A 51-year-old truck driver presents to the ED after a brief syncopal episode at a rest stop. It is the middle of summer, his truck’s air conditioning is not working,…
Key Points: Not a PE diagnosis: S1Q3T3 is classically associated with pulmonary embolism, but it is neither sensitive nor specific enough to diagnose or exclude PE. Think acute right heart…
Key Points: The ECG cannot rule in or rule out PE: No single ECG finding is sufficiently sensitive or specific to diagnose or exclude acute pulmonary embolism. A Normal ECG…
Key Points: The ECG can provide an early warning of severe RV strain: No ECG finding defines high risk PE, but marked or evolving signs of acute RV pressure overload…
A 69-year-old woman presenting with sepsis gets the following ECG for tachycardia while febrile and shivering. The baseline is poor, atrial activity is difficult to identify, and the computer interpretation…
A 56-year-old man presents with 1 week of concerning chest pain and shortness of breath. His ECG does not meet conventional STEMI criteria, but it shows subtle ST-segment abnormalities in…
A 34 year old man presents with acute chest pain radiating to the left arm associated with diaphoresis. He has hyperlipidemia and a family history of early coronary disease. The…
Key Points: The Barcelona Criteria are ECG criteria proposed to identify acute myocardial infarction in patients with LBBB. Core problem: LBBB causes expected secondary ST-T changes, so standard STEMI millimeter…
Key Points: Aslanger pattern is an OMI pattern that can identify acute inferior occlusion despite not meeting traditional STEMI criteria. The key finding is ST segment elevation isolated to lead…
Key Points: LBBB does not exclude acute coronary occlusion. LBBBs produce abnormal depolarization and expected secondary ST-T changes, which can mask or mimic ischemia. Acute occlusion MI can still be…
A 72-year-old man is brought to the ED after witnessed cardiac arrest. Bystander CPR was started quickly, EMS found a nonshockable rhythm, epinephrine was given, and ROSC was achieved. Forty…
Key Points: The first post-ROSC ECG is essential but imperfect. Obtain it immediately, but interpret it in context. Global ischemia, defibrillation, acidosis, hypothermia, vasopressors, artifact, and severe metabolic derangements can…
Key Points: Persistent ST elevation after ROSC remains a guideline-supported indication for emergency coronary angiography. The 2025 ACC/AHA/ACEP/NAEMSP/SCAI ACS guideline recommends emergency angiography for patients after cardiac arrest with suspected…
Key Points: Stable post-arrest patients without ST elevation should not go to reflex immediate cath solely because cardiac arrest occurred. Randomized trials in OHCA patients without ST elevation have not…
Key Points: Pediatric arrest is usually respiratory, hypoxic, or shock-related, not primary coronary occlusion. The ECG still matters because it can reveal reversible metabolic, toxicologic, structural, inflammatory, or inherited electrical…
A 72-year-old man is brought to the ED after a witnessed out-of-hospital cardiac arrest. Bystander CPR is started quickly, EMS finds a non-shockable rhythm, and ROSC is achieved after one…
A 70-year-old woman with CHF, COPD, intermittent atrial fibrillation, chronic pain medication use, and recent poor intake develops sudden dyspnea at rest and is found somnolent and bradycardic in the…
Key Points: A spectrum, not a single rhythm: Sinus node dysfunction includes inappropriate sinus bradycardia, sinus pauses or arrest, SA exit block, chronotropic incompetence, and alternating atrial tachyarrhythmias with bradycardia….
Key Points: Definition: Sinoatrial, or SA, exit block occurs when the sinus node generates an impulse that fails to conduct into the surrounding atrial tissue. The blocked impulse produces no…
Key Points: Definition: Sinus arrest occurs when the sinus node temporarily fails to generate an impulse. This produces an absence of the expected P wave and its associated QRS complex….