Abstract 4206: Microvascular Dysfunction and Left Ventricular Chamber Stiffness after Successful Percutaneous Coronary Intervention Critically Determine Left Ventricular Remodeling in Patients with Acute Myocardial Infarction
In patients with acute myocardial infarction (AMI), the short deceleration time of left ventricular (LV) early filling by Doppler is a powerful independent predictor of LV remodeling. On the other hand, recent studies have shown that microvascular dysfunction in recanalized infarct-related coronary arteries may predict progressive LV dilation. The purpose of this study was to examine the effects of both microvascular dysfunction and LV chamber stiffness on LV remodeling after successful percutaneous coronary intervention (PCI) in AMI patients. Two hundred and one consecutive patients with first anterior AMI were studied following successful PCI. Microvascular injury was evaluated on the basis of coronary flow velocity patterns immediately after successful PCI using Doppler guidewires. We defined the presence of microvascular dysfunction as diastolic deceleration time ≤600 ms and the presence of systolic flow reversal. LV filling patterns were determined by mitral inflow pulsed-wave Doppler examination on day 3 after AMI. Deceleration time ≤130 ms was defined as restrictive. We classified the patients into three categories: without restrictive and microvascular dysfunction (group 1, n=116), with restrictive or microvascular dysfunction (group 2, n= 38), and with restrictive and microvascular dysfunction (group 3, n=47). Left ventriculograms were obtained immediately and 6 months after PCI. LV remodeling was defined as an increase in end-diastolic volume index ≥20%. Group 3 was at the highest risk of LV remodeling, while group 1 was at the lowest (Table⇓). Assessment of both microvascular dysfunction and LV chamber stiffness enable accurate prediction of LV remodeling in AMI patients after successful PCI.