unit 8 patho

A client with a history of acute coronary syndrome asks why she needs to take aspirin 81 mg every day. The most appropriate response by the nurse would be:

"Aspirin will help prevent blood clotting."

A nurse is observing a client's cardiac status by telemetry monitoring. On the monitor, the P wave changes shape and an impulse frequently occurs before the next expected sinoatrial (SA) node impulse. The nurse interprets this rhythm by stating:

"The client is experiencing premature atrial contractions (PACs)." Explanation: PACs are contractions that originate in the atrial conduction pathways or atrial muscle cells and occur before the next expected SA node impulse. This impulse to contract usually is transmitted to the ventricle and back to the SA node.

A client with an ST elevation myocardial infarction (STEMI) receives a coronary stent in the obstructed vessel. Which instruction will the client receive for the immediate post-procedure period?

"Watch for bleeding at the catheter insertion site."

Classification of HTN - systolic

- normal (less or equal to 119), - prehypertension/elevated (120-129), - stage 1 HTN (130-139), - stage 2 HTN (140+)

Pericarditis S/S

-Radiating chest pain (neck, back, abdomen, side) relieved by sitting up and/or bending forward; worsened by lying down or -deep breaths/swallowing causes pain -sharp chest pain that starts abruptly -pericardial FRICTION RUB -ekg changes

who would benefit from a pacemaker?

-atrioventricular heart block -symptomatic bradycardia -other cardiac arrhythmias

Autonomic nervous system control of blood pressure is mediated through which physiologic process:

-baroreceptors in blood vessels -carotid artery chemoreceptors -pain and strong emotion -aortic chemoreceptors

What are chordae tendinae?

-cordlike structure -support AV valves to prevent eversion into atria during systole

pericardial effusion

-exudate in pericardial cavity -can be acute or chronic acute: chest pain, ECG changes, and pericardial friction rub.

Sinus Dysrhythmia (Arrhythmia)

-gradual lengthening and shortening of the distance between the QRS complexes -caused by thoracic pressure changes occurring during respiration, which cause changes in the autonomic control of the SA node. -distance between the complexes shortens during inspiration because the heart rate increases -lengthens during exhalation as the heart rate decreases.

risk factors for developing HTN

-intravascular fluid retention -elevated renin levels -systemic vasoconstriction -increased blood volume

arterial chemoreceptors

-regulation of ventilation -trigger increase in BP for sleep apnea -induce systemic HTN for pt w/COPD

If the Purkinje fibers became the pacemaker of the heart, what is the expected heart rate?

15-40bpm

A client has a myocardial infarction (MI) that has damaged the right atrium, which results in interference with the SA node. The compensatory mechanism, the AV node, becomes the pacemaker of the heart and beats how many times per minute?

45 to 50 beats/minute

ST-elevated myocardial infarction (STEMI) is accompanied by severe, crushing pain. Morphine is the drug of choice used to treat the pain of STEMI when the pain cannot be relieved with oxygen and nitrates. Why is morphine considered the drug of choice in STEMI?

Action decreases metabolic demands of the heart. Explanation: Although a number of analgesic agents have been used to treat the pain of STEMI, morphine is usually the drug of choice. It usually is indicated if chest pain is unrelieved with oxygen and nitrates. The reduction in anxiety that accompanies the administration of morphine contributes to a decrease in restlessness and autonomic nervous system activity, with a subsequent decrease in the metabolic demands of the heart

A client who has just recently completed their second series of radiation therapy for lung cancer was admitted yesterday to an acute care facility with ascites. The client begins to have jugular vein distention, pedal edema, and dyspnea upon exertion as well as fatigue. What should the nurse suspect?

Client has developed constrictive pericarditis.

Which of the following describes surgical correction of tetralogy of Fallot?

Closure of the ventricular-septal defect and relief of the right ventricular outflow obstruction

Which health conditions can contribute to diastolic dysfunction heart failure?

Conditions that reduce the heart's ability to adequately fill during diastole -myocardial hypertrophy -tachycardia

(6) Causes of dysfunction of heart valves

Congenital defects Rheumatic heart disease Trauma Ischemic heart disease Inflammation Degenerative changes

The heart controls the direction of blood flow. What is the role of the aortic valve?

Controls the direction of blood flow from the left side of the heart to the systemic circulation

What causes the loss of contractile function of the heart within seconds of the onset of an MI?

Conversion from aerobic to anaerobic metabolism Explanation: The principal biochemical consequence of MI is the conversion from aerobic to anaerobic metabolism with inadequate production of energy to sustain normal myocardial function. As a result, a striking loss of contractile function occurs within 60 seconds of onset.

A client has been diagnosed with runs of intermittent ventricular tachycardia where the client loses consciousness and needs to be stimulated to recovery. Knowing this history, the nurse will educate the client about which treatment intervention/procedure that will depolarize the heart to allow the sinoatrial node to regain control of the heart?

Education involving automatic implantable cardioverter-defibrillators implantation

A. flutter vs A. fib

Flutter: ventricular response is variable; atrial rate 200-500 Fib: ventricular response is irregular; atrial rate 400-600

how to calculate cardiac output

HR x stroke volume

The ECG reveals a first-degree atrioventricular (AV) block, which is characterized by:

PR interval >0.20 seconds -prolong PR interval indicates delayed AV conduction

What is the most important factor in myocardial oxygen demand?

Heart rate Explanation: The heart rate is the most important factor in myocardial oxygen demand since, as heart rate increases, myocardial oxygen demands increase.

A young college football player was bought to the emergency room after collapsing on the football field during practice. When arriving he was unconscious and his ECG was abnormal. Subsequently he died after arresting in the emergency room. What does the physician suspect is the likely cause of this?

Hypertrophic cardiomyopathy Explanation: Hypertrophic cardiomyopathy is characterized by unexplained left ventricular hypertrophy with disproportionate thickening of the interventricular septum, abnormal diastolic filling, and cardiac dysrhythmias. Hypertrophic cardiomyopathy is the most common cause of sudden cardiac death in young athletes.

Which statement regarding heart failure is true?

In compensated heart failure, an increase of end-diastolic volume causes increased force of left ventricular contraction. Explanation: In compensated failure, the increase in diastolic filling and stretch on the left ventricle exert an increase in the force of contraction (Frank-Starling Law) until the stretch becomes too great and ventricular efficiency declines.

An 86-year-old client is disappointed to learn that he or she has class II heart failure despite a lifelong commitment to exercise and healthy eating. Which age-related change predisposes older adults to the development of heart failure?

Increased vascular stiffness Explanation: Increased vascular stiffness in older adults causes a progressive increase in systolic blood pressure with advancing age, which in turn contributes to the development of left ventricular hypertrophy and altered diastolic filling

A 22-year-old man is experiencing hypovolemic shock following a fight in which his carotid artery was cut with a broken bottle. Which immediate treatments are likely to most benefit the man?

Infusion of normal saline or Ringer's lactate to maintain the vascular space. Explanation: Maintenance of vascular volume is the primary goal in the treatment of hypovolemic shock and can be achieved in the short term through intravenous administration of saline solution or Ringer's lactate.

Smoking effect on heart

Injures the endothelial cells lining the blood vessels, thereby promoting thrombus development -increases serum lipid levels -decreases HDL -promotes vasoconstriction

ischemia

Lack of blood supply

The nurse has just completed teaching a client about acyanotic congenital heart disease. The nurse determines that teaching was effective when the client states the blood is shunted to which part of the body?

Left side of the heart to the right side of the heart Explanation: Defects that result in a left-to-right shunt are categorized as acyanotic disorders since they do not compromise oxygenation of blood in the pulmonary circulation.

Increased secretion of renin in heart failure is caused by which event?

Low cardiac output Explanation: Low cardiac output reduces renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS). This system produces the vasoconstrictor angiotensin-ll and aldosterone, which increases sodium and water retention

Which diagnostic/assessment findings would be seen in a client with worsening mitral valve stenosis?

Low-pitched diastolic murmur that is increasing in duration Sharp elevation in left atrial pressure Decreased cardiac output

Sick sinus syndrome is suspected in the case of a child who is postoperative following cardiac surgery. Which nursing action is most appropriate?

Monitor the child's ECG for bradycardia. Explanation: The simple ECG would be enough to give a preliminary diagnosis of sick sinus syndrome, which typically reveals persistent sinus bradycardia

The nurse is evaluating the client's cardiac rhythms and notes a very irregular rhythm with P waves before most if not all the QRS complexes with a rate of 140. With closer inspection of the cardiac rhythm, the nurse notes the P waves all look different. Which term most accurately describes this rhythm?

Multifocal atrial tachycardia

What is sinus arrest?

SA node fails to discharge; irregular pulse; can predispose patients to other serious arrhythmias -can result in prolonged periods of asystole -may need pacemaker

heart conduction system

SA node, AV node, bundle of His, bundle branches, and Purkinje fibers

Which one of the following organs are the two primary sites of lipoprotein synthesis

Small intestine and liver

most common cause of infective endocarditis

Staph aureus (infection) other causes: streptococci and enterococci

Which blood vessel layer is made primarily of muscle?

Tunica media Explanation: The middle layer (tunica media) of a vessel is largely a smooth muscle layer that constricts to regulate and control the diameter of the vessel.

What conditions are associated with systolic heart failure/impaired contractile performance?

Valvular insufficiency, anemia, and ischemic heart disease

A client with new onset atrial fibrillation (AF) is being admitted to the hospital for possible cardioversion. The initial vital signs include a heart rate of 160 and blood pressure of 90/60. The admission nurse anticipates the presence of a pulse deficit. To verify this finding which action would the nurse take?

