Surgical treatment results of secondary tunnel‐like subaortic stenosis after congenital heart disease operations: A 7‐year, single‐center experience in 25 patients

Abstract

Objective: To summarize the surgical results of secondary tunnel-like subaortic stenosis (STSS) after congenital heart disease (CHD) operations, the pathogenesis of STSS is analyzed and its operative effect and prognosis are evaluated. Methods: We analyzed clinical data from 25 patients who underwent surgical repair for STSS in Fuwai Hospital from 1 January 2009 to 31 December 2015. There were 17 males and 8 females. The types of CHD included a double outlet right ventricle (DORV), a ventricular septal defect (VSD), and partial atrioventricular septal defects (PAVSDs). The median age of the patients at the time of their first CHD operation was 1 year (1 month to 42 years). The median age of the patients at the time of STSS repair was 5 years and 8 months (2 years and 10 months to 48 years). The surgical types included the modified Konno procedure, Konno procedure, fibromuscular resection (FMR), and removal and reconstruction of the intraventricular baffle (RRIB).Results: All patients successfully received STSS repair. There were no surgical deaths in this study. The preoperative gradient across the left ventricular outflow tract was 81 (43-159) mm Hg, and the postoperative gradient was 8.2 (4-46.2) mm Hg. On the basis of the surgical techniques used for subaortic stenosis repair, we divided the patients into three subgroups: the Konno group (n = 11), the FMR group (n = 11), and the RRIB group (n = 3). Preoperatively, there was no significant difference in the gradient between the Konno group and the FMR group (ΔP, P = .287), but the Konno group was significantly better than the FMR group postoperatively (ΔP, P = .022). There were no significant statistical differences between the RRIB group and the other two groups in all these data. A third-degree atrioventricular block occurred in two patients after the operation, and both patients required a permanent pacemaker. All patients were followed up after discharge for a median duration of 5 years (3-9 years). During the follow-up period, none of the patients had any clinical symptoms or subaortic restenosis, and there was no late death.Abbreviations: ASO, arterial switch operation; AV, aortic valve; CHD, congenital heart disease; COA, coarctation of the aorta; DORV, double outlet right ventricle; FMR, fibromuscular resection; PAVSD, partial atrioventricular septal defect; PDA, patent ductus arteriosus; SSS, secondary subaortic stenosis; STSS, secondary tunnel-like subaortic stenosis; TOF, Tetralogy of Fallot; VSD, ventricular septal defect; ΔP, left ventricle-to-aorta peak pressure gradient.

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

“…Also, left ventricular remodeling is known to be associated with poor prognosis after surgery [6]. Surgical therapy for SAS consists of correction of the obstruction, which may involve simple membrane removal, extensive ring resection with or without myectomy, or a Konno procedure [7][8][9]. The timing of the surgery varies, with recommendations ranging from early operation to longer periods of observation depending on the patient's characteristics.…”

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

“…For the DORV, the decrease in the effective VSD size, turbulent flow, and the sinuous shape of the tunnelization caused subaortic septal or conal muscle hypertrophy or fibrous tissue deposits. 16 Under this circumstance, extended septoplasty was a safe and effective method for the treatment of SAS as Fibro-Muscular Resection. 17 Aortic regurgitation, as the most dreaded sequelae of SAS, appears to be at increased risk, and was also the main risk of reoperation 18,19 This study showed that 61 (93.8%) patients had tri-leaflet valves, and 34 (51.5%) patients had aortic regurgitation before surgery.…”

“…Our study showed that one patient with DORV underwent extended septoplasty. For the DORV, the decrease in the effective VSD size, turbulent flow, and the sinuous shape of the tunnelization caused subaortic septal or conal muscle hypertrophy or fibrous tissue deposits 16 . Under this circumstance, extended septoplasty was a safe and effective method for the treatment of SAS as Fibro‐Muscular Resection 17 …”

Surgical Repair of Secondary Subaortic Stenosis in Congenital Heart Disease Without Initial Subaortic Obstruction

“…SSS also is an iatrogenic disease after biventricular repair of DORV. SSS after biventricular repair of DORV may develop in 3.5-5.5% of cases [Zhang 2020]. The changes in geometric morphology, such as the decrease in the effective VSD size, turbulent flow, and the sinuous shape of the tunnelization, caused subaortic septal or conal muscle hypertrophy or fibrous tissue deposits [Zhang 2020; Kim 2010].…”

“…SSS after biventricular repair of DORV may develop in 3.5-5.5% of cases [Zhang 2020]. The changes in geometric morphology, such as the decrease in the effective VSD size, turbulent flow, and the sinuous shape of the tunnelization, caused subaortic septal or conal muscle hypertrophy or fibrous tissue deposits [Zhang 2020; Kim 2010]. The turning radius of the intraventricular tunnel is the main factor, affecting the pressure difference.…”