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

BACKGROUND: Secondary subaortic stenosis (SSS) is a rare heart disease of the left ventricular outflow tract (LVOT). It usually occurs after cardiovascular correction with or without initial left ventricular outflow tract obstruction (LVOTO). Because most patients with SSS are asymptomatic, many do not realize the need for reoperation until the obstruction worsens. Few studies suggest the characteristics and reasons of SSS without initial SAS. We conducted a retrospective study to describe the characteristics and surgical outcomes of these patients. METHODS: In this study, we examined a single-center retrospective cohort of SSS patients without initial SAS undergoing resection from 2010 to 2019. Patients are defined as secondary subaortic obstruction requiring surgery after cardiovascular correction. Demographics, perioperative findings, and clinical data were analyzed. RESULTS: Twenty-three patients had undergone secondary cardiac surgery for SSS without initial SAS during 10 years in our center. The median age at operation was 7.3 (4.0-13.5) years. In this study, the most commonly associated cardiac lesions were ventricular septal defect (VSD), atrioventricular septal defect (AVSD), patent ductus arteriosus (PDA), and coarctation arch hypoplasia (COA). The surgical techniques included membranous resection of five patients, fibromuscular resection of 17 patients, and reconstruction of the intraventricular baffle of one patient. The results of surgery in these patients are satisfied. The average LVOT gradient at the last follow up was 14.9 (7.8-26.2) mmHg. There was no operative mortality. Two patients had postoperative complications. The median follow-up period was 2.9 (1.1-4.3) years with one late death. Two patients (8.7%) had recurrence of stenosis. CONCLUSIONS: Secondary subaortic stenosis is an uncommon heart disease. The reason is related to several causes, including missed diagnosis, unnoticed abnormalities of LVOT, and further changes of geometric morphology by intracardiac surgery. The results of surgery in these patients are satisfied. However, the recurrence of stenosis is still frequent.

Long-term follow-up of subvalvular aortic stenosis in children: a single-centre experience.

OBJECTIVE: The aim of this study is to evaluate clinical and surgical outcomes of children with subaortic stenosis, to determine the risk factors for surgery and reoperation and to compare isolated subaortic stenosis and those concomitant with CHDs. METHODS: The study involved 80 children with subaortic stenosis. The patients were first classified as isolated and CHD group, and the isolated group was further classified as membranous/fibromuscular group. The initial, pre-operative, post-operative and the most recent echocardiographic data, demographic properties and follow-up results of the groups were analysed and compared. The correlation of echocardiographic parameters with surgery and reoperation was evaluated. RESULTS: There was a significant male predominance in all groups. The frequency of the membranous type was higher than the fibromuscular type in the whole and the CHD group. The median time to the first operation was 4.6 years. Thirty-five (43.7%) patients underwent surgery, 5 of 35 (14%) patients required reoperation. The rate of surgery was similar between groups, but reoperation was significantly higher in the isolated group. The gradient was the most important factor for surgery and reoperation in both groups. In the isolated group besides gradient, mitral-aortic separation was the only echocardiographic parameter correlated with surgery and reoperation. CONCLUSION: Reoperation is higher in isolated subaortic stenosis but similar in membranous and fibromuscular types. Early surgery may be beneficial in preventing aortic insufficiency but does not affect the rate of reoperation. Higher initial gradients are associated with adverse outcomes, recurrence and reoperation.

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

BACKGROUND: Subaortic stenosis (SAS) was a rare congenital heart disease of left ventricular outflow tract (LVOT), ranging from "isolated" lesions to "tunnel" or "diffuse" lesions. We conducted a retrospective study to describe the characteristics of patients with different lesions and analyze the risk factors for reoperation. METHODS: In this study, we examined a single-center retrospective cohort of SAS patients undergoing resection from 2010 to 2019. Patients were classified as simple lesion group (n = 37) or complex lesion group (n = 28). Demographics, perioperative findings, and clinical data were analyzed. RESULTS: The surgical effect of the two groups was significantly lower than that before the operation (p < .05). The median age at operation was 6 (3-11.8) years. There was no operative mortality. In complex lesion group, cardiopulmonary bypass time (CPB time), aortic cross-clamping time (ACC time), mechanical ventilation time, and intensive care unit (ICU) stay time were longer. The median follow-up period was 2.8 years (range: 1-3.8), with two late death. Six patients (9.2%) required reoperation due to restenosis or severe aortic insufficiency. The freedom from reoperation rates at 5 years was 66.7% for simple lesion but only 52.3% for complex lesion (p = .036). CONCLUSIONS: Although the lesions include many forms, SAS resection was still satisfactory. However, the reoperation after initial surgical treatment was not infrequent, especially in patients with complex lesion.

