Abstract 16457: Analysis of Endomyocardial Biopsies in Cardiomyopathies- Proof of Diagnostic Value in Left versus Right Ventricular Biopsy
Background: Endomyocardial biopsies (EMBs) are still the gold standard for establishing the diagnosis of inflammatory cardiomyopathy (CMi), and to rule out any other specific heart muscle diseases. The aim was to prove prospectively the diagnostic value of RV versus left ventricular (LV) EMB specimens to base a recommendation for clinical practice in patients with cardiomyopathies.
Methods and Results: The present study subjects consisted of n=68 prospectively evaluated patients (50 males, 18 females). Coronary angiography was performed in each patient before biventricular EMB procedure. Taken up to 9 biopsies from each ventricle, there was no statistically difference in presence of cardiac inflammation both LV- and RV EMB: LFA-1+ lymphocytes LV v.s RV EMB, P=0.2; CD3+ T-lymphocytes P=0.6; CD45R0 T-memory cells, P=0.4; and cell adhesion molecules HLA-1, P=0.1; ICAM-1, P=0.8; VCAM-1, P=0.8. Beyond, virus genomes of parvovirus B19 was detected in both LV-EMB und RV-EMB equally (P=0.6).
Pronounced increased fibrosis was obtained in LV EMBs of 18 (26.4%) patients in contrast to only 3 (4.4%) patients with RV-EMB. This was associated with a 2.2 fold increased mRNA abundance of α-smooth muscle actin (α-SMA) in LV compared to RV, as a manifestation for transdifferentiation from fibroblasts into myofibroblasts (activated fibroblasts), leading to increased ventricular stiffness and adverse remodeling.
Regarding to the cardiomyocytes diameter in 30.4% of LV-EMB a hypertrophy (diameter ≥26mm) was discovered in contrast to only 5.7% in RV-EMB.
Conclusion: Intramyocardial inflammation and virus genomes can be detected in RV und LV equally, but with regard to histopathological features especially fibrosis and hypertrophy a LV-EMB is usefull- particularly to estimate the prognosis of the disease.
- © 2013 by American Heart Association, Inc.