Poor Correlation of Estimated Pulmonary Artery Systolic Pressure Between Echocardiography and Right Heart Catheterization in Patients Awaiting Cardiac Transplantation: Results From the Clinical Arena

Background: Pulmonary arterial pressure measurement is an integral part of the pre-heart transplant evaluation. In the clinical arena, the correlation and agreement between pulmonary artery systolic pressure (PASP) measured by Doppler echocardiography versus catheterization in pre-heart transplant patients has not been studied. Methods: Data on all patients evaluated for heart transplantation at our program between 2003 and 2005 (n = 176) were retrospectively reviewed. Patients with both transthoracic echocardiography (with interpretable images) and right heart catheterization performed were included (n = 108; mean time difference, 2.2 days; median, 2 days). The tricuspid valve regurgitant jet was identified by color flow Doppler and jet maximum velocity was measured by continuous wave Doppler. The PASP was estimated by using the modified Bernoulli equation and adding right atrial pressure. We correlated echocardiographically estimated PASP with that measured by right heart catheterization. Results: Mean estimated PASP by echocardiography was 46.6 ± 13.7 mmHg versus 44.8 ± 17.9 mmHg by right heart catheterization (P = NS). However, the correlation between echocardiographic and measured PASP was poor (r = 0.49, P < .001). The correlation was poor in both ischemic and nonischemic cardiomyopathy. Conclusion: Among patients referred for heart transplant evaluation, there is poor agreement and correlation between echocardiographically estimated PASP and values obtained by right heart catheterization. Furthermore, echocardiographically obtained estimates of PASP should not be exclusively relied upon to exclude heart transplant recipient candidates.