UTHealth Researchers Study Device for Atrial Fibrillation at Memorial Hermann Heart & Vascular Institute

Newswise — HOUSTON – (Oct. 10, 2013) – A clinical trial evaluating a cardiac plug for the prevention of stroke in patients with atrial fibrillation has been launched by cardiology researchers at The University of Texas Health Science Center at Houston (UTHealth) Medical School.

In September, UTHealth cardiologists implanted the state’s first AMPLATZER™ Cardiac Plug (ACP) in a patient at the Memorial Hermann Heart & Vascular Institute-Texas Medical Center (HVI). The study will determine if the transcatheter device is safe and effective in preventing blood clots from migrating out of the left atrial appendage in patients with non-valvular atrial fibrillation who are at high risk for stroke.

“Atrial fibrillation is a common problem and patients need blood thinners to help prevent stroke,” said Pranav Loyalka, M.D., co-principal investigator of the Houston study, associate professor in the Program of Advanced Heart Failure at the UTHealth Medical School and associate chief of the medical division at the Center for Advanced Heart Failure at HVI. “AMPLATZER™ is one of the devices being studied that could give patients the ability to not take blood thinners.”

Atrial fibrillation is the most common type of arrhythmia, a problem with the rate or rhythm of the heartbeat caused by dysfunctional electrical activity. The heart can beat too fast, too slow or irregularly. It causes blood to pool in the atria, the heart’s upper two chambers, causing an inadequate supply of blood to pump into the ventricles, the lower chambers.

“When the blood pools in the atria, blood clots can form in the left atrial appendage, the site of 90 percent of blood clots associated with atrial fibrillation,” said Ramesh Hariharan, M.D., co-principal investigator and professor and medical director of the Complex Arrhythmia Center at the UTHealth Medical School and HVI.

An estimated 2.7 million Americans suffer from atrial fibrillation, which causes 20 percent of all ischemic strokes, the most common form of stroke. A person with atrial fibrillation is five times more likely to have a stroke.

“Symptoms of atrial fibrillation can include a racing heart and shortness of breath,” said Biswajit Kar, M.D., co-investigator, professor in the Program of Advanced Heart Failure at UTHealth and chief of the medical division at the Center for Advanced Heart Failure at HVI. “Over time, it can lead to heart failure.”

The most common blood thinners prescribed for atrial fibrillation are warfarin and dabigatran.

“The biggest drawback of warfarin is that patients need regular blood tests to check levels of the drug, which typically keep changing, causing cardiologists to adjust the dosage to prevent dangerous bleeding,” said Richard Smalling, M.D., co-investigator, professor and the Jay Brent Sterling Professor of Cardiovascular Medicine and James D. Woods Distinguished Chair of Cardiovascular Medicine at the UTHealth Medical School and interventional cardiologist at HVI.

“Dabigatran remains at more consistent levels in the body but there is no reversal agent for it, so if a person is in an automobile or other accident, there is a risk for excessive bleeding,” said Saumya Sharma, M.D., co-investigator, assistant professor in the Complex Arrhythmia Center at UTHealth and cardiologist at HVI.

The AMPLATZER™ plug is a self-expanding device made from nitinol mesh to seal the left atrial appendage, minimizing the chance of blood clots migrating into bloodstream. Patients usually have a one-night hospital stay.

“It’s like a windsock,” Loyalka said. “It plugs it so that nothing can get through and we believe this can help prevent stroke.”

The multiple-site study will enroll between 400 and 3,000 patients. It is randomized with two patients receiving the device and one patient receiving traditional medical treatment using long-term, blood-thinning medication. For more information, call the Center for Advanced Heart Failure at Memorial Hermann Heart & Vascular Institute-Texas Medical Center at (713) 704-4300.

Study Finds Racial and Social Disparities in Kidney Allocation Among Young Transplant Recipients

 

• Among kidney transplant recipients younger than 40 years of age, African Americans and individuals with less education were more likely to receive lower-quality organs than Caucasians and those with college degrees.
• African Americans with higher education levels were not more likely to receive a lower-quality kidney than Caucasians with college degrees.

Newswise — Washington, — Among younger kidney transplant recipients, a disproportionate number of African Americans and individuals with less education receive organs that are of lower quality or are considered marginal, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN). The findings suggest that there are racial and social disparities in the allocation of transplanted organs that need to be addressed.

Older kidney disease patients who have a high risk of dying while on dialysis may benefit from accepting a so-called extended criteria donor (ECD) kidney—which is more likely to fail than a standard criteria donor kidney—rather than remaining on a transplant wait list. But younger patients and those with short wait times are usually better off holding out for a standard criteria donor kidney. Despite this, some young patients still end up receiving ECD kidneys.

Rajesh Mohandas MD, MPH, Mark Segal MD, PhD (University of Florida), and their colleagues looked to see if demographic factors play a role in whether younger patients accept ECD kidneys. They analyzed all first single-kidney transplants documented in the United States from 2000 to 2009 in patients 18 to 40 years of age and waitlisted less than three years.

Among the major findings:
• Of 13,615 ECD transplants, 591 (4.3%) kidneys went to recipients between 18 and 40 years of age who were waitlisted less than three years.
• African Americans were 1.7 times more likely to receive an ECD kidney than Caucasians.
• Individuals with less education were 2.3 times more likely to receive an ECD kidney than those with a college degree; however, African Americans with higher education levels were not more likely to receive such a lower-quality kidney than Caucasians with college degrees.

“To our knowledge, this is the first report showing that there are racial and social disparities in the quality of allocated transplanted organs. Understanding that such disparities exist is the essential first step to addressing inequalities in health care and to attempt to improve patient outcomes,” said Dr. Mohandas. He added that it is important to ensure that kidney transplant candidates are not just informed, but also educated about their choices.

