Cardiology Flashcards
Angina
term which is used to describe symptomatic chest pain which is due to myocardial ischaemia.
Angina pathophysiology
- Coronary Circulation allows blood filling in diastole
- Atherosclerosis over time →Coronary arteries occluded → less blood flow
- Areas of myocardium are ischaemic→ especially during exertion
- To counteract , body increases sympathetic Stimulation → increase HR → Increase force of contraction
- O2 demand increases even more
Angina occurs as blood supply can’t meet demand
Atherosclerosis process
Step 1 - endothelial dysfunction
Endothelial injury causes a local inflammatory response → accumulation of LDL → become oxidised by waste products creating reactive oxygen species.
Step 2 - plaque formation
Endothelial cells attract macrophages → phagocytose the LDLs swelling to become foam cells and ‘fatty streaks’.
Step 3 - plaque rupture
Continued inflammation triggers smooth muscle cell migration → forms a fibrous cap + fatty streaks → develops into an atheroma. It causes vessel narrowing and leads to angina.
Stable Angina
Full occlusion
i) Constricting discomfort in the front of the chest/neck/shoulders/arms
ii) It is precipitated by physical exertion
iii) Relieved by rest or GTN spray in 5 minutes
Unstable Angina
Chest pain that occurs at rest, Partial occlusion
– due to rupture of plaque →incomplete occlusion of coronary artery
– ST-segment depression
Prinzmetal’s angina = ST elevation. Treated with CCB
Angina diagnosis
CT Coronary Angiography
- Myocardial perfusion imaging (if patient has renal impairment)
- ECG
- Physical examination
Angina Treatment
Lifestyle management….
- GTN Spray
Secondary:
- Aspirin
- Statin
- Beta Blocker (bisoprolol) - Give CCB for Asmatics
- Ca2+ channel blocker ( amlodipine)
- ACE-I (for diabetic & hypertensive Patients)
- Isosorbide Mononitrate (long acting nitrate)
Surgical Intervention : (Stable)
→ PCI with coronary angioplasty
→ Coronary Artery Bypass Graft (CABG)
Revascularisation (PCI)
Percutaneous Coronary Intervention (PCI) involves insertion of a stent into a coronary artery to improve blood flow.
Revascularisation (CABG)
Coronary artery bypass grafting aims to restore flow within a coronary vessel
Angina Risk factors (Modifiable & Non- Modifiable)
-> Modifiable risk factors: High cholesterol Hypertension Smoking Diabetes Obesity -> Non-modifiable risk factors: Age Family history Male sex Premature menopause
Myocardial Infarction
irreversible death of cardiac myocytes, which occurs due to ischaemia
MI Cause
– It is due to the rupture of a plaque which leads thrombosis and complete / Partial occlusion of the artery
MI risk factors
Non - Modifiable= Age, FH, Male
Modifiable = Smoking, Alcohol, Poor diet, low exercise
Co- morbidities = Diabetes, Hypertension, CHD
MI symptoms
– Acute crushing central chest pain that comes on rest – Pain radiates – Sweaty and clammy – Nausea, Vomiting and epigastric pain - Dyspnoea
MI Diagnosis
- ECG: ST elevation or New left bundle branch block = STEMI
- No ST elevation = Do Troponin blood tests
- Raised troponin levels & ST depression, T wave inversion = NSTEMI
- Normal troponin levels & ST depression = Unstable Angina
STEMI
caused by a complete and persistent blockage of the artery resulting in myocardial necrosis
NSTEMI
NSTEMI and unstable angina a partial or intermittent blockage of the artery occurs, which usually results in myocardial necrosis in NSTEMI but not in unstable angina.
STEMI management
M = Morphine
M = Metoclopramide
O = Oxygen
N = Nitrates (IV)
A = Aspirin (300mg)
C = Clopidogrel or Trigalor (contra-ind. for haemorr.)
→ PCI (offered within 2hrs of symptoms)
→ CABG
NSTEMI management
GRACE score
– High risk = coronary angiography (with 96 hrs)
- Low risk = Aspirin with Trigalor
Heart Failure
cardiac output which is inadequate to meet the body’s requirements.
Left ventricular failure features
Causes:
- Pulmonary congestion
- Systemic hypoperfusion (reduced left heart output)
Left ventricular failure Symptoms
– Dyspnoea - Paroxysmal nocturnal dyspnoea - Orthopnoea (breathlessness lying down) - Peripheral oedema – Gives a 3rd heart sound
Right Ventricular failure features
- can occur due to Left heart failure
Causes:
→ venous congestion
→ Pulmonary hypoperfusion (reduced right heart output)
Right Ventricular failure symptoms
– Raised JVP
- Pitting ankle & Pulmonary oedema (bi-basal) and ascites
- Abdo. distension & discomfort
– Hepatosplenomegaly with a smooth “nutmeg” liver which is pulsatile