Comparison Of The Characteristics Of Action On The Heart Rate Of Different β1-adrenoceptor Blockers

Comparison of the characteristics of action on the heart rateof differentβ1-adrenoceptor blockersObjective:To compare the onset time, efficacy, interindividual variability, efficacy duration, adverse drug reactions between metoprolol, atenolol and bisoprolol and to discover the characteristics of action on the heart rate of these differentβ1-adrenoceptor blockers, so as to deepen the understanding of the role ofβ1-blocker characteristics and to provide the basis for a reasonable clinical choice.Methods:Totally 300 patients(171 male,129 female; mean age of 67years) with heart rate(HR)=66/min and blood pressure(BP)=100mmHg who were scheduled for Multi-slice Spiral Coronary Computered Tomographic Angiography (CTA), were randomly assigned to receive treatment with metoprolol(25mg to 100mg), atenolol(25mg to 100mg) and bisoprolol(5mg to 20mg) during March 20,2009 to July 11,2009. The rapider the HR was, patients taken more drug. The clinical data of all the patients were record:age, gender, hypertension, diabetes, hypercholesteremia, smoking, drinking, symptoms(chest tightness, chest pain, palpitations), height and weight immediately at admission. HR, blood pressure and adverse drug reaction(ADR) were monitored at an interval of 15mins after the drug was buceally taken until 240mins later. Then compared and analysed the time-consuming before the HR decreases to=65/min, the range of the change of the HR, the dispersion of the range of the change of the HR, the range of the change of the blood pressure and the adverse drug reactions between metoprolol, atenolol and bisoprolol groups.Results:During 240 mins, HR(heart rate) and BP(blood pressure) of 300 patients were monitored,and 62,92,95 patients reach the target HR(65bpm).The data of age, gender, hypertension, diabetes, hypercholesteremia, smoking, drinking, symptoms(chest tightness, chest pain, palpitations), height, weight and the results of CTA were not significantly different between the three groups (P>0.05).Compared with the other two groups, HR of patients with lower resting HR (=75bpm) decreased to 65bpm after a longer period of time in bisoprolol group(P<0.01), but there was no significantly difference between patients with higher resting HR (=76bpm). Compared with the patients with higher resting HR (=76bpm) in other two groups, HR of much less patients ever decreased to 65bpm in metoprolol group(P <0.01), but there was no significantly difference between patients with lower resting HR (=75bpm).In metoprolol group,the range of changes of HR was statistically less than other two groups (P<0.01), and dispersion of the range of changes of HR was the highest.The range of changes of HR were similar between other two groups, and so was the dispersion of it. Compared with metoprolol group, lowered average HR could maintain much longer in other two groups. The range of changes of SBP and DBP were similar between three groups.No intolerant ADRs happened.In metoprolol group, much more minor ADRs,such as dizziness and headache happened.Conclusion:1.Metoprolol,atenolol and bisoprolol all can be effective and safe in decreasing HR. The effect on decreasing HR of atenolol is equal to that of bisoprolol, which is much stronger than metoprolol.2.Dispersion of effect on decreasing HR of metoprolol is more obviously than atenolol and bisoprolol.3. Atenolol and bisoprolol can act much longer.