Cardiometrix

Wide QRS complex tachycardias are a diagnostic challenge, often requiring careful assessment to differentiate between ventricular and supraventricular origins. Accurate diagnosis is crucial due to implications for treatment and prognosis. Widened QRS on ECG may indicate a delay in electrical conduction due to a BBB (Bundle Branch Block). Pathophysiology of Wide QRS Complexes A wide QRS complex (>0.10–0.12 seconds) arises from delayed ventricular depolarization. Differential diagnoses include: Aberrant Conduction: Often observed in tachycardias or bradycardias with phase 4 block. Electrolyte Disturbances: Hyperkalemia can exacerbate QRS widening. Drug Effects: Class IC antiarrhythmics, such as flecainide, prolong ventricular conduction times. Structural Pathology: Underlying ARVC can contribute to intraventricular conduction delay. As highlighted by Bala (2024), accurately identifying right and left bundle branch blocks (RBBB and LBBB), paced rhythms, or accessory pathways is cru...

P otentially lethal inherited arrhythmia syndromes could be inherited. The list of potentially associated genes is growing.  Long QT syndrome has been linked with LQTS;  KCNH2 ,  KCNQ1 ,  SCN5A;  Brugada syndrome to  SCN5A , arrhythmogenic cardiomyopathy to  LMNA , and catecholamine-induced polymorphic ventricular tachycardia to RYR2 .  Characteristic TU–Wave Patterns Predict the KCNJ2 Genotype eMERGE-III  study analyzes phenotype and genotype data for individuals with health problems as well as healthy volunteers.  Through  this study,  109 Mendelian disease genes, including 10 associated with arrhythmias, were sequenced in 21,846 individuals who had no indication for arrythmia-related genetic testing. In 1,838 patients, researchers found never-before-seen variations in the 10 genes associated with genetic arrhythmia, highlighting the problem of variants of unknown significance in the  new era of genomic medicine for card...