New Saint Louis University research has found that beta blockers, a class of drugs used to prevent the progression of heart failure and manage arrhythmias (irregular heart beat) and hypertension (high blood pressure), are underused in heart failure patients who receive implantable cardiac devices.

Failure to take beta blockers prior to implanting a cardiac device can affect the patient’s overall outcome and survival rate, says Paul Hauptman, M.D., SLUCare cardiologist and professor of internal medicine at Saint Louis University School of Medicine and lead author of the study.

Additionally, beta blocker use may eliminate the need for the cardiac device entirely by improving heart function. Multiple clinical practice guidelines, including those of the American College of Cardiology/American Heart Association, support the use of beta blockers.

The research, which was published in the March 2010 issue of Circulation: Cardiovascular Quality and Outcomes, used a large multi-state managed care database to examine the use of beta blockers both 90 days prior to and 180 days following the implantation of the device. When possible, researchers removed patients from the database who would not have qualified for beta blockers because of an underlying health issue, such as asthma, or because they received the device in an emergency situation.

Of the 2,766 patients included in the study, one third did not take beta blockers at any time in the 90 days before receiving a cardiac device. Additionally, less than 40 percent of the patients fell into the high use category, which was defined as having prescriptions for beta blockers that covered at least 80 percent of the 90 days prior to the procedure. The research found a modest increase of beta blocker use following the device procedure.

“Current guidelines for cardiac devices stress the importance of establishing optimal therapy, which includes the use of beta blockers, before considering a patient a candidate for the invasive procedure,” Hauptman said.

“Cardiac devices alone are not the answer. Implantable defibrillators in particular function as a safety net; they provide protection in the event the heart would stop beating. Beta blockers, on the other hand, are a therapy. They can prevent progression of heart failure.”

One of the criteria used to select candidates for cardiac devices is the ejection fraction, which refers to the fraction of blood pumped out of the heart with each heart beat. Beta blockers can improve a patient’s ejection fraction and decrease the risk of sudden death. In fact, in some cases, taking beta blockers can improve ejection fraction so greatly that the patient no longer needs a cardiac device, Hauptman says.

While the research shows that less than 40 percent of patients take beta blockers for the recommended 90 days prior to receive a cardiac device, what is less clear are the reasons behind the lack of adherence.

“It’s probably a combination of two factors: physicians are not prescribing the medication the way they should and patients may be non-compliant. From the proverbial 30,000 foot view, though, it doesn’t matter why,” Hauptman explained. “We need to have systems in place to ensure that patients are on optimal medical therapy prior to receiving a device.”

Hauptman says the issue comes down to improving patient care and managing health care cost.
“Implantable cardiac devices are invasive and very expensive. We have a great opportunity to improve the way we care for heart failure patients. Plus, we can save money along the way,” Hauptman said.

A heart patient’s own skin cells soon could be used to repair damaged cardiac tissue thanks to pioneering stem cell research of the University of Houston’s newest biomedical scientist, Robert Schwartz.

His new technique for reprogramming human skin cells puts him at the forefront of a revolution in medicine that could one day lead to treatments for Alzheimer’s, diabetes, muscular dystrophy and many other diseases.

Schwartz brings his ground-breaking research to UH as the Cullen Distinguished Professor of Biology and Biochemistry and head of UH’s new Center for Gene Regulation and Molecular Therapeutics. He also is affiliated with the Texas Heart Institute at St. Luke’s Episcopal Hospital in the Texas Medical Center, where he is director of stem cell engineering.

“Professor Schwartz’s work will save lives, and his decision to pursue this pioneering research at UH is a big leap forward on our way to Tier-One status,” said John Bear, dean of the UH College of Natural Sciences and Mathematics. “Together with the many other outstanding scientists we’ve assembled here, Schwartz will help make this university a major player in medical research.”

Schwartz devised a method for turning ordinary human skin cells into heart cells. The cells developed are similar to embryonic stem cells and ultimately can be made into early-stage heart cells derived from a patient’s own skin. These then could be implanted and grown into fully developed beating heart cells, reversing the damage caused by previous heart attacks. These new cells would replace the damaged cardiac tissue that weakens the heart’s ability to pump, develops into scar tissue and causes arrhythmias. Early clinical trials using these reprogrammed cells on actual heart patients could begin within one or two years.

