Transplant patients are among those at highest risk of adverse outcomes when receiving a stent to address a blockage in an artery. Compared with the general public, these patients have a much higher rate of restenosis, a side effect of stenting in which the artery becomes re-blocked because of an exaggerated scarring process at the stenting site.
New research by UCLA researchers and colleagues has found that heart transplant patients who develop restenosis after receiving a stent have poor long-term survival. Their study, one of the largest and longest follow-up studies of this patient population, appeared in the June 15 edition of the American Journal of Cardiology.
"The findings point to the need for improvements in prevention and treatment of transplant coronary artery disease that may help reduce restenosis for patients who require later cardiac procedures like stenting," said Dr. Michael Lee, an assistant professor of cardiology at the David Geffen School of Medicine at UCLA.
A stenting procedure begins with an angioplasty, in which a catheter is placed in an artery of the groin and a tiny wire is snaked up through the artery to the blocked area of the heart. The clogged artery is cleaned out, and then a stent — a tiny wire-mesh tube — is passed up through the artery and deployed to keep the artery open, allowing blood to flow freely through the heart again.
Currently, there are no guidelines or treatment recommendations for in-stent restenosis for transplant coronary artery disease, Lee said. He suggests that a scoring system to help pinpoint risks might help identify good candidates for stenting and other catheter-based procedures.
For the study, Lee and his team followed 105 heart transplant patients who underwent a stent procedure at UCLA Medical Center between 1995 and 2009. Patients received either a bare metal stent or, in the later years of the study, a newer medication-coated stent that can help impede restenosis development.
The team found that patients at a seven-year follow-up who had not developed in-stent restenosis were further from an end-point of death, heart attack or repeat transplantation (63.2 percent) than patients who had developed restenosis (27.9 percent). This was primarily due to a lower survival rate in patients who developed restenosis (38.5 percent) compared to patients who did not (84.2 percent).
According to Lee, typically up to 50 percent of heart transplant patients who receive a medication-coated stent develop restenosis, compared with only 5 to 10 percent of the general population.
Researchers note that the exact mechanism that heightens the risk of death and heart attack and increases the need for additional transplant in patients with transplant coronary artery disease who develop in-stent restenosis is not known.
Lee added that organ rejection may contribute to transplant coronary disease and play a role in the increased risk of mortality. The development of blood clots in the arteries, known as intracoronary thrombus, may also contribute to mortality.
"We may find that development of restenosis in heart transplant patients may be a marker of a more aggressive inflammatory response and part of transplant rejection," Lee said.
Further studies will help better understand the role of other factors in developing transplant coronary artery disease and in-stent restenosis.
No outside funding was used for the study.
Other study authors include Richard Cheng of Ronald Reagan UCLA Medical Center, David E. Kandzari of the Piedmont Heart Institute in Atlanta, and Ajay J. Kirtane of Columbia University Medical Center/New York–Presbyterian Hospital in New York.
For more news, visit the UCLA Newsroom and follow us on Twitter.
Rachel Champeau | EurekAlert!
Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University
The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy