Electrocardiographic and Hemodynamic Correlations in Primary Pulmonary Hypertension

Abstract

In order to evaluate the pulmonary hemodynamics in primary pulmonary hypertension, the relation between the standard 12-lead electrocardiogram (ECG) and pulmonary hemodynamics as determined by right-heart catheteriza tion was analyzed. Significant positive correlations were noted between ampli tude of the R in V1, the R/S ratio in V1, and the pulmonary artery systolic pressure (r=0.46 and 0.50, respectively, p < 0.01). An amplitude of the R in V1 of more than 1.2 mV indicated a pulmonary artery systolic pressure of more than 90 mmHg with a sensitivity of 94% and a specificity of 47%. The cardiac index showed a significant positive relationship with amplitude of the R in V5 and V6 and the R/S ratio in Vs and V6 (r = 0.46, 0.46, 0.39, and 0.48, respec tively ; each with a p < 0.01). Moreover, an ÂQRS ≥ 100°, and either an SV6 ≥ 0.7 mV, or R/SV 6 ≤ 2 indicated a cardiac index of < 2.8L/min/m2 with a sensitivity of 82% and 84% and a specificity of 86% and 100% respectively. This study suggests, therefore, that the 12-lead ECG is useful for the evalua tion of the severity of pulmonary hypertension by its ability to predict pulmo nary artery systolic pressure and cardiac index with clinically useful accuracy.