Kardiovaskulárny systém

Arterial circulation delivers oxygenated blood and essential nutrients to organs and tissues throughout the body. The distribution of blood volume required for various physiological functions is regulated by altering the diameter of arteries. This process involves vasodilation (widening of arteries) or vasoconstriction (narrowing of arteries), which helps control blood flow to different tissues and organs based on their needs. 

The distribution of blood through the vessels varies among different tissues and organs, depending on their metabolic needs and physiological functions. The blood flow in the myocardial circulation through the coronary arteries can increase to a volume 3–4 times higher than that of the resting state. The heart muscle is responsive to a diminished oxygen supply, a condition that can result from the narrowing of coronary arteries or insufficient blood delivery. 

During physical activity, blood circulation to working muscles can increase significantly, reaching 50–75 mL/100 g (10–15 times the resting flow of 4–7 mL/100 g), depending on the activity level. Consequently, a decrease in blood supply to the muscles, such as from narrowing peripheral arteries, tends to manifest symptoms primarily during physical activity. The red, oxidative-type muscle fibers primarily generate energy (ATP) through aerobic processes involving oxygen and are particularly sensitive. This sensitivity allows them to sustain continuous work efficiently. 

Obliterative peripheral arterial disease can be caused by factors such as atherosclerosis (arteriosclerosis), inflammation, or damage to the blood vessels.

In the initial phase of atherosclerosis, damage to the vascular wall's intima (inner layer) occurs, leading to the deposition of intracellular fat. Even though the lesion is present in the early stages of atherosclerosis, the degree of stenosis (narrowing) is negligible, and individuals may not experience symptoms at this point. During the second and third decades of life, extracellular fat accumulates, leading to the development and increasing significance of atheroma. Symptoms emerge based on the degree of occlusion, typically in response to increased muscle strain. In the fourth decade of life, a fibrous 'cap' forms around the atheroma, creating a 'plaque,' and calcium deposition initiates within the plaque. The degree of stenosis is significant at this point, and lower physical activity levels can trigger symptoms. As the vascular segment calcifies, the vessel loses its elastic property, impairing its dilation ability. Consequently, the blood vessels can no longer adapt to increased tissue demands by altering the diameter of the blood vessels. This leads to significant constriction and symptoms that can be triggered by lower levels of physical activity, causing the blood vessels to become stiff and rigid. This process can slowly lead to complete blockage of the blood vessel. Eventually, the fibrous cap may rupture, and a clot will form around it, completely blocking the vessel's lumen.  

The arterial pulse in the affected artery, potentially in the arteries running distally from it, may be weakened or impalpable. In areas with poor circulation, the skin may appear pale, feel cold to the touch, and become thinner. Hair in areas with poor circulation may weaken and thin. Nails may be weaker and cracked. Skin affected by poor circulation is more susceptible to infections, and the nails are more prone to fungal infections. Poorly healing wounds, ulcers, and eventually complete tissue necrosis and gangrene can occur. The risk of these complications, including poorly healing wounds and gangrene, is increased in individuals with diabetes. 

Lower limb localization
The abdominal aorta divides into two branches, the right and left common iliac arteries. The external iliac artery, an outer branch, supplies blood to the lower limb. In contrast, the internal iliac artery provides blood to the pelvis and external genitalia. 

Narrowing of the common iliac artery can cause lower limb pain, pain in the pelvis and lumbar spine, and erectile dysfunction in men. A narrowing in the abdominal aorta results in insufficient circulation in both common iliac arteries, with symptoms on both sides. 

The narrowing of the femoral artery in the leg leads to classic symptoms such as pain, cramping, and muscle weakness during physical activity. Hypoxic pain primarily manifests in the triceps surae muscle group during physical activity. The pulsation of the popliteal artery, as well as the other arteries in the leg, may be weakened or impalpable. 

The leg arteries, including the anterior and posterior tibial and fibular arteries, originate from the femoral artery at the knee level. These blood vessels supply arterial blood to the muscles acting on the leg and foot. Symptoms, typically including pain and cramping, usually manifest in the legs. The decrease in pulse can be felt in the back of the leg, between the first and second metatarsal bones (dorsalis pedis artery), and behind the inner ankle (posterior tibial artery). Symptoms in the upper limbs are much less common, and no functional stage classification exists.  

After taking a proper history, the following signs may be seen on the affected part of the body during the examination: the skin is pale, thin, dry, and cool to the touch. The hair is thinned and sparser than on the intact side. The nails are cracked, possibly showing signs of fungal infection. The skin between the toes can crack, and fungal infections can also appear. The color of the skin in stages III and IV may be purple, brownish-discolored, or completely black. Wounds and ulcers may appear on the foot or shin. The muscles are inactive due to pain provoked by movement, and atrophy quickly.

