Cardiology Practice Questions

Q: What is the best drug for the rhythm disorder shown below?

Amiodarone. ***Amiodarone*** - **First-line drug** for hemodynamically stable **monomorphic ventricular tachycardia (VT)**, as shown in the ECG. - **Class III antiarrhythmic** with superior efficacy compared to other agents for **VT termination** and prevention of recurrence. *Esmolol* - **Beta-blocker** primarily used for **rate control** in supraventricular tachycardia and atrial fibrillation. - **Not effective** for terminating ventricular tachycardia and may worsen hemodynamic status in VT. *Vernakalant* - **Specialized agent** for **acute cardioversion** of recent-onset atrial fibrillation (within 48 hours). - **No indication** for ventricular arrhythmias and specifically contraindicated in **ventricular tachycardia**. *Lignocaine* - **Class IB antiarrhythmic** that was previously used for VT but is now considered **second-line**. - **Less effective** than amiodarone for VT termination and has **higher failure rates** in clinical practice.

Q: What is the best treatment for multifocal atrial tachycardia?

Verapamil. **Explanation:** Multifocal Atrial Tachycardia (MAT) is a supraventricular arrhythmia characterized by a heart rate >100 bpm and at least three distinct P-wave morphologies in the same lead. It is most commonly associated with underlying pulmonary diseases, particularly **COPD** or acute respiratory failure. **Why Verapamil is the correct answer:** The primary management of MAT is treating the underlying cause (e.g., correcting hypoxia or hypercapnia). However, when pharmacological rate control is required, **Calcium Channel Blockers (Verapamil or Diltiazem)** are the drugs of choice [1]. Verapamil works by slowing conduction through the AV node and suppressing the ectopic atrial foci. **Why other options are incorrect:** * **DC Shock (A):** MAT is an irregular rhythm arising from multiple foci, not a re-entrant circuit. Therefore, electrical cardioversion is ineffective and contraindicated. * **Amiodarone (B):** While it has anti-arrhythmic properties, it is not the first-line treatment for MAT and carries a higher risk of toxicity compared to CCBs [1]. * **Beta-blockers (D):** Although they can control the rate, they are generally **avoided** because MAT is frequently associated with severe COPD/Asthma, where beta-blockers can precipitate bronchospasm [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Diagnostic Triad:** HR >100 bpm, ≥3 different P-wave shapes, and irregular P-P intervals. * **Wandering Atrial Pacemaker (WAP):** Same ECG findings as MAT but with a heart rate <100 bpm. * **The

Q: What percentage of critical narrowing of coronary blood vessels is generally considered significant?

70%. In clinical cardiology, the significance of coronary artery stenosis is defined by its impact on blood flow and oxygen delivery to the myocardium. **1. Why 70% is Correct:** A coronary artery narrowing is generally considered **"critically significant"** when the luminal diameter is reduced by **70% or more**. At this threshold, the vessel's ability to increase blood flow during periods of increased myocardial oxygen demand (exercise or stress) is severely compromised, leading to **exertional angina**. While resting flow is usually maintained until the stenosis reaches approximately 90%, the "70% rule" is the standard threshold for defining obstructive Coronary Artery Disease (CAD) and considering revascularization (PCI or CABG) [1]. **2. Analysis of Incorrect Options:** * **60% (Option B):** While a 50–60% stenosis is considered "moderate," it often does not limit flow enough to cause symptoms under normal stress conditions [2]. * **80% & 90% (Options C & D):** These represent severe stenosis [2]. While definitely significant, they are beyond the *initial* threshold of 70% used to define critical narrowing. A 90% stenosis is specifically associated with the loss of resting flow autoregulation, leading to symptoms even at rest [1]. **3. Clinical Pearls for NEET-PG:** * **Left Main Exception:** For the **Left Main Coronary Artery (LMCA)**, a narrowing of **≥50%** is considered clinically significant due to the vast amount of myocardium it supplies. * **Functional Assessment:** If a lesion is borderline (e.g., 50-70%), **Fractional Flow Reserve (FFR)** is used. An **FFR < 0.80** indicates a hemodynamically significant lesion requiring intervention. * **Gold Standard:** Coronary Angiography (CAG) remains the gold standard for anatomical assessment, but FFR is the gold standard for functional assessment.

