Photobiomodulation in Coronary Artery Bypass Grafting With No-Touch vs Conventional Saphenous Vein Harvesting. (PHOTON)

Impact of Photobiomodulation in Coronary Artery Bypass Surgery: Comparison Between No-Touch and Conventional Saphenous Vein Harvesting Techniques on Clinical Outcomes, Functional Capacity, and Wound Healing: A Randomized Clinical Trial

This randomized, double-blind clinical trial aims to evaluate the impact of photobiomodulation therapy on postoperative outcomes in patients undergoing coronary artery bypass grafting (CABG). The study will compare two techniques for saphenous vein graft harvesting: the conventional technique and the no-touch technique. Participants will be randomly allocated into four groups: conventional harvesting with placebo, conventional harvesting with photobiomodulation, no-touch harvesting with placebo, and no-touch harvesting with photobiomodulation. The primary objective is to evaluate the effects of photobiomodulation on wound healing and postoperative complications related to the saphenous vein harvesting site. Secondary outcomes include clinical outcomes and functional capacity after surgery. The results may contribute to improving postoperative recovery and optimizing surgical strategies in patients undergoing myocardial revascularization.

Study Overview

• Status: Not yet recruiting
• Conditions: Coronary Artery Disease; Surgical Wound Healing; Coronary Artery Bypass Graft (CABG)
• Intervention / Treatment: Device: Placebo Laser; Procedure: Conventional Saphenous Vein Harvesting; Device: Photobiomodulation Therapy; Procedure: No-Touch Saphenous Vein Harvesting

Detailed Description

Cardiovascular diseases remain one of the leading causes of morbidity and mortality worldwide. Coronary artery bypass grafting (CABG) is a widely performed surgical procedure for the treatment of advanced coronary artery disease. The saphenous vein is frequently used as a graft in CABG; however, complications related to vein harvesting, including wound infection, delayed healing, and postoperative pain, remain relevant clinical concerns.

The no-touch technique for saphenous vein harvesting has been proposed as a strategy to preserve the structural integrity of the vein and potentially improve graft patency and reduce local tissue trauma. In addition, photobiomodulation therapy (low-level laser therapy) has demonstrated beneficial effects on tissue repair, inflammation modulation, and wound healing.

This study, named PHOTON Study, is a randomized, double-blind, controlled clinical trial designed to investigate the effects of photobiomodulation therapy in patients undergoing CABG. Participants will be randomized into four groups according to the harvesting technique and the use of photobiomodulation therapy. This study protocol was developed in accordance with the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) guidelines.

Photobiomodulation will be applied using a cluster laser device (E-light, DMC Equipamentos Ltda., Brazil) with a wavelength of 660 nm and output power of 100 mW. The laser will be applied locally along the surgical incision of the saphenous vein harvesting site using a point technique with standardized spacing between application points. The intervention will be performed intraoperatively and during the early postoperative period.

The primary outcomes include wound healing and postoperative complications related to the saphenous vein harvesting site. Secondary outcomes include clinical outcomes and functional capacity following surgery.

This trial may contribute to improving postoperative care and recovery in patients undergoing coronary artery bypass grafting.

• Study Type: Interventional
• Enrollment (Estimated): 292
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Solange Guizilini, PhD; Phone Number: +55 11 982887753; Email: sguizilini@unifesp.br

Study Locations

• Brazil
  • São Paulo
    • São Paulo, São Paulo, Brazil, 04021001
      • Hospital São Paulo, Federal University of São Paulo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients diagnosed with coronary artery disease scheduled to undergo elective coronary artery bypass grafting (CABG)
• Use of the saphenous vein as a graft for myocardial revascularization
• Ability to understand the study procedures and provide written informed consent

Exclusion Criteria:

