Discrete Subaortic Stenosis: Surgical Outcomes and Follow-Up Results in Infancy and hildhood, MOHAMED MAHMOUD ABDULLAH, TAREK SALAH, YASSER M. MENAISSY, HESHAM A. SHAWKY and MOHAMED A. KHALIL
Abstract
Background: The term "subaortic stenosis" (SAS) includes a variety of obstructions of the left ventricular outflow tract (LVOT), ranging from a short (discrete) subvalvular membrane to long, tunnel-like narrowing. Uncertainties remain regarding recurrence of subaortic obstruction and development of aortic insufficiency after repair.
Objectives: To assess the immediate, short and mid-term outcome of surgical intervention for SAS in terms of safety, efficacy in eliminating symptoms and gradients and prevention of disease progression.
Patients and Methods: In this cohort study, a total of 41 patients underwent surgical interventions for SAS. All patients were below 12 years of age. The patients were operated upon in Cairo University Hospitals, from April 2014 to February 2016. Pre-operative, operative and postoperative data were collected and analyzed statistically in the immediate postop-erative period, at 6 months and one year after surgery.
Results: Mean age of all patients was 5.5±3.4 years. Seventy five percent (75.6%) were males. All the patients were symptomatic. Preoperative mean pressure gradient (PG) was 74.6±20mmHg. Mean septal wall thickness (SWT) was 0.81±0.25cm. Immediate postoperative assessment showed significant clinical improvement and significant reduction of PG to 13.5±12.6mmHg, SWT to 0.3±1.1cm. Short-term and mid-term follow-up showed sustained improvement. There were no deaths.
Conclusion: The surgical treatment for SAS (resection of subaortic membrane and added myotomy or myectomy in selected patients) is generally safe and effective for clinical improvement and for reduction of the LVOT gradient and its consequences like AR. with a very low postoperative mortality and morbidity, early surgical intervention is recommended to preserve the aortic valve functions and to prevent further progression of the disease. However, progression of the aortic valve disease or even appearance of new regurgitation is possible; due to the persistent abnormal flow patterns in the subaortic region, even after good surgical resection. So, longer follow up periods are required to detect any late development of postoperative AR which may indicate another intervention.