Male Sex Associated With RV Dysfunction in Group 3 Pulmonary Hypertension

A study has found that male sex may be predictive of right ventricular (RV) dysfunction in patients with pulmonary hypertension (PH) caused by chronic lung disease (group 3 PH). Additionally, the presence of RV dysfunction or RV fractional area change (RVFAC) of <28% may help identify those with group 3 PH who are at risk for poor outcomes. Findings from this study were published in the Journal of the American Heart Association.

Patients with group 3 PH (≤18 years of age) from the Minnesota Pulmonary Hypertension Repository at the University of Minnesota were included in the cohort study (n=147). Patients were categorized as having group 3 PH if they had mean pulmonary arterial pressure ≥25 mmHg at rest and pulmonary capillary wedge pressure ≤15 mmHg and had chronic obstructive lung disease, interstitial lung disease, combined pulmonary fibrosis and emphysema, and/or obesity-related lung disease.

The researchers assessed and quantified RV systolic function using RVFAC as well as ⁺dP/dt_max/instantaneous pressure. The 2 variables that characterized RV diastolic function were Tau and RV diastolic stiffness.

Kaplan-Meier and Cox proportional hazards analyses were used to predict which patients would not experience heart failure hospitalization and death.

In the analysis adjusted for pulmonary vascular resistance and pulmonary arterial compliance, the strongest predictor of lower RVFAC was male sex. Compared with females, males had significantly lower RVFAC (31% vs 26%, respectively; P =.03) overall and also had lower RVFAC mean pulmonary arterial pressure and pulmonary vascular resistance values.

As pulmonary vascular resistance increased in males, ⁺dP/dt_max/instantaneous pressure decreased, a relationship not observed in females. Additionally, males with RVFAC <28% had a significantly increased risk for heart failure hospitalization or death compared with females (hazard ratio, 1.84; 95% CI, 1.04–3.10; P =.035).

Limitations of the study include its relatively small patient population, the recruitment of patients from a single center, the retrospective inclusion of approximately half of the cohort, and the observational nature of the analysis.

“In summary, sex hormones, though not measured in our cohort, are strongly linked to RV function and adaption,” the researchers wrote, “and future studies may elucidate how manipulation of sex hormones may combat RV dysfunction in group 3 PH and beyond.”

Reference

Prins KW, Rose L, Archer SL, et al. Clinical determinants and prognostic implications of right ventricular dysfunction in pulmonary hypertension caused by chronic lung disease. J Am Heart Assoc. 2019;8(2):e011464.