Effect of Remifentanil on the Tpeak-Tend Interval During Electroconvulsive Therapy

QT interval dispersion, which reflects the regional heterogeneity of ventricular repolarization, increases during electroconvulsive therapy (ECT). Tpeak-Tend (TpTe) is considered a new marker of the transmural dispersion of ventricular repolarization (TDR). This study aimed to evaluate the effect of remifentanil on TpTe during ECT.

Forty-two patients who were scheduled to undergo ECT with American Society of Anesthesiologists physical status I or II randomly received 0.1 μg/kg remifentanil (group R: n = 21) or saline (group C: n = 21). After the induction of general anesthesia, we measured the TpTe, TpTe/QT, TpTe/QTc, TpTe/RR, TpTe/√RR and TpTe/³√RR every minute during ECT (QT: QT interval, QTc: corrected QT interval, RR: RR interval). Statistical analysis was performed using two-way analysis of variance (ANOVA).

Immediately (T0) and 1 min (T1) after electrical stimulation, the RRs (group C: T0; 654.2 ± 145.9 ms, T1; 657.3 ± 114.8 ms, group R: T0; 849.6 ± 249.3 ms, T1; 885.4 ± 213.6 ms, p < 0.05) were significantly increased, while systolic (group C: T0; 177.1 ± 35 mmHg, group R: T0; 129 ± 27.2 mmHg, p < 0.05) and diastolic blood pressures (group C: T0; 107.1 ± 22.4 mmHg, T1; 101.3 ± 23.2 mmHg, group R: T0; 75.4 ± 19.3 mmHg, T1; 80.6 ± 18.3 mmHg, p < 0.05) were significantly decreased in group R compared to group C. The TpTe/RR was significantly lower at T1 in group R compared to group C (group C: 101.5 ± 28.2, group R: 76.8 ± 21.8, p < 0.05). However, there was no significant difference in TpTe, TpTe/QT, TpTe/QTc, TpTe/√RR or TpTe/3√RR between the two groups throughout the study.

Pretreatment with remifentanil suppressed the increase of TpTe/RR after electrical stimulation. Our results imply that remifentanil may lead to a decrease in TDR during ECT.

This trial was registered with the University Hospital Medical Information Network (registration number: UMIN000051958).