Incidence and prognosis of obstruction of the left ventricular outflow tract in Liverpool (1960-91): a study of 313 patients

Double trouble - dual outflow tract obstruction in congenital heart disease: a case report

BACKGROUND

Double chambered right ventricle is a rare congenital heart disease that is characterised by the presence of an anomalous muscle bundle that divides the right ventricle into a low pressure superior (distal) chamber and a high pressure inferior (proximal) chamber. It is found in association with a ventricular septal defect in 90% cases with other associations being tetralogy of Fallot, transposition of great vessels, atrial septal defect and Ebstein's anomaly. On the other hand, subaortic membrane is a form of discrete subaortic stenosis that is characterised by a membranous diaphragm in the subvalvular location of the left ventricular outflow tract. Both of these entities are responsible for causing subvalvular outflow tract obstruction. The occurrence of double chambered right ventricle in association with subaortic membrane is an extremely rare entity with only a few case reports available in the literature.

CASE REPORT

A 13-year-old male child with history of chest pain and palpitations presented to the outpatient department of a tertiary care center. Transthoracic echocardiography revealed a subaortic membrane producing a pressure gradient across the left ventricular outflow tract with dilatation of the right atrium and right ventricle which could not be fully evaluated on echocardiography. Cardiac computed tomography was then performed which additionally revealed an anomalous muscle bundle coursing across the right ventricle from the septum to the subinfundibular region creating a double chambered right ventricle. The patient was then taken up for reconstruction of right ventricular outflow tract and resection of subaortic membrane.

CONCLUSION

Right and left outflow tract obstructions are rare congenital lesions which when seen in combination, become even more infrequent. Echocardiography is a robust tool that detects turbulent flow to identify such lesions. However, poor acoustic window may sometimes result in missing these lesions and computed tomography in such situations can play an important role in detection as well as complete preoperative imaging evaluation.

Sudden Cardiac Arrest During a Sedated Cardiac Magnetic Resonance Study in a Nonsyndromic Child with Evolving Supravalvar Aortic Stenosis Due to Familial ELN Mutation

Supravalvar aortic stenosis (SVAS) is a less common but clinically important form of left ventricular outflow tract obstruction, and commonly associated with Williams syndrome (WS). SVAS outside of WS may also occur sporadically or in a familial form, often with identifiable mutations in the elastin (ELN) gene. While risk of sudden cardiac death in patients with SVAS has been extensively described in the context of WS, less is known about risk in patients with isolated SVAS. We report a case of a nonsyndromic two-year-old boy with evolving manifestations of SVAS who developed sudden cardiac arrest and death during a sedated cardiac magnetic resonance imaging study. A strong family history of SVAS was present and targeted genetic testing identified an ELN gene mutation in the boy's affected father and other paternal relatives. We review risk factors found in the literature for SCA in SVAS patients and utilize this case to raise awareness of the risk of cardiac events in these individuals even in the absence of WS or severe disease. This case also underscores the importance of genetic testing, including targeted panels specifically looking for ELN gene mutations, in all patients with SVAS even in the absence of phenotypic concerns for WS or other genetic syndromes.

Managing uncertainty in decision-making of common congenital cardiac defects

Decision-making in congenital cardiac care, although sometimes appearing simple, may prove challenging due to lack of data, uncertainty about outcomes, underlying heuristics, and potential biases in how we reach decisions. We report on the decision-making complexities and uncertainty in management of five commonly encountered congenital cardiac problems: indications for and timing of treatment of subaortic stenosis, closure or observation of small ventricular septal defects, management of new-onset aortic regurgitation in ventricular septal defect, management of anomalous aortic origin of a coronary artery in an asymptomatic patient, and indications for operating on a single anomalously draining pulmonary vein. The strategy underpinning each lesion and the indications for and against intervention are outlined. Areas of uncertainty are clearly delineated. Even in the presence of "simple" congenital cardiac lesions, uncertainty exists in decision-making. Awareness and acceptance of uncertainty is first required to facilitate efforts at mitigation. Strategies to circumvent uncertainty in these scenarios include greater availability of evidence-based medicine, larger datasets, standardised clinical assessment and management protocols, and potentially the incorporation of artificial intelligence into the decision-making process.

Aortic Valve Surgery After Neonatal Balloon Aortic Valvuloplasty in Congenital Aortic Stenosis

[Figure: see text].

Valvular heart disease in congenital heart disease: a narrative review

Patients with congenital heart disease (CHD) are one of the fastest growing populations in cardiology, and valvular pathology is at the center of many congenital lesions. Derangements in valvular embryology lead to several anomalies prone to dysfunction, each with hemodynamic effects that require appropriate surveillance and management. Surgical innovation has provided new treatments that have improved survival in this population, though has also contributed to esotericism in patients who already have unique anatomic and physiologic considerations. Conduit and prosthesis durability are often monitored collaboratively with general and specialized congenital-focused cardiologists. As such, general cardiologists must become familiar with valvular disease with CHD for appropriate care and referral practices. In this review, we summarize the embryology of the semilunar and atrioventricular (AV) valves as a foundation for understanding the origins of valvular CHD and describe the mechanisms that account for heterogeneity in disease. We then highlight the categories of pathology from the simple (e.g., bicuspid aortic valve, isolated pulmonic stenosis) to the more complex (e.g., Ebstein's anomaly, AV valvular disease in single ventricle circulations) with details on natural history, diagnosis, and contemporary therapeutic approaches. Care for CHD patients requires collaborative effort between providers, both CHD-specialized and not, to achieve optimal patient outcomes.

