RT Journal Article
SR Electronic
T1 Baseline Q waves as a prognostic modulator in patients with ST-segment elevation: insights from the PLATO trial
JF Canadian Medical Association Journal
JO CMAJ
FD Canadian Medical Association
SP 1135
OP 1142
DO 10.1503/cmaj.111683
VO 184
IS 10
A1 Siha, Hany
A1 Das, Debraj
A1 Fu, Yuling
A1 Zheng, Yinggan
A1 Westerhout, Cynthia M.
A1 Storey, Robert F.
A1 James, Stefan
A1 Wallentin, Lars
A1 Armstrong, Paul W.
YR 2012
UL http://www.cmaj.ca/content/184/10/1135.abstract
AB Background: Baseline Q waves may provide additional value compared with time from the onset of symptoms in predicting outcomes for patients with ST-segment elevation. We evaluated whether baseline Q waves superseded time from symptom onset as a prognostic marker of one-year mortality in patients with ST-segment elevation acute coronary syndrome. Our study was derived from data from patients undergoing primary percutaneous coronary intervention within 24 hours in the PLATelet inhibition and patient Outcomes trialMethods: Q waves on the baseline electrocardiogram were evaluated by a blinded core laboratory. We assessed the associations between baseline Q waves and time from symptom onset to percutaneous coronary intervention with peak biomarkers, ST-segment resolution on the discharge electrocardiogram, and one-year all-cause and vascular mortality.Results: Of 4341 patients with ST-segment elevation, 46% had baseline Q waves. Compared to those without Q waves, those with baseline Q waves were older, more frequently male, had higher heart rates, more advanced Killip class and had a longer time between the onset of symptoms and percutaneous coronary intervention. They also had higher one-year all-cause mortality than patients without baseline Q waves (baseline Q waves: 4.9%; no baseline Q waves: 2.8%; hazard ratio [HR] 1.78, 95% confidence interval [CI] 1.29–2.45, p < 0.001). Complete ST-segment resolution was greatest and all-cause mortality lowest among those with symptom onset three hours or less before percutaneous coronary intervention and no baseline Q waves. After multivariable adjustment, baseline Q waves, but not time from symptom onset, were associated with a significant increase in all-cause mortality (adjusted HR 1.42, 95% CI 1.10–2.01, p = 0.046) and vascular mortality (adjusted HR 1.58, 95% CI 1.09–2.28, p = 0.02). Interpretation: The presence of baseline Q waves provides useful additional prognostic insight into the clinical outcome of patients with ST-segment elevation. Clinical Trials.gov registration no. NCT00391872 See related commentary by Mercuri and colleagues on page 1125 and at www.cmaj.ca/lookup/doi/10.1503/cmaj.120624