Date of Award

Spring 2020

Degree Name

Master of Medical Science (Physician Assistant)

Department

Physician Assistant; College of Health Sciences

First Advisor

Renee Langstaff

Abstract

Abstract

Introduction: Systolic heart failure is a chronic condition in which there is a decrease in the heart’s ability to pump blood to the body. While there are several treatments for the symptoms of heart failure, the only curative treatment for most causes of chronic heart failure is a heart transplant. Due to the limited number of heart donors, 72.2% of patients in need of a heart transplant in 2017 spent up to 2 years waiting for a transplant. Mechanical circulatory support has been used to increase patient survival to transplantation. In the past, these machines were external devices that limited patients to hospitals while they waited for a transplant. Recently, devices have been created that are implantable, with the purpose of increasing patient’s quality of life by allowing for hospital discharge. Therefore, this review compares the use of Syncardia’s total artificial heart to Thoratec’s implantable ventricular assist device (I) in waitlist survival (O) in adult patients in biventricular systolic heart failure (P).

Methods: A literature search was conducted through Google Scholar in November 2018. A total of seven articles consisting of two prospective cohort and five retrospective cohort studies were selected based on publication date, type and brand of ventricular support device used, and sample population.

Results: The evidence collected by the three studies directly comparing biventricular assists devices as a whole to Syncardia’s total artificial heart showed no significant difference in survival to transplantation. One of the four supplementary studies independently showed significant survival to transplantation in Thoratec implantable ventricular assist device patients and two studies independently showed significant survival to transplantation in Syncardia total artificial heart patients. Six of the seven total studies showed survival to successful transplantation in the total artificial heart or the implantable ventricular assist device after a year on mechanical circulatory support.

Discussion: Of the three studies comparing survival to transplantation between biventricular assist device patients and total artificial heart patients, no significant differences were found. Of the other four articles examining overall survival to transplantation on the total artificial heart and the implantable assist devices, all the studies showed significant positive results. Due to the limited sample sizes and inability to randomize samples, further research on the topic is necessary.

Conclusion: In 2017, 3,529 adults in America were on the United Network for Organ Sharing (UNOS) list waiting for a donor heart. Ventricular assist devices are often used to bridge patients with severe heart failure to transplantation. The seven studies selected for review found that there is not a significant difference in waitlist survival between patients with a Syncardia total artificial heart and a Thoratec implantable ventricular assist device. While more research is recommended to create a set of guidelines for biventricular assist device selection, currently the decision is between a patient and their clinical care team.

Additional Files

Davenport Final Poster.pptx (2715 kB)
Poster summary of capstone.

Davenport Capstone Presentation.mp4 (7276 kB)
Video explanation of the capstone project..

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The Efficacy of Thoratec Implantable Ventricular Assist Devices Compared to Syncardia Total Artificial Hearts as Bridge-to-Transplantation Therapy in Adults with Biventricular Heart Failure

Abstract

Introduction: Systolic heart failure is a chronic condition in which there is a decrease in the heart’s ability to pump blood to the body. While there are several treatments for the symptoms of heart failure, the only curative treatment for most causes of chronic heart failure is a heart transplant. Due to the limited number of heart donors, 72.2% of patients in need of a heart transplant in 2017 spent up to 2 years waiting for a transplant. Mechanical circulatory support has been used to increase patient survival to transplantation. In the past, these machines were external devices that limited patients to hospitals while they waited for a transplant. Recently, devices have been created that are implantable, with the purpose of increasing patient’s quality of life by allowing for hospital discharge. Therefore, this review compares the use of Syncardia’s total artificial heart to Thoratec’s implantable ventricular assist device (I) in waitlist survival (O) in adult patients in biventricular systolic heart failure (P).

Methods: A literature search was conducted through Google Scholar in November 2018. A total of seven articles consisting of two prospective cohort and five retrospective cohort studies were selected based on publication date, type and brand of ventricular support device used, and sample population.

Results: The evidence collected by the three studies directly comparing biventricular assists devices as a whole to Syncardia’s total artificial heart showed no significant difference in survival to transplantation. One of the four supplementary studies independently showed significant survival to transplantation in Thoratec implantable ventricular assist device patients and two studies independently showed significant survival to transplantation in Syncardia total artificial heart patients. Six of the seven total studies showed survival to successful transplantation in the total artificial heart or the implantable ventricular assist device after a year on mechanical circulatory support.

Discussion: Of the three studies comparing survival to transplantation between biventricular assist device patients and total artificial heart patients, no significant differences were found. Of the other four articles examining overall survival to transplantation on the total artificial heart and the implantable assist devices, all the studies showed significant positive results. Due to the limited sample sizes and inability to randomize samples, further research on the topic is necessary.

Conclusion: In 2017, 3,529 adults in America were on the United Network for Organ Sharing (UNOS) list waiting for a donor heart. Ventricular assist devices are often used to bridge patients with severe heart failure to transplantation. The seven studies selected for review found that there is not a significant difference in waitlist survival between patients with a Syncardia total artificial heart and a Thoratec implantable ventricular assist device. While more research is recommended to create a set of guidelines for biventricular assist device selection, currently the decision is between a patient and their clinical care team.

 
 

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