Intraoperative transesophageal echocardiographic predictors of recurrent left ventricular outflow tract obstruction in children undergoing subaortic stenosis resection.

BACKGROUND: Intraoperative transesophageal echocardiography (iTEE) is used to assess for residual left ventricular outflow tract obstruction (LVOTO) after surgical resection of subaortic membrane causing subaortic stenosis (sub-AS). We aimed to identify the iTEE features associated with recurrence of LVOTO. METHODS: We conducted a retrospective study of children undergoing sub-AS resection from June 2006 to June 2014. Doppler assessment of the flow velocity and the anatomical features of the left ventricular outflow tract were analyzed from stored echocardiograms. Recurrent LVOTO was defined as an increase in the mean pressure gradient across the left ventricular outflow tract of > 15 mm Hg on the most recent follow-up echocardiogram from the mean pressure gradient on the predischarge echocardiogram or as doubling of the mean pressure gradient to a value ≥20 mm Hg. RESULTS: Thirty-five patients were included, with median age at surgery was 8.1 years (range: 0.7-29 years) and median follow-up was 47 months (2-91 months). Ten patients (29%) had recurrent LVOTO, which was associated with a shorter distance between the narrowest diameter of the outflow tract and the aortic valve on iTEE [median 0.59 cm (range 0.39-0.74) vs 0.98 cm (0.75-1.5), P = .03]. No patients with more than mild residual LVOTO on iTEE regressed to mild or no LVOTO on follow-up echocardiograms. CONCLUSIONS: LVOTO recurrence after sub-AS resection is common, and residual LVOTO remains the same or increases over time. Proximity of the LVOTO to the aortic valve is a risk factor for recurrent LVOTO. These findings may be useful in counseling patients and to guide the frequency of postoperative follow-up.

Severe Valvular Aortic Stenosis and Fixed Subvalvular Aortic Stenosis: A Rare and Challenging Combination.

A 58-year-old man with a history of hypertension presented with accelerating angina. Transthoracic echocardiography revealed a thickened aortic valve with pressure gradients and an estimated aortic valve area suggestive of mild aortic stenosis. Left heart catheterization demonstrated non-significant coronary artery disease. Pressure tracings showed a high left ventricular pressure and a mean gradient across the aortic valve of 69 mmHg. Subsequent transesophageal echocardiography revealed a subvalvular aortic stenosis that was secondary to the subaortic membrane, with severe valvular aortic stenosis. The patient underwent surgical resection of the subaortic membrane followed by bioprosthetic aortic valve replacement, with resolution of his symptoms. Video 1: Transesophageal echocardiography, five-chamber view, showing the calcified aortic valve and subaortic membrane. Video 2: Transesophageal echocardiography, long-axis view, showing aliasing of the aortic flow at valvular and subvalvular levels.

When Is It Better to Wait? Surgical Timing and Recurrence Risk for Children Undergoing Repair of Subaortic Stenosis.

Recurrence of subaortic stenosis (SAS) after surgery is common in children. The effects of patient characteristics and surgical timing on disease recurrence are largely unknown. We performed a retrospective study, assessing the relative effects of patient age and left ventricular outflow tract (LVOT) gradient on the need for reoperation for recurrent SAS. We included all children <20 years of age who underwent initial surgical resection of SAS at our center, January 2003-December 2013. Stratified logistic regression was performed, considering the effects of patient demographics, clinical characteristics, echocardiographic parameters, and operative technique, and clustering standard errors by surgeon. The multivariable model was used to simulate predicted probabilities of recurrent SAS for children at varying ages and baseline LVOT gradients. Sixty-three patients (38 males) underwent initial operation for SAS. Patients were followed for a median of 3.7 years (IQR 1.2-7.1). Twenty-one percent of patients (n = 13) underwent reoperation for SAS. Twelve were male. For every 10 mmHg increase in preoperative peak gradient in boys, the odds of reoperation for SAS doubled (OR 2.01, CI 1.5-2.72, p < 0.001), and for every additional 6 months of age, the odds of reoperation decreased by 14% (OR 0.86, CI 0.84-0.88, p < 0.001). Both younger age and higher preoperative outflow tract gradient are independently associated with risk of reoperation. Clinicians should consider the age and rate of LVOT gradient change-and not just the absolute gradient-in determining initial surgical timing.

