The acute event in posterior myocardial infarction may be preceded by chest pain that becomes more prolonged and intense progressively and is accompanied by fatigability, malaise or no cardiovascular symptoms. The chest pain is intense, lasts for more than 30- 60 minutes, is located in the retrosternal area and may radiate to the jaw, neck, epigastrium, left shoulder, arm or the inter- scapulovertebral region, in which case, aortic dissection must be considered in the differential diagnosis. The pain is classically described as squeezing, burning, aching, tight, crushing or sharp. Symptoms most usually occur early in the morning, due to sympathetic hyperactivity [1] or after intense effort or distress that causes increased myocardial oxygen demand. Depending on the dimensions of the infarcted area, patients may present with low cardiac output symptoms, such as lightheadedness, syncope, sweating, dyspnea. Associated signs include anxiety, arrhythmia, nausea and vomiting (especially if the inferior wall of the left ventricle is also involved), cough and wheezing. The clinical picture allows, to some degree, outcome prediction, based on risk scores: TIMI (Thrombolysis In Myocardial Infarction) and GRACE (Global Registry of Acute Coronary Events) [2] [3].

Clinical examination may reveal cutaneous pallor or cyanosis, diaphoresis, tachycardia (or bradycardia, in cases where an atrioventricular block coexists), various atrial or ventricular arrhythmias, unequal peripheral pulses (if aortic dissection is present), hypertension (or hypotension, if the pump function is severely impaired), fever [4], new heart murmurs (indicating papillary muscle dysfunction or ventricular septum rupture). Right heart failure signs (jugular distension, peripheral edema, hepatomegaly, pulmonary rales) may appear if the infarcted area has ruptured. This can lead to pericardial bleeding, compression of the right ventricle, and an early death.

Posterior myocardial infarction is not an isolated event, but a progression of an inferolateral infarction. This implies that a large portion of the left ventricle is impaired and early diagnosis is imperative [5] [6].

The electrocardiogram is a reliable method for cardiac ischemia diagnosis, but posterior myocardial infarction is not represented directly on the classical 12 lead recording [7]: horizontal ST depression with tall R and T waves in leads V1-V3 and R/S>1 in V2 [8]. Leads V7-V9 show the classical aspect of ST elevation and Q waves. The ST elevation is usually small, with 0.5 mm being enough to establish the diagnosis because of the increased distance between the posterior leads and the heart. 30% of posterior myocardial infarction patients also develop an atrioventricular ischemic block [9].

After the clinical evaluation and electrocardiogram have raised suspicion of a posterior myocardial infarction, blood tests and echocardiographic evaluation are necessary. Blood workup should include cardiac troponins I or T [10], total creatine kinase and its MB isoenzyme, B-type natriuretic peptide- useful for risk stratification [11], complete blood cell count, lipid profile and complete biochemistry (creatinine, potassium, glucose, lactate dehydrogenase, arterial blood gasses). Cardiac biomarkers should be evaluated in a dynamic manner.

Echocardiography establishes the dimension of the infarction, preexisting abnormal motion areas, the presence of complications: septum, wall or papillary muscle rupture, aneurysms, pericardial effusion or tamponade, etc.

Once the diagnosis is clear, a coronary artery angiography should be performed, with both diagnostic (to establish which artery is occluded and at which level) and therapeutic (emergency angioplasty) intent. If angioplasty is impossible, coronary angiography can establish, based on the status of the peripheral arterial bed, if coronary artery bypass is possible. Multidetector computed tomography coronary angiography is used in acute situations to determine the urgency of treatment and to detect myocardial ischemia in patients without confirmatory findings on ECG or with cardiac markers [12] [13].

The treatment of posterior myocardial infarction is similar to other types of heart attacks. Immediate management includes administering oxygen, aspirin, and nitroglycerin to relieve symptoms and improve blood flow. Reperfusion therapy, such as percutaneous coronary intervention (PCI) or thrombolytic therapy, is critical to restore blood flow to the affected area. Long-term management involves lifestyle changes, medications like beta-blockers, ACE inhibitors, and statins, and possibly cardiac rehabilitation.

The prognosis for patients with posterior myocardial infarction depends on the extent of the heart muscle damage and the timeliness of treatment. Early intervention can significantly improve outcomes and reduce the risk of complications, such as heart failure or arrhythmias. With appropriate treatment and lifestyle modifications, many patients can lead a normal life, although they may require ongoing medical supervision.

Posterior myocardial infarction is primarily caused by a blockage in the coronary arteries that supply blood to the heart's posterior wall. This blockage is often due to atherosclerosis, a condition where fatty deposits build up in the arteries. Risk factors include high blood pressure, high cholesterol, smoking, diabetes, obesity, and a sedentary lifestyle. Genetic factors and a family history of heart disease can also contribute.

Posterior myocardial infarctions are less common than other types of heart attacks, accounting for approximately 3-11% of all myocardial infarctions. They are often underdiagnosed due to their atypical presentation and the limitations of standard diagnostic tools. PMI can occur in individuals of any age but is more prevalent in older adults and those with risk factors for coronary artery disease.

In posterior myocardial infarction, the blockage of blood flow leads to ischemia, a condition where the heart muscle is deprived of oxygen. This results in damage or death of the heart tissue in the posterior wall of the left ventricle. The lack of blood supply triggers a cascade of biochemical events that can lead to cell death and impaired heart function if not promptly treated.

Preventing posterior myocardial infarction involves managing risk factors for coronary artery disease. This includes maintaining a healthy diet, engaging in regular physical activity, avoiding smoking, and controlling conditions like hypertension, diabetes, and high cholesterol. Regular medical check-ups and adherence to prescribed medications can also help reduce the risk of heart attacks.

Posterior myocardial infarction is a less common type of heart attack affecting the back wall of the heart. It presents with atypical symptoms, making diagnosis challenging. Prompt recognition and treatment are crucial for improving outcomes. Prevention focuses on managing risk factors for coronary artery disease through lifestyle changes and medical management.

If you or someone you know experiences symptoms like chest pain, discomfort in the upper back, neck, or jaw, shortness of breath, or nausea, it is important to seek medical attention promptly. These could be signs of a heart attack, including a posterior myocardial infarction. Early diagnosis and treatment can significantly improve recovery and reduce the risk of complications. Maintaining a healthy lifestyle and managing risk factors are key to preventing heart attacks.

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