Limitations of angiography in the detection of target lesion calcium. No significant differences today compared to 1995

Abstract

In 1995, my colleagues and I at the Washington Hospital Center (Washington, DC, United States) published an intravascular ultrasound (IVUS) vs angiographic assessment of calcium in 1155 lesions targeted for percutaneous coronary intervention (figure 1)1. Angiography detected calcium in 440 lesions (38%), but IVUS detected lesion calcium in 841 lesions (73%). Among these 1155 lesions, 27% had no IVUS calcium, 26% had 1-quadrant IVUS calcium, 21% had 2 quadrants, 15% had 3 quadrants, and 11% had 4-quadrant IVUS calcium. When present, target lesion calcium was only superficial in 48%, only deep in 28%, and both superficial and deep in 24%. Therefore, some superficial calcium was present in 72% of the 841 calcium-containing lesions (1-quadrant superficial calcium in 35%, 2 quadrants in 31%, 3 quadrants in 18%, and 4-quadrant superficial calcium in 18%). The diagnostic ability of angiography to detect calcium was primarily dependent on the arc and length of calcium, but also on whether calcium was or not superficial (figure 1). However, there was also a curious 10% rate of angiographic false positives attributed to the difficulty differentiating perivascular or reference segment calcium from intralesional calcium. However, it was never clear whether there was a systematic problem with angiographic calcium...