Late survival and freedom from cardiac events are excellent after SVR, also when concomitant MVCAD requires complete revascularization. Ventricular arrhythmias and impaired left ventricular anterior wall function are predictors of worse outcome.
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...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.