NEET-PG 2017 Previous Year Questions Practice Questions

Q: Which of the following finding is shown in the chest leads?

Digoxin. ***Digoxin*** - The ECG shows a characteristic **downward sloping ST segment depression** with a "sagging" or "scooped" appearance, often referred to as a **"Salvador Dali mustache"** appearance, which is typical of digoxin effect on the ECG. - This pattern is due to the drug's effect on **myocardial repolarization**, specifically shortening the QT interval and inducing these ST changes, even in the absence of toxicity. *Myocardial ischemia* - Myocardial ischemia typically manifests as **ST segment depression** that is **horizontal** or **downsloping** but usually not with the characteristic "scooped" appearance seen with digoxin. - T-wave inversions may also be present, which are not the primary finding here. *Myocardial injury* - Acute myocardial injury is characterized by **ST segment elevation** (in acute myocardial infarction) or **significant ST depression with T-wave inversions** (in NSTEMI) which differs from the morphology seen in this ECG. - The morphology of the ST segment in myocardial injury is usually more abrupt and not "scooped" like a digoxin effect. *Digoxin toxicity* - While this ECG shows a digoxin effect, **digoxin toxicity** usually presents with **arrhythmias** (e.g., ventricular premature beats, bradycardia, AV blocks) in addition to altered ST-T wave morphology. - The ECG alone, showing only repolarization changes characteristic of digoxin, does not confirm toxicity without clinical correlation or evidence of arrhythmias. [Practice more NEET-PG 2017 questions on OnCourse]

Q: Cannon A waves are seen in the JVP of a patient. ECG shows:

Third degree heart block. ***Third degree heart block*** - **Cannon A waves** in the JVP occur when the right atrium contracts against a closed tricuspid valve, which happens when atrial and ventricular contractions are **dissociated** as seen in **complete heart block**. - In the provided ECG, there is complete dissociation between P waves (atrial activity) and QRS complexes (ventricular activity), with P waves occurring regularly but independently of the QRS complexes, which signifies a **third-degree (complete) heart block**. *First degree heart block* - Characterized by a **prolonged PR interval** (>0.20 seconds) where every P wave is followed by a QRS complex. - There is no dissociation of P waves and QRS complexes, and therefore no cannon A waves due to atrial contraction against a closed tricuspid valve. *Second degree heart block* - Involves some P waves not being followed by a QRS complex, indicating **intermittent conduction failure**. - There can be Wenckebach (Mobitz I) or Mobitz II, both of which involve some degree of P-wave-QRS coupling, usually not leading to constant or prominent cannon A waves. *Mobitz II heart block* - Defined by intermittently **dropped QRS complexes** without progressive PR lengthening, often with a constant PR interval before the drop. - While some dropped beats occur, there is still a clear relationship between the P waves and the conducted QRS complexes, which differs from the continuous and complete AV dissociation seen with cannon A waves in third-degree block. [Practice more NEET-PG 2017 questions on OnCourse]

Q: A patient develops missed beats after thrombolysis for MI. ECG shows:

Mobitz I heart block. ***Mobitz I heart block*** - The ECG shows a **progressive lengthening of the PR interval** before a QRS complex is dropped (missed beat), which is characteristic of Mobitz type I (Wenckebach) heart block. - This type of block is often **benign** and located in the AV node, frequently resolving spontaneously, especially after thrombolysis for an inferior MI. *Mobitz II heart block* - Characterized by **sudden, unexpected dropped QRS complexes** without prior PR interval lengthening. - Mobitz II usually indicates a block below the AV node (infranodal) and is considered more serious, often requiring a pacemaker. *Complete heart block* - In complete (third-degree) heart block, there is **no conduction between the atria and ventricles**, meaning P waves and QRS complexes are completely dissociated. - The ventricular rhythm is typically slow and independent of the atrial rhythm, which is not seen here as some P waves conduct. *Sick sinus syndrome* - Sick sinus syndrome is a **dysfunction of the SA node**, leading to various arrhythmias such as sinus bradycardia, sinus arrest, or sinoatrial block. - While it can cause missed beats, the ECG pattern here specifically points to a problem with AV conduction (PR interval changes and dropped QRS), not primary sinus node dysfunction. [Practice more NEET-PG 2017 questions on OnCourse]

