Arterial occlusion
[1] Depending on the extent of ischemia, symptoms of arterial occlusion range from simple soreness and pain that can be relieved with rest,[3] to a lack of sensation or paralysis that could require amputation.
Without proper prevention or management, these diseases can progress into life-threatening complications of myocardial infarction,[7] gangrene,[8] ischemic stroke,[9] and in severe cases, terminate in brain death or cardiac arrest.
[16] Signs and symptoms of arterial occlusion depend on several factors, including the location, extent, and onset of blockage.
[3] The commonest symptom of arterial occlusion is intermittent claudication, which consists of a painful, aching sensation in the affected muscle.
The clinical presentation of ischemia consists of the 6 Ps, including pallor, pain, paresthesia, paralysis, pulselessness, and poikilothermia.
[1] This includes gas bubbles,[18] fatty deposits, amniotic fluid,[19] blood clots, and foreign material.
[11] This leads to turbulent blood flow in the arteries, affecting oxygen supply to tissues downstream.
[25] In CAD, atheromatous plaque formation in a coronary artery limits oxygen supply to cardiomyocytes, impairing heart contractility.
Primarily, the accumulation of cholesterol in the bloodstream from high-fat diets lead to atherosclerotic occlusion and its clinical consequences.
A diet low in saturated and trans fats with an abundance of vegetables, fruits, and grains may lower the incidence of CAD.
[5] Once blood flow is impeded, ischemic muscle cells switch from aerobic to anaerobic metabolism to cope with oxygen scarcity.
[6] Impairment of pulmonary circulation leads to severe ventilation-perfusion mismatching of the lungs,[30] terminating in hypoxemia and respiratory failure.
Most PEs are sequelae of Deep Vein Thrombosis (DVT), resulting from the breakage and propagation of a venous thrombus formed within the extremities to a pulmonary artery.
[32] Immobility reduces the rate of leg muscle contraction, enhancing thrombus formation in vessels of the calves that may propagate to the lungs.
A myocardial infarction (MI), or heart attack, arises from complete occlusion of a coronary artery.
[7] The thrombus deposits on the ruptured plaque to completely block the coronary artery, halting oxygen supply to cardiomyocytes.
[36] Lactate accumulation reduces contractility and eventually necroses cardiomyocytes, releasing their troponin storage into the bloodstream.
Diagnostically, STEMI displays prolonged ST-segment elevation in ECG traces,[34] and is thus named 'ST-Elevation Myocardial Infarction'.
[8] Gangrene is a complication of prolonged PAD, leading to shriveling, blackening, and infarction of peripheral tissue, commonly in the extremities.
Any interruption of blood supply causes neurons to switch to anaerobic metabolism,[37] exhausting intracellular ATP levels.
However, those with intermittent claudication struggle to maintain standard values of systolic pressure, while recovery back to baseline is prolonged.
The technique utilizes high-frequency sound waves for visualization of flow direction and velocity within the arteries in an area of interest.
The B-mode transducer allows for an image of the vessel to be obtained, providing visual cues on the extent of occlusion.
[39] Traditionally, angiography is an invasive technique which involves inserting a flexible plastic catheter into the artery of interest.
This contrast material does not permanently discolor any organs, but simply interacts with X-rays to produce a more precise diagnosis.
[41] Due to technological advances, clinicians have begun to use a less invasive approach called Multi-Detector Coronary Tomography (MDCT) angiography.
An embolectomy is a procedure conducted when a blockage moves from its original site to another place in the body, thus forming an embolus.
Anticoagulants such as warfarin and antiplatelets such as aspirin and clopidogrel reduce the risk of thrombosis by making blood flow easily through arteries.
