QRS fragmentation
Also written as: fQRS — fragmented QRS
The presence of additional spikes or notches within the QRS complex on electrocardiogram, indicating abnormal ventricular depolarization.
Full Definition
QRS fragmentation (fQRS) represents heterogeneous ventricular conduction caused by myocardial scarring, fibrosis, or ischemia. It appears as additional R or S waves, or notching of the R or S wave in two contiguous leads. Fragmented QRS complexes are associated with increased risk of ventricular arrhythmias and sudden cardiac death, particularly in patients with structural heart disease. The finding is commonly seen in patients with prior myocardial infarction, cardiomyopathy, or infiltrative cardiac diseases, and may indicate areas of slow conduction that could serve as substrate for reentrant arrhythmias.
Usage
Usage note: Requires narrow QRS complexes (<120 ms) to be clinically significant.
In Context
- "The ECG showed QRS fragmentation in leads II, III, and aVF, consistent with inferior wall scarring." — ECG interpretation report
- "New QRS fragmentation appeared following the patient's myocardial infarction, indicating areas of conduction delay." — Cardiology follow-up note