Surgical strategies and outcomes of congenital supravalvular aortic stenosis.

BACKGROUND: Various surgical techniques have been introduced to treat supravalvular aortic stenosis (SVAS). However, there is no consensus upon the optimal approach. This study reviewed our institutional experience in the management of SVAS. METHODS: Ninety patients undergoing surgery for SVAS were identified between 2009 and 2016. Based on surgical techniques, patients were divided into three groups: McGoon repair (n = 63), Doty repair (n = 24), and Brom repair (n = 3). Median follow-up was 38.5 months (range, 4 months-7.5 years). Patient status, cumulative event-free survival rate, and risk factors for adverse clinical outcomes were assessed. RESULTS: The early mortality rate was 3.3%. There was one late death and two reinterventions. No differences were observed among three surgical groups. Event-free survival was 98.4% at 3 years and 96.5% at 5 years. Diffuse-type SVAS and a preoperative gradient greater than 60 mmHg were risk factors for adverse cardiac remodeling within 6 months post-surgery. Residual aortic stenosis was associated with male gender, preoperative aortic valve stenosis, and a preoperative peak gradient greater than 90 mmHg. Eleven patients (out of 30) who underwent concomitant pulmonary artery patching had a residual pulmonary gradient greater than 40 mmHg. CONCLUSIONS: Surgical repair of SVAS can be safely achieved using different techniques, with similar midterm mortality and reintervention rates. Higher preoperative gradient is associated with worse clinical results. Issues regarding surgical timing and concomitant pulmonary artery stenosis need to be further addressed.

[Right branch pulmonary artery stenosis with supravalvar aortic stenosis as a complication of Lecompte maneuver for tetralogy of Fallot associated with absent pulmonary valve].

The patient was diagnosed with tetralogy of Fallot associated with absent pulmonary valve syndrome and a low birth weight of 1,912 g. He suffered from respiratory distress on day 14 and received non-invasive positive pressure ventilation. At 5 months of age and 4.1 kg, he underwent intracardiac repair including right ventricular outflow repair with a monocusp patch, patch closure of the ventricular septum defect and right pulmonary transposition to the anterior of the ascending aorta following the Lecompte maneuver for airway decompression. He was subsequently discharged to home and exhibited an uneventful clinical course with non-invasive positive pressure ventilation for 5 months postoperatively. However, right pulmonary artery and supra-aortic stenosis was noted 2 years after the operation. Computed tomography (CT) and angiography showed ascending aorta strangulation by the right pulmonary artery with right ventricular outflow regurgitation. Right pulmonary artery reconstruction using polytetrafluoroethylene graft interposition and repeat right ventricular outflow repair with bicuspid hand-sewn valves was therefore performed;the postoperative course was uneventful. Pre- and post-operative management using non-invasive positive pressure ventilation and airway decompression with pulmonary artery translocation is a useful strategy in patients exhibiting symptomatic tetralogy of Fallot associated with absent pulmonary valve syndrome in the neonatal period.

Subvalvular Aortic Stenosis.

Obstruction of the left ventricular outflow tract (LVOT) occurs in six out of 10,000 live births. The obstruction occurs in the aortic valve level in 71 percent, in subvalvular level in 14 percent, and supravalvular level in 8 percent of cases. Subvalvular aortic stenosis (AS) can be either a fixed stenosis resulting from subaortic membrane or a dynamic stenosis because of hypertrophic cardiomyopathy. Here, we report a patient with subaortic membrane who became symptomatic in her sixth decade of life. Echocardiography is the preferred diagnostic modality. Indications for surgery include symptoms, LVOT gradient of 50 mmHg or more, and development of significant aortic regurgitation.

