PAD and diabetes: Vascular testing could save limbs, especially for black patients

A 72-year-old black woman with diabetes, hypertension, dyslipidemia and peripheral arterial disease presented with a 3-month history of a non-healing ulceration on the plantar surface of her left fourth metatarsal. Her podiatrist referred her to me for vascular evaluation.

Robert S. Dieter

Angiography saves limbs

My patient’s condition is not uncommon. PAD affects over 10 million Americans. It is twice as common in blacks as in non-Hispanic whites.

Unfortunately, when PAD presents in its most advanced form — critical limb ischemia (CLI) — nearly 10% of patients will undergo an amputation within 3 months of diagnosis. The number climbs to 40% by 6 months. At 1 year, only about half are alive with their limb intact. One-year mortality for these patients is alarmingly high, at just under 25%.

My patient was fortunate. She got to us in time, and we were proactive with vascular testing and ultimately revascularization. Her leg was saved. We were able to improve her quality of life and begin proactively evaluating her overall CV health, because we know that where there is PAD, there is likely CAD. As it is for so many patients, PAD was simply the tip of the iceberg and she required aggressive secondary CV prevention.

This strategy of proactive vascular testing is not routine before amputation. In an analysis of lower extremity vascular testing prior to amputation in Medicare patients between 2000 and 2010, Vemulapalli and colleagues demonstrated that only 68.4% of amputees had undergone some type of vascular testing in the 12 months leading up to an amputation. Too many are not considered for revascularization simply because the patient was never evaluated for PAD.

Fig. 1

The most recent Dartmouth Atlas of Health Care release, “Variation in the Care of Surgical Conditions: Diabetes and Peripheral Arterial Disease,” highlighted significant racial and geographic disparities in patients undergoing amputations for CLI. They evaluated the rates of amputation in Medicare beneficiaries with diabetes and PAD and found that average ranges for amputation varied significantly by region (Table) and for black vs. non-black patients.

Every 30 seconds a lower extremity is lost due to diabetes alone. As a country, the United States spends between $10 billion and $20 billion every year on the care of amputees. By not proactively identifying those at risk and considering revascularization as a possible treatment option, we are allowing too many patients to suffer unnecessary amputation.

Fig. 2

Clearly, much more emphasis must be placed on the diagnosis and treatment of CLI and on eliminating racial disparities. This should be a priority for clinicians and our professional societies. It is our duty as CV specialists to help identify and treat these patients and raise the standard of care not only across America, but also across the world.

Patient treatment, outcome

Here’s how I evaluated and treated my patient: First, I performed noninvasive vascular testing, including an ankle-brachial index (ABI) test and found her right ABI was 0.79, and left ABI was 0.48. We moved on to angiography, which revealed occlusion of the left tibioperoneal trunk (Figure 1) and then to angioplasty (Figure 2). The procedure resulted in restoration of three-vessel flow to her foot (Figure 3). Her ABI improved to 0.91.

Fig. 3

After 2 months of continued wound care with her podiatrist, the ulceration completely healed. Preservation of her limb allowed her to continue to lead an active lifestyle

So, how would have you seen patients like this treated at your hospital? Are they referred to you for CV care post amputation? Surgical clearance pre-operatively?

How would you proceed and how do you think other healthcare providers would typically proceed?

Would this patient be referred for amputation? Or could her limb be saved?

Why should the answers to these questions depend on where in the United States the patient was being treated?

Robert S. Dieter, MD, RVT, FSCAI, is an associate professor of medicine at Loyola University, Chicago, and is a Cardiology Today’s Intervention Editorial Board member. He is passionate about the multidisciplinary treatment and advancement of vascular disease.

Figure Legends:

Figure 1. Baseline angiogram of a 72-year-old black woman with a history of CVD, and a 3-month non-healing ulceration on the plantar surface of her left fourth metatarsal.

Figure 2. Angioplasty was performed.

Figure 3. Post-angioplasty angiogram revealed restoration of three-vessel flow to the patient’s foot. The patient’s ABI improved to 0.91.

References:

Dieter RS. Peripheral Arterial Disease. McGraw-Hill; 2009.

Dartmouth Institute. “Variation in the Care of Surgical Conditions: Diabetes and Peripheral Arterial Disease. A Dartmouth Atlas of Health Care Series.” 2014. Available at: http://www.dartmouthatlas.org/downloads/reports/Diabetes_report_10_14_14.pdf

Vemulapalli S. Circ Cardiovasc Qual Outcomes. 2014;doi:10.1161/circoutcomes.113.000376.

Disclosure: Dieter reports no relevant financial disclosures.