Safety and feasibility of atropine added in patients with sub-maximal heart rate during exercise myocardial perfusion SPECT.

Background: Failure to reach 80% of maximal predicted heart rate (HR) during exercise may render a myocardial perfusion single photon emission computed tomography (SPECT) study non-diagnostic for ischemia detection. We sought to investigate the injection of atropine in patients who fail to achieve 80% of age-predicted HR during exercise performed for myocardial perfusion SPECT (MPS), defining its safety and efficacy to raise HR to adequate levels as well as its effect on MPS interpretation.

Methods And Results: Between January 2002 and December 2004, we studied 3,150 consecutive patients (2,253 men and 897 women, mean age 55 +/- 6 years) who were referred to a single office-based nuclear cardiology laboratory for MPS using SPECT imaging.

Relationship between exercise-induced ST segmental depression and myocardial ischemia assessed by technetium-99m tetrofosmin SPECT imaging in patients with inferior Q wave myocardial infarction.

Background: ST segment depression (STD) is a standard electrocardiographic sign of myocardial ischemia. Although STD may represent reciprocal changes in patients with previous myocardial infarction, studies of reciprocal changes during exercise testing are scarce.

Methods: From December 1999 to December 2000, 160 patients (119 males, 41 females, mean age 54 +/- 8 years), undergoing, maximal or symptom-limited exercise treadmill test (Bruce-protocol), myocardial perfusion scintigraphy using technetium-99m tetrofosmin single photon emission computed tomography (SPECT) imaging, within 30 days of an uncomplicated inferior Q wave myocardial infarction.