Johansson Mats, Gao Sinsia A, Friberg Peter, Annerstedt Marita, Bergström Göran, Carlström Jan, Ivarsson Ted, Jensen Gert, Ljungman Susanne, Mathillas Oivind, Nielsen Finn-David, Strömbom Ulf
Department of Clinical Physiology, Sahlgrenska University Hospital, Göteborg, Sweden.
Clin Sci (Lond). 2004 Dec;107(6):583-8. doi: 10.1042/CS20040122.
Patients with CRF (chronic renal failure) are at increased risk of cardiovascular diseases, and 60% of cardiovascular mortality in CRF is attributed to sudden death. Various abnormalities in myocardial repolarization are associated with the risk of ventricular arrhythmia. The aim of this study was to evaluate an index of temporal myocardial repolarization lability, the temporal QTVI (QT variability index), in patients with CRF. ECGs were recorded in 153 patients with CRF on haemodialysis (n=67), continuous ambulatory peritoneal dialysis (n=43) or conservative treatment (n=43) during 30 min of rest. QTVI was calculated as the logarithm of the ratio between the variances of the normalized QT and RR intervals. Age-matched healthy subjects (n=39) were examined for comparison. QTVI was increased by 47% in CRF patients compared with healthy subjects (-0.82+/-0.56 compared with -1.54+/-0.27 respectively; P<0.01). QTVI did not differ among patients on dialysis or conservative treatment, whereas QTVI was elevated further in patients with diabetes compared with non-diabetic CRF patients (-0.56+/-0.54 compared with -0.94+/-0.52 respectively; P<0.01). In a multiple linear regression analysis, diabetes and a history of coronary artery disease were the only independent predictors of QTVI in the CRF population. The present study demonstrates that elevated QTVI in patients with CRF is associated with diabetes and coronary disease. The present findings are important given that repolarization instability may predispose to ventricular arrhythmia and sudden death, events that occur frequently in CRF patients.
慢性肾衰竭（CRF）患者患心血管疾病的风险增加，CRF患者中60%的心血管死亡率归因于猝死。心肌复极化的各种异常与室性心律失常风险相关。本研究的目的是评估慢性肾衰竭患者心肌复极时间变异性指标——QT变异性指数（QTVI）。对153例接受血液透析（n = 67）、持续性非卧床腹膜透析（n = 43）或保守治疗（n = 43）的CRF患者在静息30分钟期间进行心电图记录。QTVI计算为标准化QT间期与RR间期方差之比的对数。选取年龄匹配的健康受试者（n = 39）进行对照检查。与健康受试者相比，CRF患者的QTVI增加了4７%（分别为 - 0.82±0.56与 - 1.54±0.27；P < 0.01）。透析患者或接受保守治疗的患者之间QTVI无差异，而糖尿病患者的QTVI较非糖尿病CRF患者进一步升高（分别为 - 0.56±0.54与 - 0.94±0.52；P < 0.01）。在多元线性回归分析中，糖尿病和冠心病史是CRF人群中QTVI的唯一独立预测因素。本研究表明，CRF患者QTVI升高与糖尿病和冠心病有关。鉴于复极化不稳定可能易患室性心律失常和猝死，而这些事件在CRF患者中经常发生，目前的研究结果具有重要意义。
