Prenatal diagnosis of membranous ventricular septal aneurysms and their association with absence of atrioventricular valve 'offsetting'

Prenatally Diagnosed Interventricular Septal Aneurysm with Associated Ventricular Dysfunction

Congenital interventricular septal aneurysms (IVSA) of the muscular septum are rare and can be associated with other familial abnormalities of the ventricular septum, arrhythmias, additional congenital heart disease, and chromosomal abnormalities. IVSA is also linked to ventricular dysfunction and non-compaction, although there are limited reports of this association presenting in utero. We describe a case of fetal ventricular septal aneurysm associated with ventricular dysfunction and pericardial effusion.

Autopsy and postnatal follow-up of prenatally diagnosed ventricular outpouchings

OBJECTIVES

Prenatal ventricular outpouchings (VOs), which include congenital ventricular aneurysms (CAs) and congenital ventricular diverticula (CD), are very rare. We describe the features and outcomes of prenatal VOs diagnosed over a 4-year period.

METHODS

Retrospective cohort study of cases of prenatal diagnoses of CAs and CD at our center between June 2014 and January 2018. The prenatal and postnatal echocardiogram data were reviewed, and telephone follow-up was conducted of liveborn cases.

RESULTS

A total of 25 VOs were identified. Two were lost to follow-up, 15 chose termination of pregnancy, and eight resulted in livebirths. Only two cases underwent autopsy: Histopathology showed that the CA wall was substituted by collagen fibers. At follow-up, none of the eight liveborn babies experienced adverse events, and three VOs near the tricuspid annulus almost disappeared, though one was extremely large.

CONCLUSIONS

In our center, all liveborn babies with VO had good prognoses. We hypothesize that VOs located near the right ventricular annulus may be caused by prenatally unbalanced pressure, given their decrease in size after birth when the right heart pressure declines.

Two Cases of Prenatally Diagnosed Membranous and Muscular Ventricular Septal Aneurysms

A ventricular septal aneurysm is a rare heart defect located in the muscular or membranous part of the septum. Muscular ventricular septal aneurysms are usually isolated, with a favorable prognosis. Membranous ventricular septal aneurysms are often associated with other heart anomalies, could result in serious complications, and may require surgical treatment. We describe 2 cases of prenatally diagnosed ventricular septal aneurysms: an isolated membranous ventricular septal aneurysm with a good outcome, which was initially misdiagnosed as an atrioventricular septal defect; and a muscular ventricular septal aneurysm associated with a hypoplastic aortic arch and severe hydrocephaly, which resulted in termination of the pregnancy. To our knowledge, the combination of a muscular ventricular septal aneurysm with an extracardiac anomaly has not been reported previously.

Interventricular Membranous Septal Aneurysm Incidentally Diagnosed During Computed Tomographic Angiography in a Patient with Infrequent Supraventricular Tachycardia

Interventricular membranous septal (IVMS) aneurysm is a rare condition with no accurate incidence. It is known to be associated with 0.3 % of congenital heart disease and 19 % of ventricular septal defects. IVMS aneurysm is often asymptomatic but can be complicated with right ventricular obstruction, rupture, thromboembolism, and conduction defects. Clinicians and radiologist should be aware about this rare clinical entity and evaluation of any possible underlying cardiac abnormalities should be performed. Conservative management with close follow up is the mainstay of management in the absence of complication.

Interventricular membranous septal aneurysm: CT and MR manifestations

Advanced cardiac imaging is a valuable method to investigate cardiac malformations. The detection of the interventricular membranous septum has clinical significance due to thrombogenic and arrythmogenic predisposition, as well as a role in obstructing the pulmonary flow. This review describes six clinical presentations in which advanced cardiac imaging has been the tool for evaluation, with special emphasis in CT angiography and cardiac MRI sequences.

Teaching Points

• The interventricular membranous septum can predispose patients to thrombogenic and arrythmogenic events.

• Subpulmonic stenosis relates to the protrusion of the aneurysm into the right ventricle

• During surgery, ventricular pressures of the opened heart become balanced, making the aneurysm less evident.

Electrophysiologic features of fetal ventricular aneurysms and diverticula

OBJECTIVE

Congenital ventricular wall defects are very rare and include congenital ventricular aneurysms (CVAs) and diverticula (CVDs).

METHOD

We report a series of five fetuses: three with CVAs and two with CVDs referred due to fetal arrhythmia. In addition to routine fetal echocardiography, fetal magnetocardiography (fMCG) was used. The literature in CVA and CVD is reviewed.

