Skeletonised Versus Pedicled Internal Thoracic Artery

Study Overview
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Brief Summary
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It is to date unknown whether Thunderbeat has a place in harvesting the left internal mammary artery (LIMA) and whether skeletonisation is superior to pedicle harvested LIMA. Though, some studies have shown improved flow-rates in the skeletonised graft while others shows compromised blood flow to the thoracic wall after pedicle harvested LIMA. The purpose of this study is to improve the quality of life for patients undergoing coronary artery bypass graft (CABG) operations. The aim of this study is to compare three groups of LIMA harvesting techniques: Pedicled, surgical skeletonised and skeletonised with Thunderbeat to determine the best way to harvest LIMA during CABG operations. The study design is an experimental randomized controlled trial in a single centre. Study population: Adult patients enlisted for elective stand-alone CABG surgery at the Department of Cardiothoracic surgery, Odense University Hospital. Study Unit: Test-days within subject and subject The study will address two main hypotheses in CABG patients: That both the surgical skeletonised and Thunderbeat skeletonised harvesting techniques of LIMA are superior to pedicled harvesting in regards to flowrates and pulsatility index (PI). Skeletonized harvesting of LIMA graft compared to pedicled harvesting improves patient quality of life three days, 30 days, and six months postoperatively.

Official Title
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Skeletonised Versus Pedicled Internal Thoracic Artery - A Randomised Study

Conditions
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Heart Diseases

Intervention / Treatment
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* Procedure: Pedicled
* Procedure: Surgical skeletonised
* Procedure: Thunderbeat skeletonised


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Stand-alone CABG (surgical removal of the left atrial appendage (LAAX) is accepted, since it doesn't affect the graft area) On-pump with cardioplegia (otherwise one cannot be sure of the pressure and perfusion during surgery of the graft) Patients aged >18 Elective surgery (there is a known higher risk of postoperative complications with urgent surgery) Exclusion Criteria: CABG combined with other heart surgery, except from LAAX Previous heart surgery LVEF < 40% (there is a known higher risk of postoperative complications with low LVEF) Known cancers (there is a known higher risk of postoperative complication) Thoracic radiation therapy (there is a known higher risk of postoperative complication) Severe chronic obstructive pulmonary disease (COPD) (there is a known higher risk of postoperative complication) Patients not able to understand written consent Urgent and emergent surgery (there is a known higher risk of postoperative complication)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomised trial
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Pedicled<br>Harvesting of LIMA with its surrounding tissue: fascia, veins, etc | Procedure: Pedicled<br>* Surgical procedure: A prior marking was made on both sides of the LIMA and its veins with bi-polar technique. Hereafter the LIMA and its veins were dissected free with scissor and forceps. Clips were added to all side branches. When the full length of LIMA was obtained, the LIMA and its veins were divided distally by adding clips on the peripheral part of the vessels and proximately dividing by scissor. A vessel-clamp was placed distally and the pedicled LIMA placed in the jugular cavity with a cloth containing papaverine.<br>|
| Active Comparator: Surgical skeletonised<br>Harvesting of LIMA in a naked fashion where you dissect the artery free of the surrounding tissue. | Procedure: Surgical skeletonised<br>* Surgical procedure: The fascia of the LIMA was opened with a scissor. Hereafter the LIMA was dissected free with scissor and forceps, clips on all LIMA side-branches and divided by scissor. When the full length of LIMA was obtained, the LIMA was divided distally by adding clips on the peripheral part of the vessel and proximately dividing by scissor. A vessel-clamp was placed distally, and the skeletonised LIMA placed in the jugular cavity with a cloth containing papaverine.<br>|
| Active Comparator: Skeletonised with Thunderbeat<br>Same as Surgical skeletonised but instead of closing the side branches with clips a surgical tool is used for coagulation of the side-branches. | Procedure: Thunderbeat skeletonised<br>* Surgical procedure: With Thunderbeat the fascia of LIMA was opened. The LIMA was dissected free with Thunderbeat including all side-branches. When the full length of the LIMA was obtained, the LIMA was divided distally by adding clips on the peripheral part of the vessel and proximately dividing by scissor. A vessel-clamp was placed distally, and the skeletonised LIMA placed in the jugular cavity with a cloth containing papaverine.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in flow in LIMA and pulssatility index between the three groups. | mL/ min With transit time flowmetry (Sono TT flowlab), the graft flow and peripheral index (PI) are measured after weaning off the extracorporeal circulation with a systolic pressure aimed at 100 mmHg. The measurements are done with probe size 3 or 4. | Perioperative - After weaning off the extracorporeal circulation just before closing the thorax | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative bleeding | Unit: mL | Postoperative bleeding is measured from the end of the operation to removal of the mediastinal drains in the intensive care unit | 
| Re-operation due to bleeding | Number of patients in each group | Up to 48 hours calculated from the end of primaery surgery | 
| Re-operation due to ischemia | Number of patients in each group | Up to 48 hours calculated from the end of primaery surgery | 
| Pleurocentesis | Number of patients in each group | Up to 10 days calculated from the end of primaery surgery | 
| Myocardial injury - creatine kinase-MB (CK-MB) | Unit: (µg/L) | Routine bloodsample measured four hours after aortic cross clamp removal. | 
| Myocardial injury - cardiac troponin (cTn) | Unit: (ng/L) | Routine bloodsample measured four hours after aortic cross clamp removal. | 
| Differences in pre and post operative regional oxygen saturation on the thorax. | Unit: oxygen saturation (rSO2) | Measured 7 days prior to surgery and again 3 days after surgery | 
| Length of stay on ICU | Unit: Days | Day of surgery to the day of discharge from ICU. Up to 52 weeks | 
| Length of stay in hospital | Unit: Days | Day of surgery to the day of discharge from hospital. Up to 52 weeks | 
| EQ-5D-5L questionnaire: differences in self reported assessment of patient quality of life between the 3 groups | Developed by the EURO-QoF group in 1990 to describe five dimensions of quality of life: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has five levels: no problems, slight problems, moderate problems, severe problems and extreme problems and a visual analogue scale recording the patient's self-rated health. | Questionnaires uptained the week before the date of surgery and again 3, 30, and 180 days after surgery. | 
| Telephone interview - Questions regarding pain, numbness and wound healing around the thoracic incision. | All questions are closed questions and qualitative variables (yes/no) | 180 ± 7 days calculated from the date of surgery. | 
| Rate of readmission to hospital due to Major adverse cardiac and cerebrovascular events (MACCE) - early | Number of deaths in each group | Early (≤30 days) | 
| Rate of readmission to hospital due to Major adverse cardiac and cerebrovascular events (MACCE) - Intermediate | Number of deaths in each group | Intermediate (≤180 days) | 
| Rate of readmission to hospital due to Major adverse cardiac and cerebrovascular events (MACCE) - Long | Number of deaths in each group | Long (≤2 years) | 
| Rate of mortality due to cardiac event - Early | Number of deaths in each group | Early (≤30 days) | 
| Rate of mortality due to cardiac event - Intermediate | Number of deaths in each group | Intermediate (≤180 days) | 
| Rate of mortality due to cardiac event - Iong | Number of deaths in each group | Long (≤2 years) | 
| Rate of all-cause mortality - Early | Number of deaths in each group | Early (≤30 days) | 
| Rate of all-cause mortality - Intermediate | Number of deaths in each group | Intermediate (≤180 days) | 
| Rate of all-cause mortality - long | Number of deaths in each group | Long (≤ 2 years) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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coronary artery diseases, left internal mammary artery, LIMA harvesting, flow, quality of life