Lung structure and longitudinal change in cardiac structure and function: the MESA COPD Study.

Background: Lung structure and cardiac structure and function are associated cross-sectionally. The classic literature suggests relationships of airways disease to cor pulmonale and emphysema to reduced cardiac output (CO) but longitudinal data are lacking.

Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study was a multicentre longitudinal COPD case-control study of participants 50-79 years with ≥10 pack-years smoking without clinical cardiovascular disease. Segmental airway wall area (WA) and percent emphysema were measured on computed tomography. Right and left ventricle parameters were assessed on cardiac magnetic resonance imaging (cMRI) in exams 6 years apart. Longitudinal and period cross-sectional associations were evaluated with mixed models adjusted for demographics, body size and smoking.

Results: The 187 participants with repeated cMRI were 67±7 years old; 42% had COPD; 22% currently smoked; and the race/ethnicity distribution was 54% White, 30% Black, 14% Hispanic and 3% Asian. Greater WA at enrolment was associated with longitudinal increase in right ventricular (RV) mass (3.5 (95% CI 1.1-5.9) g per 10 mm WA). Greater percent emphysema was associated with stably lower left ventricular (LV) end-diastolic volume (-7.8 (95% CI -10.3- -3.0) mL per 5% emphysema) and CO (-0.2 (95% CI -0.4- -0.1) L·min per 5% emphysema).

Conclusion: Cardiac associations varied by lung structure over 6 years in this multi-ethnic study. Greater WA at enrolment was associated with longitudinal increases in RV mass, whereas greater percent emphysema was associated with stable decrements in LV filling and CO.