Clinical Trial To Assess The Safety And Efficacy Of Intravenous Administration Of Nicorandil In Patients With Unstable Angina Pectoris

BACKGROUND: Nicorandil is constructed by the N-(2-hydroxyethyl) nicotinamide and part of the organic nitrate, which is the first K+-ATP channel opener used in clinical. In the structure of nitrates, it causes the relaxation of the vascular smooth muscle, but in a few areas it is different from the traditional nitrates. As a K+-ATP channel opener, Nicorandil increases the outcome of K+ from the cells and inhibit the income of Ca2+, so it results in vasodilation and increases coronary blood flow, this dual role reduces both the preload and afterload of the heart. The guideline of 2006 ESC unstable angina shows that nicorandil is a drug of improving the symptoms as recommended levelⅠ. Many animal and clinical tests have proved the useful role of nicorandil in unstable angina and myocardial infarction.PURPOSE: To study the effect of the use of intravenous continuous nicorandil on patients with unstable angina and evaluate the efficacy and safety of nicorandil and nitroglycerin.METHOD: The 61 patients who are diagnosed as the unstable angina and suffered the recurrent angina within 48 hours in the hospital's cardiovascular unit from May 2006 to May 2007 were divided into the test group that nicorandil group (n = 31) and the control group that nitroglycerin group (n = 30),and using intravenous continuous for 48 hours, surveying the first 24-hour Holter and the resting electrocardiogram after 6, 12, 24, 36, 48 hours, monitoring the blood pressure and heart rates after 1, 2, 6, 12, 24, 36, 48 hours, and the adverse reaction at any time, examining the urine ,Liver and kidney function both before and after the test. RESULTS:1. The test include 61cases,divided into two groups ,31cases in the nicorandil group and 30 cases in the nitroglycerin group. There are no statistically significant(P> 0.05) between the two groups of the population on the group information, medical history, vital signs and indicators of efficacy, that shows that the balance and comparability of the two groups are good.2. Main effect indicators: the efficiency on the improvement of the resting electrocardiogram with the use of nicorandil shows better than that with the use of the nitroglycerin, and there is statistically significant differences (P = 0.043) in the 48 hours between the two groups , so the nicorandil is better than nitroglycerin in the efficiency.3. Secondary effects indicators: During the treatment, 90.3% (28/31) of the patients in nicorandil group don't suffer from angina again, and 76.6% (23 / 30) of ones in the nitroglycerin group don't, but there was no significant difference between the two groups. There are no statistical difference between the two groups on the number of attacks and the duration of the angina who suffer from angina again. It suggests that nicorandil are better than nitroglycerin.4. The myocardial oxygen consumption of the nicorandil group is higher than nitroglycerin group only from 1 to 6 hours on the blood pressure, heart rate and myocardial oxygen demand (HR×SBP), but there is no angina attack again in the corresponding time, and not statistically differences in all time points.5. There are 7 times drug-related adverse reactions during the test, including five cases 16.12% in the nicorandil group which show from mild to moderate headache and two cases 6.67% in the nitroglycerin group which express as the low blood pressure, all of the adverse reactions release within six hours. There are no hypotension cases of the nicorandil group but 2 cases in the nitroglycerin group, so that nicorandil is safer than nitrog- lycerin.6. There is no significant effective on the blood routine, urine routine and renal function in both of the two groups. The liver function in both groups increase. The reason is considered the joint application of statin drugs, infections and the use of antibiotics.CONCLUSION: The continuous intravenous use of nicorandil on the unstable angina shows more efficient on resting electrocardiogram and better control of clinical symptoms, and a lower trend in the incidence of low blood pressure.