We originally published this ECG in 2012.  It was generously donated to the ECG Guru website by our friend and ECG Guru Extraordinaire, Jason Roediger.  We are re-publishing it today, as it is a great ECG for illustrating how helpful laddergrams can be for showing conduction in dysrhythmias.

This ECG has something for everyone:  The rhythm is sinus, and there is a non-conducted PAC (beat number 3) after the second beat.  Just after the next P wave, there is a ventricular escape beat which prevents that P wave from making a QRS.  The eighth beat is a PVC.  The eleventh is a conducted PAC.  You can use this ECG to illustrate for your students the concepts of "escape" beats, refractory periods, and premature beats.

There are ST changes that suggest coronary artery disease: the ST segments are flat in shape with a tiny amount of elevation in V1 through V4.  The axis is normal, at the border of normal and left axis. It is difficult to see, but there appears to be a tiny r wave in Lead III, so we cannot say for sure if there is or was a pathological Q wave in that lead.

The P waves are wide and "double" in Lead II and biphasic in V1, suggesting LV failure or mitral valve disease.  However, the criteria for LV hypertrophy are not met.

Unbelievably, this inferolateral ST elevation M.I. was missed by the treating paramedics in the field.  An elderly woman stepped off a curb and was hit by a very slow-moving car.  She fell and sustained a Colle's fracture of the right wrist. While the paramedics assessed her, she complained of chest pain, prompting them to perform a 12-Lead ECG.  The machine's interpretation called attention to the inferior and lateral walls' injury pattern, but the paramedics did not believe it, because "she was a trauma patient". They ran three ECGs, and still did not agree with the machine.

The patient was transported to a hospital without an interventional cath lab, and she was forced to endure a one-hour wait to be transferred to an appropriate hospital.

This is a great ECG for a discussion with your students about "distractors".  The call came in as a trauma, so that, in itself, was a distractor.  The rescuers saw what they expected to see. The angulated fracture distracted them - putting them into full trauma assessment mode.  Then, the frequent and coupled PVCs also distracted them, possibly making it more difficult for them to evaluate the ST segments in the normal beats.  Interestingly, the second and third ECGs did not have PVCs, and the ST elevation was even more clear.

PVCs which are repeating themselves in groups of two, three, or more are sinister in a chest pain patient, and may indicate LV dysfunction. They could possibly result in ventricular tachycardia, which would be disasterous for this patient.