Electrocardiographic and Hemodynamic Correlations in Primary Pulmonary Hypertension.

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 catheterization was analyzed. Significant positive correlations were noted between amplitude 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 V₅ and V₆ (r=0.46, 0.46, 0.39, and 0.48, respectively; each with a p < 0.01). Moreover, an ÂQRS ≥ 100°, and either an SV₆ ≥ 0.7 mV, or R/SV₆ ≤ 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 evaluation of the severity of pulmonary hypertension by its ability to predict pulmonary artery systolic pressure and cardiac index with clinically useful accuracy. [ABSTRACT FROM AUTHOR]