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In patients with ventricular tachycardias, various structural and functional conditions can be influenced by certain triggers, initiating the mechanism of the arrhythmia. Thorough understanding of these different factors is paramount for the appropriate choice of treatment. Several options are available for the management of ventricular tachycardias: antiarrhythmic drugs, ICD implantation and catheter ablation or a combination of the above. The prognosis of an individual patient is determined by the underlying disease, the mechanism of tachycardia and the selected therapy. The complexity of several conditions requires a specialized diagnostic approach and tailored medical management. Therefore the patients with the following diagnoses should be referred to a specialized electrophysiology center: survivors of sudden cardiac death old infarct scar, reduced ejection fraction and complex ectopy Cardiomyopathy with syncope or ventricular tachycardias Long QT-Syndrome Brugada Syndrome Right Ventricular Dysplasia recurrent syncopes of unclear etiology.

Indications for implantable cardioverter defibrillators (ICDs) are expanding. Defining long-term predictors of ICD therapies might help to identify those patients who will benefit most from implantation of an ICD. The objective of this study was to examine long-term predictors of appropriate ICD therapy among patients with coronary disease at high risk of sudden cardiac death. An analysis of 245 patients with coronary disease, who had been implanted with an ICD for primary or secondary prevention of sudden cardiac death, was performed. Time to appropriate ICD therapy, defined as antitachycardia pacing or shock, was evaluated by the Kaplan-Meier method. Cox regression analysis was performed to determine hazard ratios for factors predicting appropriate ICD therapies. During a mean (SD) follow-up of 41 (33) months, 115 patients (53%) experienced appropriate ICD therapy. Independent predictors of appropriate ICD therapy included advanced age, left ventricular ejection fraction (LVEF)35%, and impaired renal function, with covariate-adjusted hazard ratios of 1.36 per 10 years (95% CI, 1.11 - 1.66; P = 0.003), 1.78 (95% CI, 1.21 - 2.63; P = 0.004), and 1.59 (95% CI, 1.00 - 2.54; P = 0.050), respectively. Remote myocardial infarction (6 months prior to ICD implantation) was associated with higher probability of appropriate ICD therapy among patients with LVEF35% (adjusted HR 2.68 [95% CI, 1.05 - 6.86; P = 0.04]), but not among patients with LVEF35% (adjusted HR 1.09 [95% CI, 0.58 - 2.04; P = 0.79]). Left ventricular ejection fraction, advanced age, and renal impairment are long-term predictors of appropriate ICD therapy in patients with coronary disease at high risk of sudden cardiac death. Patients with an ejection fraction above 35% have few arrhythmic events early after the myocardial infarction but appropriate therapies become more frequent late after the myocardial infarction, possibly due to progression of the disease.