Understand Heart Attack (Myocardial Infarction), Causes, Mechanism, Symptomsheart diseases 6/21/2010
Heart attack or Myocardial Infarction (Mayocardium = Heart Muscles/wall, Infarction = Death) is a term used to define death of a part of the heart wall due to blockage of blood flow. When blood flow is partially blocked it results in myocardial ischemia which manifests clinically as Angina. Prolong Myocardial Ischemia may lead Mayocardial Infarction.
What is Heart Normal function?
this is human heart.
Heart function is to Pump blood. and make sure that blood reaches to all parts of body according to their needs. Blood contains oxygen, nutrients which provide energy, and blood also removes waste metarials from the site of formation and take these wastes to the site of excretion (kidneys).
Look at the diagram.
Deoxygenated (poor blood /used blood) from all parts of the body reaches to the right atrium of heart through superior and inferior vena cavae. Then right attrium contracts and blood reaches to right ventricle then right ventricle contracts and blood is pushed in to the pulmonary arteries. pulmonary arteries take the blood to the lungs. In the lungs blood is purified and oxygenated . The purified and reusable blood then reaches to left atrium through pulmonary veins. Now the left atrium contract and blood reaches to left ventricle and then left ventricle contracts and blood is pushed in to aorta.
Aorta supplies purified oxygenated blood to all parts of the body from head to feet. and the used blood from head and upper limbs reaches again to the heart via superior vena cava and from rest of the body via inferior vena cava and pumped again
arrows show the movement of blood in heart chambers
So i hope now u have understood the function of heart.
What is Heart Attack?
To pump blood Heart chambers contracts.
It is obvious that left ventricle needs more force of contraction because it has to push the blood to all parts of the body. right ventricles only supplies lungs for purification purposes. Therefore, the left ventricular wall is thicker as compared to right ventricular wall.
Heart attack occurs when blood supply to heart impairs. This may occur as a result of blockage of a branch of coronary artery by an atheroseclerotic lesion or embolus or it may also occur as a result of coronary vasospasm. The symptoms include, chest pain which may radiate to left arm, shoulder and lower jaw. sweating, vomiting , breathlessness and syncope. Patient must be taken to the hospital as soon as possible. It is important that the obstruction must be removed as soon as possible to prevent death of the ischemic cardiac muscle.
(Note: in medical term the condition in which heart fails to pump blood adequately is known as heart failure. In heart failure cardiac output decreases and becomes insufficient, heart attack more appropriately is a term used to define myocardial infarction, it is a condition in which blood supply to heart muscle diminishes which results in death of the ischemic part of the cardiac muscle, which then heals by scaring. Myocardial infarction or heart attack is a cause of heart failure).
what may be probable reasons behind this.
Causes of Heart Attack.
- coronary arteries blockage :
we know that coronary arteries supplies blood to heart muscles. if because of any reason coronary arteries block or become narrow heart muscles exhaust and fail to pump blood. factor that can block heart coronary arteries include:
- Blood Clot. normally blood remain in liquid form in the vessels various factors don't allow the blood to clot. but some times blood clot may form and enter the cronary arteries and may cause their obstruction.
- Atherosclerotic plaques: Atherosclerotic plaques are formed by deposition of fats in the walls of vessels. when atheroseclerotic plaques form in coronary artery it narrows it lumen or may cause obstruction. which result in decreased or diminished blood supply to heart wall musculature.
2. Hypertension: Increased blood pressure , whatever the reason behind causes heart to work more
and heart contract more forcefully to pump blood with high pressure so High BP may cause weakness
of heart muscles and cause heart complications.
3. Diabetes (sugar) .
4. Obesity (fat body)
5. kidney problems.
These are the common conditions which may lead to heart failure
Heart attack symptoms
Reducing the risk of heart attack.
In a nutshell , maintaining proper diet that is a diet which is balance and with low fat content and regular exercise greatly reduces the probability of heart attack. remain healthy and adopt healthy habits, avoid smoking, avoid oily food, avoid much alcohol, avoid non prescribed drugs.