Comparison of coronary artery lesion length by NIRS-IVUS versus angiography alone.

BACKGROUND: Intravascular ultrasound (IVUS) studies analyzing target lesion plaque burden (PB) have established that invasive coronary angiography commonly underestimates lesion length, predisposing to 'geographic miss' during a percutaneous coronary intervention, which has been associated with adverse outcomes. Plaque composition may also influence stent outcome. The present study used near-infrared spectroscopy and IVUS (NIRS-IVUS) to assess the prevalence of PB and lipid-core plaque (LCP) extending beyond angiographic borders of target lesions.

METHODS: Fifty-eight patients (58 lesions) undergoing NIRS-IVUS were identified. By invasive coronary angiography, target lesion length and minimum lumen diameter were measured. Plaque, defined as NIRS-IVUS atheroma (either PB>40% or LCP), was identified adjacent to the angiographic-defined lesion margins.

RESULTS: By NIRS-IVUS, atheroma (either PB>40% or LCP) was identified beyond angiographic lesion margins in 52/58 (90%) lesions. The mean lesion length was 13.4±5.9 mm by angiography and 19.8±7.0 mm (P<0.0001) by NIRS-IVUS. LCP extending beyond the angiographic border was observed in 30/58 (52%) lesions.

CONCLUSION: NIRS-IVUS imaging shows that target lesion length is commonly underestimated by angiography alone. This finding may have implications for stent length selection and avoidance of geographic miss.