[Diagnosis of ischemia and revascularization in patients with ventricular tachyarrhythmia].

Sustained ventricular tachyarrhythmia usually occurs on the basis of structural heart disease, particularly coronary heart disease (CAD). Although monomorphic ventricular tachycardia (VT) appears mainly in patients with CAD, it is typically not triggered by acute ischemia, in contrast to polymorphic VT or ventricular fibrillation (VF). To judge if VT is caused by acute ischemia is even more difficult in context with an elevated highly sensitive troponin T which is generally elevated in sustained VT because tachycardia in chronic stable coronary artery sclerosis causes a mismatch between increased oxygen demand and limited oxygen supply. Therefore, acute coronary angiography and revascularization may frequently not be necessary in monomorphic VT, will usually not improve rhythm stabilization, and may lead to misinterpretation of monomorphic VT being caused by a coronary stenosis. This can lead to withholding antiarrhythmic therapy after revascularization since it is assumed that the cause of VT has been treated. On the other hand, acute coronary angiography and revascularization are useful in polymorphic VT/VF, ECG signs of ischemia, or typical chest pain before occurrence of VT/VF. Coronary angiography should also be performed in patients with VT with newly diagnosed reduced left ventricular function and before catheter ablation.