Nir A, Driscoll D J, Mottram C D, Offord K P, Puga F J, Schaff H V, Danielson G K
Section of Pediatric Cardiology, Mayo Clinic, Rochester, Minnesota 55905.
J Am Coll Cardiol. 1993 Jul;22(1):216-20. doi: 10.1016/0735-1097(93)90837-q.
The purpose of this study was to assess whether there is deterioration of aerobic capacity over time after the Fontan operation in individual patients.
We previously observed that maximal aerobic capacity after the Fontan operation was lower in older patients than in younger patients. It was unclear whether this represented a decrease in aerobic capacity with time after operation or was a function of studying patients of different ages at different times postoperatively.
All patients who had more than one postoperative exercise study were included. There were 25 patients (19 male, 6 female), aged 3.8 to 39 years at the time of the operation. The first exercise test was performed, on average, 2.2 years after the Fontan operation, and the last exercise test was performed, on average, 5.9 years (range 1.8 to 13) after the operation. In 11 patients, coronary sinus drainage was left on the pulmonary venous side. Five patients had had a previous Glenn operation. Exercise was performed to exhaustion with use of a 3-min incremental cycle protocol.
Exercise duration, oxygen uptake, blood pressure, respiratory rate, minute ventilation, pulmonary blood flow index, exercise factor, ST-T wave changes and the prevalence of arrhythmias were similar during the first and last tests. Exercise systemic arterial blood oxygen saturation decreased from the first to the last postoperative test (p < 0.006) regardless of age. The percent of predicted heart rate, at rest and during maximal exercise, decreased more in older patients from the first to the last test (p < 0.05 for rest and exercise).
In this select group of patients, exercise tolerance remained relatively unchanged over the range of 13 years after the Fontan operation. Heart rate at rest and during maximal exercise decreased more than predicted for age in older patients. A small but significant progressive decrease in systemic arterial blood oxygen saturation was found. The former might represent abnormal sinus node function in patients with functional single ventricle, and the latter might represent a tendency toward development of abnormal ventilation/perfusion patterns resulting from the development of small pulmonary arteriovenous fistulas or an effect of position of the coronary sinus postoperatively.
本研究旨在评估在接受Fontan手术的个体患者中，有氧能力是否会随时间推移而下降。
我们之前观察到，Fontan手术后老年患者的最大有氧能力低于年轻患者。目前尚不清楚这是代表术后随着时间推移有氧能力的下降，还是由于在术后不同时间研究不同年龄患者所导致的结果。
纳入所有接受过不止一次术后运动研究的患者。共有25例患者（19例男性，6例女性），手术时年龄为3.8至39岁。首次运动测试平均在Fontan手术后2.2年进行，末次运动测试平均在手术后5.9年（范围1.8至13年）进行。11例患者的冠状静脉窦引流留在肺静脉侧。5例患者曾接受过Glenn手术。采用三分钟递增式自行车运动方案进行运动直至力竭。
首次和末次测试期间，运动持续时间、摄氧量、血压、呼吸频率、分钟通气量、肺血流量指数、运动因子、ST - T波变化以及心律失常的发生率相似。无论年龄大小，术后首次至末次测试期间，运动时全身动脉血氧饱和度均下降（p < 0.006）。从首次到末次测试，老年患者静息和最大运动时预测心率的百分比下降幅度更大（静息和运动时p < 0.05）。
在这组特定患者中，Fontan手术后13年期间运动耐量相对保持不变。老年患者静息和最大运动时的心率下降幅度超过年龄预测值。全身动脉血氧饱和度出现了小幅度但显著的逐渐下降。前者可能代表功能性单心室患者的异常窦房结功能，后者可能代表由于小的肺动静脉瘘形成或术后冠状静脉窦位置的影响导致异常通气/灌注模式发展的趋势。
