How does our heart work?

Il Heart is the pivot of the blood circulationa muscle that supplies blood to every part of our body. Blood carries oxygen and other important nutrients that all of our organs need to stay healthy and function properly. But how exactly does it work?

We talked about it with Dr. Damiano Regazzoli Lancinicardiologist at the outpatient clinic Humanity Medical Care Premuda in Milan.

What is the heart for?

The heart is a pump whose main function is to carry blood rich in oxygen to cells, tissues and organs, in order to nourish them, and to receive the blood full of carbon dioxide to be sent to the lungs where it is exchanged with oxygen.

Oxygenated blood travels through the body to organs and tissues, carrying nourishment throughout the body.

How is the heart made?

The heart is located in the chest (protected by the sternum), slightly to the left and resting on the diaphragm (the muscle that separates the chest and abdomen and allows breathing). It is roughly the size of a fist and is made up of three layers of fabric: the pericardium, a serous sac that surrounds and protects it; L’epicardio; il myocardium, the “muscle” of the heart; L’endocardiowhich forms the inner walls of the heart.

There are four chambers that make up the heart: two on the left and two on the right. The upper rooms are the atri; the lower ones are i ventricles. Il right ventricle receives the venous bloodtherefore not yet oxygenated, but loaded with carbon dioxide from the right atrium and contracting pushes it towards the lungs through thepulmonary artery.

In the lungs the blood fills with oxygen that comes from the air we breathe and then returns to the heart. The left ventricle receives oxygenated blood from the left atrium and contracting pushes it intoaorta through the aortic valve so as to reach the rest of the body and deliver oxygen and nutrients to cells and tissues.

Separating the heart chambers are four valves (aortic, mitral, pulmonary and tricuspid valves), which control the unidirectionality of blood flow and act like doors that open and close with each heartbeat.

To provide for the nutrient needs of the heart itself, there are three arteries (called coronary arteries) which supply the heart muscle in all its portions.

How fast does the heart beat?

The speed of the heart beat (called heart rate) depends on the body’s need for oxygen-rich blood. At rest we consider physiological a frequency between 50 and 100 beats per minute, which can increase greatly with physical exercise. In fact, during physical activity the heart, which at rest supplies about 5 liters of oxygenated blood per minute, can increase its cardiac output up to 20-30 liters of blood per minute, mostly with an increase in heart rate.

How is the heartbeat measured?

Heart rate measurement is simple and can be done by simply palpating an artery, usually in the wrist or carotid artery (on the sides of the neck).

Blood pressure monitors can also reliably detect heart rate, as can many smart watches or other digital devices nowadays.

During the Cardiological Visit, the heart rate analysis is carried out through theelectrocardiogram.

In which cases of heartbeat alterations should we consult a Cardiologist?

The resting heart rate is considered normal to be between 50 and 100 beats per minute, although in most people this is between 55 and 75 beats per minute. Heart rhythm is considered abnormal if the rate is adequately fast (in this case we speak of tachycardia), slow (bradycardia) or irregular (arrhythmia).

It is uncommon for heart rhythm disturbances to occur without symptomsalthough in some patients arrhythmias do not lead to significant changes in clinical status. In most cases, tachycardias manifest with the onset of palpitations or palpitations, of different duration and intensity; conversely, bradycardia can lead to loss of consciousness (syncope).

In case of the onset of the above symptoms, a Cardiological evaluation is indicated, usually after a preliminary assessment by the General Practitioner who will decide the timing and methods of the visit.

The Cardiological visit for the first evaluation of arrhythmia includes an accurate anamnestic collection (clinical and general data of the patient and information about the symptoms), an objective examination (the visit proper) and a electrocardiogram. In this way it is possible to quickly exclude the most acute and potentially dangerous problems (such as atrial fibrillation or atrial flutter, as well as atrioventricular blocks).

Subsequent evaluations may include a echocardiogram (ultrasound of the heart to evaluate the morphology and function of the heart muscle and heart valves), a dynamic ECG according to Holter (a small device that you wear to record your heart rate for 24 or 48 hours), the stress test (exercise during electrocardiographic monitoring) and a series of blood tests (mainly aimed at electrolytes and thyroid function).

Although the arrhythmias usually carry a modest risk (apart from the person’s significant anxiety and negative feelings), some have potential short- or long-term consequences. For these cases it may be necessary, albeit infrequently, to introduce a specific drug therapy or a interventional treatment: after one electrophysiological evaluationwill be implanted a pacemaker (a small device that fits into the chest to prevent slow arrhythmias) or performed a transcatheter ablation (the abolition of arrhythmia through a small catheter advanced from the venous route).

Humanitas numbers

• 12.000.000
  Visit

• 1.000.000
  patients

• 7.300
  professionals

• 190.000
  hospitalizations

• 12.000
  medici