Here are the correct answers for each question on this pharmacology exam about antiarrhythmic drugs:

Patient R., 48 years old — post-MI, sinus tachycardia, frequent ventricular extrasystoles, BP 100/60 mmHg. Prescribed: Obzidan (propranolol) 160 mg/day + Sustak-Forte + Panangin + Riboxin. What side effect is likely?

✅ Correct Answer: 3. Hypotension, dizziness

Rationale: Obzidan (propranolol, a non-selective beta-blocker) at 160 mg/day combined with Sustak-Forte (isosorbide dinitrate, a nitrate vasodilator) will cause additive vasodilation and hypotension. Both agents lower blood pressure — propranolol by reducing cardiac output, nitrates by venodilation — making hypotension and dizziness the most predictable adverse effect of this combination.

Patient R., 56 years old — post-MI, BP 130/90 mmHg, sinus tachycardia, isolated ventricular extrasystoles. Choose an antiarrhythmic drug.

✅ Correct Answer: 1. Bisoprolol

Rationale: Bisoprolol is a cardioselective beta-1 blocker — the first-line antiarrhythmic for post-MI ventricular extrasystoles with concurrent hypertension and tachycardia. It reduces sympathetic drive, heart rate, and ectopic activity. Amlodipine (option 2) treats hypertension but not ventricular arrhythmias. Atropine (3) and lidocaine (4) are acute IV drugs, not oral management. Ethacizine (5) is a class IC agent with proarrhythmic risk, contraindicated post-MI.

Patient K., 26 years old — paroxysmal sinus tachycardia at 170 bpm, sudden onset, no structural heart disease (clear heart sounds, BP 130/80). What is your tactic?

✅ Correct Answer: 4. Isoptin 2.5%–4 ml + physical solution 10, i.v., jet

Rationale: Paroxysmal supraventricular tachycardia (SVT) in a young patient without structural disease is best terminated with IV verapamil (Isoptin). Verapamil blocks AV nodal conduction, breaking the re-entry circuit. Lidocaine (1) is for ventricular arrhythmias. Atropine (2) increases heart rate — contraindicated here. Kordaron/amiodarone (3) is used but is second-line in acute SVT. Novocainamide (5) IM is slower and less appropriate for acute SVT.

Patient S., 39 years old — severe weakness, heaviness in the heart, dyspnea. ECG: sinus rhythm at 49 bpm (bradycardia). What is your tactic?

✅ Correct Answer: 2. Atropine 0.1%–0.5 ml / m (i.m./i.v.)

Rationale: Sinus bradycardia at 49 bpm is treated with atropine, an anticholinergic that blocks vagal tone and increases heart rate. Isoptin/verapamil (1) would worsen bradycardia — contraindicated. Amiodarone (3) and lidocaine (4) are for tachyarrhythmias. Novocainamide (5) slows conduction and is also contraindicated in bradycardia.

Patient S., 72 years old — acute anterior-lateral MI with ST elevation, frequent ventricular extrasystoles in bigemy pattern, BP 100/70 mmHg, HR 100 bpm, cyanosis, positive troponin.

✅ Correct Answer: 1. Promedol 1% 1 ml i.m. + Heparin 5000 U IV jet + Aspirin 1 tab chew + Isosorbide dinitrate 10.0 per physical solution + Lidocaine 2%–5 ml IV

Rationale: This is an acute STEMI with ventricular arrhythmia (bigemy). The correct approach:

Option 2 uses bisoprolol orally — inappropriate acutely with BP 100/70 (hypotension risk). Option 4 lacks heparin. Option 5 lacks lidocaine for the ventricular arrhythmia.