Specificity of the wide QRS complex tachycardia algorithms in recipients of cardiac resynchronization therapy.

BACKGROUND

We assessed the specificity of wide QRS complex tachycardia (WCT) differentiating algorithms in patients with preexistent left bundle branch block (LBBB) and heart failure.

METHODS

Three hundred fourteen patients with resynchronization devices were retrospectively screened. electrocardiograms with supraventricular LBBB rhythm were used as a surrogate for supraventricular tachycardia QRS morphology. The Pava lead II criterion, ventricular activation velocity ratio (Vi/Vt) ratio in V(2), Vereckei aVR, Brugada, Griffith, and Bayesian algorithms were investigated.

RESULTS

The WCT algorithms had a lower specificity (33%-69%) in patients with LBBB than in general WCT populations. The Pava lead II criterion and Brugada algorithm had higher specificity than other algorithms (P < .05). Several of the single criteria (absence of an RS complex in V(1) through V(6), initial R wave in aVR, Vi/Vt < 1 in V(2)) had specificities of 92% to 99%.

CONCLUSIONS

In patients with heart failure and LBBB, an electrocardiographic diagnosis of ventricular tachycardia should be based on selected, specific criteria rather than on WCT algorithms.