Aortic aneurysm

Aortic aneurysm - pathological local (saccular) protrusion of the wall or diffuse (circular, exceeding the diameter of the normal aorta by half) widening the aorta. Localization distinguishes the aneurysm of the sinus of Valsalva, the ascending section, the arc and the descending section of the thoracic aorta, and the aneurysm of the abdominal aorta. According to etiology, congenital aortic aneurysms (the rarest) and acquired non-inflammatory (atherosclerotic, traumatic - most frequent) and inflammatory (syphilitic, tuberculous, rheumatic, infectious) infections are noted; The average age of patients is 40 to 70 years.

Clinical picture . Aneurysm of the thoracic aorta may be manifested by pain in the region of the heart, dyspnea, hoarseness of the voice, objectively there may be signs of aortic insufficiency; Aneurysm of the abdominal aorta - a recurring pain in the abdomen or waist, a sensation of pulsation, while sometimes it is possible to palpate the pulsating formation to the left of the spine in the navel or above and listen to the systolic murmur over it.

Prognostically unfavorable is the dissecting aneurysm of the aorta, characterized by necrosis and rupture of part of its wall with subsequent stratification by its blood. In the initial period of exfoliation, the inner and sometimes the middle shell of the aorta is torn while maintaining the integrity of its outer shell. Later, the blood penetrating under great pressure exfoliates the entire wall of the aorta and breaks the outer shell, which leads to instant death of the patient from massive internal bleeding. In other cases, the spread of exfoliation in the proximal direction leads to hemopericardium, aortic valve detachment, severe aortic insufficiency, occlusion of the coronary arteries of the heart. The exfoliation can be terminated by repeated breakthrough of the inner aortic membrane below the place of initial exfoliation. There is a so-called double-barreled gun; However, such successful cases of self-healing are extremely rare. Dissecting aortic aneurysm often occurs in elderly men with atherosclerosis and arterial hypertension in history, less often with syphilitic aortitis. Marfan syndrome, congenital aortic valve defects also belong to risk factors for aortic dissection.

The disease begins acutely, the tempo of rapid development. The main symptom of the disease is severe chest pain, irradiating in the back and often extending into the epigastric region. The patient is agitated, rushes, finds no place in pain. Often immediately after the pain develops a picture of a severe collapse with a fall in blood pressure, a filiform pulse, peripheral manifestations of vascular insufficiency; It is almost never possible to remove a patient from a collapse. In other cases, the first pain attack is accompanied by a sharp increase in blood pressure, the appearance of a significant asymmetry of pressure on the right and left hands, sometimes symptoms of cerebral circulation, episodes of loss of consciousness.

After the first severe pain attack, there may come a short-term relief, followed by a new bout of previous pains. The alternation of painful attacks and light intervals is due to the fact that the stratification of the aortic wall occurs sometimes in several stages. In addition, the involvement of new sections of the aortic wall in the process of separation can change the place of the greatest severity of pain. After the initial attack of pain in the chest in the future, it can be localized mainly in the abdomen, lower back, which should be taken into account in diagnosis. Involvement in the process of the abdominal aorta is usually accompanied by a violation of blood circulation in the basin of the major mesenteric vessels with the addition of a picture of severe intestinal obstruction. In half of cases, objective examination reveals aortic insufficiency with typical diastolic noise at the aortic listening point, cardiac tamponade , ischemia of the brain and spinal cord, limbs (which makes it impossible to determine blood pressure on one or both arms). From the moment of the initial tearing of the inner shell to the final breakthrough of the outer shell and the patient's death passes from several minutes to several days, during which short periods of relative well-being sometimes occur.

The diagnosis of exfoliating aortic aneurysm can be confirmed by X-ray and ultrasound examination and verified with aortography in the conditions of a specialized institution.

The dissecting aortic aneurysm usually has to be differentiated from myocardial infarction, which presents considerable difficulties due to the similarity of pain manifestations and symptoms of both diseases in general, especially in the initial period of the disease.

It should be borne in mind that the anticoagulants used in acute myocardial infarction are not contraindicated in the dissecting aortic aneurysm.

Treatment . Emergency care for suspected exfoliation of the aortic aneurysm is to create absolute rest, removal of the pain syndrome by administering 1 to 2 ml of a 1% morphine solution subcutaneously or intravenously. For emergency blood pressure lowering at the prehospital stage, nifedipine 10 to 20 mg sublingually (under the tongue) every 2 to 4 hours can be used - the drug is sufficiently effective and safe. A patient with suspicion of exfoliating aneurysm of the aorta is subject to urgent hospitalization provided that absolute rest during transportation is observed.

In the conditions of a specialized department for correction of elevated blood pressure with a suspected aortic aneurysm rupture, combined sodium therapy with nitroprusside and beta-blockers intravenously (to prevent sodium nitroprusside induced cardiac output and further intima aortic damage) is indicated. The aim of the therapy is to lower the blood pressure to a minimum level compatible with adequate perfusion of the brain, heart and kidneys (usually systolic blood pressure is 100-120 mm Hg, diastolic - no more than 80 mm Hg). Alternatively, verapamil may be administered intravenously at a dose of 0.05 mg / kg or labetalol intravenously at a dose of 5 to 20 mg, then 20 to 40 mg every 10 to 20 minutes until the required blood pressure is lowered or a total dose of 300 mg is reached. Labetalol reduces the overall peripheral resistance, without significantly affecting cardiac output, which makes it possible to use this drug as monotherapy for the dissection of the aorta; After an emergency correction of blood pressure and the end of infusion, it is possible to switch to taking the drug inside (100-200 mg 2-4 times a day). The use of these means requires strict ECG monitoring, heart rate and blood pressure, which limits the possibility of their use in the prehospital stage.

When the aortic dissection aneurysm is performed successfully, emergency aortic prosthetics are performed, which makes the correct early diagnosis of this terrible disease especially important. After an emergency correction of arterial hypertension, a survey is performed to verify the diagnosis (chest X-ray, ultrasound) and a consultation of the vascular surgeon to decide on the need for an operational benefit. The operation consists in removing the aortic site with an aneurysm and replacing it with an alloprosthesis. Contraindications to surgery are severe concomitant diseases, complicated by respiratory, cardiac, renal insufficiency. Without surgical treatment, the prognosis is usually unfavorable, the lethality within the year reaches 90%. As a supportive antihypertensive therapy in anticipation of surgery or if it is impossible to use it, calcium antagonists and beta-blockers are used to maintain systolic blood pressure at a level of no more than 130-140 mm Hg. Art.