Supravalvar aortic stenosis: Imaging characteristics and associations on multidetector computed tomography angiography

AIM

To evaluate the imaging features and associations in patients with supravalvar aortic stenosis on multidetector computed tomography (CT) angiography.

MATERIALS AND METHODS

We retrospectively reviewed all CT angiography studies performed for evaluation of congenital heart diseases at our institution through the period from January 2014 to June 2020. Cases with supravalvar aortic stenosis were identified and classified as syndromic and nonsyndromic based on history, physical examination, and relevant investigations. The type and extent of vascular involvement and associated cardiovascular abnormalities were characterized.

RESULTS

Supravalvar aortic stenosis was identified in 26/3926 (0.66%) patients (22 males and 4 females; Age range: 2 months to 20 years). Discrete stenosis was seen in 14/26 (53.8%) patients, while diffuse involvement of the ascending aorta to varying degrees was seen in the remaining 12 (46.2%) patients. About 15/26 (57.7%) patients had pulmonary involvement at some level, namely, infundibular, valvar, supravalvar, or peripheral pulmonic stenosis while 15/26 (57.7%) patients had coronary arterial involvement either in the form of stenosis, occlusion, or ectasia. Aortic valvular abnormality including thickening, partial fusion, and adhesion of leaflet edges to the sinutubular junction causing reduced coronary inflow was seen in 15/26 (57.7%) patients. Associated ventricular septal defect, patent ductus arteriosus, and mitral valvular prolapse were seen in four (15.4%), five (19.2%), and two (7.7%) patients respectively.

CONCLUSION

Supravalvar aortic stenosis is a rare abnormality showing associated pulmonary arterial involvement, coronary arterial involvement, aortic valvular abnormalities, and associated congenital cardiac defects in the majority of cases, which may influence surgical outcomes.

Surgical Valvuloplasty Versus Balloon Dilation for Congenital Aortic Stenosis in Pediatric Patients

BACKGROUND

For children with congenital aortic stenosis (AS) who are candidates for biventricular repair, valvuloplasty can be achieved by surgical aortic valvuloplasty (SAV) or by transcatheter balloon aortic dilation (BAD). We aimed to evaluate the longer term outcomes of SAV versus BAD at our institution.

METHODS

We retrospectively reviewed the outcomes of 2 months to 18 years old patients who underwent SAV or BAD at our institution between January 1990 and July 2018. Baseline and follow-up characteristics were assessed by echocardiography. Long-term survival, freedom from reintervention, freedom from aortic valve replacement (AVR), and aortic regurgitation were evaluated.

RESULTS

A total of 212 patients met inclusion criteria (SAV = 123; BAD = 89). Age, sex, aortic insufficiency (AI), and aortic valve gradient were similar between the groups. At 10 years, 27.9% (19/68) of SAV patients and 58.3% (28/48) of BAD patients had moderate or worse AI (P = .001), and reintervention occurred in 39.2% (29/74) of SAV patients and 78.6% (44/56) of BAD patients (P < .001). Kaplan-Meier analysis revealed overall survival was 96.8% (119/123) for SAV and 95.5% (85/89) for SAV (P = .87). At 10 years, 35% (23/66) of SAV patients and 54% (23/43) of BAD patients underwent AVR (P = .213).

CONCLUSIONS

Surgical aortic valvuloplasty demonstrated greater gradient reduction, less postoperative and long-term AI, and a lower reintervention rate at 10 years than BAD. There was no difference in survival or AVR reintervention rate. Surgical aortic valvuloplasty is a durable and efficacious intervention and should continue to be considered a favorable choice for palliation of valvular AS.

Rapid right ventricular pacing for balloon aortic valvuloplasty: expanding its routine use in neonates and infants

OBJECTIVE

Rapid right ventricular pacing during balloon aortic valvuloplasty is commonly used to achieve balloon stability in children and adults. There is no consensus for the use of the technique in neonates and infants. We sought to review our institutional experience with rapid right ventricular pacing-assisted balloon aortic valvuloplasty across all age groups and evaluate the safety and effectiveness of the technique in the sub-group of neonates and infants <12months.

METHODS

Retrospective study between February, 2011 and February, 2020.