Although Schwartz is not the first scientist to turn adult cells into such stem cells, his improved method could pave the way for breakthroughs in other diseases. Schwartz’s method requires fewer steps and yields more stem cells. Armed with an effective way to make induced stem cells from a patient’s own skin, scientists can then begin the work of growing all kinds of human cells.

For example, new brain cells could treat Alzheimer’s patients or those with severe brain trauma, or a diabetic could get new insulin-producing cells in the pancreas. Generating new kidney, lung or liver tissue is also possible, with scientists even being able to one day grow an entirely new heart or other organ from these reprogrammed cells. Additionally, Schwartz and his team are working on turning induced stem cells into skeletal muscle cells to treat muscular dystrophy.

“We’re trying to advance science in ways folks never even dreamed about,” Schwartz said. “The idea of having your own bag of stem cells that you can carry through life and use for tissue regeneration is at the very cutting edge of science.”

This latest biomedical hire is a major step in the UH Health Initiative, an effort aimed at having the university become a world-class center for medical research. Creating new cross-disciplinary academic and health-related research opportunities for faculty and students is crucial to this initiative, as are collaborations with other Texas Medical Center member institutions. One of its top goals is to increase the amount of sponsored research expenditures awarded to UH, which is a key factor in attaining Tier-One status.

“Dr. Schwartz will expand UH’s expertise in promising new areas of scientific discovery to alleviate human disease. By recruiting premier scientists like Schwartz, UH is fast becoming a major player in the regional biomedical research community,” said Kathryn Peek, assistant vice president of University Health Initiatives at UH.

A study published Online First reports that cardiopulmonary resuscitation (CPR) by bystanders increases the likelihood of survival for children who have cardiac arrests outside of a hospital. In addition, CPR that includes chest compressions with rescue breathing is more important for non-cardiac causes of cardiac arrest, such as drowning, than chest compressions alone. The study is the work of Dr Taku Iwami, Kyoto University Health Service, Kyoto, Japan, and colleagues.

CPR has been shown to improve survival rates. The American Heart Association recommends CPR by bystanders with chest compression only for adults who have cardiac arrests outside of a hospital. But, such an association for children has not been confirmed because the majority of earlier studies have not had a sufficient sample size.

This population-based cohort study was nationwide. The researchers enrolled 5,170 children aged 17 years or younger who had had a cardiac arrest outside of a hospital. Data were obtained on whether or not the children had been given CPR, and if so, whether or not it was compression-only CPR or CPR with rescue breathing. The primary endpoint was a favorable neurological outcome at one month after the cardiac arrest. This was defined by a Glasgow-Pittsburgh cerebral performance category of:

• 1 :good performance
• 2 :moderate disability

Results indicate that a favorable neurological outcome was about three times more likely for children who had been given any CPR by a bystander than for those who had not. Conventional CPR with rescue breathing in children whose cardiac arrests had a non-cardiac cause was more likely to improve survival than compression-only CPR. Both types of CPR had similar effect for children whose arrests were cardiac in cause.

The authors remark: “Unlike previous studies that were underpowered to show this important association, our study is sufficiently large to identify the important beneficial effect of bystander CPR on survival outcomes after paediatric cardiac arrest.”

They write in conclusion: “Our data lead us to lend support to a double CPR training strategy: compression-only CPR training for most people to increase bystander CPR by bystanders, and conventional CPR (chest compression plus rescue breathing) training for individuals who are most likely to witness children who have cardiac arrests with non-cardiac causes, such as medical professionals, lifeguards, school teachers, families with children, and families with swimming pools.”

In an associated note, Dr Jesús López-Herce and Dr Angel Carrillo Alvarez, Pediatric Intensive Care Service, Hospital General Universitario Gregorio, Madrid, Spain, comment that this study “confirms that early bystander-initiated CPR is one of the fundamental factors to improve prognosis, in adults and children.”

They mention that Iwami et al’s information: “underline the importance of not extrapolating findings from adults to children, because cardiac arrest in children has specific characteristics. In adults, 65% of out-of-hospital cardiac arrests are of cardiac origin, whereas in children at least 71% are of non-cardiac origin. 71% is probably an underestimate because the diagnosis of cardiac origin was by exclusion in today’s study and, in other studies, cardiac causes accounted for less than 10% of cases.”

