Mitral Annular Calcification - Symptoms, Diagnosis, and Treatment

Introduction:

Mitral annular calcification, or MAC, refers to chronic degenerative changes that include multifactorial aspects of the cardiovascular system, especially the heart. The changes occur in the annular fibrosis ring that is within the mitral valve of the heart. The cause for such degenerative alterations is reported to be the repeated deposition of calcium and lipids in the mitral valve.

• The heart has four chambers- two upper sections called the right atrium and left atrium, and two lower sections called the right ventricle and left ventricles.

• Parallel to four chambers, the heart has four valves- mitral valve, tricuspid valve, aortic valve, and pulmonary valve.

• Valves are a crucial part of the heart’s structure.

• They open and close as the blood passes through them.

• They mainly regulate the entry and exit of blood into the heart’s various chambers.

• The four valves have the primary function of opening and closing according to the heart’s blood flow.

• The valves have flaps or leaflets that open and close.

• Valves with three leaflets open and close simultaneously.

• In order to avoid any sort of backflow of blood, the leaflets close, and visa verse is why they open.

The mitral or bicuspid valve allows blood to flow smoothly from the left atrium into the left ventricle. It has two leaflets. The mitral annulus of the mitral valve is a fibrous, saddle-shaped ring that is joined to the two leaflets of the mitral valve.

What Changes Occur During Mitral Annular Calcification?

Tissue damage, necrosis, and scarring are observed in the initial stages of mitral annular calcification. These damages to the endothelial tissues and cells are present at microscopic levels. They develop because of the heavy deposition of lipids, which is similar to atherosclerosis. Over time, lipid deposition leads to calcification as well as inflammatory changes within the cardiovascular system. The mechanical stress on the annular ring of the mitral valve due to the above-mentioned physiological changes leads to turbulence in the normal flow of blood and hampered the functioning of the mitral valve.

What Are the Signs and Symptoms of Mitral Annular Calcification?

The development of mitral annular calcification may take years. Depending on the time of onset, clinical manifestations and the case presentation may drastically vary. Once the condition has reached a later stage that is quite advanced, there are some signs and symptoms that are observed in the cardiovascular functioning of the patient. Mentioned below are a few of the signs and symptoms of mitral annular calcification.

• Shortness of breath.

• Chest pain.

• Fatigue.

• Dizziness.

• Fainting.

• Rapid weight gain.

• Irregular heartbeat.

• Fluttering sensation in the chest.

• Lightheadedness.

• Coughing.

• Swollen ankles.

• Bloating of the abdomen.

• Tightness in the chest.

• Difficulty sitting up.

• Insomnia.

• Inability to engage in physical activities.

• Tiredness after a short distance walk.

• Heavy breathing after and while climbing stairs.

• Enlargement of the liver.

• Palpitations.

• Swelling of the feet.

• High or low blood pressure depends on the mitral valve.

• Cold hands and feet.

• Clammy skin with bluish discoloration.

• Mumbling murmur.

• Fever in case of infection.

• Heavy breathing after and while climbing stairs.

• Enlargement of the liver.

• Elevation in the jugular vein.

• Abnormal pulse around the neck.

• Dyspnea (shortness of breath).

• Peripheral swelling or edema throughout the body.

What Are the Causes of Mitral Annular Calcification?

It has been widely reported that the development of mitral annular calcification is highly susceptible in patients who have an underlying cardiovascular disorder that has been long-standing and untreated or has been running in the family. Inflammatory changes in the heart due to such cardiovascular diseases result in malfunctioning of the valves.

Mentioned below are a few of the causes and etiological factors that may result in the formation and development of mitral annular calcification.

• Age.

• History of cardiovascular disease.

• Obesity.

• Atherosclerosis.

• Stress.

• High blood pressure or hypertension.

• Aortic stenosis (narrowing of aortic valves).

• Hypertrophic changes in the heart.

• Cardiomyopathy.

• Abnormal metabolism of calcium.

• Malfunctioned regulation of phosphorus.

• End-stage renal disease.

• Marfan syndrome (a genetic connective tissue disorder that affects multiple organ systems, characterized by tall stature, elongated limbs, and a predisposition to aortic aneurysms).

• Hurley syndrome (a chronic inflammatory skin condition characterized by recurrent painful nodules and abscesses in the armpits, groin, and other areas with sweat glands).

• Mitral valve prolapse.

• Chronic kidney diseases.

• Female gender.

How to Diagnose Mitral Annular Calcification?

Mitral annular calcification is observed in less than 10 % of the population. Mitral annular calcification may be diagnosed during a regular consultation with a physician post a few extra diagnostic tests. A stethoscope can pick up any abnormal heart murmurs and regurgitation sounds. To confirm the presence of valvular regurgitation or valvular stenosis, as well as any abnormality with any of the cardiac valves, additional tests such as those mentioned below may be suggested. Physical examination and a detailed account of medical as well as drug history are vital for the diagnosis of mitral annular calcification.

• Electrocardiography.

• Ultrasound of the heart.

• Complete blood picture.

• Doppler echocardiography.

• X-ray of the chest.

• Transesophageal echocardiogram.

• Magnetic resonance imaging of the heart.

• Catheterization.

What Is the Treatment of Mitral Annular Calcification?

MAC or mitral annular calcification does not require any specific treatment because it does not pose a fatal amount of threat to the cardiovascular system. The mitral valve should be regularly checked for proper functioning. In case the mitral valve is getting obstructed due to mitral annular calcification, certain treatment modalities are available. The healthcare provider is the one who decides which management plan would work in a positive manner in accordance with the diagnostic results as well as the clinical presentation of the patient suffering from mitral annular calcification. Mentioned below are the treatment options for mitral annular calcification.

• Open heart surgery.

• Mechanical valve insertion.

• Bioprosthetic valve repair.

• Mitral clip.

• Balloon valvuloplasty.

• Transcatheter aortic valve replacement or TAVR.

• Transcatheter mitral valve replacement or TMVR.

• Cardiac rehabilitation.

• Beta-blockers.

• Endocarditis prophylaxis.

Conclusion:

MAC, or mitral annular calcification, is a cardiovascular disease of the mitral valve of the heart that results in the deposition of lipids which eventually leads to calcification of the annular ring. The disease can be prevented by several measures that focus on living a heart-healthy lifestyle and reducing foods rich in cholesterol and fats. Mitral annular calcification is not a life-threatening condition.