Cardiology Practice Questions

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.

Q: J waves are typically seen in which of the following conditions?

Hypothermia. Explanation: J waves, also known as Osborn waves, are positive deflections occurring at the junction between the QRS complex and the ST segment (the J-point). 1. Why Hypothermia is Correct: Hypothermia is the classic cause of J waves. They typically appear when the core body temperature drops below 32°C (90°F). The physiological basis involves a temperature-sensitive gradient between the epicardium and endocardium during early ventricular repolarization, leading to a prominent notch at the J-point. The size of the J wave often correlates with the severity of the hypothermia. 2. Why Incorrect Options are Wrong: * Hyperthermia: Does not cause J waves; it is more commonly associated with sinus tachycardia or nonspecific ST-T changes [1]. * Hypokalemia: Characterized by U waves, flattened T waves, and ST-segment depression. * Hyperkalemia: Classically presents with tall, peaked "tented" T waves, widened QRS complexes, and loss of P waves [1]. 3. NEET-PG High-Yield Pearls: * Other causes of J waves: Hypercalcemia, Brugada syndrome, and early repolarization syndrome (normal variant). * ECG Triad of Hypothermia: 1. Sinus bradycardia (most common arrhythmia). 2. J waves (Osborn waves). 3. Prolonged PR, QRS, and QT intervals. * Artifact Alert: Shivering in hypothermic patients can cause a baseline artifact on ECG that mimics atrial flutter. * Management: Treatment focuses on active/passive rewarming rather than anti-arrhythmics, as J waves resolve with normalization of temperature.

Q: A bisferiens pulse is seen in all of the following conditions except?

Tetralogy of Fallot. ### Explanation A **bisferiens pulse** (from Latin *bis* meaning twice and *ferire* meaning to beat) is a physical finding characterized by two systolic peaks in the arterial pulse [3]. It is best palpated in the carotid or brachial arteries [3]. **1. Why Tetralogy of Fallot (TOF) is the correct answer:** In TOF, the primary hemodynamic issue is right-to-left shunting across a VSD and right ventricular outflow tract obstruction. This leads to a **diminished** or normal pulse volume, but not a double-peaked systolic pulse. Therefore, it is the "except" in this list. **2. Analysis of other options:** * **Aortic Stenosis with Aortic Regurgitation (AS + AR):** This is the classic cause. The first peak (percussion wave) is due to the rapid ejection of a large stroke volume (from AR), and the second peak (tidal wave) is caused by the obstruction and reflected waves (from AS). * **Aortic Regurgitation (AR):** Severe isolated AR can present with a bisferiens pulse due to the massive stroke volume being ejected rapidly into the aorta [2], followed by a momentary collapse and a second reflected wave. * **Hypertrophic Obstructive Cardiomyopathy (HOCM):** In HOCM, the pulse is "spike and dome." **3. NEET-PG High-Yield Pearls:** * **Pulsus Alternans:** Sign of severe Left Ventricular Failure (LVF). * **Pulsus Paradoxus:** Seen in Cardiac Tamponade, Severe Asthma, and COPD. * **Anacrotic Pulse:** Characteristic of isolated severe Aortic Stenosis [1]. * **Water-hammer Pulse:** Seen in isolated Aortic Regurgitation (large volume, rapid collapse) [2].

Q: What are the causes of a water-hammer pulse?

Both. ### Explanation A **water-hammer pulse** (also known as Corrigan’s pulse or a collapsing pulse) is characterized by a rapid upstroke and a sudden, forceful collapse [1]. The physiological basis for this is a **large stroke volume** coupled with a **rapid runoff** of blood from the arterial system into a low-pressure chamber or vessel during diastole. This leads to a wide pulse pressure. **Why Both A and B are Correct:** 1. **Patent Ductus Arteriosus (PDA):** In PDA, blood shunts from the high-pressure aorta into the low-pressure pulmonary artery during diastole. This "runoff" causes a rapid drop in diastolic blood pressure, while the increased venous return to the left heart increases stroke volume (systolic pressure), resulting in a wide pulse pressure and a collapsing pulse. 2. **Truncus Arteriosus:** This is a cyanotic congenital heart disease where a single large vessel overrides both ventricles. The presence of a large systemic-to-pulmonary shunt (similar to PDA) or associated truncal valve regurgitation leads to a rapid diastolic runoff into the pulmonary circulation, producing a water-hammer pulse. **Clinical Pearls for NEET-PG:** * **Most Common Cause:** Aortic Regurgitation (AR) is the classic cause cited in exams [1]. * **Other High-Yield Causes:** * **Hyperdynamic states:** Fever, Anemia, Thyrotoxicosis, Pregnancy, Beri-beri. * **Arteriovenous shunts:** Large AV fistulas, Paget’s disease of the bone. * **Cardiac:** Ruptured Sinus of Valsalva. * **Physical Exam Tip:** To best elicit a water-hammer pulse, palpate the patient's radial artery with the palm of your hand while elevating the patient's arm above the level of the heart. This accentuates the diastolic collapse due to gravity.

Q: A patient's history reveals dyspnea, orthopnea, and edema of the ankles and palpitations. What is the most likely diagnosis?

