Heart Failure -> Cardiac Resynchronization Therapy: -> Indications D-PO03 - Poster Session III (ID 48) Poster

D-PO03-070 - Change In QRS Area After Cardiac Resynchronization Therapy Is Associated With Clinical Response (ID 305)


Background: Cardiac Resynchronization Therapy (CRT) is the cornerstone of treatment in patients with dyssynchronous heart failure. Recently, baseline QRS area derived from vectorcardiography, proved to predict outcome in CRT better than QRS duration and morphology.
Objective: To investigate whether the change in QRS area (∆QRS area) with CRT-pacing further improves the prediction of CRT outcome.
Methods: We conducted a retrospective analysis on 1,299 patients, included in a CRT-registry from three University hospitals. Optimal cut-offs for ∆QRS area and -duration were found at 62µVs and -11ms, respectively. Primary endpoint was a combination of all-cause mortality, heart transplantation, and left ventricular assist device implantation. Secondary echocardiographic end point was defined as ≥15% reduction in left-ventricular end-systolic volume.
Results: Survival analyses showed a relative risk reduction of 57% in the ∆QRS area ≥ 62 µVs group. Dividing the cohort into four groups with baseline- ≥ and < 109 µVs and ∆QRS area ≥ and < 62 µVs showed a significantly better outcome in patients with both high baseline- and high ∆QRS area. (figure). Additionally, patients with the combination of high baseline- and high ∆QRS area had the best echocardiographic outcome (figure).
Conclusion: In patients with high baseline QRS area, there is a clear distinction between high and low ∆QRS area, and this may indicate a role in identifying patients with amenable substrate that may profit from optimization of device or heart failure treatment.