Key Points: A QRS duration greater than 120 ms reflects delayed or abnormal ventricular depolarization. A wide QRS may be chronic and benign in context, or it may be the…
A 44-year-old man with severe cardiomyopathy, an LVAD, chronic amiodarone therapy, and an AICD presents with palpitations. His ECG shows a regular wide-complex tachycardia, but the rate is only 135….
A 71-year-old man presents with shortness of breath, and his ECG is initially read as a junctional rhythm. On later review, it is even mistaken for atrial fibrillation. But the…
Key Points: Don’t trust the ECG machines automated interpretation. Confirm the rhythm yourself. Start with the ventricles (R–R pattern), then the atria (P waves), then the AV relationship (PR behavior/P:QRS)….
Key Points: Never accept the machine’s rate blindly. Confirm it yourself as ECG computer interpretations are frequently inaccurate. Verify paper speed and gain first (default 25 mm/s, 10 mm/mV). Name…
Key Points: Clinical Context: A single normal 12-lead ECG in the emergent setting does not exclude all life-threatening conditions such as early occlusion MI/ACS, PE, tamponade, or aortic catastrophe. Do…
Key Points: Do not trust a computer read of “normal” without your own review. Computer interpretation is especially unreliable for subtle or early ischemia, including hyperacute T waves, minimal ST…
A 72-year-old man presents with chest pain and shortness of breath. His ECG shows sinus rhythm with LVH, mild inferior ST elevation, and lateral ST-T abnormalities that some interpret as…
A 60-year-old man presents with chest pain that seems a little better after belching, but his clinician is not reassured. The initial ED ECG shows subtle ST-segment abnormalities, the computer…
Key Points: RAE reflects increased right atrial size or pressure load and is usually a marker of underlying pulmonary or right-sided cardiac disease. The classic ECG clue is a tall,…
Key Points: Life Savers are the can’t-miss ECGs. These patterns may reflect immediately life-threatening ischemic, electrical, mechanical, obstructive, toxicologic, or metabolic emergencies. This hub is built for rapid action. Use…
Key Points: Use a consistent ECG routine. In acute care, a repeatable approach reduces misses and helps you recognize dangerous patterns faster. Prioritize life threats first. Instability, malignant rhythms, occlusion…
A 68-year-old man has syncope, then has a second syncopal episode while lying still on a stretcher during evaluation at an outpatient clinic. He is sent emergently to the ED….
Key Points: Anterior T wave inversion in V1-V3 is not synonymous with “anteroseptal ischemia.” The differential includes ACS, right heart strain, conduction/structural disease, and normal variants. In acute care, the…
A 49-year-old man arrives with palpitations and chest discomfort. The monitor shows an irregular, wide-complex tachycardia with varying morphology and rates nearing 250 to 300 bpm. The team debates polymorphic…
Key Points: Read the QRS before you read the ST segment or T wave. Ventricular depolarization shapes repolarization. Narrow QRS usually reflects normal His-Purkinje conduction. Wide QRS suggests abnormal ventricular…
Key Points: Pre-excitation means an accessory pathway allows atrial impulses to reach the ventricle without traversing the AV node, producing early ventricular activation. A delta wave is the defining ECG…
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…
Key Points: Short QT Syndrome (SQTS) is a rare condition characterized by a shortened QT interval on the ECG, increasing the risk of atrial and ventricular arrhythmias, including sudden cardiac…
Key Points: Definition and measurement: The P wave is atrial depolarization. Measure duration from initial deflection to return to baseline and amplitude from baseline to peak. Normal values: Duration <120…