ABSTRACT
The incomplete fusion of the septum primum and septum secundum results in the formation of the left atrial septal pouch (LASP). The clinical significance of this entity is a matter of controversy; however, it may act as a nidus for thrombus formation. We report a case of a 57-year-old male who was brought to the hospital by his girlfriend due to his bizarre behavior and confusion for one day. The initial workup for his altered mental status did not yield a diagnosis. The patient was admitted for further workup, which included an MRI of the brain that showed numerous very small-sized foci of restricted diffusion involving bilateral cerebral and cerebellar hemispheres consistent with thromboembolic infarct. The patient did not receive a tissue plasminogen activator (TPA) as he was out of the window for TPA. Transthoracic echocardiogram (TTE) with bubble study did not show patent foramen ovale (PFO) or atrial septal defect (ASD). ECG and telemetry showed normal sinus rhythm and no atrial fibrillation. A transesophageal echocardiogram (TEE) was obtained to find the source of the thromboembolic stroke. TEE discovered a 22 x 8-mm cystic structure in the interatrial septum consistent with a LASP. We hypothesize that the LASP may be a risk factor for cryptogenic stroke. Further research is needed to determine the prevalence of atrial septal pouch (ASP) in the general population, its clinical significance, and guidelines for treatment implications.
ABSTRACT
BACKGROUND: We discuss an unusual association: double atrial septum, pulmonary artery aneurysm, and severe regurgitation of multiple valves. CASE SUMMARY: A 70-year-old man was admitted into the hospital because of progressive dyspnoea. Physical examination showed a blood pressure of 132/70 mmHg, a systolic murmur on the right upper sternal border, another systolic murmur at the apex, and a diastolic murmur at the lower left sternal border. Electrocardiogram revealed atrial fibrillation and complete left bundle branch block. Transthoracic echocardiography showed mitral prolapse, severe mitral, aortic, and pulmonary regurgitation, a 60 mm diameter pulmonary artery aneurysm, mild to moderate tricuspid regurgitation, and moderate pulmonary hypertension. Transoesophageal echocardiography also showed an unusual atrial communication consisting of a double atrial septum with a mid-line chamber between both atria. A cardiac magnetic resonance scan was performed and confirmed echocardiography findings and QP:QS ratio = 1.3. DISCUSSION: In our knowledge, this is the first case report with this association. We present the main clinical features of the double atrial septum with persistent interatrial space, its echocardiography anatomy, differential diagnosis, and embryology.
ABSTRACT
Chromosome 4q deletion is one of the most frequently detected genomic imbalance events in congenital heart disease (CHD) patients. However, a portion of CHD-associated 4q deletions without known CHD genes suggests unknown CHD genes within these intervals. Here, we have shown that knockdown of SORBS2, a 4q interval gene, disrupted sarcomeric integrity of cardiomyocytes and caused reduced cardiomyocyte number in human embryonic stem cell differentiation model. Molecular analyses revealed decreased expression of second heart field (SHF) marker genes and impaired NOTCH and SHH signaling in SORBS2-knockdown cells. Exogenous SHH rescued SORBS2 knockdown-induced cardiomyocyte differentiation defects. Sorbs2-/- mouse mutants had atrial septal hypoplasia/aplasia or double atrial septum (DAS) derived from impaired posterior SHF with a similar expression alteration. Rare SORBS2 variants were significantly enriched in a cohort of 300 CHD patients. Our findings indicate that SORBS2 is a regulator of SHF development and its variants contribute to CHD pathogenesis. The presence of DAS in Sorbs2-/- hearts reveals the first molecular etiology of this rare anomaly linked to paradoxical thromboembolism.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Cell Differentiation , Chromosome Disorders/genetics , Heart Defects, Congenital/genetics , Human Embryonic Stem Cells/metabolism , Myocytes, Cardiac/metabolism , RNA-Binding Proteins/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adolescent , Animals , Case-Control Studies , Child , Child, Preschool , Chromosome Deletion , Chromosome Disorders/diagnosis , Chromosomes, Human, Pair 4/genetics , Databases, Genetic , Female , Gene Expression Regulation, Developmental , Genetic Predisposition to Disease , HEK293 Cells , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/metabolism , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Human Embryonic Stem Cells/pathology , Humans , Infant , Infant, Newborn , Male , Mice, Inbred C57BL , Mice, Knockout , Mutation , Myocytes, Cardiac/pathology , Phenotype , RNA-Binding Proteins/metabolism , Receptors, Notch/genetics , Receptors, Notch/metabolism , Signal TransductionABSTRACT
Double atrial septum is very rare atrial septal malformation which has double layered atrial septum with persistent interatrial space between the two atria. Clinically, most cases of this anomaly are asymptomatic unless manifest as thromboembolic complications, such as stroke, or transient ischemic attack, that thrombus may be originated from this interatrial space. We report a case of a 69-year-old man who was diagnosed with isolated double atrial septum by transthoracic echocardiography.
ABSTRACT
Double atrial septum is very rare atrial septal malformation which has double layered atrial septum with persistent interatrial space between the two atria. Clinically, most cases of this anomaly are asymptomatic unless manifest as thromboembolic complications, such as stroke, or transient ischemic attack, that thrombus may be originated from this interatrial space. We report a case of a 69-year-old man who was diagnosed with isolated double atrial septum by transthoracic echocardiography.
