A 63-year-old man presents with shortness of breath. His ECG shows an unusual rhythm with repetitive groups of two beats separated by pauses.
Key Points: Definition: Slow VT refers to ventricular tachycardia occurring at an unusually low ventricular rate, often near or even below the conventional tachycardia threshold. There is no universally accepted…
Key Points: Default assumption: A regular wide-complex tachycardia should be considered VT until another diagnosis is more likely. Rate modifies the differential, not the diagnosis. Typical monomorphic VT is often…
A patient presents with a regular narrow-complex tachycardia. The computerized interpretation identifies sinus tachycardia, and the rhythm appears superficially compatible with that diagnosis when lead II is reviewed. However, closer…
A 69-year-old man presents with chest pain. His ECG is interpreted by the computer as atrial fibrillation, a diagnosis that could significantly alter his evaluation and long-term management. The rhythm…
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…
Key Points: Definition: Atrial fibrillation is a supraventricular arrhythmia characterized by disorganized atrial electrical activity, ineffective atrial contraction, and an irregular ventricular response. ECG diagnosis: Look for an irregularly irregular…
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: T wave alternans is beat-to-beat alternation in T wave amplitude, polarity, or morphology with otherwise stable P waves and QRS complexes. Visible T wave alternans is a warning…
Key Points: The Bix Rule is a bedside ECG clue for atrial flutter with 2:1 conduction. If an apparent “P wave” sits exactly halfway between 2 QRS complexes in a…
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: 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….
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: Junctional tachycardia is an uncommon supraventricular tachycardia arising from the AV junction, usually due to enhanced automaticity rather than reentry. It is usually a regular narrow-complex tachycardia, although…
Key Points: Continuous-flow LVADs can mask cardiovascular collapse. Patients may remain awake during sustained VT or even VF because the pump can provide temporary flow. Treat the rhythm and the…
Key Points: Unstable bradyarrhythmias cause poor perfusion which can rapidly progress to shock, irreversible organ injury, or cardiac arrest. Priority: Do not treat the heart rate alone. Treat clinical instability….
Key Points: Junctional rhythms arise from the AV junction, usually the AV node or proximal His bundle, when the sinus node slows, fails, or impulses do not reach the ventricles…
An 81-year-old woman presents with lightheadedness and marked bradycardia. Her ECG shows more P waves than QRS complexes, but the mechanism is not immediately clear. The key question is whether…
Key Points: SVT in bedside emergency medicine usually refers to a rapid regular tachycardia arising above the ventricles, most commonly AVNRT, AVRT, or atrial tachycardia. Most SVTs are regular narrow-complex…