RT Journal Article SR Electronic T1 Dynamics of QT interval from rest to peak exercise among COPD patients JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P2115 VO 44 IS Suppl 58 A1 Russell Franks A1 Afrodit Boutou A1 Divya Mohan A1 Lilian Mantziari A1 Tom Wong A1 Nicholas Hopkinson A1 Michael Polkey YR 2014 UL http://erj.ersjournals.com/content/44/Suppl_58/P2115.abstract AB BackgroundCardiovascular involvement is frequent in Chronic Obstructive Pulmonary Disease (COPD), with autonomic dysfunction a recognized feature. However, the dynamics of QT interval, a known marker of autonomic dysfunction, from rest to peak exercise in COPD patients has not yet been investigated.AimTo examine the changes in QT and heart-rate corrected QT (QTc) intervals from rest to peak exercise in a population of stable COPD outpatients and of healthy controls.MethodsProspectively collected data on COPD patients and healthy controls who underwent spirometry and maximum cardiopulmonary exercise testing with a continuous 12-lead ECG recording, were retrospectively analyzed. Distribution of variables was assessed with Shapiro-Wilk test and group comparisons were conducted utilizing the paired samples T-test or Wilcoxon rank test, as appropriate. Level of p<0.05 was considered significant.ResultsThe study population consisted of 143 patients (63.6% male; 62.8±7.4 years old; FEV1%=32.3±14) and 18 age and gender-matched controls. Among controls, the QT interval shortened (361.1±39.1 vs 270±27.7, p<0.001), while QTc increased (396.4±24.4 vs. 422.7±32.9, p<0.001) from rest to peak exercise. Among COPD patients, QTc interval did not increase (406.2±25.8 vs 411.9±34.2, p=0.53). QT interval shortened (333.4±34.7 vs. 299±32, p<0.001), but its absolute change was smaller, when compared to controls. Medications known to prolong QT interval did not impact on QT dynamics.ConclusionCOPD patients demonstrate a different exercise response; QTc interval does not increase, and QT shortening is about 30% of that seen in healthy controls.