RESULTS

A total of 37 patients (Group I: 21 neonates/infants <12months and Group II: 16 children 12 months-16 years) were analysed. Catheter-measured left ventricular to aortic gradient reduced from median of 66 mmHg (with a range from 30 to 125 mmHg) to 14 mmHg (with a range from 5 to 44 mmHg) in Group I and 44 mmHg (with a range from 28 to 93 mmHg) to 18 mmHg (with a range from 2 to 65 mmHg) in Group II (p < 0.001). Procedure and fluoroscopy times were identical in the two groups. Balloon:annulus ratio was 0.94 and 0.88 in Groups I and II, respectively. Freedom from reintervention was 100% for Group I at a median time of 3.2 years and 81% at 2.7 years for Group II. Reinterventions in Group II (3/16 pts) were performed predominantly for complex left ventricular outflow tract stenosis. At follow-up echocardiogram, 45% of patients in Group I had no aortic regurgitation, 30% trace-mild, 20% mild-moderate, and 5% moderate aortic regurgitation, whereas in Group II, 50% of patients had no aortic regurgitation, 32% had mild aortic regurgitation, and 18% mild-moderate aortic regurgitation. Unicuspid valves were only encountered in Group 1 (2/21 pts, 10%) and they were predictive of mild-aortic regurgitation during follow-up (p = 0.003). Ventricular fibrillation occurred in three neonates with suspicion of myocardial ischemia on the pre-procedure echocardiogram. All were successfully defibrillated.

CONCLUSIONS

Rapid right ventricular pacing can be expanded in neonates and infants to potentially decrease the incidence of aortic regurgitation and reintervention rates, hence avoiding high-risk surgical bail-out procedures for severe aortic regurgitation in the first year of life. Myocardial ischemia may predispose to ventricular dysrhythmias during rapid right ventricular pacing.

Rapid right ventricular pacing for balloon valvuloplasty in congenital aortic stenosis: A systematic review

BACKGROUND

Balloon aortic valvuloplasty (BAV) is a well-established treatment modality for congenital aortic valve stenosis.

AIM

To evaluate the role of rapid right ventricular pacing (RRVP) in balloon stabilization during BAV on aortic regurgitation (AR) in pediatric patients.

METHODS

A systematic review of the MEDLINE, Cochrane Library, and Scopus databases was conducted according to the PRISMA guidelines (end-of-search date: July 8, 2020). The National Heart, Lung, and Blood Institute and Newcastle-Ottawa scales was utilized for quality assessment.

RESULTS

Five studies reporting on 72 patients were included. The studies investigated the use of RRVP-assisted BAV in infants (> 1 mo) and older children, but not in neonates. Ten (13.9%) patients had a history of some type of aortic valve surgical or catheterization procedure. Before BAV, 58 (84.0%), 7 (10.1%), 4 (5.9%) patients had AR grade 0 (none), 1 (trivial), 2 (mild), respectively. After BAV, 34 (49.3%), 6 (8.7%), 26 (37.7%), 3 (4.3%), patients had AR grade 0, 1, 2, and 3 (moderate), respectively. No patient developed severe AR after RRVP. One (1.4%) developed ventricular fibrillation and was defibrillated successfully. No additional arrhythmias or complications occurred during RRVP.

CONCLUSION

RRVP can be safely used to achieve balloon stability during pediatric BAV, which could potentially decrease AR rates.

Subaortic Membrane and Patent Ductus Arteriosus in Rare Association-Case Series

BACKGROUND

The combination of subaortic membrane (SAM) and patent ductus arteriosus is very rare. Subaortic stenosis is the second most common form of left ventricular outflow tract (LVOT) obstruction after valvular aortic stenosis. We are reporting the largest case series of SAM and PDA.

METHODS

We included all patients that were diagnosed with the combination of SAM and PDA at our cardiac center. We have reviewed patients echocardiographic studies, cardiac catheterizations, surgical notes and all the outpatients notes.

RESULTS

We have a total of 7 patients. The age at presentation was in the early childhood with 3 patients diagnosed in infancy. Four patients had severe and moderate LVOT obstruction with SAM being very close to the aortic valve and all required surgical intervention. The last three patients had mild LVOT obstruction 2 of them with the SAM being > 4mm away from the aortic valve. Six out of the seven patients had intervention while the last one is under clinical follow up currently. PDA closure did not change the outcome. There were no other postoperative complication like developing new AI or developing complete heart block. There was no relation between gender, height, weight or age at diagnosis to the SAM clinical course.

CONCLUSION

SAM and PDA association is very rare. The underlying pathophysiology is not well understood. When the SAM is closer to aortic valve (≤ 4mm), it carries higher risk of progressive LVOT obstruction. The interventions for SAM and PDA were safe procedures.

Surgical versus balloon valvotomy in neonates and infants: results from the UK National Audit

Objective

There are conflicting data on choosing balloon aortic valvoplasty (BAV) or surgical aortic valvotomy (SAV) in neonates and infants requiring intervention for aortic valve stenosis. We aim to report the outcome of both techniques based on results from the UK national registry.

Methods

This is a retrospective study, including all patients under 1 year undergoing BAV/SAV between 2000 and 2012. A modulated renewal approach was used to examine the effect of reinterventions on outcomes.

