A Highly Mobile Mass in the Anterior Left Ventricular Outflow Tract Immediately Beneath a Heavily Calcified, Stenotic Aortic Valve: Vegetation, Thrombus, or Neoplasm?

Treatment of severe aortic stenosis and left ventricular outflow tract mass with transcutaneous aortic valve implantation: a case report

Background

Percutaneous implantation of aortic valve for severe aortic stenosis (AS) in the presence of pedunculated mobile left ventricular outflow tract (LVOT) mass not reported before. In this case report, we address the feasibility of this procedure.

Case summary

An 80-year-old patient who presented with presyncope, transthoracic echocardiogram (TTE), and transoesophageal echocardiography (TOE) revealed severe calcific AS and LVOT mass measuring 2.1*1.5 cm. The patient was turned down for surgery. It was decided that transcatheter aortic valve implantation (TAVI) be performed because the valve compresses the mass against the proximal part of the interventricular septum. The mass peduncle was 1.4 cm, and it was 4 mm away from the annulus. This meant the valve was needed to be deployed 18 mm below the annulus to cover the mass completely. Gentle manipulation and direct valve deployment without preballoon dilation to decrease the possibility of fragment embolization were necessary. Self-expandable core valve deployed as low as possible, after initial deployment, the distance of LVOT covered by the valve measured by TOE 1.66 cm, the whole mass was covered, then the valve was fully deployed. The patient was extubated in the catheterization room; there was no clinical evidence of embolization. The patient was discharged home after 2 days. A follow-up TTE after 6 months showed a well-functioning valve and the LVOT mass then disappeared.

Discussion

Pedunculated LVOT mass should be resected surgically. In high-risk surgical patients, direct TAVI to compress the mass is feasible in experienced canters. The safety issues need more research and more cases to judge. Transoesophageal echocardiography during the procedure is mandatory to guide the valve position.