Influence of different aetiologies on clinical course and outcome in patients with dilated cardiomyopathy

Background The clinical phenotype dilated cardiomyopathy is assumed to be the endstage of a multifactorial aetiopathogenetic pathophysiology which includes a not satisfactorily defined group of patients with inflammatory cardiomyopathy. Methods Within the German Competence Network Heart Failure patients with heart failure due to dilated cardiomyopathy of viral/inflammatory ( DCM i/v) and nonviral/noninflammatory ( DCM ) aetiology were enrolled. After 1 year 237 patients (180 male/57 female) were re‐examined including complete clinical work‐up. The association of different clinical courses with the time from initial diagnosis of heart failure (newly: ≤ 1 year; late: > 1 year) was investigated. Results After 1‐year‐follow‐up New York Heart Association ( NYHA ) class (by −0·48 in newly diagnosed DCM and −0·82 in newly diagnosed DCM i/v in addition to −0·24 in late diagnosed DCM and −0·17 in late diagnosed DCM i/v) as well as left ventricular ejection fraction (+14% in newly diagnosed DCM and DCM i/v and +6% in later diagnosed DCM and DCM i/v) were significantly improved in all patients. In patients with early diagnosed dilated cardiomyopathy a strong improvement of NYHA class could be demonstrated. Conclusions This study demonstrates for the first time a significant interaction between duration of disease, NYHA class and left ventricular ejection fraction in patients with DCM . Our results clearly demonstrate that in patients with DCM an early diagnosis within 1 year after occurrence of clinical signs is associated with a strong improvement in the clinical course, whereas late diagnosis results in a loss of change in clinical course and outcome.