They say in closing: “Chest compression plus ventilation should continue to be the standard, a technique that should be taught to the whole population.”

“Conventional and chest-compression-only cardiopulmonary resuscitation by bystanders for children who have out-of-hospital cardiac arrests: a prospective, nationwide,population-based cohort study”

“Nanoburrs” are nanoparticles coated with a sticky protein that makes them cling onto artery walls while they slowly release drugs: the US researchers who are developing them hope they will one day provide an alternative to drug-releasing stents in fighting heart disease.

The researchers, based at the Massachusetts Institute of Technology, (MIT) and Harvard Medical School, wrote about how they developed and tested the nanoburrs as potential drug-releasing agents for targeting and repairing damaged blood vessels in a paper that was published online on 19 January in the Proceedings of the National Academy of Sciences.

The nanoburrs can release their drug payload over several days, and could be used to deliver drugs to treat treat atherosclerosis and other inflammatory cardiovascular diseases, the researchers told the press.

They hope one day the nanoburrs can be used with vascular stents, the standard of care for most cases of clogged and damaged arteries, and in some cases may even replace stents in locations they are not well suited for, such as near a fork in the artery.

Co-author Omid Farokhzad, associate professor at Harvard Medical School, said that the nanoparticles are one of the first designed to home in precisely on damaged vascular tissue. He and co-author Robert Langer, a professor at MIT, have already developed nanoparticles that target and destroy tumors.

Langer said:

“This is a very exciting example of nanotechnology and cell targeting in action that I hope will have broad ramifications.”

The researchers designed the nanoburrs to target a specific structure in the artery wall, the basement membrane, which only becomes exposed when the walls are damaged.

In the study they used a drug called paclitaxel that inhibits cell division and helps prevent the growth of scar tissue that can clog arteries.

The nanoburrs are 60 nanometer-diameter spheres (the head of a pin is about 1 million nanometers), and comprise three layers: an inner core, a middle layer and an outer coating.

The inner core contains the drug payload and a polymer chain called PLA. The middle layer is made of a fatty material, soybean lecithin, and the outer coating is a polymer, PEG which protects the nanoburr as it travels through the bloodstream.

The drug release is controlled by varying the length of the PLA chain in the core: the longer the chain, the longer the duration of the release, which occurs through a reaction called ester hydrolysis whereby the drug becomes detached from the polymer.

To make the “burrs”, the researchers screened a library of short peptide sequences to find one that bound most effectively to molecules on the surface of the arterial basement membrane. They selected the most effective one, the seven-amino-acid sequenced C11, to coat the outer layer of the nanospheres.

Uday Kompella, professor of pharmaceutical sciences at the University of Colorado, who was not involved with the study, said the fact the targeted peptides are attached to an outer shell and not directly to the drug-carrying core, which would require a more complicated chemical reaction, could make it easier to manufacture the nanoburrs. He said this design also reduced the risk of bursting and releasing the drug too soon.

The researchers said they have managed to achieve drug release periods lasting 12 days in cultured cells.

They also injected the nanoburrs intravenously into the tails of rats and showed they reached their intended target: the damaged walls of the left carotid artery (the vessel that supplies the head and neck with oxygenated blood). They found that the nanoburrs bound to the damaged walls at twice the rate of non-targeting particles.

The authors wrote that:

“The nanoparticles inhibited human aortic smooth muscle cell proliferation in vitro and showed greater in vivo vascular retention during percutaneous angioplasty over nontargeted controls.”

Lead author Juliana Chan, a graduate student in Langer’s lab at MIT, said that if introavenously injectable particles that deliver drugs over a longer period were available, patients wouldn’t have to undergo repeated and invasive injections directly into the affected area.

Mark Davis, professor of chemical engineering at Caltech, and who was not involved in the study, told the press that this work is a promising step toward developing new treatments for cardiovascular and other diseases:

“If they could do this in patients — target particles to injured areas — that could open up all kinds of new opportunities,” said Davis.

