Right ventricular failure, not airflow limitation, defines outcome in chronic pulmonary disease

Abstract

Right ventricular (RV) dysfunction may drive clinical deterioration in chronic pulmonary disease more than airflow limitation. Persistent pulmonary vascular load induces maladaptive RV remodeling, impaired RV–pulmonary arterial coupling, and subclinical contractile failure, often undetected by conventional echocardiography.

The aim of this study was to determine whether RV myocardial deformation, assessed by global longitudinal strain (RV-GLS), identifies early subclinical dysfunction and independently predicts adverse outcomes in patients with COPD, thereby establishing the right ventricle as a central determinant of disease progression.

Methods

In this prospective study, 146 patients with stable COPD (GOLD II–IV) underwent spirometry, NT-proBNP measurement, 6-minute walk testing (6MWT), and transthoracic echocardiography with RV-GLS. Standard RV functional indices—tricuspid annular plane systolic excursion, fractional area change, and tricuspid regurgitation velocity—were assessed. Patients were followed for 18 months. The primary endpoint was a composite of severe exacerbation, COPD-related hospitalization, or major cardiovascular event. Independent predictors were evaluated using multivariable Cox regression.

Results

Impaired RV-GLS (>−18%) was observed in 32% of patients and frequently preceded abnormalities in conventional systolic indices, which remained preserved in 58% of these cases. RV-GLS correlated with FEV₁, NT-proBNP, and 6MWT distance. During follow-up, 27% of patients experienced the primary endpoint. Impaired RV-GLS conferred a 3.4-fold increased risk of adverse outcomes (HR 3.4; 95% CI 1.8–6.2; p<0.001) and remained independently predictive after adjustment for pulmonary severity and standard echocardiographic measures.

Conclusions

Right ventricular myocardial deformation emerges as a central prognostic axis in COPD. RV-GLS detects early cardiac maladaptation invisible to conventional indices and independently stratifies risk. These findings challenge the lung-centric paradigm, positioning the right ventricle as the principal determinant of outcome. COPD should be reconceptualized as a cardiopulmonary syndrome in which right ventricular dysfunction ultimately dictates clinical trajectory.