A 64-year-old man is admitted to the hospital with palpitations and lightheadedness for the past several days. He has experienced palpitations previously, but recently they have seemed sustained and "uncomfortable." The patient has had no chest pain or shortness of breath. He has a history of coronary artery disease and prior percutaneous coronary interventions. He is treated with metoprolol, lisinopril, aspirin, clopidogrel, and rosuvastatin. Echocardiogram shows mild left ventricular dilation, a left ventricular ejection fraction of 30%, and no major valvular abnormality. Serum potassium is 4.2 mEq/L and magnesium is 1.9 mg/dL. On day 2 of hospitalization, the patient develops sudden-onset palpitations that feel like "fluttering in my chest." Blood pressure is 122/60 mm Hg. He is alert and does not appear to be in distress. Examination shows clear lungs bilaterally. His ECG strip is shown below. Which of the following is the best next step in management of this patient?

Question

A 64-year-old man is admitted to the hospital with palpitations and lightheadedness for the past several days.  He has experienced palpitations previously, but recently they have seemed sustained and "uncomfortable."  The patient has had no chest pain or shortness of breath.  He has a history of coronary artery disease and prior percutaneous coronary interventions.  He is treated with metoprolol, lisinopril, aspirin, clopidogrel, and rosuvastatin.  Echocardiogram shows mild left ventricular dilation, a left ventricular ejection fraction of 30%, and no major valvular abnormality.  Serum potassium is 4.2 mEq/L and magnesium is 1.9 mg/dL.  On day 2 of hospitalization, the patient develops sudden-onset palpitations that feel like "fluttering in my chest."  Blood pressure is 122/60 mm Hg.  He is alert and does not appear to be in distress.  Examination shows clear lungs bilaterally.  His ECG strip is shown below.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d36d_ae2d_bc81_a328c4475ca2_MD0003_00 This patient's rhythm strip shows a regular wide-complex tachycardia with 2 fusion beats, which are essentially diagnostic for sustained monomorphic ventricular tachycardia (SMVT). Patients with coronary heart disease and left ventricular systolic dysfunction are at increased risk of ventricular arrhythmias, including VT and ventricular fibrillation (VF). rhythm strip Management of patients with SMVT depends on symptoms and hemodynamic status. Patients with SMVT who are clinically and hemodynamically stable can be initially managed with antiarrhythmic drugs. Intravenous amiodarone is usually the preferred agent, and other agents (eg, procainamide, sotalol, lidocaine) are reserved for patients who do not respond to amiodarone. Antiarrhythmics can convert the SMVT to sinus rhythm and avoid the need for urgent electrical cardioversion. (Choice B) Carotid sinus massage is a useful vagal maneuver to terminate paroxysmal supraventricular tachycardia (PSVT). PSVT is usually a regular, narrow-complex tachycardia; fusion beats are not seen. paroxysmal supraventricular tachycardia (PSVT) (Choice C) Digoxin is used for rate control in supraventricular arrhythmias (eg, atrial flutter, atrial fibrillation, atrial tachycardia), especially in patients with hypotension and/or heart failure who are unable to tolerate beta blockers or calcium channel blockers. However, it is not indicated for patients with SMVT and can potentially worsen ventricular arrhythmias. (Choice D) Patients with persistent tachyarrhythmia who are severely symptomatic (eg, altered mental status, acute heart failure or pulmonary edema, ischemic chest pain) or hemodynamically unstable (hypotension, signs of shock) should be managed with immediate synchronized electrical cardioversion. Patients with VF or pulseless VT should be managed with immediate defibrillation (unsynchronized shock). This patient is hemodynamically stable and does not need urgent synchronized cardioversion. (Choice E) Esmolol is an ultra-short-acting beta blocker used for rapid rate control in atrial flutter or fibrillation. It has no role in the management of SMVT. Educational objective: Stable patients with wide-complex tachycardia can be initially managed with antiarrhythmic drugs (eg, amiodarone, procainamide, sotalol, lidocaine). Synchronized electrical cardioversion is indicated for patients with persistent tachyarrhythmia who are severely symptomatic (altered mental status, acute heart failure or pulmonary edema, ischemic chest pain) or hemodynamically unstable (hypotension, signs of shock). References: Clinical management of ventricular tachycardia. (http://www.ncbi.nlm.nih.gov/pubmed/20887902) Part 7: Adult Advanced Cardiovascular Life Support: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. (http://www.ncbi.nlm.nih.gov/pubmed/26472995)

A 64-Year-Old Man Is Admitted to the Hospital with Palpitations