Abstract: | Objective To evaluate the clinical significance of QT dis persion (QTd, QTcd) in dilated cardiomyopathy (DCM). Methods QTd and QTcd were measured on simultaneously recording 12-lead electrocardiograms ( ECGs) in 60 DCM patients and cormpared with 60 healthy subjects. Results The values of QTd and QTcd in DCM were significantly higher than those in control group ( P<0. 01 ). With subgroup analysis, QTd and QTcd in patients uith cardiac sudden death (CSD) were longer than those in survivors and those died of progressive heart failure ( P<0. 05), patients with ventricular tachycardia (VT) or with severe heart failure than those without (compared uith patients with ventricular premature beats [V PB], P<0.05, compared with patients without ventricular arrhythmia [VA], P<0. 01) or with mild heart failure (P<0. 01). The values of QTd and QTcd in patients with VPB were greater than those in patients without VA( P< 0. 05). There were significant differences in the rates of VT, CSD and heart failure between the groups of QTd> 110 ms and QTd≤110 ms(P<0. 01 or P<0.05), in contrast to ejection fraction (EF) and fractional shortening (FS)( P>0.05). Conclusion The values of QTd and QTcd increased in DCM patients were susceptive index for monitoring maligant VA in DCM, also important prognostic markers of CSD. QTd was correlated with NY HA functional class but not with EF and FS. |