Chest pain and Bradycardia

An elderly male complained of chest pain.  He had no previous cardiac history and was only on aspirin, a statin, and a proton pump inhibitor. He was hypotensive but in no distress and well perfused.  Here is the prehospital ECG:The heart rate is 38.  There are no p-waves and the baseline appears to fibrillate.  Thus, there is new atrial fibrillation with a slow response.  The ventricular rate is regular.  The QRS is narrow.  There is inferior ST elevation and ST depression in V1-V4.  Diagnosis: Atrial Fibrillation with complete (3rd degree) AV block and inferoposterior STEMI.The medics activated the cath lab.In the 1980's, it was believed that the right precordial ST depression that frequently accompanies inferior STEMI was due to "anterior subendocardial ischemia."  Then numerous angiographic studies refuted this and showed that it is almost always due to posterior STEMI.   [There are exceptions to this and in most cases the patient has reason for demand ischemia - hypotension and/or tachycardia - AND the ST depression is diffuse, including the precordium].Atrial fibrillation in STEMI: Atrial fibrillation is uncommonly an acute and immediate result of STEMI, but is a common pre-existing condition in elderly patients with STEMI.  When new onset, it is usually accompanied by a rapid ventricular response because the patient is not already on AV nodal blockers.When initiated in acute STEMI, atrial fibrillation may be du...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs