Pulmonary artery aneurysm is a pathological local expansion of a large vessel exiting the right ventricle of the heart and delivering venous blood to the small circulatory circle, or its branches. Usually the disease is asymptomatic, sometimes patients experience chest pain, shortness of breath, hoarseness of voice, hemoptysis and pulmonary bleeding. It is diagnosed using functional and radiological (chest X-ray, angiopulmonography) examination methods, CT and MRI of lung vessels. After diagnosis, surgical excision of the aneurysm is performed.
ICD 10
I28.1 Pulmonary artery aneurysm
Meaning
Pulmonary artery aneurysm is a rare vascular pathology, may be congenital or acquired. It is detected in adulthood, mainly in people over 50 years of age. There is a predominance of female patients – 57% of the total number of patients. In approximately 80% of cases, the disease is asymptomatic.
Idiopathic isolated pulmonary artery dilation accounts for 0.6% of all congenital anomalies. In 50% of cases, an aneurysm is combined with other malformations. Usually, the expansion of pulmonary vessels is accompanied by congenital and acquired cardiovascular pathology. Mortality in pulmonal artery aneurysm is 5-6%.
Pulmonary artery aneurysm causes
It is extremely rare that an aneurysm of the pulmonary trunk or its branches occurs independently, regardless of other pathological changes in the heart or lungs. This condition is usually congenital. More often, the disease accompanies other diseases of the cardiovascular or respiratory systems or develops against their background. The main causes of pulmonary vascular aneurysms are:
- Cardiovascular pathology. The appearance of an aneurysm is usually caused by the presence of defects in the atrial or interventricular septa, an open arterial duct, and other congenital or acquired heart defects. The cause of the local expansion of the walls of the pulmonary artery can be any disease of the cardiovascular system, provoking the development of secondary pulmonary hypertension.
- Infectious and parasitic diseases. The formation of an aneurysm is sometimes provoked by arteritis, developing with visceral syphilis, deep pulmonary mycoses, schistosomiasis. With cavernous pulmonary tuberculosis, a Rasmussen aneurysm is formed, characterized by stretching of the walls of the artery in the cavity of the cavity.
Vascular aneurysm may appear against the background of severe chronic respiratory diseases, fibrothorax, complicate the course of systemic vasculitis, Hughes-Stovin syndrome. The cause of pathology is sometimes injuries of the respiratory tract or damage to the vessels of the respiratory system that occurs during medical manipulations (iatrogenic).
Pathogenesis
Presumably, a prerequisite for the development of the disease is the congenital inferiority of a section of the pulmonary artery wall. An increase in pressure in the small circle of blood circulation causes its local stretching and thinning. In aneurysmal expansion, turbulence of the blood flow occurs, which leads to disruption of hemodynamic processes in the distal areas of the vascular network.
The lateral pressure on the stretched wall of the organ gradually increases, its degenerative-dystrophic transformation progresses, and the risk of rupture increases. Sometimes, due to the deposition and calcification of thrombotic masses, a thickening of the wall of the aneurysmal sac is formed.
Classification
According to the time of occurrence of a pulmonary artery aneurysm is divided into congenital and acquired, according to the etiological factor – into idiopathic and associated with other diseases. Depending on the site of the lesion of the vascular wall, aneurysms of the pulmonary trunk, its right or left branches, distal pulmonary arteries are distinguished.
Aneurysmal extensions of the sac, fusiform, mushroom-shaped and mixed forms are revealed. The following variants of the disease have a certain clinical significance in modern pulmonology:
- A true aneurysm. All layers of the vascular wall are involved in the pathological process.
- False aneurysm (pseudoaneurysm). The walls of the formation are represented only by the adventitial vascular membrane, the blood-filled cavity communicates with the lumen of the vessel. The risk of rupture with this type of pathology is much higher than with a true aneurysm.
Pulmonary artery aneurysm symptoms
In most cases, the disease is asymptomatic for a long time. Clinical manifestations depend on the localization and magnitude of the pathological formation. Signs of the disease are more often present with pseudoaneurysms of large sizes. The patient may be concerned about general weakness, increased fatigue, shortness of breath during movement, a feeling of palpitation. Sometimes there are aching dull pains in the chest in the projection of education, hemoptysis. When the recurrent nerve is compressed by an aneurysm, the timbre of the voice changes – hoarseness or hoarseness occurs.
Very often, with aneurysms of the arteries of the small circulatory circle, the clinical symptoms of the background disease prevail. With cardiovascular pathology, chest pains, rhythm and conduction disturbances, limb edema and other signs of chronic heart failure are observed. Diseases of the respiratory system are characterized by the presence of cough with or without sputum, bronchospastic syndrome, shortness of breath.
