Cardiac rehabilitation after PCI positively affects endothelial function
Cardiac rehabilitation appears to improve endothelial function in patients who have undergone percutaneous coronary intervention, being equally beneficial in acute coronary syndrome (ACS) and stable angina patients, according to a team of South Korea-based investigators.
In a cohort of 119 patients (mean age 54.9 years; 87.4 percent male) who received successful PCI for their coronary disease and attended a cardiac rehabilitation programme after discharge, the investigators found that flow-mediated dilation (FMD), a measure of endothelial function, significantly improved after 6 months (9.0 percent from 7.9 percent at baseline). [APSC 2017, abstract MP-20]
When patients were grouped according to PCI indication, baseline FMD was lower in patients with acute coronary syndrome (ACS; n=69) than in those with stable angina (n=50), although the difference was not significant (7.7 vs 8.1 percent; p=0.180). The beneficial effect of cardiac rehabilitation on FMD was noted equally in both patient subgroups, yielding an increase of around 1.1 percent at 6-month follow-up.
FMD at 6 months was 8.9 percent in the ACS subgroup and 9.2 percent in the stable angina subgroup, with no significant between-group difference (p=0.61).
Other notable improvements observed after 6 months of cardiac rehabilitation included low-density lipoprotein cholesterol (116.9 to 82.7 mg/dL), high sensitivity C-reactive protein (0.87 to 0.23 mg/L) and maximal aerobic capacity (29.2 to 31.9 ml/kg/min).
“Our results support that improvement of endothelial function is one of the important effect of cardiac rehabilitation, reducing cardiovascular risk for ACS and stable angina,” the investigators said, noting that cardiac rehabilitation is equally beneficial to ACS and angina patients in terms of improving FMD.
One of the largest organs of human body, the endothelium interacts with nearly every system in the body and has been implicated in end-organ diseases of systems including neurologic, renal, hepatic, vascular, dermatologic, immunologic and cardiac. It plays a crucial role in providing haemostatic balance, formation of blood vessels, and regulation of coagulation and vascular tone. [Glob Cardiol Sci Pract 2014;3:291–308]
Given the key functions of the endothelium, endothelial function has been considered a barometer for cardiovascular risk. A shift in the actions of the organ toward reduced vasodilation, a proinflammatory state and prothrombic properties—also known as endothelial dysfunction—is reported to be the initial step in the pathogenesis of peripheral arterial disease, cardiovascular diseases and stroke, among others. [Int J Biol Sci 2013;9:1057-1069]
Exercise has been widely reported as one of the potential interventions to improve or ameliorate endothelial dysfunction. Regular moderate physical activity is said to promote an antioxidant state and preserve endothelial function. [Sports Med 2009;39:797-812; Nitric Oxide 2015;45:7-14]
That exercise may have a beneficial effect on the development of cardiovascular disease through preserving endothelial function is supported by the fact that every recent major evidence-based guideline regarding the management and prevention of coronary heart disease provides a class 1 level recommendation for referral to a cardiac rehabilitation programme, the investigators said.