QRS complex**, not the small post-QRS deflection seen in epsilon waves. *Prominent U wave* - A **positive deflection** after the T wave, commonly seen in **hypokalemia**, **bradycardia**, or **quinidine toxicity**. - Appears as a **separate wave** following the T wave, distinct from the small post-QRS epsilon wave pattern. *Deep Q wave* - Represents **myocardial necrosis** in **myocardial infarction**, appearing as **deep negative deflections** at the beginning of the QRS complex. - Indicates **full-thickness myocardial damage** and is unrelated to the conduction abnormalities seen in ARVC.

Q: A 55-year-old female presents with Levine sign, hiccups, and vomiting episodes. On examination, HR=50/min with BP =100/60 mm Hg with elevated JVP. ECG technician is yet to arrive. Which coronary artery is likely to be involved?

RCA. ### Explanation The clinical presentation points toward an **Inferior Wall Myocardial Infarction (IWMI)** with Right Ventricular (RV) involvement. **1. Why RCA is the correct answer:** * **Levine Sign:** Indicates ischemic chest pain. * **Hiccups and Vomiting:** These are classic "autonomic symptoms" often associated with inferior wall MI due to irritation of the **vagus nerve** (Bezold-Jarisch reflex) and diaphragmatic irritation [2]. * **Bradycardia (HR=50/min):** The **Right Coronary Artery (RCA)** supplies the SA node (in 60% of people) and the AV node (in 90%). Ischemia to the RCA frequently leads to sinus bradycardia or AV blocks [2]. * **Elevated JVP + Hypotension:** This triad (with clear lungs) suggests **Right Ventricular Infarction**, which occurs in nearly 40% of RCA-related inferior MIs [2]. **2. Why other options are incorrect:** * **LAD (Left Anterior Descending):** Usually causes Anterior Wall MI. This typically presents with tachycardia (due to sympathetic activation) and signs of left heart failure (pulmonary edema), not bradycardia or elevated JVP. * **LCX (Left Circumflex):** Supplies the lateral wall. While it can occasionally supply the inferior wall (in left-dominant circulation), the combination of bradycardia and RV involvement is much more characteristic of the RCA [1]. * **Left Main:** Occlusion usually leads to massive anterolateral infarction, cardiogenic shock, and high mortality; it does not typically present with isolated inferior/RV symptoms. **Clinical Pearls for NEET-PG:** * **Bezold-Jarisch Reflex:** Triad of bradycardia, hypotension, and apnea triggered by inferior wall ischemia [3]. * **RV Infarction Management:** Avoid nitrates, diuretics, and morphine (they decrease preload). The treatment of choice is **IV fluids** to maintain right-sided filling pressures. * **ECG Clue:** ST-elevation in Lead III > Lead II strongly suggests RCA over LCX.

Q: Which of the following is the most common cause of midsystolic murmur in adults?

Aortic stenosis. ### Explanation **1. Why Aortic Stenosis (AS) is Correct:** A midsystolic (ejection systolic) murmur occurs when blood is forced through a narrowed or obstructed outflow tract during the peak of ventricular contraction. **Aortic Stenosis** is the most common cause of this murmur in adults, typically resulting from age-related degenerative calcification (in older adults) or a congenital bicuspid valve (in younger adults) [1]. As the left ventricle contracts, the pressure gradient across the stenotic valve increases, reaching a peak in mid-systole, which creates the characteristic "crescendo-decrescendo" sound [1],[2]. **2. Why the Other Options are Incorrect:** * **B. Aortic Regurgitation:** This produces a **decrescendo early diastolic murmur**, heard best at the left sternal border, as blood flows backward from the aorta into the left ventricle during diastole [3]. * **C. Hypertrophic Obstructive Cardiomyopathy (HOCM):** While HOCM does cause a midsystolic murmur (due to dynamic left ventricular outflow tract obstruction), it is significantly **less common** in the general adult population compared to degenerative aortic stenosis. * **D. All of the above:** Incorrect because the mechanisms and timing of the murmurs for AR and AS are fundamentally different. **3. NEET-PG High-Yield Clinical Pearls:** * **AS Murmur Characteristics:** Best heard at the right second intercostal space; radiates to the **carotids** [1]. * **Dynamic Auscultation:** The murmur of AS **decreases** with Valsalva (less preload = less flow), whereas the murmur of HOCM **increases** with Valsalva. * **Classic Triad of AS (SAD):** **S**yncope, **A**ngina, and **D**yspnea. * **Physical Sign:** Look for *Pulsus Parvus et Tardus* (slow-rising, low-amplitude pulse) in severe AS [1].

