Transcatheter Mitral Valve Implantation Using Dedicated Devices: Early Experience Using Different Transapical and Transseptal Devices

Objectives: Transcatheter mitral valve implantation (TMVI) using dedicated devices holds the promise of meeting the clinical need for therapy in high-risk patients suffering from severe mitral regurgitation (MR) who are ineligible for surgery. Preliminary results from an early series are herein reported.

Methods: From 2016 to 2018, a total of 98 patients were screened for TMVI. Of these, 19 (19.4%) high-risk patients (12 males, age 75.9 ± 6.5 years, logEuroSCORE I 30.9 ± 13.1%, all New York Heart Association class III/IV) were found eligible considering anatomical and clinical criteria. Transapical TMVI using Neovasc TIARA (n = 13), Abbott Tendyne (n = 4), or transseptal TMVI using Edwards CardiAQ (n = 2) devices were performed for severe symptomatic functional (n = 12), degenerative (n = 5), or mixed (n = 2) MR. Data from compassionate-use cases (n = 8) are presented in accordance with Mitral Valve Academic Research Consortium definitions.

Results: Immediate technical success was achieved in all patients. Mean procedure and fluoroscopy times were 134 ± 49 and 25.3 ± 18.6 minutes, amount of contrast agent was 60.1 ± 65.5 mL. Intraprocedural left ventricular outflow tract obstruction necessitated device repositioning in one case. All but one patient were extubated in the hybrid OR immediately following the procedure. Mean duration of intensive care and overall hospital stay were 3.7 ± 1.9 and 18.2 ± 4.8 days. Device and procedural success rates at 30 days were 75 and 87.5%, respectively, the first due to one case of cardiogenic shock requiring repeated intensive care unit admissions and one case of cardiopulmonary resuscitation due to ventricular fibrillation, the latter due to one death on day 2. All-cause in-hospital and 30-day mortality was 12.5% (1 of 8) due to right ventricular perforation of a temporary pacemaker lead with subsequent surgical revision and multiorgan failure on day 2. Transthoracic echocardiography upon discharge revealed adequate valve function with no (n = 6) or trace (n = 2) residual MR in all patients and peak/mean transvalvular gradient of 7.9 ± 3.1/2.6 ± 1.4 mm Hg.

Conclusion: In this preliminary series of selected patients, excellent hemodynamic results after TMVI using three dedicated TMVI devices were demonstrated. Careful patient selection by computed tomography and echocardiographic parameters is key for clinical success.