Results

A total of 647 patients (488 BAV, 159 SAV, 292 neonates) undergoing 888 aortic valve procedures were included, with a median age of 40 days. Unadjusted survival at 10 years was 90.6% after initial BAV and 84.9% after initial SAV. Unadjusted aortic valve replacement (AVR) rate at 10 years was 78% after initial BAV and 80.3% after initial SAV. Initial BAV and SAV had comparable outcomes at 10 years when adjusted by covariates (p>0.4). AVR rates were higher after BAV and SAV reinterventions compared with initial valvoplasty without reinterventions (reference BAV, HR=3 and 3.8, respectively, p<0.001). Neonates accounted for 29/35 of early deaths after the initial procedure, without significant differences between BAV and SAV, with all late outcomes being worse compared with infants (p<0.005).

Conclusions

In a group of consecutive neonates and infants, BAV and SAV had comparable survival and freedom from reintervention as initial procedures and when performed as reinterventions. These findings support a treatment choice based on patient characteristics and centre expertise, and further research into the best patient profile for each choice.

Does Presence of Discrete Subaortic Stenosis Alter Diagnosis and Management of Concomitant Valvular Aortic Stenosis?

•

Adults with SM have slower hemodynamic progression and more rapid AS progression.

•

Changes in LVOT velocities are minimal over time.

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Presence of SM with AS poses challenges in determining hemodynamic significance.

•

In general, surgery should be recommended when AS is severe and symptoms develop.

Routine Septal Myectomy During Subaortic Stenosis Membrane Resection: Effect on Recurrence Rates

Recurrence of subaortic stenosis (SubAS) is up to ~ 19% following resection. Historically, treatment has consisted of membrane resection alone. This study investigated the effect of routine septal myectomy in addition to membrane resection. A single-center retrospective review was performed in all patients < 18 years of age undergoing membrane resection with septal myectomy for SubAS from 2003 to 2013. Demographic, perioperative, and follow-up data were collected. Freedom from reoperation and risk factors for reoperation were determined. 107 patients (median age 4.8 years) were included. There was one in-hospital death, five patients (5%) requiring pacemaker, and no iatrogenic ventricular septal defects. Follow-up was 80% complete and median follow-up was 4.9 years (range 0.5-12 years). Fourteen (16%) subjects required reoperation. Freedom from reoperation was 98% at 1 year, 86% at 5 years, and 69% at 10 years (Fig. 1). There was no difference in decrease of peak gradient between subjects who did and did not require reoperation (- 47 vs. - 40 mmHg; p = 0.59). In univariate analysis, chromosomal anomaly (hazard ratio [HR] 5.0, p = 0.02), smaller body surface area (HR 0.1, p = 0.03), and younger age at surgery (HR 0.7, p = 0.01) were significantly associated with reoperation. The routine use of myectomy with membrane excision did not result in a lower rate of reoperation or higher rates of complications compared to historical controls. Younger age, smaller size, and chromosomal anomaly were associated with increased risk for reoperation. Patients with these risk factors may benefit from more intensive long-term follow-up.

Subaortic Stenosis Resection in Children: Emphasis on Recurrence and the Fate of the Aortic Valve

Background:

Recurrence after surgical resection of discrete subvalvar aortic stenosis in children often requires repeat operation. Risk factors for recurrence are poorly understood. We sought to determine potential risk factors for recurrence and postoperative comorbidities in the long term.

Methods:

Retrospective chart review was performed on all pediatric patients who underwent surgical resection of discrete subaortic stenosis at our institution. Demographics, perioperative findings, and clinical data were analyzed for predisposing factors.

Results:

From 1991 to 2015, a total of 104 patients underwent primary surgical resection of discrete subaortic stenosis. There were no postoperative deaths. Three (2.9%) patients required pacemaker implantation. Nine (8.4%) patients required repeat resection for recurrence of subaortic membrane over a median follow-up of 8.5 years (interquartile range: 5.9-13.5 years). Actuarial freedom from repeat resection was 100%, 94%, and 82% at one, five, and ten years, respectively. Repeat resection occurred more frequently in patients with genetic disease (37.5% vs 10.7%; P = .033) and preoperative mitral regurgitation (MR; 25% vs 1.2%; P < .001). Postoperative aortic insufficiency (AI) that was moderate or worse was associated with older age at the time of first resection (relative risk [RR]: 1.54, P < .05), moderate or severe preoperative AI (RR: 1.84, P = .002), and repeat resection of subaortic stenosis (RR: 1.90, P < .001).

Conclusion:

The majority of children who undergo surgical resection of subaortic stenosis will not experience recurrence in childhood and those who do require repeat resection may have a higher incidence of genetic disease and preoperative MR. Postoperative AI is associated with repeat resection, older age at the time of surgery, and degree of preoperative AI.

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.

