Right heart catheterization in the pre-operative evaluation of patients with lung cancer

The right heart catheterization and lung function data of 637 consecutive patients with lung cancer evaluated preoperatively were analysed retrospectively, in order to review our past experience, and to examine, whether a subgroup of patients could be identified, in whom invasive haemodynamic measurements were dispensable due to a predictable normal result. 95 patients (14.9%) had precapillary pulmonary hypertension, 44 (6.9%) already at rest, 51 (8.0%) on exercise only. In contrast, 276 patients (43.3%) had pulmonary hypertension secondary to abnormal left ventricular function, 67 (10.6%) at rest, 209 (32.8%) on exercise only. In order to characterize a subgroup of patients, in whom precapillary pulmonary hypertension is very unlikely to be present, and in whom, therefore, right heart catheterization could be regarded as dispensable, a discriminant analysis was performed. By these means a discriminant function using FEV1, PaO2, DLCO - both on exercise - and RV/TLC as discriminant variables was obtained which can provide a qualitative prediction of precapillary pulmonary hypertension with a high sensitivity (at least 95%) and an acceptable specificity (approximately 50%). The usefulness of such a prediction was verified in a subsequent group of 71 patients. Precapillary pulmonary hypertension was correctly predicted in all cases; the specificity was 55%. It is concluded, that right heart catheterization has its value in the pre-operative evaluation of candidates for pulmonary resection due to a high prevalence of compromised haemodynamics, and that patients with a negligible risk of having precapillary pulmonary hypertension can be identified by means of non-invasive functional measurements.