Long-Term Aortic Valve Function in Patients With or Without Surgical Treatment for Discrete Subaortic Stenosis.

The purpose of this study was to evaluate the long-term function of the aortic valve in patients with discrete subaortic stenosis (DSS), and its prognostic implications. 34 patients with the diagnosis of isolated DSS were treated at our pediatric heart center between 1992 and 2019. Demographic, echocardiographic and surgical data were analyzed. 26 patients had surgery to remove the subaortic membrane. The primary endpoint of this study was a change in the aortic valve function, secondary outcomes included functional class, aortic valve replacement, and reoperation due to recurrence of DSS. The mean post-operative follow-up time was 7.07 years (1-22.5). At the time of the most recent follow up, in the surgical group 11 patients (46%) had echocardiographic evidence of deterioration in their aortic valve insufficiency (AI) (p < 0.002). The deterioration was associated with a pre-operative left ventricular outflow tract (LVOT) gradient greater than 49 mmHg (p < 0.022). 8 patients with DSS were followed for a mean of 12.9 years (6.8-21.3), without meeting the criteria for surgical intervention, none showed any change in the aortic valve function during follow-up time. DSS resection may not prevent worsening of aortic valve insufficiency over time. Patients with stable AI and low LVOT gradient may not require surgery. Given these findings, it may be appropriate to carefully follow patients with new onset AI and low LVOT gradient, delaying surgical intervention.

Membranous subaortic stenosis coexisting with hypertrophic cardiomyopathy: A case report.

Subaortic stenosis (SAS) is a congenital heart disease, and its association with hypertrophic cardiomyopathy is very rare and clinically underappreciated. We report here a case of a 45-year-old female who was admitted to our hospital with chest tightness and shortness of breath. Both transthoracic and transesophageal echocardiography revealed asymmetric left ventricular hypertrophy and a membrane-like echo below the level of the aortic valve. This patient was diagnosed with membranous SAS with hypertrophic cardiomyopathy. Screening of her immediate family members revealed that her son also had hypertrophic cardiomyopathy. The patient chose conservative treatments and has been closely followed-up after discharge.

Resection of subaortic membrane for discrete subaortic stenosis.

BACKGROUND: We reviewed the long-term results of surgery for discrete subaortic membrane (SubAM) from a single institute. METHODS: A retrospective review of medical records of all patients (n = 146) who underwent resection of a SubAM for discrete subaortic stenosis between 1990 and 2015 at the All India Institute of Medical Sciences, New Delhi, India was undertaken. RESULTS: Median age at surgery was 9.0 years (9 months-47 years). There was one early death. Preoperative peak left ventricular outflow tract (LVOT) Doppler gradient was 83.4 ± 26.2 mmHg (range: 34-169 mmHg). On preoperative echocardiography, aortic regurgitation (AR) was absent in 69 (47.3%), mild in 35 (24%), moderate in 30 (20.5%), and severe in 12 (8.2%). After surgery, the LVOT gradient was reduced to 15.1 ± 6.2 mmHg (P < 0.001). Fourteen patients (9.6%) who had residual/recurrent significant gradients are currently being followed-up or awaiting surgery. There was improvement in AR for operated patients with freedom from AR of 92.6 ± 0.03% at 15 years. Kaplan-Meier survival at 25 years was 93.0 ± 3.9% (95% confidence interval: 79.6, 97.7). Freedom from re-operation at 25 years was 96.9 ± 1.8%. CONCLUSIONS: Long-term results of surgery for discrete SubAM are good. Resection of the membrane along with septal myectomy decreases the risk of recurrence.

Subaortic stenosis surgical correction after previous substernum coloesophagoplasty.

Alternate approaches for aortic valve procedures are rare but occasionally used in cardiac surgery because of previous mediastinum radiotherapy or other procedures that preclude median sternotomy. We present one case of right lateral thoracotomy for membrane subaortic stenosis resection in a child with a restrosternal gastric tube.

Illustration of the echocardiographic diagnosis of subaortic membrane stenosis in adults: surgical and live three-dimensional transoesophageal findings.

