No abstract

Index of microcirculatory resistance, a new index representing microvascular integrity, is a reliable early on-site determinant of myocardial viability and LV recovery after primary stenting for AMI.

Patients with early coronary artery disease and endothelial dysfunction had a higher lipid content in the vascular wall than patients with normal endothelial function. The result of the present study supports the hypothesis that endothelial dysfunction is associated with pathogenesis of early atherosclerosis.

Objective Endothelial dysfunction is an early manifestation of atherosclerosis. Inflammation and vasa vasorum play a pivotal role in the pathophysiology of plaque initiation, development and complications. Optical coherence tomography (OCT) allows high-resolution imaging of tissue microstructure. Therefore, the aim of this study was to test the hypothesis that segments with endothelial dysfunction show macrophages and/or vasa vasorum in patients with early coronary artery disease. Approach and Results OCT images were obtained from 40 patients with mild coronary atherosclerosis who underwent coronary endothelial function assessment. OCT findings including macrophages and micorchannels were evaluated in 76 coronary segments corresponding to those in endothelial response to acetylcholine. Coronary artery diameter (CAD) change in response to acetylcholine was more severe in segments showing macrophages (−17.7±14.7% vs. −6.3±13.9%, p<0.01) and microchannels (−15.9±15.9% vs. −6.4±13.5%, p<0.01) than those without. There were increasing trends of the prevalence of macrophages and microchannels with endothelial dysfunction as stratified by quartiles of CAD change (p<0.01 and p=0.02 for trend, respectively). In particular, segments with both macrophages and microchannels (n=12) tended to have worse endothelial function than those with macrophages alone (n=15) and microchannels alone (n=15) (−22.1±14.6% vs.−10.9±15.6% and −10.9±15.6%, p=0.07 and p=0.06, respectively). Conclusion Epicardial endothelial dysfunction was associated with OCT-identified macrophages and microchannels in mild coronary atherosclerosis. The current study further supports the role of inflammation and vasa vasorum proliferation in the early stage of coronary atherosclerosis.