The safety of intravenous dipyridamole thallium myocardial perfusion imaging. Intravenous Dipyridamole Thallium Imaging Study Group.

Abstract

Clinical data on 3,911 patients were collected from 64 individual investigators to evaluate the safety of intravenous dipyridamole-thallium imaging as an alternative to exercise thallium imaging for the evaluation of coronary artery disease. There were two deaths because of myocardial infarctions, two nonfatal myocardial infarctions, and six cases of acute bronchospasm. Chest pain occurred in 770 patients (19.7%). Headache and dizziness were reported by 476 patients (12.2%) and 460 patients (11.8%), respectively. ST-T changes on the electrocardiogram were seen in 292 patients (7.5%). Use of parenteral aminophylline to treat adverse events associated with intravenous dipyridamole brought complete relief of symptoms in 439 of 454 patients (96.7%). There Although information was collected on the diagnostic usefulness (i.e., sensitivity and specificity) of dipyridamole-thallium scintigraphy as part of this study, this information is not presented here. The interpretation of the sensitivity-specificity data is complex because the data were collected retrospectively; there was no uniform protocol, no standard test procedures or equipment, and no uniform experience in conducting the test for all investigators (e.g., some investigators provided data from only one patient, whereas others provided data from more than 100 patients).Additionally, demographic and baseline data were not collected on all patients who underwent intravenous dipyridamole-thallium imaging. Thus, estimation of mortality or morbidity rates for select subgroups of patients is not possible (e.g., the mortality rate in patients without a history of unstable angina).Despite these problems in design, however, this study presents data for the largest collection of patients, to date, who have undergone dipyridamolethallium scintigraphy, which allows evaluation of the safety of the procedure. Patient Characteristics and Intravenous Dipyridamole DosageOf the 3,911 patients in this study, 1,096 (28.0%) were patients who had intravenous dipyridamolethallium scintigraphy and coronary angiography performed within a 1-year period and whose tests were interpreted in a blinded fashion. Patient characteristics and dosage information were collected for all these 1,096 patients. Approximately two thirds of these 1,096 patients were male. The mean age of the patients was 57.7 years (SD, 10.4 years), with a range of 26-88 years. Almost 88% of the patients had a history of chest pain before undergoing thallium imaging. Nineteen patients (1.7%) had a history of nonanginal pain, 420 (38.3%) had stable angina, 505 (46.1%) had a history of unstable angina (i.e., chest pain at rest or recent acceleration of chest pain), and 16 (1.5%) had a history of nonspecific chest pain. Approximately 42% of the patients had a history of myocardial infarction, 9.0% had previous coronary artery bypass graft surgery, and 3.0% had a previous coronary angioplasty. The two most frequently reported concurrent diseases other than CAD were hypertension and cardiovascular disease, which were repo...

Surviving a stressful MIBI scan

“…In a study of 3,911 patients receiving dipyridamole intravenously during a stress test, 10 had serious adverse events: 4 had myocardial infarctions, two of which were fatal, and 6 had bronchospasm. 11 A study of dipyridamole in 10,541 echocardiograms on 9,122 patients found seven adverse events: one patient became asystolic secondary to an myocardial infarction, and two had episodes of asystole. 12 A retrospective review of patients undergoing dipyridamole stress testing found 19 adverse events, including one death, in 24,599 patients.…”

Advances in Pharmacologic Stress Agents: Focus on Regadenoson

“…Up to 80% of patients experience side effects resulting from the use of adenosine or dipyridamole for pharmacologic stress MPI (12)(13)(14)(15)(16). Most of these side effects are mild and include flushing, chest pain, dyspnea, dizziness, and nausea.…”

“…These frequent side effects, although not serious, are uncomfortable for the patient and create a need for increased monitoring time and care by the nuclear medicine staff. More serious events, including bronchospasm, atrioventricular block, and peripheral vasodilation (resulting in hypotension), are observed with lower frequency (7,12,(14)(15)(16). Patients with asthma and chronic obstructive pulmonary disease (COPD) are at increased risk of bronchoconstriction and respiratory problems resulting from the use of adenosine or dipyridamole (7,17,18).…”

“…Of particular interest are the less frequent but more serious adverse events, including bronchospasm (mediated by the A 1 , A 2B , and A 3 receptors), atrioventricular block (A 1 receptor), and peripheral vasodilation (A 2B receptor) resulting in hypotension (7,12,(14)(15)(16)(17)(18)(21)(22)(23)(24). More selective A 2A receptor agonists have the potential to mediate the desired level of hyperemia while reducing the frequency of adverse effects (21).…”

Vasodilator stress agents for myocardial perfusion imaging

“…On the other hand, 10 (0.26%) had major adverse events, 2 had fatal MI, 2 nonfatal MI, and 6 developed acute bronchospasm. 8 Despite the early understanding of the adenosinemediated vasodilatory effect of dipyridamole, there was initial reluctance toward the direct use of adenosine infusion for MPI, mainly due to concerns stemming from its known atrioventricular (AV) blocking properties. When Wilson et al demonstrated the safety of infusing relatively low doses of intravenous adenosine (35-140 lgÁkg -1 Áminute -1 ), 9 the superiority of this approach was quickly appreciated, especially with the much shorter half-life of adenosine as compared to dipyridamole.…”