The ankle-brachial index (ABI) test measures the ratio of systolic blood pressure at the ankle to systolic blood pressure at the arm. Normal systolic pressure in the lower limb is higher than in the arm. This test should be performed with the patient in the supine position. The normal range for the ABI ratio is typically between 0.91 and 1.3. Values below 0.9 may indicate vasoconstriction, and severe vasoconstriction is suspected when the ratio falls below 0.4, per the American Diabetes Association guideline.  

ABI: Ankle-arm index, PAD: peripheral arterial disease

Ratschow test
The Ratschow position test, also known as Ratschow's maneuver, is a medical examination technique used to detect arterial circulatory disorders of the lower extremities, including peripheral arterial disease (PAD). It is used in conjunction with the ankle-brachial index (ABI) as part of the diagnostic process for PAD. During the Ratschow position test, the patient is placed in a specific position, often lying flat on their back with their legs elevated. The examiner lifts one or both limbs of the patient to approximately 45–60 degrees of hip flexion. This position allows blood to pool in the lower limbs. Then, the examiner observes the response of the patient's lower extremities, looking for any signs of pallor (pale color) or cyanosis (bluish discoloration), which can indicate inadequate blood flow to the extremities. This maneuver might increase the ischemia (lack of blood flow) in the limb and potentially provoke pain or discomfort, especially if there is a blockage or stenosis in the arteries. The test is positive if the leg turns white within one minute and the patient reports pain in the leg or foot.  

In the second part of the test, the examiner has the patient sit up with their legs hanging off the exam bed. The time it takes for the arteries to refill with blood (the leg regains color, and the pain subsides) indicates intact or reduced arterial circulation. With normal circulation, a leg that is hanging down will not only regain its normal color within 30 seconds but also become hyperemic (flushed). In patients with vascular conditions, the flushing response during testing might be slower to appear but more intense than in individuals without vascular issues. 

The test is double positive if the pain does not resolve within 30 seconds after the patient is seated. In this case, even the effect of gravity on arterial circulation is not enough to correct the arterial blood shortage. The test has multiple variations. In some cases, the limb can be held in more pronounced hip flexion, while in others, the patient can continuously perform ankle plantar and dorsiflexion with the lower limb raised. Increased hip joint flexion intensifies the impact of gravity, and the muscles, through their continuous movement, deplete available oxygen more rapidly, leading to the onset of symptoms. 

Functional tests
Walk test (walking distance): the test assesses how many meters the patient can walk without stopping due to ischemic pain in the lower limb. Based on Fontaine's scale, the absence of or minimal clinical symptoms in the form of tingling, numbness, and cold sensitivity define stage I. Stage IIa is intermittent claudication with a distance above 200 m, whereas stage IIb is below 200 m. Stage III accounts for rest pain, and grade IV comprises ulcers of gangrene and necrosis. Stages III and IV are referred to as critical limb ischemia. 

A key component of exercise therapy is local anaerobic interval training below ischemic pain tolerance or threshold. This involves performing short bursts of high-intensity exercise with the muscles affected by reduced blood flow due to the stenosis (e.g., calf muscles in the case of femoral artery stenosis).
The exercise intensity should be carefully determined beforehand by assessing the ischemic threshold. This is done by having the patient repeatedly perform a specific exercise until pain occurs in the working muscles. This pain signifies the ischemic pain threshold, representing 100% muscle work capacity (or 100% training load).
During the actual training, the intensity should be set at 90% of the maximum training load, ensuring that the exercise remains challenging but does not reach the pain threshold. This approach effectively stimulates the development of collateral circulation (new blood vessels) to bypass the blockage, thus improving blood flow and reducing symptoms. 

This test is performed in patients with a narrowing or blockage in the femoral artery. The patient should hold onto a stable surface for support and perform dynamic heel-rises repeatedly. The ischemic threshold is determined by counting the repetitions completed before the onset of pain (this represents 100% training load). The patient should maintain a consistent pace of approximately 60 repetitions per minute. With each repetition, they must avoid using their arms for assistance and ensure full plantar flexion (pointing their toes downwards). 

In interval training, the high-intensity phase means that the patient must carry out the exercises with a repetition rate of 90% of the ischemic threshold. In interval training, the low-intensity 'rest' phase is tailored to the patient's needs and condition. It can be a complete rest or involve gentle activities using different muscle groups. This phase aids recovery while maintaining some activity level, depending on the patient's fitness and exercise program goals. 

Stage III:
Rest pain or on minimal exertion. Also, the pain felt at night is frequent.
Aim: To improve the oxygen supply to resting tissues, slow down the progression of the disease, and prevent the need for limb amputation. In the third stage, the ischemic threshold is assessed using the Ratschow test, which identifies where a raised lower limb and the onset of pain mark the threshold for ischemia, set at 100%. The training is set at 90% of the threshold value on the affected limb.  

