Theodor Baars1,2, Philipp Kahlert2, Albert Baars3, Heike Preibsch4, Tienush Rassaf2, Gerd Heusch1, Petra Kleinbongard1. 1. Institute for Pathophysiology, West German Heart and Vascular Centre Essen, University of Essen Medical School, Essen, Germany. 2. Institute for Clinic of Cardiology, West German Heart and Vascular Centre Essen, University of Essen Medical School, Essen, Germany. 3. Department of Biomimetics, Hochschule of Bremen, City University of Applied Science, Bremen, Germany. 4. Diagnostic and Interventional Radiology, University Hospital Tuebingen, Tuebingen, Germany.
Abstract
OBJECTIVE: Stent implantation into atherosclerotic coronary vessels induces the release of particulate debris and soluble vasoactive substances, which impair downstream microvascular function. Microvascular perfusion, however, is also determined by hemorheological parameters. We therefore analyzed now changes in erythrocyte (RBC) aggregation in coronary arterial blood during stent implantation. METHODS: Symptomatic male patients with stable angina pectoris and stenosis in their native right coronary artery (RCA) or saphenous vein graft on right coronary artery (SVG-RCA) were enrolled. Coronary arterial blood was taken before and coronary aspirate during stent implantation with a distal occlusion/aspiration device. RBC aggregation was determined using the erythrocyte adhesiveness/aggregation test. The ratio of clot-free area to whole area of a spread blood drop was quantified (rCFA). To evaluate the impact of soluble factors within aspirate plasma on RBC aggregation, separated RBCs of healthy volunteers were exposed to patients' coronary arterial blood and aspirate samples. RESULTS: rCFA was comparably increased in coronary aspirate of RCAs and SVG-RCAs after stent implantation (RCA: 25.7±2.1% vs 32.2±2.1%; SVG-RCA: 28.9±1.9% vs 33.3±2.0%, P<.01). The rCFA of healthy volunteers was increased after adding coronary aspirate plasma. CONCLUSIONS: Stent implantation into atherosclerotic coronary arteries induces an increase in RBC aggregation, potentially contributing to impaired microvascular perfusion.
OBJECTIVE: Stent implantation into atherosclerotic coronary vessels induces the release of particulate debris and soluble vasoactive substances, which impair downstream microvascular function. Microvascular perfusion, however, is also determined by hemorheological parameters. We therefore analyzed now changes in erythrocyte (RBC) aggregation in coronary arterial blood during stent implantation. METHODS: Symptomatic male patients with stable angina pectoris and stenosis in their native right coronary artery (RCA) or saphenous vein graft on right coronary artery (SVG-RCA) were enrolled. Coronary arterial blood was taken before and coronary aspirate during stent implantation with a distal occlusion/aspiration device. RBC aggregation was determined using the erythrocyte adhesiveness/aggregation test. The ratio of clot-free area to whole area of a spread blood drop was quantified (rCFA). To evaluate the impact of soluble factors within aspirate plasma on RBC aggregation, separated RBCs of healthy volunteers were exposed to patients' coronary arterial blood and aspirate samples. RESULTS: rCFA was comparably increased in coronary aspirate of RCAs and SVG-RCAs after stent implantation (RCA: 25.7±2.1% vs 32.2±2.1%; SVG-RCA: 28.9±1.9% vs 33.3±2.0%, P<.01). The rCFA of healthy volunteers was increased after adding coronary aspirate plasma. CONCLUSIONS: Stent implantation into atherosclerotic coronary arteries induces an increase in RBC aggregation, potentially contributing to impaired microvascular perfusion.