Cardiac Arrhythmia Suppression Trial CAST

The Cardiac Arrhythmia Suppression Trial (CAST) Investigators, W. Engl J. Med. 321, 406 (1989). 

Mortality In the National Heart, Lung, and Blood Institute s Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multicentered, randomized, double-blind study in patients with asymptomatic nonlife-threatening ventricular arrhythmias who had an Ml more than 6 days but less than 2 years previously, an excessive mortality or nonfatal cardiac arrest rate was seen in patients treated with encainide or flecainide (7.7%) compared with that seen in patients assigned to matched placebo-treated groups (3%). The averaged duration of treatment with encainide or flecainide in this study was 10 months. 

CAST (1989) Preliminary report effect of encainide and flecainide on mortality in a randomized trial of arrhythmia suppression after myocardial infarction. The cardiac arrhythmia suppression trial (CAST) investigators. The New En and Journal of Medicine, 321, 406 12. 

Question the need for therapy. The mere identification of an abnormality of cardiac rhythm does not necessarily require that the arrhythmia be treated. An excellent justification for conservative treatment was provided by the Cardiac Arrhythmia Suppression Trial (CAST) referred to earlier. 

Premature ventricular contractions (PVCs) are commonly recorded in patients convalescing from myocardial infarction. Since such arrhythmias have been associated with an increased risk of sudden cardiac death, it had been the empiric practice of many physicians to treat PVCs, even if asymp-tomatic, in such patients. In CAST (Cardiac Arrhythmia Suppression Trial [CAST], Echt et al, 1991), an attempt was made to document the efficacy of such therapy in a controlled clinical trial. The effects of several antiarrhythmic drugs on arrhythmia frequency were first evaluated in an open-label fashion. Then, patients in whom antiarrhythmic therapy suppressed PVCs were randomly assigned, in a double-blind fashion, to continue that therapy or its corresponding placebo. 

Proarrhythmic effects of antiarrhythmic drugs In the Cardiac Arrhythmia Suppression Trial (CAST) treatment with encainide and flecainide, two class IC antiarrhythmic agents, successfully prevented ventricular ectopic beats in patients who had myocardial infarction. However, continued therapy with either drug was associated with a two- to three-fold increase in death due to cardiac arrhythmias. Similar results were reported for moricizine. Increased death was probably due to drug-induced fatal arrhythmias triggered by recurrent myocardial ischemia. 

Asymptomatic Carotid Atherosclerosis Study Group (1995). Carotid endarterectomy for patients with asymptomatic internal carotid artery stenosis. Journal of the American Medical Association 273 1421-1428 Barnett HJ, Taylor DW, Ehasziw M etal. (1998). The final results of the NASCET trial. New England Journal of Medicine 339 1415-1425 Cardiac Arrhythmia Suppression Trial (CAST) Investigators (1989). Preliminary report effect of encainide and flecainide on mortality in a randomised trial of arrhythmia suppression after myocardial infarction. New England Journal of Medicine 321 406-412 Charleson ME, Horwitz RI (1984). Applying results of randomised trials to clinical practice impact of losses before randomisation. British Medical Journal 289 1281-1284... 

In the wake of the preliminary and final reports of the Cardiac Arrhythmia Suppression Trial (CAST) (7,8), which showed that there was an increased risk of death among patients who took encainide and flecainide after myocardial infarction, there have been many pubheations in which the implications of these findings have been thoroughly discussed (9-13). The relative risk of death or cardiac arrest due to dysrhjdhmias in the treated patients was 2.6 and the relative risk due to all causes... 

Bigger JT Jr. The events surrounding the removal of encainide and flecainide from the Cardiac Arrhythmia Suppression Trial (CAST) and why CAST is continuing with moricizine. J Am Coll Cardiol 1990 15(l) 243-5. 

The Cardiac Arrhythmia Suppression Trial (CAST) highlighted the importance and awareness of proarrhythmia. The main finding of CAST was that, despite elimination of complex ventricular ectopy after myocardial infarction, mortality was significantly higher in patients treated with encainide or flecainide. Others have reported that the overall risk of cardiac mortality is higher, presumably due to proarrhythmia, in patients treated with Type la antiarrhythmics for atrial fibrillation who have con-... 

Prophylactic antiarrhythmic drug use does not improve total survival. The Cardiac Arrhythmia Suppression Trial (CAST) (125), based on the supposition that frequent PVCs after myocardial infarction are associated with increased risk of sudden death, evaluated the long-term benefits of antiarrhythmic drug therapy for those patients with > lOPVCs/h after myocardial infarction. After PVC suppression was shown to occur on the antiarrhythmic drug, patients were randomized to the antiarrhythmic drug showing apparent benefit (Class... 

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