Cardiac Health and Testing Procedures Quiz

Nursing Board Review - Cardiovascular System

• The heart is located in the center of the thorax.
• The heart has three layers: epicardium, myocardium, and endocardium.
• The epicardium covers the outer surface of the heart.
• The myocardium is the middle muscular layer of the heart.
• The endocardium lines the chambers and valves of the heart.
• The pericardium is the layer that covers the heart.
• The pericardium has two parts: parietal and visceral pericardium.
• The pericardial space is the space between the two pericardial layers.
• The heart has four chambers: two atria and two ventricles.
• The left atrium and the right atrium receive blood.
• The left ventricle and the right ventricle pump blood.
• The heart chambers are guarded by valves.
• The atrioventricular valves are the tricuspid and bicuspid valves.
• The semilunar valves are the pulmonic and aortic valves.
• The coronary arteries supply blood to the heart.
• The right coronary artery supplies the right atrium and ventricle, as well as the inferior portion of the left ventricle and posterior septal wall.
• The left coronary artery supplies the anterior wall of the left ventricle, the anterior septum, and the apex of the left ventricle.
• The left circumflex branch supplies the left atrium and posterior left ventricle.
• The conduction system of the heart consists of the SA node, AV node, bundle of His, right and left bundle branches, and Purkinje fibers.
• The SA node is the pacemaker.
• The AV node is the slowest conduction.
• The SA node initiates the heartbeat.
• The bundle of His is the pathway for electrical impulses from the AV to to the bundle branches.
• The bundle branches carry the electrical impulses through the ventricles.
• The Purkinje fibers are the fastest conduction.
• The heart sounds (S1 and S2) are due to the closure of heart valves.
  • S1 is the closure of the atrioventricular valves (tricuspid and mitral).
  • S2 is the closure of the semilunar valves (pulmonic and aortic).
• S3 is due to increased ventricular filling.
• S4 is due to forceful atrial contraction.
• Normal heart rate is 60-100 beats per minute.
• Tachycardia is a heart rate greater than 100 bpm.
• Bradycardia is a heart rate less than 60 bpm.
• The sympathetic system increases heart rate.
• The parasympathetic system (vagus) decreases heart rate.
• Blood pressure is controlled by cardiac output and peripheral resistance.
• Baroreceptors in the carotid and aorta detect blood pressure changes.
• Hormones like ADH, aldosterone, and epinephrine increase blood pressure.
• ANF decreases blood pressure.
• The vascular system consists of arteries, veins, and capillaries.
• Arteries carry blood away from the heart.
• Veins carry blood to the heart.
• Capillaries connect arteries and veins, and are lined with squamous cells.
• The lymphatic system is part of the vascular system.
• The lymphatic system collects extravasated fluid from tissues and returns it to the blood.

Cardiac Assessment

• 1. Health History
  • Obtain a description of the present illness and chief complaint (e.g., chest pain, shortness of breath, edema).
  • Assess risk factors (e.g., ethnic background, socioeconomic status).
• Common Symptoms
  • Chest pain/discomfort, pain/discomfort in other upper body areas, shortness of breath, peripheral edema, weight gain, abdominal distention, palpitations, unusual fatigue, dizziness, syncope.

Assessment of the Skin and Extremities (detailed)

• Physical findings
  • