TAVI updates: complex valve-in-valve cases

Case Example:

A 71-year-old gentleman had a history of bioprosthetic surgical aortic valve and CABG 12 years prior, presented with NYHA class IV heart failure symptoms. Transthoracic echocardiogram revealed severe left ventricular dysfunction with severe intravalvular aortic regurgitation. Transoesophageal echocardiography (TOE) demonstrated the mechanism of severe aortic regurgitation as degenerative prolapse of the bioprosthetic aortic valve leaflet (Image 1).

During hospitalisation his clinical status deteriorated, he developed fast atrial fibrillation, cardiorenal syndrome, which progressed to cardiogenic shock, requiring haemodialysis and inotropes to stabilise. Following heart team discussion, a surgical redooperation was considered too high risk, given his co-morbidities with worsening clinic status.

Preoperative CT TAVI was performed, with CT reconstruction of the valvular prosthesis, showed a 21mm magna ease valve (Edwards lifescience) with an inner diameter of 18.4mm (image 3). The coronary ostium was located a safe distance 12mm from the aortic annulus indicating a low risk of coronary obstruction. Using the ViV (valve-in-valve) app, preprocedure calculations estimated 18 atmospheres of balloon pressure to adequately expand the valve using an Edwards Sapien 3 (21mm balloon expandable TAVI). The TAVI was implanted via right common femoral artery approach without complication.

After deployment of the TAVI, there was immediate improvement in blood pressure, and clinical status. Following improvement in clinical status, dialysis was weaned when urine output improved, avoiding long-term dialysis. Follow-up transthoracic echocardiogram post procedure, revealed a well seated valve with no AS/AR, subsequently the patient was discharged home.

Key to the procedure is ECGgated-CT aorta, which is the gold standard for pre-procedure planning. CT TAVI evaluates:

1. Annular sizing and valve morphology

2. Vascular access site

3. Coronary artery anatomy, including coronary height and risk of obstruction

4. Ascending aortic root angulation and implantation angle

In valve-in-valve TAVI planning, the annulus diameter is used for valve sizing, and the landing zone is determined to prevent coronary obstruction. These measurements are used to assess feasibility by comparing them with a TAVI valve-in-valve app which gives information on aortic valve implants from the last 20 years. This guides operators on valve size and the amount of pressure needed to expand the valve within the old bioprosthesis.

Following this the access point is chosen, most commonly this is the femoral artery as it is the lowest risk for a vascular complication, a key driver of mortality in early TAVI Trials. Detailed measurement of vessel diameter, tortuosity and calcification are crucial in determining preprocedural vascular risk, given the TAVI sheath insertion profile is 22fr – 26fr (8.4 – 9.2mm).

Conclusion:

Valve-in-valve TAVI is a niche procedure with increasing volume. Given the prevalence of aortic valve disease and improvements in both surgical/percutaneous options, it is expected that more patient will outlive their valvular prothesis. Careful patient selection at heart team discussions and shared decision making with patients on lifetime risks, are important to fully realise the potential of both surgical and percutaneous valve interventions.