An unusual complication after transcatheter aortic valve implantation: a case report.

Background: Ventricular septal defect (VSD) is an unusual complication of transcatheter aortic valve implantation (TAVI). The risk factors are not well understood but may include oversizing, calcification amount and location, left-ventricular chamber morphology, and valve-in-valve (ViV) procedures. Percutaneous treatment is challenging but is usually the preferred option.

Case Summary: An 80-year-old woman with two previous surgical aortic valve replacements was admitted to our Cardiology Department for decompensated heart failure. New bioprosthesis degeneration (19 mm Mitroflow™, Sorin Group, Canada) was observed with severe intraprosthetic aortic regurgitation. After evaluation, the heart team chose to perform ViV TAVI. Because of the high risk of coronary obstruction, chimney stenting of both coronary arteries was performed. A 23 mm self-expandable Navitor™ valve (Abbott, IL, USA) was implanted, but the Mitroflow™ valve had to be cracked to minimize the persistent high gradient. During valve fracture, the non-compliant balloon broke and a small iatrogenic VSD appeared. However, the patient remained stable, so conservative management was selected. During follow-up, she developed severe haemolytic anaemia and heart failure; therefore, percutaneous closure of the iatrogenic VSD was performed twice, which was a difficult challenge.

Discussion: A viable alternative to redo surgery is ViV TAVI. Risks include higher rates of prosthesis-patient mismatch and coronary obstruction. Occasionally, bioprosthetic valve fracture is required, particularly in small bioprostheses, to achieve low gradients. Anecdotally, fracture has led to annular rupture and VSD. Most VSDs are small and without clinical or haemodynamic repercussions; however, in symptomatic cases, percutaneous closure is a viable alternative to surgery.