Peripheral arterial disease affects 15–20 million Americans, but it is not being properly diagnosed or treated, according to the authors of new guidelines for the management of PAD.
“Severe peripheral arterial disease is essentially an overlooked medical emergency in the United States,” said Dr. Alan T. Hirsch, chairman of the guidelines writing committee, in a briefing with reporters.
Cochair Dr. Ziv J. Haskal said a lack of focus on PAD—both by patients and physicians—has led to an average 4-month delay in diagnosing critical limb ischemia. Up to 80% of amputations may be due to that condition, and 60% may be preventable by earlier interventions, said Dr. Haskal, director of the vascular and interventional radiology division at New York-Presbyterian Hospital/Columbia University Medical Center in New York.
Though the panel cochairs emphasized that PAD is underdiagnosed and undertreated, they hesitated to point fingers.
“This isn't about looking back with blame. This is about looking forward,” Dr. Hirsch said.
The committee called on physicians to routinely ask patients if they have PAD symptoms, and to adopt physical exam techniques to ferret out blockages in the legs, feet, aorta, kidneys, and intestines.
Guidelines on PAD have been published before, but none have had such broad backing, noted Dr. Hirsch, who is director of Abbott Northwestern Hospital's Vascular Center in Minneapolis.
The American Heart Association/ American College of Cardiology Guidelines for the Management of Patients With Peripheral Arterial Disease is a product of the American Association for Vascular Surgery/Society for Vascular Surgery, the Society for Cardiovascular Angiography and Interventions, the Society of Interventional Radiology, the Society for Vascular Medicine and Biology, and the ACC/AHA Task Force on Practice Guidelines. They were endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; the National Heart, Lung, and Blood Institute; the Society for Vascular Nursing; the TransAtlantic Inter-Society Consensus; and the Vascular Disease Foundation.
The 17-member committee, which included representatives of most of these organizations, pored over 1,300 peer-reviewed studies to provide what Dr. Hirsch called “very powerful, evidence-based tools.”
The guidelines cover the diagnosis and management of atherosclerotic, aneurysmal, and thromboembolic PAD, but are limited to the abdominal aorta and its branches, the kidneys, the intestines, the legs, and the feet. Separate guidelines will be issued by the ACC in the spring on extracranial and vertebral arteries.
The guidelines offer background on each condition, including causes, risk factors, prevalence, and how to recognize it. Diagnosis and treatment recommendations are given, along with a corresponding rating of the level of evidence that supports the test or therapy.
Primary care physicians need to take on more responsibility for identifying PAD, the guidelines committee said.
“The key to this is it requires awareness among primary care physicians,” said Dr. Norman R. Hertzer, a cochair and chairman emeritus of the department of vascular surgery at the Cleveland Clinic.
For lower-extremity PAD, diagnosis can be confirmed with an ankle brachial index, which should be done for individuals at high risk for blockages in the legs or suspected of having such blockages.
Dr. Hirsch said that this recommendation would require a change in clinical practice, but that it “is important even for those with negligible to no symptoms because it represents a powerful opportunity” to prevent stroke, gangrene, amputation, or death. The guidelines have a table identifying patients who should have an ankle brachial index performed.
Dr. Haskal noted that PAD in the kidneys can lead to loss of function or difficult-to-control hypertension, which can affect heart function. Primary care physicians should consult the guidelines' algorithms on identifying who is at risk and who should be screened, he said. Screening is done largely with proven noninvasive imaging techniques such as duplex ultrasound.
Dr. Hertzer said screening is also crucial to identifying abdominal aortic aneurysms before they rupture. The mortality rate from a ruptured aneurysm—50%—has remained unchanged for decades, he said. But the risk of death after an elective repair is only 5%.
“A routine physical exam should not just involve listening to the chest and taking a chest x-ray. It should also include an abdominal exam in the office, and we've emphasized that in the guidelines,” Dr. Hertzer said.
The guidelines give recommendations on exam techniques and on treatment options, including a comparison of open abdominal repair vs. endograft repair. The endograft appeals to patients and poses a lower operative risk in sicker patients, but it has a higher rate of late complications and requires lifelong surveillance with CT scans to determine the stability of the graft and an absence of leaks, he said.