Cardiovascular Disease Epidemiology
Leading cause of death for both men and women
- 630,000 deaths/year (1 in every 4 deaths)
- Coronary heart disease (aka coronary artery disease (CAD), ischemic heart disease (IHD)): 366,000 deaths/year
- 1 heart attack in the US every 40 seconds
Risk factors: high blood pressure, high LDL cholesterol, smoking
Atherosclerotic Cardiovascular Disease (ASCVD)
Terminology: coronary heart disease (CHD), coronary artery disease (CAD), ischemic heart disease (IHD) - All the acronyms that represent the same thing
Imbalance of myocardial oxygen supply and demand (atherosclerosis of coronary arteries)
-the building up of plaque to clog an artery
ASCVD (Known for exam*****)
- Acute coronary syndromes (ACS)
- History of MI
- Stable or unstable angina
- Coronary ot other arterial revascularization
- Stroke/TIA
- Peripheral artery disease (atherosclerotic origin)
ASCVD Causative Risk Factors (High correlation between the condition and ASCVD)
- cigarette smoking
- hypertension
- low high-density lipoprotein cholesterol (<40mg/dl)
- high total and low-density lipoprotein cholesterol
- type 1 and type 2 diabetes mellitus
ASCVD Predisposing Risk Factors
- obesity/overweight
- physical activity
- family history of premature coronary heart disease (in male, first degree relative <55 years; in females, first-degree relative <65 years)
- age (men>=45 years; women >=55 years
- insulin resistance
Angina
-intermittent chest pain caused by temporary oxygen insufficiency and myocardial ischemia
Angina (Stable)
- caused with plaque
- occurs with increased workload, exercise, or stress
- Oxygen supply can’t be increased to compensate for increase demand
- Typically described as diffuse, heavy pressure, or deep squeezing
- May or may not radiate down arm or to jaw
- Usually relieved with rest or nitroglycerin
- β-blockers, calcium channel blockers, and aspirin
Angina (Unstable)
- caused with plaque
- may occur with exertion, or at rest
- Typically more intense and can last longer than stable
- At higher risk of MI
- May or may not be relieved by rest
- Can use same medications to treat
Angina (Variant)
- Occurs at rest; typically to younger patients
- Caused by coronary vasospasm
- Patient usually younger
- Can use same medications to treat
- Ex: Leg spasm
Myocardial Infarction (MI)
-Commonly called a ‘heart attack’
- Myocardial cell death and necrosis due to local, severe, or prolonged ischemia
- **Caused by coronary artery occlusion
Myocardial Infarction Signs
- rapid, weak heart rate
- ECG changes (ie Q waves, ST segment elevation, T-wave inversion)
- rise in troponin
Myocardial Infarction Symptoms
- Moderate to severe angina not relieved by rest or nitroglycerin (may last several hours; radiate to arm(s), next, jaw, shoulder, or back)
- shortness of breath
- nausea, vomiting, or both
- sweating
- light-headedness or dizziness
- fainting
Heart Failure
-Inability to pump sufficient blood to meet the metabolic needs of the body
-Systolic dysfunction
Reduced LV ejection fraction (LVEF) < 40%
-Diastolic dysfunction Normal LVEF (55-70%) Stiff LV wall, unable to relax during diastole (volume of what it pumps out is less)
Heart Failure (HF) - Compensatory Responses - Cardiac Dilation
- Residual blood accumulated in the ventricle
- Causes stretching of myocardial fibers and dilation of ventricle
Heart Failure (HF) - Compensatory Responses - Cardiac Hypertrophy
- An adaptation to the increase diastolic volume
- Causes increased ventricular muscle mass and wall thickness
Heart Failure (HF) - Compensatory Responses - Activation of sympathetic nervous system
- Release of norepinephrine and other catecholamines in response to reduced CV output and tissue perfusion
- Causes increased HR and contractility to maintain normal CV output
Heart Failure (HF) - Compensatory Responses - Stimulation of renin- angiotensin-aldosterone system (RAAS)
-Due to reduced renal perfusion through sympathetic nervous system activation
-Causes aldosterone release sodium and water retention increased
venous pooling of blood due to failing ventricle
Heart Failure (HF) Signs***
- Tachycardia
- S3 gallop
- LV hypertrophy
- Rales or crackles
- EF <40%
- Weight gain
- Increase blood urea nitrogen (BUN)
- jugular venous distension
- hepatomegaly
- hepatojugular reflex
Heart Failure (HF) Symptoms
- shortness of breath
- dyspnea on exertion
- orthopnea
- paroxysmal nocturnal dyspnea
- peripheral edema
- cough
- weakness
- fatigue
Hypertension (HTN)
-Elevated SBP > 140 mmHg, DBP > 90 mmHg, or both
90% of patients have idiopathic HTN (idipathic = we don’t know why you have hypertension)
-Secondary causes (10%): renal disease, adrenal disorders (primary aldosteronism, Cushing’s Syndrome, or pheochromocytoma), or pregnancy
Lipid Disorders
Terminology: Hyperlipidemia (HLD), Dyslipidemia, hypercholesterolemia, “high cholesterol”
Triglycerides (TG)
- Consist of FFA and glycerol, used for stored energy
- Levels above 500 can increase risk of pancreatitis
- Dependent on dietary fat
Lipoproteins
- LDL is the “bad cholesterol” lodges in arterial walls and stimulates atherosclerotic plaque development
- HDL is the “good cholesterol” removes cholesterol from arterial wall, takes to liver for disposal
- Lipoprotein (a) similar to LDL, genetically determined, higher tendency to form clots
Apolipoproteins
- Play major role in binding, solubilizing, and transport of lipids
- Include Apo B and A1 (as examples)
