12. Percutaneous balloon angioplasty for critical aortic coarctation in newborns and infants: Is it still a valid option?

Coarctation of aorta may present as severe heart failure in infants and may lead to myocardial dysfunction. Current evidence supports surgical management of neonatal coarctation. However, it can be precarious in critically sick infants. Aim and objective: To investigate the safety, efficacy, immediate and mid-term outcome of percutaneous balloon angioplasty (BAP) for infantile aortic coarctation in critically sick patients. Methods and patients: Data of all patients under age of 6 months who underwent balloon angioplasty for coarctation were reviewed. Results: Between January 2008 and April 2014, 15 infants were identified with coarctation with a mean weight of 3.4 kg (1.4–5 kg) and median age of 54 days (4–142 days). All patients were critically sick, needed admission in intensive care unit for inotropic or ventilatory support. All underwent successful percutaneous balloon angioplasty with no major complications. The clinical condition and left ventricular function improved leading to discontinuation of prostaglandin and weaning from inotrope and ventilator support. Seven patients underwent elective surgical repair after a mean time of one month, three needed re-dilation and five continued without any further intervention. Conclusions: Surgical repair for native neonatal and infantile coarctation is a preferred choice of treatment but it can be challenging in critically sick patients. However, balloon dilation remains a safe and effective temporary palliation for the critically sick patients. Despite of high incidence of restenosis, some patients do not need for mid-term further intervention

Congenital Long QT Syndrome: An Update and Present Perspective in Saudi Arabia

Primary cardiac arrhythmias are often caused by defects, predominantly in the genes responsible for generation of cardiac electrical potential i.e. cardiac rhythm generation. Due to the variability in underlying genetic defects, type and location of the mutations and putative modifiers, clinical phenotypes could be moderate to severe, even absent in many individuals. Clinical presentation and severity could be quite variable, syncope or sudden cardiac death (SCD) could also be the first and the only manifestation in a patient who had previously no symptoms at all. Despite usual familial occurrence of such cardiac arrhythmias, disease causal genetic defects could also be de novo in significant number of patients. Long QT syndrome (LQTS) is the most eloquently investigated primary cardiac rhythm disorder. A genetic defect can be identified in ~70% of definitive LQTS patients, followed by Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) and Brugada syndrome (BrS), where a genetic defect is found i

An intronic mutation leading to incomplete skipping of exon-2 in KCNQ1 rescues hearing in Jervell and Lange-Nielsen syndrome

Romano-Ward syndrome (RWs) and Jervell and Lange-Nielsen Syndrome (JLNs) are two inherited arrhythmia disorders caused by monoallelic or bi-allelic mutations, respectively, in the KCNQ1 or KCNE1 genes. Both disorders could cause Long QT syndrome either without deafness (RWs), or with deafness (JLNs). We have performed clinical, molecular and functional investigation in two consanguineous Arabian families with history of sudden death of several children. Importantly, none of the affected individuals had (or have) any hearing impairment. Homozygosity mapping followed by molecular analysis identified a novel splice acceptor site mutation (homozygously) in intron-1 of the KCNQ1 gene (c.387 -5T>A), in these two apparently unlinked families. RNA analysis revealed that this splice site mutation causes incomplete transcriptional aberration of the KCNQ1 gene, leaving 10% of the normal allele transcript intact, which restores the hearing function. Our molecular and functional data provide the first evidence that small amount (as low as 10%) of normal KCNQ1 current can effectively maintain the hearing function but fails to maintain cardiac repolarization characteristics within normal limits. Additionally, we have revealed four extra low frequency aberrant isoforms emphasizing the importance of intronic and other non-coding sequences in maintaining cellular homeostasis as pathologic changes in a single nucleotide can affect splicing events at distant sites. The novel KCNQ1 mutation found in this study is very likely a founder mutation in the southern province of Saudi Arabia emphasizing its screening in the LQT population in this regio