Chamuleau Steven A J, Siebes Maria, Meuwissen Martijn, Koch Karel T, Spaan Jos A E, Piek Jan J
Department of Cardiology, Academic Medical Center, University of Amsterdam, B2-108, PO Box 22660, 1100 DD Amsterdam, The Netherlands.
Am J Physiol Heart Circ Physiol. 2003 Nov;285(5):H2194-200. doi: 10.1152/ajpheart.01021.2002. Epub 2003 Jun 26.
Homogeneity of microvascular resistance in different perfusion areas of the same heart is generally assumed. We investigated the effect of the severity of an epicardial stenosis on microvascular resistance in 27 patients with coronary artery disease and stable angina. All patients had an angiographically normal coronary artery, an artery with an intermediate lesion, and an artery with a severe lesion; the latter was treated with angioplasty. In each patient, distal blood flow velocity and pressure were measured during baseline and maximal hyperemia (induced by intracoronary adenosine) using a Doppler and pressure guide wire, respectively. The ratio of mean distal pressure to average peak blood flow velocity was used as an index for the microvascular resistance (MRv). Within patients, the hyperemic MRv was higher in arteries with more severe stenosis (P = 0.021). After percutaneous transluminal coronary angioplasty (PTCA), the hyperemic MRv decreased (pre-PTCA, 2.6 vs. post-PTCA, 1.9 mmHg.cm(-1)s(-1), P < 0.01) toward the value of the reference artery (1.7 mmHg.cm(-1)s(-1); P = 0.67). We conclude that there is a positive association between coronary lesion severity and variability of distal microvascular resistance that normalizes after angioplasty. This study challenges the concept of uniform distribution of hyperemic MRv that is relevant for the interpretation of both noninvasive and invasive diagnostic tests.
一般认为，同一心脏不同灌注区域的微血管阻力具有同质性。我们研究了27例冠心病稳定型心绞痛患者的心外膜狭窄严重程度对微血管阻力的影响。所有患者均有一条冠状动脉造影正常的动脉、一条有中度病变的动脉和一条有严重病变的动脉；后者接受了血管成形术治疗。在每位患者中，分别使用多普勒和压力导丝在基线和最大充血状态（由冠状动脉内注射腺苷诱导）下测量远端血流速度和压力。平均远端压力与平均峰值血流速度之比用作微血管阻力（MRv）的指标。在患者体内，狭窄更严重的动脉中充血状态下的MRv更高（P = 0.021）。经皮腔内冠状动脉成形术（PTCA）后，充血状态下的MRv降低（PTCA前为2.6，PTCA后为1.9 mmHg·cm⁻¹·s⁻¹，P < 0.01），接近参考动脉的值（1.7 mmHg·cm⁻¹·s⁻¹；P = 0.67）。我们得出结论，冠状动脉病变严重程度与远端微血管阻力变异性之间存在正相关，血管成形术后这种变异性恢复正常。本研究对充血状态下MRv均匀分布的概念提出了挑战，这一概念与无创和有创诊断测试的解读均相关。
