Panoramic coronary angiography

Department of Cardiology, E.O. Ospedali Galliera, Genoa, Italy. giortomm@tin.it

OBJECTIVES: We describe a new imaging technique for coronary angiography. BACKGROUND: The conventional approach to coronary angiography exploits static perspective imaging over multiple cardiac cycles, using a limited number of empirically selected views. This approach entails both lack and redundancy of information and may result in suboptimal visualization of the individual lesion, contributing to diagnostic inaccuracy. METHODS: We developed a new imaging technique exploiting dynamic perspective, obtained by transverse 180 degree rotation of the C arm of a conventional angiographic unit during standard selective coronary opacification and filming. This technique yields a picture of the coronary tree isocentrically rotating around the longitudinal axis and conveying complete three-dimensional information. RESULTS: A complete diagnostic run for both coronary arteries, including two 25 degree cranial and two 25 degree caudal scans is accomplished with a total cine time of 16 s and 45 ml of contrast medium, about half of that required by conventional angiography. In a series of 129 consecutive patients studied by both the conventional and the new technique with quantitative measurements of the severity of the stenoses, the final diagnosis was identical in 65. In no case was a stenosis detected only by the conventional approach. However, in 31 patients the new technique permitted identification of 34 critical stenoses (79+/-8% [mean +/- SD]) either underestimated (61+/-3% n = 24, p < 0.001) or undetected (21+/-22%, n = 10, p < 0.001) in the standard projections. In a further 28 cases, 33 subcritical lesions (60+/-5%) were visualized in the rotational images but were insignificant (24+/-22% p < 0.001) in the standard projections. In five additional patients, distinct laminar plaques were clearly visualized only by the panoramic approach. CONCLUSIONS: This new technique can be easily implemented on conventional angiographic equipment at no additional cost. It provides complete, operator-independent exploitation of the angiographic information, resulting in enhanced diagnostic accuracy.