Intravascular thermographic assessment in human coronary atherosclerotic plaques by a novel flow-occluding sensing catheter: a safety and feasibility study.

OBJECTIVE: To report the safety and feasibility of a new occluding thermographic catheter in patients with coronary artery disease. BACKGROUND: Although plaque temperature heterogeneity is shown in atheromatous plaques, significant underestimation is encountered due to the cooling effect of the uninterrupted blood flow. METHODS: The catheter was positioned at the stenotic site. Blood flow was interrupted by an expandable braid located at the distal portion of the catheter. Then, thermographic assessment was performed. RESULTS: In one patient, the catheter could not reach the lesion due to tortuosity. Of the 20 lesions evaluated, 5 were excluded due to unsuccessful interruption of blood flow. We identified 5 lesions with a 0.3 degrees Celcius elevations compared to the same site without interruption of blood flow. There were no procedural complications. CONCLUSION: The new catheter-occluding thermographic device, while avoiding the blood flow cooling effect, appears to be safe and feasible for the assessment of human plaque temperature heterogeneity.

Lesion length assessment using a new vessel caliper.

Assessment of coronary lesion length using visual estimation or quantitative coronary angiography can be unreliable. We tested the accuracy of a new handheld caliper device to measure lesion length in a bench-top model and in eight patients undergoing percutaneous coronary intervention (PCI). Caliper-derived length measurements were compared to the known reference distance in the bench-top model and visual or intravascular ultrasound (IVUS)-derived measurements in vivo. In the coronary model, caliper-derived measurements were accurate and correlated well with known reference distances regardless of the angiographic projection. During PCI, there was a poor correlation between the best visual estimate of length and IVUS-derived measurements. In contrast, caliper-derived measurements correlated closely with IVUS-derived measurements. This handheld caliper provides a simple and accurate method of assessing intracoronary lesion length and may be particularly useful during coronary stenting and when adjunctive brachytherapy is performed.