934-27 Patterns of Target Lesion Calcification in Coronary Artery Disease

Intravascular ultrasound (IVUS) and coronary angiography were used to assess target lesion calcium (Ca) in 1155 native vessels in 1117 pts. IVUS detected lesion Ca in 841 (73%). The arc of Ca measured 115±110° and the length 3.5±3.7mm. Lesion Ca was only superficial in 48%, only deep in 28%, and both superficial and deep in 24%. The arc of superficial Ca measured 85±108° and the length 2.4±3.4 mm. 373 reference segments (32%) contained Ca; the arc measured 42±80° and the length 1.7±3.6 mm (all p<0.0001 vs lesion). Angiography detected Ca in only 440 lesions (38%, p<0.0001 vs IVUS), The angiographic detection of Ca was then compared to the arc, length, distribution (superficial vs deep), and location (lesion vs reference) of IVUS Ca. Using discriminant analysis, a model for predicting angiographic Ca included the arc of target lesion Ca, arc of superficial Ca, and length of reference Ca. It correctly predicted angiographic Ca in 74.4%.We ConcludeIVUS imaging shows that Ca is highly prevalent in most native vessel lesions (73%) and is usually superficial (70%). Angiography identifies only half of the calcified lesions; its sensitivity is influenced by the circumferential distribution and superficial location of lesion Ca and by the length of reference segment Ca. IVUS may be a necessary adjunctive imaging modality if device therapy strategies are determined by the presence, location, and distribution of Ca