Author + information
- Soner Olmez1,
- Murat Akkoyun2,
- Murat Sahin3,
- Ali Riza Namli4,
- Mehmet Akgüngör2,
- Imran Dirnak2,
- Yalcin Goksugur4,
- Kamile Gul3 and
- Gurkan Acar2
Diabetes mellitus is a chronic multisystemic disease associated with the development of specific long-term organ damage caused by microvascular disease, which is referred to as diabetes complications. The frequency of cardiovascular disease, including sudden cardiac death, ischemic heart disease, systolic or diastolic heart failure, conduction system abnormalities, and arrhythmias is increased in diabetic patients. Recently, several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias and cardiovascular mortality. Although ventricular repolarization was previously evaluated by using T wave and QT interval measurements in patients with DM-1, the novel repolarization indexes Tp-e interval and Tp-e/QT ratio have not been studied in DM-1 patients before. The aim of this study was to evaluate repolarization dispersion measured from a 12-lead surface electrocardiogram (including Tp-e interval and Tp-e/QT ratio) in patients with DM-1.
Fifty patients with DM-1 (19.7±6.6 years) and 35 healthy controls (18.4±5.5 years) were included. Detailed physical and echocardiographic examinations were performed in all subjects. Maximum and minimum QT duration and Tp-e interval were measured from the 12-lead electrocardiogram, and corrected for heart rate. QT dispersion and Tp-e/QT ratio were calculated. These parameters were compared between groups.
Demographic, clinical, echocardiographic, and electrocardiographic data of the sudy group are listed in Table 1. Corrected maximum QT interval and corrected QT dispersion were significantly increased in type 1 diabetes mellitus patients compared to the controls (430.7±29.6 vs 412.6±26.4 and 49.3±22.9 vs 37.3±16.9 ms, p=0.01 and p=0.01, respectively). Novel ventricular repolarization indexes, Tp-e interval and Tp-e/QT ratio were similar between groups (p>0.05).
Our study revealed that when compared to the healthy controls, Tp-e interval and Tp-e/QT ratio were similar in DM-1 over without cardiovascular disease.
|Patients with DM-1 (n=50)||Control group (n=35)||P value|
|Smoking n (%)||6 (12.0)||4 (11.4)||NS|
|Systolic BP (mmHg)||104.2±11.6||102.7±8.6||NS|
|Diastolic BP (mmHg)||68.4±7.1||67.1±5.1||NS|
|Heart rate (beats/min)||85.9±10.8||82.5±9.3||NS|
|LV EDD (mm)||44.3±4.5||45.7±5.1||NS|
|Left atrial dimension (mm)||29.0±4.2||31.2±4.1||NS|
|LV mass index (g/m2)||80.3±19.7||80.3±19.9||NS|
|LV EF (%)||67.6±5.6||67.0±6.3||NS|
|Disease duration (months)||73.8 ± 63.2||-|
DM: Type 1 diabetes mellitus, BMI: Body mass index, BP: Blood pressure, LV EDD: Left ventricular end diastolic diameter, LV: Left ventriculare, EF: Ejection fraction, QTmax: QT maximum, cQTmax: corrected QT maximum, QTmin: QT minimum, cQTmin: corrected QT minimum, QTd: QT dispersion, cQTd: corrected QT dispersion, Tp-e: transmural dispersion of repolarization, cTp-e: corrected transmural dispersion of repolarization, NS Not significant.