The ECG Blog
In sinus rhythm, atrial activation starts at the SA node and spreads downward, giving us upright P waves in the inferior leads (II, III, aVF) that pre...
Atrial fibrillation (AF) gives an irregularly irregular ventricular response, so the usual single-cycle methods (300/large-boxes, 1500/small-boxes) ar...
Premature atrial contractions (PACs) are a common finding on ECG and are usually benign. But sometimes a PAC arrives at the AV node when it is still r...
Second-degree type I AV block, also known as Mobitz I or Wenckebach, is typically characterized by a progressive prolongation of the PR interval follo...
Fusion beats are one of the hallmark findings that support the diagnosis of ventricular tachycardia (VT)ā€”particularly in the case of monomorphic VT. T...
When confronted with a wide QRS complex that appears unexpectedly on an ECG, one of the key clinical challenges is to determine whether it's due to a ...
Bundle branch blocks (BBBs) occur when there's a delay or interruption in the electrical conduction through either the right or left bundle branch of ...
Electrical alternans is a fascinating ECG phenomenon typically associated with large pericardial effusionā€”but it is not pathognomonic for it. This bea...
Left ventricular hypertrophy (LVH) is most often recognized on ECG by increased QRS voltageā€”tall R waves in left-sided leads and deep S waves in right...
Atrial fibrillation (AF) is marked by chaotic atrial activity that can drive the ventricles at dangerously high rates. While the atria may be firing a...
AV Nodal Reentry Tachycardia (AVNRT) is one of the most common types of paroxysmal supraventricular tachycardia (PSVT), frequently encountered in the ...
Complete heart blockā€”or third-degree AV blockā€”is a feared complication of ST segment elevation myocardial infarction (STEMI), particularly when the in...