exudates and Long-QT-Syndrome

Hydroxychloroquine and protease inhibitors were widely used as off-label treatment options for COVID-19 but the safety data of these drugs among the COVID-19 population are largely lacking. Drug-induced QTc prolongation is a known adverse reaction of hydroxychloroquine, especially during chronic treatment. However, when administered concurrently with potential pro-arrhythmic drugs such as protease inhibitors, the risk of QTc prolongation imposed on these patients is not known. We aim to investigate the incidence of QTc prolongation events and potential factors associated with its occurrence in COVID-19 population.. We included 446 SARS-CoV-2 RT-PCR-positive patients taking at least one treatment drug for COVID-19 within a period of one month (March-April 2020). In addition to COVID-19-related treatment (HCQ/PI), concomitant drugs with risks of QTc prolongation were considered. We defined QTc prolongation as QTc interval of ≥470 ms in postpubertal males, and ≥480 ms in postpubertal females.. QTc prolongation events occurred in 28/446 (6.3%) patients with an incidence rate of 1 case per 100 person-days. A total of 26/28 (93%) patients who had prolonged QTc intervals received at least two pro-QT drugs. Multivariate analysis showed that HCQ and PI combination therapy had five times higher odds of QTc prolongation as compared to HCQ-only therapy after controlling for age, cardiovascular disease, SIRS and the use of concurrent QTc-prolonging agents besides HCQ and/or PI (OR 5.2; 95% CI, 1.11-24.49; p = 0.036). Independent of drug therapy, presence of SIRS resulted in four times higher odds of QTc prolongation (OR 4.3; 95% CI, 1.66-11.06; p = 0.003). In HCQ-PI combination group, having concomitant pro-QT drugs led to four times higher odds of QTc prolongation (OR 3.8; 95% CI, 1.53-9.73; p = 0.004). Four patients who had prolonged QTc intervals died but none were cardiac-related deaths.. In our cohort, hydroxychloroquine monotherapy had low potential to increase QTc intervals. However, when given concurrently with protease inhibitors which have possible or conditional risk, the odds of QTc prolongation increased fivefold. Interestingly, independent of drug therapy, the presence of systemic inflammatory response syndrome (SIRS) resulted in four times higher odds of QTc prolongation, leading to the postulation that some QTc events seen in COVID-19 patients may be due to the disease itself. ECG monitoring should be continued for at least a week from the initiation of treatment.

Topics: Adult; Cohort Studies; COVID-19 Drug Treatment; Electrocardiography; Enzyme Inhibitors; Female; Humans; Hydroxychloroquine; Long QT Syndrome; Malaysia; Male; Middle Aged; Protease Inhibitors; Retrospective Studies; SARS-CoV-2

Long QT syndrome (LQTS) is predominantly a genetic cardiac arrhythmia disorder. We report here our study on long QT syndrome from two children from Kelantan, Malaysia. Clinical and genetic findings of these two unrelated Malay children with LQTS is discussed. We found a Long QT, type 1 causal mutation, p.Ile567Thr in the KCNQ1 gene in the first child. A pathogenic mutation could not be detected in the second child, explaining the heterogeneity of this disease.

Topics: Genetic Markers; Humans; Infant; Infant, Newborn; KCNQ1 Potassium Channel; Long QT Syndrome; Malaysia; Male; Mutation, Missense

To determine the genetic variability of long QT syndrome (LQTS)-associated genes (KCNQ1, HERG, KCNE1 and KCNE2) among three distinct ethnic groups in the Singapore population.. Genomic DNA samples from up to 265 normal healthy Chinese, 118 Malay and 139 Indian volunteer subjects were screened for genetic variations in the coding region of the LQTS-associated genes using denaturing high-performance liquid chromatography and sequencing analyses.. In total, 37 single nucleotide polymorphisms (SNPs) were identified in the coding exons of the LQTS-associated potassium ion channel genes, seven of which were novel nonsynonymous polymorphisms. SNPs 356G-->A (exon 1 of KCNQ1), 2624C-->T and 2893G-->A (exon 11 of HERG), 3164G-->A, 3322C-->G and 3460G-->A (exon 14 of HERG), and 79C-->T (exon 3 of KCNE2) resulted in Gly119Asp, Thr875Met, Gly965Arg, Arg1055Gln, Leu1108Val, Gly1154Ser and Arg27Cys amino acid substitutions, respectively. In addition, 16 intronic variants were detected. The functional consequence of these variants has not been studied and their association with risk of LQTS is unclear.. There exist multiple genetic polymorphisms of the LQTS-associated genes in the three distinct Asian populations. Though the functional significance of many of these SNPs is unknown, this interindividual and interethnic genetic variability may underlie the different susceptibilities of individuals to developing LQTS.

Topics: Adolescent; Adult; Amino Acid Substitution; China; ERG1 Potassium Channel; Ether-A-Go-Go Potassium Channels; Humans; India; Inteins; KCNQ1 Potassium Channel; Long QT Syndrome; Malaysia; Polymorphism, Single Nucleotide; Potassium Channels, Voltage-Gated; Singapore