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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00303641
Recruitment Status : Completed
First Posted : March 17, 2006
Last Update Posted : August 28, 2017
Information provided by (Responsible Party):
Lawson Health Research Institute

Brief 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.

Condition or disease Intervention/treatment Phase
Coronary Artery Bypass Surgery Cardiopulmonary Bypass Device: Medtronic Resting Heart Bypass System Phase 1

Detailed 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.

Study Type : Interventional  (Clinical Trial)
Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single
Primary Purpose: Treatment
Official Title: A Prospective Randomized Study of the Safety and Effectiveness of the Medtronic Resting Heart System
Actual Study Start Date : November 2004
Actual Primary Completion Date : November 2005
Actual Study Completion Date : February 2006

Resource links provided by the National Library of Medicine

Primary Outcome Measures :
  1. C-reactive protein
  2. Cell count
  3. Cytokine levels
  4. Complement

Secondary Outcome Measures :
  1. 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

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   30 Years to 85 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00303641

Canada, Ontario
London Health Sciences Centre, University Hospital
London, Ontario, Canada, N6A 5A5
Sponsors and Collaborators
Lawson Health Research Institute
Principal Investigator: Bob Kiaii, MD, FRCSC Department of Cardiac Surgery, University of Western Ontario and the London Health Sciences Centre, University Hospital

Additional Information:

Responsible Party: Lawson Health Research Institute Identifier: NCT00303641     History of Changes
Other Study ID Numbers: R-04-424
First Posted: March 17, 2006    Key Record Dates
Last Update Posted: August 28, 2017
Last Verified: August 2017

Keywords provided by Lawson Health Research Institute:
Cardiopulmonary bypass
Inflammatory reaction