Differences in right ventricular morphology, not function, indicate the nature of increased afterload in pulmonary hypertensive subjects with normal left ventricular function.

BACKGROUND

The aim of study was to assess whether a specific morphology of the right ventricle (RV) by 2D echo predicts the hemodynamic nature of pulmonary hypertension (PH).

METHODS

We reviewed clinical, 2D echo, and hemodynamic data of 100 patients with PH: divided into three groups: PH from pulmonary vascular disease (PH ; n = 34) with pulmonary vascular resistance (PVR) > 3 mm Hg/L/min (Wood unit [WU]) and pulmonary artery wedge pressure (PAWP) ≤ 15 mm Hg, pulmonary venous hypertension (PVH; n = 33) with PVR < 3 WU and PAWP > 15 mm Hg and PH (n = 33) with PVR > 3 WU and PAWP > 15 mm Hg. We analyzed several two-dimensional parameters of right heart morphology and function, including the degree of tapering of the RV diameter from base (just above tricuspid annulus) to apex (level of moderator band) in the apical four-chamber view. P = <.05.

RESULTS

Baseline characteristics were similar in all three groups: age 62 ± 14.4 years, 69% females, 57% Caucasians. Hemodynamics and 2D echo data of PH vs PVH vs PH were as follows: PVR 13 ± 6 vs 2 ± 1 vs 7 ± 2 WU, mean pulmonary artery pressure 53 ± 14 vs 34 ± 8 vs 49 ± 8 mm Hg and cardiac index 2.0 ± 0.5 vs 2.8 ± 0.7 vs 2.2 ± 0.7 L/m , RV base/apex ratio during systole (sRV ) 1.3 ± 0.2 vs 2.6 ± 0.5 vs 1.5 ± 0.3. Thus, sRV was twofold higher in the PVH vs PH cohort. On ROC analysis, the AUC for sRV for predicting PVR > 3 WU was 0.873, with optimal cutoff of 1.5.

CONCLUSION

Systolic RV base/apex ratio is a simple 2D index of RV shape that powerfully predicts a PVR > 3 WU and provides powerful discriminating ability between PVH and PH .