Normalized cardiopulmonary exercise function in patients with pectus excavatum three years after operation

Abstract

Background: During exercise cardiac function is often limited in patients with pectus excavatum. Therefore, we hypothesized that cardiopulmonary exercise function would improve after the Nuss procedure.

Methods: Seventy-five teenagers (49 patients, 26 controls) were investigated at rest and during bicycle exercise before surgery, and 1 year and 3 years postoperatively (after pectus-bar removal). Echocardiography and lung spirometry were performed at rest. Cardiac output, heart rate, and aerobic exercise capacity were measured using a photoacoustic gas-rebreathing technique during rest and exercise.

Results: Forty-four patients and 26 controls completed 3 years follow-up. Preoperatively, patients had lower maximum cardiac index, mean ± SD, 6.6 ± 1.2 l·min(-1)·m(-2) compared with controls 8.1 ± 1.0 l·min(-1)·m(-2) during exercise (p = 0.0001). One year and 3 years postoperatively, patients' maximum cardiac index had increased significantly and after 3 years there was no difference between patients and controls (8.1 ± 1.2 l·min(-1)·m(-2) and 8.3 ± 1.6 l·min(-1)·m(-2), respectively [p = 0.572]). The maximum oxygen consumption was unchanged. Left ventricular dimensions increased in patients over 3 years; however, no difference was seen between the 2 groups. Preoperatively, patients had lower forced expiratory volume in the first second of expiration (FEV1; 86% ± 13%) as compared with controls (94% ± 10%), p = 0.009. Postoperatively, no difference was found in FEV1 between the 2 groups.

Conclusions: Before operation, FEV1 and maximum cardiac index were lower in patients compared with healthy, age-matched controls. One year after, both parameters had increased, although only FEV1 had normalized. After 3 years and bar removal, cardiopulmonary function in patients during exercise had normalized.