Chapter 13 - heart disease (questions from the book)

CVD

encompasses group of disorders of teh heart and blood vessels that include:

CAD, cerebrovascular disease, HTN, heart failure, and other conditions

CAD or CHD

pathological process of atherosclerosis → affecting coronary arteries

includes diagnosis of angina pectoris, MI, silent myocardial ischemia, sudden cardiac death

what are pathological conditions that underline CVD?

atherosclerosis, altered myocardial muscle mechanics, valvular dysfunction, arrhythmias, HTN

What is the primary contributer to atherosclerosis?

CVD/CVA and PVD

what results in the impairment of LV function?

alteration in the myocardial muscle mechanics involving the systolic and/or diastolic properties of the myocardium

What does arrythmias cause?

a disturbance in the electrical activity of the heart, resulting in impaired electrical impulse formation or conduction

What is the most prevalent CVD in the US and contributor to cardiovascular morbidity and mortality?

HTN

where is the heart located?

within the left thoracic cavity

Describe the pericardium.

outermost layer; double-walled sac

parietal pericardium

visceral pericardium/epicardium

between the two layers is pericardial fluid serving as lubricant allowing the two surfaces to slide over each other

infection w/ inflammation in this area → pericarditis

Pericarditis

inflammation of the pericardium

what are the two different types of pathologies to differentiate the diagnosis of pericarditis?

pericardial friction rub

cardiac tamponade

Describe the myocardium.

muscular middle layer

facilitates the pumping action of the heart to move blood to the entire body

mechanical cells

conductive cells

what are the classifications of cardiomyopathies?

dilated, hypertrophic, and restrictive

LOOK ON PAGE 417 FOR DESCRIPTION

Describe the endocardium.

form the inner lining of the chambers of the heart and is continuous with the tissue of the valves and endothelium of the blood vessel\

pt’s w/ infections are at risk for developing valvular dysfunction

Where are the coronary arteries located?

originate in the sinus of Valsalva located in the wall of the aorta near the aortic valve

What is the ultimate goal for the heart?

to provide adequate cardiac output to generate aerobic energy to meet the metabolic demands of the body

What is stroke volume?

volume of blood ejected with each myocardial contraction and is influenced by preload, contractility, and afterload

diastole vs systole in the cardiac cycle

diastole: ventricles must be compliant, able to stretch to accommodate blood entering the ventricles (preload)

systole: the ventricles must be able to contract to eject the SV

Describe SV during cardiac cycle.

SV will increase with an increase in preload or contractility and decrease with an increase in afterload

Describe the cardiac cycle.

systole and diastole

first 2/3 of ventricular filling → passive

during the last 1/3 the atria contracts and pushes blood into the ventricles (atrial kick)

pg. 419

Where is the site of gas exchange?

alveolar-capillary membrane (capillaries perfuse the alveoli)

Right-sided heart catheterization

Swan-Ganz catheter or PA catheter that has pressure sensitive recording ability is placed in the internal jugular vein or subclavian vein and progressed antegrade through the right side

lies w/in a relatively low-pressure system provides continuous monitoring of pressures and can be kept in for several days

Left-sided heart catheterizatiion

placing catheter in the femoral or radial artery and advancing retrograde to the flow of blood through the aorta, across the aortic valve, and into the LV where LVEDP can be directly monitored

LV lie w/in high pressure system and can only stay in place for a short period of time due to difficulties with associated with cannulation w/in high pressure system

What does an effective contraction depend on?

an intact electrical conduction system that results in depolarization of the myocardium and timely repolarization

Normal sinus rhythm in chronological order

sinus node and travels through the atria, AV node, bundle of His, Purkinje fibers, septum, and ventricles

P wave

depicts sinus node activation and atrial depolarization

PR segment

demonstrates conduction through the AV node

QRS complex

denotes electrical flow through the ventricles causing ventricular depolarization

