Effect of Dapagliflozin on Electrocardiographic Parameters in Type 2 Diabetes Patients: DAPA - ECG Study

Effect of Dapagliflozin on the QT and QTc Interval

In the intervention group (dapagliflozin), 12-lead electrocardiograms (ECGs) were performed during designated outpatient visits, with the initial baseline recording conducted at visit 1 (day 0) and the subsequent recording at the final visit, approximately 90 days after the study began. The ECGs were obtained using Micromed electronic equipment, configured with a paper speed of 25 mm/s and an amplitude of 10 mm/mV, ensuring standardized measurements. The ECG intervals were manually measured using Wincardio software (version 11.1.0.0). The secondary outcomes, the QT and corrected QT (QTc) intervals, were assessed to evaluate the effect of dapagliflozin. These intervals were analyzed by comparing the two time points (baseline and follow-up). All ECGs were reviewed by an independent external examiner, ensuring objectivity and reliability in the interpretation of the study data.

Time frame: 90 days

Effect of Dapagliflozin on the TpTe/QT ratio

To evaluate the effect of dapagliflozin on the TpTe/QT ratio, an electrocardiographic marker of arrhythmogenesis that reflects the degree of heterogeneity in myocardial repolarization. The TpTe interval, measured as the time from the peak of the T wave to the end of the T wave, and the TpTe/QT ratio, calculated by dividing the TpTe interval by the QT interval, were assessed at baseline (visit 1, day 0) and follow-up (final visit, approximately 90 days later). Prolonged TpTe and TpTe/QT intervals are associated with a higher risk of sudden cardiac death (SCD) in various cardiac conditions, including hypertrophic cardiomyopathy and long QT syndrome, making them valuable prognostic markers. In this study, 12-lead ECGs were recorded using Micromed electronic equipment (configured at a paper speed of 25 mm/s and amplitude of 10 mm/mV), and intervals were manually measured with Wincardio software (version 11.1.0.0).

Time frame: 90 days

Effect of Dapagliflozin on the J-Tpeak Interval

The J-Tp interval (JTp), an important marker of delays in the early phase of the action potential, was measured from the J point to the peak of the T wave (Tp) on 12-lead electrocardiograms (ECGs). Baseline ECG recordings were conducted at visit 1 (day 0), while follow-up recordings were obtained approximately 90 days later at the final visit. All ECGs were recorded using Micromed electronic equipment, standardized with a paper speed of 25 mm/s and an amplitude of 10 mm/mV. Manual measurements of the JTp interval were performed using Wincardio software (version 11.1.0.0). This parameter was assessed to evaluate the effect of dapagliflozin on early ventricular repolarization dynamics, providing valuable insights into potential delays in the initial phase of the cardiac action potential and contributing to the overall understanding of its impact on cardiac electrophysiology.

Time frame: 90 days

Effect of Dapagliflozin on the QT interval dispersion (QTd)

QT interval dispersion (QTd), a marker of spatial heterogeneity in ventricular repolarization, was calculated as the difference between the longest (QTmax) and shortest (QTmin) QT intervals measured on 12-lead electrocardiograms (ECGs). Baseline ECG recordings were taken at visit 1 (day 0), and follow-up recordings were acquired approximately 90 days later at the final visit. The ECGs were obtained using Micromed electronic equipment, configured with a paper speed of 25 mm/s and an amplitude of 10 mm/mV. All interval measurements were manually conducted using Wincardio software (version 11.1.0.0) to ensure precision and standardization. This parameter was analyzed to assess the impact of dapagliflozin on reducing ventricular repolarization dispersion, which has been associated with an increased risk of arrhythmias and sudden cardiac death (SCD) in patients with type 2 diabetes.

Time frame: 90 days

Effect of Dapagliflozin on The QRS-T angle

The QRS-T angle, a vectorcardiographic marker of ventricular repolarization heterogeneity and electrical dyssynchrony, was evaluated using data obtained from 12-lead electrocardiograms (ECGs). Baseline ECGs were recorded at visit 1 (day 0), and follow-up recordings were performed approximately 90 days later at the final visit. The QRS-T angle was calculated by analyzing the electrical axes of the QRS complex and the T wave in the frontal plane leads. These measurements were performed using the MYEKG software, which processed the R and T wave amplitudes in millimeters and calculated the spatial QRS-T angle using a dedicated algorithm available at \[https://pt.my-ekg.com/calculadoras-ecg/calculadora-eixo-eletrico.php\]. The QRS-T angle was categorized into three groups: normal (0 to 105°), borderline (105 to 135°), and abnormal (135 to 180°). This parameter was assessed to determine the impact of dapagliflozin on ventricular electrical heterogeneity

Time frame: 90 days

Effect of Dapagliflozin on the Heart rate

Heart rate was measured from 12-lead electrocardiograms (ECGs) recorded during designated outpatient visits. Baseline ECG recordings were obtained at visit 1 (day 0), and follow-up ECGs were performed approximately 90 days later at the final visit. The ECGs were recorded using Micromed electronic equipment, standardized with a paper speed of 25 mm/s and an amplitude of 10 mm/mV. Heart rate measurements were automatically calculated by the Wincardio software (version 11.1.0.0) and manually verified when necessary to ensure precision and consistency. This parameter was evaluated to assess the effect of dapagliflozin on overall cardiac rhythm and rate regulation in patients with type 2 diabetes. Independent external examiners reviewed all ECGs to ensure objectivity and reliability in the study data.

Time frame: 90 days