CVS Flashcards
causes of primary vs secondary hypertension
- Primary (essential) hypertension (90-95% of cases)
- Multitude of genetic and environmental factors
- Modifiable risk factors
- Stress, obesity, smoking, physical activity, heavy salt consumption
- Secondary Hypertension (5-10% of cases)
- Renal: Renal Artery Stenosis
- Endocrine: Cushing’s syndrome, pheochromocytoma
- Neurological: Increased intracranial pressure
- Aortic: Aortic coarctation, atherosclerotic rigidity of
aorta - Labile: psychogenic, stress-related
modifiable and non-modifiable risk factors of atherosclerosis
- Constitutional (Non-modifiable) Risk Factors
- Age
- Gender (Male)
- Family history
- Genetics
- Modifiable Risk Factors
- Hyperlipidaemia
- Hypertension
- Diabetes
- Smoking
consequences of atherosclerosis
- Ischaemia: Vessel thickening → Narrowed lumen → Poor tissue perfusion → Ischaemia
- Aneurysm formation: Loss of elasticity → Predisposition to aneurysm formation, rupture** and haemorrhage
- Endothelial changes → Predisposition to thrombosis
- Acute plaque change
- Rupture/fissuring
- Erosion/ulceration
- Haemorrhage
- Can lead to
- MI
- Cerebral Infarction
- Aortic aneurysm
- Peripheral vascular disease
causes of ischaemic heart disease
- Atherosclerosis of coronary vessels (90-95%)
- Embolism
differences between stable angina, prinzmetal (variant) angina, unstable angina
- Stable Angina
- Most common and typical form
- Relieved by rest or vasodilators (e.g Glyceryl trinitrate)
Prinzmetal (Variant) Angina
- Uncommon form of episodial myocardial ischaemia
- Due to coronary arterial spasm; underlying mechanism unknown
- Responds to vasodilators
- Unstable Angina
- Increasingly frequent pain, prolonged duration (>20 minutes)
- Occurs at lower levels of activity or at rest
- Increased risk of MI
- Also serves as a warning that an acute MI is imminent
- Leads to severe but transient reductions in coronary blood flow
most common locations of myocardial infarction
- Left anterior descending coronary artery: 40-50%
- Right coronary artery: 30-40%
- Left circumflex coronary artery: 15-20%
myocardial infarction symptoms and diagnosis
- Symptoms
- Severe, crushing central chest pain
- Rapid weak pulse, profuse sweating (diaphoresis)
Diagnosis:
- ECG Changes
- Transmural infarcts:
-ST elevation MI (STEMI)
- Subendocardial infarcts:
- non-ST elevation MI (non-STEMI)
- Elevated cardiac enzyme levels
- Troponin I & T
- Creatine Kinase (CK-MB)
morphology and histology of myocardial infarction
Morphology:
12-24 hours:Pale with botchy discolouration
3-10 days: Hyperaemic border around yellow area
6-8 weeks: Fibrous scar - white
Histology:
12-24 hours: Infarcted muscle brightly eosinophilic, loss of nucleus, intercellular oedema
24-72 hours: Neutrophil infiltration
3-10 days: Granulation tissue appears
6-8 weeks: Dense collagenous scar (fibrous)
complications of myocardial infarction
- Ventricles
- Left Ventricular Failure → Congestive Heart Failure
- Ruptured myocardium
- Usually 2 to 4 days post MI
- Conduction system
- Arrythimas → Sudden cardiac death
cause of aortic stenosis
Aortic Valve Calcification
- age associated degeneration of aortic valve
- Most common of all valvular abnormalities
mitral regurgitation cause
Mitral Valve Prolapse
- Young women (7:1 F:M ratio)
- Cause is usually unknown
two types of infective endocarditis and the organisms that cause them
- Subacute endocarditis
- Streptococcus viridans – 75% of cases (normal flora of oral cavity)
- Insidious infection of abnormal heart valves (includes congenital defects)
- Acute endocarditis
- S. aureus (IV drug abusers)
- Highly virulent pathogenic organisms directly invade normal heart valves valve and cause rapid destruction
5 types of pericarditis and their causes
- Serous Pericarditis
- Causes: Non-infectious inflammatory diseases (immune-mediated, uremic, tumours)
- Fibrinous Pericarditis (can overlap with serous)
- Causes: post-myocardial infarction, rheumatic heart disease
- Suppurative (purulent) Pericarditis
- Causes: infections
- Haemorrhagic Pericarditis
- Causes: Direct spread or malignant metastases
- Caseous Pericarditis
- Causes: tuberculosis
clinical features of pericarditis
- Sharp, more left-sided pain
- Reduced when leaning toward, worsens when lying down
- Radiation to shoulder tip, neck or jaw
- Worse on lying down
- Pericardial rub in 50% of patients
ecg signs of atrial fibrillation
No P waves, Fibrillatory baselines (f waves), Irregularly irregular R-R intervals
associations of atrial fibrillation
Associated with thyrotoxicosis, mitral valve disease, cardiac failure, ischaemic heart disease, hypertension, chronic lung disease, aging
definition of heart failure
Heart failure is a clinical syndrome with current or prior
- Symptoms and or signs caused by a structural and/or functional cardiac abnormality (EF < 50%, moderate to severe ventricular hypertrophy etc)
- and corroborated by at least one of the following
- Elevated natriuretic peptide levels
- Objective evidence of cardiogenic pulmonary or systemic congestion by diagnostic modalities such as imaging
heart failure diagnostic results
- Chest X-Ray
- Peri-hilar reticulo-nodular shadowing
- Upper lobe diversion
- Effusion
- ECG
- Different ECG patterns
- Lab tests & Biomarkers
- BNP or NT-proBNP
what is the framingham criteria for heart failure diagnosis
Simultaneous presence of at least 2 major criteria or 1 major criteria in conjunction with 2 minor criteria
Major Criteria:
Paroxysmal nocturnal dyspnea
Neck vein distention
S3 gallop
Hepatojugular reflex
Minor Criteria:
Bilateral ankle edema
Nocturnal cough
Dyspnea on ordinary exertion
Tachycardia
compensatory mechanisms of heart failure
-Compensatory measures in response to increased cardiac workload or impaired cardiac function
- Hypertrophy
- Increased sympathetic stimulation
- Frank-Starling mechanism: increased EDV dilates heart and causes increased cardiac myofiber stretching leading to increased CO
- Increased stimulation of RAAS
causes of left sided heart failure
- Volume overload
- Valvular disease (aortic & mitral insufficiency)
- Pressure overload
- Systemic hypertension
- Valvular disease (aortic stenosis)
- Myocardial defect
- Ischaemic heart disease (myocardial infarction)
- Restricted filling
- Pericardial effusion
complications of left sided heart failure
- Backward failure
- Pulmonary venous hypertension
- Pulmonary oedema (with associated symptoms of dyspnea, orthopnea, paroxysmal nocturnal dyspnea)
- Forward failure
- Decreased cardiac output & hypotension
causes of right sided heart failure
Left-sided heart failure
- Most common cause of right-sided heart failure
- Due to resultant pulmonary hypertension which eventually places a burden on the right heart
complications of right sided heart failure
- Congestive hepatosplenomegaly
- Effusions (ascites, pleural effusion)
- Peripheral subcutaneous oedema
- Venous congestion & hypoxia of organs (e.g. chronic passive congestion of liver)
- hepatomegaly and splenomegaly
complications of congenital heart disease
- L / R Ventricular hypertrophy & subsequent HF
- Pulmonary hypertension
- Shunt reversal
- In left to right shunt, problem of Eisenmenger Syndrome arises when there is shunt reversal
4 cardinal features of tetralogy of fallot
- Pulmonary stenosis
- Right ventricular hypertrophy
- Ventricular septal defect (VSD)
- Overriding aorta