• Emergency coronary artery bypass surgery
• Previous surgery in the lower limb that prevents saphenous vein harvesting
• Active infection at the surgical site or lower limb
• Severe peripheral arterial disease in the lower limbs
• Hemodynamic instability preventing study protocol procedures
• Participation in another interventional clinical trial that may interfere with the outcomes of this study
• Patients unable to perform postoperative functional capacity assessments
• Individuals with highly pigmented skin or sensibility that may alter light absorption and penetration of the photobiomodulation therapy.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Conventional Harvesting + Placebo; Patients undergoing conventional saphenous vein harvesting with simulated laser application (placebo).	Device: Placebo Laser; Simulated photobiomodulation therapy applied using the same laser device without emission of therapeutic laser energy. This placebo procedure is used to maintain blinding of participants and outcome assessors.; Procedure: Conventional Saphenous Vein Harvesting; Conventional Saphenous Vein Harvesting refers to the traditional open surgical technique used to obtain the great saphenous vein for grafting procedures, most commonly in coronary artery bypass grafting (CABG). The procedure involves a continuous longitudinal incision along the course of the vein in the lower limb, allowing direct visualization and careful dissection of the vessel from surrounding tissues. Side branches are ligated or clipped, and the harvested vein is subsequently prepared for use as a vascular graft. The technique is performed under sterile surgical conditions by qualified surgeons.
Experimental: Conventional Harvesting + Photobiomodulation; Patients undergoing conventional saphenous vein harvesting with active photobiomodulation therapy applied to the surgical incision.	Procedure: Conventional Saphenous Vein Harvesting; Conventional Saphenous Vein Harvesting refers to the traditional open surgical technique used to obtain the great saphenous vein for grafting procedures, most commonly in coronary artery bypass grafting (CABG). The procedure involves a continuous longitudinal incision along the course of the vein in the lower limb, allowing direct visualization and careful dissection of the vessel from surrounding tissues. Side branches are ligated or clipped, and the harvested vein is subsequently prepared for use as a vascular graft. The technique is performed under sterile surgical conditions by qualified surgeons.; Device: Photobiomodulation Therapy; Photobiomodulation will be applied using a cluster laser device (E-light, DMC Equipamentos Ltda., Brazil) with wavelength of 660 nm and output power of 100 mW. The therapy will be applied along the surgical incision of the saphenous vein harvesting site using a point technique with standardized spacing between application points. The intervention will be performed intraoperatively and during the early postoperative period.
Placebo Comparator: No-touch Harvesting + Placebo; Patients undergoing saphenous vein harvesting using the no-touch technique with simulated laser application.	Device: Placebo Laser; Simulated photobiomodulation therapy applied using the same laser device without emission of therapeutic laser energy. This placebo procedure is used to maintain blinding of participants and outcome assessors.; Procedure: No-Touch Saphenous Vein Harvesting; No-Touch Saphenous Vein Harvesting refers to a surgical technique for harvesting the great saphenous vein in which the vein is removed together with a pedicle of surrounding perivascular tissue, avoiding direct manual manipulation and excessive distension of the vessel. The procedure is performed through an open incision under sterile conditions, preserving the vein's adventitia, vasa vasorum, and surrounding connective tissue in order to minimize endothelial injury and maintain vascular integrity. Side branches are carefully ligated or clipped, and the harvested graft is prepared according to institutional surgical protocols for subsequent use in vascular or coronary artery bypass procedures.
Experimental: No-touch Harvesting + Photobiomodulation; Patients undergoing saphenous vein harvesting using the no-touch technique with active photobiomodulation therapy applied to the surgical incision.	Device: Photobiomodulation Therapy; Photobiomodulation will be applied using a cluster laser device (E-light, DMC Equipamentos Ltda., Brazil) with wavelength of 660 nm and output power of 100 mW. The therapy will be applied along the surgical incision of the saphenous vein harvesting site using a point technique with standardized spacing between application points. The intervention will be performed intraoperatively and during the early postoperative period.; Procedure: No-Touch Saphenous Vein Harvesting; No-Touch Saphenous Vein Harvesting refers to a surgical technique for harvesting the great saphenous vein in which the vein is removed together with a pedicle of surrounding perivascular tissue, avoiding direct manual manipulation and excessive distension of the vessel. The procedure is performed through an open incision under sterile conditions, preserving the vein's adventitia, vasa vasorum, and surrounding connective tissue in order to minimize endothelial injury and maintain vascular integrity. Side branches are carefully ligated or clipped, and the harvested graft is prepared according to institutional surgical protocols for subsequent use in vascular or coronary artery bypass procedures.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of surgical wound complications at the saphenous vein harvesting site	Occurance of wound infection at the surgical incision of the saphenous vein harvesting site.	From postoperative hospitalization to 30 days and 3 months after surgery.
Functional capacity assessed by the Six-Minute Walk Test	Functional capacity will be evaluated using Six-Minute Walk Test to assess exercise tolerance and postoperative recovery in patients undergoing coronary artery bypass grafting.	From preoperatory assessment to postoperative day 5 or at hospital discharge, 30 days and 3 months follow-up.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency and severity of adverse responses to photobiomodulation therapy	Assessment of the frequency and severity of adverse reactions associated with photobiomodulation therapy during the hospital stay.	From the first photobiomodulation therapy session until hospital discharge (Postoperative day 5 or earlier, if discharged).
All-cause mortality	Incidence of death from any cause following coronary artery bypass grafting.	Hospital discharge, 30 days after discharge and 3 months after discharge
Hospital readmission	Incidence of hospital readmission following coronary artery bypass grafting.	30 days and 3 months after discharge
Myocardial infarction	Incidence of myocardial infarction following coronary artery bypass grafting.	Perioperative, 30 days after discharge and 3 months after discharge.
Length of stay in the intensive care unit (ICU)	Duration of stay in the intensive care unit measured in days after surgery.	From date of surgery until ICU discharge (assessed up to 30 days).
Length of hospital stay	Total duration of hospital stay measured in days.	From hospital admission until hospital discharge (assessed up to 60 days)
Plasma interleukin-1 (IL-1) levels	Assessment of plasma IL-1 concentrations measured by enzyme-linked immunosorbent assay (ELISA).	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Plasma interleukin-6 (IL-6) levels	Assessment of plasma IL-6 concentrations measured by enzyme-linked immunosorbent assay (ELISA).	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Plasma interleukin-8 (IL-8) levels	Assessment of plasma IL-8 concentrations measured by enzyme-linked immunosorbent assay (ELISA).	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Plasma interleukin-10 (IL-10) levels	Assessment of plasma IL-10 concentrations measured by enzyme-linked immunosorbent assay (ELISA).	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Plasma tumor necrosis factor-alpha (TNF-α) levels	Assessment of plasma TNF-α concentrations measured by enzyme-linked immunosorbent assay (ELISA).	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Thiobarbituric acid reactive substances (TBARS) levels	Assessment of lipid peroxidation by measuring TBARS levels in EDTA plasma samples.	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.
Protein carbonylation (CPr) levels	Assessment of oxidative stress through protein carbonylation analysis.	Preoperative period, immediately after surgery before photobiomodulation application, 20 minutes after ICU admission, and on postoperative days 2 to 5 or until hospital discharge.

