Transaortic mitral valve secondary chordal cutting in patients with obstructive hypertrophic cardiomyopathy and mild septal hypertrophy

Abstract

A proportion of patients with obstructive hypertrophic cardiomyopathy (HCM) and severe heart failure symptoms have only mild septal hypertrophy (1). In such patients, mitral valve (MV) abnormalities play an important role in systolic MV leaflets displacement into the left ventricular LV outflow tract and blood flow obstruction (1-3). Therefore, conventional septal myectomy alone may not be sufficient to relieve LV obstruction and symptoms, and often MV repair or replacement is the surgical alternative (1). Transaortic cutting of MV secondary chordae is a novel technique for MV repair that, associated with a shallow septal myectomy, abolishes the outflow gradient, relieves heart failure symptoms, and avoids MV replacement in patients with obstructive HCM and mild septal thickness (4).A 45-year-old female patient with obstructive HCM, mild septal hypertrophy and severe heart failure symptoms (New York Heart Association functional class III) unresponsive to medications was referred to our institution for surgical treatment of LV outflow obstruction. Physical examination revealed blood pressure 124/72 mmHg and heart rate of 72 BPM on bisoprolol 10 mg/day. Transthoracic echocardiography showed mild septal hypertrophy (17 mm) confined mainly to the basal and medium portion of the anterior septum, with marked systolic anterior motion of the MV leaflets and leaflet-septal contact at rest, and moderate left atrial dilatation. Doppler echocardiography showed an LV outflow maximal gradient of 72 mmHg under basal conditions, moderate-to-severe MV regurgitation, and a systolic pulmonary pressure of 32 mmHg. Cardiac magnetic resonance documented a small area of intramural delayed enhancement on the anterior septum. Coronary angiography was normal. Because of severe outflow gradient and heart failure symptoms, relatively mild septal thickness, MV leaflets with anterior leaflet tenting, and important MV regurgitation, we planned a shallow surgical myectomy, possibly associated with MV secondary chordal cutting through a median sternotomy. Surgical technique PreparationAfter induction of general anaesthesia, intra-operative transesophageal echocardiography (TEE) is performed to assess magnitude and distribution of septal hypertrophy, and carefully inspect the MV features and morphology and function of the MV apparatus. The heart is then arrested and protected by infusion of anterograde warm blood cardioplegia into the aortic root. During the first dose of cardioplegia, 1 mg/kg of esmolol is injected into the reservoir of the extracorporeal circulation system. Additional doses of cardioplegia are administered into the right and left coronary ostia every 20 minutes. Starting from the second cardioplegia, the dosage of esmolol is decreased to 0.5 mg/kg. OperationSeptal myectomy is performed through an aortotomy, Ann Cardiothorac Surg 2017;6(4):426-428 www.annalscts.com as previously reported (5). In particular, to allow better exposure of the ventricular septum during myectomy, a double transverse stitch is positioned in correspond...

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

“…Although there are many different surgical approaches and methods, the modified Morrow procedure through trans-aortic approach is still considered as the gold standard surgical treatment, showing a verified surgical result and good remission of symptoms for a long time. 8,9,11 The trans-mitral approach was first described in 1963 by Lillehei and Levy. 10 They chose this approach for HOCM patients just because of suboptimal exposure through the traditional trans-aortic approach.…”

“…As we all know, a satisfactory procedure for HOCM consists of three major goals: completely thickened septal muscle resection, dealing with the anterior mitral valve leaflet to avoid postoperative SAM, and release of abnormal papillary muscle and chordae attachments. 8,9,[11][12][13] Compared with the traditional trans-aortic approach via the aortic incision, the trans-mitral approach via the base of the anterior mitral leaflet provided a more clear panoramic exposure of the interventricular septum, making myectomy easily and avoiding heart block, 14,15 through this approach, experienced surgeons could even identify the pale fibrous hinges subaortic hit caused by SAM. [16][17][18] Also, this approach provided a wide vision of the anterior papillary muscles and its base.…”

Enlargement Of Left Ventricular Outflow Tract Using An Autologous Pericardial Patch For The Anterior Mitral Valve Leaflet And Septal Myectomy Through Trans-mitral Approach For The Treatment Of Hypertrophic Obstructive Cardiomyopathy

“…Although there are many different surgical approaches and methods, the modi ed Morrow procedure through trans-aortic approach is still considered as the gold standard surgical treatment, showing a veri ed surgical result and good remission of symptoms for a long time [8,9,11]. The trans-mitral approach was rstly described in 1963 by Lillehei and Levy [10].…”

“…They chose this approach for HOCM patients just because of suboptimal exposure through the traditional trans-aortic approach. As we all know, a satisfactory procedure for HOCM consists of three major goals: completely thickened septal muscle resection, dealing with the anterior mitral valve lea et in avoid of postoperative SAM, and release of abnormal papillary muscle and chordae attachments [8,9,11,12,13]. Compared with the traditional trans-aortic approach via the aortic incision, the trans-mitral approach via the base of the anterior mitral lea et provided a more clear panoramic exposure of the interventricular septum, making myectomy easily and avoiding heart block [14,15], through this approach, experienced surgeons could even identify the pale brous hinges subaortic hit caused by SAM [16,17,18].…”

“…For a long time, modi ed Morrow procedure has been the gold standard of surgical treatment, which was performed through the trans-aortic approach. In fact, in addition to modi ed Morrow operation through the transaortic approach, there are other approaches, including tans-apical and trans-mitral approach [9,10,11,12,13]. In clinical practice, we found many special cases, such as the aortic valve annulus is very small, the angle between the aortic valve annulus and the mitral valve annulus is less than 120 degrees, the anterior mitral lea et is too long, etc.…”