Myocardial Perfusion is Compromised in Patients with COPD and Associated with Reduced Functional Capacity

Abstract

Introduction: Chronic Obstructive Pulmonary Disease (COPD) is the 3rd leading cause of death worldwide and carries with it significant cardiovascular mortality. Arterial stiffness is a known risk factor for cardiovascular disease that contributes to worsening myocardial blood flow and limits functional capacity, a marker of disease prognosis and quality of life in COPD. Myocardial perfusion is decided by a careful balance between myocardial blood flow and workload and has been strongly associated with cardiovascular mortality. Despite the convincing relationship between COPD and cardiovascular disease, to date, studies investigating myocardial perfusion and its relationship to functional capacity in COPD remains unexplored. Purpose: This study sought to test the hypothesis that myocardial perfusion is reduced in COPD and associated to functional capacity. Methods: Ten patients with COPD (GOLD Stage II-IV) with no overt signs of cardiovascular disease or diagnosis and 10 demographically matched, apparently healthy controls participated in this study completing a comprehensive analysis of vascular function and functional capacity. Carotid femoral applanation tonometry was used to assess myocardial perfusion (subendocardial viability ratio (SEVR)) and arterial stiffness (Pulse Wave Velocity (PWV)). Functional Capacity was measured via six-minute walk test distance (6MWT) with dyspnea being measured on a 0-10 scale. Results: Patients with COPD exhibited significantly ( p=0.041) reduced myocardial perfusion (SEVR: ΔCOPD=131±19% vs. ΔControl=153±28%) and increased arterial stiffness (PWV: ΔCOPD=8±1 m/s vs. ΔControl=6±1 m/s, p=0.013) when compared to matched controls. Functional Capacity was significantly ( p<0.001) reduced in patients with COPD (6MWT Distance: ΔCOPD=274±87 m vs. ΔControl=476±99 m) while exhibiting significantly ( p=0.02) increased post exercise dyspnea (ΔCOPD=3.1±2.4 vs. ΔControl=0.8±1.2 a.u.). Myocardial perfusion was strongly associated to 6MWT distance ( p=0.038; r=0.693) and arterial stiffness was negatively associated with dyspnea ( p=0.015; r=-0.850). Conclusion: Our data supports that patient with COPD exhibit poor myocardial perfusion that is associated to worse functional capacity, key component of quality of life and mortality in this population. This preliminary data highlights the importance of cardiovascular screening in COPD as it emphasizes how myocardial perfusion impairments may predict prognosis in this population even when no diagnosis of cardiovascular disease is present. Future studies are warranted to investigate if impaired myocardial perfusion plays a causational role in decreasing functional capacity and its potential as a therapeutic target. Supported by American Heart Association (18CDA34110323 PRM & PRE905812 KC/PRM). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.