Reybrouck T, Dumoulin M, Van der Hauwaert L G
Department of Pediatric Cardiology, Gasthuisberg University Hospital, University of Leuven, Belgium.
Am J Cardiol. 1988 Apr 1;61(10):861-5. doi: 10.1016/0002-9149(88)91080-6.
In 14 children who underwent a venous switch operation for complete transposition of the great arteries, exercise testing was performed 3 to 15 years (mean 8) after the operation. Exercise performance capacity was assessed by the determination of the ventilatory threshold during exercise and by the oxygen uptake (VO2) reached at a heart rate of 170 beats/min (VO2,170). The ventilatory threshold was defined as the highest oxygen uptake (VO2) at which the pulmonary ventilation (VE) stops to increase linearly when related to VO2. During exercise above this threshold a disproportionate increase in VE relative to VO2 is observed. The mean ventilatory threshold was significantly lower (p less than 0.01) than the normal mean value and averaged 72 +/- 15%, 67 +/- 15% and 70 +/- 13% of the predicted normal value for children of comparable age, weight and height, respectively. The mean value for VO2,170 also was significantly lower (p less than 0.05) than the normal mean value for children of comparable age, weight and height, and averaged 81 +/- 20%, 81 +/- 18% and 80 +/- 18%, respectively. Compared with normal control subjects of the same sex and age, the ventilatory threshold was surpassed sooner (p less than 0.001) and reached after 2 +/- 1 min instead of the 4 +/- 1 min required by the controls. In nearly half of the patients, a lower than normal (i.e. below the 95% confidence limit) heart rate response to exercise was observed. Theoretically, this could be interpreted as indicating a normal or high physical performance capacity.(ABSTRACT TRUNCATED AT 250 WORDS)
在14例接受大动脉完全转位静脉调转手术的儿童中，于术后3至15年（平均8年）进行了运动测试。通过测定运动期间的通气阈值以及心率为170次/分钟时达到的摄氧量（VO₂）来评估运动表现能力。通气阈值定义为与VO₂相关时肺通气（VE）停止线性增加的最高摄氧量（VO₂）。在高于此阈值的运动过程中，观察到VE相对于VO₂不成比例地增加。平均通气阈值显著低于正常平均值（p<0.01），分别相当于年龄、体重和身高相当的儿童预测正常值的72±15%、67±15%和70±13%。VO₂₁₇₀的平均值也显著低于年龄、体重和身高相当的儿童的正常平均值（p<0.05），分别平均为81±20%、81±18%和80±18%。与相同性别和年龄的正常对照受试者相比，通气阈值更快被超过（p<0.001），在2±1分钟后达到，而对照组需要4±1分钟。在近一半的患者中，观察到运动时心率反应低于正常（即低于95%置信限）。从理论上讲，这可以解释为表明身体运动表现能力正常或较高。（摘要截短于250字）