A modified technique of Konno aortoventriculoplasty for redo aortic valve replacement procedures.

This article puts forward a modified technique of Konno aortoventriculoplasty for repeat procedures. After incision of the ventricular septum, this approach involves aortic valve replacement using a mechanical valved conduit, reimplantation of the coronary arteries, and graft replacement of the ascending aorta. This modification allows the removal of the diseased ascending aortic wall caused by a previous patch enlargement or poststenotic dilation.

Congenital discrete subaortic stenosis in pregnancy: case report and literature review.

Today's growing numbers of pregnant patients with congenital heart defects presents challenges for cardiologists treating adult patients. The case is presented of a 19-year-old woman who was admitted with a threatened miscarriage in the third trimester and was diagnosed with an incomplete atrioventricular canal, cleft mitral valve with severe regurgitation, and severe congenital subaortic stenosis caused by a subaortic membrane. She was managed conservatively, delivered via cesarean section, and then underwent surgical repair of all defects with good outcome. Here, a review is provided of the literature on the natural course, complications, and treatment strategies of subaortic stenosis, together with a summary of recommendations for the management of the condition.

Evaluation of subvalvular aortic stenosis in children: a 16-year single-center experience.

Subvalvular aortic stenosis accounts for 1-2 % of all congenital heart disease and for 8-20 % of cases of left-ventricular outflow tract (LVOT) obstruction in children. Recurrence of subaortic stenosis (SAS) is not uncommon after surgical management. This study was performed to investigate the clinical and surgical outcomes and to estimate the predictability of recurrences of SAS. Seventy-nine patients age 3-21 years with SAS between 1994 and 2010 were reviewed. Fifty-one patients had discrete SAS, whereas the remaining 15 patients had fibromuscular ridge-type SAS. Mean follow-up time without surgery was 22 months (range of 1-94). Forty-one patients with a diagnosis of SAS underwent surgery. Recurrence rates were 22.7 % (15 patients), and these patients developed SAS at a mean of 4.7 years follow-up. We performed second surgical membrane resection in only 1 patient. The risk of recurrence of SAS was only linked to higher preoperative LVOT gradient. Twenty-three patients had no aortic regurgitation (AR) at preoperative echocardiography. Of these, 39.1 % had trivial, 8.7 % had mild, and 8.7 % had moderate AR after surgery; there was no significant AR. We conclude that surgical intervention was required most of the time in patients with SAS, and surgical outcomes was excellent even if there were associated cardiac defects. The risk of recurrences was higher, especially in patients with higher initial LVOT gradients, although a second surgery was rarely necessary in these patients.

Surgery for congenital aortic stenosis in children with left ventricular noncompaction.

Left ventricular noncompaction (LVNC) is an uncommon genetic disorder of endocardial morphogenesis, which carries a high mortality from heart failure or sudden cardiac death. This condition is often first diagnosed in adults, but it has also been described in children with other cardiac anomalies. We discuss the management of a 10-year-old female with congenital aortic stenosis associated with LVNC.

Surgical management of supravalvar aortic stenosis with coronary artery involvement.

Supravalvar aortic stenosis is characterized by an obstruction of the left ventricular outflow tract distal to the aortic valve. Its association with left main coronary artery stenosis is well known but right coronary artery involvement has not been reported. We describe two cases of supravalvar aortic stenosis with coronary artery stenosis and its surgical management.

[Epidemiological, clinical and echographic profile of patients operated for subvalvular aortic stenosis in the region of Sfax (Tunisia) and factors associated with postoperative recurrence: an observational study]. / Profil épidémiologique, clinique et échographique des patients opérés pour un rétrécissement aortique sous-valvulaire dans la région de Sfax (Tunisie) et facteurs associés à la récidive post-opératoire: étude observationnelle.

Subvalvular aortic stenosis is difficult to manage due to the evolutionary unpredictability of stenosis and a high recurrence rate after surgical treatment. The purpose of this study is to describe the profile of patients undergoing surgery for the treatment of aortic subvalvular stenosis and to investigate factors associated with post-operative recurrence of the subaortic obstacle. We conducted an observational study of all patients operated for subvalvular aortic stenosis, whose data were collected in the Department of Cardiology of the Sfax University Hospital between January 2010 and December 2020. The study involved 28 patients, with predominance of male sex (64.29%, n=18). At diagnosis, the mean age was 6.82 (±4.84) years and 19 patients (67.85%) had symptoms. On echocardiography, maximal subaortic gradient ≥50 mmHg was found in 23 patients (82.14%). Cardiovascular malformations associated with subvalvular stenosis were found in 16 patients (57.14%). The average age of patients at the time of surgery was 10.43 (±7.08) years. Subaortic membrane resection was the most commonly used technique (46.4%, n=13). It was associated with septal myomectomy in 8 patients (28.6%). Postoperative mortality rate was zero. Residual gradient ≥30 mmHg was reported in 8 patients (28.6%) after surgery. Recurrences were observed in 7 patients (25%) of whom 6 underwent reintervention. In multivariate analysis, only postoperative residual gradient was significantly associated with recurrence (p=0.030, OR=33.785, 95% CI: 1.398-816.754). Despite old age at diagnosis and surgery, favorable short-term outcomes were reported, but recurrences were frequent in the long term. This highlights the role of regular, perioperative and postoperative, clinical and echographic monitoring of these patients.

Correlates and causes of death in patients with severe symptomatic aortic stenosis who are not eligible to participate in a clinical trial of transcatheter aortic valve implantation.

BACKGROUND: Transcatheter aortic valve implantation is currently being evaluated in patients with severe aortic stenosis who are considered high-risk surgical candidates. This study aimed to detect incidences, causes, and correlates of mortality in patients ineligible to participate in transcatheter aortic valve implantation studies. METHODS AND RESULTS: From April 2007 to July 2009, a cohort of 362 patients with severe aortic stenosis were screened and did not meet the inclusion/exclusion criteria necessary to participate in a transcatheter aortic valve implantation trial. These patients were classified into 2 groups: group 1 (medical): 274 (75.7%): 97 (35.4%) treated medically and 177 (64.6%) treated with balloon aortic valvuloplasty; and group 2 (surgical): 88 (24.3%). The medical/balloon aortic valvuloplasty group had significantly higher clinical risk compared with the surgical group, with significantly higher Society of Thoracic Surgeons score (12.8±7.0 versus 8.5±5.1; P<0.001) and logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) (42.4±22.8 versus 24.4±18.1; P<0.001). The medical/balloon aortic valvuloplasty group had a higher New York Heart Association functional class, incidence of renal failure, and lower ejection fraction. During median follow-up of 377.5 days, mortality in the medical/balloon aortic valvuloplasty group was 102 (37.2%), and during median follow-up of 386 days, mortality in the surgical group was 19 (21.5%). Multivariable adjustment analysis identified renal failure (hazard ratio [HR]: 5.60), New York Heart Association class IV (HR: 5.88), and aortic systolic pressure (HR: 0.99) as independent correlates for mortality in the medical group, whereas renal failure (HR: 7.45), Society of Thoracic Surgeons score (STS; HR: 1.09) and logistic EuroSCORE (HR: 1.45) were correlates of mortality in the in the surgical group. CONCLUSIONS: Patients with severe symptomatic aortic stenosis not included in transcatheter aortic valve implantation trials do poorly and have extremely high mortality rates, especially in nonsurgical groups, and loss of quality of life in surgical groups.

The dilemma of subaortic stenosis--a single center experience of 15 years with a review of the literature.

