ABSTRACT
Atrial fibrillation (AF) is the most prevalent arrhythmia worldwide. The presence of AF is associated with increased risk of systemic thromboembolism, but with the uptake of oral anticoagulant (OAC) and implementation of a holistic and integrated care management, this risk is substantially reduced. The diagnosis of AF requires a 30-s-long electrocardiographic (ECG) trace, irrespective of the presence of symptoms, which may represent the main indication for an ECG tracing. However, almost half patients are asymptomatic at the time of incidental AF diagnosis, with similar risk of stroke of those with clinical AF. This has led to a crucial role of screening for AF, to increase the diagnosis of population at risk of clinical events. The aim of this review is to give a comprehensive overview about the epidemiology of asymptomatic AF, the different screening technologies, the yield of diagnosis in asymptomatic population, and the benefit derived from screening in terms of reduction of clinical adverse events, such as stroke, cardiovascular, and all-cause death. We aim to underline the importance of implementing AF screening programmes and reporting about the debate between scientific societies' clinical guidelines recommendations and the concerns expressed by the regulatory authorities, which still do not recommend population-wide screening. This review summarizes data on the ongoing trials specifically designed to investigate the benefit of screening in terms of risk of adverse events which will further elucidate the importance of screening in reducing risk of outcomes and influence and inform clinical practice in the next future.
ABSTRACT
OBJECTIVE: To explore the utility of comparative genomic hybridization to BAC arrays (array CGH) for prenatal diagnosis of microphthalmia and linear skin defects syndrome. METHODS: We used karyotype analysis, FISH and array CGH to investigate an X;Y translocation. Replication studies were done on cultured amniocytes and lymphoblasts. RESULTS: We describe a severe case of MLS syndrome that presented prenatally with multiple anomalies including cystic hygroma, microphthalmia, intrauterine growth restriction and a complex congenital heart defect. Cytogenetic analysis of amniocytes revealed an unbalanced de novo translocation between chromosomes X and Y [karyotype 46,X,der(X)t(X;Y)(p22.3;q11.2).ish der(X)(DXZ1+,DMD+,KAL-,STS-,SRY-),22q11.2 (Tuple1 x 2)]. MLS diagnosis was made at birth and the prenatal karyotype was confirmed. Replication studies showed the derivative X chromosome was the inactive X. Array CGH confirmed the X and Y imbalances seen in the karyotype and also showed twelve BACs in the MLS region were deleted as a result of the translocation. FISH with BAC clones verified the array findings and placed the X breakpoint in Xp22.2, resulting in the amended karyotype, 46,X,der(X)t(X;Y)(p22.2;q11.2).ish der(X)(DXZ1+,DMD+,KAL-,STS-,SRY-),22q11.2(Tuple1 x 2) arr cgh Xp22.33p22.2(LLNOYCO3M15D10 -->GS1-590J6)x 1,Yq11.222q23(RP11-20H21-->RP11-79J10)x 1. CONCLUSION: The sensitivity of array CGH was valuable in detecting monosomy of the MLS critical region. Array CGH should be considered for the prenatal diagnosis of this syndrome.