With another nurse, assess the apical and radial pulses simultaneously for one minute. -The most accurate means of assessing a pulse deficit is for two nurses to assess at the same time, one the apical rate and the other the radial. Then the radial rate is subtracted from the apical rate to determine the number of ventricular contractions that are not producing a palpable pulse.

laminar blood flow

allows blood layers to slide smoothly by reducing friction

ACE inhibitors block conversion of ___________ and ___________.

angiotensin I angiotensin II -commonly prescribed for CHF

infarction

area of dead tissue - necrosis

P-wave

atrial depolarization (SA node)

antiarrhythmic med used for blunting the effect of sympathetic NS stimulation on the heart

beta-blockers; inhibits calcium channel f/opening(decreases HR/cardiac contractility) -metoprolol -propranolol -atenolol -timolol -sotalol

tetralogy of fallot

congenital malformation involving four distinct heart defects -skin tinged blue r/t poor oxygen perfusion in blood -SOB/rapid breathing (esp during eating/exercise) -poor wt gain -fatigue/tired easy -irritable -heart murmur -fainting -clubbed fingers/toes

QRS complexes greater than 0.12 second could indicate:

delayed conduction in the bundle branches

baroreceptors

detect changes in blood pressure

Left-side HF S/S

dyspnea cough fatigue r/t reduced cardiac output/inadequate tissue perfusion orthopnea pulm congestion

what should the nurse teach a client with peripheral vascular disease and intermittent claudication about exercise?

exercise can increase blood vessels growth and help decrease symptoms -induces angiogenesis w/increased growth of vessels to support blood flow to the exercising muscle. -can decrease pain in pt with peripheral vasc. disease

CHF primary treatment goal

improving quality of life by relieving symptoms. Explanation: A primary treatment goal for a client with CHF is to improve the quality of life through symptom management. CHF will not be cured

Bundle Branch Block (BBB)

interruption in the electrical impulse's ability to travel through the bundle of His at the normal rate, which would result in QRS complexes of 0.08 to 0.12 second.

lipoprotein that is the main carrier of cholesterol

low-density lipoprotein (LDL)

coarctation of the aorta

narrowing of the aorta

tunica externa (adventitia)

outermost layer of blood vessel -made of loosely woven collagen fibers

sinoatrial node

pacemaker of heart

A client experiencing increasing fatigue in recent months has an echocardiogram that reveals the client's end-diastolic volume is insufficient. Which other parameter of cardiac performance will directly decrease as a result?

preload -Preload is the volume of blood stretching the heart muscle at the end of diastole and is normally determined by the venous return to the heart.

When the AV valves are closed, what is their function?

prevent backflow of blood from ventricles during systole

What are the semilunar valves?

pulmonary and aortic -prevent backflow from aorta and pulm arteries into ventricles during diastole

Renin function

regulates blood pressure -enzyme secreted by kidneys

Treatment for varicose veins

sclerotherapy or surgery

The nurse should anticipate administering intravenous antibiotic therapy as a priority to a client experiencing which type of shock?

septic shock

troponin

serum biomarker highly specific to myocardial tissue -primary blood test done for diagnosis of MI

tunica intima

the innermost layer of a blood vessel, composed of a single layer of flattened endothelial cells

external pulse generator

transcutaneous pulse generator -type of pacing involves the placement of large patch electrodes on the anterior and posterior chest wall that can be connected by a cable to an external pulse generator

Valvular regurgitation (insufficiency)

valve leaflets, or cusps, that are floppy and fail to shut completely, permitting blood flow even when the valve should be completely closed.

What is systole?

ventricular Contraction of the heart

What is diastole?

ventricular Relaxation -heart fills w/blood

QRS wave complex

ventricular depolarization

t-wave

ventricular repolarization

when is blood rapidly moved from central circulation to LEs?

when a pt is helped out of bed and stands up -during body position changes from lying to sitting/standing, blood is rapidly relocated to the LEs and can result in a temporary drop in BP (postural hypotension)

where is the pericardial space located?

between parietal(outer) and visceral(inner) layers

pulmonic valve

between right ventricle and pulmonary artery -controls flow of blood into pulmonary circulation

Aortic valve

between left ventricle and aorta -controls flow of blood inti systemic circulation

how are valvular defects (like aortic stenosis) detected?

cardiac auscultation -loud systolic murmur or a single-split second heart sound heard (aortic stenosis)

how to calculate mean arterial BP

cardiac output x systemic vascular resistance

fibrous atheromatous plaque (atherosclerosis)

causes lesions in coronary arteries that reduce the size of the vessel lumen -pt may experience SOB and chest pain

tunica media

smooth muscle -produce vasoconstriction/vasodilation of blood vessels

congenital heart defects

structural abnormalities caused by the failure of the heart to develop normally before birth -occur between 3rd and 8th weeks of development