Pathophysiological Factors Associated with Left Ventricular Perforation in Transcatheter Aortic Valve Implantation by Transfemoral Approach.

BACKGROUND AND AIM OF THE STUDY: Left ventricular (LV) perforation is one of the rare and most serious complications of transcatheter aortic valve implantation (TAVI). The study aim was to determine the pathophysiological factors associated with this serious complication.

METHODS: A retrospective study was conducted of pathophysiological factors shown in echocardiograms and computed tomography angiograms performed preoperatively in patients who developed LV perforation during transfemoral TAVI (study group) with regards to anatomic and functional variables. Results were then compared with data acquired from a randomly selected sample of patients without perforation (control group). Among 963 TAVI cases, LV perforation occurred in 11 patients (three males, eight females; mean age 79 years). These patients showed complications of LV perforation that required emergency sternotomy and repair of injury to the left ventricle. Ten patients were rescued by the procedure, but one patient died during surgery.

RESULTS: Focus on preoperative factors and intraoperative steps was established in favor to identify possible predictors of LV perforation. A LV cavity size <4.2 cm and a hypercontractile ventricle were identified in 10 patients (90%). Only one patient had a dilated cardiomyopathic left ventricle, with a cavity size of 6.1 cm and an ejection fraction of 10%. The present study results revealed other specific patient-related factors, namely a narrow aorto-mitral angle and a thin ventricular muscular wall despite long-standing aortic stenosis. All 11 patients had an average mid-LV muscular wall thickness of 5 mm. An inverse proportional relationship between the aorto-mitral angle and the incidence of perforation was noted, where in all 11 patients the wire had directed itself towards the anterior free wall of the left ventricle, where it induced injury.

CONCLUSIONS: A small LV cavity, a hypercontractile state, a thin muscular wall, and a narrow aorto-mitral angle may be considered potential predictors of the occurrence of LV perforation during TAVI.