REDUCED REGIONAL MYOCARDIAL PERFUSION IN THE PRESENCE OF PHARMACOLOGIC VASODILATOR RESERVE
REDUCED REGIONAL MYOCARDIAL PERFUSION IN THE PRESENCE OF PHARMACOLOGIC VASODILATOR RESERVE
复制标题
DOI：
10.1161/01.cir.71.2.370
复制
发表时间：
1985-01-01
期刊：
影响因子：
37.8
通讯作者：
KLOCKE, FJ
中科院分区：
文献类型：
--
作者：
CANTY, JM;KLOCKE, FJ
为了确定在冠状动脉压力降低时局部心肌灌注的减少是否可靠地指示远端脉管系统的最大血管舒张，在开胸犬中以心率apprx研究了冠状动脉自动调节。60次/分钟，代谢需求、时间平均收缩压力和透壁血管舒张储备接近于通常静息条件下发现的水平。用可编程压力源控制旋压力。区域回旋支流入量为0.56 ± 0.56。0.04（SEM [平均值的标准误差]）ml. min-1. g-1时，旋动脉压等于自发压，下降到0.34 ± 0.34。0.02 ml. cntdot. min-1. g ~（-1），旋动脉压降至35 mm Hg。每一心肌层的减少相似，内皮细胞流量从0.68 ± 0.99下降到0.68 ± 0.99。0.04至0.39 . ±. 0.03 ml. cntdot. min-1. G-1.在35 mm Hg下腺苷诱导的血管舒张期间，全层和内皮细胞流量上升至0.92 ± 0.92。0.08和1.07 . ±. 0.10 ml. cntdot. min-1. G-1，分别。当冠状动脉压力降低到25毫米汞柱，自动调节功能再次发挥作用时，全层血流和内膜血流下降到0.28 ± 0.25毫米汞柱。0.03和0.28 ±。0.04 ml. cntdot. min-1. G-1.在25 mm Hg的腺苷血管舒张期间，心内膜流量没有显著增加，但心外膜储备仍然存在。在药理学血管扩张剂储备耗尽之前，局部心肌灌注cna显著减少。在没有心动过速的情况下，心内膜血管扩张储备可以持续到冠状动脉压力< 35 mm Hb，但通常在心外膜血管扩张储备之前耗尽。
To determine whether reductions in regional myocardial perfusion at reduced coronary arterial pressures reliably indicate maximal vasodilation of the distal vasculature, coronary autoregulation was studied in open-chest dogs at heart rates of .apprx. 60 beats/min, a level at which metabolic demand, time-average systolic compressive forces, and transmural vasodilator reserve approximate those found under usual resting conditions. Circumflex pressure was controlled with a programmable pressure source. Regional circumflex inflow was 0.56 .+-. 0.04 (SEM [standard error of the mean]) ml .cntdot. min-1 .cntdot. g-1 when circumflex pressure equaled spontaneous aortix pressure and fell to 0.34 .+-. 0.02 ml .cntdot. min-1 .cntdot. g-1 when circumflex pressure was reduced to 35 mm Hg. Reductions were similar in each myocardial layer, with endocardial flow falling from 0.68 .+-. 0.04 to 0.39 .+-. 0.03 ml .cntdot. min-1 .cntdot. g-1. During adenosine-induced vasodilation at 35 mm Hg, full-thickness and endocardial flows rose to 0.92 .+-. 0.08 and 1.07 .+-. 0.10 ml .cntdot. min-1 .cntdot. g-1, respectively. When coronary pressure was reduced to 25 mm Hg and autoregulation was again operative, full-thickness and endocardial flows fell to 0.28 .+-. 0.03 and 0.28 .+-. 0.04 ml .cntdot. min-1 .cntdot. g-1. During adenosine vasodilation at 25 mm Hg endocardial flow did not increase significantly but epicardial reserve remained present. Significant reductions in regional myocardial perfusion cna occur before pharamcologic vasodilator reserve is exhausted. In the absence of tachycardia, endocardial vasodilator reserve can persist to coronary pressures < 35 mm Hb, but is ordinarily exhausted before epicardial vasodilator reserve.