Cardiology Practice Questions

Q: The normal P wave is inverted in which lead?

Lead aVR. **Explanation:** The direction of the P wave on an ECG is determined by the vector of atrial depolarization. In a normal heart, the electrical impulse originates in the SA node (located in the high right atrium) and travels downwards and to the left toward the AV node [1]. **Why Lead aVR is correct:** Lead aVR is an augmented limb lead positioned on the right shoulder. Since the atrial depolarization vector moves **away** from the right shoulder (downward and leftward), the electrical activity is recorded as a negative deflection [1]. Therefore, a normal sinus P wave is **always inverted in lead aVR**. **Why the other options are incorrect:** * **Lead I:** This lead looks from the right arm to the left arm. Since the vector moves toward the left, the P wave is positive. * **Lead II:** This lead follows the primary axis of the heart (from right shoulder to left leg). Because the vector moves directly toward this lead, Lead II typically shows the **tallest and most upright** P wave [1]. * **Lead aVF:** This is an inferior lead looking upward from the feet. Since the vector moves downward toward the feet, the P wave is positive. **High-Yield Clinical Pearls for NEET-PG:** * **Sinus Rhythm Criteria:** A rhythm is defined as "sinus" only if the P wave is upright in leads I, II, and aVF, and inverted in aVR. * **Dextrocardia/Lead Reversal:** If you see an **upright P wave in aVR** and an inverted P wave in Lead I, suspect either limb lead reversal (most common) or Dextrocardia. * **Biphasic P waves:** The P wave may be biphasic in lead **V1**, where the initial positive deflection represents right atrial activity and the terminal negative deflection represents left atrial activity.

Q: Severity of mitral stenosis is determined by:

Diastolic murmur duration. ### Explanation The severity of Mitral Stenosis (MS) is primarily determined by the **duration of the diastolic murmur**, not its intensity. [2] **1. Why "Diastolic Murmur Duration" is correct:** In MS, the mid-diastolic murmur occurs due to a pressure gradient between the left atrium (LA) and left ventricle (LV). As the mitral valve orifice narrows (increased severity), it takes longer for the LA to empty into the LV. Consequently, the LA pressure remains higher than the LV pressure for a longer portion of diastole. Therefore, the **longer the duration** of the murmur (i.e., the closer it extends toward the S1), the more severe the stenosis. **2. Why other options are incorrect:** * **Intensity of S1:** While S1 is loud in mild-to-moderate MS due to mobile leaflets, it actually becomes **soft or muffled** in severe, calcified MS. Thus, intensity does not linearly correlate with severity. [2] * **Opening Snap (OS):** The presence of an OS indicates mobile leaflets. However, severity is determined by the **A2-OS interval**, not the OS itself. A shorter A2-OS interval indicates higher LA pressure and more severe MS. [1] * **Intensity of Diastolic Murmur:** Murmur intensity depends on the flow rate and pressure gradient. In very severe MS with low cardiac output, the murmur may actually become very soft (Silent MS). **Clinical Pearls for NEET-PG:** * **Signs of Severe MS:** Long diastolic murmur, short A2-OS interval (<0.07s), presence of pulmonary hypertension (loud P2), and a small pulse pressure. [1] * **The "Silent MS":** Occurs when the valve area is so small and cardiac output so low that the murmur is barely audible. * **Most common cause:** Rheumatic heart disease. * **Gold Standard for Diagnosis:** Echocardiography (Planimetry is the most accurate for valve area). [3]

Q: What does the abbreviation AED stand for?

Automated external defibrillator. **Explanation:** The correct term is **Automated External Defibrillator (AED)**. An AED is a portable, computerized medical device designed to be used by both medical professionals and laypeople during a cardiac arrest. It automatically analyzes the patient’s cardiac rhythm (specifically looking for shockable rhythms like Ventricular Fibrillation or Pulseless Ventricular Tachycardia) and delivers an electric shock to restore a functional heart rhythm [1]. **Analysis of Options:** * **Option B (Correct):** "Automated" is the precise term because the device uses internal algorithms to autonomously diagnose the rhythm and determine if a shock is indicated. "External" refers to the application of pads on the chest skin, as opposed to internal paddles used in surgery. * **Option A:** "Automatic" is a common misnomer. While the device performs tasks automatically, the official medical and manufacturing nomenclature is "Automated." * **Options C & D:** "Electrical" is redundant and incorrect in the title. While the device delivers an electrical current, the standard terminology focuses on its "External" application. **Clinical Pearls for NEET-PG:** 1. **Shockable Rhythms:** AEDs are programmed to recognize only two rhythms: **Ventricular Fibrillation (VF)** and **Pulseless Ventricular Tachycardia (pVT)** [1]. 2. **Non-shockable Rhythms:** Asystole and Pulseless Electrical Activity (PEA) [1]. In these cases, the AED will advise "No shock indicated," and CPR should be resumed immediately. 3. **Chain of Survival:** Early defibrillation is the most critical factor in improving survival rates for out-of-hospital cardiac arrest (OHCA) [1]. 4. **Safety:** Always ensure the patient is not in water and the chest is dry before applying AED pads to prevent electrical arcing.

