Peripheral circulation disorders are diseases affecting the circulatory system outside of the heart and brain. These conditions impact the body’s ability to deliver oxygenated blood or return deoxygenated blood, often affecting the limbs. Terminology, particularly the distinction between Peripheral Vascular Disease (PVD) and Peripheral Artery Disease (PAD), is a significant source of confusion. While these two terms are often encountered, they do not describe the exact same condition.
Clarifying the Relationship Between PVD and PAD
Peripheral Vascular Disease (PVD) is the comprehensive term describing any condition affecting blood vessels outside of the heart and brain. This broad category includes diseases of the arteries, veins, and lymphatic vessels. Examples falling under the PVD umbrella include Deep Vein Thrombosis (DVT), which involves blood clots in the veins, and chronic venous insufficiency, which impairs vein valve function.
Peripheral Artery Disease (PAD) is a specific type of PVD that affects only the arteries. PAD is characterized by the narrowing or blockage of these vessels, most commonly in the legs, which carry oxygen-rich blood away from the heart. The distinction lies in the vessel type: PVD covers all peripheral vessels, while PAD is exclusively about peripheral arteries.
The frequent confusion arises because PVD and PAD are often used interchangeably in current medical practice, especially in the United States, when referring to arterial issues caused by plaque buildup. Since arterial narrowing (PAD) is the most common and clinically significant form of peripheral vascular disease, the broader term PVD often serves as a synonym for PAD. Understanding this nuance is important because a problem with a vein, which is PVD, requires a different approach than an artery problem (PAD).
Primary Mechanism of Peripheral Artery Disease
The root cause for the majority of Peripheral Artery Disease cases is atherosclerosis, a progressive condition often called “hardening of the arteries.” This process begins when fatty deposits, cholesterol, calcium, and other cellular waste products accumulate on the inner lining of the artery wall, forming plaque. This plaque buildup stiffens the arteries and reduces their interior diameter, restricting blood flow.
This narrowing, known as stenosis, limits the oxygen and nutrients delivered to tissues and muscles, particularly in the lower extremities. Certain risk factors accelerate arterial plaque formation. Smoking is the most significant preventable risk factor, dramatically increasing the chances of PAD development and progression. Uncontrolled diabetes, high blood pressure (hypertension), and high cholesterol (hypercholesterolemia) also contribute to arterial wall damage and inflammation, promoting plaque growth.
Recognizable Signs and Symptoms
The reduction in blood flow caused by arterial narrowing manifests as physical signs and symptoms, primarily in the legs and feet. The most characteristic symptom of PAD is intermittent claudication, defined as muscle pain, cramping, or fatigue in the legs. This pain is predictably triggered by physical activity and quickly relieved by rest. The location of the discomfort often indicates where the artery is narrowed, commonly affecting the calf muscles, but sometimes the thigh or buttocks.
As the disease progresses and blood flow restriction worsens, symptoms can occur even at rest. Patients may experience burning or aching pain in the feet or toes, especially when lying flat at night. Other visible signs relate to poor tissue nourishment, including hair loss on the legs and feet, slow-growing or thickened toenails, and shiny, thin, or cool skin. A serious sign of advanced PAD is the formation of sores or ulcers on the legs or feet that do not heal due to inadequate blood supply.
Management and Lifestyle Interventions
Management of Peripheral Artery Disease centers on preventing atherosclerosis progression and alleviating symptoms to improve quality of life. The most impactful intervention is the complete cessation of smoking, which slows disease advancement. Even minimal tobacco use severely constricts blood vessels and harms the arterial lining.
Controlled exercise is a cornerstone of management, specifically supervised walking programs that improve walking distance and reduce pain. Although initially uncomfortable due to claudication, this therapy helps the body develop collateral circulation (new small blood vessels) to bypass blockages. Managing underlying systemic conditions through diet and medication is also important, including lowering blood pressure and aggressively controlling blood sugar levels in people with diabetes. Pharmacological treatments often include antiplatelet medications, such as aspirin or clopidogrel, to reduce the risk of blood clots forming in the narrowed arteries. Most patients are also prescribed a high-intensity statin medication to lower cholesterol, stabilize plaque, and reduce the risk of heart attack or stroke.