Fixed left ventricular outflow tract obstruction mimicking hypertrophic obstructive cardiomyopathy: pitfalls in diagnosis

We present a case series that highlights the diagnostic challenges with left ventricular hypertrophy (LVH) and left ventricular outflow tract obstruction (LVOTO). Fixed structural lesions causing LVOTO with secondary LVH may mimic hypertrophic obstructive cardiomyopathy (HOCM). Management of these two entities is critically different. Misdiagnosis and failure to recognize fixed left ventricular outflow tract (LVOT) lesions may result in morbidity as a result of inappropriate therapy and delay of definitive surgical treatment. It is thus necessary to identify the correct type and level of obstruction in the LVOT by careful correlation of clinical examination, Doppler evaluation, and advanced imaging findings.

Syncope secondary to left ventricular outflow tract obstruction, an interesting presentation of infective endocarditis

We describe a case of a 74-year-old woman who presented with symptoms of fever and lethargy, associated with an episode of cardiac syncope and exertional shortness of breath (SOB). She was diagnosed with Staphylococcus aureus infective mural endocarditis (IE) and subsequent transoesophageal echocardiogram (TOE) confirmed this diagnosis. As the vegetative mass arose from the septal wall, an unusual location, it caused left ventricular outflow tract (LVOT) obstruction and therefore behaved similarly to a subaortic valvular stenosis. There were no conduction abnormalities on the ECG and no clinical or echocardiographic features of congestive heart failure. The finding of LVOT obstruction explained the unusual presentation with syncope and exertional SOB making this case unique. Owing to the large vegetative mass and thereby its high risk of septic emboli, the patient underwent successful surgical resection of the mass with resolution of the obstruction. She successfully completed intravenous antibiotics and was discharged from hospital.

Surgery for simple and complex subaortic stenosis in children and young adults: results from a prospective, procedure-based national database

OBJECTIVE

To identify the outcomes of surgically treated subaortic stenosis in a national population.

METHODS

From 2000 to 2013, 1047 patients aged < 40 years underwent 1142 subaortic stenosis procedures. Of the 1047 patients, 484 (46.2%) were considered to have complex stenosis (CS) because at or before the first operation they had mitral valve (MV) disease, aortic valve disease, aortic coarctation or an interrupted aortic arch.

RESULTS

The 30-day mortality was 0.7% for simple stenosis (SS), 2.3% for CS (P = .06), and 1.6% overall. Age < 1 year (P < .01), MV procedure (P = .02) and an interrupted aortic arch at the index procedure (P < .01) were risk factors for early death. Konno-type procedure early mortality was 2.4%. The 12-year survival was 97.1%, with a significant difference between SS and CS (hazard ratio [HR], 4.53; P = .02). Having MV disease alone (HR, 4.11; P = .02), MV disease plus aortic coarctation (HR, 6.73; P = .008), and age < 1 year (HR, 6.72; P < .001) were risk factors for late mortality. Freedom from subaortic reintervention overall was 92.3% and 88.5% at 5 and 12 years, respectively, much greater with CS than with SS (HR, 4.91; P < .0001). The independent risk factors for reintervention were younger age at the index procedure (HR, 0.1/y; P = .002), concomitant MV procedure (HR, 2.68; P = .019), ventricular septal defect plus interrupted aortic arch (HR, 3.19; P = .014), and ventricular septal defect plus aortic coarctation (HR, 2.41; P = .023). Undergoing a concomitant aortic valve procedure at the index procedure was protective (HR, 0.29; P = .025).

CONCLUSIONS

Patients with SS had excellent outcomes. However, those with CS had worse long-term survival and freedom from reintervention, with morbidity and mortality greatest in young patients with multiple lesions. Additional evaluation in large-scale prospective studies is warranted.

A calcified sinutubular junction: the discovery of a supravalvular aortic stenosis in an elderly woman

We report a case of a 64 year old woman with a calcified ring at the level of the sinotubular junction. Echocardiography and Computed Tomography showed a supravalvular aortic stenosis, without known associated lesions, except for the existence of an aberrant right subclavian artery. These combination of abnormalities makes it an unique case. Differential diagnosis of sinutubular calcification is added. From the literature a short review of supravalvular aortic stenosis is presented with indications for surgical intervention. Lifelong and regular follow up is necessary.

Subvalvular aortic stenosis diagnosed by 3D transesophageal echocardiography

The patient was a 13-year-old male with chief complaints of exertional chest pain and dyspnea. Cardiac murmur was suspected in a medical checkup at 1 month old, at which time he was diagnosed with subvalvular aortic stenosis. He had subsequently been under follow-up observation at a nearby hospital for subvalvular aortic stenosis. He was admitted to our department for surgery due to aggravation of symptoms that had occurred over the previous year. Transthoracic echocardiography after admission showed an abnormal structure in the subvalvular aortic area, and the maximum pressure gradient between the left ventricle and aortic valve was 84 mmHg. The preoperative valve area was 0.71 cm(2), as measured by the Doppler method. Measurement of valve area by the trace method was difficult. Transesophageal echocardiography (TEE) showed a septum-like structure extending from the ventricular septum in the subvalvular area. On 3D TEE, the valve areas in the systolic and diastolic phases were 0.86 and 0.49 cm(2), respectively. Postoperative echocardiography showed resection of the structure in the subvalvular area, and the postoperative course was favorable.

