Abstract
BACKGROUND: Ischemic preconditioning is characterized by the limitation of infarct size or ischemic signs after one or more brief episodes of ischemia, a process that probably involves stimulation of adenosine receptors. One human model of ischemic preconditioning is repetitive occlusion of a coronary artery during angioplasty. By using this method of inducing ischemia, we tested the hypothesis that blockade of adenosine receptors with aminophylline would abolish ischemic preconditioning in human beings. METHODS: Twenty-six patients undergoing angioplasty were randomly assigned to receive either aminophylline (6 mg/kg IV) or placebo before repetitive coronary occlusion (two 2-minute occlusions separated by 5 minutes). ST-segment changes on the surface electrocardiogram were used as a measure of myocardial ischemia. Serum theophylline levels and the conduction response to an intravenous bolus of adenosine were used to assess the efficacy of adenosine receptor blockade. RESULTS: Repetitive coronary occlusion resulted in a reduction in ST-segment shift in 9 of 13 patients given placebo. In contrast, 9 of 13 patients receiving aminophylline had an increase in ST-segment shift on the second occlusion (P =.002). Patients receiving aminophylline (mean serum theophylline level of 8.38 +/- 0.45 mg/dL) did not have significant conduction block with intravenous adenosine. CONCLUSIONS: Repetitive coronary occlusion reduces the signs of ischemia in human beings, a process limited by blockade of adenosine receptors.
| Original language | English (US) |
|---|---|
| Journal | American Heart Journal |
| Volume | 142 |
| Issue number | 3 |
| State | Published - Sep 2001 |
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ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
Cite this
Blockade of adenosine receptors with aminophylline limits ischemic preconditioning in human beings. / Schaefer, Saul; Correa, S. D.; Valente, R. J.; Laslett, L. J.
In: American Heart Journal, Vol. 142, No. 3, 09.2001.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Blockade of adenosine receptors with aminophylline limits ischemic preconditioning in human beings.
AU - Schaefer, Saul
AU - Correa, S. D.
AU - Valente, R. J.
AU - Laslett, L. J.
PY - 2001/9
Y1 - 2001/9
N2 - BACKGROUND: Ischemic preconditioning is characterized by the limitation of infarct size or ischemic signs after one or more brief episodes of ischemia, a process that probably involves stimulation of adenosine receptors. One human model of ischemic preconditioning is repetitive occlusion of a coronary artery during angioplasty. By using this method of inducing ischemia, we tested the hypothesis that blockade of adenosine receptors with aminophylline would abolish ischemic preconditioning in human beings. METHODS: Twenty-six patients undergoing angioplasty were randomly assigned to receive either aminophylline (6 mg/kg IV) or placebo before repetitive coronary occlusion (two 2-minute occlusions separated by 5 minutes). ST-segment changes on the surface electrocardiogram were used as a measure of myocardial ischemia. Serum theophylline levels and the conduction response to an intravenous bolus of adenosine were used to assess the efficacy of adenosine receptor blockade. RESULTS: Repetitive coronary occlusion resulted in a reduction in ST-segment shift in 9 of 13 patients given placebo. In contrast, 9 of 13 patients receiving aminophylline had an increase in ST-segment shift on the second occlusion (P =.002). Patients receiving aminophylline (mean serum theophylline level of 8.38 +/- 0.45 mg/dL) did not have significant conduction block with intravenous adenosine. CONCLUSIONS: Repetitive coronary occlusion reduces the signs of ischemia in human beings, a process limited by blockade of adenosine receptors.
AB - BACKGROUND: Ischemic preconditioning is characterized by the limitation of infarct size or ischemic signs after one or more brief episodes of ischemia, a process that probably involves stimulation of adenosine receptors. One human model of ischemic preconditioning is repetitive occlusion of a coronary artery during angioplasty. By using this method of inducing ischemia, we tested the hypothesis that blockade of adenosine receptors with aminophylline would abolish ischemic preconditioning in human beings. METHODS: Twenty-six patients undergoing angioplasty were randomly assigned to receive either aminophylline (6 mg/kg IV) or placebo before repetitive coronary occlusion (two 2-minute occlusions separated by 5 minutes). ST-segment changes on the surface electrocardiogram were used as a measure of myocardial ischemia. Serum theophylline levels and the conduction response to an intravenous bolus of adenosine were used to assess the efficacy of adenosine receptor blockade. RESULTS: Repetitive coronary occlusion resulted in a reduction in ST-segment shift in 9 of 13 patients given placebo. In contrast, 9 of 13 patients receiving aminophylline had an increase in ST-segment shift on the second occlusion (P =.002). Patients receiving aminophylline (mean serum theophylline level of 8.38 +/- 0.45 mg/dL) did not have significant conduction block with intravenous adenosine. CONCLUSIONS: Repetitive coronary occlusion reduces the signs of ischemia in human beings, a process limited by blockade of adenosine receptors.
UR - http://www.scopus.com/inward/record.url?scp=18144438201&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=18144438201&partnerID=8YFLogxK
M3 - Article
C2 - 11526374
AN - SCOPUS:18144438201
VL - 142
JO - American Heart Journal
JF - American Heart Journal
SN - 0002-8703
IS - 3
ER -