24 August 2009
MedWire News: T-wave morphology parameters independently predict
mortality in the general population, a study from Finland reveals.
The prognostic value of T-waves relates specifically to cardiovascular mortality
and seems to be gender specific, report Kimmo Porthan, from Helsinki University
Central Hospital, and fellow investigators in the journal Heart Rhythm.
The team assessed the associations of electrocardiogram (ECG) QT interval and
four T-wave morphology parameters with all-cause and cardiovascular mortality in
5917 adults enrolled in the Finnish population-based Health 2000 Study.
Over a mean follow-up of 5.9 years, 335 participants died, including 131 from
cardiovascular causes.
In multivariate analysis in men, the T-wave morphology parameters principal
component analysis (PCA) ratio and T-wave morphology dispersion (TMD) were
independent predictors of all-cause and cardiovascular mortality. Above-median
TMD was associated with the greatest risk, at a 4.4-fold increased risk for
cardiovascular death versus below-median TMD.
In women, total cosine R-to-T was independently associated with cardiovascular
mortality, while T-wave residuum (TWR) was associated with both all-cause and
cardiovascular mortality. The greatest risk was associated with above-median
TWR, at a 2.2-fold increased risk for cardiovascular death.
Heart rate-corrected QT interval was not an independent predictor of mortality
in multivariable analysis, however.
“The study shows that, unlike ECG QT intervals, T-wave morphology parameters
contain predictive value for mortality in the general population,” commented
Porthan.
He added: “The study results deepen our existing knowledge about the predictive
value of several ECG repolarization parameters and will potentially help plan
future clinical trials assessing cardiac repolarization.”
MedWire is an independent clinical news service provided by Current Medicine
Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd;
2009
Heart Rhythm 2009; 6: 1202–1208