Mechanism of acquired right ventricular outflow tract obstruction in patients with ventricular septal defect: an angiocardiographic study

Double-chambered right ventricle in a patient with pulmonary atresia and ventricular septal defect

Double-chambered right ventricle is a rare form of right ventricular outflow tract obstruction caused by anomalous hypertrophy of muscle bundles in right ventricle. Cases most often occur in children and rarely in adults. Most cases (80-90%) are associated with ventricular septal defect. We describe a case of pulmonary atresia and ventricular septal defect with double-chambered right ventricle. The interesting clinical findings, ECG, echocardiography and angiocardiography features are described here.

Acquired infundibular pulmonary stenosis associated with a congenital membranous ventricular septal defect (Gasul phenomenon) in a dog and discussion regarding causes of infundibular stenosis

An aclinical Havanese dog was diagnosed with a membranous restrictive ventricular septal defect. The patient was represented later in their natural history due to the development of syncope. At that time the patient was diagnosed with acquired pulmonary infundibular stenosis. Balloon dilation of the stenosis was performed successfully twice over the patient's lifetime. The patient died suddenly approximately 14 months after the second balloon dilation. A discussion regarding primary infundibular pulmonary stenosis versus causes of acquired infundibular pulmonary stenosis including anomalous muscle bundles (double chamber right ventricle), tetralogy of Fallot, and infundibular stenosis is presented.

A six-chambered heart: cor triatriatum sinister with double-chambered right ventricle in association with ventricular septal defect

Background

Cor triatriatum has been described as a heart with three atria in which the left atrium (cor triatriatum sinistrum) or right atrium (cor triatriatum dextrum) is divided into two compartments by a fold of tissue, a membrane, or a fibromuscular band. Double-chambered right ventricle, on the other hand, is identified by the presence of an anomalous muscle bundle dividing the right ventricle into two chambers.

Case presentation

Here, we describe the case of a child who had a combination of both of these rare entities, effectively creating a heart with six chambers. The child underwent a successful intracardiac repair.

Conclusions

The association of CTS with DCRV forming a “6-chambered heart” is extremely rare. Awareness of its existence and accurate preoperative diagnosis has important implications in its surgical repair with all the components of this disease spectrum, further increasing the complexity of a successful surgical repair.

Congenital, acquired, or both? The only two congenitally based, acquired heart diseases

Discrete subaortic stenosis (DSS) is a type of left ventricular outflow tract obstruction whereas double-chambered right ventricle is a form of right ventricular outflow tract obstruction. Both of these cardiac malformations share lots of similar characteristics which classify them as acquired developmental heart diseases despite their congenital anatomical substrate. Both of them are frequently associated to ventricular septal defects. The initial stimulus in their pathogenetic process is anatomical abnormalities or variations. Subsequently, a hemodynamic process is triggered finally leading to an abnormal subaortic fibroproliferative process with regard to DSS or to hypertrophy of ectopic muscles as far as double-chambered right ventricle is concerned. In many cases, these pathologies are developed secondarily to surgical management of other congenital or acquired heart defects. Moreover, high recurrence rates after initial successful surgical therapy, particularly regarding DSS, have been described. Finally, an interesting coexistence of DSS and double-chambered aortic ventricle has also been reported in some cases.

Early and late outcomes of surgical repair of double-chambered right ventricle: a single-centre experience

OBJECTIVE

Double-chambered right ventricle is characterised by division of the outlet portion of the right ventricle by hypertrophy of the septoparietal trabeculations into two parts. We aim to report our experiences regarding the presenting symptoms of double-chambered right ventricle, long-term prognosis, including the recurrence rate and incidence of arrhythmias after surgery.

METHODS

We retrospectively investigated 89 consecutive patients who were diagnosed to have double-chambered right ventricle and underwent a surgical intervention from 1995 to 2016. The data obtained by echocardiography, cardiac catheterisation, and surgical findings as well as post-operative follow-up, surgical approaches, post-operative morbidity, mortality, and cardiac events were evaluated.

RESULTS

Median age at the time of diagnosis was 2 months and mean age at the time of operation was 5.3 years. Concomitant cardiac anomalies were as follows: perimembranous ventricular septal defect (78 patients), atrial septal defect (9 patients), discrete subaortic membrane (32 patients), right aortic arch (3 patients), aortic valve prolapse and/or mild aortic regurgitation (14 patients), and left superior caval vein (2 patients). The mean follow-up period was 4.86 ± 4.6 years. In these patients, mean systolic pressure gradient in the right ventricle by echocardiography before, immediately, and long-term after surgical intervention was 66.3, 11.8, and 10.4 mmHg, respectively. There were no deaths during the long-term follow-up period. Surgical reinterventions were performed for residual ventricular septal defect (2), residual pulmonary stenosis (1), and severe tricuspid insufficiency (1).

CONCLUSION

The surgical outcomes and prognosis of double-chambered right ventricle are favourable, recurrence and fatal arrhythmias are unlikely in long-term follow-up.

Giant right atrium and subvalvular pulmonary stenosis: A case report of an interesting combination

A 20-year-old Congolese woman presented with presyncope, dyspnea, and anasarca. Past medical history was unremarkable. Echocardiography revealed a rare combination of giant right atrium (RA), a dilated and hypertrophied right ventricle, subvalvular pulmonary stenosis (subPS), severe tricuspid regurgitation (TR), pericardial effusion and what appeared to be a spontaneously closed ventricular septal defect (VSD). Cardiac Magnetic Resonance and Cardiac Computed Tomography confirmed the findings excluding the presence of intra-cardiac and extra-cardiac shunt and other associated congenital anomalies. The patient underwent subPS resection, right atrioplasty, and tricuspid annuloplasty. Multimodality approach facilitated the detection of the abnormalities and provided clarity when determining the optimal surgical strategy.

An (In)Significant Ventricular Septal Defect and/or Double-Chambered Right Ventricle: Are There Any Differences in Diagnosis and Prognosis in Adult Patients

A double-chambered right ventricle (DCRV) is an uncommon congenital anomaly: the right ventricle (RV) is divided into two chambers due to the presence of an abnormally located muscular band or anomalous muscle hypertrophy in the subinfundibular part of RV outflow tract, with a variable degree of obstruction. Generally, DCRV is well recognized in childhood and misdiagnosed in adult patients. Transthoracic and/or transesophageal echocardiography are the mx0435;thods of choice for the diagnosis of DCRV. Due to limitations of echocardiography in adult patients, this entity may be missed, particularly if it presents concomitant with other congenital defects, and therefore additional imaging methods such as MRI or cardiac catheterization are required for a definitive diagnosis.

Double chambered right ventricle with ventricular septal defect in adults: case series and review of the literature

Double-chambered right ventricle (DCRV) is an uncommon congenital anomaly in which anomalous muscle bands divide the right ventricle into two chambers; a proximal high-pressure and distal low-pressure chamber. It may be associated with mid right ventricular obstruction. It is commonly associated with other congenital anomalies, most frequently perimembranous ventricular septal defect (PM-VSD). We herein present 5 adult patients with concomitant DCRV and PM-VSD who varied in their symptomatic presentations and the ways of management.

Ventricular septal defect and double-chambered right ventricle in an alpaca

A 20-month-old male alpaca was referred for evaluation of a cardiac murmur evident since birth. Echocardiography identified a ventricular septal defect (VSD) and a fibro-muscular band causing a stenosis of the right ventricular outflow tract. Right ventricular catheterization and selective angiography confirmed the diagnosis of VSD and double-chambered right ventricle with bidirectional shunting.

Ventricular septal defect and bidirectional shunting? Things are not what they seem

This report describes the case of a 19-year-old woman with a diagnosis of muscular ventricular septal defect. Bidirectional shunting was observed during a transthorathic echocardiography evaluation which also suggested normal pulmonary arterial pressure. Moreover, anomalous and hypertrophic right ventricular muscular bands were observed. After having ruled out other possibilities, the plausible explanation is one, which is not described in the literature. The findings may be explained as a sequestrated portion of the cavity of the right ventricle that remains isolated from the rest of the right ventricle (RV) by anomalous and hypertrophic right ventricular muscular bands, with communication only between the left ventricle and the sequestrated part of the RV. This is an unusual variant of two-chambered RV simulating two-chambered left ventricle.

Outcomes of surgical repair of double-chambered right ventricle

BACKGROUND

We reviewed our experience with surgical repair of double-chambered right ventricle and long-term outcome.

METHODS

From November 1970 to February 2008, repair of double-chambered right ventricle was performed in 61 patients (31 males). The median age was 13 years (interquartile range, 2 months to 64 years); 10 patients were infants (16%). Mean preoperative right ventricular outflow tract pressure gradient was 67±37 mm Hg. An associated ventricular septal defect was present in 50 patients (82%).

RESULTS

There were 2 (3%) early deaths due to persistence of low cardiac output postoperatively, despite complete relief of the right ventricular gradient. The overall mean postoperative gradient was 2±4.5 mm Hg. Late follow-up was complete in 92% (mean, 7.4±7.9 years; maximum, 37 years). Late survival was 90% at 10 years. There were 3 late deaths due to heart failure in 2 patients and sudden death in 1 patient, all occurring before 1997. No patients required reoperation for residual or recurrent right ventricular obstruction.

CONCLUSIONS

Surgical correction of double-chambered right ventricle results in excellent functional and hemodynamic long-term results, with complete relief of the right ventricular obstruction. The presence of a double-chambered right ventricle should be considered in anomalies with high or persistent right ventricular outflow tract obstruction.

Natural internal banding in adult patients with a large ventricular septal defect and a preserved pulmonary vascular system

OBJECTIVE

Hypertrophied anomalous muscle bands (AMBs) in the right ventricular outflow tract (RVOT) may develop in the context of ventricular septal defects (VSDs) and limit persistent pulmonary overflow. In adult patients with a large VSD, persistent AMBs in the RVOT therefore can simulate the role of an externally placed pulmonary artery band. We termed such alterations natural internal bands (NIBs). Our goal was to establish the morphologic nature of the obstructive muscular lesions of the RVOT in patients with a large VSD.

METHODS

Patients who underwent operations for a large VSD in our center, which has a high volume of adult patients with congenital defects, were retrospectively reviewed, and the nature of the NIBs in these patients was documented. All patients underwent transthoracic echocardiography and cardiac catheterization evaluations preoperatively and at postoperative month 3. Histopathologic examination of the AMBs was performed.

RESULTS

Of 96 adult patients who underwent operations for a large isolated VSD (mean defect size, 16.9 ± 3.5 mm), 16 patients had a hemodynamically significant NIB. Two different patterns of obstruction were found. Ten of the 16 patients revealed an os infundibulum morphology, and 6 patients revealed systolic bulging of the conal septum. Four of the patients with os infundibulum also had classic tetralogy-type septal malalignment. The mean peak systolic gradient on the RVOT was 56.5 ± 17.2 mm Hg and 53.6 ± 12.3 mm Hg in the patients with os infundibulum and in the patients with systolic bulging of the conal septum, respectively. Surgical repair of the VSD was completed successfully in all patients. Resection of the os infundibulum was performed concomitantly in patients with os infundibulum. At the third postoperative month, the mean peak systolic gradient was 16.8 ± 3.5 mm Hg in patients with os infundibulum and 26 ± 5.9 mm Hg (range, 20-35 mm Hg) in patients with systolic septal bulging.

CONCLUSIONS

Some mechanisms in adult type VSDs are essential for protecting the pulmonary vasculature. We tried to review these protective mechanisms: hypertrophied AMBs and NIBs.

Intravascular ultrasound catheter for transesophageal echocardiography in congenital heart surgery -A case report-

Transesophageal echocardiography (TEE) has an important role during congenital heart surgery. TEE in small infants is associated with complications, including an inability to pass the TEE probe, esophageal trauma, airway compression, aortic compression, and interference with ventilation. Recently, a monoplane intravascular ultrasound catheter (IVUC) has been developed for intracardiac echocardiography. The efficacy of IVUC for transesophageal use has been shown in numerous animal studies and several human studies, but there have been few reports involving small infants using an IVUC probe. We examined 15 pediatric patients undergoing congenital cardiac surgery using an 8-Fr AcuNav IVUC probe. We checked the cardiac anatomy, cardiac function pre-operatively and de-aeration before weaning from CPB; the surgical repairs were evaluated post-operatively. Although the IVUC probe has limitations associated with the monoplane, we found the IVUC probe to be useful in small infants and safer than the TEE.

Initial clinical manifestations and mid- and long-term results after surgical repair of double-chambered right ventricle in children and adults

OBJECTIVE

By means of retrospective analysis of our institutional experience, we reviewed the clinical manifestation and outcomes of patients subsequent to surgical repair of double-chambered right ventricle.

METHODS

Between 1988 and 2005, we performed surgical repair in 35 of 37 patients diagnosed with double-chambered right ventricle. The patients ranged in age from 4 to 69 years, with a mean of 21.3 years. Most presented in infancy, with initial manifestation of a short systolic murmur in 34 (92%) of all cases. Pressure gradients were measured invasively across the right ventricular outflow tract of between 30 and 140 mmHg, with a median of 60 mmHg. An associated ventricular septal defect was present in 26 patients (70%). Of the group, 4 patients were aged over 40 years, and 2 had previously undergone operative closure of a ventricular septal defect.

