Maximal supine exercise haemodynamics after open heart surgery for Fallot's tetralogy.

Abstract

SUMMARY Maximal supine exercise studies at the time of heart catheterisation were performed one to five years after open heart surgery for Fallot's tetralogy on 29 subjects 6 to 16 years of age. During exercise right ventricular systolic pressure exceeded 50 nmmHg in all but 2 subjects, and end-diastolic pressure increased to over 15 mmHg in 10 subjects. Pulmonary artery peak systolic pressure was abnormal in 5 patients. Maximal exercise cardiac index was below the normal range in only 2 subjects, but below the mean for normals in 80 per cent of the patients. Only 3 patients had clinical exercise performances below the 3rd centile of normal subjects using a maximal upright bicycle exercise test, and only 1 subject was below the normal range for endurance time on the Bruce treadmill test. The patients in this series performed better than those in other series, possibly because of their younger age at operation, the use of a large control series of normal subjects taken from a clinic population, the willingness of the patients to work to near exhaustion, and previous encouragement of the patients to become normally active children.

Exercise Studies in Tetralogy of Fallot: A Review

“…Some of the best outcomes were reported in the German study of Mocellin et al [53] and the Canadian study by Cumming [12] in patients with excellent surgical results. As was pointed out by Cumming [12], these findings probably resulted in part from a greater maximal effort during the exercise but also from a better physical fitness of the Canadian children due to a greater level of physical activity in general compared to U.S. children. The importance of physical activity is also supported by subsequent training studies after ICR, which all showed improved physical performance after training [5,7,25,74], and by observations that patients who participate in varsity sports after ICR perform better than nonathletes [36,93].…”

“…However, if patients are corrected in childhood, work capacity appears to be more related to a good surgical outcome than age at ICR per se [93]. Some of the best outcomes were reported in the German study of Mocellin et al [53] and the Canadian study by Cumming [12] in patients with excellent surgical results. As was pointed out by Cumming [12], these findings probably resulted in part from a greater maximal effort during the exercise but also from a better physical fitness of the Canadian children due to a greater level of physical activity in general compared to U.S. children.…”

“…Ventricular tachycardia (VT) was reported in 11 studies, with an incidence of 9. [12]. In contrast to ventricular arrhythmias, supraventricular arrhythmias have been less common in tetralogy of Fallot.…”

Time course of oxygen uptake and heart rate during Bruce treadmill test in patients following surgery for tetralogy of Fallot

“…However, Rocchini et al [15] have reported that low exercise capacity is noted in postoperative TF patients regardless of the presence or absence of pulmonary regurgitation. Hemodynamic factors, such as a diminished cardiac output [4,7,12], elevated right ventricular systolic [3,4,9] and enddiastolic [3,4,9,10] pressures, a decrease maximal heart rate [4-6, 11, 12, 14, 16-18], and abnormal distribution of lung perfusion [19] have also all been [6,7,16] have also reported that improved exercise performance has been associated with earlier primary repair. The relationship between the age at operation and functional capacity has been weil described by Wessel et al [5].…”

“…However, some patients are noted to have diminished exercise tolerance [3], maximal oxygen uptake [4][5][6][7], and maximal heart rate [5,6,8] during exercise. Persistent high right ventricular systolic [3,9] and end-diastolic pressures [3,4,9,10], as well as reduced stroke volume [11] and cardiac output, may help to explain these findings. The residual symptoms are more apparent during exercise than at rest.…”