A growing body of research continues to warn of the potential long-term effects of radiation exposure for patients and medical providers during such imaging procedures as x-rays and computed tomography (CT) scans, both of which are traditionally used with certain heart procedures.

Now researchers at the University of Virginia Health System have developed a promising x-ray free technique to treat a common heart disorder called atrial fibrillation – a breakthrough that could all but eliminate radiation exposure to patients and their medical providers.

“One of the most exciting things about our research is the direct impact on patient care and safety,” says John D. Ferguson, MD, associate professor of cardiology in the UVA School of Medicine. The study, led by Ferguson, appears in the December 2009 issue of Circulation. “Cardiac interventions continue to evolve toward lower risk procedures, and this study is another huge step in that direction.”

More than two million Americans suffer from atrial fibrillation (AF), a condition characterized by an irregular heart rate that can lead to weakness, blood clotting and even stroke.

In order to regulate the heart’s rhythm, physicians commonly perform a catheter ablation – a procedure in which doctors use x-ray fluoroscopy to guide a catheter, or flexible tube, to the affected area of the heart. The procedure typically lasts three to four hours, leaving patients and medical providers exposed to significant radiation.

But Ferguson’s research team has developed and successfully tested a new technique to perform catheter ablation of AF using an ultrasound catheter (intracardiac echocardiography) and electroanatomic mapping without the use of x-ray fluoroscopy for the entire procedure.

Using an ultrasound catheter within the heart, physicians can obtain high resolution images of the heart and other key anatomic structures. This provides complete visualization at all times of the catheter’s location, allowing physicians to steer the tube to affected target areas while avoiding injury to key cardiac structures.

The novel technique also uses a computer mapping system, which displays in 3D the image of the heart and the catheter’s location and allows physicians to record precise location points along the catheter’s path.

And to further eliminate radiation exposure in AF patients, the new technique uses cardiac MRI instead of CT scans for all required imaging prior to the procedure. Researchers performed the novel technique in a pilot study on 21 consecutive patients referred to the UVA Atrial Fibrillation Center.

“Larger studies are needed to confirm the safety of the procedure, but the concept that you can perform complex electrophysiology procedures without any use of x-ray is outstanding,” says Brian Annex, MD, chief of the UVA Division of Cardiology.

“This research is a ground-breaking step in our efforts to minimize radiation exposure to all patients. This is a major goal that is especially critical to those most vulnerable — patients who would otherwise require excessive radiation due to weight, women of child bearing potential, and of course children and younger adults,” Annex says.

“This procedure is currently being used in selected patients at UVA Medical Center while ongoing investigations are underway to establish the full spectrum of patients who we hope can receive this type of approach in the near future.”

A new approach to common cardiac procedures called transradial angiography might lead to reduced patient complications and recovery time and decreased hospital costs.

Cardiologists at the University of Illinois and Jesse Brown VA medical centers are among the first in the Chicago area to offer the approach to heart angiograms and clearing blocked arteries.

In the procedure, a catheter is threaded through the small radial artery in the wrist rather than the larger femoral artery in the groin.

“It’s a simple change that has a dramatic impact on the experience and recovery of the patient,” said Dr. Adhir Shroff, assistant professor of cardiology at UIC.

Although complications from standard catheterization through the groin are low, occurring in only 2 percent to 9 percent of patients, the transradial approach can reduce bleeding — the most common complication, particularly among women and the elderly — to under 1 percent. It also eliminates much of the discomfort associated with the procedure.

Following a standard angiogram and angioplasty through the femoral artery, the patient needs to lie still on his or her back for four to six hours. This can be very uncomfortable for elderly patients with back problems, Shroff said. Walking can be uncomfortable for days.

In contrast, patients who have the procedure done via the wrist can immediately sit up, eat, and walk without pain, said Shroff.

The transradial procedure has been widely adopted in Europe, where up to 60 percent of procedures are now done this way. In the U.S., only about 2 percent of coronary interventions use the procedure.

“The issue is really just the learning-curve,” said Shroff. “The change requires dozens of small changes — everything from redesigning the sterile drape so that the openings are at the wrist rather than the leg and finding smaller needles, wires and catheters to the way the table is set up.”