ST segment

describes the initiation pf ventricular repolarization

T wave

illustrates the completion of ventricular repolarization

What does the myocardial oxygen supply depend on?

delivery of oxygenated blood through the coronary arteries, the oxygen-carrying capacity of arterial blood, and the ability of the myocardial cells to extract oxygen from the arterial blood

What is the myocardial oxygen demand (MVO2)?

the energy cost to the myocardium

HR x SBP → RPP

any inc in systemic oxygen demand will inc the energy cost if the heart and inc MVO2

what is the primary mechanism for increasing myocardium oxygen supply during times of inc demands?

increased coronary blood flow

what is the heart muscle dependent on?

aerobic metabolism and has very little anaerobic capacity

What is maximal oxygen consumption?

VO2max

reflects the maximum amount of oxygen consumed per min when an individual has reached maximum effort

what is arterial-venous oxygen difference?

the difference b/w oxygen content of arterial and venous blood

reflects the involvement of the peripheral muscle in increasing exercise capacity

Metabolic equivalence (MET)

the amount of oxygen consumed at rest per unit of body weight for 1 min

3.5 mL of O2

represent energy expenditure

white coat hypertension

BP that is consistently elevated at medical practitioner office readings but does not meet diagnostic criteria for HTN based on out-of-office home readings

primary (essential) HTN

there is no known cause for the elevation in BP values and exists in approx. 90-95% of all pts w/ HTN

secondary (nonessential) HTN

caused by identifiable medical problems such as primary renal disease, illicit drug use, renovascular disease, obstructive sleep apnea, Cushing syndrome, endocrine disorders, coarctation of the aorta

acute coronary syndrome

ischemic heart disease or CAD

what is the primary pathophysiology event in ACS?

imbalance of myocardial oxygen supply to meet the MVO2

dec in supply results from narrowing of the lumen (atherosclerosis)

Angina is due to _____.

ischemia (reduced blood flow to the myocardium)

what must balance in order to prevent ischemia?

myocardial oxygen supply and demand (imbalance causes ischemia)

unstable angina

preinfarction angina or crescendo angina

chest pain at rest w/out obvious precipitating factors or w/ minimal exertion

chest pain inc w/ frequency, duration, and severity

stable angina

chest pain during exercise or activity

chest pain is experienced at a certain intensity of exercise when the myocardial oxygen demand exceeds the blood supply to the myocardium and is alleviated by decreasing MVO2

variant or prinzmetal angina

caused by vasospasm of coronary arteries in the absence of occlusive disease

respond to nitroglycerin

injury vs infarction

injury: new acute MI

infarction: old heart attack w/ irreversibly dead tissue

Acute injury to the myocardial tissue then progresses to irreversible, dead infarcted tissue

ischemia vs infarction

ischemia: partial blockage of coronary arteries

infarction: total blockage of blood vessel

patient’s w/ chest pain followed by ECG changes results in…

STEMI or QMI

patients w/ chest pain w/out ECG changes and elevated cardiac enzymes…

NSTEMI or NQMI

patients w/ out chest pain but have positive findings on ECG and elevated cardiac enzymes…

silent MI

most patients with myocardial ischemia will present with classical chest pain referred to as

angina pectoris

pain can be referred to different places due to thoracic and cervical plexus!!

in an ECG, what segment is clinically useful in identifying the presence of impaired coronary perfusion, either injury or ischemia?

