Key Points Tension pneumothorax is a clinical diagnosis—ECG changes are nonspecific but can provide supportive evidence in the right context. Electrical changes are primarily due to mechanical effects of air…
Key Points Aortic dissection or aneurysm can produce ischemic‑appearing ECGs due to coronary malperfusion, most often right coronary involvement causing inferior changes. Pseudo‑infarction patterns, ST‑deviation, and conduction blocks can occur…
Key Points ECG red flags: Bradycardia, PR/QRS/QT prolongation, flattened P, peaked T, → AV block/asystole at higher levels. Neuromuscular: Hyporeflexia → weakness → respiratory depression → coma. Immediate countermeasure (severe/symptomatic):…
Key Points Terminology: WPW pattern = ECG evidence of pre-excitation without symptoms. WPW syndrome = pattern plus symptomatic tachyarrhythmia (e.g., AVRT, pre-excited AF). Mechanism: An atrioventricular accessory pathway (e.g., Kent;…
Key Points: Complexity of ACS: Arteries can spontaneously reperfuse or re-occlude. Understanding early ECG patterns of early acute ischemia can help detect dynamic changes and prompt rapid interventions. ECG Pattern…
Key Points Continuous-flow LVADs can mask shock: patients may talk through VT/VF because pump flow maintains some perfusion. Treat the rhythm, not the appearance. First steps in any unstable LVAD…
Key Points Rare, inherited ventricular arrhythmia triggered by adrenergic stress during exertion or emotion. Classically presents in children or adolescents with syncope or cardiac arrest despite a normal resting ECG…
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…
Key Points Always get a 12-lead ECG in altered or confused patients. The ECG is a great triage and risk stratification tool and can reveal reversible, life-threatening causes when history…
Key Points A Simple Yet Powerful Tool: With just a piece of paper and some ink, the ECG can be the earliest clue to life-threatening metabolic disease when labs are…
Key Points Artifact is a common source of misdiagnosis for serious arrhythmias such as polymorphic ventricular tachycardia (PVT), torsades de pointes, or ventricular fibrillation (VF). Always correlate the ECG findings…
Key Points Monomorphic ventricular tachycardia (MMVT) is the most common sustained VT. It shows a single, uniform QRS morphology throughout. Classified as sustained if lasting > 30 seconds or associated…
Key Points Definition: A negative deflection after the T wave (a true U wave) that is ≥0.5 mm deep in a lead where the T wave is upright. Why it…
Key Points A QRS duration greater than 120 ms indicates abnormal ventricular depolarization. A wide QRS can signal conditions that range from benign to immediately life-threatening. Developing a focused differential…
Key Points Not all ST elevation is ischemia. The most common mimics at the point of care are atrial activity riding on the ST segment, motion or lead artifact, early…
Key Points ECG alone cannot reliably distinguish VT from SVT-aberrancy in many cases. Use ECG features to rule in VT, not to exclude it. Default: treat regular WCT as VT…
Key Points BiVT is a regular wide-complex VT with beat-to-beat alternation of QRS axis and/or bundle-branch pattern (often alternating RBBB/LBBB or 180° frontal-plane axis shift). Most common cause is severe…
Key Points Idiopathic monomorphic VT arising from the right ventricular outflow tract. Most patients have no structural heart disease; catecholamine and cAMP-mediated triggers are common. Classic ECG pattern: LBBB morphology…
Key Points: Hypokalemia slows ventricular repolarization and alters the T–U complex before it triggers arrhythmias. Progressive pattern: T-wave flattening → prominent U waves → T–U fusion with apparent QT prolongation;…
Key Points Severe hypokalemia can produce dramatic ECG changes that may be mistaken for acute coronary syndromes. It can also precipitate life-threatening arrhythmias, including torsades de pointes and ventricular tachyarrhythmias…