Clinical Outcomes and Patient Perceived Symptoms With Iso-Osmolar and Low Osmolar Contrast Used During Lower Extremity Peripheral Artery Intervention.

Real-world data comparing iso-osmolar contrast media (IOCM) and low-osmolar contrast media (LOCM) during lower extremity (LE) peripheral artery interventions (PAI), particularly with respect to patient-reported symptoms during procedures and clinical outcomes, remain limited. A total of 440 patients undergoing LE PAI with either IOCM (Iodixanol) or LOCM (Iohexol) were retrospectively analyzed from the multicenter core laboratory adjudicated Excellence in peripheral artery disease (XLPAD) Registry (NCT01904851; 2020 to 2023). In addition, a prospective cohort of 60 patients was enrolled to assess intraprocedural symptoms using a 0 to 10 scale for pain, heaviness, tingling, and burning sensations. The primary endpoint was the 1-year incidence of major adverse limb events (MALE), a composite of all-cause mortality, repeat revascularization, major amputation, myocardial infarction, or stroke. Secondary outcomes included 30-day periprocedural complications, patient-reported symptoms, and the need for repeated digital subtraction angiograms (DSA) due to limb movement. An exploratory analysis including 40 additional retrospectively enrolled patients to the prospective cohort further evaluated DSA repetition rates. Finally, a mixed-effects logistic regression with institution as random effect and patient factors as fixed effect was used to access factors affecting choice of IOCM vs LOCM. Of the 440 patients, 244 (55.5%) received IOCM and 196 (45.5%) LOCM. The mean age was 67.8 ± 10.4 years. IOCM was more frequently used in patients with advanced limb-threatening ischemia (45.1% vs 36.7%, p = 0.077), severe calcification (19.3% vs 10.2%, p = 0.009), and diffuse arterial disease (41.0% vs 9.2%, p <0.001). Technical (95.5% vs 96.9%, p = 0.4) and procedural success (92.6% vs 95.8%, p = 0.2), as well as periprocedural complication rates (4.5% vs 3.6%, p = 0.3), were similar between groups. One-year MALE rates did not differ significantly (p = 0.5). In the prospective cohort, nearly half of patients reported intraprocedural discomfort, with no significant differences in frequency (57.9% vs 46.3%, p = 0.4) or severity (mean pain score: 1.9 ± 2.3vs. 1.8 ± 2.7, p = 0.6) between contrast groups. The need for repeated DSA due to limb motion was numerically lower in the IOCM group (26.3% vs 29.3%, p = 0.076). Patients receiving IOCM experienced significantly shorter postprocedural hospital stays (0 [0, 1.00] vs 1.00 [0, 3.00]; p = 0.001). Institutional preference outweighed other predictors for selecting IOCM over LOCM (variance 13.42, standard deviation 3.663). In real-world practice, IOCM is preferentially used in patients undergoing more complex PAI compared with LOCM, with no difference in 1-year MALE. Institutional practice was the predominant driver for IOCM use. Patient-reported procedural symptoms and the need for repeated DSA were commonly observed and warrant further investigation.