Cardiovascular function during cognitive stress in men before and after coronary artery bypass grafts

Cardiovascular function during cognitive stress using the Stroop Color Test (SCWT) was documented in 25 men with ischemic heart disease (IHD) before and after coronary artery bypass grafting (CABG). Impedance cardiography was used to measure changes from resting baseline in heart rate (HR), stroke volume (SV), cardiac output (CO), myocardial contractility, and total peripheral resistance (TPR). Cognitive stress was associated with significant increases in HR, blood pressure, SV, CO, and myocardial contractility. TPR did not change from resting baseline during cognitive stress before CABG. However, TPR decreased significantly from resting baseline during cognitive stress after CABG. These findings support the theory that cognitive stress is associated with a significant increase in myocardial oxygen demand.