Abstract Background Inherited arrhythmia syndromes (IAS) are a group of rare disorders that result from genetic mutations in several genes encoding ion channels causing disruption in its structure and function and predispose affected individuals to various symptoms including sudden cardiac death (SCD). They include congenital long QT syndrome, Brugada syndrome (BrS), progressive cardiac conduction disease, short QT syndrome and Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT). There have been few reports of long QT syndrome from the Arabian Gulf region but this is the first comprehensive review of multiple inherited arrhythmia syndromes in the region. Objectives Our objective are to describe the demographics of children and adults with inherited arrhythmia syndromes, report the presenting clinical features, genetic mutations and management strategies. Also, to report some unique and rare genetic findings in our population. Methods This is a descriptive retrospective study that included children and adults with inherited arrhythmia syndromes diagnosed and treated at a national heart center over 16 years, between 2006 to 2022. Data collected included patient demographics, geographical distribution, clinical features, genetic reports and management strategies. Result One hundred and six patients were included in the analysis. Sixty-six (62.3%) were males, and 68 (64.2%) were adults and 38 (35.8%) were children. Three inherited arrhythmia syndromes were found in our population that included Long QT, Brugada and catecholaminergic polymorphic ventricular tachycardia (CPVT), which accounted for 58 (54.7%), 39 (36.8%) and 9 (8.5%), respectively. Seventy-six (71.7%) of the patients were reported to be from consanguineous families. Most children, 31 (91.4%) had long QT, whereas most adults, 39(54.9%) had Brugada. The clinical features varied based on the type of arrhythmia. There were 28(26.4%) asymptomatic individuals who were diagnosed incidentally. Syncope was the most common presenting symptom in patients with Long QT, 24(41.4%) and Brugada syndrome, 20(51.3%). Palpitations, 4(44.4%) and bradycardia, 4(44.4%) were the predominant presenting features in patients with CPVT. The treatment modalities included beta blockers and antiarrhythmics, implantable cardioversion defibrillators(ICDs), pacemakers, and left sympathetic ganglionectomy(LSGs). We identified 36 individuals with pathogenic or likely pathogenic variants and 12 VOUS(variants of uncertain significance) in different genes of IAS. Conclusion This is the first comprehensive study on the inherited arrhythmia syndromes in Oman and the Arabian Peninsula. We provided insights about demographics, clinical, genetic profile and the treatment strategies of the most common IAS in the region. Tis study hat will help in early detection of the different types of arrhythmias and early intervention to prevent sudden cardiac death in patients and their relatives.
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