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.

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.

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.

Comparison of the cardiac output and stroke volume response to upright exercise in children with valvular and subvalvular aortic stenosis.

Cardiac output and stroke volume were evaluated in 17 children (mean age 11.5 +/- 3 years) with discrete, membranous subvalvular (Group I, n = 7) and valvular (Group II, n = 10) aortic stenosis during submaximal and maximal (greater than 75% predicted maximal oxygen consumption) upright cycle ergometry. Patients with valvular aortic stenosis were further subdivided on the basis of their aortic valve gradient at rest determined by cardiac catheterization (Group IIA, gradient less than 40 mm Hg; Group IIB, gradient greater than or equal to 40 mm Hg). These patients were matched with 17 control subjects on the basis of age, sex, height and intensity of exercise during maximal exertion. Cardiac and stroke indexes were determined by the acetylene rebreathing method at each exercise level. Stroke volume index in Group I was significantly greater at rest when compared with that in control subjects (69 +/- 13 versus 53 +/- 11 ml/m2, alpha = 0.01, p less than 0.05) and that in patients in Group II (69 +/- 13 versus 47 +/- 12 ml/m2, alpha = 0.01, p less than 0.05). Patients with subvalvular aortic stenosis were unable to increase their stroke volume index from rest to submaximal exercise and also decreased their stroke volume index at maximal exercise levels. In contrast, patients with mild valvular aortic stenosis (Group IIA) displayed a normal exercise response. Patients with severe valvular aortic stenosis (Group IIB) had a blunted stroke volume response at rest and at each level of exercise, as well as signs of myocardial ischemia (ST segment depression) during maximal exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Malaligned outlet septum with subpulmonary ventricular septal defect and abnormal ventriculoarterial connection: a morphologic spectrum defined echocardiographically.

A retrospective analysis of 62 echocardiograms from 22 patients with malaligned outlet septum, subpulmonary ventricular septal defect and abnormal ventriculoarterial (VA) connection was performed and the results were confirmed by intraoperative inspection, cardiac catheterization and angiography, or pathologic specimen analysis in 21 of the 22 patients. The purpose of this study was to determine the relative incidence of the primary morphologic features; the correlation between the presence or absence of mitral valve to pulmonary valve fibrous continuity and the type of VA connection; the types and incidence of additional cardiovascular anomalies; and the correlation between the determination of the VA connection by echocardiography versus that ascertained at intraoperative and autopsy inspection. A spectrum of VA connections was found, ranging from double outlet right ventricle (23%) at one extreme, through an intermediate type (64%) in which the pulmonary artery was overriding the ventricular septum, thereby having no consistent and predominant connection to either ventricle, to a discordant VA connection (13%) at the opposite end of the spectrum. All three types of VA connection occurred whether or not there was mitral valve to pulmonary valve fibrous continuity. Additional cardiovascular anomalies were present in 95% of patients, the most common being aortic arch obstructive lesions in 59%, anomalous attachments of the atrioventricular valve tension apparatus in 55% and subaortic stenosis in 50%. A method of echocardiographic determination of the VA connection that correlated with that determined intraoperatively and from pathologic specimen analysis is described.

Subaortic obstruction in complex congenital heart disease: management by proximal pulmonary artery to ascending aorta end to side anastomosis.

Six patients with univentricular heart and one patient with d-transposition of the great arteries had transection of the main pulmonary artery with an end to side anastomosis of the main pulmonary artery to the ascending aorta to relieve subaortic obstruction. Two operations were performed as a palliative procedure within the first 6 months of life and five were performed as part of a definitive repair (four modified Fontan procedures and one repair of transposition of the great arteries with ventricular septal defect). There was one surgical death (14%) occurring 1 day postoperatively from low cardiac output. The remaining six patients are doing well 1 to 19 months postoperatively (mean 11.4 months). The proximal pulmonary artery to ascending aorta end to side anastomosis is an effective means of bypassing subaortic obstruction associated with complex congenital heart disease.

Subaortic membrane in an adult patient with coronary artery disease.

