89457
document
Comparison of arbutamine and exercise echocardiography in diagnosing myocardial ischemia . Arbutamine is a new catecholamine designed for use as a pharmacologic stress agent . This study compared the sensitivity of arbutamine with symptom-limited exercise to induce echocardiographic signs of ischemia . Arbutamine was administered by a computerized closed-loop delivery system that controls the infusion rate of arbutamine toward a predefined rate of heart rate increase and maximum heart rate limit . Beta blockers were stopped > or = 48 hours before both tests . Stress was stopped for intolerable symptoms , or clinical , electrocardiographic or echocardiographic signs of ischemia ( new or worsening wall motion abnormality ) , target heart rate ( > or = 85 % age predicted maximum heart rate ) , or plateau of heart rate response . Thirty-seven patients were entered into the study ( 35 arbutamine and exercise , 1 arbutamine only , 1 exercise only ) , of which 30 had angiographic evidence of coronary artery disease ( > or = 50 % lumen diameter narrowing ) . Rate-pressure product increased significantly in response to both stress modalities ( p < 0.001 ) and was significantly greater with exercise ( 11,308 +/- 2,443 ) than with arbutamine ( 9,486 +/- 2,479 , p < 0.001 ) . The time to maximum heart rate was longer during arbutamine stress echocardiography than during exercise testing ( 17.3 +/- 9.4 versus 9.3 +/- 4.2 minutes , respectively , p < 0.001 ) . There were more patients with interpretable echo data for arbutamine ( 82 % ) than for exercise ( 67 % ) . Sensitivity for recognition of myocardial ischemia was 94 % ( 95 % confidence interval 70 % to 100 % ) and 88 % ( 95 % confidence interval 62 % to 98 % ) , respectively . The most frequent adverse events during arbutamine ( n = 36 ) were dyspnea ( 5.6 % ) and tremor ( 5.6 % ) . Two arbutamine stress tests were discontinued due to arrhythmias : 1 patient had premature atrial and ventricular beats , and the other had premature atrial contractions and atrial fibrillation . Arrhythmias were well tolerated and resolved without sequelae . In conclusion , the sensitivity of arbutamine to induce echocardiographic signs of ischemia was similar to that of exercise despite a lower rate-pressure product . Arbutamine was well tolerated and provides a reliable alternative to exercise echocardiography .
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Intervention_Pharmacological
arbutamine
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Intervention_Physical
exercise echocardiography
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Intervention_Pharmacological
Arbutamine
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Intervention_Pharmacological
arbutamine
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Intervention_Physical
symptom-limited exercise
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Intervention_Pharmacological
Arbutamine
89464
Intervention_Pharmacological
arbutamine
89465
Intervention_Pharmacological
arbutamine
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Intervention_Physical
exercise
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Intervention_Physical
exercise
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Intervention_Pharmacological
arbutamine
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Intervention_Physical
exercise
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Intervention_Pharmacological
arbutamine
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Intervention_Physical
exercise
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Intervention_Pharmacological
arbutamine
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Intervention_Pharmacological
arbutamine
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Intervention_Pharmacological
arbutamine
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Intervention_Physical
exercise
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Intervention_Pharmacological
Arbutamine
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Intervention_Physical
exercise echocardiography
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Outcome_Physical
echocardiographic signs of ischemia .
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Outcome_Physical
Rate-pressure product
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Outcome_Physical
time to maximum heart rate
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Outcome_Physical
Sensitivity for recognition of myocardial ischemia
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Outcome_Adverse-effects
adverse events
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Outcome_Adverse-effects
dyspnea
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Outcome_Adverse-effects
tremor
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Outcome_Adverse-effects
arrhythmias :
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Outcome_Adverse-effects
premature atrial and ventricular beats
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Outcome_Physical
premature atrial contractions and atrial fibrillation . Arrhythmias were well tolerated and resolved
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Outcome_Physical
echocardiographic signs of ischemia
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Outcome_Physical
rate-pressure product .
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Outcome_Other
well tolerated and provides a reliable alternative to exercise echocardiography .
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Participant_Condition
diagnosing myocardial ischemia .
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Participant_Age
Thirty-seven patients were entered into the study ( 35 arbutamine and exercise , 1 arbutamine only , 1 exercise only ) , of which 30 had angiographic evidence of coronary artery disease ( > or = 50 % lumen diameter narrowing ) .