Cimetidine-dobutamine interaction?

The report describes a patient during induction of anaesthesia for coronary artery by-pass grafting, in whom the infusion of dobutamine at a rate of 5 micrograms.kg-1.min-1 resulted in unanticipated severe hypertension. The exaggerated response may be attributed to cimetidine--dobutamine interaction.     

Role of norepinephrine in development of short-term myocardial hibernation

AIM: To investigate the role of norepinephrine in the development of short-term myocardial hibernation. METHODS: Hearts were removed from rats and set up as isometrically beating or short-term hibernation models. The hearts were perfused with modified Krebs-Henseleit buffer under a controlled perfusion pressure. The myocardial ultrastructure was examined, and the content of ATP, phosphocreatine, and glycogen in myocardium, the extent of myocyte apoptosis, and the amount of Bcl-2 and Bax products were determined after 120-min ischemia assessed by TUNEL and immunocytochemistry. RESULTS: There was no significant difference between the reserpinized hearts and the NS control group with respect to heart function, myocardial ultrastructure, ATP, phosphocreatine, or glycogen content, myocyte apoptosis, or amount of Bax or Bcl-2 products. However, relative to the normal saline group, in the norepinephrine-treated hearts, heart function, and myocardial ultrastructure deteriorated significantly, apoptosis and amount of Bax product increased significantly, and the ATP, phosphocreatine, and glycogen content decreased significantly, as did the amount of Bcl-2 product. CONCLUSION: Myocardial norepinephrine does not contribute to the development of short-term hibernation, but that exogenous NE can induce progressive decreases in coronary flow and cardiac performance, which might result from the increases in apoptosis and necrosis. Norepinephrine may be an important factor in the deterioration of myocardial structure and function during hibernation, and that anti-adrenergic treatment may be helpful for the development and sustainment of short-term myocardial hibernation.     

Spontaneous coronary artery dissection during a dobutamine stress echocardiography

We report a case of a spontaneous dissection of the right coronary artery during a dobutamine stress echocardiography (DSE) study in a middle-aged male. Our patient experienced a severe retrosternal pain of abrupt onset during the DSE study, whereas EKG was evident of significant ST segment elevation in II, III, avF, and V5-V6 leads, followed by an accelerated idioventricular rhythm. Immediate coronary angiogram revealed a minor dissection of the distal part of the right coronary artery.     

多巴酚丁胺多普勒超声心动图负荷试验对冠心病的诊断价值

用多普勒超声心动图观察３３例左室舒张功能正常的冠心病人和３８例正常人静脉滴注多巴酚丁胺前后左室舒张功能各指标的变化。用药后左室舒张功能各指标两组间差异有显著性（Ｐ值＜０．０５），用药前后左室舒张功能各主要指标变化量两组间差异非常显著（Ｐ值＜０．０００１），多巴酚丁胺多普勒超声心动图负荷试验诊断冠心病的敏感性、特异性、准确性分别为：１００％、９７．４％、９８．６％。因此认为该试验是诊断冠心病特异、敏感而安全可行的方法。     

低剂量多巴酚丁胺超声心动图检测心肌梗塞后可逆的功能障碍

应用低剂量多巴酚丁胺负荷超声心动图（LDDSE）试验对21例心肌梗塞患者梗塞区心肌功能障碍的可逆性进行研究。可逆的可能障碍是指室壁运动得到改善。结果表明静息超声心动图（RE）至LDDSE时室壁运动得分指数（WMSI）在急性心肌梗塞（AMI）从1．83±0．32下降到1．45±0．19（P＜0．01）；而陈旧性心肌梗塞（OMI）从1．96±0．35下降到1．70±0．20（P＜0．05）。RE时336个节段中有82个节段室壁运动异常，LDDSE时46（56．1％）个节段室壁运动改善，7（8．5％）个节段室壁运动明显改善。提示心肌梗塞后梗塞区有存活心肌细胞成分。LDDSE试验能够简便准确地检测心肌梗塞后梗塞区心肌功能障碍的可逆性。