The clinical presentation of posterior myocardial infarction (PMI) is not always easy, not even for the cardiologist. True posterior myocardial infarction is difficult to recognise because the leads of the standard 12-lead electrocardiogram are not a direct representation of the area involved. Only with indirect changes in the precordial leads as such the diagnosis can be suspected. It is suggested to be one of the most commonly missed types of acute myocardial infarction (MI) electrocardiographic patterns.
A 47-years-old caucasian former 22 pack per year smoker with no significant PMHx presented with complaint of upper back pain radiating to both shoulders that started during a business meeting. He went home had some beers and rested. He slept and woke up at 11:30PM with severe pain in b/w shoulders: sharp, 10/10, constant with no aggravating or alleviating factors. The pain progressed to involve his both arms and chest and he got worried, therefore, decided to go to the ED where EKG changes and troponin elevation were noted. He reported nausea, palpitations. Denied SOB, diaphoresis, fever, cough, chills, physical exertion, trauma. His father had an MI at 53 yo. EKG was noted with: ST/T depression in inferolateral leads with loss of T wave balance in V1 and R wave in V2 taller than V3. Troponin elevation to 2.25 . The patient was taken emergently to cardiac cath and he was noted to have: patent Left main artery, patent left anterior descending artery, mild disease in the mid right coronary artery, and 100% occlusion of the Left Circumflex coronary artery. A drug eluting stent was placed.
True isolated posterior STEMI is rare and comprises of 3% of total STEMI and missed frequently in ER as well as in patient setting. Posterior STEMI associated with inferior or lateral MI is very common and comprises of 20% of the STEMI cases and usually not missed due to STEMI changes in inferior or lateral leads. Missed STEMI leads to increased cardiac morbidity and mortality and thus for clinicians it is very important to read each and every EKG for the patients presenting with suspected coronary disease. Our patient had back pain and first clinical impression was aortic dissection that was ruled out with CXR and urgent TTE. With back pain, elevated troponins and Tall R wave in lead V2 in the absence of any other causes of elevated troponin, posterior STEMI was suspected leading to emergent LHC that was suggestive of total occlusion of circumflex artery that was stented with a drug eluting stent with good flow was noted after that (TIMI 3 flow). Patient did well and was discharged home on same day with maximal medical therapy.||