ObjectivePatients with chronic obstructive pulmonary disease (COPD) often have abnormal ECGs. Our aim was to separate the effects on ECG by airway obstruction, emphysema and right ventricular (RV) afterload in patients with COPD.MethodsA cross-sectional study was performed on 101 patients with COPD without left heart disease and 32 healthy age-matched controls. Body mass index (BMI) was measured, and pulmonary function tests, ECG, echocardiography and right heart catheterisation (only patients) were performed. Variables were grouped into (1) airway obstruction by FEV% (percentage of forced expiratory volume)_predicted, (2) emphysema by residual volume/total lung capacity and residual volume (percent of predicted) and (3) RV afterload by mean pulmonary pressure, artery compliance, vascular resistance and RV wall thickness.ResultsIn multivariate regression analysis, emphysema correlated negatively to R+S amplitudes in horizontal and frontal leads, RV/left ventricle (LV) end-diastolic volume ratio to horizontal amplitudes and BMI negatively to frontal amplitudes. Increased airway obstruction, RV afterload and BMI correlated with horizontal QRS-axis clockwise rotation. Airway obstruction, RV afterload, RV/LV end-diastolic volume ratio and BMI correlated to the Sokolow-Lyon Index for RV, and RV afterload negatively to Sokolow-LyonIndex for LV. Several classical ECG changes could, however, not be ascribed to specific mechanisms.ConclusionsIn COPD, the various pathophysiological mechanisms modify the ECG differently. Increased airway obstruction and RV afterload mainly increase the Sokolow-Lyon Index for RV mass and associate with clockwise rotation of the horizontal QRS-axis, whereas emphysema reduces the QRS amplitudes. BMI is an equally important determinant for the majority of the ECG changes.

Low HRR was independently associated with increased risk of CV death in apparently healthy, middle-aged men. The predictive impact of HRR on CV death risk was, however, confined to unfit men.

BackgroundChronotropic index is a standardized measure of heart rate (HR) increment during exercise that reflects the combined effects of age, resting HR, and physical fitness. Low chronotropic index has been reported to predict disease and death. We tested whether temporal change in chronotropic index over 7 years influenced risk of cardiovascular death through up to 28 years.Methods and ResultsChronotropic index was calculated ([achieved maximal HR−resting HR]/[age‐predicted maximal HR−resting HR]) after a symptom‐limited bicycle ECG exercise test in 1420 healthy men at 2 examinations 7 years apart, in 1972 and 1979. Events of cardiovascular death were registered by manual scrutiny of all participants’ hospital charts and the Norwegian Cause of Death Registry. The participants were divided into quartiles of temporal change in chronotropic index, with quartile one having the most negative value. Cox proportional hazard regression models were used to estimate risks and adjusted for classical cardiovascular risk factors. Incidence of cardiovascular death was 310 (22%) during median of 21 years of follow‐up. After multivariable adjustment, and comparison with quartile four (mean +0.11), quartiles one (−0.16), two (−0.04), and three (+0.02) were associated with hazard ratios 1.50 (95% CI 1.10–2.05), 1.10 (0.79–1.53), and 1.04 (0.74–1.45) for cardiovascular death. Results remained robust also after exclusion of 31 participants with exercise ECG‐induced signs of coronary ischemia.ConclusionsTemporal reduction in chronotropic index was associated with increased long‐term risk of cardiovascular death and might be a clinically important predictor when assessing risk in healthy individuals over a longer time.