RESULTS

The operative interval ranged from 2 months to 41 years, with a median of 9 years. In all, we resected muscular bundles and enlarged the right ventricular outflow tract. There was no hospital or late death. Median follow-up subsequent to surgery was 7 years, with a range from 0.4 to 11 years. No patient required further surgery to relieve any obstruction of the right ventricular outflow tract, nor long term medical therapy or pacing because of cardiac arrhythmia.

CONCLUSIONS

Surgical repair of a double-chambered right ventricle yields excellent haemodynamic and functional results over the mid to long term.

Rapid progression of midventricular obstruction in adults with double-chambered right ventricle

OBJECTIVE

The purpose of this study was to determine the rate of progression of midventricular obstruction in adolescents and adults with double-chambered right ventricle.

METHODS

Clinical and echocardiographic findings in 45 patients (mean age 26 +/- 6 years, range 15-44) diagnosed with double-chambered right ventricle were retrospectively analyzed. Twenty patients underwent surgical repair before the age of 15 years. The relationship between Doppler midventricular pressure gradient and patient age was analyzed in 25 patients without previous repair. Sequential change in midventricular obstruction was determined for patients with 2 or more Doppler echocardiographic examinations performed within at least a 2-year interval.

RESULTS

Right midventricular pressure gradient in nonrepaired patients was 70 +/- 38 mm Hg (range 25-150). A significant relationship between midventricular obstruction and patient age (r = 0.64, P <.001) was found. Midventricular pressure gradient at initial evaluation was 32 +/- 27 mm Hg in 16 patients < 25 years and 73 +/- 45 mm Hg in 9 patients >/= 25 years (P <.03). After the initial study, 5 patients underwent surgical repair and 13 patients without repair were followed up for a period of 6.1 +/- 2.7 years (range 2-9), in which midventricular pressure gradient increased from 32 +/- 26 mm Hg to 67 +/- 35 mm Hg (P <.001). The slope of the change in midventricular pressure gradient was 6.2 +/- 3 mm Hg per year of follow-up. Seven more patients underwent surgical repair during follow-up due to progression of the obstruction. There was no mortality nor residual midventricular obstruction in surgically repaired patients.

CONCLUSIONS

Mild right midventricular obstruction shows a fast rate of progression in adolescents and young adults. Thus, close clinical and echocardiographic follow-up is advised, and surgical repair should be considered if significant progression of obstruction is detected.

Types of obstructions in double-chambered right ventricle: mid-term results

BACKGROUND

The double-chambered right ventricle (DCRV) is increasingly recognized as a distinct obstruction entity. The nature of the obstruction is not well defined.

METHODS

Patients with DCRV were prospectively studied during the last 4 years according to the following criteria: 1) pressure gradient by echo Doppler and cardiac catheterization within the right ventricle; 2) angiographic demonstration, and 3) surgical confirmation.

RESULTS

From March 1997 to March 2001, 10 new cases were included. Age ranged from 2 to 14 years (mean 9.5 +/- 4.4 years), weight ranged from 9.9 to 75 kg (mean 23 +/- 13.6 kg), and height from 0.85 to 1.48 m (mean 114 +/- 19 cm). Systolic gradient by echo Doppler ranged from 20 to 135 mmHg (mean 86 +/- 44 mmHg) and by cardiac catheterization, 18 to 130 mmHg (mean 78 +/- 35 mmHg). In terms of angiographic findings, in six patients the right ventriculogram showed an oblique and low obstruction; in four patients the obstruction was high and horizontal. With regard to surgical findings, angiographic findings were confirmed by the surgeon except in one patient, in whom both types of obstruction were present. No mortality was observed. With follow-up 4 to 40 months after surgery (mean 24 +/- 15 months), 8 of 10 patients were evaluated; all corresponded to class I NYHA. Systolic gradient by echo Doppler ranged from 0 to 11 mmHg (mean 4 +/- 6 mmHg).

CONCLUSIONS

DCRV IS PRODUCED BY THE FOLLOWING THREE TYPES OF MUSCULAR OBSTRUCTIONS: low and oblique obstruction; high and horizontal obstruction, and mixed obstruction. Mid-term surgical results are satisfactory.

Repair of double-chambered right ventricle: surgical results and long-term follow-up

BACKGROUND

We reviewed the outcomes of double-chambered right ventricle repair.

