Enlargement of left ventricular outflow tract using an autologous pericardial patch for anterior mitral valve leaflet and septal myectomy through trans‐mitral approach for the treatment of hypertrophic obstructive cardiomyopathy.

Objective: Modified Morrow procedure is the gold standard of surgical intervention for hypertrophic obstructive cardiomyopathy (HOCM). However, there are certain cases without complete relief of obstruction through trans‐aortic approach, we, therefore, described an unusual technique. We aimed to retrospectively analyze this series of patients to reveal its safety and efficiency. Methods: We retrospectively analyzed a total of 247 consecutive HOCM patients in our center from January 2016 to December 2019. Sixteen of them who underwent enlargement of left ventricular outflow tract (LVOT) using an autologous pericardial patch for anterior mitral valve leaflet and septal myectomy through trans‐mitral approach were recruited in this study. Baseline characteristics, perioperative data, and the outcomes were studied. Results: Of the 16 patients, there was no operative mortality. No permanent pacemaker implantation and ventricular septal defects formation were observed. The peak pressure gradient of LVOT decreased from 97.56 ± 23.81 mmHg to 7.56 ± 2.13 mmHg (p <.01) after operation and 10.19 ± 2.93 mmHg (p <.01) 3 months later. The average septal thickness decreased from 18.38 ± 3.56 mm to 10.00 ± 2.74 mm (p <.01). During a mean follow‐up of 34.25 ± 12.85 months (range, 15–57), no patient required cardiac reoperation. At the last follow up, the mean peak pressure gradient of LVOT was 10.12 ± 2.03 mmHg and no patient had more than moderate mitral regurgitation. Conclusion: Enlargement of LVOT using an autologous pericardial patch for anterior mitral valve leaflet and septal myectomy through trans‐mitral approach is feasible and reliable for the treatment of certain types of HOCM cases. [ABSTRACT FROM AUTHOR]