Dear editor
We thank Dr. Gozde Celik for their thoughtful letter regarding our published study, “Lumbar Sympathetic Radiofrequency Ablation for Peripheral Arterial Disease: A Short-Term, Self-Controlled, Retrospective Pilot Study of 16 Patients”. We appreciate the opportunity to provide the following clarifications.
Patient Selection and Revascularization Status
All 16 patients were evaluated by a multidisciplinary vascular team prior to enrollment. The specific reasons for offering lumbar sympathetic radiofrequency ablation (LSRA) rather than revascularization are summarized in the Table 1 below:
Table 1.
Reasons for Selecting LSRA in the 16 Enrolled Patients
| Reason for LSRA | n (%) |
|---|---|
| Anatomically unsuitable for revascularization | 8 (50.0%) |
| Advanced age with prohibitive cardiopulmonary risk for endovascular/surgical intervention | 3 (18.8%) |
| Recurrent symptoms after multiple prior revascularization procedures | 4 (25.0%) |
| Thromboangiitis obliterans (TAO) | 1 (6.2%) |
Among the 4 patients with recurrent symptoms after multiple prior revascularization procedures, 3 had lower extremity atherosclerotic occlusive disease (ASO) and 1 had TAO. Given that these patients had experienced symptom recurrence following repeated endovascular revascularization, LSRA was directly selected as the treatment approach. Encouraged by the favorable postoperative outcome observed in the first TAO patient, the second TAO patient was likewise directly treated with LSRA. Following LSRA, both TAO patients showed immediate improvement in lower-extremity skin temperature and pain relief without undergoing endovascular intervention.
Attribution of Day-7 Physiological Changes to LSRA
We provide two clarifications regarding the postoperative physiological assessments:
First, all patients received standardized background pharmacotherapy from the time of hospital admission, prior to the procedure. This regimen included: (1) aspirin (100 mg once daily) for antiplatelet therapy; (2) atorvastatin (20 mg once daily) or rosuvastatin (10 mg once daily) for lipid management and plaque stabilization; and (3) alprostadil (10 ug intravenous infusion once daily) for peripheral vasodilation and microcirculation improvement. These medications were part of the standard conservative management protocol and were continued throughout the perioperative period without modification. The postoperative changes observed at day 7 therefore represent changes above and beyond the established baseline medication effect.
Second, in clinical practice, patients showed noticeable improvement in lower-extremity skin temperature immediately following the radiofrequency ablation (within hours of the procedure). However, the purpose of our study was not to document the acute physiological response to LSRA, but rather to evaluate the durability of microcirculation improvement and the sustained analgesic effect at a clinically meaningful time point. The day-7 assessment was therefore deliberately chosen to capture the persistence of benefit beyond the immediate post-ablation period, during which transient procedural factors (local anesthesia, immediate thermal effects) might confound interpretation. We agree that future studies would benefit from serial measurements (eg, immediately post-procedure, day 1, day 3, day 7) to characterize the time course of physiological changes.
Clinical Meaningfulness of Effect Sizes
We fully agree with Dr. Celik that large standardized effect sizes do not inherently establish clinical importance-particularly for surrogate physiological endpoints such as toe skin temperature and perfusion index. As stated in our manuscript, this study represents a preliminary, hypothesis-generating pilot investigation. The study was designed to assess whether LSRA is associated with short-term physiological changes, not to establish clinical efficacy. Accordingly, we interpret the large effect sizes observed in our study as evidence of a statistically robust short-term physiological response following LSRA, rather than as proof of clinical efficacy. Whether these physiological changes translate into clinically relevant benefit-defined by endpoints such as wound healing, limb salvage, amputation-free survival, and quality of life-remains to be established in future prospective, controlled studies with extended follow-up.
Disclosure
The authors declare no conflicts of interest in this communication.