A case of subaortic membrane with coronary artery disease in a 48-year-old man is described. He was referred to our hospital for cardiac murmur, which was discovered on routine clinical examination. He had no significant past medical history apart from dizziness while exercising. Subaortic membrane was totally excised; left internal thoracic artery was anastomosed to left anterior descending artery by end-to-side technique. The postoperative 2-year course of the patient was uneventful.

Fixed subaortic stenosis in the young: medical and surgical course in 83 patients.

Eighty-three patients aged 11 months to 25 years were followed up a median of 6.1 years (range 8 days to 24 years) after diagnosis of fixed subaortic stenosis (SAS). Fourteen (17%) had significant noncardiac defects and 47 (57%) had additional cardiac malformations. The left ventricular (LV) outflow gradient increased in 25 of 26 patients catheterized more than once before surgery. Of 15 patients less than 12 years old with gradients less than or equal to 40 mm Hg, 10 ultimately underwent operation after developing severe obstruction; another has progressed to a gradient of 45 mm Hg at 6 years of age. Before surgery (at a median age of 12 years), 55% had aortic regurgitation (AR), which was usually mild. Infective endocarditis occurred in 12% of the group, with a frequency of 14.3 cases per 1,000 patient-years. Seventy-four patients were operated on, with 6 early (8%) and 7 late (9%) deaths. Twelve underwent reoperation to relieve residual obstruction. Surgery reduced gradients in patients with discrete SAS from 83 +/- 33 to 29 +/- 30 mm Hg, but in 6 patients with tunnel SAS the reduction was less satisfactory. AR was absent or mild in most patients postoperatively. When the gradient was reduced to less than 80 mm Hg, infective endocarditis did not occur unless there were other residual lesions. These data suggest that it is reasonable to resect discrete SAS in children less than 10 to 12 years old with LV outflow gradients greater than or equal to 30 mm Hg.

Use of three-dimensional echocardiography for analysis of outflow obstruction in congenital heart disease.

To evaluate the feasibility and accuracy of 3-dimensional (3D) echocardiography in analysis of left and right ventricular outflow tract (LVOT and RVOT) obstruction, 3D echocardiography was performed in 28 patients (age 4 months to 36 years) with outflow tract pathology. Type of lesion and relation to valves were assessed. Length and degree of obstruction were measured. Three-D data sets were adequate for reconstruction in 25 of 28 patients; 47 reconstructions were made. In 13 patients with LVOT obstruction, 3D echocardiography was used to study subvalvular details in 8, valvular in 13, and supravalvular in 1. Four of these 13 patients had complex subaortic obstruction. In 12 patients with RVOT lesions, 3D echocardiography was used to study subvalvular details in 11, valvular in 12, and supravalvular in 2. Three-dimensional reconstructions were suitable for analysis in 100% of subvalvular LVOT, 77% valvular LVOT, 100% supravalvular LVOT, 100% subvalvular RVOT, 50% valvular RVOT, and 50% supravalvular RVOT. Twenty patients underwent operation, and surgical findings served as morphologic control for thirty-four 3D reconstructions (LVOT 17, RVOT 17). Operative findings revealed an accuracy at subvalvular LVOT of 100%, valvular LVOT 90%, supravalvular LVOT 100%, subvalvular RVOT 100%, valvular RVOT 100%, and supravalvular RVOT 100%. Quantitative measurements could adequately be performed. Three-D echocardiography is feasible and accurate for analyzing both outflow tracts of the heart. Particularly, generation of nonconventional horizontal cross sections allows a good definition of extension and severity of lesions.

Discrete subvalvular aortic stenosis. An evaluation of operative therapy.

Angiocardiographic and operative observations support the validity of classifying the spectrum of congenital subvalvular aortic stenosis into a membrane, fibromuscular collar, and tunnel. Our current operative method is to excise a thin membrane or thick fibrous ridge, and, if a fibromuscular collar or tunnel is identified, to effect a left ventricular myomectomy as described by Morrow for hypertrophic subaortic stenosis. Data from experience with 35 children indicate that this approach is effective and safe. Gradients are substantially reduced and residual obstruction acceptable. Successive clinical evaluations (100 percent of 33 survivors) over an interval of 1 to 13 years (mean of 6) affirm that amelioration of the obstruction endures.