Study co-authors include Michael Casey, MD, Robert Cook, MD, MPH, Kenneth Lamb, PhD, and Xuerong Wen, MS.

Disclosures: The authors reported no financial disclosures.

The article, entitled “Racial and Socioeconomic Disparities in the Allocation of Extended Criteria Donor Kidneys,” will appear online at http://cjasn.asnjournals.org/ on October 10, 2013, doi: 10.2215/CJN01430213.

The content of this article does not reflect the views or opinions of The American Society of Nephrology (ASN). Responsibility for the information and views expressed therein lies entirely with the author(s). ASN does not offer medical advice. All content in ASN publications is for informational purposes only, and is not intended to cover all possible uses, directions, precautions, drug interactions, or adverse effects. This content should not be used during a medical emergency or for the diagnosis or treatment of any medical condition. Please consult your doctor or other qualified health care provider if you have any questions about a medical condition, or before taking any drug, changing your diet or commencing or discontinuing any course of treatment. Do not ignore or delay obtaining professional medical advice because of information accessed through ASN. Call 911 or your doctor for all medical emergencies.

Founded in 1966, and with more than 14,000 members, the American Society of Nephrology (ASN) leads the fight against kidney disease by educating health professionals, sharing new knowledge, advancing research, and advocating the highest quality care for patients.

Recently published research by the founder of ClinMet and UC San Diego team demonstrates value of metabolomics based on urine to translational medicine

 

SAN DIEGO, Oct.11, 2013 - ClinMet announced today that researchers of the University of California, San Diego School of Medicine have published new research of metabolomics that uncovers a novel, feature and very consistent biochemical signature in urine associated with diabetic kidney disease. The results, which form a basis of the proprietary clinical metabolomics of ClinMet platform, have implications for the identification of biomarkers clinically useful for kidney function and to sharpen the development of drugs and clinical trials related to chronic kidney disease, as well as diabetes, obesity and cardiovascular disease.

The new research, authored by U.C. San Diego Professor and founder scientific ClinMet, Kumar Sharma, M.D., F.A.H.A (Director of the Center for translational medicine Renal Division of Nefrologia-hipertension and the Institute of Medicine of the metabolomics) and his colleagues, appears online in the journal of the American Society of Nephrology. ClinMet has an exclusive license to use this set of metabolites in the development of drugs and other applications, based on patents requested by UC San Diego.

The researchers quantified 94 metabolites in the urine in patients with diabetes (type 1 or type 2) and chronic kidney disease (CKD), subjects with diabetes but no kidney disease and healthy controls. They found that 13 of the metabolites were significantly different in people with disease compared with healthy controls (p-values between 10-3 to 10-18), and 12 of 13 was still highly significant in comparison with patients with type 1 or type 2 and not CKD. In addition, 12 of the 13 metabolites were linked to Mitochondrial Metabolism and suggested global suppression of mitochondrial activity in subjects with chronic kidney diseases in relation to healthy individuals. This conclusion is in sharp contrast to prevailing beliefs about excess activity mitochondrial having a causal relationship with diabetic complications. The conclusions based on urine metabolomics studies were independently validated based on protein and DNA analysis, indicating reduced mitochondrial contents in the kidneys of patients with diabetic nephropathy.

"It is evident from this study that urine and plasma-based metabolomics can be a rich source of biomarkers to understand and treat kidney disease diabetes and possibly related to cardiovascular complications," said Dr. Sharma. "This approach also offers direct insights into the biochemical pathways associated with kidney dysfunction".

Power of clinical metabolomics

"Genomics can help to predict the overall risk of disease or potential response of a patient to a drug, but you can not capture the effects that changes in diet, environmental factors or other diseases in the progression of the disease or improvement," said Yesh Subramanian, President, CEO and co-founder of ClinMet. "Clinical metabolomics, by contrast, allows us to quickly see biochemically what happens in the specific pathways of the disease over time and in the context of other factors that affect the health of the patient, including drug therapy. This makes clinical metabolomics a highly useful platform for research and translational drug development".

"We see clinical metabolomics allowing pharmaceutical and biotech clients to effectively apply the medicine precision today", said Mr. Subramanian. "The ability to predict which patients are likely to respond better to specific treatments holds immense promise for sharpening of phase 2 and 3 clinical trials now and improve the clinical medicine in the future".

About ClinMet (clinical metabolomics Inc.)

ClinMet, founded in 2011, is a privately held company headquartered in San Diego, CA that provides pharmaceutical companies with clinically relevant insights and useful data on the effectiveness of the medication, safety and mechanism of action using its proprietary platform urine biomarker metabolomics for diabetes, kidney disease, obesity, and cardiovascular disease. ClinMet applies its unique combination of clinical expertise, in-depth proprietary metabolomics experience and computer skills to improve the rate of speed and the success of drug development. The company helps drug developers efficiently transform compounds promising safe and effective medicines and to effectively develop and implement its strategy of companion Diagnostics.

ClinMet technology and clinical experience is based on the legacy of research of William Nyhan, M.D., Ph.d., founder of head of the biochemical genetics and laboratory of metabolomics and founding Chair of the Department of Pediatrics at UC San Diego. Dr. Nyhan, one of the founders of the field of metabolic diseases human and his team have developed many methods of diagnosis standard of gold of the mass spectrometry and analysis metabolomic which are used by the centres of excellence in human genetics and metabolism around the world. On the other hand, cientifico-fundador ClinMet, Kumar Sharma, is an expert recognized worldwide in diabetic nephropathy and translational research. He has conducted several studies milestone in diabetic nephropathy in a level of translational research and has dedicated his career to develop new therapies for patients with chronic kidney disease.