Safety of different dosages of intravenous adenosine used in conjunction with diagnostic myocardial imaging techniques

Pharmacotherapy. Sep-Oct 1993;13(5):476-80.

Abstract

Study objective: To determine the safety of three different dosage regimens of intravenous adenosine.

Design: Open-label, observational safety evaluation.

Setting: University hospital-based department of nuclear medicine.

Patients: Cohort of 854 patients referred for myocardial perfusion imaging to evaluate their coronary artery disease and who were judged unable to perform physical exercise.

Interventions: Subjects underwent myocardial perfusion imaging in conjunction with one of three intravenous dosage regimens: 1 = fixed dosage 140 micrograms/kg/minute for 6 minutes; 2 = dosage titration to a maximum of 140 micrograms/kg/minute; and 3 = dosage titration to a maximum of 200 micrograms/kg/minute. In regimens 2 and 3, maximum tolerated dosages were continued for a minimum of 3 minutes prior to radioisotope injection.

Measurements and main results: Adenosine-induced hemodynamic, electrocardiographic, and biochemical changes were measured. Adverse effects of the different adenosine dosages were compared. Noncardiac side effects such as flushing, dyspnea, neck tightness, and lightheadedness occurred at a significantly higher rate during regimens 2 and 3 than regimen 1. Chest pain and first- and second-degree atrioventricular block were also more frequent during regimens 2 and 3. However, the frequency of other side effects such as complete heart block, hypotension, and ST segment depression did not differ among the regimens. High-dose adenosine was associated with a significant increase in serum uric acid, a significant decrease in blood glucose, and a significant increase in serum triglyceride levels. Mean changes in hemodynamics and electrocardiographic intervals were also not different among the groups except for a greater increase in PR interval in regimens 2 and 3 than regimen 1. Discontinuation of adenosine was infrequent (< 1%) and did not differ among the regimens.

Conclusions: Adenosine-assisted myocardial perfusion imaging procedures are relatively safe for evaluating coronary artery disease. Despite 82% of patients reporting at least one side effect, only 10 (< 1%) had to discontinue adenosine. No patient suffered any residual sequelae from the adverse effects. The fixed-dose regimen is associated with fewer subjective side effects and is better tolerated than titration regimens. Appropriate safety precautions should nonetheless be taken during adenosine infusions.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Adenosine / administration & dosage*
  • Adenosine / adverse effects
  • Adenosine / pharmacology
  • Adult
  • Aged
  • Aged, 80 and over
  • Blood Pressure / drug effects
  • Cohort Studies
  • Coronary Disease / diagnostic imaging*
  • Electrocardiography / drug effects
  • Female
  • Heart / diagnostic imaging*
  • Heart Rate / drug effects
  • Humans
  • Infusions, Intravenous
  • Male
  • Middle Aged
  • Organotechnetium Compounds
  • Oximes
  • Radionuclide Imaging
  • Technetium Tc 99m Sestamibi
  • Thallium Radioisotopes

Substances

  • Organotechnetium Compounds
  • Oximes
  • Thallium Radioisotopes
  • technetium Tc 94m teboroxime
  • Technetium Tc 99m Sestamibi
  • Adenosine