The most severe manifestation of the pathological process is an acute pulmonary heart, which develops due to a rupture of a vessel. The patient suddenly has sharp intense pain in the chest area, accompanied by pronounced inspiratory dyspnea, hemoptysis. Difficulty breathing is present at rest, sharply increases with the slightest exertion or conversation. The skin becomes bluish, the cervical veins swell. There is a decrease in blood pressure, tachycardia. The skin is pale, covered with a sticky cold sweat. Nausea, vomiting, and pain in the right hypochondrium are possible.
Complications
Over time, pathological changes in the walls of aneurysmal formation can progress – the walls become thinner, lose density and elasticity. There is a rupture or dissection, hemorrhage into the pulmonary parenchyma and the development of infarct-pneumonia. In case of violation of the integrity of the aneurysm membranes communicating with the bronchial lumen, pulmonary bleeding occurs. With a breakthrough into the pericardial cavity, a tamponade of the heart is observed.
Rasmussen’s aneurysm often becomes a source of massive hemoptoe, which is one of the direct causes of death of tuberculosis patients. Separation and migration of thrombotic masses from the cavity of aneurysmal protrusion of the pulmonary artery can lead to thrombosis of cerebral vessels and stroke.
Diagnostics
Usually, a diagnostic search for suspected pulmonary vascular aneurysm is carried out by pulmonologists together with vascular surgeons. During the initial examination, signs of background pathology are revealed. Auscultatively, with the expansion of the pulmonary trunk, diastolic noises are heard in the II-III intercostal space to the left of the sternum, the accent of the II tone, To confirm the diagnosis are performed:
- Cardiodiagnostics. The electrocardiogram usually shows signs of overload of the right parts of the heart, hypertrophy of the right ventricle. Ultrasound examination (EchoCG) can detect the expansion of the main pulmonary arteries and trunk, identify the insufficiency of the semilunar valves and hemodynamic disorders.
- X-ray diagnostics. The X-ray picture depends on the localization of the aneurysmal sac. With the expansion of the trunk or its left branch, a rounded formation in the area of the left root is determined on the chest x-ray. Aneurysm of the right branch is manifested by an increase in the cross-section of the artery in the form of a comma localized in the zone of the right root. Pathology of peripheral vessels is represented by single or multiple dense rounded shadows. Angiopulmonography allows you to clarify the localization of the process.
- CT, MRI of pulmonary vessels. They are also used to clarify the location of the aneurysm. Allow you to estimate its size and wall thickness. They are more accurate and less invasive methods compared to similar X-ray examination of blood vessels.
Taking into account the polyetiological nature of the disease, doctors involved in the treatment of the background process – phthisiologists, dermatovenerologists, rheumatologists can take part in the diagnosis process. Sometimes a vascular aneurysm is difficult to differentiate from a malignant tumor of the lung or mediastinum, aneurysmal expansion of the descending part of the aorta. In such cases, an oncologist or cardiologist is additionally prescribed.
Pulmonary artery aneurysm treatment
After determining the localization of the pathological expansion of the vessel, surgical correction of the aneurysm is performed. The expansion is excised with a decrease in the diameter of the artery or resection of the vessel section with subsequent prosthetics. The second stage of surgery is the stenting of the vessel. If it is impossible to resect an aneurysm, palliative surgery is performed – strengthening the wall of the protrusion with a dacron prosthesis. Sometimes, with small asymptomatic aneurysms, wait-and-see tactics are used. The patient is regularly observed by the attending physician, who assesses the state of pathological protrusion in dynamics. If the aneurysm increases in size, it is resected.
Prognosis and prevention
The prognosis with timely surgical treatment is favorable, relapses are very rare. In the absence of treatment, there is a risk of rupture of the wall of the formation, which poses a threat to the patient’s life. Non-operated patients often die from acute right ventricular failure or massive pulmonary hemorrhage. Preventive measures include early (before the appearance of pulmonary hypertension) surgical correction of congenital heart defects, treatment of background processes.
Literature
- Idiopathic asymptomatic main pulmonary artery aneurysm: surgery or conservative management? A case report. Vural AH, Türk T, Ata Y, Göncü T, Ozyazicioglu A. Heart Surg Forum. 2007;10(4):E273-5. link
- An operative case of bilateral peripheral pulmonary arterial aneurysms. Inaba H, Nagashima Y, Oota S, Itoh Y, Etoh T, Honda A, Nakajima H, Muro H. Kyobu Geka. 1997 Apr;50(4):331-4. link
- Idiopathic main pulmonary artery aneurysm. Nair KK, Cobanoglu AM. Ann Thorac Surg. 2001 May;71(5):1688-90. link
- Pulmonary artery aneurysm secondary to patent arterial duct and infection: A case report and review. Zhang L, Li Y, Lv Q, Yuan L. Echocardiography. 2018 Nov;35(11):1878-1881. link
- Multiple pulmonary-artery aneurysms due to mucoid vasculopathy–angiographic and histological observations. Gupta AK, Sandhyamani S, Ravimandalam K, Rao VR, Neelakandhan KS, Joseph S, Unni M, Rao AS. Thorac Cardiovasc Surg. 1993 Jun;41(3):189-92. link
