The prognostic role of the ECG in primary pulmonary hypertension

BACKGROUND/RATIONALE: Doppler echocardiography and invasive hemodynamic parameters reflective of right ventricular failure are associated with a poor prognosis in patients with primary pulmonary hypertension (PPH). The aims of the present study were to examine whether ECG features in patients with PPH are associated with a decrease in survival, and to determine the value of the ECG in risk stratification. METHODS/RESULTS: We analyzed the ECG, New York Heart Association (NYHA) class, and hemodynamic parameters in 51 untreated patients with PPH (88% women; mean age, 41.7 years; 79% NYHA classes III and IV) evaluated between 1992 and 1998. Subsequent treatment included epoprostenol in 37 patients, calcium channel blockers in 10 patients, epoprostenol and atrial septostomy in 2 patients, and lung transplant in 3 patients. As of 1999, 16 patients had died. Based on Kaplan-Meier estimates, median survival was > 6.5 years and estimated survival at 1 year, 3 years, and 5 years was 86%, 71%, and 57%, respectively. Significant predictors of decreased survival by Cox regression analysis include pulmonary vascular resistance (PVR; hazard ratio [HR], 1.11 per Wood unit), cardiac index (HR, 0.22 per L/min/m(2)), p wave amplitude in lead II (HR, 3.06 per mm), p > or = 0.25 mV in lead II (HR, 2.77), qR in V(1) (HR, 3.55), and World Health Organization criteria for right ventricular hypertrophy (HR, 4.26). After controlling for PVR, the HRs attributable to the ECG criteria were only slightly diminished. NYHA class and pulmonary artery pressures did not correlate with a decrease in survival. CONCLUSIONS: ECG parameters reflective of physiologic and anatomic abnormalities in the right ventricle are associated with decreased survival in patients with PPH, and may be useful for deciding therapeutic choices including the timing for lung transplantation listing.