Print this page
Inflammatory Marker May Indicate Postoperative Vascular Events
Lower extremity vein graft bypass patients with elevated C-reactive protein more at risk
CHICAGO (January 02, 2007) —
High levels of high sensitivity C-reactive protein (hsCRP), an inflammatory marker, are associated with an increased risk for major cardiovascular (CV) and graft-related events in patients following lower extremity vein bypass (LEB) surgery. This research, from Brigham and Women’s Hospital and the Beth Israel Deaconess Medical Center, both in Boston, Mass., was published in the January 2007 issue of the Journal of Vascular Surgery.
In this first study of its kind, the investigators examined the relationship between systemic inflammation and surgical bypass outcomes in 91 patients who underwent LEB using autogenous vein grafts. A baseline plasma sample was obtained the morning of surgery that included biomarkers for inflammation: hsCRP, fibrinogen and serum amyloid A. All three inflammatory markers were higher in patients who had critical limb ischemia (CLI) at initial presentation. During follow-up (mean 342 days), which included duplex ultrasound graft surveillance, there were 41 adverse events including four deaths, 27 graft-related events and 10 other CV events. Among the patients who had an elevated hsCRP (>5 mg/L) just prior to surgery, major postoperative vascular events occurred in 60 percent over the follow-up period, compared to 32 percent in those with baseline hsCRP
< 5 mg/L.
Michael S. Conte, MD, from the division of vascular and endovascular surgery at Brigham and Women’s Hospital, said elevated hsCRP was a strong indicator for cardiovascular events in this surgical cohort of patients with advanced peripheral arterial disease (PAD). “CRP has also been linked to PAD progression and severity of functional impairment,” said Dr. Conte. He added that hsCRP appeared to be associated specifically with vein graft-related events that included surgical revision, percutaneous re-intervention, graft occlusion or amputation of the index leg over the subsequent year. This may suggest a causal relationship between inflammation and vein graft failure.
“Peripheral arterial disease affects up to 1 in 10 people over 60 years old,” said Dr. Conte, “however it is largely under-recognized, under-diagnosed and under-treated by physicians. It may be the initial manifestation of cardiovascular disease in some patients, and mortality in the PAD population equals or exceeds that of patients whose initial sign is an isolated heart attack or stroke. Greater awareness of PAD will lead to the saving of both lives and limbs.”
Most patients can be treated with lifestyle changes (smoking cessation, weight loss, more exercise), aspirin and cholesterol-lowering drugs to decrease cardiovascular risk factors. However, in some cases, PAD causes pain which cause patients to experience limited ability to walk, pain at rest, gangrene or ulcerations that do not heal. For those most at risk for amputation, bypass surgery with a vein taken from the patient’s own leg or arm offers the most durable long-term treatment.
“Even though bypass surgery using vein is currently the best treatment for many patients with severe PAD, there is a 30 to 50 percent chance that within five years, the bypass graft will either completely close or narrow; in such cases another procedure, such as a balloon treatment or surgery, is then needed to keep it open,” said Dr. Conte. “Surgeons are currently unable to reliably predict which patients will develop narrowing of grafts over time, so all patients must be closely followed.”
Dr. Conte noted that hsCRP levels >3 mg/L have been associated with development of heart disease in patients without any other known risk factors. The American Heart Association (AHA) has three CRP risk categories for cardiovascular events: low, 0-1 mg/L, intermediate, 1-3 mg/L and high, >3 mg/L. The Association also recommends testing for high sensitivity CRP in patients at intermediate risk for development of heart disease, regardless of other traditional risk factors. In this study, the median hsCRP level in patients undergoing leg bypass surgery was 3.2 mg/L, placing this surgical population squarely within the highest risk AHA category.
