As reported by McGowan Institute for Regenerative Medicine
faculty member Robert Kormos, MD, the growth of the Artificial Heart Program at the University of Pittsburgh has led to advances in clinical understanding and outcome, new research collaborations, and continued international acknowledgment. On August 4, 2009, the Artificial Heart Program implanted Pittsburgh’s first Heartware centrifugal left ventricular assist device (LVAD pictured top). This procedure was performed for end-stage dilated cardiomyopathy in a 57-year-old male as a bridge to cardiac transplantation. The device, which is currently under investigation by the FDA, has the benefit of not requiring the surgeon to make an abdominal incision or pocket for the device, as it sits uniquely within the pericardial space. The immediate benefit appears to be less invasive surgery with a lower risk for bleeding and infection.
The advantages of centrifugal design have been demonstrated through experience over the past 2 years with the Ventrassist LVAD (pictured bottom), which showed more physiologic response than the traditional axial-flow rotary blood pumps. It also presented a broader range of flows leading to easier management of the patient following discharge from the hospital with the implanted LVAD.
The implantation of the Heartware LVAD represents a milestone for the program, which aims to match the most advanced technology with patient need for circulatory support in conditions of end-stage heart failure. The program continues to grow since its inception in 1985. Approximately 57 implants have been performed in 2008, and, as of this writing, 37 devices have been utilized in 2009.
The selection of devices has gradually changed from the older pulsatile systems to predominantly rotary pumps, which have been accompanied by a higher success rate to transplantation as well as better post-transplant survival. Data demonstrates that post-transplant survival at 3 years is no different between those who required a VAD bridge and those who have received a heart transplant alone.
Recently, the Artificial Heart Program began a collaborative effort that includes the Heart-Lung and Esophageal Program as well as the Weight-Loss Surgery Program for patients who have both morbid obesity and congestive heart failure. The program currently has enrolled two patients who received a Heartmate II LVAD as destination therapy and will then undergo gastric bypass surgery. If successful, this will result in making cardiac transplantation available to those who are considered non-candidates based upon morbid obesity.
Over the years the program has accumulated experience with over 530 pump implants, which resulted in over 100 patient years of experience with 10,000 days (28 years) of outpatient care. Through the combined efforts of the nursing team and that of Vital Engineering – the biomedical engineering group – the Artificial Heart Program was successful in receiving last year’s Joint Commission Gold Seal of Approval for Destination Therapy. Since then the quality assurance program continues to demonstrate a significant reduction in post-implant infections and a reduced length of inpatient stay from nearly 80 days in 2007 to 30 days or less in 2008. The program continues to forge new research frontiers in understanding the ability of the heart to recover under LVAD support and has had success in this regard with two patients this year, as shown.
Vital Engineering continues to demonstrate its expertise in maintaining support contracts at several outside facilities, allowing the program to renew contracts with Evaheart, Sunshine Heart, Wake Forest University Baptist Medical Center, and the Thoratec Corp. There are also a number of ongoing opportunities with industries such as Maquet Corporation, Heartware, and Alung Technologies, as well as academic institutions, including Texas A&M Medical Center, NIH Heart Center at Suburban Hospital, and the Veterans Administration Hospital System.
The research efforts of the faculty continue to expand. In collaboration with the Cardiovascular Institute at UPMC and under the direction of cardiologist Dr. Charles McTiernan, the Artificial Heart Program is developing one of the largest pre-VAD and post-VAD cardiac tissue banks in North America. Through his work and that of Dr. Dennis McNamara, we have a much greater understanding of the cellular basis for myocardial recovery. Dr. McNamara’s work has also been valuable in identifying the genetic changes accompanying congestive heart failure and how those are modified by the LVAD. Dr. Jeffery Teuteberg directs major clinical research efforts, while Dr. John Gorcsan and his team direct a multi-center effort to document the predictability of myocardial recovery utilizing echocardiography. Dr. Christian Bermudez, whose interest lies in the surgical treatment of congestive heart failure surgery, is examining the outcome of patients supported acutely with mechanical circulatory assistance and extracorporeal membrane oxygenation (ECMO), and he is developing strategies of application to maximize outcome. Dr. Mary Amanda Dew and Dr. Robert Kormos were successful in helping a University of Pittsburgh Medical Student, Elizabeth Genovese, to obtain a Doris Duke Foundation grant to study the adverse events associated with VADs and how they affect outcome. In collaboration with the McGowan Institute and Dr. William Wagner, University of Pittsburgh Bioengineering Department student, Josh Woolley, is conducting a study that examines the effects of rotary blood pumps on the coagulation system of the blood in particular platelet dysfunction.
Dr. Kormos is also helping to spearhead the Interagency Registry for Mechanical Circulatory Support (INTERMACS) as a co-principal investigator with Dr. James Kirklin at the University of Alabama and Dr. Lynne Warner-Stevenson from Harvard. This registry now contains information on nearly 2,000 approved assist devices used as bridge to transplantation, recovery, and destination therapy, and Dr. Kormos, as the Chair of the Adverse events subcommittee, has succeeded in establishing a set of definitions now adopted by the FDA and industry and clinical investigators worldwide.
Illustrations: Heartware (top) and Ventracor (bottom).
Artificial Heart Program
UPMC Cardiovascular Institute
UPMC Heart, Lung, and Esophageal Surgery Institute
Bariatric Center of Excellence, the Minimally Invasive Bariatric and General Surgery Program at Magee-Womens Hospital of UPMC
Bio: Dr. Robert Kormos
Bio: Dr. Charles McTiernan
Bio: Dr. Dennis McNamara
Bio: Dr. Jeffery Teuteberg
Bio: Dr. Mary Amanda Dew
Bio: Dr. William Wagner