Supernumerary mitral valve producing subaortic stenosis.

A ten-year-old girl with severe subaortic stenosis was found to have relatively mature valvular endocardial cushion tissue (fibromyxomatous sheets with a chorda tendinea attached to a left ventricular papillary muscle) immediately beneath the aortic valve. This structure behaved like a valve mechanism, obstructing the left ventricular outflow tract during ventricular systole. This anomaly is an extreme on the spectrum of obstructive endocardial cushion malformations.

Aortoventriculoplasty with the pulmonary autograft: the "Ross-Konno" procedure.

BACKGROUND: For patients with complex left ventricular outflow tract obstruction, including hypoplastic aortic anulus with or without severe diffuse subaortic stenosis, various aortoventriculoplasty procedures (e.g., Konno procedure and its modifications; extended aortic allograft root replacement) are important management options. In younger patients, however, reoperation for valve replacement is inevitably required, and anticoagulation issues pose additional problems. The pulmonary autograft provides a promising option for aortic valve replacement as part of the aortoventriculoplasty procedure in children. Long-term follow up shows that the pulmonary autograft functions well as the systemic arterial (neoaortic) valve and that valve growth occurs. METHODS: Between July 1993 and May 1995, 11 patients 4 days to 17 years old (median 12 months) underwent aortoventriculoplasty with pulmonary autograft (Ross-Konno procedure). The diagnoses were aortic stenosis with or without subaortic stenosis (n = 8), Shone complex (n = 2), and interrupted aortic arch with subaortic stenosis (n = 1). On average, 1.9 previous interventions had been performed per patient, including a previous Konno procedure in one patient. The aortic root was replaced with a pulmonary autograft valve. The left ventricular outflow tract was enlarged with a Dacron polyester fabric patch in two patients, with an allograft aortic patch in two patients and a right ventricular infundibular free wall muscular extension harvested in continuity with the autograft in seven patients. RESULTS: Intraoperative transesophageal echocardiographic assessment revealed mild aortic insufficiency in one patient. One patient had a residual left ventricular outflow tract gradient of 15 mm Hg. Significant complications were cardiac tamponade from bleeding (n = 1) and complete heart block necessitating a permanent pacemaker (n = 1). Follow-up ranged from 2 weeks to 16 months. To date, there have been no late deaths or reoperations. Follow-up echocardiography revealed mild autograft insufficiency in one patient and a 16 mm Hg residual left ventricular outflow tract gradient in one patient. CONCLUSIONS: Initial experience suggests that aortoventriculoplasty with the pulmonary autograft is an excellent alternative for young patients with complex left ventricular outflow tract obstruction. Because the pulmonary autograft has been shown to grow after implantation, reoperation on the left ventricular outflow tract is likely to be avoided.

Management of infants with left ventricular outflow obstruction by conduit interposition between the ventricular apex and thoracic aorta.

On the basis of experience with older children, creation of a double-outlet ventricle by interposition of a valved conduit between the apex of the left ventricle and the thoracic aorta appeared to be an option for treating life-threatening left ventricular outflow tract obstruction even in the small heart of the infant. Over the recent 3 year period, nine infants ranging in age from 3 days to 13 months with various forms of left ventricular outflow tract obstruction underwent placement of an apical-aortic conduit to decompress the hypertensive left ventricle. There were two early and two late deaths. Five patients are clinically well and developing normally 5 to 23 months following the operation. This series demonstrates that this operation permits normal growth and development in infants previously failing to thrive. Echocardiographic and cardiac catheterization data suggest that left ventricular function need not be adversely affected by placement of a stent in the small infant ventricle; rather, ventricular function can be markedly improved. Although the mortality in this series is appreciable, it appears that apical-aortic conduit interposition can provide significant palliation for infants with otherwise lethal left ventricular outflow tract obstruction.

Angiocardiography in congenital subvalvular aortic stenosis: prognosis and operative indications.

Twenty-three patients with congenital subvalvular aortic stenosis are reviewed. The importance of classifying this stenosis into four types based on angiocardiographic findings is stressed, as are the indications for left heart catheterization during the preoperative and postoperative course of the disease. The type of congenital subvalvular aortic stenosis should be an important consideration during the discussion of operative indications in both asymptomatic and symptomatic patients.

Critical subaortic stenosis in a newborn caused by accessory mitral valve tissue.

A 2-week-old newborn girl underwent successful surgery in our clinic for critical subaortic stenosis caused by accessory mitral valve tissue, which, because of excessive growth, protruded into the left ventricular outflow tract. The preoperative pressure gradient below the aortic valve was 80 mm Hg. The operation consisted of resection of the accessory tissue through a combined aortotomy and atriotomy approach without residual pressure gradient and mitral valve incompetence. This approach is recommended to ensure that accessory tissue is removed without damaging the mitral valve.

Aortic/mitral obstruction and coarctation of the aorta.

The prevalence, anatomy and physiology, clinical manifestations, laboratory findings, and management of patients with aortic/mitral obstruction and coarctation of the aorta are assessed. Subaortic stenosis reviewed includes discreet membranous and tunnel subaortic stenosis as well as hypertrophic obstructive cardiomyopathy. The discussion of valvular aortic stenosis includes both congenital and acquired forms of the disease. Supravalvular aortic stenosis is described along with coarctation of the aorta. Mitral valvular stenosis includes the congenital as well as acquired variety with focus on the congenital lesion. Current opinion regarding the medical, the cardiac catheterization, interventional, and the surgical approaches to therapy is presented.

The progressive nature of subaortic stenosis in congenital heart disease.

Data derived from serial hemodynamic and angiocardiographic investigations on pediatric patients not subjected to intervening intracardiac operations support the view that subaortic stenosis in congenital heart disease tends to be a progressive disorder. Our data are obtained from two groups of patients. The first comprised 22 patients with discrete subaortic stenosis in relative isolation. The second was made up of 19 patients with the fibrous or fibromuscular forms of discrete subaortic stenosis associated with a perimembranous ventricular septal defect. The results from both groups support our initial contention. The progressive character of subaortic stenosis in these two situations illustrates the dynamic nature of congenital heart disease, and the tendency of a changing form and function.

Fixed subaortic stenosis with congenital aneurysm of sinus of Valsalva--cross-sectional and Doppler echocardiographic diagnosis of a rare association.

A 13-year-old girl was diagnosed by cross-sectional and Doppler echocardiography to have the rare combination of congenital aneurysm of the right sinus of Valsalva rupturing into the right ventricular outflow tract and a discrete subaortic fibrous shelf with severe subvalvar stenosis, moderate aortic regurgitation and left ventricular dysfunction. The findings were confirmed at cardiac catheterisation and surgery.

Obstruction of the left ventricular outflow tract: anatomical observations and surgical implications.

Obstruction within the outflow tract from the left ventricle can take several anatomic forms. To understand better these substrates, we reviewed the anatomy in the normal heart and, with this background, focused on the malformations observed at each level of the outflow tract which produce stenosis. We examined 75 malformed hearts and reviewed the literature pertinent to surgical aspects of obstruction. Close study of the normal aortic valve shows the lack of any discrete fibrous structure which can be described in terms of a ring-like annulus. The semilunar attachment of the leaflets makes a crown-shaped arrangement at the ventriculo-arterial junction rather than a strict ring. In the pathological study, valvar abnormalities were found in 45 cases. The valve had three leaflets in 20 cases, two leaflets in 24 cases and one leaflet in to the other. In two cases, additional obstruction was found at the sinutubular junction. Subvalvar stenosis was found in 30 hearts, the aortic valve being trifoliate in 28 and bifoliate in 2. The main substrate of subvalvar obstruction was posterior malalignament of the outlet septum (40%), followed by muscular septal hypertrophy (23%); obstruction was also an intrinsic feature in association with atrioventricular septal defects (14%). Although rare in our material, it can also be due to a fibrous or fibromuscular shelf. In our review of the literature, we have highlighted the various forms of valvar malformation and commented on the surgical options. Clear analysis of both the level of obstruction, and its precise anatomic substrate are essential for optimal surgical intervention.