Predictive value of QT interval dynamicity for sudden death in patients with idiopathic dilated cardiomyopathy
10.3760/cma.j.issn.0253-3758.2010.12.010
- VernacularTitle:QT间期动态性在扩张型心肌病猝死风险预测中的价值
- Author:
Ming-Wei BAO
1
;
Tuan-Tuan TAN
;
Sheng-Bo YU
;
Kui CHEN
;
Cong-Xin HUANG
Author Information
1. 武汉大学人民医院
- Keywords:
Cardiomyopathy,dilated;
Electrocardiography;
Death,sudden,cardiac
- From:
Chinese Journal of Cardiology
2010;38(12):1093-1097
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the predictive value of QT interval dynamicity for sudden death in patients with idiopathic dilated cardiomyopathy ( DCM ). Methods Fifty-five patients with DCM ( DCM group) and 27 healthy subjects (Control group, Con) were enrolled. Investigations included history collection, clinical examination, echocardiography, electrocardiogram and 24 h ambulatory electrocardiogram. Following indexes were determined: left ventricle end diastolic dimension ( LVEDD), left ventricle ejection fraction (LVEF), QT dispersion (QTd), SDNN, the slope of QT/RR plots of the linear regression, ventricular premature beats (VPB) and non-sustained ventricular tachycardia (NSVT). Primary end point for patients with DCM was all cause death. Results LVEDD, QTd, VPB/24 h, NSVT/24 h,QTe/RR slope and QTp/RR slope were significantly higher while LVEF and SDNN were significantly lower in DCM group than in Con group (all P＜0.05). LVEDD, LVEF, QTd, SDNN, QTe/RR slope and QTp/RR slope were significantly different among DCM sudden death group, DCM non sudden death group and Con group (P ＜ 0. 05 ). LVEF, SDNN, QTe/RR slope and QTp/RR slope were significantly different between DCM sudden death and non sudden death group (P ＜ 0. 05). LVEF, QTd, VPB/24 h, QTe/RR slope and QTp/RR slope were significantly different between DCM with NSVT and DCM without NSVT group (P ＜0. 05). The sudden death rate of DCM patients with QTe/RR slope ≥ 0. 210 was significantly higher than DCM patients with QTe/RR slope ＜ 0. 210 (54. 5% vs. 21.1%, P ＜ 0. 05 ). Sudden death rate of QTp/RR slope≥0. 190 was also higher than those ＜0. 190 (52. 2% vs. 21.9%, P ＜0. 05). The sudden death rate of DCM patients with both LVEF≤35% and NSVT + was 62. 5%. Combining QTe/RR≥0. 210 with NSVT + or LVEF ≤ 35%, the sudden death rates were 62. 5% or 66.7%. Combining QTp/RR ≥0. 190 with NSVT + or LVEF≤35%, the sudden death rates were 66. 7% or 61.5%. Combining QTe/RR ≥0. 210 or QTp/RR ≥0. 190 with NVST + and LVEF≤35%, the sudden death rates were 77. 8% or 70. 0%. Conclusions High QT/RR slope is a risk factor for sudden death of DCM patients. QT/RR slope is a useful predictor for sudden death in DCM patients either independently or combined with NSVT or LVEF.