Q: Which condition is most likely associated with the given ECG tracing?

Renal failure. ***Renal failure*** - **Hyperkalemia** from impaired potassium excretion leads to characteristic ECG changes including **peaked T waves**, **widened QRS complexes**, and potential **sine wave** pattern. - Progressive ECG changes occur as potassium levels rise: **peaked T waves** → **PR prolongation** → **QRS widening** → **sine wave** → **asystole**. *Conn's syndrome* - Causes **hypokalemia** due to excess mineralocorticoid activity, leading to **flattened T waves** and **U waves**, not peaked T waves. - Associated with **hypertension** and **metabolic alkalosis**, but ECG changes are opposite to those seen in hyperkalemia. *Multiple myeloma* - Primarily causes **hypercalcemia** which produces **shortened QT intervals** on ECG, not the peaked T waves of hyperkalemia. - May also cause **renal dysfunction** as a secondary effect, but the primary electrolyte abnormality is elevated calcium. *SIADH* - Results in **hyponatremia** which typically does not produce specific characteristic ECG changes like peaked T waves. - May cause **nonspecific ST-T wave changes** in severe cases, but hyperkalemic ECG patterns are not associated with low sodium levels.

Q: What is the most common valvular lesion seen with carcinoid syndrome?

Tricuspid insufficiency and pulmonic stenosis. ### Explanation **Underlying Medical Concept** Carcinoid heart disease occurs in approximately 50% of patients with systemic carcinoid syndrome (usually from metastatic neuroendocrine tumors). The pathology is driven by high circulating levels of **serotonin (5-HT)**, which causes plaque-like fibrous endocardial thickening. These plaques predominantly affect the **right side of the heart**. The serotonin causes the tricuspid valve leaflets to become thickened, shortened, and retracted, leading to **Tricuspid Insufficiency (Regurgitation)** [1]. Simultaneously, the pulmonic valve cusps become scarred and immobile, leading to **Pulmonic Stenosis**. **Analysis of Options** * **Option B (Correct):** Serotonin-induced fibrosis typically results in a "fixed" open tricuspid valve (Insufficiency) and a narrowed pulmonic orifice (Stenosis). [1] * **Option A:** While pulmonic stenosis is correct, the tricuspid valve is more commonly incompetent (regurgitant) than stenotic. * **Options C & D:** Left-sided lesions (Mitral/Aortic) are **rare** because the lungs contain **monoamine oxidase (MAO)**, which inactivates serotonin before it reaches the left heart. Left-sided involvement only occurs in the presence of a right-to-left shunt (e.g., PFO) or primary bronchial carcinoids. **NEET-PG High-Yield Pearls** * **Biochemical Marker:** 24-hour urinary **5-HIAA** (metabolite of serotonin) is used for diagnosis. * **Location:** Right-sided lesions are the hallmark. [1] * **Pathognomonic Feature:** Glistening white "carcinoid plaques" on the endocardial surface. * **Management:** Somatostatin analogues (Octreotide) help control symptoms, but definitive treatment for severe valve disease is surgical replacement.

Q: Wolff-Parkinson-White (WPW) syndrome is characterized by which of the following electrocardiographic findings?

