Trends in Treating Lower Extremity PAD Studied
July 1, 2009—The Society for Vascular Surgery announced that Philip P. Goodney, MD, et al have published a study in the Journal of Vascular Surgery, assessing national trends in comparative treatments for lower extremity peripheral arterial disease (PAD) (2009;50:54–60).
The investigators found that endovascular interventions are now performed much more commonly than bypass surgery when treating lower extremity PAD. They noted that these changes far exceed simple substitution; in fact, more than three additional endovascular interventions were performed for every one procedure declined in lower extremity bypass surgery. During this same time period, major lower extremity amputation rates have fallen by more than 25%. However, further study is needed before any causal link can be established between lower extremity vascular procedures and improved rates of limb salvage in patients with PAD, the investigators concluded.
According to the investigators, advances in endovascular interventions have expanded the options that are available for the invasive treatment of lower extremity PAD. Whether endovascular interventions substitute for conventional bypass surgery or they are simply additive has not been investigated, and their effect on amputation rates is unknown. Therefore, the investigators sought to analyze trends in lower extremity endovascular interventions (angioplasty and atherectomy), lower extremity bypass surgery, and major amputation (above and below the knee) in 100% samples of Medicare Part B beneficiaries between 1996 and 2006. Using physician specialty identifiers, the investigators also examined trends in the specialty performing the primary procedure.
As detailed in the Journal of Vascular Surgery, from 1996 to 2006, the rate of major lower extremity amputation declined significantly (263 to 188 per 100,000; risk ratio [RR] 0.71; 95% confidence interval [CI], 0.6–0.8). Endovascular interventions increased more than threefold (from 138 to 455 per 100,000; RR = 3.3; 95% CI, 2.9–3.7), whereas bypass surgery decreased by 42% (219 to 126 per 100,000; RR = 0.58; 95% CI, 0.5–0.7). The increase in endovascular interventions consisted both of a growth in peripheral angioplasty (from 135 to 337 procedures per 100,000; RR = 2.49; 95% CI, 2.2–2.8) and the advent of percutaneous atherectomy (from 3 to 118 per 100,000; RR = 43.12; 95% CI, 34.8–52). Investigators noted that percutaneous atherectomy is a particularly new, expensive, and relatively untested treatment; however, its rate of use has increased by more than 4,100%. In 1996, radiologists performed the majority of endovascular interventions, but by 2006, more than 80% of interventions were performed by cardiologists and vascular surgeons. Overall, the total number of all lower extremity vascular procedures nearly doubled during the decade (from 357 to 581 per 100,000; RR = 1.63; 95% CI, 1.5–1.8), reported the investigators.
"We suspect new procedures may have translated into better outcomes, given the significant decline in amputation rates," commented Dr. Goodney. "However, other aspects of healthcare provided to patients at risk for amputation have changed along with the rates of surgical and endovascular procedures. Medicare patients are much more likely to receive medical and podiatric care, such as cholesterol monitoring, diabetic foot examinations, and blood glucose monitoring, which are aimed more toward preventing amputation now than they were 10 years ago. Our future work aims to determine if amputation rates are falling because of better medical care, changes in revascularization strategies, or a combination of the two."
Dr. Goodney stated that larger and broader clinical trials should compare bypass and endovascular interventions in patients with claudication and critical limb ischemia to further evaluate what medical steps can be taken and what resources should be used to obtain the best functional outcomes in patients with PAD and to prevent death and disability from lower extremity amputation.