A 67 y.o. male arrests in front of EMS and his EKG is shown below

Would you call the cath lab?

Our patient had hyperkalemia.  His second EKG is shown below. 

The pt had a hx of seizures and was found in an empty bath tub.  He initially had agonal respirations and a weak pulse but arrested in front of EMS.   K was 7.9 and lactate was 9.7  He was found to have a SDH on CT. The cath lab was called but felt the changes were due to electrolyte abnormalities and did not cath the pt.

Although this case was hyperkalemia AV blocks do exist with MIs.

High degree AV block occurs in 9.8% with inferior MI and 3.2% with anterior MI in large studies.  High degree AV block associated with inferior MIs is located proximal to the bundle of His and the QRS is usually narrow.  High degree AV associated with anterior MI is usually distal to the AV node and is associated with high mortality and a widened QRS.

Inferior MI  can be associated with sinus brady, Mobitz I, and complete heart block since the SA node, AV node and his bundle are most often supplied by the RCA. Anterior MI is associated most often with a Mobitz II block and can cause complete heart block.

Pacing is recommended for symptomatic complete heart block, alternating right and left bundle branch block, symptomatic bradycardia and Mobitz I second-degree AV block.

Meine TJ, Al-Khatib SM, Alexander JH, et al. Incidence, predictors and outcomes of high-degree atrioventricular block complicating acute myocardial infarction treated with thrombolytic therapy. Am Heart J 2005;149;670.

Hunt D, Sloman G, Bundle-branch block in acute myocardial infarction. 1969. Brit. Med J. 1(5636):85-8.

Sgarbossa EB, Pinski SL, Barbageleta A, et al. Electrocardiographic diagnosis of evolving acute myocardial infarction in the presence of left bundle branch block. GUSTO-1

N Engl J Med 1996;334:481-7.

Wilner B, deLemos, J, Neeland I. LBBB in patients with suspected MI: an evolving paradigm. 2017. American College of Cardiology.