Cardiac pathologies Flashcards
Define Aetiology
Is the study of the cause of disease or condition
Define pathogenesis
Refers to the progression of the disease & mechanism of disease development
Define morphological changes
Refers to structural changes or adaptations that are a characteristic of the disease e.g., at the molecular or cellular level
Define clinical manifestations
Refers to how the disease presents itself, through testing, signs and symptoms.
Signs are visible/ audible e.g., heart murmur or oedema
A symptom cannot be seen e.g., chest pain
Define clinical course
Clinical course is the clinical course of the patient, refers to the steps in the treatment, their pathway & interventions
Define diagnosis & prognosis
Diagnosis: relies on tests, family history, symptoms etc to draw an overall conclusion, that reflects all the information collected on the disease
Prognosis: the prediction of the patients future with the disease e.g., lifespan, looks at the likely outcome of the situation
Define incidence & prevalence
Incidence: The number of new cases e.g., per annum, referred to in the thousands/ hundred thousands
Prevalence: The number of existing cases of disease, how many people in the population are already living with the disease
Define epidemiology
Refers to the study of incidence, distribution, and possible control of disease or determinants of health, it looks at disease within a population
What are the 6 main types of HD?
- Ischaemic HD (CHD)
- Valvular HD
- Congenital HD
- Myocardial HD
- Pericardial HD
- Hypertensive HD
Describe ischaemic HD
Also known as coronary HD, It is the most common HD & occurs in large/medium coronary arteries
Pathogenesis is atherosclerosis, arteries have become narrowed, blood flow restricted, a thrombus may break off & embolise
IHD creates less supply to the heart & increased demand
Describe the importance of supply & demand
Needs to be in balance to allow heart to pump effectively
Supply is determined by HR, vascular tone (dilation/constriction), disease present, narrowed/non-responsive, anaemia as not enough O2 in the blood.
Demand is determined by HR; increased HR creates an increased demand for O2. Preload, afterload, contractility also influences demand.
Describe the modifiable, non-modifiable factors & treatment of IHD
MF: Lifestyle changes e.g., diet, weight, smoking, excessive drinking, HBP, diabetes & high cholesterol
NMF: age, genetics, gender
Treatment: most effective treatments are lifestyle changes (diet & exercise), medications of statins or surgery’s such as bypasses
Describe valvular heart disease
Refers to disease of the valves (AV, TV, PV, MV), it can be acquired or congenital, valve may become damaged/infected
Valve may stiffen known as stenosis
Valve may leak and cause regurgitation of blood, known as an incompetent valve as it does not assist with the unidirectional flow of blood
Prolapsed valve refers to where a leaflet bulges backwards, leaflets may be too weak, stretchy, as a result blood flows backwards
Describe congenital HD
Refers to people born with a defective heart due to a abnormal embryonic development, genetic changes or environmental factors during gestation period
Describe the types of defect and their effect on the heart in CHD
- Septal defects: a hole in the septum, chambers are not separated properly, can have ASD or VSD
(atrial & ventricle defect)
affects overall blood flow - Obstructive defects: Blockage/narrowing of BV’s or valves that reduce blood flow, e.g., Coarctation of aorta (narrowing) or pulmonary stenosis
- PDA: opening between the aorta & pulmonary artery t(he ductus arteriosus) remains open after birth creating abnormal blood flow,
Describe hypertensive disease
HHD is caused by hypertension, having a BP over 140/90, this results in an increased afterload, this causes an increased demand, but less supply, It can cause hypertrophy of BV’s and increased risk of HD
Describe myocardial disease (ischaemic & non-ischaemic)
MHD is a disease of the myocardium, the middle muscular layer involved in pumping action of the heart, disease can weaken of damage the myocardium
1. Ischaemic MHD: caused by lack of blood to myocardium as coronary arteries have become blocked/narrowed, not enough O2 is recieved creating symptoms such as SOB, Angina
This could lead to a heart attack
2. non-ischaemic MHD: types of cardiomyopathy which involves thickening, stiffening or weakening of myocardium, affecting the pumping of blood
Describe cardiomyopathy in MHD
3 types involved in MHD
1. Dilated CM: Heart muscle becomes weakened & stretched, affecting it’s efficiency as a pump
2. Restrictive CM: the walls of the heart become rigid impairing the ability of the heart to fill with blood
3. Hypertophic CM: Myocardium becomes increasingly thick which can obstruct blood flow & cause arrythmias
Describe myocarditis in MHD
Myocarditis is the inflammation of the myocardium
Cause: viruses, infections, autoimmune conditions
Effects: often weakens the heart muscle affecting heart’s efficiency as a pump, can often lead to heart failure or arrthymias
Describe the symptoms, diagnosis & treatment of MHD
Symptoms: angina, SOB, odema, fatigue & dizziness
Diagnosis: ECGS, echos, MRI’s & blood tests
Treatment: medications e.g., beta-blockers, lifestyle changes (diet/exercise) & surgical interventions (bypass)
Describe pericardial HD
This is disease of the pericardium, the outer protective layer of the heart, consisting of the parietal, visceral & fibrous pericardium
Contains normal fluid of 10ml, Pericardium anchors the heart in place allowing it to contract smoothly in the chest
Describe pericardial effusion
Where there is an excess of pericardial fluid in the pericardial sac
Cause: trauma, infection or cancer
Symptoms: often asymptomatic, SOB
Treatment: draining of pericardial fluid via pericardiocentesis & medication to treat underlying cause
Build-up of excessive fluid creates risk of cardiac tamponade
Describe cardiac tamponade
A life-threatening condition where the heart becomes compressed by the build-up of fluid, RA is at risk of collapsing in on itself, Heart cannot pump effectively
Symptoms: Hypotension, SOB, tachy & fainting
Cause: Cancer, trauma, infection & PE
Treatment: the removal of the fluid through a procedure called pericardiocentesis
If left to long may result in a cardiac arrest
Describe constrictive pericarditis
A rare chronic condition where the pericardium becomes thickened & fibrous which restricts normal movement of the heart
symptoms include: SOB, fatigue and swelling in limbs
Caused: by repeated pericarditis, TB or radiation
Treatment: involves anti-inflammatory drugs or removal or pericardium in SEVERE cases
Describe the diagnosis and treatment of PHD
PHD often diagnosed using imaging techniques e.g., echo,
Treatment: varies on type of PHD, can include anti-inflammatory medication, antibiotics or drainage procedures (pericardiocentesis)
What are the 4 main principles of cardiac dysfunction
Pump- how effectively the heart acts as a pump, if heart muscle becomes weak/inert, heart is unable to contract properly & therefore empty properly
Obstruction: if the vessels have become narrowed, stenotic or blocked completely
Regurgitation/incompetence of the valves, if blood begins to flow backwards or valves become leaky
Conduction: dysfunction in electrical events result in a mechanical consequence, it could be normal or harmful e.g., may cause fibrillation etc, it is an electrical abnormality
