Differential Diagnosis for ST Elevations in Leads II, III with Right Bundle Branch Block
Single Most Likely Diagnosis
- Acute Pericarditis: This condition is characterized by inflammation of the pericardium, which can cause ST elevations in multiple leads, including II and III, without reciprocal changes. The presence of a right bundle branch block does not necessarily alter this diagnosis, as pericarditis can occur independently of bundle branch blocks.
Other Likely Diagnoses
- Early Repolarization: This is a benign condition that can mimic ST elevations, particularly in leads II, III, and aVF. It's often seen in healthy individuals and may not be associated with any symptoms.
- Myocardial Infarction (MI) with Right Bundle Branch Block: Although less likely due to the absence of reciprocal changes, an MI cannot be entirely ruled out, especially if the patient has risk factors or other signs suggestive of ischemia.
Do Not Miss Diagnoses
- Acute Coronary Syndrome (ACS): Despite the absence of reciprocal changes, ACS, including MI, must be considered due to its high morbidity and mortality. The presence of a right bundle branch block can sometimes mask or alter the typical ECG signs of ischemia.
- Pulmonary Embolism (PE): A large PE can cause ST elevations in the inferior leads (II, III, aVF) and may also lead to right bundle branch block due to increased pressure on the right heart. This diagnosis is critical to consider due to its potential for severe consequences if missed.
Rare Diagnoses
- Brugada Syndrome: This genetic disorder can cause ST elevations in leads II and III, among other ECG abnormalities. However, it typically presents with a distinctive pattern of ST elevation in leads V1-V3 and is less likely given the specific lead involvement mentioned.
- Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): This rare condition affects the right ventricle and can lead to various ECG abnormalities, including ST elevations and bundle branch blocks. It's an important consideration in patients with unexplained arrhythmias or structural heart disease.