Clin Res Cardiol (2021) DOI DOI https://doi.org/10.1007/s00392-021-01843-w

Respect or Resect the Mitral Valve Leaflets in order to Reduce the Risk of Systolic Anterior Motion after Mitral Valve Repair?

A. Raweh1, C. Bountola2, E. Mhanna2, A. Albert1

1Klinik für Thorax-, Herz- und Gefäßchirurgie, Klinikum Dortmund gGmbH, Dortmund; 2Kardiologie, Klinikum Dortmund gGmbH, Dortmund;

Background / Study Objective: The primary lesion resulting in Systolic Anterior Motion (SAM) after mitral valve repair (MVRr) is a mismatch between the mitral valve annular dimension and the amount of leaflet tissue present. This study focuses on the geometry of the mitral valve and the left ventricle as a predictor of SAM after MVRr and how this geometry changes after the repair. To prevent the postoperative SAM in risk patients, multiple surgical techniques are used for resection (Resect) of the leaflet compared to the use of shortened neochordae to displace the tallest portion of the posterior leaflet into the left ventricle (Respect). Does the Respect approach help in preventing SAM after MVRr more than the Resect approach? Methods: Between July 2015 and Mars 2020, a total of 222 consecutive patients underwent mitral valve reconstruction. Patients who underwent concomitant tricuspid valve repair or concomitant coronary artery bypass surgery were included. Patients with primary SAM as a result of hypertrophic obstructive cardiomyopathy or previous mitral valve surgery were excluded. Data were collected in a retrospective manner. Preoperative echocardiography was studied to evaluate the geometry of the mitral valve and left ventricle. Intraoperative and postoperative echocardiography were studied to detect the SAM phenomenon and to evaluate the change in geometry after the repair. We postulated that patient-related and procedure-related parameters could be potentional risk factors for SAM: normal left ventricular function, basal interventricular septum >15 mm, coaptation-septal distance <25mm, anterior leaflet height, posterior leaflet height, aorto-mitral angle <120°, insertion of a small prosthetic ring major reduction in the septo-lateral distance. We postulated that using neochordae to displace the posterior leaflet into the left ventricle instead of resecting a portion of the it can increase the coaptation length and decrease the residual portion of the anterior leaflet that could cause SAM. Results: Of the 222 patients, 213 (95.9%) did not develop SAM while 9 (4.0%) patients developed SAM postoperatively. In the first group, 199 (89.6%) Patients with Respect Approach, 8 (4.0%) Patients had postoperative SAM. In the second group, 23 (10.4%) Patients with Resect Approach, 1 (4.4%) Patient hat postoperative SAM. (P-value 0.469). Of the 9 patients with SAM, the phenomenon was detected in 6 patients intraoperatively while in 3 patients, it was found postoperatively on the predischarge echocardiogram. Conclusion: There was no significant difference between both groups in the incidence of postoperative SAM. The length of the free edge of the anterior leaflet below the leaflet coaptation creates a “residual” anterior leaflet portion that plays an important role producing postoperative SAM phenomenon. By increasing the height of the leaflet coaptation, the length of the “residual” anterior leaflet portion can be reduced, which might help to reduce the risk of postoperative SAM phenomenon.

https://dgk.org/kongress_programme/jt2021/aP1488.html