METHODS

Between 1969 and 1998, 40 patients underwent surgical repair of a double-chamber right ventricle. The patients ranged in age from 3 months to 52 years (mean, 12.8 +/- 11.6 years). Right ventricular outflow tract pressure gradients were from 20 to 170 mm Hg (mean, 65.0 +/- 38.5 mm Hg) An associated ventricular septal defect was present in 27 patients (67.5%). Four patients were older than 30 years of age.

RESULTS

There were no hospital or late deaths. Mean postsurgical follow-up was 16.5 +/- 8.9 years (range, 2.5 to 31 years). No patient required further surgery to relieve obstruction of right ventricular outflow tract.

CONCLUSIONS

Surgical repair of a double-chambered right ventricle yields excellent hemodynamic and functional results over both the short and long term.

Double-chambered right ventricle presenting in adulthood

BACKGROUND

Double-chambered right ventricle is a form of right ventricular outflow tract obstruction that develops over time, often in patients with an abnormally short distance between the moderator band and pulmonary valve. This lesion typically presents in childhood or adolescence and is often accompanied by a ventricular septal defect. Only a handful of previous cases have been described in which double-chambered right ventricle occurred in adulthood.

METHODS

Since 1992, three patients more than 30 years old (38, 43, and 66 years of age) have presented at our institution with unusual symptoms or a previous incorrect diagnosis. We reviewed the clinical data in these patients.

RESULTS

Presenting symptoms included syncope, angina, and severe dyspnea resembling pulmonary hypertension. In 1 patient, disease was categorized as New York Heart Association class IV, and in the other 2 as class III. Coexisting anomalies included a patent foramen ovale or secundum atrial septal defect in 2 patients, a small ventricular septal defect in 1 (with a probable history of ventricular septal defect in another), and mild aortic regurgitation in 1. All patients required urgent or emergent operations, with peak pressures in the proximal right ventricular chamber of 135 to 180 mm Hg and severely depressed left ventricular function in 1 patient. Resection of the anomalous right ventricular muscle bundles was achieved through a right atrial approach in all patients. All patients were alive with improved functional status at follow-up, which was between 15 and 40 months.

CONCLUSIONS

Right ventricular outflow tract obstruction resulting from a double-chambered right ventricle is rare in adults, but when it does occur it can present with unusual symptoms. When evaluating the patient with signs or symptoms of primary right heart failure, cardiologists should make an effort to image the entire right heart complex. Subcostal echocardiography can facilitate adequate visualization of the right ventricle when it is difficult to distinguish the subpulmonary outflow tract from the parasternal and apical windows.

Membranous subpulmonic stenosis associated with ventricular septal defect and aortic insufficiency

We present a case report of a patient with conal septal hypoplasia (supracristal) ventricular septal defect (VSD) complicated by aortic insufficiency (AI) and subpulmonic stenosis from a fibrous membrane. The development of AI with VSD is a well-recognized problem. However, the association of VSD, AI, and significant right ventricular outflow tract obstruction (RVOTO) is less common. Mechanisms of RVOTO include prolapse of an aortic valve cusp across the VSD, as well as infundibular hypertrophy or muscle bundles. Technical echocardiographic issues can make the diagnosis of VSD, AI, and RVOTO challenging. The presence of a discrete fibrous subpulmonary membrane is uncommon in this setting.

The nature of the obstructive muscular bundles in double-chambered right ventricle

OBJECTIVE

Our goal was to establish the morphologic nature of the obstructive muscular lesions in double-chambered right ventricle.

METHODS

We based our morphologic observations on 10 normal hearts and on the surgical findings in 26 patients, aged 0.5 to 24 years, with a mean of 6.9 years (SD 5.8 years). In the normal hearts, we measured the distance from the pulmonary valve to the apex of the right ventricle and from the takeoff of the moderator band to the ventricular apex. From angiograms available in 20 patients, using the frontal view, we then measured the distance from the pulmonary valve to the apex of the right ventricle and from the midpoint of the obstructive lesion to the apex of the right ventricle. This permitted calculations of multiple ratios.

RESULTS

In the 10 normal hearts, the moderator band took origin at a mean ratio of 0.48 (SD 0.16) of the ventricular length. On the basis of the angiographic findings, we identified 2 basic forms of double-chambered right ventricle. In 9 patients, the obstructive muscular shelf was positioned low and diagonally across the apical component, with a mean ratio of 0.38 relative to the ventricular length (SD 0.02). In the other 11 patients, the obstructive shelf was high and horizontal, with a mean ratio of 0.27 (SD 0.02). The difference was statistically significant (P =.001). Surgical repair was performed successfully in all 26 patients through a right ventriculotomy.

