Tay Edgar L W, Gibson Derek, Inuzuka Ryo, Josen Manjit, Alonso-Gonzalez Rafael, Giannakoulas Georgios, Li Wei, Dimopoulos Konstantinos, Gatzoulis Michael A
Adult Congenital Heart Centre and Centre for Pulmonary Hypertension, Royal Brompton Hospital, London, United Kingdom.
Cardiol Young. 2012 Aug;22(4):381-9. doi: 10.1017/S1047951111001806. Epub 2011 Nov 9.
Systemic right ventricular systolic dysfunction is common late after atrial switch surgery for transposition of the great arteries. Total isovolumic time is the time that the ventricle is neither ejecting nor filling and is calculated without relying on geometric assumptions. We assessed resting total isovolumic time in this population and its relationship to exercise capacity.
A total of 40 adult patients with transposition of the great arteries after atrial switch - and 10 healthy controls - underwent transthoracic echocardiography and cardiopulmonary exercise testing from January, 2006 to January, 2009. Resting total isovolumic time was measured in seconds per minute: 60 minus total ejection time plus total filling time.
The mean age was 31.6 plus or minus 7.6 years, and 38.0% were men. There were 16 patients (40%) who had more than or equal to moderate systolic dysfunction of the right ventricle. Intra- and inter-observer agreement was good for total isovolumic time, which was significantly prolonged in patients compared with controls (12.0 plus or minus 3.9 seconds per minute versus 6.0 plus or minus 1.8 seconds per minute, p-value less than 0.001) and correlated significantly with peak oxygen consumption (r equals minus 0.63, p-value less than 0.001). The correlation strengthened (r equals minus 0.73, p-value less than 0.001) after excluding seven patients with exercise-induced cyanosis. No relationship was found between exercise capacity and right ventricular ejection fraction or long-axis amplitude.
Resting isovolumic time is prolonged after atrial switch for patients with transposition of the great arteries. It is highly reproducible and relates well to exercise capacity.
在大动脉转位心房调转手术后晚期，系统性右心室收缩功能障碍很常见。总等容时间是指心室既不射血也不充盈的时间，其计算不依赖于几何假设。我们评估了该人群静息状态下的总等容时间及其与运动能力的关系。
2006年1月至2009年1月，共有40例大动脉转位心房调转术后的成年患者以及10名健康对照者接受了经胸超声心动图检查和心肺运动试验。静息总等容时间以每分钟的秒数来测量：60减去总射血时间加上总充盈时间。
平均年龄为31.6±7.6岁，男性占38.0%。有16例患者（40%）存在右心室中度或以上收缩功能障碍。观察者间和观察者内对总等容时间的一致性良好，患者的总等容时间显著长于对照组（每分钟12.0±3.9秒对6.0±1.8秒，p值小于0.001），且与峰值耗氧量显著相关（r=-0.63，p值小于0.001）。排除7例运动诱发青紫的患者后，相关性增强（r=-0.73，p值小于0.001）。未发现运动能力与右心室射血分数或长轴振幅之间存在关联。
大动脉转位患者心房调转术后静息等容时间延长。它具有高度可重复性，且与运动能力密切相关。
