QRS and QTc interval prolongation in the prediction of long-term mortality of patients with acute destabilised heart failure.
OBJECTIVE
To quantify the prognostic utility of QRS and QTc interval prolongation in patients presenting with acute destabilised heart failure (ADHF) to the emergency department (ED).


METHODS
Prospective cohort study among patients enrolled in the B-Type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) study. QRS and QT intervals were measured in 173 consecutive patients with ADHF. QT interval was corrected using the Bazett formula. The primary end point was all-cause mortality during the 720-day follow-up.


RESULTS
QRS interval was prolonged (> or =120 ms) in 27% of patients, and QTc interval was prolonged (> or =440 ms) in 72% of patients. Baseline demographic and clinical characteristics were comparable in patients with normal and prolonged QRS or QTc intervals. A total of 78 patients died during follow-up. Interestingly, the 720-day mortality was similar in patients with prolonged and normal QTc (44% vs 42%, p = 0.546), but was significantly higher in patients with prolonged QRS interval than in those with normal QRS (59% vs 37%, p = 0.004). In Cox proportional hazards analysis, prolonged QRS interval was associated with a nearly twofold increase in mortality (HR 1.94, 95% CI 1.22 to 3.07; p = 0.005). This association persisted after adjustment for variables routinely available in the ED.


CONCLUSIONS
Prolonged QRS interval, but not prolonged QTc interval, is associated with increased long-term mortality in patients with ADHF.
Breidthardt
Tobias
T
Department of Internal Medicine, University Hospital Basel, Petersgraben 4, Basel, Switzerland.
Christ
Michael
M
Matti
Miriam
M
Schrafl
Delia
D
Laule
Kirsten
K
Noveanu
Markus
M
Boldanova
Tujana
T
Klima
Theresia
T
Hochholzer
Willibald
W
Perruchoud
André P
AP
Mueller
Christian
C
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D004812:Epidemiologic Methods; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008133:Long QT Syndrome / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis