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

Abstract

IntroductionCongenital 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.AimTo present the clinical features, diagnostic challenge and management strategies of congenital and acquired LV-RA shunts.Material and methodsThe data source was based on a comprehensive literature retrieval of the LV-RA shunt in the period 1990–2013.ResultsIn 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.ConclusionsThe 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.

Percutaneous closure of congenital Gerbode defect using Nit-Occlud® Lê VSD coil

“…The presence of normal diastolic pulmonary arterial pressure using pulmonic regurgitation jet is also very useful to distinguish the true pulmonary arterial hypertension from high velocity jet in the RA caused by Gerbode defect[ 4 , 5 ]. Actually, only about 2/3 of the LV-RA shunts of either congenital or acquired origin can be well diagnosed with TTE[ 6 ]. The 1/3 of others have to rely on other means like contrast echo, TEE, MRI, CTA or catheterization for accurate diagnosis.…”

Atrioventricular Shunt Post Acute Myocardial Infarction

“…In a recent large review of LV-RA shunts, 121 patients were identified in the literature; of those patients, 88 had acquired defects. 12 The etiologies of those acquired defects were postoperative (59%), infectious (28%), ischemic (5.7%), iatrogenic (4.5%), and traumatic (2.3%). Of the postoperative patients, 39 had valve surgery and 13 had surgery for congenital heart disease, five procedures of which were VSD repair.…”

Percutaneous repair of acquired Gerbode defect complicated by hemolysis and acute kidney injury

“…In a review of acquired Gerbode defects published from 1990 to 2013 [2], 59% were post-operative with 75% of these occurring post-heart valve surgery. If hemodynamically significant, they result in volume loading of both ventricles and may lead to heart failure.…”