Myocardial Expression of Fas and Recovery of Left Ventricular Function in Patients With Recent-Onset Cardiomyopathy Original Research Article

Objectives This study aimed to evaluate the role of gene expression for predicting myocardial recovery in recent-onset cardiomyopathy. Background Apoptosis may limit ventricular recovery. We examined the myocardial expression of Fas, Fas ligand (FasL), tumor necrosis factor (TNF)-alpha, and TNF receptor 1 (TNFR1), and myocardial recovery in patients from the multicenter Intervention in Myocarditis and Acute Cardiomyopathy (IMAC) study. Methods Endomyocardial biopsy samples were obtained in 20 patients with recent-onset (<6 months) idiopathic dilated cardiomyopathy (left ventricular ejection fraction [LVEF] ≤0.40). The LVEF was assessed at baseline and at 6 and 12 months by nuclear scans. Myocardial expression was assessed by ribonuclease (RNase) protection, normalized to a constitutively active gene (glyceraldehydes 3-phosphate dehydrogenase [GAPDH]) and reported as percent GAPDH expression. The change in LVEF at 6 and 12 months was compared by tertiles of expression. Results For all patients (14 men, 6 women; age 46.5 ± 10.7 years), the mean LVEF was 0.28 ± 0.05 at baseline and 0.40 ± 0.14 at six months. Patients in the highest tertile of Fas expression had minimal improvement at six months (ΔEF = 0.03 ± 0.05) when compared with the intermediate (ΔEF = 0.10 ± 0.13) and lowest tertiles (ΔEF = 0.21 ± 0.11, change in LVEF by tertile, p = 0.006). A similar relationship was seen with TNFR1 expression (highest tertile, ΔEF = 0.06 ± 0.07; lowest tertile, ΔEF = 0.21 ± 0.11, p = 0.02). In contrast with Fas and TNFR1, expression of TNF-alpha and FasL did not predict recovery of LV function. Conclusions In cardiomyopathy of recent onset, increased expression of Fas and TNFR1 was associated with minimal recovery of LV function. Apoptosis limits myocardial recovery, and represents a potential target for therapeutic intervention.