Cardiac Test 2

• Action: Increased heart rate (beta-adrenergic) and blood pressure from
• vasoconstriction (alpha-adrenergic). There is also increased venous return to the heart, which stretches the myocardial fibers. This increased stretch is a preload that makes a more forceful contraction, increasing stroke volume and CO.
• Long-term effects: Increased oxygen demand; increased afterload, which is the resistance against which the heart must pump; too much myocardial stretch (preload).

• Action: The walls of the heart become thick, increasing muscle mass and
• increasing the force of contraction.
• Long-term effect: The heart cannot meet the increased oxygen demand that hypertrophied condition requires.

• Action: Activates the renin-angiotensin system, which raises the blood pressure by increasing fluid retention and vasoconstriction.
• Long-term effect: This eventually increases the stretch (preload) and the
• resistance (afterload). Ventricular remodeling may develop.

• Systolic dysfunction (systolic
• ventricular dysfunction)

• Cardiac output decreases. Symptoms
• of inadequate tissue perfusion,
• pulmonary and systemic congestion
• occur.

• Diastolic dysfunction (diastolic
• ventricular dysfunction)

• Diminished tissue perfusion
• and decreased cardiac output.
• Symptoms similar to those of systolic
• dysfunction.

Arteriosclerosis is a thickening or hardening of the arterial wall resulting in a loss of elasticity.

Atherosclerosis is a form of arteriosclerosis that involves the formation of plaque within the arterial wall, which leads to eventual interference with blood flow through the artery.

• Intimal layer of artery is injured
• Fatty streak is deposited on intimal layer
• Fibrous plaque develops
• Calcification, thrombosis, ulceration of fibrous lesions occur

Plaque is white and fibrous, and partially or completely blocks the flow of blood in an artery

• Mechanical Injury: hypertension
• Chemical Injuries: toxins from renal failure, carbon monoxide from smoking
• Natural Causes: aging
• Diseases: diabetes, hyperlipidemia
• Others: stress (type A personality is uptight, type D personality is depressed), obesity, and sedentary lifestyle

• Rate of progression depends on factors that cause the injury and the number of risk factors that a patient has.
• For example, if a patient is older, eats a high fat diet, and has diabetes, the rate of progression is high.

A fatty streak is a fatty deposit on the inner lining of the arteries but not enough to affect the integrity of the arterial wall

• Women with waists greater than 35in
• Men with waists greater than 40in

• The abrupt rupture allows procoagulant lipids to flood into the vessel lumen and rapidly form a coronary thrombosis.
• As the enlarging clot blocks blood flow through the coronary artery, a "heart attack" will occur unless there is adequate collateral circulation from other coronary vessels
• Symptoms associated with this cap rupture include chest pain not relieved by rest or Nitro.
• This is considered an Acute Coronary Syndrom- unstable angina

• Vulnerable plaque
• As deep fissures in the cap expose the procoagulant factors to the blood plasma, an unstoppable cycle is put into motion.
• As the liquid inner core travels through the cardiovascular system, it collects RBCs and other debris along the way forming a clot that can occlude the coronary artery(microembolism occulsion)
• Vulnerable plaques are usually not obstructive like calcified plaques are

• Calcified Plaque
• Although stable it can occlude
• The part of the artery that is calcified can no longer constrict or dilate
• Calcified plaque is related to the aging process where vulnerable plaque is related to lifestyle

• No but, it can decrease the plaque size by decreasing the amount of liquid cholesterol within the plaque core.
• Lower cholesterol levels also reduce vascular inflammation and make vulnerable plaque less likely to rupture

Acute Coronary Syndrome (ACS)

• Stable manifestation of CAD is referred to as stable angina
• Acute manifestations of CAD are described as an acute coronary syndrome and refers to unstable angina and acute MI

Angina

It is a symptom not a separate disease

• Chest discomfort, pressure or pain
• Angina may occur anywhere in the chest, neck, arms, or back.
• Most commonly described location is pain or pressure behind the sternum that radiates to the left arm but can also radiate down both arms and to the back, shoulder, jaw, or neck
• Teach that angina does not always present in the dramatic scenarios seen on TV

• Unexpected shortness of breath
• Breaking out in a cold sweat
• Sudden fatigue, nausea, or lightheadedness
• More women die every year of cardiovascular disease than men

Parasympathetic Nervous System Decreases all functions

Sympathetic Nervous System Increases all functions

Stable Angina

• Fixed lesions (blockages) of more than75% of the coronary artery lumen
• Ischemia and chest pain occur when myocardial demand from exertion exceeds the blood oxygen supply
• Pain control should be achieved within 5 minutes by rest and by taking sublingual nitro

• Unstable Angina
• More intense than stable angina, may awaken the person from sleep, or may necessitate more than nitrates for pain relief
• A change in the level or frequency of symptoms requires immediate evaluation
• Severe angina that persists for more than 5 minutes, is worsening in intensity, and is not relieved by one nitro tablet is a medical emergency

• Atherosclerotic plaque instability
• It can signal atherosclerotic plaque rupture and thrombus formation that can lead to MI

Preinfarction symptoms (Unstable Angina)

• Chronic inflammation of arterial wall
• 
• Plaque formation
• 
• Atherosclerotic plaque ruptures
• And/Or