Predictors of long-term outcome in patients with biopsy proven inflammatory cardiomyopathy

BACKGROUND: The objective of this study was to identify prognostic indicators in patients with inflammatory cardiomyopathy (iCM) on endomyocardial biopsy (EMB). METHODS AND RESULTS: Between 2007 and 2011 all consecutive patients with diagnosed with iCM at EMB were retrospectively analyzed. The combined primary endpoint (EP) (1°EP) was cardiac death, aborted sudden cardiac death/appropriate implantable cardioverter defibrillator (ICD) shock, progressive heart failure requiring left ventricular assist device (LVAD) implantation and heart transplantation. 503 patients (mean age 58 ± 12 years, 73% male) were available for analysis. Genomes of cardiotrophic viruses were detected in 396 patients (79%) and immuno-histochemical signs of inflammation were present in 223 individuals (44%). After 3.6 ± 2.4 years of follow-up, cardiac mortality was 3.0% (n = 14) and a total of 8.6% (n = 40) reached the primary endpoint. Independent predictors for the 1°EP were: age ≥ 50 years, presence and duration (≤ 28 days) of symptomatic heart failure. A risk stratification approach based on the results of the multivariate analysis demonstrated that absence of signs and/or symptoms of congestive heart failure in younger (< 50 years) patients with longer (> 28 days) duration of disease appear to have an excellent prognosis with 100% survival and no events during follow-up. The presence of all above mentioned independent risk factors results in an 1°EP occurrence of 35.9%. CONCLUSIONS: Symptoms of heart failure, short duration of disease, and older age are indicators of poor outcome in patients with iCM.