Title
Salvage Transcatheter Aortic Valve Replacement For High-Surgical Risk Severe Aortic Insufficiency
Introduction
Almost 7.8% of patients with severe AI are not operated on because of high mortality risk. TAVR provides an off-label alternative to SAVR for treating AI in high-surgical risk patients. Among Medicare beneficiaries who received AVR for AI, TAVR accounted for about 11%
2 despite no guideline recommendation, signifying a need for a less invasive strategy. The challenges of a TAVR for AI are due to unfavorable anatomical factors constraining prosthesis anchoring: lack of native valve annulus and leaflet calcification, associated aortic root dilation, and large annulus. These challenges pose a risk of prosthesis embolization and migration, paravalvular leak, and residual AI.
Clinical Case
A 65-year-old female with a history of diastolic heart failure, moderate AI, and hypertension presented with worsening dyspnea for several days without chest pain. On presentation she was hypertensive (BP 175/56 mmHg), tachycardic (105 bpm), and hypoxic (SpO2 82%). ECG with ST depressions (V5, V6, I, II, AVL). CXR with cardiomegaly and bilateral pleural effusions. High sensitivity troponin 287 (normal: <14 ng/L). BNP 18,807 (normal: 0-125 pb/ml). BIPAP was placed and started on furosemide, heparin, and nitroglycerin drips. Echocardiogram showed newly reduced EF of 35%, severe AI, severely dilated LA, severely enlarged LV, and moderate pulmonary hypertension. Heart catheterization showed mild to moderate non-obstructive CAD. Cardiac surgery was consulted for SAVR and she was deemed high surgical risk due to frailty and decompensation. Structural team was then consulted for TAVR evaluation, however CTA cardiac showed mild aortic valve calcification. Her clinical status deteriorated rapidly, developing AKI with oliguria requiring dialysis and worsening hypoxic respiratory failure requiring intubation. Bedside echocardiogram showed a worsening severely reduced EF of 10-15%. Impella CP was placed for hemodynamic support and LV off-loading. Despite the lack of adequate aortic valve calcification for prosthesis anchoring the decision was made to proceed with off-label TAVR as a salvage procedure. Successful emergent transfemoral TAVR using a 23mm Edwards Sapien S3. Despite the patient’s critical illness, she gradually improved and was extubated. Repeat echocardiogram demonstrated an improved EF of 35-45%, well-seated prosthetic valve, no paravalvular leak, mild MR, mildly enlarged LV, and moderately enlarged LA. She was discharged to rehab and at one month follow up she reported being back to her usual state of health and functional capacity.
Discussion
Off-label TAVR use for severe AI offers a salvage therapy for critically ill high-risk patients where SAVR is not an option. While challenges do exist in placing prosthetic valves for AI due to unfavorable anatomical factors these challenges will hopefully become less significant with the development of newer devices that have size variability, adaptive seals, and the capability to be repositioned and recaptured. In the hope that as these newer AI-specific prostheses are developed and as TAVR for AI continues to demonstrate its utility, its indication will be added to the guidelines.