RESULTS

Incessant premature ventricular contractions (PVC), mainly bigeminy and trigeminy were found in three fetuses with CVAs and in one with CVD, who also had ventricular couplets. The other fetus with CVD, referred because of PVCs, had only sinus tachycardia. ST elevation was noted in two. Fetal movement had a variable impact on PVCs. Postnatal evaluation demonstrated two persistent left ventricular aneurysms and one persistent right CVD; one CVD resolved at 35-week gestation. Two neonates had incessant PVCs. Both arrhythmias resolved spontaneously while being treated with propranolol.

CONCLUSION

FMCG is complementary to echocardiographic imaging. In fetuses with left ventricular wall defects, additional electrophysiological diagnosis can be made by fMCG, including the complexity of ventricular ectopy, arrhythmic response to fetal movement, presence of ST-T wave abnormalities, and atrial amplitude increases. Prenatal risk factor assessment using fMCG can additionally support post-natal treatment and follow-up.

An incidentally detected giant membranous interventricular septal aneurysm secondary to previous surgery for subaortic valvular stenosis

Ventricular septal aneurysms are rare clinical entities and their certain prevalence and clinical significance are not well known. Most of them are thought to develop during or after the closure process of the accompanying ventricular septal defects. Although a majority of the patients are typically asymptomatic, the potential risks should also be kept in mind. We present a case of a membranous interventricular septal aneurysm that developed after surgery for subaortic valvular stenosis. The points that make our case worth reporting are development of the aneurysm after aortic surgery and lack of a concomitant ventricular septal defect. On the basis of the existence of an aortic valve surgery history and reports that do not mention any ventricular septal defect and ventricular septal aneurysm when she was operated, we suggest that the aneurysmatic formation in the membranous portion of the interventricular septum developed due to valve surgery in the postoperative wound healing period.

Magnetic resonance imaging of AMS (Aneurysm of the Membranous Septum), review of the literature and case report

Aneurysm of the Membranous Septum (AMS) is a rare cardiac disease, mostly associated with other cardiac anomalies, very rare in the absence of other congenital heart defects. A prompt diagnosis is important, due to severe potential complications, but remain challenging. Most of the cases were earlier diagnosed using ventriculography, but, with the availability of echocardiography and cardiovascular magnetic resonance (CMR), this disease can be accurately assessed non-invasively. We report a case of a 62 years old female patient, without other cardiac congenital disease, who was incidentally diagnosed, by means of CMR with a true and isolated AMS. Our report underlines CMR usefulness in AMS diagnosis, thanks to accurate evaluation (both morphologic and functional) provided by this diagnostic tool, which is able to demonstrate clearly the presence of AMS (aneurysm of the membranous septum) and depict its features.

Incidental discovery of a membranous ventricular septal aneurysm in two dissimilar patients

A ventricular septal aneurysm (VSA) is a rare cardiac anomaly, and an accurate statistic of its prevalence has not been reported in the literature. True incidence is likely underestimated as most patients are thought to be asymptomatic. As a result, most VSAs are discovered incidentally on echocardiography, during angiography, or at autopsy. Potential complications include rupture, bacterial endocarditis, right ventricular outflow tract obstruction, and thromboembolic disease. It has been proposed that VSAs occur in association with ventricular septal defects (VSDs) and other congenital cardiac abnormalities. It is uncommon for a VSA to exist in the absence of a known prior ventricular septal defect. We present two cases, each highlighting an incidental intact aneurysm involving the membranous interventricular septum. We discuss the contrast in the two patients with regard to their age, accompanying cardiac anomalies and cardiovascular fitness. Clinical implications of the condition are reviewed.

Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: clefts, aneurysms, diverticula and terminology problems

OBJECTIVES

Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center.

MATERIALS AND METHODS

Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities.

RESULTS

The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically significant difference was not detected between the sexes regarding LVC (P=0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal-apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected.

CONCLUSION

Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.

Atrioventricular block in an infant with an atrioventricular septal aneurysm

A case of atrioventricular (AV) septal aneurysm presenting in late fetal life with AV block is reported. In the neonatal period, second-degree AV block occurred, which progressed during infancy to complete block. This report includes ante- and postnatal echocardiograms demonstrating the anatomy. Only three other reports of AV septal aneurysm are found in the literature, none of which describe heart rhythm disturbance.

Pseudoaneurysm of the membranous septum, case report and review of the literature

Pseudoaneurysm (dissecting aneurysm) of the membranous septum is a rare occasion. Clinically, aneurysms and pseudoaneurysms not only have the potential to reduce ventricular size, but also can be further complicated by rupture of the aneurysm and by promoting tricuspid insufficiency, aortic valve prolapse, ventricular outflow tract obstruction, and bacterial endocarditis. We describe a case in which a pseudoaneurysm of the membranous septum was identified protruding into the left outflow tract.