Understanding the mechanism of improved CFR after TAVR/SAVR – the importance of basal flow

Aortic stenosis (AS) induces left ventricular (LV) hypertrophy by imposing a pressure load at the valve level. Haemodynamic stress along with increased mass changes the density of the myocardial capillary bed and resistances to myocardial flow; at times, this may result in a mismatch of myocardial oxygen supply/demand, which may explain inducible ischaemia despite normal coronary arteries. Relief of the valvular stenosis should, in theory,  ameliorate such myocardial changes over time, resulting in improved LV function, reduced LV mass, and better coronary physiology, manifesting in an improved coronary flow reserve (CFR) (Figure 1). Envisioning this response is easy, proving ...