Surgical repair of subaortic stenosis resection: 10 years of single-center experience in 65 patients

The prognostic significance of early troponin levels in patients undergoing aortic ridge surgery

Subaortic stenosis is a CHD that can lead to left ventricular hypertrophy, heart failure, and aortic valve damage if left untreated. The gold standard treatment for subaortic stenosis is septal myectomy. However, there is no clear consensus on the surgical margins required for adequate muscle resection. In this retrospective study, we reviewed the records of 83 patients who underwent subaortic stenosis surgery between 2012 and 2020 to investigate the effect of early troponin levels on prognosis. We excluded patients with additional cardiac pathologies, hypertrophic obstructive cardiomyopathy, and valvular aortic stenosis.Troponin levels were recorded in the early post-operative period, and patients were monitored for complications such as ventricular arrhythmia, left ventricular systolic dysfunction, infective endocarditis, and pacemaker implantation. The troponin levels were significantly higher in the patients who had septal myectomy. The degree of myectomy affected the risk of complications in the early post-operative period and recurrence in the later period. However, when the gradient was substantially or completely removed by myectomy, patients experienced significant symptom improvement in the early post-operative period, and their late survival was equivalent to that of healthy individuals of the same age.Our findings suggest that monitoring troponin levels in patients undergoing septal myectomy may be beneficial in predicting the risk of complications. However, further studies are needed to establish the optimal surgical technique and extent of muscle resection required for subaortic stenosis treatment. Our study adds to the existing knowledge of the benefits and risks associated with septal myectomy as a treatment option for subaortic stenosis.

Adult Presentation of Subaortic Stenosis with Subaortic Membrane Treated with Surgical Removal

Subaortic stenosis (SAS) is a rare heart disease in adults with an unclear etiology and variable clinical presentation. In some cases, SAS appears as hypertrophic cardiomyopathy with obstruction due to the accompanying systolic anterior motion of the mitral valve. A 46-year-old male with dizziness for several months presented in the outpatient department. Two-dimensional transthoracic echocardiography demonstrated a slightly hypertrophic left ventricle with normal systolic function without wall-motion abnormalities. Just below the aortic valve, a linear structure protruding from the septum side and the left-ventricular outflow tract (LVOT) side of the mitral valve was confirmed, which was causing a significant pressure gradient (mean and maximum of 91 mmHg and 138 mmHg, respectively). A diagnosis of SAS with subaortic membrane was made, and surgical myomectomy and subaortic membrane removal surgery were performed. Postoperative transthoracic echocardiography did not show flow acceleration through the LVOT, nor a significant pressure gradient across the aortic valve. This case report highlights the clinical significance of SAS with subaortic membrane, which can be confused with aortic stenosis of other etiology.

Adult Presentation of Subaortic Stenosis with Subaortic Membrane Treated with Surgical Removal

Subaortic stenosis (SAS) is a rare heart disease in adults with an unclear etiology and variable clinical presentation. In some cases, SAS appears as hypertrophic cardiomyopathy with obstruction due to the accompanying systolic anterior motion of the mitral valve. A 46-year-old male with dizziness for several months presented in the outpatient department. Two-dimensional transthoracic echocardiography demonstrated a slightly hypertrophic left ventricle with normal systolic function without wall-motion abnormalities. Just below the aortic valve, a linear structure protruding from the septum side and the left-ventricular outflow tract (LVOT) side of the mitral valve was confirmed, which was causing a significant pressure gradient (mean and maximum of 91 mmHg and 138 mmHg, respectively). A diagnosis of SAS with subaortic membrane was made, and surgical myomectomy and subaortic membrane removal surgery were performed. Postoperative transthoracic echocardiography did not show flow acceleration through the LVOT, nor a significant pressure gradient across the aortic valve. This case report highlights the clinical significance of SAS with subaortic membrane, which can be confused with aortic stenosis of other etiology.