Endocardial R wave electrical alternans can cause ICD sensing failure during ventricular tachycardia, which can be resolved by inserting a separate sensing/pacing lead.
May warrant vigilance for R-wave alternans in ICD patients with VT; single case leaves open need for additional sensing leads.
A 71-year-old patient underwent routine single-chamber implantable cardioverter defibrillator (ICD) generator replacement. During defibrillation threshold testing, ventricular tachycardia was induced but the ICD failed twice to properly detect the tachycardia due to endocardial R wave alternans and sensing of every other beat. The problem was resolved by inserting a separate sensing/pacing lead positioned further away from the existing ICD lead.
No takes yet. Share an insight, caveat, or question.
Jongnarangsin et al. (2002) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: