Prevalence of Altered Muscle Metaboreflex among patients after cardiac surgeries

Coronary artery bypass grafting (CABG) is a commonly performed cardiac surgery that improves survival and quality of life in patients with coronary artery disease; however, many patients experience delayed functional recovery, reduced exercise tolerance, and altered cardiovascular responses during physical activity after surgery. These limitations are often linked to autonomic nervous system dysfunction, particularly impairment of the muscle metaboreflex, a key reflex that helps maintain arterial blood pressure and muscle perfusion during exercise by increasing sympathetic activity in response to metabolite accumulation in working muscles. Altered metaboreflex function may result in abnormal heart rate and blood pressure responses, reduced heart rate variability, and early fatigue during exertion, thereby affecting rehabilitation outcomes. The muscle metaboreflex is commonly assessed using post-exercise muscle ischemia, where blood flow to the exercised limb is temporarily occluded with a pneumatic cuff to trap metabolites and isolate the reflex response, while cardiovascular parameters are monitored. Despite the high number of CABG procedures performed in India, data on the prevalence of altered muscle metaboreflex in post-CABG patients remain limited. This study aims to determine its prevalence to support individualized physiotherapy and optimize cardiac rehabilitation strategies.