Current Clinical Perspective Data-driven Decisions: The Importance of Clinical Trials in Arrhythmia Management

As a result of clinical trials, the management of arrhythmias has evolved over the past three decades. In the late 1960s, customary teaching was that ventricular premature depolarizations were dangerous and antiarrhythmic therapy, in hopes of reducing fatal consequences, became common place; however, following clinical trials such as CAST, IMPACT, and SWORD, we learned that, at least in postinfarct patients, arrhythmia suppression may lead to increased rather than reduced mortality. Such trials have led to a marked reduction in therapy of indiscriminate ventricular ectopy and have led to ongoing testing of specific subgroups identified as having par-ticularly high adverse prognostic risk. With the advent of cardiac monitoring and the confirma-tion that ventricular tachyarrhythmias are the most common cause for sudden death, their therapy, too, has evolved and matured, again aided by clinical trials. The ESVEM study prospec-tively examined the role of monitor-guided versus electrophysiologically guided drug therapy of ventricular tachyarrhythmias and confirmed that both approaches may have a role in reducing arrhythmic deaths—though the specific benefits of each technique remain somewhat unsettled. Both the ESVEM and CASCADE studies suggested that the most effective drugs for ventricu-lar tachyarrhythmias are the class II/III drugs, sotalol and amiodarone, both appearing mor