We report here two cases of patients admitted in our institution for heart failure. The first had been previously diagnosed with severe aortic valve stenosis and was referred for aortic valve replacement. The myocardial and valvular anatomy combined with the Doppler profiles allowed, however, to suggest the diagnosis of a discrete subaortic membrane that was confirmed by surgical findings. In the second case, the use of real-time three-dimensional transoesophageal echocardiography (3D TEE) provided superb 3D visualization quality of the subaortic membrane and allowed assessing the stenosis area using the multiplanar review mode. Hence, the use of live real-time 3D TEE is likely to be key in the spatial assessment of this complex lesion.

The role of shear stress in the pathogenesis of discrete subaortic stenosis: implications for surgical treatment.

Discrete subaortic stenosis (DSS) is characterized by the presence of an obstructing membrane in the left ventricular outflow tract (LVOT). Evidence suggests that the formation of DSS represents a fibroproliferative reaction of the endocardium occurring in response to alterations in shear stress caused by geometric abnormalities within the LVOT. The aim of this review is to discuss the role of altered LVOT shear stress in the pathogenesis of DSS, and its implications in surgical decision making.

Noninvasive evaluation of membranous subaortic stenosis: complimentary roles of echocardiography and computed tomographic angiography.

A 29-year-old Ethiopian woman that was referred to the Wisconsin Heart Hospital for treatment of subaortic stenosis, diagnosed 4 years earlier, in Ethiopia, using transthoracic echocardiography. Preoperative evaluation included transesophageal echocardiography, which showed severe membranous subaortic stenosis with a mean outflow gradient of 70 mmHg. Cardiac computed tomographic angiography also demonstrated a subaortic membrane, and additionally showed normal epicardial coronary arteries. The patient underwent uneventful surgical resection of the subaortic membrane without undergoing cardiac catheterization.

Takedown of Yasui procedure due to closed ventricular septal defect.

A two and a half year old girl who had undergone the Yasui procedure as a neonate for ventricular septal defect, subaortic stenosis, and interrupted aortic arch underwent follow-up catheterization 2 years postoperatively. It showed that the neo-left ventricular tract reconstructed by Damus-Kaye-Stansel anastomosis had occluded due to closure of the ventricular septal defect and residual subaortic stenosis at the original left ventricular outflow tract. The patient therefore underwent takedown of the Yasui procedure.

Left Ventricle to Right Atrial Shunt Associated With Ventricular-Atrial Malalignment, Double Outlet Right Atrium, and Subaortic Membrane.

We describe an asymptomatic 7-year-old boy who was taken to the operating room for repair of a subaortic membrane and possible Gerbode's defect. He was found to have a double outlet right atrium associated with an accessory atrioventricular valve in addition to a small atrial septal defect and subaortic membrane. Regurgitant flow through this accessory valve led to the left ventricle to right atrial shunt that was seen on preoperative ECHO. The atrial septal defect was repaired and a baffle was used to isolate blood flow across the accessory valve from the left atrium to the left ventricle. The patient was discharged on postoperative day 4 and has been doing well 2 years postoperatively.

Balloon-shaped cystic subaortic membrane.

A 22-year-old man with a 4 month history of dyspnoea on exertion was referred for echocardiography. Transthoracic echocardiography revealed a balloon-shaped cystic mass (2 x 2 cm) attached to the left ventricular outflow tract (LVOT). Continuous-wave Doppler echocardiography showed a 44 mmHg mean LVOT gradient. The patient underwent transoesophageal echocardiography for detailed echocardiographic examination of LVOT and aortic valve. Transoesophageal echocardiography revealed a balloon-shaped cystic mass originating from the LVOT at the aorto-mitral communication. In the operating theatre, a cystic ballooning subaortic membrane was found and excised successfully. The morphology of the membrane was similar to that shown by transoesophageal echocardiography.

Echocardiographic predictors of reoperation for subaortic stenosis in children and adults.