Collaborators and Investigators

• Sponsor: Federal University of São Paulo

Publications and helpful links

Helpful Links

• No-touch technique for saphenous vein graft harvesting in coronary artery bypass surgery safely improves graft patency: a meta-analysis of randomized controlled trials.
• Oxygen uptake on-kinetics during six-minute walk test predicts short-term outcomes after off-pump coronary artery bypass surgery.
• Effectiveness of low-intensity laser therapy on tissue repair following saphenectomy in patients who underwent coronary artery bypass graft: A randomized, double-blind study.
• SUPERIOR SVG: no touch saphenous harvesting to improve patency following coronary bypass grafting (a multi-Centre randomized control trial, NCT01047449).
• Pedicled no-touch saphenous vein graft harvest limits vascular smooth muscle cell activation: the PATENT saphenous vein graft study.
• Detection and quantification of cytokines and other biomarkers.

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): March 1, 2028

Study Registration Dates

• First Submitted: March 20, 2026
• First Submitted That Met QC Criteria: July 8, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 8, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Wound Healing; Photobiomodulation; Coronary Artery Bypass Grafting; Low-Level Laser Therapy; Saphenous Vein Harvesting; No-Touch Technique
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Heart Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Myocardial Ischemia; Coronary Artery Disease; Therapeutics; Laser Therapy; Phototherapy; Low-Level Light Therapy
• Other Study ID Numbers: 90777725.0.0000.5505

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No