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.

Cardiac catheterization and operative outcomes from a multicenter consortium for children with williams syndrome

Williams syndrome is a multifaceted disorder that includes a spectrum of cardiovascular anomalies. Due to its rare occurrence, outcome data for operations and cardiac catheterization are limited. We reviewed data from 242 individuals from the Pediatric Cardiac Care Consortium (PCCC) with Williams syndrome and associated cardiovascular lesions, and their frequency, and assessed their effects on mortality. In the PCCC, from 1984 to 1999 there were approximately 100,000 entries for cardiac procedures, involving more than 62,000 patients. The diagnosis of Williams syndrome was based on clinical features and determined by each site. Most patients were diagnosed with the availability of the FISH probe for region 7q11.23. Using a spreadsheet application, Microsoft Excel, the selected patients were analyzed for various types of cardiac anomalies. The most common cardiovascular lesions and the mortality rate in patients with Williams syndrome were examined. A complete tabulation of all cardiovascular lesions was assembled. There were 292 catheterizations and 143 operations reported to the PCCC. One hundred six patients had both an operation and a catheterization. The three main cardiovascular anomalies were supravalvular aortic stenosis (SVAS; 169), pulmonary artery stenosis (PAS; 130), and coarctation or aortic arch hypoplasia (Arch; 32). One hundred five patients had a single lesion, 70 with SVAS, 29 with PAS, and 6 with an arch anomaly. Ninety-two had more than one lesion: 80 with SVAS and PAS, 7 with PAS and Arch, and 5 with SVAS and Arch. Seventy individuals have only SVAS, 29 PAS, and 6 Arch alone. There was a total of 15 deaths. The mortality rate was highest in the group with the combination of SVAS and PAS (7 surgical and 5 catheter; 12 of 80 patients [15%]; p = 0.0001, chi(2)). In conclusion, our data represent the largest collection of individuals with Williams syndrome who underwent cardiac catheterization and/or operation. The data suggest that children with Williams syndrome and bilateral outflow tract obstruction have statistically and clinically significantly higher mortality associated with catheterization or operation.

Hypertrophic cardiomyopathy presenting as restrictive cardiomyopathy: a case complicated by biventricular apical aneurysms and papillary fibroelastoma

This report describes a 45-year-old male patient with nonobstructive hypertrophic cardiomyopathy, biventricular apical aneurysms, and papillary fibroelastoma. Histology revealed muscle fiber disarray, interstitial fibrosis, and mural vessel changes. The wall of the aneurysms showed fat infiltration, and loss and replacement of muscle fibers with fibrous tissues. A review of the literature suggests that this case is the first reported experience with the three pathologies occurring in combination.

Aortic stenosis: the spectrum of practice

There is significant variation in practice patterns in managing congenital aortic valve stenosis. Review of medical literature reveals no significant information regarding the current practice methods in the treatment of a simple lesion such as aortic stenosis (AS). Therefore, this survey-based study was conducted in an attempt to better understand the uniformity or heterogeneity of practice in treating AS. A questionnaire was prepared to evaluate the style of management of AS. This survey was designed to assess the practice of follow-up visitations, type and frequency of investigative studies, pharmacological therapy, and exercise recommendations. Questions about therapeutic intervention included those of timing and type of intervention. Questionnaires were sent to all academic pediatric cardiology programs in the United States (48 program) and selected international programs from Europe, Asia, and Australasia (19 program). The total number of surveys sent out was 67, and the total number of respondents was 25 (37%), 15 (31%) from the United States and 9 (53%) from outside the United States. The definition of moderate AS varied among respondents. The range provided for mild AS was identified as that with a peak-to-peak pressure gradient of < 25-30 mmHg, peak instantaneous Doppler gradient of < 36-50 mmHg, or mean Doppler gradient of < 25-40 mmHg. On the other hand, severe AS was defined as that with a peak-to-peak gradient of > 50-60 mmHg, peak instantaneous Doppler gradient of > 64-80 mmHg, or mean Doppler gradient of > 45-64 mmHg. In assessing follow-up patterns, 84% of respondents recommended seeing patients with mild AS annually, the longest time of follow-up listed in the questionnaire, whereas 20% suggested follow-up every 6 months. There was no consensus among survey centers regarding follow-up of patients with moderate AS. For severe AS, 16% recommend immediate intervention, 16% arrange follow-up every 6 months, and 56 and 28% recommend follow-up in 3 and 1 month(s), respectively. In making the decision to proceed with biventricular versus univentricular repair in patients with AS in the neonatal period, many factors were considered. Ninety-two percent of respondents rely on mitral valve z score, 84% on aortic valve z score, 52% on left ventricle length, 48% on the presence of antegrade ascending aorta flow, and only 32% considered significant endocardial fibroelastosis as a factor. Rhodes score was used by 20% of respondents in decision making regarding the approach to management of this subset of AS. This study shows that there is consensus in the management of mild and severe forms of AS. As expected, disagreement is present in the definition, evaluation, and therapy of moderate aortic valve stenosis. There is a tendency for catheter intervention except in the presence of dysplastic aortic valve or moderate to severe aortic regurgitation. There is also disagreement regarding methods used to determine biventricular versus univentricular repair of a borderline hypoplastic left heart.

