Ray Fowler, MD is Professor of EM / EMS at UTSW / Parkland. Edited by Alex Koyfman, MD.
45 male with intense epigastric pain radiating to his left arm with associated NV and diaphoresis.
Note the pulse rate of about 50 with ST elevation in the inferior leads, reciprocal depression in I and L. Note the ST depression in V2. This is an acute infero-posterior myocardial infarction. Bradycardia is common with an AIMI, as is nausea, due to pronounced vagal effect of this MI. Be cautious with the use of nitrates in this patient!
55 female with crushing anterior chest pain and diaphoresis.
Note the “Up in 1, down in III and aVF” with an axis of -53 degrees. This is left anterior fasicular block.
There is also a right bundle branch block present.
There is ALSO an acute, anteroseptal MI present with reciprocal depression in the inferior leads.
This patient is likely infarcting her septum, as two of the three bundles are blocked. Activate the cath lab, and put pacing pads on the patient!!!
Notice the bradycardia! The first thing to do is check vital signs. Evidence of shock would be strong indication to consider pacing this patient.
You have a slow rate with a wide QRS complex that is perfectly regular. P waves are absent. This is likely “sinus arrest” with a ventricular escape rhythm.
Notice also the odd, almost Brugada look to V1! Remember that Brugada is thought to be responsible for as many as 1 in 20 cardiac arrests in the United States!
A sinus tachycardia is present in this 54 year old man with severe chest pain radiating to the left arm.
Note the ST depressions fairly diffusely BUT there is ST elevation in aVR and V1. Remember that aVR and V1 are looking right at the left coronary artery.
This sort of tracing can be indicative of a left main coronary artery lesion, which may need to go to the OR. It also may be indicative of diffuse coronary artery disease.
This is a narrow complex tachycardia in a 31 year-old female that is perfectly clock regular. There is no obvious atrial activity seen. The QRS is narrow.
This is “supraventricular tachycardia”. Remember, though: 220 - age is the maximum sinus tachycardia for a patient. 220 - 31 = 189 that is the maximum sinus tachycardia that this patient could muster. So, BE SURE that this patient does NOT have evidence of some condition such as sepsis, hemorrhagic shock, thyrotoxicosis, or drug ingestion!
This 65 year-old woman presents with lightheadedness and worsening dyspnea on exertion.
The QRS rate is 99, the rhythm is regular, and there is a P wave for every QRS. The QRS complex is wide.
Look at the “right side of the heart”, which is V1. There is no “RSR” pattern there, just deep S waves in V1-3. Look at the “left side of the heart”, which is V6. There is a big, upright fat R wave with some modest ST depression.
This is “left bundle branch block”. Note that about half of LBBB’s have left axis deviation, and about half have normal axis. Do you remember the Sgarbossa Criteria???
This 81 year old man had a syncopal episode. He presents a little confused, GCS 14 (lies with his eyes closed), and is “not right” per his wife. His BP is 110/76, and he has the cardiogram below.
The rate is normal, the rhythm is regular, there is a P wave for every QRS, and the QRS is narrow. There is ST elevation in 1, L, and V2, with reciprocal depression in the inferior leads. This is an acute anterolateral myocardial infarction.
The PR interval is slightly prolonged, which is a “first degree AV block”.
Notice how leads V5 and V6 show ST depression. Sometimes all of the leads in the “group” don’t show ST elevation.
Remember that the “group” of leads (anterior, inferior, and lateral) are given that distinction because it is where the leads are “positive”. Leads 1, aVL, and V6 are all positive in about the same location. Likewise for II, III, and aVF as “inferior leads” and V1 - V4 as “anterior leads”.
This is a very difficult strip. The rate is slow and irregular, with a suggestion of “regular irregularity”. There is an underlying atrial rhythm (P waves) at a rate of about 80 (look at lead III). However, these P waves probably are not conducted to the ventricles. Look at the two P waves seen in V2. The first one is not conducted, and the second one, which is right in front of the QRS, has too short of a PR interval to be conducted.
Thus, this is PROBABLY a complete heart block (3rd degree block) with a ventricular bigeminal rhythm.
CHECK A BLOOD PRESSURE!!! Get the patient onto pacing pads quickly….and CALL THE CARDIOLOGIST RIGHT AWAY, while getting a line, drawing labs, getting some oxygen, and keeping a close eye on this patient. Next stop could be asystole!
This is an odd 12 lead ECG to have done in this 54 year old man. The rate is profoundly slow, in the 20’s or so. The rhythm is regular. There is no evident atrial activity. The QRS is very widened.
A rhythm like this is usually the “agonal rhythm” seen in a very slow pulseless electrical activity. That patient would be apneic and pulseless, which is why it is strange to have a tracing like this at all. You wouldn’t stop to do a 12 lead while working a cardiac arrest!!
On the other hand, perhaps this was a hemodialysis patient who actually had a reasonable blood pressure and was awake, so the medics saw the bradycardia on the monitor and did a 12 lead to look further. What could be the cause of this absence of atrial activity and very wide and slow QRS rate? Could this patient use a little calcium, albuterol, bicarb, and glucose/insulin? Thoughts?