In this first study of its kind, the investigators examined the relationship between systemic inflammation and surgical bypass outcomes in 91 patients who underwent LEB using autogenous vein grafts. A baseline plasma sample was obtained the morning of surgery that included biomarkers for inflammation: hsCRP, fibrinogen and serum amyloid A. All three inflammatory markers were higher in patients who had critical limb ischemia (CLI) at initial presentation. During follow-up (mean 342 days), which included duplex ultrasound graft surveillance, there were 41 adverse events including four deaths, 27 graft-related events and 10 other CV events. Among the patients who had an elevated hsCRP (>5 mg/L) just prior to surgery, major postoperative vascular events occurred in 60 percent over the follow-up period, compared to 32 percent in those with baseline hsCRP
< 5 mg/L.
Michael S. Conte, MD, from the division of vascular and endovascular surgery at Brigham and Women’s Hospital, said elevated hsCRP was a strong indicator for cardiovascular events in this surgical cohort of patients with advanced peripheral arterial disease (PAD). “CRP has also been linked to PAD progression and severity of functional impairment,” said Dr. Conte. He added that hsCRP appeared to be associated specifically with vein graft-related events that included surgical revision, percutaneous re-intervention, graft occlusion or amputation of the index leg over the subsequent year. This may suggest a causal relationship between inflammation and vein graft failure.
“Peripheral arterial disease affects up to 1 in 10 people over 60 years old,” said Dr. Conte, “however it is largely under-recognized, under-diagnosed and under-treated by physicians. It may be the initial manifestation of cardiovascular disease in some patients, and mortality in the PAD population equals or exceeds that of patients whose initial sign is an isolated heart attack or stroke. Greater awareness of PAD will lead to the saving of both lives and limbs.”
Most patients can be treated with lifestyle changes (smoking cessation, weight loss, more exercise), aspirin and cholesterol-lowering drugs to decrease cardiovascular risk factors. However, in some cases, PAD causes pain which cause patients to experience limited ability to walk, pain at rest, gangrene or ulcerations that do not heal. For those most at risk for amputation, bypass surgery with a vein taken from the patient’s own leg or arm offers the most durable long-term treatment.
“Even though bypass surgery using vein is currently the best treatment for many patients with severe PAD, there is a 30 to 50 percent chance that within five years, the bypass graft will either completely close or narrow; in such cases another procedure, such as a balloon treatment or surgery, is then needed to keep it open,” said Dr. Conte. “Surgeons are currently unable to reliably predict which patients will develop narrowing of grafts over time, so all patients must be closely followed.”
Dr. Conte noted that hsCRP levels >3 mg/L have been associated with development of heart disease in patients without any other known risk factors. The American Heart Association (AHA) has three CRP risk categories for cardiovascular events: low, 0-1 mg/L, intermediate, 1-3 mg/L and high, >3 mg/L. The Association also recommends testing for high sensitivity CRP in patients at intermediate risk for development of heart disease, regardless of other traditional risk factors. In this study, the median hsCRP level in patients undergoing leg bypass surgery was 3.2 mg/L, placing this surgical population squarely within the highest risk AHA category.
About Journal of Vascular Surgery
Journal of Vascular Surgery provides vascular, cardiothoracic and general surgeons with the most recent information in vascular surgery. Original, peer-reviewed articles cover clinical and experimental studies, noninvasive diagnostic techniques, processes and vascular substitutes, microvascular surgical techniques, angiography and endovascular management. Special issues publish papers presented at the annual meeting of the Journal's sponsoring society, the Society for Vascular Surgery. Visit the Journal Web site.
About the Society for Vascular Surgery
The Society for Vascular Surgery (SVS) is a not-for-profit medical society that seeks to advance excellence and innovation in vascular health through education, advocacy, research and public awareness. SVS is the national advocate for 2,400 vascular surgeons dedicated to the prevention and cure of vascular disease.
###
Society for Vascular Surgery - 633 N. St. Clair, 24th Floor; Chicago, IL 60611; Phone: 312-334-2300 or 800-258-7188; Fax: 312-334-2320; Email: vascular@vascularsociety.org
© 2008 VascularWeb. All rights reserved. Use of the VascularWeb site constitutes acceptance of all of the policies, rules and regulations for the site.
© 2008 VascularWeb. All rights reserved. Use of the VascularWeb site constitutes acceptance of all of the policies, rules and regulations for the site.