Both Exercise and Adenosine Stress Testing

The purpose of this study is to compare the 2-year cardiac outcomes for women with limited exercise capability based on the resuls of either pharmacological stress myocardial perfusion imaging or a combined protocol that incorporates both exercise and pharmacological stress. The goal of the study is to compare these two methods for patient tolerability, safety and prognostic value

Coronary artery disease remains the leading cause of morbidity and mortality in women accounting for more than 250,000 deaths per year. Despite the high prevalence in ischemic heart disease in women, most clinical trials have focused on male cohorts. The optimal non-invasive test for evaluation of ischemic heart disease in women is unknown. A number of different modalities have been employed including exercise ECG stress testing, 2-dimensional stress echocardiography, SPECT myocardial perfusion imaging, and electron beam computerized tomography.

The cohort of women for whom to perform testing upon is also ill-defined. Myocardial perfusion imaging, in conjunction with pharmacologic stress testing, has also been shown to be effective in the diagnosis of women with known or suspected coronary artery disease as well as in for risk stratification. Recently, pharmacologic stress has been combined with low-level exercise, enhancing test tolerability and SPECT perfusion image quality. Furthermore, the use of a combined adenosine and exercise protocol may detect greater amounts of ischemia with perfusion imaging that with an exercise test alone. Therefore, in women who may be unable to perform maximal exercise, this combined pharmacologic and exercise imaging protocol may possess a significant advantage over adenosine stress testing alone.

The aim of this study is to compare safety and symptoms associated with these two methods of stress testing. The current study also seeks to establish the optimal method for detection of coronary artery disease in women who have a limited capacity for exercise (DASI score ≤5 METS), also well as examine the prognostic value of each method of testing by comparing the two-year event rates for women who undergo adenosine SPECT imaging or SPECT imaging using adenosine with adjunctive exercise.

Eligibility Criteria:
Inclusion Criteria:

* Female
* Age greater to or equal to 60 years old
* Must present with chest pain, fatigue, or other anginal equivalent symptoms
* Must be referred for stress testing based on clinical indications
* Must be able to provide written informed consent

Exclusion Criteria:

* Women with known coronary artery disease (\>50% lesion OR prior MI OR prior revascularization)
* Inability to perform any exercise on a treadmill
* Nuclear medicine study within the preceding 30 days
* Contraindication to adenosine, including moderate to severe COPD or asthma, second or third degree AV block, or known hypersensitivity to adenosine or aminophylline
* Left bundle branch block or electronic ventricular pacemaker
* Significant valvular heart disease
* Hemodynamic instability (blood pressure \>210/110 ml/Hg or \<90/60 mm/Hg)
* 2° or 3° atrioventricular block
* Symptomatic heart failure
* Ingestion of theophylline or dipyridamole within the preceding 48 hours
* Unavailability for follow-up