The heart and heart valves

Like a hydraulic pump pushes the water in the water network of our cities, the heart - for all practical purposes a muscle pump - allows the blood to reach the entire human body, supplying the necessary nourishment, through a complicated system of pipes: the arteries.

It is located in the middle of the chest, inside the mediastinum, and it beats 100 thousand times a day on the average (around 70 times per minute).  Enclosed in a membranous sac - called the pericardium - the heart of an adult has walls defined in three layers: the epicardium (the outermost layer), the endocardium (the inner layer) and the myocardium (the intermediate layer). It weighs around 300 grams - the size of a fist - and can be divided into two parts: right heart (atrium and ventricle), which moves venous blood (full of carbon dioxide) towards the lungs; left heart (atrium and ventricle) whose task is to send arterial blood coming from the lungs (rich in oxygen) to the entire body. To work properly the heart needs electrical pulses - the vital spark originates from the cells known as pacemaker cells - and mechanisms or cardiac valves that allow the blood (700 litres in 24 hours, 5 liters per minute) to flow in a single direction without ever “turning back”.  There are 4 cardiac valves: tricuspid valve and pulmonary valve, both located in the right heart; mitral valve and aortic valve, located in the left heart. As it cannot capture oxygen from the blood that flows inside it, its supply is guaranteed by arterial branches - which recall the structure of a tree - called coronaries: both the right coronary and the left coronary originate from the aorta; after the first segment called common trunk, the left coronary is differentiated in anterior descending and circumflex. Other smaller blood vessels descend from the three main coronary branches; their purpose is to reach deep into the heart muscle in order to guarantee optimal blood supply to each individual point.

Mitral valve

Mitral valve is a bi-leaflet structure located inside the heart that, thank its harmonic movements regulates the flow from the left atrium to the left ventricle.
It is named ‘mitral’ because the shape is similar to the bishop headgear (the mitre).
The mitral valve is very close to another important structure, the aortic valve, the finally conveys the blood from the left ventricle to the ascending aorta. Importantly, there is a fibrous tissue that connects tightly the mitral to the aortic valve, and anatomically, these two valves may even be considered as a common valve.
‘Mitral disease’ refers to all the pathologies that can affect the normal functioning of the mitral valve. If the valve ‘leaks’ blood to the left atrium, it is called mitral regurgitation or insufficiency, vice versa if the valve ‘blocks’ the flow from the left atrium to the left ventricle, such a disease is named mitral stenosis.
However the latter is a less common disease than the regurgitation or insufficiency.
What can cause a mitral disease?  The etiologies are very different. We must say that everyone can be affected by regurgitation or stenosis at very different age, however there are some conditions that are important risk factor, such as collagen and connective tissue disease.
Symptoms can be deceiving (for some times patient may remains asymptomatic), however in some circumstance such in the case of rupture of one of the chordae of the valve, intense respiratory fatigue can happen.
Also, palpitation can be very common symptom.
Normally the mitral valve is replaced when is stenotic, and is repaired in case of regurgitation (so the native component of the valve are preserved).
Nowadays, experienced centers can achieve almost 100% of repair rate.

Disease and treatment

Mitral Academy is specialized in mitral valve diseases and treatments

Frequently Asked Questions

If I have mitral valve problems could I have a heart attack?

Sometimes acute mitral regurgitation is a direct consequence of myocardial infarction, as the latter may cause the papillary muscles underlying the valve leaflets to rupture. Therefore, as a first step, cardiovascular prevention must involve the health of the coronary arteries, which supply blood to the heart, to prevent severe ischaemia (lack of oxygen) due to the presence of atherosclerotic plaques obstructing the coronary vessel lumen.

After mitral valve surgery will I be an invalid forever?

Attention to every mode of physical activity should be maintained in the weeks preceding the operation so as not to increase the organic damage caused by the diagnosed mitral regurgitation. After the operation, when a convalescence and rest period has passed and if there are no other pathological manifestations that might advise abstention from specific sports/types of exercise, nothing will prohibit the normal and gradual resumption of your daily routine, whilst following the therapeutic indications given by the specialist. 

What will my life expectancy be after mitral valve repair/replacement?

Mitral valve repair is the preferred intervention in cases of valvular insufficiency with significant blood regurgitation and it has a very high degree of feasibility: over 90% of patients is judged to be eligible for this treatment. Replacement with a biological or mechanical prosthesis is implemented instead when severe mitral stenosis is present (narrowing of the valve opening): in these cases also the percentage of clinical success is significant and the postoperative quality of life quite satisfactory. It is crucial not to postpone the valve repair or replacement solution for too long, thus avoiding the risk of severe left ventricular dysfunction.

Does the repaired/replaced valve require special care over time?

The answer is yes, but let’s look at it in more detail: anticoagulant drugs, necessary for blood fluidification, are prescribed for life to those who have undergone surgery for mitral valve replacement with a mechanical prosthesis; this type of pharmacological therapy is usually not necessary in situations in which the mitral valve has undergone repair plastic surgery (subject to the appropriate assessments by the cardiac surgery staff in the immediate postoperative period). Antibiotic prophylaxis is always recommended in the event of dental work or “invasive” tests as a preventive measure against bacterial infections that can attack the repaired or replaced valve and the heart as a whole. Before instrumental diagnostic investigations (see Nuclear Magnetic Resonance), the operator will be notified of the presence of a mechanical prosthesis made of a metal alloy whose stability is affected by the machinery.

How long is the mitral valve replacement guaranteed for?

In some patients mechanical valves have worked without creating problems for over 20 years. Thanks to the material they are made of, they are more resistant to functional stress: opening/closing with each heartbeat.