Arterial Vascular Pruning, Right Ventricular Size and Clinical Outcomes in COPD

Citation:

Washko GR, Nardelli P, Ash SY, Vegas Sanchez-Ferrero G, Rahaghi FN, Come CE, Dransfield MT, Kalhan R, Han MLK, Bhatt S, et al. Arterial Vascular Pruning, Right Ventricular Size and Clinical Outcomes in COPD. Am J Respir Crit Care Med. 2019.

Date Published:

2019 Feb 13

Abstract:

BACKGROUND: Cor pulmonale (right ventricular dilation) and cor pulmonale parvus (right ventricular shrinkage) are both described in chronic obstructive pulmonary disease (COPD). The identification of emphysema as a shared risk factor suggests that additional disease characterization is needed to understand these widely divergent cardiac processes. Here, we explored the relationship between CT measures of emphysema and distal pulmonary arterial morphology with RV volume, as well as their association with exercise capacity and mortality in ever-smokers with COPD enrolled in the COPDGene Study. METHODS: Epicardial (myocardium and chamber) RV volume (RVEV), distal pulmonary arterial blood vessel volume (arterial BV5: vessels <5mm2 in cross section) as well as objective measures of emphysema were extracted from 3,506 COPDGene CT scans. Multivariable linear and Cox regression models as well as the log rank test were used to explore the association between emphysema, arterial BV5 and RVEV with exercise capacity (6-MWD) and all-cause mortality. RESULTS: The RVEV was approximately 10% smaller in GOLD 4 vs GOLD 1 COPD (P<0.0001). In multivariable modeling, a 10mL decrease in arterial BV5 (pruning) was associated with a 1mL increase in RVEV. For a given amount of emphysema, relative preservation of the arterial BV5 was associated with a smaller RVEV. An increased RVEV was associated with reduced 6-MWD and in those with arterial pruning an increased mortality. CONCLUSIONS: Pulmonary arterial pruning is associated with clinically significant increases in right ventricular volume in smokers with COPD and is related to exercise capacity and mortality in COPD.