CONCLUSIONS

Double-chambered right ventricle is the consequence of a high or low muscular division of the apical component of the right ventricle. The abnormal muscular bundle probably represents accentuated septoparietal trabeculations, rather than always being an abnormal moderator band.

Rare variants of divided right ventricle with sequestered apical trabecular component

The right ventricle may be divided into two or more compartments by various structures in various ways. Rarely, the apical trabecular component may be sequestered from the rest of the right ventricle. We report 4 cases with different underlying lesions that share a common pathology of apical sequestration of the right ventricle resulting in diverse hemodynamic consequences. Case 1 had pulmonary valve stenosis. The apical sequestration of the right ventricle resulted in no significant hemodynamic consequence. Case 2 had multiple defects in the muscular ventricular septum. The volume of left-to-right shunt seemed to be reduced because of the commitment of some of the defects to the sequestered cavity. Case 3 had a large defect in the trabecular septum. As the defect involved the whole septum that was related to the sequestered right ventricular apex, the left ventricle together with the sequestered right ventricle formed a boot-shaped chamber. Hemodynamically, the muscular shelf was an interventricular septum. Case 4 had a coronary artery fistula to an isolated cavity that occupied the apical region of the right ventricle. The pathology was similar to the case that was reported as a five-chambered heart. The abnormal cavity was, in fact, the sequestered right ventricular apex.

Double-chambered right ventricle: echocardiographic features

Double-chambered right ventricle is an uncommon congenital heart disease, studied mostly by angiography, characterized by the division of the right ventricular cavity into two different pressure chambers. To analyze the anatomic features of this disease, data from 13 patients examined by echocardiography at the Mayo Clinic were reviewed. Despite the anatomic variety of this abnormality, two main types were identified. In the first type, intraventricular obstruction was due to an anomalous muscle bundle crossing the right ventricular cavity from the interventricular septum to the parietal wall. In the second type, no anomalous bundles were identified, and interventricular obstruction was due to marked parietal and septal hypertrophy. The main interventricular gradient was higher in the first type, and a ventricular septal defect was found to be associated more commonly with the second type.

Malalignment-type ventricular septal defect in double-chambered right ventricle

Double-chambered right ventricle (DCRV) is commonly associated with ventricular septal defect (VSD). In this study, an assessment was made of the relevance of a malalignment-type VSD to hemodynamic and morphologic features in DCRV. During an 8.5-year period, 53 patients with DCRV were enrolled after study with echocardiography, catheterization, and angiography. Patients were divided into 2 groups: group I included 40 patients, aged 3.7 +/- 3.2 years, with a malalignment-type VSD; group II consisted of 13 patients, aged 8.6 +/- 2.7 years, without a malalignment-type VSD. History of congestive heart failure in infancy was present in 21 group I and 2 group II patients (53% vs 15%, respectively, p <0.05). The mean pulmonary-to-systemic flow ratio was significantly higher in group I than in group II (1.89 +/- 0.74 vs 1.14 +/- 0.21, respectively, p <0.05). The mean pressure gradient across the right ventricular outflow tract was lower in group I than in group II (41 +/- 16 vs, 73 +/- 33 mm Hg, respectively, p <0.05). Among 42 patients who had a series of echocardiograms recorded, progression of pressure gradient was evident in 35: 28 in group I and 7 in group II. A subaortic ridge was present exclusively in 29 group I patients (73%). Prolapse of the aortic valve was present in 26 (49%): 20 group I (50%) and 6 group II (46%) patients. Aneurysm formation of the septal defect was found in 17 (43%) and 7 (54%) group I and II patients, respectively. It can be concluded that a history of congestive heart failure was more common in DCRV patients with a malalignment-type VSD. Malalignment-type VSD is significantly associated with a larger pulmonary-to-systemic flow ratio and subaortic ridge.

Implication of anterior septal malalignment in isolated ventricular septal defect

OBJECTIVE

The aim was to define the long term prognosis of isolated ventricular septal defect (VSD) with anteriorly malaligned outlet septum.

DESIGN

Cohort study.

SETTING

University hospital, tertiary medical care centre.

PATIENTS

Between July 1986 and June 1993, 63 patients were studied with an isolated VSD and anteriorly malaligned outlet septum (59 perimembranous; 4 muscular outlet).

