[Discrete Subaortic Stenosis in an Adult; Report of a Case].

Discrete subaortic stenosis (DSS) is a well-described cause of isolated left ventricular outflow tract obstruction( LVOTO) in children. But prevalence, rate of progression and postoperative data in adults are limited. We report a case of a 30-year-old woman, who was referred to our institution because of chest pain and loss of consciousness. Echocardiography revealed DSS with LVOTO (peak gradient 81 mmHg) and mild aortic regurgitation. Increased age at the time of diagnosis, female sex and preoperative left ventricular outflow tract(LVOT) gradient ≥80 mmHg were thought to be predictors for reoperation, therefore the obstructing membrane was circumferentially excised and concomitant localized myectomy of the ventricular septum was performed to achieve complete relief of the LVOT obstruction. Her postoperative course was uneventful, and she was discharged on the 5th postoperative day.

Natural history of discrete subaortic stenosisin adults: a multicentre study.

AIMS: Discrete subaortic stenosis (DSS) is often diagnosed early in life and known for its sometimes rapid haemodynamic progression in childhood and strong association with aortic regurgitation (AR). However, data about the evolution of DSS in adulthood are scarce. Therefore, we aimed to evaluate the natural history of DSS, and identify risk factors for the progression of DSS, AR, and intervention-free survival. METHODS AND RESULTS: Conservatively managed adult DSS patients were included in this retrospective multicentre cohort study. Mixed-effects and joint models were used to assess the progression of DSS and AR, and intervention-free survival. Longitudinal natural history data were available for 149 patients [age 20 (IQR: 18-34) years, 48% male]. Sixty patients (40.3%) had associated congenital heart defects (CHDs). The median follow-up duration was 6.3 (IQR: 3.0-12.4) years. The baseline peak left ventricular outflow tract (LVOT) gradient was 32.3 ± 17.0 mmHg and increased by 0.8 ± 0.1 mmHg/year. While the baseline LVOT gradient (P = 0.891) or age (P = 0.421) did not influence the progression rate, the presence of associated CHD was associated with faster progression (P = 0.005). Mild AR was common (58%), but did not significantly progress over time (P = 0.701). The median intervention-free survival was 16 years and associated with the baseline LVOT gradient [hazard ratio (HR) = 3.9 (95% CI: 2.0-7.6)], DSS progression [HR = 2.6 (95% CI: 2.0-3.5)], and AR [HR = 6.4 (95% CI 2.6-15.6)]. CONCLUSION: In contrast to children, DSS progresses slowly in adulthood. In particular, patients with associated CHD are at risk for faster progression and should be monitored cautiously. Discrete subaortic stenosis progression is not influenced by the baseline LVOT gradient or age. Mild AR is common, but non-progressive over time.

Anomalous muscle band resulting in severe subaortic stenosis in an adult.

Abnormalities of the mitral valve are uncommon causes of subaortic stenosis. This paper describes an anomalous muscle band of the mitral valve causing severe subaortic stenosis.

Subaortic stenosis associated with systolic anterior motion.

Left ventricular outflow tract obstruction in children is classified according to the site of the obstruction into a supra-aortic type, valvular type, and subaortic type (subaortic stenosis). Subaortic stenosis, in turn, is classified into two major subtypes, i.e., a discrete type, which accounts for most cases and a tunnel type, and one minor subtype, the accessory mitral tissue type, which is rare. Systolic anterior motion (SAM) is a phenomenon that is commonly observed in hypertrophic cardiomyopathy. We report a rare case of subaortic stenosis associated with SAM, which was caused by cleft anterior mitral leaflet and an accessory papillary muscle. Surgical treatment was successful, and there were no complications.

Acquired discrete subaortic stenosis late after mitral valve replacement.

Although acquired left ventricular outflow obstruction has been reported in a variety of conditions, there are scant reports of its occurrence following mitral valve replacement (MVR). This study describes two female patients, who developed severe discrete subaortic stenosis, five years following MVR. In both cases, the mitral valve was replaced by a porcine Carpentier-Edwards 27-mm bioprosthesis with preservation of mitral valve leaflets. The risk of very late left ventricular outflow tract obstruction after bio-prosthetic MVR with preservation of subvalvular apparatus needs to be kept in mind in symptomatic patients.

