Management of Supraventricular and Ventricular Tachycardia

Diagnosis and Initial Management

The American College of Cardiology recommends immediate synchronized cardioversion as the definitive treatment for hemodynamically unstable SVT when vagal maneuvers and adenosine fail or are not feasible 1, 2
Look for signs of instability, including hypotension, altered mental status, shock, chest pain, or acute heart failure, in patients with SVT 3
Synchronized cardioversion is highly effective at terminating SVT and must be performed promptly to restore sinus rhythm 1, 2

The American College of Cardiology suggests beginning with vagal maneuvers, followed immediately by adenosine if unsuccessful, for hemodynamically stable SVT 1, 4, 3
Perform Valsalva maneuver with patient supine, bearing down against closed glottis for 10-30 seconds at 30-40 mmHg pressure 1, 2
Modified Valsalva technique achieves approximately 43% success rate 4
Adenosine terminates AVNRT in approximately 95% of patients and serves both therapeutic and diagnostic purposes 1, 5, 4

IV diltiazem or verapamil are particularly effective with 80-98% conversion rates for hemodynamically stable SVT 1, 2, 3
IV beta-blockers are reasonable alternatives with excellent safety profile, though diltiazem is more effective than esmolol 1, 5
Never give calcium channel blockers or beta-blockers if VT or pre-excited atrial fibrillation is suspected, as this can precipitate ventricular fibrillation 1, 2, 5

Oral verapamil or diltiazem can be used for ongoing management in patients not pursuing catheter ablation 5, 4
Catheter ablation is the most effective long-term therapy with 94.3-98.5% success rates 3
The American College of Cardiology emphasizes the importance of accurate rhythm diagnosis before treatment, as the management algorithms for SVT and VTach differ fundamentally 1, 2