THE IMPACT OF PRESSURE RECOVERY ADJUSTMENT ON AORTIC VALVE AREA DISEASE SEVERITY IN TRANSCATHETER AORTIC VALVE REPLACEMENT PATIENTS

Introduction Pressure recovery (PR) in aortic stenosis (AS) occurrence has been studied since the late 1980’s as specific cases applicable only to small or low-normal ranges aortas. [1] Interest regarding PR has increased significantly in recent years. [2-3] The aim of our study is to determine the impact of PR adjustment on disease severity in patients with severe AS by traditional grading methods. We hypothesize that accounting for PR will result in a reclassification of aortic stenosis severity in a significant number of patients. Methods After institutional board approval, we performed a retrospective single center study on patients who underwent TAVR at Tufts Medical center between October 2012 to February 2021. Standard measurements and mean transaortic gradients were obtained by pre-procedure transthoracic echocardiograms. Aortic valve areas (AVA) were calculated using the continuity equation. PR and PR adjusted AVA were calculated using previously validated equations. [4-5] Sinotubular junction (STJ) size was obtained from pre-procedural computerized tomography (CT) scans. Results Patient characteristics are shown in Table 1. A total of 544 patients were evaluated after excluding patients greater than mild mitral or aortic regurgitation. The absolute value of pressure PR recovery was significantly different between the reclassified groups. (p-value = 0.02) Using PR adjusted AVA resulted in the reclassification of 109 patients (25.05%) from severe to moderate aortic stenosis (AVA >1 cm2). Of the 109 patients who were reclassified, 36 patients (33.02%) had STJ diameters >3.0 cm. (Table 1) Discussion Adjusting calculated AVA for PR resulted in a reclassification of a significant number of adult patients from severe to moderate aortic stenosis. PR was significantly larger in patients who reclassified from severe to moderate aortic stenosis after adjusting for PR. There was no difference in STJ diameter between the PR adjusted groups. Our data suggests that those patients most vulnerable to reclassification with PR adjustment are those with the largest calculated “severe” aortic valve areas, rather than those with particular aortic root dimensions.