Safety and Effectiveness of the Medtronic Resting Heart Bypass System in Heart Surgery Patients

Cardiopulmonary Bypass Clinical Trial

Official title:

A Prospective Randomized Study of the Safety and Effectiveness of the Medtronic Resting Heart System

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00303641
• Other study ID #: R-04-424
• Status: Completed
• Phase: Phase 1
• First received: March 15, 2006
• Last updated: August 25, 2017
• Start date: November 2004
• Est. completion date: February 2006

Study information

• Verified date: August 2017
• Source: Lawson Health Research Institute
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to determine if the Medtronic Resting Heart Bypass system is safer and results in less inflammatory reaction than traditional bypass machines used in coronary artery bypass surgery. We hypothesize that the new Medtronic Resting Heart System is safer and results in much less systemic inflammatory reaction in comparison to the standard cardiopulmonary bypass systems currently in use.

Description:

Cardiopulmonary bypass (CPB) has played an extremely crucial role in coronary artery bypass grafting (CABG) surgery for the past five decades. During CABG, the CPB machine enables the surgeon to stop the heart and perform the surgery in a bloodless operating field. The CPB machine essentially takes over the job of the heart by oxygenating the blood and then perfusing the entire body. In patients undergoing CABG surgery with CPB, a systemic inflammatory reaction occurs when the blood is taken out of the body and circulated through the CPB machine. This inflammatory reaction is believed to increase postoperative morbidity and prolong hospital stay. The systemic inflammatory reaction results in activation of the complement, coagulation, fibrinolytic and kallikrein cascades, it activates leukocytes and endothelial cells causing expression of adhesion molecules and results in the release of inflammatory mediators such as cytokines. This inflammatory reaction during CPB leads to vasodilation, increased interstitial fluid and can affect organs such as the heart, lungs, brain and kidneys resulting in their dysfunction(s). Elimination of CPB in patients undergoing CABG surgery has resulted in reduction of this inflammatory response. Unfortunately, not all patients are able to undergo CABG without the use of CPB.

Most conventional CPB systems also use cardiotomy suction which returns all the blood collected in the operative field back to the CPB reservoir and then eventually returns it to the patient. This blood is rich in inflammatory mediators and small particles because it has been activated by surgical trauma and by the proteins lining the wound cavity. Returning this blood back into the CPB circuit results in further circulation of inflammatory mediators. Removal of the cardiotomy suction from the CPB system could potentially decrease the inflammatory mediators and reduce the inflammatory response during CPB.

Recently, there have been attempts to decrease the inflammatory reaction caused by the use of CPB by developing better, more effective systems. The Medtronic Resting Heart System is very similar to conventional CPB systems and has been approved for clinical use both in Canada and the United States. It has some potential advantages over traditional bypass machines which include; 1)a fully closed-to-air system that does not allow an air-blood interface which could prevent blood activation, 2)it does not have cardiotomy suction and therefore prevents air, lipids or particulate emboli from being re-introduced into the patient's circulation, 3)it minimizes hemodilution by using smaller and low-prime circuits, possibly decreasing the need for postoperative blood transfusion, 4)the CPB circuit, which is the blood-contacting surface, is coated with Carmeda Bioactive Surface (a heparin bioactive surface), that mimics critical characteristics of vascular endothelium and may prevent further blood activation, and 5)it has an active venous air detector and removal device (VARD) that detects venous air and automatically removes the air which may prevent blood activation. All of these elements are potential benefits which may further reduce the morbidity and inflammation associated with CABG surgery.

Thus far to our knowledge, there have been no studies looking at the inflammatory reaction and morbidity in patients undergoing CABG procedures using more improved cardiopulmonary bypass machines. We are therefore proposing a prospective, randomized trial of the safety and effectiveness of the Medtronic Resting Heart system in CABG surgery.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 60
• Est. completion date: February 2006
• Est. primary completion date: November 2005
• Accepts healthy volunteers: No
• Gender: All
• Age group: 30 Years to 85 Years

Eligibility

Inclusion Criteria:

• Consenting patients undergoing elective surgical coronary artery bypass grafting (CABG) with use of the cardiopulmonary bypass machine

Exclusion Criteria:

• Patients unable to provide written informed consent

• Emergency CABG surgery

• Concomitant CABG + Valvular surgery

• Off-pump CABG surgery

Related Conditions & MeSH terms

• Cardiopulmonary Bypass
• Coronary Artery Bypass Surgery

Intervention

Device:
• Medtronic Resting Heart Bypass System

Locations

Country	Name	City	State
Canada	London Health Sciences Centre, University Hospital	London	Ontario

Sponsors (2)

Lead Sponsor	Collaborator
Lawson Health Research Institute	Medtronic

Country where clinical trial is conducted

Canada, 

References & Publications (9)

Aldea GS, Soltow LO, Chandler WL, Triggs CM, Vocelka CR, Crockett GI, Shin YT, Curtis WE, Verrier ED. Limitation of thrombin generation, platelet activation, and inflammation by elimination of cardiotomy suction in patients undergoing coronary artery bypass grafting treated with heparin-bonded circuits. J Thorac Cardiovasc Surg. 2002 Apr;123(4):742-55. — View Citation

Edmunds LH Jr. Inflammatory response to cardiopulmonary bypass. Ann Thorac Surg. 1998 Nov;66(5 Suppl):S12-6; discussion S25-8. Review. — View Citation

Fransen E, Maessen J, Dentener M, Senden N, Geskes G, Buurman W. Systemic inflammation present in patients undergoing CABG without extracorporeal circulation. Chest. 1998 May;113(5):1290-5. — View Citation

Gu YJ, Mariani MA, van Oeveren W, Grandjean JG, Boonstra PW. Reduction of the inflammatory response in patients undergoing minimally invasive coronary artery bypass grafting. Ann Thorac Surg. 1998 Feb;65(2):420-4. — View Citation

Jewell AE, Akowuah EF, Suvarna SK, Braidley P, Hopkinson D, Cooper G. A prospective randomised comparison of cardiotomy suction and cell saver for recycling shed blood during cardiac surgery. Eur J Cardiothorac Surg. 2003 Apr;23(4):633-6. — View Citation

Kaza AK, Cope JT, Fiser SM, Long SM, Kern JA, Kron IL, Tribble CG. Elimination of fat microemboli during cardiopulmonary bypass. Ann Thorac Surg. 2003 Feb;75(2):555-9; discussion 559. — View Citation

Kirklin JK, Westaby S, Blackstone EH, Kirklin JW, Chenoweth DE, Pacifico AD. Complement and the damaging effects of cardiopulmonary bypass. J Thorac Cardiovasc Surg. 1983 Dec;86(6):845-57. — View Citation

Matata BM, Sosnowski AW, Galiñanes M. Off-pump bypass graft operation significantly reduces oxidative stress and inflammation. Ann Thorac Surg. 2000 Mar;69(3):785-91. — View Citation

Wehlin L, Vedin J, Vaage J, Lundahl J. Activation of complement and leukocyte receptors during on- and off pump coronary artery bypass surgery. Eur J Cardiothorac Surg. 2004 Jan;25(1):35-42. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	C-reactive protein
Primary	Cell count
Primary	Cytokine levels
Primary	Complement
Secondary	Postoperative blood loss, units of blood transfused, re-operation for bleeding, chest tube drainage, length of ICU stay, neurologic and renal function, infection, atrial fibrillation and overall length of postoperative hospital stay

External Links

•   London Health Sciences Centre, University Hospital, Division of Cardiac Surgery