Repeat Catheterization in Ventricular Septal Defect and Pulmonary Hypertension

Abstract

Although it has been shown that children with a large ventricular septal defect frequently develop heart failure during infancy (Marquis, 1950;Morgan, Griffiths, and Blumenthal, 1960) it is our experience that if they can be tided over this period they often improve spontaneously and remain well for many years.The tendency to maintain this improvement is unexpected: deterioration appears more likely owing to progressive pulmonary vascular disease resulting from prolonged exposure of the pulmonary arterial system to systemic pressures. Hmmodynamic data are scanty and mainly derived from single catheter studies: the classic paper is that of Brotmacher and Campbell (1958) who concluded that the pulmonary vascular resistance tended to rise with advancing years, a contention supported by Goodwin (1960). Few serial catheterization studies have been reported, particularly in patients with pulmonary hypertension (Kay, Zimmerman, and Cross, 1955;Adams et al., 1959;Fyler et al., 1958; Downing, 1959) but recently Lynfield et al. (1961) gave data from serial studies on a large number of patients, several of whom did have severe pulmonary hypertension. In these hypertensive patients they found no tendency to progressive elevation of the pulmonary vascular resistance.This aspect of the natural history is of theoretical and practical importance. We therefore re-catheterized 10 children who, on initial investigation three to seven years previously, were found to have a large ventricular septal defect, a left-to-right shunt, and systemic pressures in the right ventricle. In this paper we report our results. SUBJECTS AND METHODSThe 10 patients, 4 girls and 6 boys, first attended the Department of Cardiology, Manchester Royal Infirmary, at ages ranging from 2 years 11 months to 15 years. All were subjected to routine clinical, radiological, and electrocardiographic examination and underwent cardiac catheterization. They all had a large ventricular septal defect, a left-to-right shunt, and systemic pressures in the right ventricle. In 8, the pulmonary resistance was elevated (over 200 c.g.s. units) and the pulmonary systolic pressure was over 65 mm. Hg; they, therefore, corresponded to Group 4 of Brotmacher and Campbell and Group III of Lynfield et al. The other 2 children had infundibular pulmonary stenosis at the time of the first catheterization. After intervals of between three and seven years they were completely re-examined and re-catheterized. The height and weight on each occasion were plotted on Wetzel's guide for evaluating physical fitness in terms of physique; the physique channels range through A4 (obese); A3, A2 (stocky); A, M, Bl (good); B2 (fair); B3 (borderline); B4 (poor).Cardiac catheterization was carried out in the usual manner, premedication being with heroin or a mixture of chlorpromazine, pethidine, and phenergan in the younger, and seconal in the older children.In all patients below the age of 12 years, oxygen consumption was calculated by the method used by Lynfield et al. (1961) based on the basal meta...