Key result
Increased QT dispersion was associated with arrhythmic events in patients with dilated cardiomyopathy (76 vs 60 ms; P=0.03), but its clinical utility is limited by large overlap between groups.
Why the study?
Does QT dispersion predict arrhythmic events in patients with idiopathic dilated cardiomyopathy?
Cohort (n=207)
Does QT dispersion predict arrhythmic events in patients with idiopathic dilated cardiomyopathy?
Although QT dispersion is increased in IDC patients with arrhythmic events, its clinical utility for risk stratification is limited due to significant overlap with patients without events.
Answers are grounded in this paper and cite their sources.
QT dispersion should not yet guide arrhythmic risk stratification in dilated cardiomyopathy; leaves open its incremental value in prospective multivariable models.
QT dispersion was determined from the 12-lead standard ECGs from 107 patients with idiopathic dilated cardiomyopathy (IDG) and compared to QT dispersion measurements in 100 healthy age and sex matched controls. QT dispersion, rate corrected QT dispersion and adjusted QTc dispersion were significantly greater in patients with IDC compared to controls. During a prospective follow-up of 13 +/- 7 months, arrhythmic events, defined as sustained VT, VF, or sudden death, occurred in 12 (11%) of 107 study patients with IDC. QT dispersion was increased in patients with arrhythmic events compared to patients without arrhythmic events during follow-up (76 +/- 17 vs 60 +/- 26 ms; P = 0.03). Differences in QTc dispersion and adjusted QTc dispersion between patients with and without arrhythmic events, however, failed to reach statistical significance. Thus, although QT dispersion was increased in patients with IDC and arrhythmic events during follow-up, its clinical usefulness for risk stratification appears to be very limited due to the large overlap of QT dispersion among patients with and without arrhythmic events.
No takes yet. Share an insight, caveat, or question.
Grimm et al. (1996) conducted a cohort in Idiopathic dilated cardiomyopathy (n=207). QT dispersion vs. Healthy controls / Patients without arrhythmic events was evaluated on QT dispersion (ms) in patients with vs without arrhythmic events (p=0.03). Increased QT dispersion was associated with arrhythmic events in patients with dilated cardiomyopathy (76 vs 60 ms; P=0.03), but its clinical utility is limited by large overlap between groups.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: