Aortic insufficiency: causes, symptoms, diagnosis and treatment of aortic regurgitation
Aortic insufficiency, also known as aortic regurgitation, is a heart condition characterised by a reflux of blood from the aorta into the left ventricle due to an abnormality of the aortic valve
In these cases, the valve does not close tightly, which prevents the blood from being properly directed to the peripheral organs.
This is a serious condition that, if not treated properly, can lead to serious complications for the patient, who may suffer arrhythmias, heart failure or myocardial infarctions.
There are several causes of aortic insufficiency
It can be congenital, i.e. due to malformations or hereditary diseases, or it can be acquired, i.e. due to heart disease, hypertension or severe infections, or due to the normal ageing process.
Patients suffering from aortic insufficiency may present with symptoms such as weakness, fatigue, palpitations and chest pain.
Depending on the specific case, treatment of this condition may involve drug therapy or, in more severe cases, surgery.
What is aortic insufficiency?
Aortic insufficiency is a cardiac pathology belonging to the group of valvulopathies, i.e. diseases affecting the heart valves. In this case, it is the aortic valve, one of the four valves responsible for controlling blood flow within the heart muscle, that is affected.
It connects the left ventricle with the aorta, the main artery of the human body that carries blood to peripheral organs and tissues.
In patients with aortic insufficiency, this valve has an abnormality that prevents it from closing tightly, leading to a reflux of blood into the ventricle during diastole.
In general, this is a rather common disease, which has a high incidence especially in elderly patients.
If it is not treated properly, it can lead to severe complications for the patient: due to the decrease in cardiac output, heart failure can occur, resulting in insufficient blood supply to the body.
Nevertheless, in most cases, aortic insufficiency is well-tolerated and symptoms may take years to appear.
It is possible to distinguish three levels of severity of the disease
- mild insufficiency: characterised by minimal blood regurgitation, which does not lead to significant symptoms, but which must be closely monitored over time;
- moderate insufficiency: blood reflux is such that it can lead to ventricular hypertrophy which, in the long run, can lead to irreversible alterations in cardiac structure and function;
- Severe insufficiency: this can be the result of degeneration of the disease or can arise suddenly due to infections and other heart diseases. It results in heart failure symptoms and can lead to a lowered life expectancy if not treated properly.
Anatomy of the heart
In order to better understand the importance of the function performed by the aortic valve, it may be useful to briefly review the anatomy of the heart.
It is possible to divide the heart muscle into two halves: a right and a left side; each of the two halves consists of two distinct cavities within which blood flows, namely the atria (upper) and the ventricles (lower).
The atria and ventricles are separated by the interatrial septum and the interventricular septum respectively, while the atrium and ventricle of the same half are connected by the atrioventricular valves.
There are two atrioventricular valves: the tricuspid valve on the right side of the heart, and the mitral valve on the left side; their function is to prevent the reflux of blood from the ventricle into the atrium.
Two other valves, known as the semilunar valves, are also found in the ventricular cavities: the pulmonary semilunar valve, which controls the flow of blood from the right ventricle to the pulmonary artery, and the aortic valve, which regulates the flow of blood from the left ventricle to the aorta.
The movements required by the heart to pump blood within the myocardial muscle and into the rest of the body are called systole (contraction phase) and diastole (relaxation phase).
Causes of onset
As already mentioned, aortic insufficiency can be distinguished into congenital forms, i.e. due to factors present from an individual’s birth, and acquired forms, i.e. developed over time due to traumatic events, pathological disorders or with advancing age.
The causes of congenital aortic insufficiency are generally related to
- Malformations, e.g. bicuspid aortic valve.
- Genetic diseases, e.g. Marfan syndrome and Ehlers-Danlos syndrome, two hereditary diseases affecting the connective tissues.
- Osteogenesis imperfecta, a genetic disorder characterised by bone fragility that predisposes to fractures and injuries.
Causes of acquired aortic insufficiency include
- Ageing: advancing age sets in motion a general degenerative process, which can cause the valve cusps to thicken and become stiffer due to a build-up of calcium deposits on the valve, leading to a decreased effectiveness of the orifice’s hermetic closure mechanism.
- Endocarditis: a severe inflammation, generally of bacterial origin, which can affect the inner lining of the heart (endocardium) and the heart valves.
- Hypertension: this is a pathological condition of a chronic nature that results in a chronic and abnormal rise in blood pressure.
- Other valvulopathies, in particular aortic insufficiency is often associated with aortic stenosis.
- Infections and rheumatic fever: this is an inflammatory process due to a bacterial infection with group A beta-hemolytic Streptococcus. Due to the infection, the immune system starts to react against the organism to be defended.
- Traumatic events.
In rarer cases, aortic valvulopathy can also occur as a consequence of other disorders such as systemic lupus erythematosus, ankylosing spondylitis, syphilis, reactive arthritis, Behçet’s disease or aortic dissection.
What are the main symptoms
As mentioned above, aortic insufficiency can have different levels of severity: in the early stages, the disease presents almost asymptomatically, with minimal regurgitation detectable only by cardiac examination; however, this condition tends to worsen over time and, in the long run, can lead to increasingly severe symptoms.
From the earliest stages, it is possible to detect in patients with aortic insufficiency, a heart murmur, i.e. an abnormal noise due to the turbulence of blood flow as it passes through the malfunctioning valve.
Symptoms associated with aortic insufficiency include
- Sense of tiredness and weakness;
- Inability to perform physical exertion;
- Dyspnoea on exertion, i.e. difficulty breathing during physical activity;
- Asthenia or feeling faint;
- Lower limb oedema;
- Angina pectoris or chest pain;
- Syncope or presyncope, due to reduced blood supply;
- Cardiac arrhythmias or alterations in the rhythm of contraction of the heart;
In order to detect aortic valvulopathy, a thorough cardiological examination is required, following which the cardiologist may prescribe a series of specific tests.
During the check-up, the doctor carries out an objective test to assess the symptoms reported by the patient, auscultates the heart to detect any heart murmurs, and carefully examines the patient’s personal and family history to check for any previous pathologies or genetic diseases that may lead to heart problems.
The investigations necessary to diagnose aortic insufficiency may include
- Electrocardiogram (ECG): measures the heart’s electrical activity, allowing the detection of hypertrophy and functional overload of the left ventricle.
- Echocardiography: allows us to obtain an image of the cardiac structure and show the anatomical structures of the heart muscle, highlighting any malformations and abnormalities in the thickness and size of the cavities.
- Echo-colour-doppler: this is a special type of ultrasound scan that makes it possible to analyse the blood flow inside the heart, and estimate the extent of blood reflux between the aorta and the left ventricle in diastole, to assess the severity of the pathology.
- Chest X-ray (chest X-ray).
- Stress test.
- Cardiac catheterisation: this is an invasive test involving the introduction of a catheter up to the heart, in order to measure the pressure inside the ventricles and the size of the valve orifices, so as to assess the severity of the insufficiency.
Care and treatment
The most suitable treatment for aortic insufficiency may vary depending on the nature of the disorder, the extent of the regurgitation and the severity of the reported symptoms, or the age of the patient.
As already noted, in cases of mild insufficiency, no treatment is necessary, but it is important to scrupulously monitor the condition with periodic cardiological examinations.
Generally speaking, there are no specific drugs for the treatment of aortic insufficiency, however, drug therapy can be followed to control the more severe symptoms and avoid possible complications.
Medications that can be used include:
- ACE inhibitors to reduce cardiac stress;
- Angiotensin II receptor antagonists (ARBs);
- Calcium channel blockers;
- Diuretics, in the case of hypertension and oedema of the lower limbs;
- Antibiotics, in the case of endocarditis and infections.
In the case of young patients with severe aortic insufficiency, the most suitable approach involves surgical therapy to repair or replace the aortic valve.
The purpose of repair is to remodel the valve to restore its original function, but unfortunately only in a small number of cases.
It may be performed by thoracotomy or by less invasive approaches such as minithoracotomy or tanscatheter.
When repair is not possible, the aortic valve can be replaced with an artificial or biological type.