Background: Contemporary therapeutic options have led to substantial improvement in survival of patients with heart failure. However, limited evidence is available specifically on idiopathic dilated cardiomyopathy. We thus examined changes in prognosis of a large idiopathic dilated cardiomyopathy cohort systematically followed during the past 30 years.
Methods and results: From 1977 to 2011, 603 consecutive patients (age, 53±12 years; 73% men; left ventricular ejection fraction, 32±10%) fulfilling World Health Organization criteria for idiopathic dilated cardiomyopathy, including negative coronary angiography, were followed up for 8.8±6.3 years. Patients were subdivided in 4 enrollment periods on the basis of heart failure treatment eras: (1) 1977-1984 (n=66); (2) 1985-1990 (n=102); (3) 1991-2000 (n=197); (4) 2001-2011 (n=238). Rates of patients receiving angiotensin-converting enzyme inhibitors/angiotensin receptors blockers, β-blockers, and devices at final evaluation increased from 56%, 12%, 8% (period 1) to 97%, 86%, 17% (period 4), respectively (P<0.05). There was a trend toward enrollment of older patients with less severe left ventricular dilatation and dysfunction during the years. During follow-up, 271 patients (45%) reached a combined end point including death (heart failure related, n=142; sudden death, n=71; and noncardiac, n=22) or cardiac transplant (n=36). A more recent enrollment period represented the most powerful independent predictor of favorable outcome {period 2 versus 1 (hazard ratio [HR], 0.64; P=0.04), period 3 versus 1 (HR, 0.35; P<0.001), period 4 versus 1 (HR, 0.14; P<001)}. Each period was associated with a 42% risk reduction versus the previous one (HR, 0.58; 95% confidence interval, 0.50-0.67; P<0.001), reflecting marked decreases in heart failure-related mortality and sudden death (period 4 versus 1: HR, 0.10; P<001 and HR, 0.13; P<0.0001, respectively).
Conclusions: Evidence-based treatment has led to dramatic improvement in the prognosis of idiopathic dilated cardiomyopathy during the past 3 decades. The benefits of controlled randomized trials can be replicated in the real world, emphasizing the importance of tailored follow-up and long-term continuity of care.
Keywords: cardiac resynchronization therapy; cardiomyopathy, dilated; drug therapy; heart failure; outcomes assessment.