Background: When elevated pulmonary artery pressure (PAP) is assessed by echocardiography, right heart morphology is always considered. The goal of this study was to evaluate how right heart geometry changes with increasing right ventricular pressure load.
Subjects and methods: Data from patients undergoing transthoracic echocardiography with subsequent right heart catheterization within a time period of 6 months were retrospectively analysed. First, Spearman-rho coefficients between mean PAP and right heart parameters were calculated. Second, the population was divided into tertiles according to mean PAP and Kruskal-Wallis variance analysis between variables was performed.
Results: Fifty-four patients (23 female, median age 77 years, IQ range 63-83) were selected. Mean PAP (median 27 mmHg, IQ range 24-36), right atrial (RA) dilatation (median 1, IQ range 0-2), tricuspid insufficiency (TI) severity (median 1.5, IQ range 0-2) and right ventricular (RV) dilatation (median 0, IQ range 0) were included. Significant correlations with mean PAP were found for RA dilatation (rho = 0.380; P = 0.005) and TI severity (rho = 0.294; P = 0.032). No correlation with RV dilatation could be shown (rho = 0.241; P = 0.081). Across the tertiles [(1) mean PAP 25 mmHg; (2) mean PAP 26-30 mmHg; (3) mean PAP > or = 31 mmHg)], variance analysis showed a significant increase in RA dilatation (P = 0.009) and TI severity (P = 0.040). No change in RV dilatation across groups was observed (P = 0.216).
Conclusions: RA dilatation and TI severity significantly increase with increasing RV pressure load. No increase in RV dilatation was observed in the studied population. Hence, absence of RV dilatation does not exclude the presence of elevated PAP.