Effects of Percutaneous Aortic Valve Replacement on Coronary Blood Flow Assessed With Transesophageal Doppler Echocardiography in Patients With Severe Aortic Stenosis

The aim of this study was to assess the change in coronary flow in patients who underwent percutaneous aortic valve replacement (PAVR) for severe aortic stenosis. The left main coronary artery was visualized using transesophageal echocardiography in 17 patients who underwent PAVR. The peak systolic and diastolic velocities of coronary flow and the time-velocity integral were obtained before and after PAVR using pulsed-wave Doppler. The median age was 80.0 years (interquartile range [IQR] 80.0 to 88.0). Median gradients decreased from 40.0 mm Hg (IQR 35.0 to 50.0) before PAVR to 4.0 mm Hg (IQR 2.75 to 4.2) afterward (p <0.001). Aortic valve area increased from 0.6 cm² (IQR 0.5 to 0.7) to 1.9 cm² (IQR 1.7 to 2.0) (p <0.001). Cardiac output increased from 3.3 L/min (IQR 2.4 to 4.0) to 3.6 L/min (IQR 3.1 to 4.4) (p <0.001). Aortic systolic pressure did not change significantly, from 126.0 mm Hg (IQR 11.7 to 137.7) before to 134 mm Hg (IQR 116.3 to 142.5) after valve implantation (p = 0.8). Left ventricular end-diastolic pressure decreased significantly from 19.0 mm Hg (IQR 18.0 to 22.0) before to 14.0 mm Hg (IQR 12.0 to 17.0) after valve implantation (p = 0.01). The medians of the following coronary flow parameters increased significantly after PAVR: peak systolic velocity, 25.0 cm/s (IQR 17.0 to 30.0) to 37.0 cm/s (IQR 23.0 to 44.0) (p <0.001); peak diastolic velocity, 49.0 cm/s (IQR 39.5 to 61.0) to 57.0 cm/s (IQR 42.9 to 83.9) (p = 0.006); total velocity-time integral, 23.7 cm (IQR 15.0 to 27.1) to 28.1 cm (IQR 21.3 to 34.7) (p = 0.001); and systolic velocity-time integral, 5.4 cm (IQR 3.5 to 6.2) to 9.0 cm (IQR 4.5 to 9.8) (p = 0.001). The diastolic time-velocity integral increased from 17.2 cm (IQR 12.0 to 24.0) to 20.1 cm (IQR 15.0 to 25.9) (p = 0.02). In conclusion, after PAVR, there is a significant increase in coronary flow as measured by peak systolic velocity, diastolic velocity, and velocity-time integral using pulsed-wave Doppler by transesophageal echocardiography.