PREOPERATIVE AND POSTOPERATIVE EXERCISE RESPONSE IN PULMONARY ATRESIA

Abstract

Patients (PTS) with pulmonary atresia (PA) subjectively may have increased exercise (EX) tolerance after 1st stage (RV to Pul. Art. conduit placement without VSD closure) or 2nd stage (RV to Pul. Art. conduit and VSD closure) repair. To measure precisely the degree of EX intolerance in PTS with PA and to assess improvement of EX tolerance after operation 10 PTS preop, 4 PTS after 1st stage and 7 PTS after 2nd stage repair performed graded cycle ergometry. The groups were similar in sex, age, ht. and BSA. As percent predicted, total work performed (P< 0.005), maximal power (P<0.01) and EX time (P<0.001) increased following either 1st or 2nd stage repair. EX performance was similar for PTS after 1st and 2nd stage repair. Resting and exercise blood pressures were similar among the three groups. As percent predicted, resting heart rate (HR) was lower (P<0.02) after 1st or 2nd stage repair than preop. Maximum EX HR was highest after 2nd stage repair (P<0.05). Both resting and EX oxygen saturation increased with degree of repair (P<0.05). Resting, respiratory rate, minute ventilation (Ve), oxygen uptake (VO2) and Ve/VO2 were similar among the groups. EX Ve and VO2 were greater (P<0.001 and Ve/VO2 less (P<0.001) for the two postop groups than the preop group.Graded cycle ergometry is a useful technique to evaluate the impact of surgery on congenital heart disease. By it we demonstrated that both 1st and 2nd stage repair of PA improves cardiorespiratory response to exercise and exercise tolerance.