Studies probe diabetes vascular health
Vascular surgeon Mohamed Zayed, MD, PhD, is in the early stages of T1 translational research investigating the underlying mechanisms of atherosclerotic plaque progression in patients with diabetes and peripheral arterial disease (PAD). In this common and often difficult-to-treat patient group, blood flow in the lower legs and feet becomes severely restricted, leading to an inadequate blood supply to tissues. Zayed’s goal is to identify new drug therapies that can reduce serious complications such as wounds and limb amputations.
“Over the past decade, there has been significant progress in decreasing the rates of heart attacks and strokes in patients with diabetes; however, amputation rates remain stubbornly high,” says Zayed. “In fact, nearly 20 percent of diabetics who develop a peripheral limb wound will ultimately receive a major extremity amputation, which leads to further disability and represents a large socioeconomic burden.”
Patients with diabetes are more vulnerable to developing PAD than those without diabetes. Recent investigations suggest that the vulnerability may be due to a combination of accelerated atherosclerotic plaque formation in peripheral arteries, as well as an impaired ability to develop new, alternate blood vessels to compensate for existing arterial blockages.
Zayed works in collaboration with Clay Semenkovich, MD, the Herbert S. Gasser Professor and chief of the Division of Endocrinology, Metabolism and Lipid Research, to evaluate the role of specific fat molecules that may contribute to PAD severity in diabetic patients. Studying vascular tissue harvested from patients with and without diabetes, they are using mass spectrometry to analyze patients’ arterial plaques. In collaboration with Washington University’s Diabetes Research Center, they aim to identify plaque molecules that could be targeted with drugs delivered directly to the plaques. The clinical trial patients are enrolled in an institutionally approved vascular tissue biobank.
“Ultimately, our goal is to determine what lipid molecules correlate with diabetic PAD, and attempt to normalize them with novel drugs using existing minimally invasive surgical techniques.”
Zayed’s research is funded by the Society for Vascular Surgery Foundation, the Vascular Cures Foundation Wylie Scholar Award, the St. Louis Veterans Affairs Health Care System and the Washington University Diabetes Research Center.
Drug-coated balloons tested to treat PAD in the calf
The Section of Vascular Surgery, which has been a leader in endovascular surgery to treat peripheral arterial disease (PAD), is participating in the first clinical trial of drug (paclitaxel)-coated balloons in patients with decreased blood flow below the knee.
Drug-coated balloons have proven effective in preventing recurrent narrowing of the thigh arteries after angioplasty, and in this trial are now being tested in the smaller arteries of the calf. Successful treatment of blockages in these smaller arteries is critical in preventing amputation from PAD. Vascular surgeon Patrick Geraghty, MD, is one of three global principal investigators for the trial.
With the aging of the baby-boom generation, the increase in lower-extremity arterial disease has rivaled the occurrence of other vascular diseases such as carotid artery disease and abdominal aortic aneurysms. Endovascular treatment, with its decreased risk and faster recovery, is now widely used as an alternative to surgery in PAD.
Highlights
- At Barnes-Jewish Hospital, vascular surgeon Mohamed Zayed, MD, PhD, and interventional radiology colleagues are using a new FDA-approved percutaneous thrombectomy cannula to remove large-volume blood clots from the veins of the abdomen and pelvis. The cannula suctions and filters clots from the venous circulation while pumping back the remaining filtered venous blood to the patient.
- Professional and amateur athletes are among those seeking treatment from Robert Thompson, MD, for neurogenic, venous and arterial thoracic outlet syndrome (TOS). TOS involves nerve and/or blood vessel compression in the lower part of the neck, shoulder and upper arm. Among his patients are former major league pitcher Aaron Cook, Kansas City Royals pitcher Chris Young, who won Major League Baseball’s 2014 Comeback Player of the Year award, and roughly 18 other major league pitchers.
- Nanette Reed, MD, has joined Patrick Geraghty, MD, to extend the outreach of the vascular surgery section at Barnes-Jewish St. Peters Hospital, about 30 miles west of St. Louis. Both see patients and perform open and endovascular procedures.
- Vascular Surgery Residency and Fellowship Program Director Jeffrey Jim, MD, MPHS, has encouraged trainees to take on challenging, but practical safety/ quality-improvement projects. These include standardizing protocols for treating aortic dissections and emergent aneurysms, and developing new discharge instructions and preoperative protocols for common procedures.