Management strategy for very mild aortic valve stenosis

It is unclear how often patients with very mild aortic stenosis (gradients < 25 mmHg) need interval follow-up. The purpose of this study was to define the determinants of disease severity progression and to propose appropriate management strategies. It is known that congenital aortic stenosis is a progressive disease that requires long-term follow-up at consistent intervals. We studied 89 patients with very mild aortic stenosis. Cox proportional hazard modeling was performed to ascertain predictors of morbidity and mortality. Events were defined as valve surgery or death. Of the original 89 patients, 7 died (92% survival); one death was sudden and unexplained and six were noncardiac. Eighteen individuals were lost to follow-up (10 not located and 8 refused participation). Twelve (17%) had valve surgery. The minimum time interval between initial diagnosis of very mild aortic stenosis and surgery was 4.6 years (mean, 14.0). Age at diagnosis, gender, initial gradient, initial gradient/age, and aortic regurgitation were found not to be predictive of outcome. However, the slope of the transaortic gradient [change of gradient/time (years)] was predictive of outcome (hazard ratio of 1.69; confidence interval, 1.4-2.2). At least 17% of these patients progress to require operation. For patients with a gradient slope < 1.1, evaluation every 4 or 5 years is recommended. For patients with a gradient slope > 1.2, evaluation every 1 or 2 years seems prudent.

Natural history and surgical outcomes for isolated discrete subaortic stenosis in children

OBJECTIVE

To document the natural history and surgical outcomes for discrete subaortic stenosis in children.

DESIGN

Retrospective review.

SETTING

Tertiary care paediatric cardiology centres.

PATIENTS

92 children diagnosed between 1985 and 1998.

MAIN OUTCOME MEASURES

Echocardiographic left ventricular outflow gradient (echograd), and aortic insufficiency (AI).

RESULTS

The mean (SEM) age at diagnosis was 5.3 (0.4) years; the mean echograd was 30 (2) mm Hg, with AI in 22% (19/87) of patients. The echograd and incidence of AI increased to 35 (3) mm Hg and 53% (36/68) (p < 0.05) 3.6 (0.3) years later. The echograd at diagnosis predicted echograd progression and appearance of AI. 42 patients underwent surgery 2.2 (0.4) years after diagnosis. Preoperatively echograd and AI incidence increased to 58 (6) mm Hg and 76% (19/25) (p < 0.05). The echograd was 26 (4) mm Hg 3.7 (0.4) years postoperatively, with AI in 82% (31/38) of patients. Surgical morbidities included complete heart block, need for prosthetic valves, and iatrogenic ventricular septal defects. Eight patients underwent reoperation for recurrent subaortic stenosis. The age at diagnosis of 44 patients followed medically and 42 patients operated on did not differ (5.5 (0.6) v 5. 0 (0.6) years, p < 0.05). However, the echograd at diagnosis in the former was less (21 (2) v 40 (5) mm Hg, p < 0.05) and did not increase (23 (2) mm Hg) despite longer follow up (4.1 (0.4) v 2.2 (0. 4) years, p < 0.05). The incidence of AI at diagnosis and at last medical follow up was also less (14% (6/44) v 34% (13/38); 40% (17/43) v 76% (19/25), p < 0.05).

CONCLUSIONS

Many children with mild subaortic stenosis exhibit little progression of obstruction or AI and need not undergo immediate surgery. Others with more severe subaortic stenosis may progress precipitously and will benefit from early resection despite risks of surgical morbidity and recurrence.

Coarctation of the aorta: A call for early detection

BACKGROUND

Early repair of coarctation of the aorta (COA) is associated with few perioperative complications and better long-term outcome. Therefore, early detection and treatment of COA patients is extremely desirable. The aim of this study was to review our referral system, the effectiveness of neonatal screening examination, and orient physicians about this abnormality, the mode and age of presentation, differences in presentation between cases with isolated COA, and cases associated with other cardiac lesions.

PATIENTS AND METHODS

This was a retrospective study of 61 inpatients admitted to our hospital between January 1989 and December 1996, who were found to have COA. Referral data was analyzed and compared to hospital cardiac evaluation findings.

RESULTS

All the patients were referred after being symptomatic, but there was no suspicion of COA in any of the cases. One of the patients was referred by a pediatrician from a private clinic, and the rest by hospital pediatricians. Femoral pulse and cardiac murmur were commented upon in only three of the referral letters. Systolic pressure gradient (SPG) between upper and lower limbs and systolic hypertension were not commented on in any of the referral letters. SPG >/=10 mm Hg and systolic hypertension were found in 100% and 58% of the patients, respectively, upon evaluation in our center. SPG in patients with COA associated with other cardiac lesions was significantly lower than in patients with isolated COA (P=0.02).

