Impact of coronary artery disease on contractile function and ventricular‐arterial coupling during exercise: Simultaneous assessment of left‐ventricular pressure–volume and coronary pressure and flow during cardiac catheterization

Coronary artery disease (CAD) can adversely affect left ventricular (LV) performance during exercise by impairment of contractile function in the presence of increasing afterload. By performing invasive measures of LV pressure–volume and coronary pressure and flow during exercise, we sought to accurately measure this with comparison to the control group. Sixteen patients, with CCS class >II angina and CAD underwent invasive simultaneous measurement of left ventricular pressure–volume and coronary pressure and flow velocity during cardiac catheterization. Measurements performed at rest were compared with peak exercise using bicycle ergometry. The LV contractile function was measured invasively using the end‐systolic pressure–volume relationship, a load independent marker of contractile function (Ees). Vascular afterload forces were derived from the ratio of LV end‐systolic pressure to stroke volume to generate arterial elastance (Ea). These were combined to assess cardiovascular performance (ventricular‐arterial [VA] coupling ratio [Ea/Ees]). Eleven patients demonstrated flow‐limiting (FL) CAD (hyperemic Pd/Pa