Feasibility Of Diagnosis In Patients With Chronic Cor Pulmonale By Doppler Echocardiography

【Objective】The most common cause of chronic cor pulmonale is chronic lung disease. Pulmonary hypertension is a necessary condition for diagnosis in chronic cor pulmonale. At present, Doppler Echocardiography(DE), as the most convenient noninvasive methods, was generally used to estimate pulmonary artery pressure in clinical practice. But no studies confirmed whether Doppler Echocardiography can evaluation pulmonary artery pressure accurately and comprehensively in chronic lung disease patients. We design this study to examine the performance characteristics of DE-estimated sPAP in establishing or excluding a diagnosis of chronic cor pulmonale , using right heart catheterization as a gold standard .【Methods】Consecutive patients with suspectd chronic cor pulmonale who underwent DE and RHC within 48 hours in Cardio-Pulmonary Circulation Center of Shanghai Pulmonary Hospital from May 2008 to April 2011 were enrolled. Sensitivity, specificity, positive and negative predictive values of sPAP estimated by DE and RHC were calculated in all patients and COPD patients. Secondly, to estimate the Sensitivity, specificity, positive and negative predictive values between DE diagnosis PH accompany right heart expansion and RHC diagnosis PH. Finally, to evaluate the correlation and accuracy between estimated by DE and measured sPAP by RHC.【Results】1. 67 patients were enrolled in the study. They were all suspected chronic cor pulmonale. Sensitivity, specificity, positive and negative predictive values of DE diagnosis PH were respectively 87.8%,53.8%,75% and 73.7%. Sensitivity, specificity, positive and negative predictive values of DE diagnosis PH in COPD patients were 90.5%,55.6%,70.3% and 83.3%.. 2.Sensitivity, specificity, positive and negative predictive values of DE diagnosis PH accompany right heart expansion patients were respectively 77.8%, 66.7%, 87.5% and 50%.3.The correlation between sPAP estimated by DE and measured by RHC was good(r=0.717,P<0.001),however, only 53%of pressure estimations were found to be accurate (less than 10mmHg difference compared with measured pressure), Moreover, 14%studies revealed a difference between DE estimated and RHC measured sPAP of more than 20 mm Hg.【Conclusions】1.Estimation of sPAP by DE is frequently inaccurate (i.e., discrepant by at least 10mmHg) in patients with chronic lung disease for the poor specificity.2. Sensitivity and specificity of DE estimated COPD and PH increased, but RHC was still needed for its poor specificity.3. Although DE estimated sPAP accompany right ventricular abnormalities can increase sensitivity and specificity slightly, reliance on this noninvasive technique can potentially lead to overdiagnosis of PH, the diagnosis should be confirmed by RHC.4. Right heart enlargement present in some patients with chronic lung disease not accompanied with pulmonary hypertension suggests that some other unknown reason leading to right heart enlargement may exist except increased pulmonary arterial pressure for these patients.5. Despite a statistically significant correlation with directly measured values, estimation of sPAP by echocardiography is frequently inaccurate in patients with chronic lung disease and leads to considerable overdiagnosis of PH.