Killer Differentials

Latest

Must-Know Differential Diagnoses (DDx) Hub

Key Points: A differential diagnosis is the structured process of considering multiple possible conditions that could explain a patient’s symptoms and ECG findings. This hub is a curated index of…

Short QT Interval: DDx

Key Points: Short QT Interval: A QT interval is considered short when the corrected QT (QTc) interval is less than 350 ms. A short QT interval on the ECG can…

Prolonged QT Interval: DDx

Key Points: The QT interval reflects the time it takes for total ventricular depolarization and repolarization (Q wave onset to T wave end). QT prolongation increases the risk of torsades…

ST Elevation: DDx

Key Points: ST elevation describes an ECG finding, not a diagnosis. It reflects abnormal ventricular repolarization and can arise from ischemic, structural, metabolic, electrical, or extracardiac processes. Occlusion MI is…

Diffuse ST Elevation: DDx

Key Points: ST-segment elevation (STE) is an ECG finding, not a diagnosis. Multiple ischemic and non-ischemic processes can produce STE. Diffuse STE is often non-ischemic, in contrast to the regional…

STEMI vs Early Repolarization: DDx

Key Points: Early repolarization (ER) is a common, benign ECG pattern that most often appears in young, healthy patients. It can closely resemble acute anterior STEMI, creating a high-risk diagnostic…

STEMI vs LV Aneurysm: DDx

Key Points: LV aneurysm pattern is a post MI scar pattern with persistent ST elevation in the prior infarct territory, usually with pathologic Q waves and a stable, non evolving…

ST Elevation in aVR: DDx

Key Points: ST elevation (STE) in aVR with diffuse ST depression elsewhere most often reflects global subendocardial ischemia, not focal transmural infarction. High-risk coronary disease is one cause, not the…

STEMI Mimics: DDx

Key Points: ST elevation is a pattern, not a diagnosis. STEMI represents one cause of ST elevation and requires correlation with ECG morphology, distribution, evolution, and clinical context. Most ED…

STEMI vs Severe Hyperkalemia: DDx

Key Points: Severe hyperkalemia is a true ECG chameleon. It can produce ST elevation, wide QRS complexes, axis shifts, and conduction blocks that closely mimic STEMI or ventricular tachycardia. New…

STEMI vs Takotsubo Cardiomyopathy: DDx

Key Points: Takotsubo (stress) cardiomyopathy is a transient, non-ischemic LV dysfunction—classically apical ballooning with basal hyperkinesis—often after emotional or physical stress. Presentation mimics occlusion MI (chest pain, ECG changes, elevated…

ST Depression in V1-V4: DDx

Key Points: Do not reflexively label ST depression in V1–V4 as “anterior ischemia/NSTEMI.” In ACS symptoms, posterior OMI is a major concern when the depression is most prominent in V1–V3…

Ventricular Tachycardia (VT) Mimics

Key Points: Initial Assumption: Any wide (QRS >120 ms), regular tachycardia should be considered ventricular tachycardia (VT) until clearly proven otherwise. VT Characteristics: VT generally has a ventricular rate of…

Clumped or Grouped Beats: DDx

Key Points: Clumped or grouped beats can cause irregular rhythms, often leading to misdiagnosis as atrial fibrillation. Misdiagnosing atrial fibrillation may lead to inappropriate rate/rhythm control or unnecessary anticoagulation in…

Large T Wave: DDx

Key Points Large T waves are not a single diagnosis. Clinical context and associated ECG findings determine whether the cause is benign, metabolic, or a high-risk OMI pattern. The most…

Poor R Wave Progression (PRWP): DDx

Key Points PRWP is a pattern, not a diagnosis. Use clinical context and compare with prior ECGs before acting. Practical definition: R in V3 less than 3 mm or a…

Must-Know Syncope: DDx

Key Points: Syncope and the ECG: Syncope is a transient loss of consciousness and postural tone, characterized by rapid onset, brief duration, and spontaneous recovery without medical intervention. Cardiac syncope…

Acute Chest Pain: DDx

Key Points In patients presenting with acute chest pain, identifying life-threatening conditions is essential. Use a systematic ECG approach alongside clinical context to evaluate for high-risk diagnoses that require immediate…

Tall R wave in V1: DDx

Key Points Normal expectation: In V1, the S wave is typically larger than the R wave. A tall or dominant R wave (R/S > 1) is abnormal and should prompt…

Tall R wave in aVR: DDx

Key Points Normal expectation: In aVR, the QRS is usually negative (deep S wave). A dominant or tall R wave (R > S) is abnormal and should prompt investigation. Mechanism:…

Free Content

Jump on our email list for free tips and insights delivered to your inbox monthly. No spam - just quick pearls and ECG education.

Categories
Loading...