MAIN OUTCOME MEASURES

The diagnosis of septal malalignment, aneurysmal transformation, right ventricular obstruction, subaortic ridge, and aortic valve prolapse was based on echocardiographic criteria, then confirmed by angiography in 33 patients and by surgery in 28. An actuarial curve for each event was obtained by Kaplan-Meier non-parametric analysis and the significance was examined by log-rank test.

RESULTS

Aneurysmal transformation decreased the size of the VSD in 52% of the patients, but was also associated with the appearance of subaortic ridge (p < 0.05). Progressive obstruction in the right ventricle was observed in 51%, more often in those without aneurysmal transformation (p < 0.05). Aortic valve prolapse was quite common whether or not aneurysmal transformation occurred (33% and 23%, respectively). This was attributed to the location of the VSD and the anterior malalignment of the outlet septum. Surgery was performed in 28 patients at a median age of 50 months because of significant left to right shunt (n = 5), or the development of obstruction in right ventricle (n = 9), aortic valve prolapse (n = 3), or combinations (n = 11). The presence of subaortic ridge per se was not considered to be a surgical indication.

CONCLUSIONS

Anteriorly malaligned VSDs have variable presentation. Careful echocardiographic evaluation is needed to identify various combinations of progressive right ventricular obstruction, aneurysmal transformation, subaortic ridge, or aortic valve prolapse. In extreme cases a patient may have a pathology complex comprising right ventricular outflow obstruction, subaortic ridge, aortic valve prolapse, and anteriorly malaligned VSD.

Double-chambered right ventricle: experience with 52 cases

The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and outflow portions of the right ventricle, thus resulting in double-chambered right ventricle bearing troublesome clinically in its diagnosis. The aim of the present study was to review the diagnostic criteria. Fifty-two patients with a double-chambered right ventricle were seen during an 8-year period. They ranged in age at the catheterization from 4 months to 17 years (mean 7.5 +/- 4.4 years). Diagnosis was confirmed in 51 patients at cardiac catheterization and in other one on operation. The majority of the patients had associated cardiac anomalies: there were 33 ventricular septal defect (63%), 21 pulmonary valve stenosis (40%), nine atrial septal defect (17%), and four double-outlet right ventricle. The electrocardiograms revealed upright T waves alone in right precordial leads suggesting right ventricular hypertrophy in 33% of the patients. At cardiac catheterization, there was a pressure gradient of 20-160 mmHg between the right ventricular inflow and outflow portions. Forty patients have had surgery and four have undergone balloon pulmonary valvuloplasty. Surgical treatment was planned for two patients and other six had no indication for treatment.

Intra-utero diagnosis of anomalous right ventricular muscle bundles in association with a ventricular septal defect: a case report

The morphology and natural history of anomalous right ventricular muscle bundles (ARVMB) have been described in a number of postnatal studies. Whether this is a congenital or acquired cardiac lesion remains obscure. A fetal echocardiogram performed in a 32-week gestation mother showed a large ventricular septal defect and anomalous right ventricular muscle bundles, which were easily appreciated at the ostium-infundibular level. The diagnosis was confirmed postnatally and at 6 months of age the child underwent surgical repair. This report documents the presence of ARVMB in a fetus, at a time when hemodynamics cannot explain the development of right ventricular muscle bundles. It suggests that at least, the morphologic substrate for this disease is congenital.

Color flow Doppler in the diagnosis of double-chambered right ventricle: a demographic and echocardiographic study

The purpose of this study was to evaluate the demographic and echocardiographic data of patients diagnosed with double-chambered right ventricle and attempt to explain a perceived rise in the incidence.

DEFINITION

Double-chambered right ventricle (DCRV) is a division of the right ventricle into two chambers by a hypertrophied muscle bundle.

METHODS

The medical records of patients diagnosed with DCRV were reviewed, and demographic, echocardiographic, and catheterization data were tabulated. Annual incidence of DCRV, based on year of birth, was compared to yearly detection rate, based on year of DCRV diagnosis. To evaluate the influence of color flow Doppler on the frequency of diagnosis of DCRV, demographics of patients born prior to September 1986 (when utilization of color Doppler began in our institution) were compared to those born after that date.

RESULTS

Despite an unchanged annual incidence of DCRV, yearly detection rate of this lesion rose significantly following the introduction of color flow Doppler to our institution (September 1986). DCRV was diagnosed earlier and was accompanied by earlier catheterization, which also showed lower right ventricular body gradients after September 1986. Associated anomalies, both cardiac and noncardiac, in our population differed from those reported in previous series.

