Prognostic importance of change in QRS duration over time associated with left ventricular dysfunction in patients with congestive heart failure: the DIAMOND study.
BACKGROUND
The prognostic importance reported for QRS duration in patients with heart failure (HF) and left ventricular dysfunction varies. No prior study has investigated the prognostic importance of change in QRS duration over time.


RESULTS
The Danish Investigations and Arrhythmia ON Dofetilide (DIAMOND) study randomized 1518 patients with HF to dofetilide (class III antiarrhythmic drug) or placebo. All patients had left ventricular dysfunction. QRS duration was systematically measured at randomization and every 3 months after that. During 10 years of follow-up, 1324 (89%) of the patients died. QRS duration increased from baseline by 1.36 ms (95% confidence interval [CI]: -0.26 to -2.98; P = .1) after 12 months and by 3.65 ms (CI: 0.22-7.07; P = .04) after 24 months. QRS duration measured at baseline was not of prognostic significance after multivariable adjustment (adjusted hazard ratio [HR] 1.01, CI: 0.99-1.04; P = .2 per 10-ms increment in QRS duration). The adjusted relative risk associated with a 10-ms increase in QRS duration over time was 2% (HR 1.02, CI: 1.01-1.04; P = .03). A 10-ms increment in QRS 12 months after randomization was associated with a HR of 1.05 (CI: 1.00-1.09; P = .03).


CONCLUSIONS
In patients with left ventricular dysfunction and HF, QRS duration increased over time and the increase was associated with increasing mortality.
Fosbøl
Emil Loldrup
EL
The Heart Centre, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark. ELF@heart.dk
Seibaek
Marie
M
Brendorp
Bente
B
Torp-Pedersen
Christian
C
Køber
Lars
L
D000368:Aged; D000369:Aged, 80 and over; D003718:Denmark / Q000453:epidemiology; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology*