A rare complication of aortic valve endocarditis: diagnosis with transesophageal echocardiography

The mirror image of Gerbode defect: acquired right ventricular-to-left atrial communication

: Left ventricular-to-right atrial communication, known as Gerbode defect, is rare. However, right ventricular-to-left atrial communication is much rarer. We present a case of a middle-aged woman with a past history of primum atrial septal defect surgery who presented with dyspnea on exertion. Echocardiographic studies showed dehiscence of the pericardial atrial patch from atrioventricular junction, causing a right ventricular-to-left atrial communication with bidirectional shunt. A three-dimensional transesophageal echocardiographic reconstruction revealed a defect of septal tricuspid valve leaflet. In atrioventricular septal defect, the apical displacement of mitral valve insertion, together with a congenital defect of septal tricuspid valve leaflet, contributes to predisposing conditions for this communication.

Acquired Gerbode defect following endocarditis of the tricuspid valve: a case report and literature review

The Gerbode’s defect is a communication between the left ventricle and right atrium. It is usually congenital, but rarely is acquired, as a complication of endocarditis, myocardial infarction, trauma, or after previous cardiac surgery. The acquired Gerbode defect with involvement of the tricuspid valve acquired after bacterial endocarditis can be challenging to repair. We present a rare case of young woman, with endocarditis of the tricuspid valve and acquired Gerbode defect without previous cardiac surgery. She underwent successful surgical closure of the Gerbode defect and reconstruction of the septal leaflet of the tricuspid valve using a an autologous pericardial patch. A total of 20 other cases were reported with acquired Gerbode defect due to endocarditis in patients without previous cardiac surgery. Three other cases presented acquired Gerbode defect due to myocardial infarction and two due to chest trauma. Another series of 62 patients presented acquired Gerbode defect after previous cardiac surgery. Surgical treatment is always feasible with excellent outcome. However the percutanous transcatheter closure remains an excellent option especially in high risk patients.

Acquired left ventricle-to-right atrium shunt: clinical implications and diagnostic dilemmas

BACKGROUND

The acquired left ventricle-to-right atrium (LV-RA) shunt (Gerbode defect) is rare but it can sometimes be a critical condition. The diagnosis is quite challenging largely due to its exotic anatomic features and diagnostic difficulties. This study aims to present the clinical features and diagnostic solutions of this rare lesion.

METHODS

Data source was based on a comprehensive literature retrieval of acquired LV-RA shunts of 1990-2014.

RESULTS

Most of the acquired LV-RA shunts are of either a postoperative or an infective etiology. Transthoracic echocardiography showed a 62.2% accurate diagnosis, 13.4% inclusive diagnosis, 9.8% missed diagnosis, and 14.5% misdiagnosis rate. The accurate diagnostic rate of transthoracic echocardiography was significantly lower than that of the transesophageal echocardiography or cardiac catheterization. The LV-RA shunts are often misinterpreted as mitral regurgitation, pulmonary hypertension, tricuspid regurgitation, Valsalva aneurysm rupture, and subaortic/high perimembrane/residual ventricular septal defect. Surgical, interventional, and conservative treatments were applied in 57.8, 24.4, and 17.8% patients, respectively. Prognosis showed an event-free survival of 85%, a comorbidity of 9.1%, and a mortality of 13.6%.

CONCLUSIONS

A high jet detected in the right atrium with uncertain origin and course has to appeal to additional diagnostic techniques including transesophageal echocardiography, cardiac catheterization, or cardiac magnetic resonance imaging for differential diagnoses. Small restrictive shunts are preferred with conservative treatments, high-risk patients are candidates of interventional therapy, and the patients with unstable hemodynamics warrant an open heart surgery. Careful operative maneuver, good control of intracardiac infection, preservation of heart function, etc., are mandatory for the prevention of the development of an acquired LV-RA shunt.

Left ventricular to right atrial shunt (Gerbode defect): congenital versus acquired

Introduction

Congenital left ventricular to right atrial (LV-RA) shunt (Gerbode defect) is rare, while acquired LV-RA shunt has been increasingly reported. As yet, systematically incorporated data of the LV-RA shunt have not been presented.

Aim

To present the clinical features, diagnostic challenge and management strategies of congenital and acquired LV-RA shunts.

Material and methods

The data source was based on a comprehensive literature retrieval of the LV-RA shunt in the period 1990–2013.

Results

In comparison with the acquired Gerbode defect, the congenital Gerbode defect group of patients were younger and were associated more often with additional congenital disorders. Previous cardiac surgery and infective endocarditis were the two major aetiologies of the occurrence of the acquired shunts. Paravalvular abscess was associated in 10.2% and atrioventricular block in 13.6% of the acquired group patients. Transoesophageal echocardiography showed a higher diagnostic accuracy, lower missed diagnosis and lower inclusive diagnosis rates, in comparison to transthoracic echocardiography, but the misdiagnosis rates of the two modalities did not differ from each other. Four (4.5%) of the acquired group patients were complicated by atrioventricular block following surgical or interventional closure of the shunt. Eight (9.1%) patients died in the acquired group, but no patient died in the congenital group.

Conclusions

The diagnosis of an LV-RA shunt is quite challenging, especially in the context of coexisting abnormalities including an additional intracardiac shunt, tricuspid regurgitation, pulmonary artery hypertension and infective endocarditis, which have to be carefully differentiated from the shunt by further investigations. A better control of infective complications and careful manoeuvres during surgery may help to keep the LV-RA-sensitive septum intact.

Concomitant Gerbode-like defect and anterior mitral leaflet perforation after aortic valve replacement for endocarditis

We present a case of concomitant left ventricle (LV) to right atrial shunt (Gerbode-like defect) and anterior mitral leaflet perforation in a 32-year-old male after aortic valve replacement for infective endocarditis of bicuspid aortic valve. This case emphasises that intra-operative transesophageal echocardiography is a sine qua non for valvular surgical procedures.

Gerbode defect following endocarditis and misinterpreted as severe pulmonary arterial hypertension

A Gerbode-type defect is a ventricular septal defect communicating directly between the left ventricle and right atrium. It is usually congenital, but rarely is acquired, as a complication of endocarditis. This can be anatomically possible because the normal tricuspid valve is more apically displaced than the mitral valve. However, identification of an actual communication is often extremely difficult, so a careful and meticulous echocardiogram should be done in order to prevent echocardiographic misinterpretation of this defect as pulmonary arterial hypertension. The large systolic pressure gradient between the left ventricle and the right atrium would expectedly result in a high velocity systolic Doppler flow signal in right atrium and it can be sometimes mistakably diagnosed as tricuspid regurgitant jet simulating pulmonary arterial hypertension. We present a rare case of young woman, with endocarditis who presented with severe pulmonary arterial hypertension. The preoperative diagnosis of left ventricle to right atrial communication (acquired Gerbode defect) was suspected initially by echocardiogram and confirmed at the time of the surgery. A point of interest, apart from the diagnostic problem, was the explanation for its mechanism and presentation. The probability of a bacterial etiology of the defect is high in this case.

Ventricular septal defect with secondary left ventricular-to-right atrial shunt is associated with a higher risk for infective endocarditis and a lower late chance of closure

OBJECTIVE

Although ventricular septal aneurysm may diminish or even close the shunt through the ventricular septal defect (VSD), developing a left ventricular-to-right atrial (LV-RA) shunt may be unfavorable. This study sought to clarify this issue on the basis of an extended observation of such patients.

METHODS

Sixty-eight patients (1201 patient-years) who had small perimembranous VSD and LV-RA shunt and were not operated on before 6 years of age were studied.

RESULTS

The onset age of LV-RA shunt was 5.8 +/- 3.3 years, with clinical improvement later observed in 23 (34%). The murmur disappeared and showed spontaneous closure in 5 (7%). Seven episodes of infective endocarditis occurred in 6 (8.7%, or 58 per 10000 patient-years), with 2 receiving surgery. Another 4 received surgery during follow-up. With echocardiography, aneurysmal transformation involving the anterior and septal leaflets of tricuspid valve (double sac) was found in 56 (85%), whereas only the septal leaflet (single sac) was involved in 10. Patients with double sac were less likely to show improvement, whereas patients who had superior QRS axis and were female showed clinical improvement more frequently.

CONCLUSIONS

VSD with secondary LV-RA shunt is associated with a higher risk for infective endocarditis but still has a low chance for late improvement and even closure.

Imaging techniques for diagnosis of infective endocarditis

Cardiac imaging, specifically echocardiography, has greatly enhanced the ability of clinicians to effectively diagnose and manage IE. Echocardiograms should generally be obtained in all patients suspected of having IE, both to establish the diagnosis and to identify complicated cardiac involvement that may warrant surgical intervention. Transesophageal imaging is more sensitive and specific than the transthoracic approach and currently represents the optimal approach to echocardiographic imaging. Manifestations of endocardial involvement include vegetations, abscesses, aneurysms, fistulae, leaflet perforations, and valvular dehiscence. The roles of other imaging modalities including CT, MRI, and nuclear imaging have yet to be fully established.

Imaging techniques for diagnosis of infective endocarditis

With the ability to structurally characterize cardiac manifestations, echocardiography is used for the diagnosis and management of infective endocarditis. In establishing the diagnosis according to the Duke criteria, the findings of endocardial involvement (vegetation, abscess, prosthetic valve dehiscence) or new valvular regurgitation represent "major" diagnostic criteria. As echocardiography cannot reliably differentiate noninfective from infective lesions, however, proper diagnosis lies in correlating echocardiography with clinical findings. The more invasive transesophageal approach provides substantially greater image resolution; this approach should be considered first in the evaluation of patients with higher prior probabilities of endocarditis and those with potential endocardial complications.

Gerbode's defect associated with acute sinus node dysfunction as a complication of infective endocarditis

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