NEET-PG 2017 - Internal Medicine PYQs 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 Internal Medicine PYQs 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 Internal Medicine PYQs 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 Internal Medicine PYQs on OnCourse]

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

Prolonged QT interval. ***Prolonged QT interval*** - A patient who has undergone thyroidectomy and presents with muscle cramps likely has **hypocalcemia** due to inadvertent parathyroid gland removal. - Hypocalcemia is well-known to cause a **prolonged QT interval** on EKG, increasing the risk of arrhythmias. *Short QT interval* - A short QT interval is typically associated with **hypercalcemia** or genetic disorders. - This patient's presentation of muscle cramps is inconsistent with hypercalcemia. *ST elevation* - ST elevation is a hallmark of **acute myocardial infarction** or **pericarditis**. - This finding is unrelated to hypocalcemia or the patient's immediate postoperative and symptoms. *ST depression* - ST depression often indicates **myocardial ischemia** or **digoxin effect**. - It is not a characteristic ECG change associated with hypocalcemia or muscle cramps. [Practice more Internal Medicine PYQs on OnCourse]

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

Non paroxysmal atrial tachycardia with regular AV block. ***Non paroxysmal atrial tachycardia with regular AV block*** - The ECG shows a sustained atrial tachycardia with a **consistent P-P interval**, indicating a non-paroxysmal origin. - There is a **fixed ratio between P waves and QRS complexes** (e.g., 2:1 or 3:1), demonstrating a regular AV block, likely due to increased vagal tone or AV nodal dysfunction, often seen in cases of **digoxin toxicity** (given the patient is on heart failure treatment for valvular heart disease). *Tall tented T-wave* - **Tall, tented T-waves** are characteristic of **hyperkalemia**, but the ECG tracing does not exhibit this morphology. - While hyperkalemia can cause rhythm disturbances, the predominant feature here is a regular atrial tachycardia with AV block, not T-wave changes typical of electrolyte imbalance. *Ventricular bigeminy* - **Ventricular bigeminy** would manifest as alternating normal QRS complexes with premature ventricular contractions (PVCs). - The ECG shows a narrow complex tachycardia with visible P waves, which are not characteristic of PVCs or ventricular bigeminy. *Non paroxysmal atrial tachycardia with irregular AV block* - Although there is non-paroxysmal atrial tachycardia, the **AV block is regular** (e.g., a consistent 2:1 or 3:1 conduction ratio), not irregular. - An irregular AV block would suggest variability in AV nodal conduction, such as in AV Wenckebach or Mobitz type II with variable conduction, which is not what is seen in this tracing. [Practice more Internal Medicine PYQs 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 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 5

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 6

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

Question 7

The patient with the following hematological abnormality presents with severe chest pain and difficulty in breathing. All are useful for managing this emergency except:

Accepted Answer

Packed RBC

Answer

Partial exchange transfusion

Answer

Morphine

Answer

Hydroxyurea

Question 8

MRI was performed on a 35-year-old man with progressive myoclonus and apathy. What is the diagnosis? (Recent NEET Pattern 2016-17)

Accepted Answer

Prion disease

Answer

Herpes simplex encephalitis

Answer

SSPE

Answer

Mesial temporal sclerosis

Question 9

A 35-year-old woman presents with thunderclap headache. NCCT was done. All are true about the condition except:

Accepted Answer

Most common cause of death is rebleeding

Answer

Hyponatremia

Answer

Prolonged QT interval

Answer

Nimodipine is drug of choice

Question 10

Identify the lesion. (Recent NEET Pattern 2016-17)

Accepted Answer

Right supranuclear lesion

Answer

Left supranuclear lesion

Answer

Right infranuclear lesion

Answer

Left infranuclear lesion

NEET-PG 2017 — Internal Medicine