Pulmonary function in advanced pulmonary hypertension

Abstract

Pulmonary mechanical function and gas exchange were studied in 33 The availability of human heart-lung transplantation at our institution has led to the referral of a large number of patients with advanced pulmonary hypertension for consideration of surgery. So far 33 patients suffering from primary pulmonary hypertension or pulmonary hypertension secondary to congenital heart disease with Eisenmenger physiology have been studied in our pulmonary function laboratory (data from nine of them have been reported' but are included here and expanded to provide a more complete evaluation). Previous reports of similar patients have been limited to single case studies or small groups and have shown disparate results'-6; isolated reports of a restrictive ventilatory defect3 and patients with airflow obstruction2 have appeared.Given this background, a larger series such as this one, in which patients were comprehensively studied in the same laboratory with a uniform protocol, should provide a more accurate assessment of lung function in patients with pulmonary hypertension. MethodsThirty three patients suffering from advanced (stage IV, New York Heart Association) pulmonary vascular disease resulting from primary pulmonary hypertension (18 cases) and from congenital heart disease with Eisenmenger physiology (15 cases) were considered suitable for heart-lung transplantation after examination by at least two independent physicians who agreed that life expectancy in each case was probably less than 12 months. Cardiac catheterisation and pulmonary angiography were performed before referral in all cases. These were not repeated here in view of the associated morbidity and mortality. All clinical data, however, were reviewed in detail and patients with known causes of pulmonary hypertension other than congenital heart disease were excluded.Ages ranged from 17 to 45 with a mean of 32 years, and there were 17 men and 16 women. Almost half of the patients were smokers, with a mean smoking history of 18 pack years. No patient had a history of asthma, and blood eosinophil counts were consistently within normal limits.Pulmonary function was assessed by standard methods.' In brief, lung volumes, flow rates, 131