[Minimally invasive right infra-axillary thoracotomy for transaortic modified Morrow procedure: a series of 60 cases]

Objective: To examine the short-term curative effect with minimally invasive right infra-axillary thoracotomy for transaortic modified Morrow procedure. Methods: The clinical data of 60 patients who underwent video-assisted thoracoscopic transaortic modified Morrow procedure from August 2021 to August 2022 at Department of Cardiovascular Surgery, Zhejiang Provincial People's Hospital were retrospectively analyzed. There were 31 males and 29 females, with the age (M (IQR)) of 54.0(22.3) years (range: 15 to 71 years). The echocardiography confirmed the diagnosis of moderate mitral regurgitation in 30 patients, and severe mitral regurgitation in 13 patients. Systolic anterior motion (SAM) was present preoperatively in 54 patients. All 60 patients underwent transaortic modified Morrow procedure through a right infra-axillary thoracotomy using femorofemoral cardiopulmonary bypass. Surgical procedures mainly included transverse aortic incision, exposure of left ventricular outflow tract (LVOT), septal myectomy, and correction of the abnormal mitral valve and subvalvular structures. Results: All 60 patients underwent the programmatic procedures successfully without conversion to full sternotomy. The cardiopulmonary bypass time was (142.0±32.1) minutes (range: 89 to 240 minutes), while the cross-clamp time was (95.0±23.5) minutes (range: 50 to 162 minutes). The patients had a postoperative peak LVOT gradient of 7.0 (5.0) mmHg (range: 0 to 38 mmHg) (1 mmHg=0.133 kPa). A total of 57 patients were extubated on the operating table. The drainage volume in the first 24 h was (175.9±57.0) ml (range: 60 to 327 ml). The length of intensive care unit stay was 21.0 (5.8)h (range: 8 to 120 h) and postoperative hospital stay was 8 (5) days (range: 5 to 19 days). The postoperative septal thickness was 11 (2) mm (range: 8 to 14 mm). All patients had no iatrogenic ventricular septal perforation or postoperative residual SAM. The patients were followed up for 4 (9) months (range: 1 to 15 months), and none of them needed cardiac surgery again due to valve dysfunction or increased peak LVOT gradient during follow-up. Conclusion: Using a video-assisted thoracoscopic transaortic modified Morrow procedure through a right infra-axillary minithoracotomy can provide good visualization of the LVOT and hypertrophic ventricular septum, ensure optimal exposure of the mitral valve in the presence of complex mitral subvalvular structures, so that allows satisfactory short-term surgical results.