Last month, Shroff, Dr. Mladen Vidovich, UIC assistant professor of cardiology, and Bernadette Speiser, nurse manager in cardiology at the Jesse Brown VA Medical Center, led an all-day workshop at UIC in implementing a transradial approach that drew cardiologists and other catheter lab team members from the Chicago area and around the country. The Jesse Brown VA Medical Center is one of only a handful of VA centers in the country to offer the procedure.

“We’ve solved dozens of small problems that stand in the way of implementing this kind of program, so that everyone interested in transradial cardiac catheterization doesn’t have to re-invent the wheel,” said Speiser.

In addition to offering a ready-made approach to the technique, Shroff said the key is enlisting the help and cooperation of everyone involved in the cath lab, from nurses and nurse-managers to the technicians who set up the equipment.

Schroff says there is no downside to using the transradial approach where appropriate.

“And in these times, as everyone tries to think strategically about the delivery of healthcare, the savings in terms of costs and hospital resources offered by transradial catheterization make it especially attractive,” he said. “It is my belief that once a patient has their procedure done from the wrist, they will demand that approach in the future, if they require it again.

Vitamin D deficiency may contribute to a higher number of heart and stroke-related deaths among black Americans compared to whites, according to a University of Rochester Medical Center study.

The journal Annals of Family Medicine is publishing the study in the January-February edition, which goes online Jan. 11, 2010.

Researchers sought to understand the well-documented disparity between blacks and whites in cardiovascular deaths. They turned to vitamin D because growing evidence links low serum levels of D to many serious illnesses including diabetes, hypertension, kidney and heart disease.

Lead author Kevin Fiscella, M.D., said a complex host of genetic and lifestyle factors among blacks may explain why this population group has lower vitamin D levels across the lifespan than other races.

People get vitamin D through their diets, sun exposure, and oral supplements. Genetic factors common to blacks sometimes preclude vitamin D absorption, such as a higher incidence of lactose intolerance, which can eliminate vitamin-D fortified milk from the diet, and darker skin pigment that significantly reduces vitamin D synthesis.

“Therefore, our study suggests that the next step would be to intervene to boost vitamin D levels safely, with supplements,” said Fiscella, a national expert on disparities in health care and a professor of Family Medicine and Community and Preventive Medicine at URMC.

With funding through the National Heart Lung and Blood Institute, Fiscella and colleagues studied a sample of more than 15,000 American adults. The data included measurements of blood levels of vitamin D and death rates due to cardiovascular disease. Researchers also looked at other factors that contribute to heart health, such as body mass index, smoking status and levels of C-reactive protein.

Overall, the analysis showed that, as expected, a vitamin D deficiency was associated with higher rates of death among all people in the sample. In fact, those adults with the worst deficiency had a 40 percent higher risk of death from cardiac illness. This suggests that vitamin D may be a modifiable, independent risk factor for heart disease, Fiscella said.

Most striking, however, was that when researchers adjusted the statistics to look at race, blacks had a 38 percent higher risk of death than whites. As vitamin D levels rose, however, the risk of death was reduced. The same was true when researchers analyzed the effect of poverty on cardiovascular death rates among blacks, which suggests that vitamin D deficiency and poverty each exert separate risk factors, the study said.

A review article published in September 2009 in The American Journal of Medicine, noted that Vitamin D deficiency is a worldwide health problem. In the U.S., inadequate Vitamin D has been reported in about 36 percent of otherwise healthy young adults and about 57 percent of general medicine hospitalized patients.

Vitamin D is metabolized in the liver and converted to 25 hydroxyvitamin D or 25(OH) D, the form used to determine a person’s status through a blood test. Deficiency is usually defined by levels of less than 20 nanograms per milliliter; 30 ng/ml is viewed as sufficient. The mean blood level in the study sample was 29.5 ng/ml.

Most of the body’s tissues and cells have vitamin D receptors, making it a potent regulator of cell activity and growth. A deficiency contributes to inflammation associated with heart disease, many cancers and poor bone health.

Fiscella cautions, however, that not all observational studies of vitamin deficiency are borne out by subsequent clinical trials. For example, previous observational studies of vitamin E and beta-carotene that were associated with poor heart health did not hold up in later clinical studies. The need to further assess the vitamin D connection to heart disease is convincing, however, particularly among blacks, he added.

