The effect of a cardiac rehabilitation programme on carotid stiffness and haemodynamic properties of patients diagnosed with a transient ischaemic attack : a pilot study : compiled by Brandon Woolley for the degree of Master of Health Science in Sport and Exercise Science from Massey University, Wellington

Abstract

Arterial stiffness is associated with cardiovascular risk factors (e.g., hypertension, abnormal blood lipids and lipoproteins, physical inactivity and obesity) and the existence of atherosclerosis, and is identified as an independent risk factor for coronary artery disease and ischaemic stroke. The common carotid artery is the major conduit supplying blood to the brain is of particular interest. Research has demonstrated that interventions, which target the aforementioned risk factors, reduce the risk of occurring vascular events. The aims of this study were to 1) identify whether an 8-week cardiac rehabilitation programme reduces the stiffness of the common carotid artery, as determined by changes in arterial compliance, distensibility and stiffness index β, in transient ischaemic attack (TIA), and; 2) investigate the relationship between changes to arterial stiffness and haemodynamic properties of the common carotid artery. Eighteen male and female participants (mean ± SD; 65 ± 11 y, 1.72 ± 0.07 m, 85.6 ± 11.5 kg) recruited within a 14 day period following a TIA, volunteered to take part in the present study. Initial risk stratification assessments (i.e., cholesterol, glucose, ECG, etc) were completed prior to assessing arterial stiffness and haemodynamic properties. An ultrasound device was used to obtain arterial measures while participants were rested and in a supine position. Participants were then randomised to either an exercise (EX; 8-week intervention), or to a usual-care control (CON) condition. Identical vascular measures were obtained post-intervention. Results revealed a significant Test by Condition interaction for arterial compliance, distensibility and stiffness index β, and for compliance and distensibility following the 8-week exercise intervention (all P < 0.05). Post-hoc analysis demonstrated a significantly greater change in compliance and distensibility for the EX condition. No significant changes were observed in arterial haemodynamic properties or CAD risk stratification measures. The present study has demonstrated that exercise leads to improved vascular health, as determined by a decrease in arterial stiffness, thus potentially leading to a reduced risk of an ensuing or recurring cardio- or cerebrovascular event.