Study of Coronary Artery Disease by Two Types of Angiography

Objective:

In patients with newly diagnosed cardiomyopathy it is the standard of care to perform coronary angiography. This procedure can separate ischemic from non-ischemic cardiomyopathy and identifies patients who may be eligible for revascularization as a therapeutic modality. With the advent of multidectector row-computed tomography technology, it is becoming possible to non-invasively identify significant atherosclerotic stenoses with acceptable sensitivity and specificity. The goal of this study is to compare non-invasive computed tomography (CT) angiography with traditional coronary angiography to identify proximal, and hence revascularizable, coronary artery disease in patients with cardiomyopathy. Revascularizable is defined a 3 vessel proximal disease, left main disease, or left main equivalent disease (ostial left anterior descending and ostial left circumflex).

Research Design:

This study is prospective, interventional, single site with the interpreting radiologists blinded to the results from previous angiography.

Methods:

Subjects will be patients with cardiomyopathy, defined as an ejection fraction less than 40%. Exclusion criteria include known allergy to contrast medium, previous anaphylaxis, and renal insufficiency (serum creatinine greater than 1.5). We would like to enroll 30 patients. After giving informed consent, all eligible patients will undergo CT angiography, performed using new multi-slice technology. The results of previously obtained transthoracic echocardiography and standard coronary angiography will be reviewed. Following CT angiography all patients will have a repeat measurement of serum creatinine to screen for contrast induced nephropathy. Results of the CT angiography will be analyzed to determine sensitivity and specificity for identifying revascularizable coronary artery disease, compared to coronary angiography as the gold standard.