OBJECTIVES: Subaortic stenosis (SAS) can present as various types of obstruction of the left ventricular outflow tract (LVOT) below the level of the aortic valve. Even though corrective surgery has been identified as the most effective treatment, SAS more frequently reoccurs requiring reoperation in a significant proportion of the patients. Previous studies have focused on predictors of recurrence in various subgroups of patients with SAS, but rarely in the overall population of patients with SAS. The aim of this study was to determine the predictors of recurrence of SAS after initial corrective surgery. METHODS: Patients from the database of the Congenital Cardiology Department of the University Hospital of Southampton with significant SAS requiring corrective surgery were included in the study. Data retrieved were obtained and used to determine the predictors of SAS recurrence after the initial corrective surgery. RESULTS: Eighty-two patients (paediatric, n = 72 and adult, n = 10) who underwent initial successful resection were included in the analysis. Thirty patients required reoperation for recurrent SAS. These were significantly younger (median age 3.0 vs 6.7 years, P = 0.002). The recurrence of SAS was more common in patients with an interrupted aortic arch (23.3% vs 3.8%, P = 0.010) and unfavourable left ventricle geometry (43.3% vs 7.6%, P < 0.001), with steeper aortoseptal angle (131.0° ± 8.7° vs 136.1° ± 8.6°, P = 0.030), shorter distance between the point of obstruction of the LVOT and the aortic valve annulus in systole and diastole (median 4.30 vs 5.90 mm, P = 0.003 and 3.65 vs 4.95 mm, P = 0.006, respectively) and in those who had higher residual peak and mean LVOT gradients postoperatively (29.3 ± 16.0 vs 19.8 ± 10.7 mmHg, P = 0.006 and 15.9 ± 8.3 vs 10.1 ± 5.8 mmHg, P = 0.002, respectively). Overall, the presence of an interrupted aortic arch [odds ratio (OR) 10.34, 95% confidence interval (CI) 1.46-73.25; P < 0.019] and unfavourable left ventricle geometry (OR 10.42, 95% CI 1.86-58.39; P < 0.008) could independently predict reoperation for SAS after initial successful resection. CONCLUSIONS: Patients who have initial corrective surgery for SAS at a younger age, unfavourable left ventricle geometry, an interrupted aortic arch and higher early postoperative LVOT gradients are more likely to have recurrent SAS requiring reoperation.

Discrete subaortic stenosis in elderly women.

Discrete subaortic stenosis (DSS) is likely an acquired cardiac disorder which requires anatomic precursors and a genetic background. DSS occurs usually within the first decade, provoking rapidly progressive left ventricular outflow tract obstruction and secondary aortic regurgitation. DSS has been considered for a long time exclusively a disease of infancy and childhood and few reports and small series have described DSS in adulthood and only two cases are reported in elderly. Our case describes a discrete subaortic membranous ridge in an elderly woman with recent onset of dyspnea.

Multiplanar review analysis of three-dimensional echocardiographic datasets gives new insights into the morphology of subaortic stenosis.

AIMS: Associated left ventricular structures may play a role in progression and recurrence of discrete subaortic stenosis. The availability of a new 3D echocardiography tool, multiplanar review (MPR), allows comprehensive analysis of datasets in infinite planes, and detailed examination of anatomy. We sought to evaluate the role of MPR in defining the morphology of subaortic stenosis. METHODS: Consecutive patients underwent detailed 2 and 3D echocardiographic examination using MPR. RESULTS: Sixteen patients aged 0.7-15.9 years (median 4.57) with diagnosis as follows: isolated subaortic stenosis in nine, additional defects in seven (coarctation of aorta, VSD, mitral, or aortic stenosis). Position and extent of subaortic stenosis was clearly described by multiplanar review in all patients. Additional MPR findings were: abnormalities of mitral valve leaflet or chordal apparatus attachments (14 patients), abnormal ventricular muscle band (11), abnormal increased aorto-mitral separation (two). The aortoseptal angle was significantly decreased in subaortic stenosis, mean 141 +/- 12 degrees , vs. normal subjects, mean 153 +/- 6 degrees , P = 0.02. Surgical findings correlated well with MPR findings. CONCLUSIONS: MPR analysis of 3D datasets is a sensitive and accurate mode for delineation of morphological details of discrete subaortic stenosis, providing additional information to 2D echocardiography.