Q: Romana's sign is seen in which of the following?

Trypanosoma cruzi. **Explanation:** **Romaña’s sign** is a classic clinical hallmark of **Acute Chagas Disease**, caused by the protozoan parasite ***Trypanosoma cruzi***. It occurs when the parasite (transmitted via the feces of the Triatomine or "kissing" bug) enters through the conjunctiva or the skin near the eye. 1. **Why Trypanosoma cruzi is correct:** Romaña’s sign is characterized by **painless, unilateral periorbital edema**, conjunctivitis, and local lymphadenopathy (pre-auricular nodes). It represents the portal of entry for the parasite. If the parasite enters through a skin break elsewhere, the resulting inflammatory lesion is called a **Chagoma**. 2. **Why other options are incorrect:** * **Toxoplasma:** Typically presents with lymphadenopathy or chorioretinitis in immunocompromised hosts, but does not cause Romaña’s sign. * **Loa loa:** Known for **Calabar swellings** (transient, itchy dermal swellings) and the visible migration of the adult worm across the subconjunctiva [1]. * **Wuchereria bancrofti:** Causes lymphatic filariasis, leading to elephantiasis and hydrocele, but not acute periorbital edema. **High-Yield Clinical Pearls for NEET-PG:** * **Vector:** Triatomine bug (Reduviid bug). * **Chronic Chagas Disease:** Characterized by "Mega-syndromes"—**Dilated Cardiomyopathy** (most common cause in South America), **Megaesophagus**, and **Megacolon** [2]. * **ECG Finding:** Right Bundle Branch Block (RBBB) is a common conduction defect in Chagasic heart disease. * **Treatment:** Benznidazole or Nifurtimox [2].

Q: Brugada syndrome is characterized by what ECG finding?

ST elevation. Explanation: Brugada Syndrome is an autosomal dominant genetic disorder caused by a mutation in the SCN5A gene, which encodes the cardiac sodium channel. This leads to a defect in the inward sodium current, primarily affecting the right ventricular outflow tract (RVOT). Why ST elevation is correct: The hallmark ECG finding in Brugada Syndrome is coved-type ST-segment elevation (≥2 mm) followed by a negative T-wave in the right precordial leads (V1–V3). This is known as the Type 1 Brugada pattern. It is often described as having a "shark fin" or "saddle-back" appearance. These changes occur due to an imbalance between inward and outward currents during the early repolarization phase of the action potential. Why other options are incorrect: * Prolonged PR interval: Associated with first-degree AV block or conditions like hyperkalemia and Lyme disease [3], but not the diagnostic hallmark of Brugada. * Prolonged QT interval: Characteristic of Long QT Syndrome (LQTS), which predisposes to Torsades de Pointes [2]. Brugada typically has a normal QT interval. * Tall T waves: Usually seen in hyperkalemia (peaked T waves) [3] or the hyperacute phase of myocardial infarction [1]. High-Yield Clinical Pearls for NEET-PG: * Demographics: Most common in young males of Southeast Asian descent. * Clinical Presentation: Sudden cardiac death (SCD) due to polymorphic ventricular tachycardia or ventricular fibrillation, often occurring during sleep or while at rest. * Triggers: Fever, alcohol, and certain drugs (e.g., sodium channel blockers) can unmask the ECG pattern. * Management: The only proven effective treatment for symptomatic patients or those at high risk is an Implantable Cardioverter Defibrillator (ICD).

Q: Which of the following is a BNP analogue?

Nesiritide. **Explanation:** **Correct Answer: B. Nesiritide** Nesiritide is a **recombinant human B-type Natriuretic Peptide (BNP)**. It works by binding to the particulate guanylate cyclase receptor in vascular smooth muscle and endothelial cells, leading to increased intracellular cyclic GMP (cGMP) [1]. This results in potent **vasodilation** (reducing both preload and afterload) and **natriuresis** (excretion of sodium by the kidneys) [1], [2]. It is primarily used in the management of acutely decompensated heart failure (ADHF) with dyspnea at rest. **Analysis of Incorrect Options:** * **A. Eplerenone:** This is a selective **mineralocorticoid receptor antagonist (MRA)**. It is a potassium-sparing diuretic used to reduce mortality in chronic heart failure (HFrEF), but it is not a BNP analogue. * **C. Levosimendan:** This is a **calcium sensitizer** and an inodilator. It increases cardiac contractility by sensitizing troponin C to calcium and causes vasodilation by opening ATP-sensitive potassium channels. * **D. Coenzyme Q:** This is an antioxidant and a component of the mitochondrial electron transport chain. While sometimes used as a supplement in heart failure, it has no structural or functional relation to BNP. **High-Yield Clinical Pearls for NEET-PG:** * **BNP vs. NT-proBNP:** BNP is the active hormone (shorter half-life), while NT-proBNP is the inactive N-terminal fragment (longer half-life, more stable for diagnostic testing). * **Sacubitril/Valsartan (ARNI):** Sacubitril is a **neprilysin inhibitor** that prevents the breakdown of endogenous BNP. Note that BNP levels will rise during ARNI therapy, so NT-proBNP should be used for monitoring instead. * **Nesiritide Side Effects:** The most common side effect is dose-related **hypotension**. It may also be associated with a transient increase in serum creatinine.

