sztenózisa

Sztenózisa, commonly referred to as stenosis, denotes the abnormal narrowing of a hollow organ, vessel, or duct, leading to reduced flow of blood, air, bile, urine, or other substances. It can affect a range of structures, including arteries and heart valves, the spinal canal, the bile duct, and segments of the gastrointestinal or respiratory tracts. The condition is usually identified by a gradient or obstruction at the narrowed site and may be present from birth or develop later in life.

Common forms include vascular stenosis (such as carotid or renal artery stenosis), cardiac valve stenosis (notably aortic stenosis), spinal stenosis, and luminal strictures of the gastrointestinal or biliary tracts. The underlying causes are diverse and include congenital malformations, atherosclerosis, inflammatory or autoimmune processes, scar formation after injury or surgery, infections, and tumor compression. Risk factors overlap with those for atherosclerotic disease, such as age, hypertension, diabetes, hyperlipidemia, and smoking.

Symptoms vary by location. Vascular or valvular stenosis may cause chest pain, shortness of breath, syncope, or reduced distal perfusion. Spinal stenosis can produce back or leg pain with activity and neurogenic claudication. Bowel or airway stenosis may cause obstruction or breathing difficulties. Some cases are asymptomatic and discovered incidentally through imaging for other reasons.

Diagnosis relies on a combination of physical examination and imaging, including Doppler ultrasound, computed tomography (CT) or magnetic resonance (MRI) angiography, echocardiography, endoscopy, or invasive pressure measurements to assess gradients across the narrowed segment.

Treatment depends on site and severity. Options include risk-factor modification and medical therapy, balloon angioplasty with or without stent placement, valve repair or replacement, endarterectomy, or surgical decompression or bypass. Prognosis improves with timely diagnosis and appropriate intervention, though outcomes are highly site-specific.