■房间隔缺损(ASDs)导致右心室容积负荷。ASD闭合并不总是缓解症状或提高运动能力,这可能是由左心室(LV)血流动力学受损解释的。这项研究使用来自心脏磁共振(CMR)成像和肱动脉血压的无创LV压力-容积(PV)环路评估了儿童ASD闭合的效果。与对照组相比。
■23名ASD儿童接受了CMR,其中17例在ASD关闭后7(6-9)个月进行了重新检查。包括12个对照。根据时间分辨的LV体积和肱动脉血压,从PV回路中得出血液动力学变量。ASD关闭后,左心室容量增加[76(70-86)与63(57-70)mL/m2,P=0.0001];它仍然小于对照组[76(70-86)vs.82(78-89)mL/m2,P=0.048]。与对照组相比,患有ASD的儿童有更高的收缩力[2.6(2.1-3.3)与1.7(1.5-2.2)mmHg/mL,P=0.0076]和动脉弹性[2.1(1.4-3.1)vs.1.4(1.2-2.0)mmHg/mL,P=0.034]。ASD关闭后,两者的收缩性[2.0(1.4-2.5)mmHg/mL,P=0.0001]和动脉弹性[1.4(1.3-2.0)mmHg/mL,P=0.0002]减少。
■尽管左心房分流导致低左心室充盈和右心室增大,LV仍然有效,没有证据表明儿童LV血流动力学受损.因此,在年轻时闭合ASD,同时心室是顺应性的,对于LV功能是有益的。LV体积,然而,ASD关闭后保持较小,这可能会影响长期心血管风险和运动表现。
UNASSIGNED: Atrial septal defects (ASDs) lead to volume-loaded right ventricles (RVs). ASD closure does not always alleviate symptoms or improve exercise capacity, which is possibly explained by impaired left ventricular (LV) haemodynamics. This study evaluated the effect of ASD closure in children using non-invasive LV pressure-volume (PV) loops derived from cardiac magnetic resonance (CMR) imaging and brachial blood pressure, compared with controls.
UNASSIGNED: Twenty-three children with ASD underwent CMR, and 17 of them were re-examined 7 (6-9) months after ASD closure. Twelve controls were included. Haemodynamic variables were derived from PV loops by time-resolved LV volumes and brachial blood pressure. After ASD closure, LV volume increased [76 (70-86) vs. 63 (57-70) mL/m2, P = 0.0001]; however, it was still smaller than in controls [76 (70-86) vs. 82 (78-89) mL/m2, P = 0.048]. Compared with controls, children with ASD had higher contractility [2.6 (2.1-3.3) vs. 1.7 (1.5-2.2) mmHg/mL, P = 0.0076] and arterial elastance [2.1 (1.4-3.1) vs. 1.4 (1.2-2.0) mmHg/mL, P = 0.034]. After ASD closure, both contractility [2.0 (1.4-2.5) mmHg/mL, P = 0.0001] and arterial elastance [1.4 (1.3-2.0) mmHg/mL, P = 0.0002] decreased.
UNASSIGNED: Despite the left-to-right atrial shunt that leads to low LV filling and RV enlargement, the LV remains efficient and there is no evidence of impaired LV haemodynamics in children. Closure of ASD at young age while the ventricle is compliant is thus beneficial for LV function. LV volumes, however, remain small after ASD closure, which may impact long-term cardiovascular risk and exercise performance.