Disease relevance of ARBUTAMINE

• Arbutamine detected ischemia more often than exercise with each of the three ischemic end points [1].
• The ability of arbutamine stress to induce myocardial ischemia, detectable by echocardiography, was comparable to that for exercise [2].
• The sensitivity for detecting coronary artery disease ( > or = 50% stenosis) using arbutamine thallium-201 SPECT was 87% (95% for detecting > or = 70% stenoses), and the normalcy rate in the low likelihood group was 90% [3].
• METHODS: Arbutamine was infused (0.5-250 ng/kg/min) in 8 open-chest dogs with critical coronary stenoses that abolished flow reserve [4].
• The most frequent adverse events during arbutamine (n = 36) were dyspnea (5.6%) and tremor (5.6%) [5].

High impact information on ARBUTAMINE

• Arbutamine echocardiography: efficacy and safety of a new pharmacologic stress agent to induce myocardial ischemia and detect coronary artery disease. The International Arbutamine Study Group [2].
• Arbutamine was administered by a novel computerized closed-loop device that measures heart rate and adjusts arbutamine infusion to achieve a selected rate of heart rate increase toward a predetermined limit [3].
• In the 210 patients, the mean increase in heart rate and systolic blood pressure evoked by arbutamine and exercise was 51 and 53 beats/min (p = NS) and 36 and 44 mm Hg (p < 0.0001), respectively [1].
• This study sought to evaluate the efficacy and safety of arbutamine when used in conjunction with thallium-201 single-photon emission computed tomography (SPECT) in a multicenter trial and to compare arbutamine stress and treadmill exercise thallium-201 SPECT for diagnostic sensitivity and myocardial perfusion pattern [3].
• RESULTS: Arbutamine increased mean heart rate, peak positive left ventricular pressure and its first time-derivative, and normal-zone myocardial thickening [4].

Chemical compound and disease context of ARBUTAMINE

• Effects of dobutamine and arbutamine on regional myocardial function in a porcine model of myocardial ischemia [6].

Biological context of ARBUTAMINE

• Arbutamine is delivered by a new computerized drug delivery device that adjusts the rate of drug infusion according to the patient's heart rate response during stress testing [2].
• We conclude that arbutamine simulates some of the physiological responses to exercise, although a number of these responses are less marked than during conventional exercise, in particular cardiac output (oxygen pulse) [7].
• The end-tidal partial pressure of CO(2) [35.1 (S.D. 3. 1) to 30.8 (6.6) mmHg] and the dead space/tidal volume ratio (V(D)/V(T)) [0.37 (0.09) to 0.33 (0.08)] fell significantly during arbutamine infusion, but the respiratory exchange ratio did not change during either protocol [7].
• Oxygen pulse, a marker of stroke volume, did not change significantly after arbutamine, but rose markedly after exercise [arbutamine, 3.9 (1.1) to 3.37 (0.7) ml. min(-1).beat(-1); exercise, 4.7 (1.4) to 16.1 (4.6) ml.min(-1). beat(-1) (P<0.0001 compared with baseline); difference between peak responses: P<0.0001] [7].
• The stress agents may be divided into those that produce primary coronary vasodilation (dipyridamole, adenosine, or adenosine triphosphate) and those that produce secondary vasodilation as a result of increase in myocardial oxygen demand (dobutamine and arbutamine) [8].

Anatomical context of ARBUTAMINE

• In detecting documented coronary artery disease, the sensitivity of arbutamine testing was equal to that of exercise for the electrocardiographic end point of ST segment change alone [1].
• Arbutamine stimulation detects viable myocardium 4 weeks after coronary occlusion [9].
• Moreover, arbutamine stimulated beta3-adrenergic receptors in guinea pig ileum [10].
• In guinea pig trachea, arbutamine and isoproterenol produced a concentration-dependent relaxation that was blocked by propranolol [10].

Associations of ARBUTAMINE with other chemical compounds

• Arbutamine stress thallium-201 single-photon emission computed tomography using a computerized closed-loop delivery system. Multicenter trial for evaluation of safety and diagnostic accuracy. The International Arbutamine Study Group [3].
• A comparison of adenosine and arbutamine for myocardial perfusion imaging [11].
• It is concluded that arbutamine produces similar imaging results compared with standard dobutamine stress with both Tc-99m sestamibi single-photon emission computed tomographic myocardial perfusion imaging and 2-dimensional echocardiography [12].
• Effect of atenolol or metoprolol on arbutamine stress echocardiography in patients suspected of having coronary artery disease [13].
• METHODS AND RESULTS: Twenty-seven patients referred for diagnostic coronary arteriography underwent separate day dipyridamole and arbutamine Tc-99m sestamibi SPECT imaging with simultaneous two-dimensional echocardiography [14].

Gene context of ARBUTAMINE

• The affinity constants (KA) of arbutamine and isoproterenol for cardiac beta1-adrenergic receptors, as determined by competition binding assays, were found to be 7.32 and 6.04, respectively [10].

Analytical, diagnostic and therapeutic context of ARBUTAMINE

• The sensitivity of arbutamine echocardiography was determined in 143 patients who had coronary artery disease documented by coronary angiography [2].
• Among those patients who had both stress test results, the incidence of inducing myocardial ischemia (new or worsening wall motion abnormalities) was 79% (95% confidence interval [CI] 69% to 86%, n = 98) for arbutamine and 77% (95% CI 67% to 85%, n = 98) for exercise echocardiography [2].
• A subset of 69 patients from the catheterization group underwent both arbutamine and exercise stress testing [3].
• Arbutamine stress echocardiography [15].
• Arbutamine stress perfusion imaging in dogs with critical coronary artery stenoses: (99m)Tc-sestamibi versus (201)Tl [4].

References