2024年10月8日 · Electrocardiographic features that increase the likelihood of VT include: Absence of typical RBBB or LBBB morphology. Extreme axis deviation (“northwest axis”): QRS positive in aVR and negative in I and aVF. Fusion beats: Occur when a sinus and ventricular beat coincide to produce a hybrid complex (see Dressler beat)

Kindwall and colleagues used the following criteria to distinguish ventricular tachycardia (VT) from supraventricular tachycardia (SVT) with aberrant conduction in patients with LBBB-like morphology: (1) R wave in lead V1 or V2 > 30 ms; (2) any Q wave in V6; (3) a duration of ≥ 60 ms from the onset of the QRS to the nadir of the S wave in V1 ...

2024年8月27日 · Differentiating between SVT with aberrancy and ventricular tachycardia (VT) can be a challenging task, even for experienced healthcare providers. This blog aims to clarify the distinction between these two cardiac arrhythmias, emphasizing the potential dangers of misdiagnosis and the importance of accurate identification.

2013年11月22日 · Determine if you have a LBBB morphology (dominant S wave in V1) or a RBBB morphology (dominant R wave in V1) then use the appropriate section below to help differentiate.

SVT with LBBB. In panel A LBBB changes during tachycardia into a narrow QRS following a ventricular premature beat. As described in the text, lead V1 during LBBB clearly shows signs pointing to a supraventricular origin of the tachycardia. Figure 10: Concordant pattern.

2024年10月8日 · Left bundle branch block (LBBB): 1) rS complex in V1 (tiny R wave, deep S wave) 2) Characteristic lateral lead morphology in V5-6 3) Note appropriate discordance in V1 …

2003年10月14日 · A QRS width of more than 0.14 seconds with right bundle-branch block (RBBB) or 0.16 seconds during LBBB pattern favors VT. The QRS width criteria are not helpful for differentiating VT from SVT with AV conduction over an accessory pathway.

LVOT VT is suggested by LBBB morphology with inferior axis with small R-waves in V1 and early precordial transition (R/S = 1 by V2 or V3) or RBBB morphology with inferior axis (2-3) and presence of S-wave in V64 (Figure 1b). Aortic sinus cusp origin is sometimes difficult to differentiate from RVOT VT because both are so close to each other.

EPS revealed orthodromic atrioventricular reciprocating tachycardia (AVRT) involving a left sided concealed pathway. This report demonstrates the clues provided by spontaneous bundle branch aberrancy during SVT in predicting the mechanism of tachycardia.

2025年3月17日 · SVTのほとんどの症例において、QRS幅はRBBBパターンでは140ms、LBBBパターンでは160msであることが指摘されています 2)。 したがって、これより広いQRS幅は変行伝導である可能性が低く、VTがより可能性の高い診断となります。