QT interval estimation in patients with right bundle branch block using validated formulas for left bundle branch block

CONCLUSIONSPreviously described formulas for LBBB exhibit marked differences regarding reliability in the estimation of QTc interval in the setting of RBBB. According to our results, Yankelson ’s method shows the most consistent agreement when estimating baseline QTc interval in patients with RBBB. Table 1.LBBB METHODFormula to estimate baseline QTcPearson’s R correlation coefficientCI (95%)Intraclass correlation coefficientCI (95%)YankelsonQTc - QRS + 95 (m) or 88 (f)0.805(0.632-0.97 7)0.882(0.788-0.934)Bogossian**QT - (QRS/2)0.813(0.644-0.982)0.756(-0.127-0.919)Wang**QT - (0.86*QRS - 71)0.801(0.627-0.974)0.834(0.465-0.930)Tang-Rabkin0.945*QTcRabkin - 260.722(0.521-0.923)0.711(0.019-0.885)RautaharjuQT - 155*(60/heart rate - 1) - 0.93*(QRS - 139) - 22 (m) or - 34 (f)0.780(0.599-0 .961)0.105(-0.017-0.381)**Bogossian and Wang required additional HR correction (Bazett).  Abstract Figure 1. Bland-Altman
Source: Europace - Category: Cardiology Source Type: research