Summary

Background: Data regarding the epidemiology of secondary pulmonary hypertension are scanty.

Objectives: To describe the spectrum and relative incidence of background diseases in patients with significant secondary PHT.

Methods: We identified 671 patients with systolic pulmonary artery pressure of 45 mm Hg or more from the database of the echocardiographic laboratory. Their background diseases were recorded and classified into three subgroups: cardiac, pulmonary and pulmonary vascular disease without pulmonary parenchymal disease. Age at the first echocardiographic study, gender and systolic PAP values were recorded. Data between the three subgroups were compared.

Results: The mean age of the patients was 6515 years, mean systolic PAP 6114 mm Hg and female:male ratio 1.21:1. At the time of diagnosis 85% of the patients were older than 50. PHT was secondary to cardiac disease in 579 patients (86.3%), to PVD without PPD in 54 patients (8%) and to PPD in only 38 patients (5.7%). Mean age and mean systolic PAP did not differ significantly among the three subgroups. There was a significantly higher female: male ratio in patients with PVD without PPD compared with cardiac or pulmonary diseases (1.7:1 vs. 1.2:1 and 1.7 vs. 0.8:1 respectively, P0.05).

Conclusions: The majority of patients with significant PHT are elderly with heart disease. PVD without PPD and chronic PPD are a relatively uncommon cause of significant PHT. Since the diagnosis of PHT is of clinical significance and sometimes merits different therapeutic interventions, we recommend screening by Doppler echocardiography for patients with high risk background diseases.