CONCLUSION

Increased awareness in our primary health physicians of the importance of the neonatal screening examination and of measuring blood pressure in the limbs to detect COA early is needed. Timing of the neonatal screening examination between the third day and the third week is recommended. Systolic pressure gradient is a reliable method to detect COA, and in the lower significant range (>/=10 mm Hg) is associated with complex cardiac lesion rather than isolated COA.

Development and validation of an echocardiographic model for predicting progression of discrete subaortic stenosis in children

The clinical course of discrete subaortic stenosis (DSS) varies considerably between patients. This study was performed to identify echocardiographic characteristics of DSS that distinguish progressive from nonprogressive disease. The study included 100 patients from 2 institutions and was performed in 2 stages. In phase I, a prediction model was developed based on multivariate analysis of morphometric and Doppler variables obtained from the initial echocardiogram in 52 children with DSS from Texas Children's Hospital. In phase II, the performance characteristics of the prediction model were tested in 48 patients with DSS followed at Children's Hospital in Boston. Patients were divided into 3 outcome groups: nonprogressive, progressive, and intermediate progression. In phase I, multivariate analysis identified 3 independent predictors of progressive disease: indexed aortic valve to subaortic membrane distance, anterior mitral leaflet involvement, and initial Doppler gradient. The logistic regression equation--Probability = [1 + e-(-322+0.334X1+4.06X2-0.708X3)](-1), where X = initial gradient in mm Hg; X2 = absence (0) or presence (1) of mitral leaflet involvement; and X3 = indexed distance between aortic valve and subaortic membrane in mm/body surface area0.5 were used to predict progression. When the prediction model was applied to phase II study patients, none of the patients with nonprogressive DSS had a prediction value > 0.29 and none of the patients with progressive DSS had a prediction value < 0.58. Thus, a prediction value > 0.55 yielded a 100% sensitivity and 100% specificity for distinguishing progressive from nonprogressive DSS. Patients with intermediate progression were indistinguishable from progressive DSS but were clearly separable from nonprogressing patients. We conclude that progressive subaortic obstruction in children with DSS can be predicted from morphologic, morphometric, and Doppler echocardiographic analysis of left ventricular outflow.

Posterior deviation of left ventricular outflow tract septal components without ventricular septal defect

OBJECTIVE

To describe 11 patients with narrowing of the left ventricular outflow tract caused by angular posterior deviation of both the outlet septum and the upper part of trabecular septum, which was diagnosed by cross sectional echocardiography in all and confirmed by angiocardiography in seven.

RESULTS

Four patients had a subaortic systolic pressure gradient ranging from 23 to 70 mm Hg by Doppler echocardiography; cardiac catheterisation showed a significant (60 and 104 mm Hg) systolic pressure gradient in two. In four cases aortic regurgitation and two tricuspid pouches were shown by Doppler echocardiography, angiocardiography, or both. Four cases had a ridge at the angulation point on echocardiographic examination. Three patients were operated on for systolic pressure gradients of the left ventricular outflow tract and one for severe aortic regurgitation. There was proliferation of collagen-rich fibrous tissue in the subendocardial region on histopathological examination of the myectomy material. A ventricular septal defect had been diagnosed previously by contrast echocardiography in one patient; thus ventricular septal defects may close spontaneously over a period of time including fetal life. A subaortic ridge was detected in one patient at follow up.

CONCLUSIONS

Deviation of the outlet and trabecular septa should be considered as a cause of ventricular outflow tract obstruction even when no ventricular septal defect is present.

Prognosis of supravalve aortic stenosis in 81 patients in Liverpool (1960-1993)

OBJECTIVE

To determine the prognosis of supravalve aortic stenosis into early adult life and the factors affecting this prognosis.

DESIGN

81 patients with supravalve aortic stenosis were followed for a median duration of 8.3 (range 1 to 29) years.

PATIENTS

40 patients (49.4%) had Williams' syndrome, 18 (22.2%) familial supravalve aortic stenosis, 18 (22.2%) sporadic supravalve aortic stenosis, and five (6.2%) other syndromes. Nineteen patients had additional levels of left ventricular outflow tract obstruction.

RESULTS

47 patients (58%) underwent operation; 20% within a year of presentation. Multivariable analysis predicted that 88% of patients would undergo intervention within 30 years of follow up. The chance of intervention was increased by more severe aortic stenosis at presentation and the presence of multilevel obstruction in patients with sporadic supravalve aortic stenosis. Three deaths occurred before operation and 13 within a month of operation. Ten (62.5%) of the postoperative deaths were in patients with multilevel obstruction. Predicted survival 30 years after presentation was 66%. Risk factors for survival were age and severity of aortic stenosis at presentation. Multilevel obstruction did not emerge as a significant risk factor for death because of the high association with the severity of stenosis at presentation. 74% of survivors had mild or insignificant stenosis at follow up.

CONCLUSIONS

Long-term survival is related to age and the severity of aortic stenosis at presentation. Most patients will require intervention, and most survivors will have mild stenosis.