Congenital coronary artery anomaly simulating a ventricular septal defect.

Anomalous origin of the circumflex artery of the right sinus of Valsalva is a rare finding which may be present with other cardiac malformations. A 19-year-old man presented with syncope. A transthoracic echocardiogram revealed discrete subaortic stenosis with a small defect just below the aortic valve, suggesting a ventricular septal defect. Transesophageal echocardiography showed anomalous origin of the circumflex artery from the right sinus of Valsalva. This was confirmed by coronary angiography. The patient underwent successful web resection without concomitant coronary surgery. Failure to demonstrate a coronary artery anomaly can be misleading for surgeons and perilous for patients.

Balloon dilation of discrete subaortic stenosis associated with other cardiac defects in children.

Balloon dilation (BD) is reported as an effective treatment for isolated discrete thin membranous subaortic stenosis (SAS). We asked if BD of SAS with associated cardiac defects: 1) is effective; 2) creates or worsens mitral insufficiency in the presence of valvar membrane attachment; and 3) creates or worsens aortic insufficiency. BD was performed on 13 patients (9 females, 4 males with a mean age of 5.8 years and an age range of 1-14 years old) for SAS with the following associated defects: VSD (6 patients), coarctation (4 patients), complete atrioventricular canal (1 patient), tetralogy of Fallot (1 patient), and abnormal mitral valve (4 patient). Prior intracardiac surgical procedures (3 for SAS resection) had been performed in 46% of the study group. Peak gradient was reduced from 53 +/- 40 mmHg to 31 +/- 25 mmHg (p < 0.01). The resulting gradient was related to the predilation gradient (r = 0.71; p =.006). Thin membranes (< 3 mm) were associated with lower initial gradient (p < 0.02), lower resulting gradient (p < 0.001) and a greater percent gradient reduction (76% versus 36%; p < 0.01). Aortic insufficiency, which was present predilation in 77%, did not change and was not created in any patient. Mitral valve membrane attachment was present in 69% and associated with a lower resulting gradient (p < 0.006). Mitral insufficiency was not created in 10 patients, was unchanged in 2 and was improved in 1 patient. Surgical procedures were ultimately required in 8 patients during follow-up. BD of SAS associated with other cardiac defects achieves the following: 1) reduces SAS gradient in selected patients without creating or worsening aortic insufficiency; 2) does not create or worsen mitral insufficiency when mitral valve membrane attachment is present; 3) improves preoperative hemodynamics; and 4) is unlikely to be effective in post-surgical recurrence.

[The role of transesophageal echocardiography (TEE) in assessment of left ventricular tract obstruction]. / Rola echokardiografii przezprzelykowej (TEE) w diagnostyce podzastawkowego zwezenia aorty.

Twelve children with subaortic stenosis were analysed. Nine of them developed left ventricular outflow obstruction after surgery for congenital heart disease (VSD + IAA, VSD + DORV, VSD + TGA, VSD + CoA) and then developed an isolated form of primary stenosis. Both echocardiographic exams, TTE and TEE were performed in all patients. TTE was sufficient to assess isolated subaortic stenosis. In children after cardiosurgery, TEE was more reliable and provided more detailed visualisation of the stenosis and its relationship to surrounding structures.

Fixed subaortic stenosis: a clinical dilemma for clinicians and patients.

Subaortic stenosis carries considerable morbidity and mortality. In most cases, patients have an underlying left ventricular outflow tract morphology that promotes turbulence at the outflow tract, which induces the development of subaortic fibromuscular tissue. A subset of patients will progress to develop severe stenosis and aortic regurgitation, but it has been difficult to determine which patients are at risk. While resection of the subaortic tissue improves immediate outcome, many patients have recurrence of both stenosis and regurgitation, questioning the efficacy of surgical intervention in asymptomatic patients. This review article describes the current understanding of the etiology, treatment, and prognosis of subaortic stenosis.

Discrete subaortic stenosis 37 years after repair of a ventricular septal defect.

