[Transesophageal echocardiography assessment of mitral valve for patients with atrial septal defects undergoing surgical repair].

Objectives: To investigate the application of transesophageal echocar-diography assessment for mitral valve in patients with atrial septal defects undergoing repair surgery.

Methods: The study group comprised of thirty-two adult patients with atrial septal defect who underwent thoracoscopic repair surgery at the First Affiliated Hospital of the Air Force Medical University from March to September 2022. Two-dimensional and real-time three-dimensional transesophageal ultrasonography of the mitral valve were performed after anesthesia. The parameters of the mitral valve structure at the late diastolic and late systolic stages were recorded, including anteroposterior and left-right annular diameters, anterior and posterior valves lengths, the vertical distance from the coaptation point of leaflet zone 2 during systole to the annular plane (mitral valve coaptation depth) and mitral valve coaptation length. Data from 32 patients with normal intracardiac structure and no mitral valve regurgitation (control group) were also collected and compared with those of the study group. Concurrent mitral valvoplasty was performed during the atrial septal defect repair surgery for 7 patients with significant mitral valve structural abnormalities and 2 patients with significantly increased mitral regurgitation after cardiac resuscitation. The study group was followed up with transthoracic echocardiography for 2 years postoperatively.

Results: In the study group, 26 (81.3%) patients had varying degrees of mitral valve morphological abnormalities. Among them, 10 (31.3%) patients had short mitral valve coaptation length or depth, 12 (37.5%) patients had closure point malposition, and 4 (12.5%) patients had different bulge of anterior and posterior leaflets. Compared with the control group, the study group had significantly smaller systolic and diastolic mitral left-right annular diameter, mitral posterior valves lengths, mitral coaptation length or depth (all P<0.05), a higher pulmonary systemic flow ratio (P<0.01), and a lower maximum blood flow velocity across the mitral valve (P<0.05). After 2 years of follow-up, among the 9 patients who underwent concurrent mitral valvoplasty, the mitral valve maintained no or little regurgitation, and the average mitral valve pressure difference was less than 5 mmHg (1 mmHg=0.133 kPa). Among the 23 patients without concurrent mitral valvoplasty, 2 patients had moderate regurgitation 1 year after surgery, with a pulmonary/systemic flow ratio larger than 2.8.

Conclusions: Patients with large atrial septal defects often have abnormal mitral valve structure. Therefore transesophageal echocardiography is recommended for mitral valve assessment during the surgery. If significant mitral valve structural abnormalities are detected, concurrent mitral valvoplasty is recommended.