Congenital Absence of the Left Circumflex Artery Presenting With Inferoposterior Wall Myocardial Infarction Due to Stenosis of the Super Dominant Right Coronary Artery: A Rare Case.

The primary coronary arteries are the right coronary artery (RCA), the left main coronary artery (LMCA), which bifurcate into the left anterior descending artery (LAD), and the left circumflex artery (LCX), arising from the right coronary sinus and left coronary sinus, respectively. The congenital agenesis of LCX is a very unusual anomaly caused by the inability of LCX to form in the atrioventricular (AV) groove. This condition is usually accompanied by the presence of a large, dominant RCA that supplies its own territory and that of LCX, i.e., the inferior, posterior, and lateral walls. This anomaly is generally detected incidentally during coronary angiography. This condition usually does not manifest as a major cardiovascular event and mildly presents as chest pain upon exertion. The chest pain is vastly attributed to ischemia in the RCA territory, as this "super dominant" vessel majorly directs its supply to the LCX territory for compensation. This is known as the steal phenomenon. In this paper, we discuss a case of a 61-year-old female who came to the ED with the chief complaint of acutely radiating chest pain for five hours and was diagnosed as a case of acute myocardial infarction of the inferior and posterior walls. Coronary angiography revealed 90% stenosis of the RCA and a congenital absence of LCX, which has a significantly low prevalence.

An Extremely Rare Case of Isolated Aortic Valve Prolapse Causing Aortic Regurgitation in the Absence of Any Other Pre-existing Cardiovascular or Non-cardiovascular Condition.

In this case report, we present an extremely rare case of isolated aortic valve prolapse causing aortic regurgitation having no association with any comorbid conditions that are commonly seen with aortic valve prolapse. A 27-year-old female patient presented with chief complaints of dyspnea on exertion (New York Heart Association grade III) for 20 days, decreased appetite for 15 days, and a history of significant weight loss for one and a half years. Transthoracic and transesophageal echocardiography revealed a trileaflet floppy aortic valve with prolapsing non-coronary and right coronary cusps, associated with moderate aortic regurgitation. The incidence of aortic valve prolapse is roughly around 1%. Exceptionally, very few cases of isolated aortic valve prolapse with moderate-to-severe aortic regurgitation without any associated pathology have been reported to date.

ST-Segment Elevation in Conditions of Non-cardiovascular Origin Mimicking an Acute Myocardial Infarction: A Narrative Review.

The most widespread presenting ailments among patients visiting the emergency department are chest pain and shortness of breath. These symptoms lead any doctor to a probable diagnosis of myocardial infarction (MI). Detailed patient history, testing of blood samples for cardiac biomarkers that are indicative of cardiovascular necrosis, ultrasound methods, electrocardiography, and coronary computed tomography (CT) could all be beneficial to support the diagnosis. Out of these, electrocardiography is the most important and commonly done investigation in the emergency departments for patients presenting with chest pain and shortness of breath. However, interpreting these patients' electrocardiograms (ECGs) may be a matter of concern and worry. T wave and ST-segment changes are often of interest in the early signs of myocardial ischemia. Despite its incredible sensitivity, ST-segment deviation (elevated or depressed) has a low specificity because it can be seen in a variety of other cardiac and non-cardiac diseases. When ST-segment anomalies are identified, clinicians must consider many additional characteristics (such as risk factors, symptoms, and anamnesis), as well as all other possible diagnoses. All of these scenarios of patients presenting in the emergency department with chest discomfort and shortness of breath showing ST-segment abnormalities can leave a healthcare professional wondering whether to start treatment for acute myocardial infarction, through either the administration of a fibrinolytic agent, exposing patients to both the benefits and risks of fibrinolysis, or invasive coronary angiography. An astute physician may be able to recognize fabricated differential diagnosis mimicking ST-segment elevation myocardial infarction (STEMI) in some situations. Failure to recognize these imposters can result in inefficient resource utilization, which can expose patients to unjustified risk and increased rather than decreased death and morbidity. Since the danger of cerebral hemorrhage from blood thinners is significant, in patient-care scenarios, in order to rule out percutaneous coronary intervention (PCI), a thorough assessment of the ECG is essential to consider diseases other than acute myocardial infarction, especially the ones that are non-cardiac in origin. The goal of this narrative review is to give an overview of the significant disorders that are non-cardiac in origin that can mimic an ST-segment elevation myocardial infarction (STEMI).