Comparison of the effects of contrast medium and low-molecular-weight dextran on coronary optical coherence tomographic imaging in relatively complex coronary lesions.

Background: Optical coherence tomography (OCT) has gained increasing popularity in coronary artery intervention due to its high resolution and excellent tissue correlation as a novel intravascular imaging modality. However, the current use of OCT requires contrast agent injection for imaging, and excessive use of contrast agents may adversely affect renal function, exacerbate cardiac burden, and even lead to contrast agent-induced nephropathy and heart failure. In recent years, several researchers have proposed the use of low molecular weight dextran (LMWD) as a substitute for contrast agents in OCT imaging because of its low toxicity, low cost, and wide availability. However, the inclusion of lesions in these studies is relatively simple, and the image quality criteria remain to be optimized. Methods: This study included 26 patients with coronary artery disease who were scheduled for OCT imaging in a real-world clinical practice involving various complex lesions. All patients underwent two OCT examinations at the same vascular site, one each using contrast agent and LMWD. Both contrast media and LMWDs were infused by an autoinjector. The primary endpoint of the study was the average image quality score. Secondary endpoints included clear image length, clear image segments, minimum lumen area, average lumen area, and contrast-induced nephropathy, among others. Results: In terms of image clarity, the average image quality score was similar when comparing contrast media with LMWD (3.912 ± 0.175 vs. 3.769 ± 0.392, P = 0.071). The lengths of the clear images and the segments of the clear images were also similar between the two groups (50.97 ± 16.25 mm vs. 49.12 ± 18.15 mm, P = 0.110; 255.5 ± 81.29 vs. 250.5 ± 89.83, P = 0.095). Additionally, strong correlations were noted between the two flushing solutions regarding the minimum lumen area and mean lumen area. During their hospital stay, none of the patient exhibited deterioration in renal function, and no patient experienced any major adverse cardiovascular events. Conclusions: The quality of coronary artery OCT imaging using LMWD may be comparable to that achieved with traditional contrast agents, even in real-world clinical practice involving various complex lesions. For high-risk patients, LMWD may serve as an excellent substitute for contrast agents in OCT examinations.