Low-molecular-weight dextran for optical coherence tomography may not be protective against kidney injury in patients with renal insufficiency.

Background: Low-molecular-weight dextran (LMWD) is considered a safe alternative to contrast media for blood displacement during optical coherence tomography (OCT) imaging.

Aim: To investigate whether the use of LMWD for OCT is protective against kidney injury in patients with advanced renal insufficiency.

Methods: In this retrospective cohort study, we identified 421 patients with advanced renal insufficiency (estimated glomerular filtration rate < 45 mL/min/1.73 m²) who underwent coronary angiography or percutaneous coronary intervention; 79 patients who used additional LMWD for OCT imaging (LMWD group) and 342 patients who used contrast medium exclusively (control group). We evaluated the differences between these two groups and performed a propensity score-matched subgroup comparison.

Results: The median total volume of contrast medium was 133.0 mL in the control group vs 140.0 mL in the LMWD group. Although baseline renal function was not statistically different between these two groups, the LMWD group demonstrated a strong trend toward the progression of renal insufficiency as indicated by the greater change in serum creatinine level during the 1-year follow-up compared with the control group. Patients in the LMWD group experienced worsening renal function more frequently than patients in the control group. Propensity score matching adjusted for total contrast media volume consistently indicated a trend toward worsening renal function in the LMWD group at the 1-year follow-up. Delta serum creatinine at 1-year follow-up was significantly greater in the LMWD group than that in the control group [0.06 (-0.06, 0.29) vs -0.04 (-0.23, 0.08) mg/dL, P = 0.001], despite using similar contrast volume.

Conclusion: OCT using LMWD may not be protective against worsening renal function in patients with advanced renal insufficiency.