Promoting an increased awareness and standardized approaches in diagnosing and treating peripheral artery disease

PERIPHERAL ARTERY DISEASE (PAD)

Natural History of PAD

The course of PAD is notable for progressive atherothrombosis involving one or multiple arterial vascular beds (coronary, cerebrovascular, or lower extremity arteries). Thus, PAD patients have a heightened risk of ischemic cardiovascular, cerebrovascular, and limb events. The incidence of cardiovascular events is considerably higher than the morbidity and death from limb complications. The summary of clinical course of patients with PAD is shown in Figure 1 (6).

At 5 years following the diagnosis of PAD, 70-80% have stable claudication, 10-20% have worsening claudication and only a fraction require revascularization.

Critical limb ischemia (CLI), a severe manifestation of PAD, may be present at initial diagnosis of PAD in 1-2% of patients with PAD (7). CLI is associated with significant mortality and morbidity. As such, one year after the diagnosis of CLI, one in four patients may require amputation or die from cardiovascular causes (6). Besides, among patients who were asymptomatic, or had atypical symptoms or claudication at initial diagnosis of PAD, 1-2% may progress to CLI at 5 years (6). A recent analysis of the Medicare claims data reported 54% mortality and 3% major amputation at 4 years following the initial diagnosis of CLI (8).

Twenty percent of patients with PAD will have a myocardial infarction or stroke within 5 years after the diagnosis of PAD.  PAD is associated with an increased risk of death, mostly from cardiovascular causes; as such, the risk of death at 5 years is 15-30%, of which 75% are cardiovascular in origin (6, 9).

References

6.    Hirsch AT, Haskal ZJ, Hertzer NR, et al. ACC/AHA 2005 Practice guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Peripheral Arterial Disease): endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation. Circulation. 2006;113(11): e463-e654.

7.    Shishehbor MH, White CJ, Gray BH, et al. Critical Limb Ischemia: An Expert Statement. J Am Coll Cardiol. 2016 Nov 1;68(18):2002-2015.

8.    Mustapha JA, Katzen BT, Neville RF, et al. Disease Burden and Clinical Outcomes Following Initial Diagnosis of Critical Limb Ischemia in the Medicare Population. JACC Cardiovasc Interv. 2018;11(10):1011-1012.

9.    Criqui MH, Langer RD, Fronek A, et al. Mortality over a period of 10 years in patients with peripheral arterial disease. N Engl J Med. 1992; 326(6):381-386.