The therapy employed in Fontaine stage III operates with the influence of gravity on the blood vessels. During the training, the patient is lying on their back. The initial phase of the training commences with breathing exercises that aid in oxygenating the arterial blood. During the second phase, high-intensity movements are performed with the healthier and less affected lower limb. This improves the circulation in the affected lower limb using the consensual effect. The following phase enhances vasodilation; during the therapy session, the therapist lifts the affected limb to a level where the patient feels discomfort at 90% of their pain threshold but not exceeding it. After holding it in this position for a period, the therapist then lowers the same limb, allowing it to hang freely off the edge of the bed. The duration for which the leg hangs freely off the bed is at least as long as the time it was lifted or until visible reddening of the leg occurs. This method involves repeating these three steps—lifting the limb, holding it at 90% of the pain threshold, and then letting it hang freely off the bed—for 15–20 minutes. 

Mechanism of action: this therapeutic technique operates by utilizing the force of gravity to affect the flow of blood through the arteries. Lifting the lower limb makes peripheral arterial circulation more challenging due to gravity while enhancing veins' drainage. Gravity promotes increased arterial inflow into the peripheral arteries when the limb is lowered, improving blood supply. 

It is noted that vascular stenosis with severe functional limitation is less common in the upper limbs, implying that the described technique primarily applies to the lower limbs. In the case of the upper limbs, assessing functional capacity is not conducted in the same manner as for the lower limbs, meaning that the Fontaine classification is inapplicable. Instead, the ‘fist clenching test’ can be used to evaluate the ischemic threshold in the upper limbs. During the test, the patient raises both arms slightly above shoulder height, with elbows bent and forearms in a vertical position. In this position, the patient is required to clench their fists and subsequently relax their hands. The combination of gravity and the muscles’ increased need for oxygen due to fist clenching makes arterial circulation more challenging in the upper limbs during the test. The affected side of the hand turns white, grip strength is weakening, and pain becomes apparent. The number of repetitions or the elapsed time during these symptoms can determine the ischemic threshold. After lowering the arms, the hand gradually regains its normal color, and the time it takes to return to a normal color can also indicate arterial circulation. During the training, the ‘fist clenching test’ can be repeated up to 90% of the threshold, or fast wrist movements with low resistance (e.g., using a hand dumbbell) can be incorporated. 

Stage IV:
characterized by complete blockage of the arteries, leading to tissue death. In cases where the affected area is no longer responsive to exercise therapy, it indicates a severe condition where circulation and function cannot be improved through these means. In such cases, amputation of the limb may be necessary. Physiotherapy should be integrated into the rehabilitation after amputation. The rehabilitation goals, such as preventing joint contractures, preparing the stump for prosthesis use, teaching prosthesis utilization, and training position and location changes, are consistent with rehabilitation strategies employed after surgical treatment of traumatic amputations. However, it is crucial to note that patients who have undergone amputations due to vascular diseases, especially those with underlying circulatory problems, necessitate continuous medical care and treatment as circulatory patients. 

In severe arterial circulatory disorders, the positive outcomes achieved through physiotherapy alone may not be adequate to restore the patient's functions fully. In such instances, physiotherapy and other medical interventions are essential. This may include drug therapy, and, in some cases, invasive surgical procedures may be required to address the underlying circulatory issues and improve the patient's overall condition. Angioplasty, with or without the placement of a stent, is frequently recommended even in Fontaine stage II. Still, it becomes the primary method to restore circulation in stages III and IV. Angioplasty can establish flow through a shorter or longer section of a blood vessel. This surgical procedure can bring about a significant and immediate improvement in the condition and care of the affected vessel, thereby enhancing blood circulation to the affected area. However, atherosclerosis is a widespread disease of the vascular system. In some vascular segments, significant narrowing develops with severe symptoms. In other segments, the narrowing may be minor, with mild ‘masked’ or hiding symptoms, meaning that more severe symptoms in one area may overshadow or hide the milder symptoms in other areas, making them harder to detect or attribute to the underlying vascular issue. Before initiating exercise therapy, evaluating the functional capacity of the less affected limbs and other body parts is crucial. Based on this assessment, tailored training should be provided to enhance the function and strength of these less affected areas. During the therapy, it is crucial to pay close attention to the potential involvement of other organs, such as the heart and brain, as their condition can significantly impact the course and methods of therapy.  

Various rheumatological diseases, including rheumatoid arthritis and Sjögren's syndrome, can trigger secondary or consequential Raynaud's syndrome. Symptoms may also manifest in individuals with lupus and scleroderma.