Congestive heart failure. **Explanation:** The patient presents with a classic triad of symptoms indicating **Congestive Heart Failure (CHF)**: pulmonary congestion (dyspnea, orthopnea) and systemic venous congestion (peripheral edema). [1] **1. Why Congestive Heart Failure is Correct:** CHF occurs when the heart cannot pump sufficient blood to meet metabolic demands. * **Left-sided failure** leads to pulmonary venous congestion, causing **dyspnea** and **orthopnea** (shortness of breath when lying flat, relieved by sitting up). [1] * **Right-sided failure** leads to systemic venous congestion, manifesting as dependent **pitting edema** of the ankles. * **Palpitations** often result from compensatory tachycardia or associated arrhythmias like Atrial Fibrillation, commonly seen in failing hearts. [1] **2. Why Other Options are Incorrect:** * **Respiratory problem:** While it causes dyspnea, it typically does not cause orthopnea (unless severe COPD/Asthma) or bilateral ankle edema (unless it leads to Cor Pulmonale). * **Hepatic failure:** May cause edema and ascites due to hypoalbuminemia and portal hypertension, but it rarely presents with orthopnea unless there is massive ascites limiting diaphragmatic movement. * **Uremia:** While chronic kidney disease causes fluid overload and edema, the primary presentation usually involves uremic symptoms (nausea, pruritus, encephalopathy) and does not specifically explain the orthopnea-palpitation complex as clearly as CHF. **NEET-PG High-Yield Pearls:** * **Framingham Criteria:** Used for clinical diagnosis of CHF (requires 2 major or 1 major + 2 minor criteria). Orthopnea is a **Major** criterion. * **Most sensitive sign:** Displaced apex beat. * **Most specific sign:** Third heart sound (S3 gallop). * **BNP (B-type Natriuretic Peptide):** High negative predictive value; used to rule out CHF in acute dyspnea. [1]

Q: What is considered a wide QRS duration?

Greater than 0.12 seconds. ### Explanation The QRS complex represents **ventricular depolarization**. In a healthy heart, electrical impulses travel rapidly through the specialized His-Purkinje system, ensuring synchronous ventricular contraction. **1. Why 0.12 seconds is correct:** A normal QRS duration is typically between **0.06 and 0.10 seconds** (1.5 to 2.5 small squares). A duration of **≥ 0.12 seconds** (3 small squares) is the standard diagnostic threshold for a **"Wide QRS."** This delay indicates that ventricular depolarization is occurring slowly, usually because the impulse is traveling through the working myocardium rather than the rapid conduction system [1]. **2. Why the other options are incorrect:** * **Options A and B (0.8 and 0.9 seconds):** These values are physiologically impossible for a single QRS complex. A duration of 0.8 seconds would mean a single heartbeat takes nearly a full second just to depolarize the ventricles, which is incompatible with life. These options likely confuse *seconds* with *milliseconds* (e.g., 80ms or 90ms), which fall within the normal range. * **Option D:** Since A and B are incorrect, "All the above" is invalid. **Clinical Pearls for NEET-PG:** * **Differential Diagnosis of Wide QRS:** 1. **Bundle Branch Blocks (RBBB/LBBB):** The most common cause. 2. **Ventricular Ectopy:** Premature Ventricular Contractions (PVCs) or Ventricular Tachycardia (VT) [2]. 3. **Pre-excitation:** Wolff-Parkinson-White (WPW) syndrome (due to the Delta wave) [1]. 4. **Metabolic/Toxic:** Hyperkalemia (classic "sine wave" appearance) or Sodium Channel Blocker toxicity (e.g., TCA overdose) [3]. 5. **Pacemaker-induced** rhythms. * **High-Yield Tip:** In the setting of tachycardia, a wide QRS should be considered **Ventricular Tachycardia** until proven otherwise [2].

Question 1

What is the most common cardiac arrhythmia?

Accepted Answer

Atrial fibrillation

Answer

Inappropriate sinus tachycardia

Answer

Premature junctional complexes

Answer

Atrial flutter

Question 2

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 3

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

Question 4

Which of the following conditions are typically associated with a continuous murmur?

Accepted Answer

Patent ductus arteriosus with reversal of shunt

Answer

Aortic stenosis combined with aortic regurgitation

Answer

Systemic arteriovenous fistula

Answer

Aortopulmonary window

Question 5

J waves are typically seen in which of the following conditions?

Accepted Answer

Hypothermia

Answer

Hyperthermia

Answer

Hypokalemia

Answer

Hyperkalemia

Question 6

Regarding Wolf-Parkinson-White (WPW) syndrome, which of the following statements is incorrect?

Accepted Answer

Type a is seen in association with Ebstein's anomaly.

Answer

There is a risk of ventricular tachycardia.

Answer

Presentation may be with hydrops fetalis.

Answer

Flecainide reduces the recurrence risk of tachycardias.

Question 7

A bisferiens pulse is seen in all of the following conditions except?

Accepted Answer

Tetralogy of Fallot

Answer

Aortic stenosis and aortic regurgitation

Answer

Aortic regurgitation

Answer

Hypertrophic cardiomyopathy

Question 8

What are the causes of a water-hammer pulse?

Accepted Answer

Both

Answer

Truncus arteriosus

Answer

Patent ductus arteriosus

Answer

None

Question 9

A patient's history reveals dyspnea, orthopnea, and edema of the ankles and palpitations. What is the most likely diagnosis?

Accepted Answer

Congestive heart failure

Answer

Respiratory problem

Answer

Hepatic failure

Answer

Uremia

Question 10

What is considered a wide QRS duration?

Accepted Answer

Greater than 0.12 seconds

Answer

Greater than 0.8 seconds

Answer

Greater than 0.9 seconds

Answer

All the above

Cardiology — MCQs

Cardiology — MCQs

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