Pfisterer M, Glaus L, Burkart F
Circulation. 1983 Feb;67(2):291-301. doi: 10.1161/01.cir.67.2.291.
To compare acute effects of nitroglycerin (0.8 mg sublingually), nifedipine (5 ng/kg/min i.v.) and metoprolol (0.15 mg/kg i.v.) on normal, ischemic and scarred myocardial segments in man, we performed simultaneous hemodynamic and radionuclide measurements of left ventricular functions. Sixteen patients with isolated left anterior descending (LAD) disease were studied at rest and during exercise. Nine patients had angina and exercise-induced ischemia (LAD stenosis) and seven patients had previous transmural myocardial infarction and no ischemic changes during thallium imaging (LAD occlusion). The effects of the drugs on regional ejection fraction of the involved anteroseptal region and the normal posterolateral area were compared. Global ejection fraction at rest did not change after nitroglycerin, increased after nifedipine and decreased after metoprolol. In patients with ischemia, the exercise ejection fraction improved after all drugs due to increased regional ejection fraction in ischemic segments: i.e., a regional antiischemic effect evidenced by improved regional function could be demonstrated with all three agents. Regional ejection fraction increased from 35.8 +/- 19.5% to 66.2 +/- 15.2% (+/- SD) after nitroglycerin (p less than 0.001), to 61.7 +/- 8.7% after nifedipine (p less than 0.001), and to 48.4 +/- 7.0% after metoprolol (p less than 0.01). In regions of myocardial scar, regional ejection fraction was not changed after any drug. In normal areas, regional ejection fraction remained unchanged after nitroglycerin and nifedipine, but decreased after metoprolol. Despite similar antiischemic effects of all three drugs, underlying hemodynamic mechanisms were quite different and may provide a rationale for combined forms of treatment. These results may help to select optimal drug combinations to improve myocardial performance in patients with chronic ischemic heart disease.
为比较硝酸甘油（舌下含服0.8毫克）、硝苯地平（静脉注射5纳克/千克/分钟）和美托洛尔（静脉注射0.15毫克/千克）对人体正常、缺血和瘢痕化心肌节段的急性影响，我们同时进行了左心室功能的血流动力学和放射性核素测量。对16例单纯左前降支（LAD）病变患者在静息和运动时进行了研究。9例患者有胸痛和运动诱发的缺血（LAD狭窄），7例患者既往有透壁性心肌梗死且在铊显像时无缺血改变（LAD闭塞）。比较了这些药物对受累前间隔区域和正常后外侧区域局部射血分数的影响。静息时的整体射血分数在硝酸甘油用药后未改变，硝苯地平用药后升高，美托洛尔用药后降低。在有缺血的患者中，所有药物用药后运动射血分数均改善，原因是缺血节段的局部射血分数增加：即，所有三种药物均能证明因局部功能改善而产生的局部抗缺血作用。硝酸甘油用药后局部射血分数从35.8±19.5%增加至66.2±15.2%（±标准差）（p＜0.001），硝苯地平用药后增加至61.7±8.7%（p＜0.001），美托洛尔用药后增加至48.4±7.0%（p＜0.01）。在心肌瘢痕区域，任何药物用药后局部射血分数均未改变。在正常区域，硝酸甘油和硝苯地平用药后局部射血分数保持不变，但美托洛尔用药后降低。尽管所有三种药物的抗缺血作用相似，但其潜在的血流动力学机制差异很大，这可能为联合治疗形式提供理论依据。这些结果可能有助于选择最佳药物组合以改善慢性缺血性心脏病患者的心肌功能。
