This is the case of a 56 year old male admitted 2 days prior for headache which turned out to be ICH patient was treated on a medical ward for this. His vital signs were stable and sustained no neurological deficits. The next evening, the medical on call was contacted for this patient for unilateral leg pain and swelling, which was appropriately investigated with doppler ultrasound. Results showed a DVT. The decision was made NOT to heparinize the patient due to his ICH. This decision was multidisciplinary involving the patient and family (including his son who is a HCP) with neurology and internal medicine. Next morning, the patient developed chest pain and the above EKG was taken see fig. 1.
A few minutes later the patient arrested and CPR was done as per ACLS protocol. This EKG was compared to the EKG done on admission, two days prior, see fig 2. So what was the reason for the arrest? The only investigation done prior to the arrest and subsequent death was the EKG in Fig. 1 This EKG has many telltale findings that could explain what made this patient arrest. There are ST-segment elevations in both the inferior leads and anterior leads. There is also ST-segment elevation in aVR of greater that 0.5 mV. There is pooled data demonstrating that this finding has approximately 78% sensitivity and 83% specificity for left main coronary artery disease.
Alternatively, this finding can also be the result of multi-vessel disease of acute proximal LAD or less commonly left circumflex or RCA.(1) To favor left main coronary artery occlusion ST-Elevation of AvR would be greater than that of V1, which is not the case in the above fig 1 EKG (2) In keeping with which territory the occlusion has occurred or what has caused the arrest, an ST-segment elevation inferiorly that is greater in lead III than in lead II, accompanied by ST-segment depression in lead aVL, I, or both, is 90% sensitive and 71% specific for right coronary artery occlusion. (3) With this evidence at hand, I believe this is more likely to be a very unlikely EKG presentation of RCA occlusion rather than a left main coronary occlusion. Furthermore, this extensive RCA occlusion was likely to be accompanied by RV infarction.
ST segment elevation is usually greater in lead III than in lead II when right ventricular infarction coexists with inferior AMI.(4) A coexistent reciprocal change with inferior STEMI is associated with larger infarct size and increased mortality.(5) A completely different theory was challenged. The patient had a DVT diagnosed and was not treated for it, then developed chest pain. Could the arrest and EKG finding be due to a PE? We know that PE can well cause ST-elevation in aVR. The fact that there is ST-depressions in lead I and aVL increases the sensitivity that this is AMI up to 84%.(6) Reciprocal findings are not present in PE. Also, PE does not cause ST-elevation in the inferior leads. And in keeping with AMI, the inferior leads have pathological Q waves. With all that said, my opinion is that this is a case of RCA occlusion with RV infarct, that caused the arrest of this patient.
Note! Consent has been taken from the patient’s son to publish the EKG.
1. Rostoff P, et al: Electrocardiographic prediction of acute left main coronary artery occlusion. Am J Emerg Med 2007 Sep;25(7):852-5.
2. Yamaji H, et al: Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V1. J Am Coll Cardiol. 2001 Nov 1;38(5):1348-54.
3. Zimetbaum PJ, Josephson ME: Use of the electrocardiogram in acute myocardial infarction. N Engl J Med 2003 Mar 6;348(10):933-40.
4. Zehmer U, et al: Effects of fibrinolytic therapy in acute myocardial infarction with or without right ventricular involvement. J Am Coll Cardiol 1998; 2:876
5. Martin TN, Groenning BA, Murray HM et al. ST segment deviation analysis of the admission of 12 lead ECG as an early diagnosis of AMI with cardiac Magnetic Resonance Imaging as gold standard. J Am coll cardiol. 2007;50(11):1021-1028. doi:10.1016/j.jacc.2007.04.090
6. Saw J, Davies C, Fung A, Spinelli JJ, Jue J: Value of ST elevation in lead III greater than lead II in inferior wall acute myocardial infarction for predicting in-hospital mortality and diagnosing right ventricular infarction. Am J Cardiol Feb 15;87(4):448-50, A6.