Discrete subaortic stenosis (DSS) is uncommon in adults after surgical correction of congenital heart defects. There are only a few published reports on the occurrence of DSS in adults. We present an adult case with DSS after repair of a ventricular septal defect (VSD). The case was a 44-year old female patient who underwent VSD closure at 7 years of age. Thirty-seven years later, she presented with congestive heart failure associated with severe subaortic membranous stenosis and atrial fibrillation (AF) that required surgical repair. We report successful surgical treatment of this adult patient with DSS and AF 37 years after repair of a VSD.

Progressive discrete subaortic stenosis developed after successful primary repair of the supravalvular aortic stenosis in Williams syndrome.

Discrete subaortic stenosis is a rare, late complication of the surgical repair of congenital heart defects. Secondary subaortic stenosis late after surgical repair of supravalvular aortic stenosis in Williams syndrome has not previously been described. A 20 year-old female patient with Williams syndrome became symptomatic eight years after subaortic membrane resection. A discrete subaortic stenosis was identified by echocardiography. She was indicated for a Konno operation with a 19-mm Sorin SL valve inserted in the aortic position, along with ventricular septal defect closure with a pericardial patch. She produced a transient slight hypocalcemia after the operation. She was discharged home in a good condition on the fourth post-operative day. Intracardiac morphological and hemodynamic factors have been suggested as responsible for such a late complication. Our case study suggests the need for regular follow-up in patients with Williams syndrome, even after primary surgical repair.

Steepened aortoseptal angle may be a risk factor for discrete subaortic stenosis in adults.

Discussion exists whether discrete subaortic stenosis (DSS) is a congenital or acquired cardiac defect. Currently, it is regarded an "acquired" cardiac defect presumably secondary to altered flow patterns due to morphological abnormalities in the left ventricular outflow tract, as have been shown by some studies in the pediatric population. In this report, we demonstrated a steepened aortoseptal angle in adults with DSS without previous cardiac surgery in comparison to controls. Our results strengthen the hypothesis that altered flow patterns due to a steepened aortoseptal angle are a substrate for development of DSS in adults.

Subaortic stenosis produced by an accessory mitral valve: the role of echocardiography.

Subaortic stenosis caused by an accessory mitral valve is an exceedingly rare finding. We report the case of an asymptomatic 14-year-old patient, in whom transthoracic echocardiography revealed an accessory mitral valve in the left ventricular outflow tract, producing mild subaortic stenosis. Except for an aneurysm of the interventricular septum, with no shunt, there were no other anomalies. Transesophageal echocardiography provided details about the morphology and location of the accessory valve. Being asymptomatic and having only a mild gradient, antibiotic prophylaxis for infective endocarditis and follow-up were recommended. After 2 years the patient is asymptomatic, with a similar echocardiographic gradient.

Rheology of discrete subaortic stenosis.

The discrete form of subaortic stenosis is thought to be an acquired lesion, the aetiology of which may be a combination of factors which include an underlying genetic predisposition, turbulence in the left ventricular outflow tract, and various geometric and anatomical variations of the left ventricular outflow tract. A review of hypotheses relating to its aetiology is provided

Palliated congenital heart disease.

The group of patients with palliated complex forms of congenital heart disease presents a challenging and difficult management problem during the adolescent years. In patients not considered to be candidates for more fully palliated procedures that separate the circulations, a bidirectional caval pulmonary shunt, often associated with a systemic to pulmonary shunt, may provide significant palliation for several more decades. However, there remain a significant number of patients who, after some years, may develop increasing problems associated with myocardial failure and the development of serious atrial arrhythmias. Interventional cardiac catheterization combined with newer surgical techniques may return many of these patients to more satisfactory hemodynamic states. However, some patients during their adolescent years may eventually require cardiac transplantation for the long-term management of their complex congenital cardiac defects.

Accelerated ventricular rhythm in children: a review and report of a case with congenital heart disease.

We report a child with accelerated ventricular rhythm (AVR) and congenital heart disease. Three children with congenital heart defect associated with AVR were previously reported, but in each AVR occurred only postoperatively. Because our patient's 24-hour electrocardiograph recording showed AVR rates, and differences between sinus and AVR rates, exceeding published childhood limits, we reviewed the topic. On the basis of our review, we suggest guidelines for diagnosing AVR and differentiating it from ventricular tachycardia.