Background: Aortic stenosis imposes a chronic pressure overload on the left ventricle, with attendant adaptations in hemodynamics, muscle mass and performance. The hemodynamic changes that occur during the initial 24 h following abrupt removal of the impediment to left ventricular outflow have not been previously examined.
Methods: A total of 52 patients with right heart catheterization was evaluated before, within 6 h and at 24 h after successful transcatheter aortic valve replacement (TAVR). Echocardiographic data were examined before and within 30 days of the procedure.
Results: TAVR was successful in all 52 patients, and at 24 h after the procedure resulted in: (i) an increase in cardiac index (CI) (from 2.0 ± 0.6 to 3.1 ± 0.7 l/min/ m2, p <0.001) and stroke volume (SV) (from 62.3 ± 18.7 to 76.6 ± 21.3 ml, p <0.001); (ii) reductions in systemic vascular resistance (from 1555 ± 458 to 1021 ± 280 dyne·s/cm5, p <0.001) and pulmonary vascular resistance (from 174 ± 150 to 112 ± 76 dyne·s/cm5, p = 0.001); (iii) reductions in pulmonary capillary wedge pressure (from 24.2 ± 6.7 to 19.7 ± 7.3 mmHg, p <0.001), mean pulmonary artery pressure (from 32.2 ± 9.9 to 27.5 ± 8.8 mmHg, p = 0.002) and in central venous pressure (from 13.5 ± 4.8 to 9.4 ± 3.9 mmHg, p <0.001); and (iv) an increase in systolic arterial pressure (from 127 ± 25 to 135 ± 14 mmHg, p = 0.04), along with a decrease in diastolic arterial pressure (from 58 ± 11 to 53 ± 9 mmHg, p = 0.009).
Conclusions: Successful TAVR results in immediate and sizeable improvements in SV and CI, reductions in left and right ventricular filling pressures, and marked reductions in systemic and pulmonary vascular resistances.