A Paired-Comparision of the MultiFunction CardioGramsm (MCG) and Sestamibi SPECT Myocardial Perfusion Imaging (MPI) to Quantitative Coronary Angiography for the Detection of Relevant Coronary Artery Obstruction (≥70%) - A Single-Center Study of 116 Consecutive Patients Referred for Coronary Angiography

<p><b>Background:</b> An analysis of the US National Cardiovascular Data Registry has revealed that only 38% of patients referred for coronary angiography after non-invasive coronary testing have relevant coronary obstruction (CO) (&#8805;70%) of one or more coronary arteries.</p><p><b>Methods:</b> A single-center trial was undertaken in 165 consecutive, symptomatic patients with either known or suspected coronary disease and/or valve disease(VHD) who agreed to undergo cardiac catheterization and coronary angiography if stress myocardial perfusion imaging was abnormal. A total of 116 patients with abnormal SPECT MPI tests, persistent chest pain, or significant VHD underwent final analysis. An MCG coronary obstruction (CO) score of &#8805; 4.0 was considered indicative of relevant CO (&#8805;70%) in one or more coronary arteries. Angiographic results were finalized by consensus of two angiographers.</p><p><b>Results:</b> CO (&#8805;70%) was present in 53 of 116 patients (46%). The MCG CO score was significantly higher for patients with relevant CO (5.4 &#177; 1.9 vs. 2.5 &#177; 1.9). The MCG correctly classified 103 of the 116 patients (89%) enrolled in the study as either having or not having CO (&#8805;70%) (sensitivity- 91%; specificity- 87%; NPV- 92%; PPV- 86%). SPECT MPI was abnormal in 99 of the 116 (85%) patients undergoing catheterization, but correctly classified only 54 of the 116 patients (47%) entered in the study as either having or not having relevant CO (sensitivity-85%; specificity-14%; NPV - 53%; PPV- 45%).</p><p><b>Conclusions:</b> The MCG was shown in this paired-comparison trial with SPECT MPI to safely and accurately identify patients with relevant CO (&#8805;70%) prior to catheterization.</p