Predictors of Cardiac Resynchronization Therapy Response: The Pivotal Role of Electrocardiogram

Figure 1

Baseline Tc-99m SPECT myocardial perfusions scan from CRT candidate demonstrating a fixed perfusion defect involving anterior and anterolateral wall consistent with transmural scar. Intraoperative testing demonstrated a high pacing threshold at anterolateral LV lead position; excellent pacing threshold was obtained from a posterolateral coronary sinus branch.