Q: A 45-year-old man presents with exertional dyspnea and pitting pedal edema. His neck veins are dilated. A diagnosis of superior vena cava (SVC) syndrome is made. What is the next diagnostic step?

Perform a CT scan of the chest. Superior Vena Cava (SVC) syndrome is a clinical emergency caused by the obstruction of blood flow through the SVC, most commonly due to extrinsic compression by a mediastinal mass. In adults, approximately **60–90% of cases are caused by malignancies**, with Bronchogenic Carcinoma (especially Small Cell Lung Cancer) being the most frequent, followed by Lymphoma. **1. Why Option B is correct:** Once SVC syndrome is clinically suspected (dilated neck veins, facial puffiness, dyspnea), the immediate priority is to **confirm the diagnosis and identify the cause**. A **Contrast-Enhanced CT (CECT) scan of the chest** is the gold standard initial diagnostic step [1]. It provides detailed information regarding the site and severity of obstruction, identifies the underlying mass, and helps plan further interventions like biopsy or stenting [1]. **2. Why other options are incorrect:** * **Option A:** While a blood count may show leukocytosis or abnormal cells in leukemia, it is non-specific and does not provide anatomical information about the obstruction. * **Options C & D:** These are therapeutic interventions. Treatment (Chemotherapy or Radiotherapy) should **never** be initiated before establishing a tissue diagnosis (biopsy), unless there is life-threatening airway obstruction or cerebral edema. **Clinical Pearls for NEET-PG:** * **Most common cause:** Bronchogenic Carcinoma. * **Most common benign cause:** Retrosternal Goiter (historically Syphilitic Aneurysm) [1]. * **Pemberton’s Sign:** Facial flushing and inspiratory stridor upon raising both arms; indicates a retrosternal mass compressing the SVC. * **Management:** Elevate the head of the bed, oxygen, and diuretics for symptomatic relief while awaiting definitive diagnosis via CT-guided or bronchoscopic biopsy.

Q: Atrial myxoma is associated with which of the following clinical manifestations, except?

Systolic murmur at apex. Atrial myxoma is the most common primary cardiac tumor, typically located in the left atrium (75%). It presents with a classic triad of **constitutional symptoms**, **embolic phenomena**, and **obstructive features**. **Why "Systolic murmur at apex" is the correct (except) answer:** Left atrial myxomas typically mimic **Mitral Stenosis**, not mitral regurgitation. As the tumor prolapses into the mitral orifice during diastole, it causes an obstruction to blood flow, resulting in a **Mid-Diastolic Murmur** [1]. A characteristic "tumor plop" (a low-pitched sound heard shortly after S2) is often present. A systolic murmur would suggest mitral regurgitation [2], which is far less common than the obstructive diastolic murmur [3]. **Analysis of other options:** * **Fever & Weight loss (Options A & B):** Myxomas frequently produce **Interleukin-6 (IL-6)**, a pro-inflammatory cytokine. This leads to constitutional "flu-like" symptoms, including fever, weight loss, malaise, and elevated ESR/CRP, often mimicking systemic vasculitis or connective tissue disease. * **Subungual splinter haemorrhage (Option D):** Myxomas are friable. Fragmentation of the tumor or associated surface thrombi can lead to systemic embolization. This can manifest as strokes, peripheral arterial occlusion, or stigmata mimicking infective endocarditis, such as splinter hemorrhages. **High-Yield NEET-PG Pearls:** * **Most common site:** Fossa ovalis in the Left Atrium. * **Diagnosis:** Echocardiography is the gold standard (shows a pedunculated mobile mass). * **Carney Complex:** An autosomal dominant syndrome (PRKAR1A gene) involving atrial myxomas, skin hyperpigmentation (lentigines), and endocrine overactivity. * **Positional Variation:** Symptoms and murmurs may change characteristically with the patient's body position.

Q: Left axis deviation is seen in all except?

ASD (Septum secundum). The standard range for a normal cardiac axis is **-30° to +90°** [1]. Left Axis Deviation (LAD) is defined as an axis more negative than -30° [1]. **Why ASD (Septum Secundum) is the correct answer:** Atrial Septal Defect (ASD) of the **Ostium Secundum** type typically causes volume overload of the right ventricle, leading to **Right Axis Deviation (RAD)** and Right Bundle Branch Block (RBBB). In contrast, ASD **Ostium Primum** is a classic cause of Left Axis Deviation. This distinction is a high-yield "favorite" in postgraduate exams. **Analysis of other options:** * **Left Anterior Hemiblock (LAHB):** This is the most common cause of LAD. Since the anterior fascicle is blocked, depolarization spreads superiorly and to the left, shifting the axis. * **Inferior Wall MI:** Dead myocardial tissue in the inferior wall is electrically silent. The vector of depolarization points away from the infarcted area (upwards), resulting in a "pathological" LAD. * **Right Pneumothorax:** A large pneumothorax can physically shift the mediastinum and the heart toward the left side, resulting in a leftward shift of the QRS axis. **High-Yield Clinical Pearls for NEET-PG:** 1. **LAD Causes:** Left Anterior Hemiblock, LVH (variable), Inferior Wall MI, WPW Syndrome (Right-sided bypass tract), and **ASD Ostium Primum**. 2. **RAD Causes:** Right Ventricular Hypertrophy (RVH), Lateral Wall MI, Pulmonary Embolism, and **ASD Ostium Secundum**. 3. **Mnemonic:** "Primum = Premium (Left/Top)", "Secundum = Second (Right/Bottom)". This helps remember that Primum causes LAD and Secundum causes RAD.

Q: What is the most common cardiac arrhythmia?

Atrial fibrillation. **Explanation:** **Atrial Fibrillation (AF)** is the correct answer as it is globally recognized as the most common sustained cardiac arrhythmia in clinical practice [1]. Its prevalence increases significantly with age, affecting approximately 10% of individuals over the age of 80 [1]. The underlying pathophysiology involves multiple re-entrant wavelets or focal triggers (most commonly originating from the **pulmonary veins**) that lead to disorganized atrial electrical activity and an "irregularly irregular" ventricular response [1]. **Analysis of Incorrect Options:** * **Inappropriate Sinus Tachycardia (IST):** This is a relatively rare condition characterized by an elevated resting heart rate or disproportionate response to exertion without an underlying cause. It is far less common than AF. * **Premature Junctional Complexes (PJCs):** While these are common ectopics, they are usually transient and do not constitute a sustained rhythm disorder like AF [2]. * **Atrial Flutter:** Although it shares similar risk factors with AF, it is significantly less common. It is characterized by a "saw-tooth" pattern on ECG and is caused by a large re-entrant circuit, typically around the tricuspid annulus (macro-reentry) [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Most common cause:** Hypertension and Valvular Heart Disease (Mitral Stenosis). * **ECG Hallmark:** Absence of P-waves and "irregularly irregular" R-R intervals. * **Management:** The primary goals are rate control (Beta-blockers/CCBs), rhythm control (Amiodarone/Flecainide), and **anticoagulation** (based on CHADS₂-VASc score) to prevent embolic stroke [1]. * **Ashman Phenomenon:** A long R-R interval followed by a short R-R interval resulting in an aberrantly conducted QRS complex, often seen in AF.

Q: Which of the following cardiac rhythms is NOT associated with hyperkalemia?