CONCLUSION

This study infers that the advent of color flow Doppler significantly enhanced the diagnosis of DCRV in our pediatric patients and led to a perceived rise in incidence.

Pulmonary valve-moderator band distance and association with development of double-chambered right ventricle

Double-chambered right ventricle (DCRV), a form of right ventricular outflow obstruction that sometimes accompanies a ventricular septal defect (VSD), is associated with superior and rightward displacement of the septal insertion of the moderator band. It was hypothesized that this superior displacement is present and identifiable by echocardiography in patients with a VSD even before right ventricular outflow tract obstruction develops. Eight patients who had a previous echocardiographic study showing a VSD alone were echocardiographically diagnosed as having DCRV. Their initial echocardiographic studies were reviewed, and superior displacement of the moderator band was quantified by measuring the distance between the pulmonary valve and moderator band, normalized to tricuspid anulus diameter. These measurements were compared with those from the initial studies of the following 3 other groups: (1) an age-matched group of 10 patients with no structural heart disease; (2) an age-matched group of 10 patients with a VSD who did not develop DCRV; and (3) a group (not age-matched) of 10 patients with VSD and DCRV in whom subpulmonary obstruction was present on the initial study. The 8 patients who eventually developed subpulmonary obstruction had significant superior displacement of the moderator band at the time of their initial echocardiogram compared with that of the 2 age-matched control groups (p less than 0.01). In contrast, there was no significant difference in moderator band displacement between these patients and the 10 with DCRV who already had right ventricular outflow obstruction at their initial study (p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Transatrial repair of double-chambered right ventricle

Seventeen consecutive patients with double-chambered right ventricles underwent intracardiac repair from February, 1985 through March, 1989. Nine patients had an associated ventricular septal defect. A transatrial approach to the repair was utilized in all patients. Early postoperative right ventricular-to-left ventricular pressure ratio was a mean of 0.29, range 0.21 to 0.37. There were no hospital or late deaths. We conclude that transatrial repair of a double-chambered right ventricle can be accomplished routinely with satisfactory results.

An echocardiographic study of the association of ventricular septal defect and right ventricular muscle bundles with a fixed subaortic abnormality

Since 1983, 36 patients with the combination of right ventricular muscle bundles and a perimembranous ventricular septal defect have been studied in our institution to address the incidence of on associated subaortic abnormality. Of that total 32 (88%) had echocardiographic evidence of such an abnormality (29 had a typical subarotic ridge protruding from the crest of the interventricular septum and the remaining 3 had an echodense area in the same location). Surgical confirmation of the presence or absence of a subaortic abnormality was available in 26. There was correlation between the surgical and echocardiographic findings in all patients. A resting Doppler gradient of greater than or equal to 10 mm Hg was present in only 10. During the study period, 6 patients had Doppler evidence of progression of their gradient. The incidence of subaortic abnormalities in right ventricular muscle bundles and ventricular septal defects appears to be far greater than previously suspected. The exact significance of this finding in the absence of a pressure gradient is still unclear.

Double-chambered right ventricle

Thirty (10.8%) of 279 patients undergoing correction of a ventricular septal defect (VSD) from January, 1972, to September, 1986, also had a double-chambered right ventricle (DCRV). Age at operation ranged from 1.3 to 18.8 years (mean, 6.7 +/- 4.5 years [+/- standard deviation]). Seventeen patients were male, and 13 were female. Two-dimensional echocardiography was used after 1978 in the initial evaluation of 20 patients; however, the diagnosis of DCRV was made with the use of subcostal views only since 1984 in 4 of 5 patients. Surgical correction consisted of closure of the VSD and resection of anomalous muscle bundles through a right ventriculotomy (28 patients), and right atriotomy (2 patients). All patients survived and are asymptomatic 4.2 +/- 3.4 years following operation. Six patients have undergone catheterization postoperatively and 8 patients had intraoperative pressure recordings. The mean preoperative ratio of right ventricular to left ventricular pressures was 0.67 +/- 0.22 compared with 0.34 +/- 0.15 postoperatively (p less than .001). In 2 patients, DCRV was not recognized preoperatively or at VSD closure through a right atriotomy, and reoperation was necessary after DCRV was demonstrated at postoperative catheterization. DCRV may occur in approximately 10% of patients undergoing correction of VSD. Careful evaluation of echocardiographic and catheterization data preoperatively and careful evaluation of the anatomy intraoperatively are necessary so that DCRV not be overlooked, especially because most VSDs are now closed through the right atrium. Successful correction of VSD and DCRV is associated with excellent long-term results.

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.