Heart Attack Flashcards
What is the cause of a heart attack?
Blockage of 1 or more coronary arteries
What does the blockage of the coronary arteries do?
Deprives the heart of oxygen, resulting in chest pain and irreversible heart cell death
An infarction results in _____ of the affected myocardial cells
Death or necrosis
Repair of heart damage after heart attack is by____
By non-contractile scar tissue since mature myocardial cells can’t divide
A major sign of a heart attack is?
PAIN
What does MI treatment involve?
Angioplasty - inserting a balloon to unblock an artery and inserting stents to prevent reblockage
What is a coronary Bypass?
Procedure to bypass a blocked section of a coronary artery and to deliver O2 to the heart
Steps for Diagnosing Angina or Myocardial Infarction?
Getting the history of pain
Other signs and symptoms
Taking vital signs (BP, P, Temp, BPM)
Electrocardiogram
Blood test for cardiac biomarkers
What is an ECG?
A 12 lead ECG is required to diagnose MI and which areas of the heart are involved. This makes it possible to anticipate complications
What does the P wave denote?
Atrial depolarization
What does the QRS wave denote?
Ventricular DEpolarization
What does the T-wave denote?
Ventricular REpolarization
A myocardial infarction may be indicated in an ECG by?
A raised S-T segment in two or more lead tracings
Confirmation of an MI may involve the presence of?
Cardiac Biomarker
What is Ischemic heart disease?
Imbalance between the myocardial blood flow and the metabolic demand of the myocardium
The tunics of the _____are the thickest?
Arteries
Aging deteriorates the layers of tunica causing?
Less elastic and Harder arteries – impeding contractional and dilation
What is atherosclerosis?
Thickening of the arterial wall & reducing lumen due to damage of the tunica intima
Damage to the tunica intima may be caused by?
Bloodborne chemicals
Hypertension
Components of cigarette smoke
Viral or bacterial infections
Risk Factors of atherosclerosis?
Increasing age
Kidney disease
Lack of exercise
High blood cholesterol & Metabolic syndrome
To cause ischemia, the cross-sectional area of the coronary artery lumen must be reduced by more than?
75%
By the time a coronary blockage develops over a time what does the body do?
Multiple collaterals grow and make alternative routes around the blockage creating a ‘Natural Bypass
What is Angina Pectoris?
Is severe pain caused by a fleeting deficiency in blood delivery to the myocardium (lack of oxygen and increased lactic acid stimulate nerve endings)
What can cause Angina?
Blockage of the coronary artery may result in ischemia
When does Angina usually occur?
Stressed or during physical activity when the oxygen requirements of the myocardium are not met
What are defibrillators?
They use electric shock to correct life-threatening heart rhythm, which restarts the heart
Myocardial infarction is a common cause of ?
Heart Failure
A failing heart is still______
Beating
Heart Failure occurs when?
The heart fails to pump sufficient blood to meet the body’s usual needs
Heart failure may involve the left or_________
Right ventricles
Heart failure of one side can lead to_____
The failure of the other
Which ventricle failure occurs first?
The left
What happens when left ventricular failure occurs?
Causes back pressure on the lungs which may result in pulmonary oedema and often causes right ventricular failure
Failure of the right heart, which outputs blood to the pulmonary circulation, causes signs and symptoms in the ________
Systemic system
Anything that impairs blood flow through the lungs can cause congestion in the ________
Pulmonary Artery
Congestion of the pulmonary artery will interfere with _________
Right ventricle emptying leading to right-sided failure
Treatment of Heart Failure and Myocardial Infarction involves importantly pain management why?
Pain stimulates a stress response adrenaline & noradrenaline released à breakdown of glycogen and fat resulting in ↑ glucose & fatty acid in plasma possibility of more injury to the heart muscle
When heart failure occurs CO is?
Decreased
What is preload?
Pressure on the myocardium when heart relaxed
In a compensated HF the renal system will result in?
An increase in heart rate and contractility (cardiac output) and an increase in salt and water retention (blood volume)
What is LVEF?
Measures how much blood the LV pumps out with each contraction
Many patients with heart failure have a normal LVEF as shown by?
Echocardiography
Preserved ejection fraction (HFpEF)– aka?
Diastolic failure, heart contracts properly, but ventricles DO NOT RELAX
Reduced ejection fraction (HFrEF)– also referred to as?
Systolic Failure. Heart muscle does not contract effectively and less blood is ejected