Other at-risk people include the obese and the elderly, (particularly housebound or nursing home residents), because vitamin D levels decline with age. And although more sun exposure can boost levels of D, skin cancer is also an increasing risk to many people. Therefore, medical authorities usually recommend increased dietary intake and/or supplementation as the best way to correct a deficiency.

US researchers investigating the disparity between blacks and whites in heart and stroke-related deaths have suggested that vitamin D deficiency may be partly responsible.

The National Heart Lung and Blood Institute funded study was led by Dr Kevin Fiscella of the University of Rochester Medical Center (URMC), New York, and is to appear in the January-February 2010 issue of the journal Annals of Family Medicine, which goes online on 11 January.

Fiscella is a national expert on disparities in health care and a professor of Family Medicine and Community and Preventive Medicine at URMC.

He and his colleagues decided to investigate vitamin D because there is growing evidence that low levels of the vitamin in the bloodstream is linked to diabetes, high blood pressure, kidney disease, heart disease, and other serious illnesses.

For the study, they looked at data on more than 15,000 American adults, including measurements of blood levels of vitamin D and death rates due to cardiovascular disease.

They also looked at other cardiovascular health factors such as BMI (body mass index), smoking status and levels of C-reactive protein (a measure of inflammation in the body).

Vitamin D gets into our bodies through diet, exposure to the sun and from supplements. The liver converts it to 25 hydroxyvitamin D or 25(OH) D, which is what is measured by a blood test.

Vitamin D deficiency is usually defined as having less than 20 nanograms per milliliter, with 30 ng/ml regarded as sufficient. The mean blood level among the participants in this study was 29.5 ng/ml.

The researchers also found that:

* Deficiency in vitamin D was linked to higher rates of death among all participants.

* Those most deficient in vitamin D had a 40 per cent higher risk of death from cardiac illness.

* Adjsuting for race showed that blacks had a 38 per cent higher risk of death than whites.

* However, this risk of death went down as vitamin D levels went up.

* Adjusting for poverty had a similar effect.

The authors said these findings suggest that vitamin D may be a modifiable, independent risk factor for heart disease, and that vitamin D and poverty exert separate effects.

Commenting on the disparity between blacks and whites, Fiscella said there was a complex host of genetic and lifestyle factors among blacks that might explain why they have lower vitamin D levels across the lifespan compared to other races.

Some black people have genetic factors that stop vitamin D being absorbed efficiently. One of these is higher lactose intolerance, which has an indirect effect in that people with this factor tend to exclude vitamin-enriched milk from their diet. Another is having darker skin pigment, which significantly reduces the amount of vitamin D made in the body.

Fiscella said that the findings suggest:

“The next step would be to intervene to boost vitamin D levels safely, with supplements.”

In September 2009, a review article in The American Journal of Medicine pointed out that vitamin D deficiency was a global health problem, occurring in about 36 per cent of otherwise healthy adult Americans and 57 per cent of general medicine hospitalized patients.

Most of the tissue and cells in our bodies have receptors for vitamin D: it plays a key role in controlling cell activity and growth. Deficiency in vitamin D helps cause inflammation associated with heart disease, cancer and bone illnesses.

Fiscella urged caution in interpreting these findings without a doing proper trial, however. This is an observational study and not a controlled clinical trial: some findings from observational studies don’t bear out in clinical trials, as certain studies on links between vitamin E and beta-carotene and poor heart health have shown.

However, Fiscella said the evidence here was convincing enough to warrant further investigation of the potential link between vitamin D and heart disease, particularly among blacks.

A vascular surgical technique pioneered at UT Southwestern Medical Center and designed to replace infected aortic grafts with the body’s own veins has proved more durable and less prone to new infection than similar procedures using synthetic and cadaver grafts.

Aortic graft infections are one of the most serious complications in patients undergoing aortic grafting procedures for peripheral arterial disease (PAD) and aortic aneurysms. PAD reduces blood circulation in the pelvis and lower extremities, and aortic aneurysms result in a weakening of the aortic wall that can cause lethal rupture of the aorta, the largest artery in the body. Patients with PAD and aortic aneurysms often require surgery, and aortic grafting procedures using synthetic grafts are typically the first line of treatment.

