problems with the cardiovascular system

• CARDIOBASCULAR DISEASES:

  1. stroke
  2. arrhythmias
  3. coronary heart disease
  4. myocardial infarction
  5. thrombosis
  6. hypertension
  7. heart failure
  8. vascular disease
• PRIMARY HYPERTENSION

  • "of UNknown medical cause"
  • likely contributing factors:

  1. genetic predisposition
  2. high alcohol consumption
  3. sedentary lifestyle
  4. obesity
  5. diabetes
  6. intrauterine environment
• SECONDARY HYPERTENSION

  • "of known medical cause"
  • EG. CHRONIC KIDNEY DISEASE- decreased Na+ excretion, fluid retention and increased RAAS activity
  • EG ENDOCRINE DISORDER- diabetes + cushings syndrome
  • EG PHEOCHROMOCYTOMA (adrenal tumour)- increased catechloamide production
• HYPERTENSION TREATMENT

  • thiazide diuretics= inhibits renal Na+ reabsorption to increase water loss in urine --> decreased Venus return EDV --> decreased CO
  • Ca2+ channel blockers = inhibit Ca2+ entry in cardiac and vascular muscle cells --> decreased contractibility --> decreased CO
  • RAAS inhibition (ACE inhibitor/ Arbs) --> decreased Na+ and H2O absorption and decreased vasoconstriction --> decreased CO
• ARTHEROSCLEOROSIS

  1. triggering factors = endothelial damage (BP, smoking, diabetes) and High LDL cholesterol leads to plaque formation
  2. leads to plaque formation--> narrow lumen
  3. narrow vessels restrict blood flow and increase likelihood of thromboembolism
  4. could lead to stroke, vascular dementia, coronary heart disease

  • TREATMENT= statins (inhibit cholesterol synthesis, decrease LDL)
• THROMBOSIS

  • blood clots can form in the circulation, especially wire static/ low blood flow
  • TREATMENT = anticoagulants (warfarin) and anti-platelet drugs (aspirin)
• PATHOGENESIS- myocardial infarction

  1. artheroscleosis of coronary artery- restricts myocardial blood flow --> chest pain angina
  2. atherothrombosis (plaque rupture/ embolism) --> no myocardial blood flow
  3. myocardial infarction- muscle distal to blockage starts to die

  • left anterior descending coronary artery most commonly affected
  • TREATMENT:

  1. percutaneous coronary intervention: minimally invasive operation using a catheter to insert a stent and reopen the blocked artery
  2. thrombolytics: break up clot
• VALVULAR DISEASE

  STENOSIS

  • thick/ stiff valves fail to open properly
  • increases after load reducing ejection
  • rheumatic fever is a common cause, with symptoms appearing years after infection
  • leads to LV hypertrophy and eventually failure

  REGURGITATION

  • valves fail to close properly
  • results in back flow of blood
  • reduces stroke volume and cardiac output