A retrospective clinical study was made in 50 patients (21 male, 29 female, mean age 29 +/- 12 years) with clinical primary pulmonary hypertension (CPPH). The mean interval from symptom onset to diagnosis was 4.07 +/- 3.84 years. The most frequent symptoms were dyspnea and palpitation. Increased pulmonic second heart sound (P2) and right-sided third and/or fourth heart sounds were found in 90% and 30% of patients respectively. Electrocardiography showed right ventricular hypertrophy (86%) and underlying sinus rhythm (100%). Echocardiography showed right ventricular enlargement (78%) and tricuspid regurgitation (44%). Chest film showed prominent main pulmonary artery (90%) and right heart enlargement (82%), but it was normal in 5% of the patients. Hemodynamic study (n = 30) showed three-fold increase in mean pulmonary artery pressure (MPAP) (8.53 +/- 2.00 kPa, 1 kPa = 7.5 mmHg), mild to moderate elevation in mean right atrial pressure (MRAP) (1.60 +/- 0.80 kPa). Patients with functional class (NYHA) 3-4 had relatively higher MPAP (8.53 +/- 2.00 vs 7.73 +/- 3.20 kPa) and MRAP (1.87 +/- 2.40 vs 0.93 +/- 0.93 kPa) than those with class 1-2. Patients with class 3-4 common in female (71%) than in male (29%), P < 0.05. During a mean period of 3.8 years of follow-up in 17 patients, 10 died of right ventricular failure and 3 of sudden death; the MPAPs of the dead were 6.13-9.60 kPa (mean 7.84 kPa).
Conclusion: CPPH patients had severe symptoms and remarkable physical or laboratory abnormalities when the disease was diagnosed. The long interval from appearance of symptoms to establishment of diagnosis emphasized the importance of being conscious of such a condition.