Cardiology

Pharmacotherapy III

Auscultation

Listening to heart sounds through a stethoscope, valvular abnormalities and cardiac shunts. (Abnormal blood flow) can be detected as murmurs.

Electrocardiography (ECG)

Uses temporary electrodes on the chest and limbs to monitor and document the electrical activity of the heart • Used in the diagnosis and monitoring of dysrhythmias, myocardial infarction, infection, and pericarditis

Holter monitors

Portable ECG used to measure heart activity over 24-hours or longer

Cardiac Imaging

Chest X-ray films used to show shape and size of the heart

Cardiac Computer Tomography scan (CAT)

Many x-rays combined into a 3d model, Iodine based constrast dye highlights blood vessels and creates clearer pictures

Nuclear Imaging

Shows blood flow and used to detect dead or damaged areas of myocardial tissue, with radioactive tracers such as thallium.

Echocardiography

Uses high frequency sound waves (ultrasound), used to record heart valve movements, and image of the heart. Can detect valve abnormalities, congenital defects, changes in heart structure and function.

Cardiac Catheterization

Thin flexible tube (catheter) is inserted into a large artery and is guided to the heart.

Angiography

Done via cardiac catheterization, a contrast dye is injected into the catheter and a series of X-rays show the flow through the coronary arteries. Used to assess valve and heart function, and helps detect clogs in coronary arteries.

Therapeutic interventions for cardiac catheter obstructions

Injection of thrombolytic agent or laser therapy to break down clots

Percutaneous coronary intervention (PCI) formerly known as angioplasty

Uses a balloon to stretch open a narrowed or blocked artery

These procedures are followed by a stent into the coronary artery

Systolic pressure = Systole

Exerted when blood is ejected into the ventricles

CO = HR x SV

Diastolic pressure = Diastole

Relaxation of myocardium required for filling chambers

BP = CO x PR

Regulation of BP - sympathetic nervous system

Increased sympathetic stimulation = vasoconstriction = PR up and BP up

Increased venous return = blood volume up and BP up

Regulation of BP - Hormones

Antidiuretic hormone = BV and BP up

Aldosterone = bv and bp up

Renin and angiotensin = vasoconstriction = pr and BP up also BV up

Etiology of hypertension

Unhealthy diets, excessive salt consumption, no physical activity, tobacco and obesity

Family history of hypertension, age over 65, co-existing diseases, generic ancestry and hormonal factors affecting blood pressure regulation.

Classifications of hypertension

1. primary also called essential _________

2. secondary has identifiable cause from renal or endocrine disorders

3. malignant also called resistant or stage 3 and may result in organ damage

Primary / essential hypertension

1. ≥ 180/110 Hg office BP

2. ≥ 130/80 Hg (diabetes)

3. ≥ 135/85 Hg automated BP

4. ≥ 140/90 Hg OBPM

Signs and symptoms are frequently asymptomatic, initial signs vague and non-specific. Also include fatigue and occasional morning occipital headache

Complications of hypertension

Brain - hemorrhagic stroke, cerebral aneurysms

Eyes - loss of vision (sclerotic changes and rupture of arterioles in retina)

Heart - atherosclerosis, angina, myocardial infarction, congestive heart failure

Kidneys - chronic renal failure

Development of hypertension

Deviation in various physiological processes some of which include functional and structural changes in the autonomic nervous system, renal function notable the renin-angiotensin axis, vascular function, electrolyte balance

Development of hypertension - systemic vasoconstriction

Decreased blood flow to the kidney (RAAS system), meaning BV and PR up

Increased blood pressure can damage the renal blood vessels, increase work for the heart, damage to arteries causing stroke, damage to arterial walls leading to atherosclerosis