In this article, we present a case of a hypertrophic septum with the systolic anterior motion (SAM) of the mitral valve successfully treated with aortotomy, wedge resection of the interventricular septum, mitral valve repair.

Preparations for the operation were made and the patient underwent an operation where the aortic two-stage venous cannulation was done. After giving a cardioplegic solution in the fashion of antegrade and retrograde, cardiac arrest was achieved and, then, aortotomy was done. Exploration of the septum and mitral valve was done via the aortic orifice. The septum was found to be thickened. Anterior chordae were elongated, leading to SAM of the mitral valve (Figure 1). Septal myectomy was done by resecting a piece of about 8 mm from the septum, while the anterior leaflet was plicated by 6.0 polypropylene suture through the aortic valve. The suture line was along the clear zone of the mitral anterior leaflet. We resected the secondary chordae that tightened the anterior leaflet. Intraoperative transesophageal echocardiography was used to evaluate valves, SAM of the mitral valve, and LVOT gradient. There were no severe LVOT gradient. The mitral valve was perfectly coaptating and no SAM or mild degree regurgitation was found in the mitral leaflet.

Figure 1: (a) Hypertrophic septum. (b) Anterior mitral leaflet.

Postoperatively, the patient was followed for one day in the intensive care unit and was, then, transferred to the ward. Control echocardiography showed 1^st-2^nd degree mitral insufficiency without SAM, and the aortic gradient decreased to 57/23 mmHg. The patient became free from previous complaints. On postoperative Day 8, the patient was discharged and scheduled for follow-up in the outpatient setting. Unfortunately, after about 18 months of the operation, he was found to have 3^rd to 4^th degree mitral regurgitation and is symptom-free with medical treatment.

On other hand, the residual leaflet elongation is found to be more likely in patients with SAM of the mitral valve than non-SAM patients. The long posterior leaflet of the mitral valve is considered a strong risk factor for SAM, while the anterior papillary muscle displacement has been identified as a risk factor, as well.[5] In our case, we found that there were secondary chordae of the mitral valve holding the anterior leaflet tightly and long anterior chordae. We resected the secondary chordae and plicated the long anterior charge after septal myectomy.

After mitral repair for mitral valve regurgitation, there is always a possibility of developing regurgitation again or an increase in the degree of regurgitation. In a study conducted by Flameng et al.,[6] even after highly successful repair, the recurrence of mitral valve regurgitation possibility increased over time and occurred at a constant rate, mainly in degenerative valves.[6] In our case, the patient had 3rd to 4th degree mitral regurgitation after about 18 months of surgery, which was 1^st to 2^nd degree immediately after the operation.

The patient developed mitral regurgitation again after about 18 months. He is still on medication; however, he may need reoperation for valve replacement in the future. In general, repairing the mitral valve apparatus is done through a left atriotomy or, in small left atrium cases, the approach can be achieved via the interatrial septum after right atriotomy.[7] In the cases where aortotomy is done, some prefer performing mitral apparatus repair via aortotomy, particularly when it is associated with septal myectomy.[8] In our case, we preferred performing mitral valve chordae repair via aortotomy and aortic orifice and, the left atrium incision was avoided.

In conclusion, septal wedge myectomy with anterior mitral chordae plication can be done with satisfying results in HOCM associated with SAM cases. However, the possibility of recurrent mitral valve regurgitation over time should be kept in mind.

Declaration of conflicting interests
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Funding
The authors received no financial support for the research and/or authorship of this article.

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