Given acutely, terminate an existing arrhythmia. In the future they may be used to prevent arrhythmia recurrence. Although the mainstay of therapy for years, antiarrhythmic agents have only limited efficacy in preventing tachycardia. Therefore, sotalol has been shown to be effective for the treatment of both atrial and ventricular arrhythmias. The role of amiodarone will be discussed below.
Reentry is the most common mechanism responsible for clinical cardiac arrhythmias.
For a Re-entrant rhythm to sustain the leading edge of the wavefront of activation must encounter excitable tissue. This area between the leading edge of activation and the tail of refractoriness is known as the excitable gap. By introducing a single or train of premature impulses the tissue in the excitable gap can be pre-excited, rendering it refractory and terminating the tachycardia. In many patients with well tolerated VT ATP can terminate VT with minimal or no symptoms. These devices allow for therapy to be tailored to different arrhythmias in the same patient.