OBJECTIVE: The term "subaortic stenosis" includes a variety of obstructions of the left ventricular outflow tract (LVOT), ranging from a short (discrete) subvalvular membrane to long, tunnel-like narrowing. An association with other congenital lesions is frequent. We reviewed the reported literature and describe our results, analyzing the nomenclature of and risk factors for restenosis after surgical treatment. METHODS: From 1994 to 2009, 81 children (53 males, 28 females; median age: 57 months, range [ R]: 5-204) underwent surgical relief of a subaortic stenosis. Patients were divided, according to pathology, into short segment (group A, n = 42) and complex obstructions (group B, n = 39), with the latter including long segment stenosis and/or associated anomalies such as aortic coarctation, interrupted aortic arch or Shone's complex. RESULTS: Surgery resulted in a significant reduction of the gradient between the left ventricle and the aorta in both groups (Δ P group A: 51 ± 28 mmHg, group B: 46 ± 25 mmHg). There was no operative mortality. One patient died in the early postoperative period due to pericardial tamponade. Median follow-up was 90 months (R = 0.5-187). Twenty-five (31%) patients required reoperation because of recurrent stenosis after a median of 43 months (R = 0.5-128). Seven (16%) patients belonging to group A developed restenosis, and 18 (46%) in group B. Freedom from reoperation for all patients was 60% after 10 years. 10 (40%) of the patients of group B were ultimately treated with a Ross-Konno reconstruction of the LVOT. CONCLUSION: Despite adequate surgical resection, recurrence of subaortic stenosis within several years after initial surgical treatment is frequent, especially in patients with complex lesions. In cases requiring reoperation, the surgical therapy is often extensive, and even includes Ross-Konno reconstruction of the LVOT.

Staged surgical approach in neonates with a functionally single ventricle and arch obstruction: pulmonary artery banding and aortic arch reconstruction before placement of a bidirectional cavopulmonary shunt in infants.

The success rate of right-heart bypass surgery in patients with a functionally single ventricle (f-SV) and systemic obstruction is low. In patients with a high risk of subaortic stenosis, we performed an initial step of pulmonary artery banding (PAB) and arch reconstruction before placing a bidirectional cavopulmonary shunt (BCPS) in infants with or without Damus-Kaye-Stansel (DKS) anastomosis. We assessed the success of right-heart bypass surgery. Between October 2003 and August 2008, we performed surgery in 19 neonates (median age 5 days) with f-SV and arch obstruction. Extended aortic arch anastomosis, with or without distal arch augmentation, was performed in 10 patients, and subclavian flap aortoplasty was performed in 9 patients. The circumference of the PAB was determined as the individual patient's body weight in kilograms plus 16.2 +/- 3.7 mm. Eighteen of 19 infants (95%) underwent successful BCPS placement at a median age of 7.8 months. DKS anastomosis was performed concomitantly during BCPS placement in 11 infants in whom subaortic stenosis was morphologically suspected but not demonstrated physiologically. As our first-stage operation, arch reconstruction plus PAB provided high success rates for right-heart bypass operations. This strategy is not leading, but it is a reliable approach for progression along a Fontan pathway.

Palliative combined cutting and high-pressure balloon valvuloplasty in six dogs with severe, symptomatic subaortic stenosis.

INTRODUCTION/OBJECTIVES: Severe subaortic stenosis (SAS) is a congenital heart defect in dogs that often results in clinical signs and reduced survival. The objective of this study was to describe characteristics of dogs with severe, symptomatic SAS who underwent combined cutting and high-pressure balloon valvuloplasty (CB/HPBV). ANIMALS, MATERIALS, AND METHODS: Retrospective description of the clinical characteristics, CB/HPBV procedural deviations from reported methodology and outcomes in a series of six client-owned dogs with severe, symptomatic SAS. RESULTS: Breeds included two each of Newfoundland, Golden retriever, and German shepherd. Median age was 10.1 months (range: 5-72.3 months), and median weight was 25.5 kg (range: 21.8-36.4 kg). Before CB/HPBV, clinical signs were present in all dogs; four were managed for congestive heart failure (CHF). Three dogs had concurrent congenital heart disease. Median Doppler-estimated left ventricular outflow tract pressure gradient was pre-operatively 149.7 mmHg (range: 89.9-254.7 mmHg) and post-operatively 134.1 mmHg (range: 83.9-181.2 mmHg). Median aortoseptal angle was steep at 136° (range: 109-143°). Clinical improvement was documented in all dogs, based on temporary discontinuation of diuretics and/or owner-perceived reduction in clinical signs. At the time of writing, three dogs had died suddenly, one was euthanized because of recurrence of clinical signs, and one died in CHF. Median survival time was 26.4 months after procedure (range: 6.3-45.8 months). One dog remained alive at 44 months after procedure. CONCLUSIONS: Palliative CB/HPBV is a potential therapeutic option for dogs with severe, symptomatic SAS complicated by concurrent congenital heart disease, arrhythmias, or CHF.