ST segment (ST depression will be present)

T wave may also be inverted as well

What segment (specifically) results in acute injury to the myocardium (STEMI)

ST elevation

Percutaneous transluminal coronary angioplasty (PTCA)

uses a balloon and collapsed stent on the tip of a catheter, inserted into radial or femoral artery and advanced retrograde along the aorta to the openings of the coronary arteries

coronary artery bypass graft (CABG)

uses doner vessel to bypass lesion and establish alternative blood supply

uses radial artery of nondominant UE, saphenous vein, or internal mammary artery

less invasive

sternal precautions

to reduce dehiscence of the incision

vary by physician, institution, type of surgery performed

no lifting, pushing, pulling objects greater than 10 pounds

no performing sh flex or abd greater than 90 deg

encourage sh AROM in pain-free range

avoid scapular retraction past neutral

avoid trunk flex and rotation w/ transfers

avoid UE when standing

splinting w/ coughs

limit driving

what is the cause of heart failure?

cardiac muscle dysfunction → altered systolic and/or diastolic activity of the myocardium that usually develops bc of an underlying abnormality

also caused from diseases of the heart (specifics)

left-sided heart failure

hallmark signs: SOB and cough

occurs w/ LV insult

right-sided heart failure

direct insult of RV caused by conditions that increase PA pressure which then increases afterload, thereby placing greater demands on the RV causing it to go into failure; blood is not ejected from RV and back up into RA and venous vasculature

hallmark signs: jugular vein extension and peripheral edema

systolic dysfunction

HFrEF

compromised contractile function of the ventricles causing reduction in CO, SV, and EF

Diastolic dysfunction

HFpEF

ventricles cannot relax and fill appropriately during relaxing phase

this reduces volume of blood ejected w/ each contraction (SV) and the CO; EF is unaltered

Ectopic beats

PVC or PACs

originates in site other than sinus node

PAC

ectopic beat formed in atria and is present as irregular rhythm

is it normal to have a few PVCs even in a NSR?

yes.

can occur due to stress, or with stimulus such as caffeine or nicotine

supraventricular ectopy

rapid firing pf an ectopic focus that originates in any location above the ventricles (atrial or junctional)

paroxysmal atrial tachycardia (multiple PACs), supraventricular tachycardia (multiple PJCs or PACs

What is the treatment respond in a pt present with SVT?

carotid massage

coughing

breath-holding techniques to produce Valsalva maneuver

carotid sinus massage

PVCs → hallmark signs on ECG

absent P wave

wide QRS complex

p.446

ventricular tachycardia

a run of 4 or more PVCs in a row

sustained: HR at least 100bpm and lasts for 30 sec

nonsustained: occurs in groups 3-5 PVCs or a run of 6 or more PVCs; HIGH RISK!

ventricular fibrillation

quivering of the ventricles → inadequate electrical stimulation

sustained runs of different looking PVCs

Automatic Implantable Cardiac Defibrillator

amid to deliver shock if HR is detected higher than programmed limit

implanted in pts who have life-threatening ventricular arrhythmias

PT must limit exercise intensity that may activate device

atrial fibrillation

quivering of the atria

a number of non-sinus-originating p waves exists for each QRS complex

mechanical contractile ability of atria is reduced → results in low atrial kick and compromised CO

pg. 447

what are the most common indications for placement of a permanent pacemaker?

HR is too slow (symptomatic bradycardia)

HR that fails to inc appropriately w/ exercise (chronotropic incompetence)

electrical pathway is blocked, resulting in AV delays or bundle branch blocks

what are the primary functions of the pacemakers?

the ability to sense intrinsic cardiac function

the ability to stimulate cardiac depolarization in response to failed intrinsic activity

the ability to respond in increased metabolic demand by providing rate-responsive pacing

the ability to provide diagnostic information stored w/in the pacemaker

patients who have undergone a heart transplant will present with:

calf cramps owing to the immunosuppressant drug Cyclosporine

dec LE strength

obesity → corticosteroid

inc risk of fracture → osteoporosis associated w/ long-term, high dose corticosteroid

inc probability of atherosclerosis in the coronary arteries

HR is a limited measurement of intensity; must take BP and RPE

what is the goal for cardiac rehabilitation and treatment?

it is geared to control symptoms, improve exercise capacity and tolerance, and improve quality of life

Education for [patients with heart disease should include:

activity guidelines, self-monitoring, symptom recognition and response, nutrition, medications, lifestyle issues, sexual activity