For patients with PAD, the procedure restores blood circulation to the legs, and for patients with aneurysm, it replaces the weakened aortic wall and prevents rupture. Synthetic grafts made of Dacron, a polyester material, are placed in the aorta and femoral arteries in the abdomen and groin, which feed blood to the legs. But in about 1 percent to 2 percent of these patients, the grafts become infected a complication that causes amputation and death if left untreated.

Dr. G. Patrick Clagett, chief of vascular surgery at UT Southwestern, pioneered a technique called the neo-aortoiliac system (NAIS) that repairs these aortic-graft infections. The procedure involves removing the infected graft and replacing it with sections of femoral-popliteal veins harvested from the patient’s thighs, rather than another synthetic graft or vessels harvested from human cadavers.

In a recent study published in the Journal of Vascular Surgery, Dr. Clagett and his team reported on 187 patients at UT Southwestern treated for aortic graft infections who underwent the NAIS procedure from 1990 to 2006. It is the largest group of such patients ever studied, and the researchers found that the incidence of re-infection was lower and the procedure resulted in superior durability with much lower long-term amputation rates when compared with other operations to treat this condition.

“This operation has gained favor worldwide in the treatment of this devastating condition,” said Dr. Clagett. “Since performing the first operation here in the 1990s, we have accumulated data over the years and have found this procedure to be far superior in overall patient outcomes.”

Simply replacing the old Dacron graft with a new synthetic graft can result in devastating infection of the new one, said Dr. Clagett, who is immediate past president of the Society for Vascular Surgery. His team and others also have found that the new synthetic or cadaver grafts tend to develop clots and new blockages.

“When we use the patient’s own tissue to construct a new graft, it provides an advantage because they are less likely to form clots within the graft and less likely to develop new blockages,” Dr. Clagett said. “Patients also need fewer subsequent procedures, a common problem with the other treatments for this complication.”

He added that patients who have the NAIS procedure don’t need to be on lifelong antibiotic therapy. Because the aortic reconstruction is fashioned with the patient’s own tissue, there is no foreign material that is prone to re-infection.

An international study authored by a UT Southwestern Medical Center researcher has concluded that the anemia drug darbepoetin alfa works no better than a placebo in several other applications previously thought to be promising.

Darbepoetin alfa is one of a class of drugs used to increase red blood cells in patients with type 2 diabetes, chronic kidney disease and anemia, but in a study of 4,038 patients, it did little to reduce cardiovascular problems, death or even the need for dialysis.

Patients have used the drug and other similar drugs for at least a decade to improve the symptoms of anemia.

“We were disappointed that the drug didn’t make a difference,” said Dr. Robert Toto, professor of internal medicine at UT Southwestern and senior author of the study in The New England Journal of Medicine. “We set out doing this trial to prove whether treatment of anemia would help our patients.”

Researchers also found that subjects who took the drug were nearly twice as likely to have a stroke as those who received a placebo – 101 subjects compared with 53.

“This is a surprise,” Dr. Toto said. “Clinicians should not expect that treatment of anemia with darbepoetin and other drugs in its class will reduce their risk of cardiovascular events or prevent their kidney disease from progressing. If a clinician is treating a patient for fatigue and other symptoms of anemia and the symptoms do not improve, they should consider stopping the drug, because it may expose the patient to increased risk of stroke.”

Chronic kidney disease, type 2 diabetes and anemia affect about 1 million people in the U.S., he said. Drugs such as darbepoetin alfa for treating anemic patients on dialysis (in the final stage of kidney disease) were approved in the late 1980s. Soon afterward, accepted guidelines suggested using the drug with chronic kidney disease patients not on dialysis in hopes of improving symptoms, cardiovascular death rates and preventing chronic kidney disease from progressing to dialysis.

While studies were done in an attempt to determine optimal hemoglobin levels using such drugs in these patients, no trial was conducted comparing the drug with a placebo, until TREAT ” Trial to Reduce Cardiovascular Events with Aranesp Therapy.

“From a scientific perspective, TREAT is the most rigorous,” Dr. Toto said. “It’s a randomized, double-blind, placebo-controlled trial.”