Q: Which of the following findings may be seen in a second-degree heart block?

All of the above. **Explanation:** Second-degree heart block is characterized by intermittent failure of the AV node or His-Purkinje system to conduct atrial impulses to the ventricles. This leads to specific ECG changes that validate all the given options. 1. **Atrial rate more than ventricular rate (Option B):** This is the hallmark of second-degree block. Because some P waves are "dropped" (not followed by a QRS complex), there are more P waves than QRS complexes, making the atrial rate higher than the ventricular rate. 2. **Prolonged conduction time (Option C):** In **Mobitz Type I (Wenckebach)**, there is progressive prolongation of the PR interval until a beat is dropped. Even in **Mobitz Type II**, the underlying conduction system disease often results in a baseline prolonged PR interval or delayed conduction through the bundle branches. 3. **Change in QRS complex morphology (Option A):** This is particularly relevant in **Mobitz Type II** block. This type usually occurs infra-nodally (at the Bundle of His or Purkinje fibers). It is frequently associated with a **wide QRS complex** (Bundle Branch Block), whereas Mobitz Type I usually presents with a narrow QRS. **High-Yield Clinical Pearls for NEET-PG:** * **Mobitz Type I (Wenckebach):** Site of block is usually the **AV Node**. It is often reversible, associated with increased vagal tone or inferior wall MI, and usually has a benign prognosis. * **Mobitz Type II:** Site of block is **infra-nodal**. It is more dangerous as it can suddenly progress to Complete Heart Block (3rd degree). It often requires a permanent pacemaker. * **Vagal Maneuvers:** Carotid sinus massage worsens Mobitz Type II but may improve Mobitz Type I.

Question 1

The normal P wave is inverted in which lead?

Accepted Answer

Lead aVR

Answer

Lead I

Answer

Lead II

Answer

Lead aVF

Question 2

Severity of mitral stenosis is determined by:

Accepted Answer

Diastolic murmur duration

Answer

Intensity of S1 heart sound

Answer

Opening snap

Answer

Intensity of diastolic murmur

Question 3

What does the abbreviation AED stand for?

Accepted Answer

Automated external defibrillator

Answer

Automatic external defibrillator

Answer

Automatic electrical defibrillator

Answer

Automated electrical defibrillator

Question 4

Romana's sign is seen in which of the following?

Accepted Answer

Trypanosoma cruzi

Answer

Toxoplasma

Answer

Loaloa

Answer

Wuchereria

Question 5

Brugada syndrome is characterized by what ECG finding?

Accepted Answer

ST elevation

Answer

Prolonged PR interval

Answer

Prolonged QT interval

Answer

Tall T waves

Question 6

A 70-year-old man with hypertension presents with severe chest pain and diaphoresis. On examination, he has bounding pulses with wide pulse pressure. A diastolic murmur is heard along the right sternal border. Which of the following is the possible etiology?

Accepted Answer

Aortic dissection

Answer

STEMI with papillary muscle dysfunction

Answer

Myocarditis with functional regurgitation

Answer

Flash pulmonary edema

Question 7

A 60-year-old woman with no past medical history has an elevated blood pressure of 165/80 mm Hg on routine evaluation. Repeated measurements over the next month confirm the elevated pressure. Physical examination, routine blood count, and biochemistry are all normal. For a patient with high blood pressure, select the most appropriate initial medication?

Accepted Answer

Thiazide diuretics

Answer

Spironolactone

Answer

Clonidine

Answer

Prazosin

Question 8

Which of the following is a BNP analogue?

Accepted Answer

Nesiritide

Answer

Eplerenone

Answer

Levosimendan

Answer

Coenzyme Q

Question 9

A gradient between pulmonary artery wedge pressure and left ventricular end-diastolic pressure is seen in which of the following conditions?

Accepted Answer

Left atrial myxoma

Answer

Aortic regurgitation

Answer

Constrictive pericarditis

Answer

Pulmonary thromboembolism

Question 10

Which of the following findings may be seen in a second-degree heart block?

Accepted Answer

All of the above

Answer

Change in QRS complex morphology

Answer

Atrial rate more than ventricular rate

Answer

Prolonged conduction time

Cardiology — MCQs

Cardiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?