Q: A 12-year-old child with renal tubular acidosis type I is having muscle cramps and weakness. ECG shows all except:

Absent P waves. ***Absent P waves*** - **Hypokalemia (low potassium)**, common in renal tubular acidosis type I, does not typically cause absent P waves. Absent P waves are characteristic of certain **atrial arrhythmias** or severe **hyperkalemia** with sine wave formation. - The image provided clearly shows visible P waves before each QRS complex, indicating **sinus rhythm** and normal atrial depolarization. *T wave inversion with U waves* - **Hypokalemia** can cause characteristic ECG changes including **T wave flattening**, **T wave inversion**, and prominent **U waves**, especially in leads V2-V4. - The provided ECG shows evidence of T wave flattening or inversion and visible U waves, which are consistent with hypokalemia. *ST depression* - **ST depression** can occur in cases of significant **hypokalemia**, particularly when potassium levels are very low. - The ECG shows some subtle **ST segment depression**, especially in leads like V3, which is a recognized finding in hypokalemia. *Heart rate of 75 beats per minute* - To calculate the heart rate, count the number of large squares between two R waves (e.g., in V5, there are approximately 4 large squares). The heart rate is 300 / number of large squares = 300 / 4 = **75 bpm**. - A heart rate of 75 bpm is a **normal sinus rhythm** and is not inconsistent with hypokalemia. [Practice more NEET-PG 2017 questions on OnCourse]

Question 1

Which of the following finding is shown in the chest leads?

Accepted Answer

Digoxin

Answer

Myocardial ischemia

Answer

Myocardial injury

Answer

Digoxin toxicity

Question 2

Cannon A waves are seen in the JVP of a patient. ECG shows:

Accepted Answer

Third degree heart block

Answer

First degree heart block

Answer

Second degree heart block

Answer

Mobitz II heart block

Question 3

A patient develops missed beats after thrombolysis for MI. ECG shows:

Accepted Answer

Mobitz I heart block

Answer

Mobitz II heart block

Answer

Complete heart block

Answer

Sick sinus syndrome

Question 4

A 12-year-old child with renal tubular acidosis type I is having muscle cramps and weakness. ECG shows all except:

Accepted Answer

Absent P waves

Answer

T wave inversion with U waves

Answer

ST depression

Answer

Heart rate of 75 beats per minute

Question 5

ECG of a patient had ST segment elevation in V1-V6, lead I and AVL. Which of the following branches is involved?

Accepted Answer

1

Answer

2

Answer

3

Answer

4

Answer

5

Question 6

A 35-year-old lady has been diagnosed with anxiety neurosis by her psychiatrist. She came to you for second opinion. Comment on the diagnosis based on ECG.

Accepted Answer

WPW syndrome

Answer

Sinus tachycardia

Answer

Multifocal atrial tachycardia

Answer

Atrial fibrillation

Answer

Supraventricular tachycardia

Question 7

A 68-year-old postoperative patient who has undergone thyroidectomy presents with muscle cramps. ECG shows?

Accepted Answer

Prolonged QT interval

Answer

Short QT interval

Answer

ST elevation

Answer

ST depression

Question 8

The given ECG of a neonate born to a mother with SLE shows?

Accepted Answer

Complete heart block

Answer

Mobitz I heart block

Answer

Mobitz II heart block

Answer

Sick sinus syndrome

Question 9

A 10-year-old child with Valvular heart disease on heart failure treatment, has the following ECG tracing. What is the diagnosis?

Accepted Answer

Non paroxysmal atrial tachycardia with regular AV block

Answer

Tall tented T-wave

Answer

Ventricular bigeminy

Answer

Non paroxysmal atrial tachycardia with irregular AV block

Question 10

A 50-year-old woman with rheumatic heart disease is on medication for heart disease. She feels unwell for most part of the day. Which of the following medicine is responsible for the ECG changes shown below? (Recent NEET Pattern 2016-17)

Accepted Answer

Digoxin

Answer

ACE inhibitor

Answer

Diuretics

Answer

Ivabradine

NEET-PG 2017

General Medicine

Internal Medicine

Pediatrics

Pharmacology