Cardiovascular System
No description yet. This curated deck is ready for daily study.
Card preview (24)
Layers of the heart
Pericardium- protective outer sac layer, pericardial fluid (2 layers) Epicardium- visceral layer of serous pericardium Myocardium- middle layer, largest portion of heart wall, contains contractile fibres/conduction system/blood supply, site of MI Endocardium- innermost layer, smooth muscle, lines valves/ inner chambers of heart
Where is the tricuspid valve?
Right atrioventricular valve
Mitral valve location?
Left atrioventricular valve
Electrical pathway of heart
SA node- AV node- bundle of his- bundle branches- purkinje fibres
What heart sounds are you listening for ?
Lub, dub Lub= atrioventricular valve closing Dub= semilunar valve closing
Stroke volume?
Volume of blood pumped by each ventricle in 1 contraction (Approx 70ml)
Cardiac output
Amount of blood pumped out of the heart in one minute Stroke volume X Heart rate
Aetiology/ causes of cardiovascular conditions
Genetics Age Smoking Exercise Drug/alcohol use Hypertension Stress Type 2 diabetes MI/ ischaemia Chest trauma/ injury Infection
Atherosclerosis
Build up of plaque/fat/lipids in arteries (atheroma) Reduced blood flow Harden over time, pierce artery wall and reduce elasticity, scar tissue formed Increases blood pressure Possible plaque rupture/thrombosis
Consequences of atherosclerosis
Ischaemia due to narrowed blood vessel Complete occlusion= infarction Blood vessels rupture
Congestive heart failure
Later stage of heart failure- weak pump function of ventricles due to thickening/smaller filling capacity (Congestion of fluid in body due to poor circulation)
Preload
Volume of blood in ventricles at the end of diastole
After load
Resistance the left ventricle must overcome to circulate blood
Symptoms of heart failure
Peripheral oedema/ swelling in extremities SOB Chest pain Dizziness, fatigue Heart palpitations Dry hacking cough
Cardiac output equation
Stroke volume X heart rate
Blood pressure equation
Cardiac output X systemic vascular resistance
Left sided ventricular failure vs right
Left: -pulmonary oedema -inability for heart to pump out all oxygenated blood from lungs -air mixes with plasma forming white frothy foam Right: -peripheral oedema in legs/ankles/ -build up of fluid in systemic circulation
Consequences of LVF
Cyanosis SOB/ DIB, Rhonda, wheeze, resp distress Coughing white/pink sputum Jugular vein distension Infection Ischaemia Chest pain Confusion High bp/tachycardia (compensatory) Orthopnoea
Causes of heart failure
Infection Chest trauma MI/ ischaemia Cardiomyopathy (disease of heart muscle) Pulmonary disease Tricuspid/pulmonary valve disease
Heart failure medications
Diuretics- encourage fluid drainage (oedema), reduces hypertension Ace inhibitors- lower bp, reduce strain on heart
Ischaemic heart disease + symptoms
-Reduced blood supply to heart -caused by atherosclerosis of coronary arteries -prolonged ischaemia= necrosis, MI -increased lactic acid in blood from anaerobic respiration of ischaemic tissue Symptoms: Left shoulder/arm pain, angina
Cardiomyopathy
-disease of myocardium (muscle layer of heart), weakens, unable to pump efficiently
Types of cardiomyopathy
-dilated -hypertrophic -arrythmogenic right ventricular dysplasia -restrictive cardiomyopathy (Differ on How the heart muscle is damaged)
Cardiomyopathy leads to…?
Irregular heart beat Heart failure Heart valve issues