Cardiac function before and after surgery for pectus excavatum

Abstract

A 2006 meta-analysis concluded that thoracic surgery for pectus excavatum (PE) significantly improves cardiovascular function. However, that analysis was flawed by a high level of heterogeneity in the outcomes and inappropriate methods in 5 of the 8 publications analyzed. Therefore, a search of the published research from 1965 to the present was conducted, and only 5 publications were found that reported studies of cardiac function before and after operation, including 118 patients and 82 unoperated controls. Cardiac function was studied most frequently by echocardiography, despite the limitations imposed by the abnormal anatomy of pectus excavatum, but only studies that did not report cardiac or left ventricular dimensions or output were excluded. Studies using indirect estimates on the basis of oxygen pulse, which depends on several other variables, were not included. No improvements were found in left ventricular size, stroke volume, and cardiac output after surgery in 4 of 5 studies, using radionuclides, 2-dimensional echocardiography, radiographic planimetry, and cardiac output by the Fick method. Only a single study, with volumes calculated by squaring the diameter of the left ventricle from M-mode echocardiography, reported an increase (22%) in left ventricular stroke volume after operation, but that increased (17%) in the investigators' unoperated controls. This and 2 other studies used in this meta-analysis were also included in a meta-analysis conducted by Malek et al. In a fourth study, Malek et al included only the first study that found an improvement, but the final study reported no improvement. In conclusion, there is no reliable documentation of improved cardiac function from thoracic surgery for pectus excavatum.