Effect Of Nicorandil On ECG Parameters In Patients With Unstable Angina Pectoris

IntroductionThe purpose of this study was to investigate the short-term effects of intracoronary injection combined with intravenous injection of nicorandil on the changes of ECG in patients with unstable angina(UA)who received percutaneous coronary intervention(PCI).MethodsThis study is a single-center,prospective and self-controlled clinical study.The criteria of the selected subjects were as below: From January 2019 to April 2019,patients with UA admitted to the Second Hospital of Tianjin Medical University for selective PCI treatment.The selected patients were divided into three groups:(1)Group A: control group;(2)Group B: short-term application of nicorandil;(3)Group C: long-term application of nicorandil.Each group of UA patients received routine blood biochemical examination,echocardiography,coronary angiography and selective PCI treatment.The administration methods of each group were as follows:(1)Group A: Normal saline(1ml/Kg.h)was continuously pumped into the vein immediately after PCI,lasting for 6 hours;(2)Group B: 10 ml of normal saline containing 0.5mg nicorandil was injected into the coronary artery during PCI treatment.Within 6 hours after PCI,nicorandil was continuously pumped into the vein at the rate of 2mg/h for 6 hours.The total amount of nicorandil in Group B was 12 mg calculated.(3)Group C: During PCI operation,10 ml of normal saline containing 0.5mg of nicorandil was injected into the coronary artery.Within 24 hours after PCI treatment,nicorandil was continuously pumped into the vein at the rate of 2mg/h for 24 hours.The total amount of nicorandil was 48 mg calculated in Group C.In the whole study,12-lead ECG was performed before and after 24 hours in nicorandil treatment.Results1.According to the criteria of inclusion and exclusion,63 patients with UA were enrolled in this study.There were 23 patients in Group A,including 14 male patients,with an average age of 63.43±12.55 years;20 patients in Group B,including 12 male patients,with an average age of 66.45±8.06 years;20 patients in Group C,including 15 male patients,with an average age of 65.80±9.49 years.2.Among three groups of different treatment,no significant difference was found in baseline characteristics,including hypertension history,diabetes history,smoking and drinking history,laboratory tests and echocardiographic indicators(P > 0.05).3.In control group,there was no significant difference in ECG indexes before and after saline injection.In nicorandil treatment group,QT interval dispersion and Tp-e interval were significantly shorter than those before nicorandil treatment,and the difference was statistically significant.In Group B,QT interval dispersion decreased from 43.95 ± 11.16 ms to 30.85 ± 8.63 ms,and Tp-e interval decreased from 99.50 ±15.71 ms to 80.50 ± 20.38ms(P<0.05).In Group C,QT interval dispersion decreased from 38.25 ± 13.40 ms to 28.80 ± 9.74 ms,and Tp-e interval decreased from 98.25 ± 11.72 ms to 86.50 ± 8.12ms(P <0.05).4.After combining two nicorandil groups(Group B and C)and comparing them with control group(Group A),the QT interval dispersion and Tp-e interval in nicorandil groups decreased significantly.In nicorandil groups,QT interval dispersion decreased from 41.10 ± 15.51 ms to 29.82 ± 9.15 ms,and Tp-e interval decreased from 98.87 ± 13.70 ms to 83.50 ± 15.61ms(P <0.05).Conclusions1.In UA patients undergoing selective PCI,intracoronary injection combined with intravenous continuous infusion of nicorandil could shorten QT interval dispersion and Tp-e interval.2.The treatment of nicorandil for 6 and 24 hours could shorten QT interval dispersion and Tp-e interval in UA patients undergoing selective PCI.