Delta wave. **Explanation:** **Wolff-Parkinson-White (WPW) Syndrome** is a pre-excitation syndrome caused by the presence of an accessory pathway (the **Bundle of Kent**) that bypasses the AV node [1]. This allows electrical impulses to reach the ventricles earlier than usual. 1. **Why "Delta wave" is correct:** In WPW, the impulse travels through the accessory pathway faster than the slow-conducting AV node. This results in premature ventricular depolarization, which manifests on an ECG as a slurred upstroke of the QRS complex, known as a **Delta wave** [1]. Because of this pre-excitation, the **PR interval is shortened (<0.12s)** and the **QRS complex is widened** [1], [2]. 2. **Why other options are incorrect:** * **Prolonged PR interval:** This is characteristic of First-degree AV block. In WPW, the PR interval is characteristically *shortened* because the AV nodal delay is bypassed [1]. * **U wave:** This is a small wave following the T wave, most commonly associated with **hypokalemia**, hypercalcemia, or thyrotoxicosis. * **Heart block:** This refers to a delay or interruption in conduction (e.g., AV block), whereas WPW is a state of "accelerated" conduction. **High-Yield Clinical Pearls for NEET-PG:** * **Classic Triad:** Short PR interval ( 120ms) [1]. * **Associated Arrhythmia:** Most commonly associated with AV Reentrant Tachycardia (AVRT) [2]. * **Drug Contraindication:** Avoid **ABCD** drugs (Adenosine, Beta-blockers, Calcium channel blockers, Digoxin) in WPW with Atrial Fibrillation, as they block the AV node and may favor conduction through the accessory pathway, leading to Ventricular Fibrillation [2]. * **Definitive Treatment:** Radiofrequency ablation of the accessory pathway.

Question 1

A 42-year-old man presents with dizziness on standing. His systolic blood pressure falls by 50 mm Hg and his heart rate is 52/min. What is the likely cause?

Accepted Answer

Pheochromocytoma

Answer

Congestive heart failure

Answer

Inferior wall myocardial infarction

Answer

Theophylline toxicity

Question 2

Giant a waves in JVP are seen in which of the following conditions?

Accepted Answer

Complete heart block

Answer

Tachycardia

Answer

Atrial ectopic

Answer

1st degree heart block

Question 3

Comment on the ECG finding shown below?

Accepted Answer

Epsilon wave

Answer

Delta wave

Answer

Prominent U wave

Answer

Deep Q wave

Question 4

A 55-year-old female presents with Levine sign, hiccups, and vomiting episodes. On examination, HR=50/min with BP =100/60 mm Hg with elevated JVP. ECG technician is yet to arrive. Which coronary artery is likely to be involved?

Accepted Answer

RCA

Answer

LAD

Answer

LCX

Answer

Left main coronary artery

Question 5

Which of the following is the most common cause of midsystolic murmur in adults?

Accepted Answer

Aortic stenosis

Answer

Aortic regurgitation

Answer

Hypertrophic obstructive cardiac myopathy

Answer

All of the above

Question 6

Which condition is most likely associated with the given ECG tracing?

Accepted Answer

Renal failure

Answer

Conn's syndrome

Answer

Multiple myeloma

Answer

SIADH

Question 7

All of the following predispose to Ischemic Heart Disease except?

Accepted Answer

Alcoholism

Answer

Smoking

Answer

Sedentary habits

Answer

Diabetes

Question 8

What is the most common valvular lesion seen with carcinoid syndrome?

Accepted Answer

Tricuspid insufficiency and pulmonic stenosis

Answer

Tricuspid stenosis and pulmonic stenosis

Answer

Mitral stenosis and aortic stenosis

Answer

Mitral insufficiency and aortic stenosis

Question 9

Wolff-Parkinson-White (WPW) syndrome is characterized by which of the following electrocardiographic findings?

Accepted Answer

Delta wave

Answer

Prolonged PR interval

Answer

U wave

Answer

Heart block

Question 10

Which one of the following is of most serious prognostic significance in a patient of essential hypertension?

Accepted Answer

Papilledema and progressive renal failure

Answer

Diastolic blood pressure greater than 130 mmHg

Answer

Transient ischemic attacks

Answer

Left ventricular hypertrophy

Cardiology — MCQs

Cardiology — MCQs

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