Figure 1.

Diastolic dysfunction (DD) gets significantly affected by the negative impact of cross-clamp period and the cardiopulmonary bypass pump circuit post-AVR. This is true especially in patients with more severe diastolic dysfunction preoperatively. Grade 3 DD may be converted to Grade 4 DD after the AVR procedure in these susceptible patients as shown in the schematic diagram. With rapid decline in afterload compared to preop, left ventricular (LV) end diastolic volume may become as close to being emptied in a hyperdynamic hypertrophic LV. Such LV now depends much more on diastolic filling in order to keep up with low blood pressure and cardiac output especially involving the susceptible marginal zone, which in turn causes ineffective diastolic filling.