Correction of Left Ventricular Outflow Tract Obstruction Caused by Anomalous Papillary Muscle and Subaortic Membrane.

This paper presents a case study of a 30-year-old male patient with dyspnea on exertion had echocardiographic diagnosis of aortic subvalvar stenosis. Discrete mitral regurgitation and aortic valve dysplasia with mild to moderate insufficiency and hypertrophic cardiomyopathy were also noted. During surgery, a rare condition was identified: presence of papillary muscle anomaly associated with the subaortic membrane as a cause of obstruction of the left ventricular outflow tract. With the resection of these structures and a mitral valve annuloplasty, the patient evolved with a significant improvement of clinical condition and heart failure, with no residual mitral insufficiency.

56-year-old lady with transaortic gradient.

CLINICAL INTRODUCTION: A 56-year-old lady with a background of hypertension was admitted to our institution with acute pulmonary oedema. She reported gradual and increasingly severe dyspnoea on exertion over the preceding 12 months and, prior to presentation, her exercise tolerance was restricted to one flight of stairs. On transthoracic echocardiography during the index admission, left ventricular size and systolic function were normal, and peak and mean transaortic gradients were 67 mm Hg and 33 mm Hg, respectively, with a peak velocity of 3.9 m/s. No aortic incompetence or other significant valvular abnormality was noted. A transoesophageal echocardiogram was performed. Figure 1 depicts the mid-oesophageal parasternal long-axis view. What is the explanation behind the significant transaortic gradient?heartjnl;104/12/1036/F1F1F1Figure 1Transoesophageal echocardiogram, mid-oesophageal long-axis view at 135 degrees. QUESTION: What is the explanation behind the significant transaortic gradient?Ventricular septal defect Supravalvular aortic stenosisAortic valvular stenosisSubaortic membraneHypertrophic obstructive cardiomyopathy.

[Subaortic membrane in adults. A brief review of literature apropos of one case]. / Membrana subaórtica en adultos. Breve revisión de la literatura a propósito de un caso.

A 54-year-old man, ex smoker with high blood pressure and a history of possible Wolff-Parkinson-White syndrome was admitted for presenting an episode suggestive of acute coronary syndrome with immediate syncope and left bundle branch block, while performing physical activity. Angioplasty and a drug-eluting stent were performed in the left circumflex artery. Subsequently, Doppler echocardiography disclosed an image suggestive of a subaortic membrane. Given these findings, the patient underwent a 3D transesophageal echocardiogram and a magnetic resonance study, which confirmed the diagnosis of a subaortic membrane. In turn, in the Holter monitoring a paroxysmal pattern of Wolff-ParkinsonWhite was observed. The patient presented three possible causes of syncope. A stress echocardiogram elicited a gradient of 126 mm Hg, which could be possibly related to the syncopal episode that the patient suffered.

Paciente masculino de 54 años, ex fumador, hipertenso y con el antecedente no confirmado de síndrome de Wolff-Parkinson-White, que ingresó por haber presentado, mientras realizaba actividad física, un cuadro sugestivo de síndrome coronario agudo con inmediato episodio de síncope y bloqueo de rama izquierda, por lo que se le realizó una angiografía coronaria con posterior angioplastia y la colocación de un stent liberador de drogas en la arteria circunfleja. En el ecocardiograma Doppler se observó una imagen compatible con membrana subaórtica. Ante estos hallazgos se realizó un ecocardiograma transesofágico 3D y una resonancia magnética cardiaca que confirmaron el diagnóstico. A su vez se evidenció en el monitoreo Holter y de forma paroxística el patrón de Wolff-Parkinson-White. De esta manera, el paciente presentó tres posibles causas de síncope. Se realizó un ecocardiograma de esfuerzo, en el que el gradiente intraesfuerzo alcanzó los 126 mm Hg, lo que podría justificar el episodio del síncope.