Coronary Dysfunction in Developing Myocardial Damage in Congenital Heart Diseases

据报道，在成年期，肥厚心脏的心肌缺血是进行性心肌损害的恶化因素。然而，有关心肌负荷明显超负荷的先天性心脏病患者冠脉血流动力学的研究较少。为了评价先天性心脏病患者的冠状动脉血流动力学，我们用冠状动脉内多普勒导丝检测了静息状态和三磷酸腺苷(ATP)诱导的充血反应过程中的冠状动脉血流动力学。本研究组包括28例日本患者(男18例，女10例)，平均年龄5.12±4.9岁，接受常规心导管检查，以评价术前(16例，TOF 10例，DORV 4例，TGA 2例)和术后(12例；TOF 9例，DORV 3例)CHD。正如我们之前报道的，冠状动脉血流速度变量是使用长175厘米，0.018英寸的可弯曲的可操纵的血管成形…来测量的。更多TiC导丝，其尖端集成了12-MHz压电超声换能器(FloWireR，Cardio Metrics，Inc.，Mountain View，California)。通过计算冠脉内注射三磷酸腺苷后的充血平均峰值速度(APV)和基础APV的商来评估冠脉血流储备(CFR)，CFR是反映微血管床内充血能力的指标。将以前报道的年龄匹配的对照数据作为比较冠状动脉血流模式的参考值。在术前组，16例LAD患者中69%的患者DSVR值显著高于RCA患者，81%的患者在RCA患者中DSVR值显著升高。在16例LAD患者中，11例(75%)在收缩期检出明显的反向血流信号，在右冠状动脉(RCA)中检测到13例(81%)。另一方面，在术后组中，仅有1例(8%)LAD患者的DSVR值显著升高，而在RCA患者中无一例出现DSVR升高。左前降支仅1例(8%)出现反向血流信号，右冠状动脉仅2例(17%)。在术前组中，LAD组16例患者中有9例(56%)CFR值显著降低，RCA组所有患者CFR值均显著降低(100%)。另一方面，在术后组中，LAD和RCA的12例患者中只有3例(25%)的CFR显著降低。每支血管CFR降低的患者术后时间较短(1t；2年)，CFR正常的患者术后时间较长。在本研究中，所有术前患者的冠状动脉血流频谱异常和CFR降低表明冠状动脉阻力显著增加，小冠状动脉的扩张力降低或收缩相心肌顺应性下降，发展为心肌缺血或不可逆转的心肌损害。在先天性心脏病合并严重心肌负荷过高的处理和外科手术中，应慎重考虑继发性冠状动脉功能不全，以预防心肌缺血作为不可逆心肌损害的加重因素。较少

It has been reported, in adulthood, that myocardial ischemia in the hypertrophic heart was an exacerbation factor to progressive myocardial damage. However, there have been few studies on the coronary hemodynamics in the congenital heart diseases with significant myocardial overload. To assess the coronary hemodynamics in the congenital heart diseases, we examined the coronary flow-velocity dynamics using an intracoronary Doppler guide wire at rest and during the adenosine triphosphate (ATP) -induced hyperemic responses in patients with cyanotic congenital heart diseasesThis study group consisted of 28 Japanese patients (18 males and 10 females) (mean ages : 5.12 ± 4.9 years) who were undergoing the routine cardiac catheterization for the evaluation of pre- (16 patients ; 10 TOF, 4 DORV, 2 TGA) and post-operative (12 patients ; 9 TOF and 3 DORV) CHDs. As we previously reported, coronary flow-velocity variables were measured using a 175-cm-long, 0.018-inch flexible, steer able angioplas … More tic guide wire with a 12-mHz piezoelectric ultrasound transducer integrated into its tip (FloWireR, Cardio metrics, Inc., Mountain View, California). The coronary flow reserve (CFR), which was an indicator of the potency in the micro vascular bed, was assessed by calculating the quotient of the peak hyperemic average peak velocity (APV) after intracoronary injection of ATP and the baseline APV. Age-matched control data reported previously were used as reference values for comparisons of coronary flow patternsIn the pre-operative group, significantly higher DSVR values were noted in 69 % of 16 patients in the LAD and in 81 % in the RCA. A significant reversed flow signal in the systolic phase were also detected in 11(75 %) of 16 patients in the LAD, and 13(81 %) in the RCA. On the other hand, in the post-operative group, significantly higher DSVR values were detected in only 1(8 %) of 12 patients in the LAD, and none in the RCA. A reversed flow signal was noted in only 1(8 %) in the LAD and 2(17 %) in the RCA. In the pre-operative group, significantly lower CFR values were noted in 9(56 %) of 16 patients in the LAD, and in all patients (100 %) in the RCA. In the Posto-perative group, on the other hand, a significant reduction in CFR was noted in only 3(25 %) of 12 patients in both of the LAD and the RCA. The post-operative periods were shorter (< 2 years) in the patients with a reduced CFR in each vessel, and longer in the Patients with a normal CFR. AIn this study, abnormal coronary flow profile and reduced CFR noted in all of the pre-operative patients indicate a significant increase in coronary resistance with a reduced dilatory potency of the small coronary artery or a decrease in myocardial compliance in the systolic Phase, developinging in myocardial ischemia or irreversible myocardial damage. In management and surgical operation of the congenital heart diseases with significant myocardial overload, it is necessary to take into careful consideration the secondary coronary dysfunction for preventing myocardial ischemia as an exacerbation factor to irreversible myocardial damage. Less