Torsades de pointes. Explanation: **Hyperkalemia** affects cardiac conduction by partially depolarizing the resting membrane potential, which decreases the excitability of the myocardium and slows impulse conduction [1]. **Why Torsades de pointes is the correct answer:** Torsades de pointes (TdP) is a specific form of polymorphic ventricular tachycardia associated with a **prolonged QT interval** [2]. It is characteristically caused by **hypokalemia**, hypomagnesemia, and hypocalcemia—not hyperkalemia [3]. Hyperkalemia typically causes a *shortened* QT interval due to rapid repolarization (manifesting as tall, peaked T waves) [1]. **Analysis of incorrect options:** * **Sinus Bradycardia & Sinus Arrest:** As potassium levels rise, the sinoatrial (SA) node becomes depressed. This leads to bradycardia and, eventually, sinus arrest or "sine wave" rhythms as the P-wave disappears due to atrial paralysis [1]. * **Ventricular Fibrillation:** Severe hyperkalemia (typically >8.0 mEq/L) leads to profound conduction delays and increased myocardial irritability, which can degenerate into ventricular tachycardia or ventricular fibrillation, leading to cardiac arrest [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Sequential ECG changes in Hyperkalemia:** Tall peaked T waves (earliest) → Prolonged PR interval → Loss of P waves (Atrial paralysis) → Widening of QRS complex → Sine wave pattern → Asystole/V-Fib [1]. * **Treatment Priority:** Intravenous **Calcium Gluconate** is the first-line treatment to stabilize the cardiac membrane (it does not lower K+ levels). * **Rule of Thumb:** "Hypo" (K, Mg, Ca) prolongs the QT; "Hyper" (K, Ca) shortens the QT.

Question 1

What is the best drug for the rhythm disorder shown below?

Accepted Answer

Amiodarone

Answer

Esmolol

Answer

Vernakalant

Answer

Lignocaine

Question 2

What is the best treatment for multifocal atrial tachycardia?

Accepted Answer

Verapamil

Answer

DC shock

Answer

Amiodarone

Answer

Beta blocker

Question 3

What percentage of critical narrowing of coronary blood vessels is generally considered significant?

Accepted Answer

70%

Answer

60%

Answer

80%

Answer

90%

Question 4

Pulsus paradoxus is present in all of the following conditions EXCEPT:

Accepted Answer

Hypertrophic cardiomyopathy

Answer

Emphysema

Answer

Pulmonary embolism

Answer

Hypovolemic shock

Question 5

A 45-year-old man presents with exertional dyspnea and pitting pedal edema. His neck veins are dilated. A diagnosis of superior vena cava (SVC) syndrome is made. What is the next diagnostic step?

Accepted Answer

Perform a CT scan of the chest

Answer

Perform a total blood count and peripheral smear

Answer

Initiate cyclophosphamide therapy

Answer

Initiate radiotherapy

Question 6

Atrial myxoma is associated with which of the following clinical manifestations, except?

Accepted Answer

Systolic murmur at apex

Answer

Fever

Answer

Weight loss

Answer

Subungual splinter haemorrhage

Question 7

Left axis deviation is seen in all except?

Accepted Answer

ASD (Septum secundum)

Answer

Left anterior hemi block

Answer

Inferior wall MI

Answer

Right pneumothorax

Question 8

A 22-year-old woman presents with sharp chest pain, exacerbated by lying down, especially on her left side. One week prior, she experienced flu-like symptoms with fevers, chills, and myalgias. Her past medical history is negative, and she takes no medications. On physical examination, blood pressure is 130/80 mm Hg, heart rate is 100/min, with no pulsus paradoxus. Heart sounds are normal, but a pericardial rub is heard best at the apex in the left lateral decubitus position. Lungs are clear, and there is no peripheral edema. Which of the following features determines the patient's clinical course and prognosis?

Accepted Answer

Presence or nature of any underlying disease

Answer

Specific gravity of the fluid

Answer

Presence or absence of blood in the fluid

Answer

Cellular count of the fluid

Question 9

What is the most common cardiac arrhythmia?

Accepted Answer

Atrial fibrillation

Answer

Inappropriate sinus tachycardia

Answer

Premature junctional complexes

Answer

Atrial flutter

Question 10

Which of the following cardiac rhythms is NOT associated with hyperkalemia?

Accepted Answer

Torsades de pointes

Answer

Sinus arrest

Answer

Sinus bradycardia

Answer

Ventricular fibrillation

Cardiology — MCQs

Cardiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?