Abstract 11561: Cardiac Perivascular Fibrosis is Associated with Impaired Coronary Blood Flow in Patients with Non-ischemic Heart Failure
Background: Although myocardial interstitial fibrosis has been demonstrated to play an important role in the pathogenesis of chronic heart failure, the role of perivascular fibrosis, another form of fibrosis, remains to be clarified.
Methods: We examined 64 consecutive patients with non-ischemic heart failure (HF) in our hospital between January 2001 and April 2009. The underlying cause of HF included hypertrophic cardiomyopathy (HCM, n=16), hypertensive heart disease (HHD, n=11) and dilated cardiomyopathy (DCM, n=37) based on the findings by echocardiography, cardiac catheterization and endomyocardial biopsy (right ventricular side of the interventricular septum). We calculated the collagen volume fraction (CVF) and perivascular fibrosis ratio (PFR) in biopsy samples as follows; PFR = the area of perivascular fibrosis/the area of the vascular wall. We also examined Thrombolysis in Myocardial Infarction (TIMI) frame count in the left anterior descending coronary artery (LAD) to evaluate coronary blood flow.
Results: There was no significant correlation between CVF and PFR (P=0.84). Although CVF was comparable among HCM, HHD and DCM (1.11±1.04, 1.89±1.61, and 1.41±1.48, respectively), PFR was significantly higher in HCM than in DCM (1.78±1.09 vs. 1.23±0.44, P<0.05). PFR was not correlated with cardiac function parameters, such as left ventricular ejection fraction (LVEF), cardiac output, LV end-diastolic pressure, LV end-diastolic volume or pulmonary artery pressure. However, PFR was significantly correlated with TIMI frame count in LAD (P<0.0001, in all-cases combined), but not with that in the left circumflex or right coronary artery. This correlation remained significant in a logistic regression model tested with 7 variables (body mass index, PFR, CVF, hypertension, dyslipidemia, diabetes mellitus and atrial fibrillation).
Conclusions: These results indicate that cardiac perivascular fibrosis is associated with impaired coronary blood flow, but not with interstitial fibrosis or cardiac function, suggesting that it could be a new therapeutic target to improve coronary microcirculation in HF.
- © 2012 by American Heart Association, Inc.