Good prognosis for dilated cardiomyopathy without severe heart failure or arrhythmia.

In 124 patients with dilated cardiomyopathy, symptoms of heart failure and ventricular arrhythmia at initial assessment were related to outcome a mean of 43 months later. Using life table analysis, the two-year mortality from progressive heart failure was 59 per cent (90 per cent symptoms, six per cent (1-11 per cent) for patients with class 2 symptoms and zero for patients with class 1 symptoms. The two-year mortality from sudden death was 18 per cent (5-32 per cent) for patients with class 3 symptoms, eight per cent (3-14 per cent) for patients with class 2 symptoms and seven per cent (0-17 per cent) for patients with class 1 symptoms. Sudden death was more frequent in patients with ventricular tachycardia or frequent ventricular ectopics, irrespective of the severity of heart failure (15 per cent (7-23 per cent) vs. three per cent (0-8 per cent) at two years). These findings suggest that patients with dilated cardiomyopathy and mild symptoms often have a benign clinical course. However, occult ventricular arrhythmia is associated with an increased risk of sudden death.