Unicuspid aortic valve, hand anomalies: a heart-hand syndrome

Unicuspid aortic valve: a rare congenital anomaly

Unicuspid aortic valve (UAV) is a rare congenital aortic valve anomaly. It has two subtypes and often is associated with aortic valve dysfunction and corresponding clinical presentations. Echocardiography is the first choice of diagnostic method for UAV. Three-dimensional echocardiography has played an increasingly important role in diagnosis, intraprocedural guidance, and post-procedural assessment in recent years. There remain challenges in distinguishing UAV from bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV). Misdiagnosis is most resulted from raphes or leaflet calcifications. Multi-modality imaging has obvious advantages over single-modality imaging and is crucial for UAV diagnosis. Accurate identification of aortic valve morphology is important to choose the best treatment. Aortic balloon valvoplasty, surgical valvotomy, commissurotomy, Ross procedure, surgical valve repair and surgical replacement are most common treatment modalities of UAV. In this review, we aim to discuss UAV including epidemiology, definition, classification, diagnostic importance and necessity, valvular function, clinical presentation, associated disorders, non-invasive diagnostic modalities and therapeutic approaches.

Rare Case of Ulnar-Mammary-Like Syndrome With Left Ventricular Tachycardia and Lack of TBX3 Mutation

"Heart-hand" type syndromes represent a group of rare congenital conditions that combine cardiac pathology (structural defect or arrhythmic disorder) and limb abnormality. Significant clinical variability and genetic heterogeneity typical for such syndromes complicate correct diagnosis, prognosis, and appropriate genetic counseling of the affected families. By now, only single genes have been unambiguously determined as a genetic cause of heart-hand syndromes and phenotypically similar conditions. In the present study, we report on a 25-year-old Russian female patient with a clinical picture resembling ulnar-mammary syndrome (UMS). Principal clinical manifestations included heart septal fibrosis and non-sustained left ventricular tachycardia combined with fifth finger camptodactyly, hypoplastic breast, abnormal teeth, and mental retardation. Target Sanger sequencing and array-based comparative genome hybridization confirmed the lack of pathogenic mutations and large-scale deletions in TBX3 (12q24.21), the only gene known to be associated with UMS cases to date. Based on the results of whole-exome sequencing, 14 potential candidate variants were identified. Among them, a novel missense variant in SYNM gene (exon 1, c.173C > T, p.A58V), encoding intermediate filament protein synemin was characterized. Until the present, no association between SYNM mutations and congenital clinical syndromes has been reported. At the same time, taking into account synemin tissue-specific expression profiles and available data on abnormal knock-out mice phenotypes, we propose SYNM as a candidate gene contributing to the UMS-like phenotype. Further comprehensive functional studies are required to evaluate possible involvement of SYNM in genesis of complex heart-limb pathology.

Unicuspid aortic valve presenting with cardiac arrest in an adolescent

Unicuspid aortic valve (UAV) is a rare congenital anomaly typically affecting patients in their fourth and fifth decades and presenting with signs of heart failure. Our case is one of a previously asymptomatic teenage girl with a UAV, who presented with cardiac arrest and was successfully treated. Only two other similar cases have been reported in the literature, both were of slightly older male patients. Our case highlights the morbidity associated with the anomaly supporting the need for careful assessment of the valve in cases where UAV is suspected.