Can you see through this paced rhythm?

Written by Pendell MeyersAn elderly female with known CAD and multiple stents, pacemaker, stroke, and COPD presented with 2 hours of midsternal, nonradiating chest pain at rest. Apparently on arrival to the ED the patient described her pain more as " crampy " abdominal pain, but also chest discomfort.Here is her initial ECG during active symptoms:What do you think?There is dual chamber paced rhythm (atrial and ventricular pacer spikes) with resulting LBBB-like morphology. There is massive excessively discordant STE in II, III, aVF, as well as V4-V6. There is reciprocal excessively discordant STD in I and aVL. Additionally, if you use your eyes to correct for the upsloping baseline in V2, there is clearly concordant STD. Thus, this is an obvious OMI of the inferior, posterior, and lateral walls until proven otherwise.The ratios are:II: 5.5 / 7 = 0.79III: 8.5 / 11 = 0.77aVF: 5 / 9.5 = 0.53V4: 3.5 / 9 = 0.39V5: 3.5 / 6 = 0.58V6: 3.5 / 3 = 1.17Of course, the modified Sgarbossa criteria only require 1 lead with at least 25% (0.25).Looking back at prior records, there were both paced and non-paced prior ECGs to compare with:The EM and cardiology teams recognized this as a paced rhythm, and commented that there was " no clear STEMI in the setting of paced rhythm, " which is true and appropriate in the setting of the current STEMI vs. NSTEMI paradigm.They started medical management and consulted cardiology.Approximately 45 minutes later, there was a spontaneous change in the rhythm o...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs