Quality of stress tests performed for myocardial perfusion scintigraphy

Overview

Introduction:
Appropriate performance of stress test is crucial for a quality of reports of a stress myocardial perfusion scintigraphy.

Purpose:
Retrospective analysis of stress tests quality performed in our department in the years 2007-2009.

Methods:
Stress test could be performed in different forms. Physical stress is the most physiological. Pharmacological (in the Czech dipyridamole or dobutamine) or combined stress could be used when physical stress is inappropriate. Unless no angina occurs, physical stress is considered adequate if the patient achieves more than 85 % of maximal age-predicted heart rate (MPHR) or double-product above 25 000.

Results:
We analyzed 1189 patients (629 females, 560 males), average age of 62,5 (24-88) y referred for stress myocardial perfusion imaging. We used following types of stress: physical only in 687 (58 %), dipyridamole in 73 (6 %), dipyridamole with physical stress in 418 (35 %), and dobutamine in 10 (1 %) patients. Required heart rate was achieved in 626 (91 %) patients stressed with physical activity. Patients who did not achieve required heart rate fulfilled adequate double-product in 41 cases, angina occurred in 8 patients, 8 patients achieved 75 % of MPHR (myocardial infarction in the history) and others were symptom limited (and simultaneously contraindicated to pharmacological stress).

Conclusion:
Absolute majority of our patients were stressed adequately, so we do not produce false negative reports.

Key words:
stress test, myocardial perfusion scintigraphy, physical stress, heart rate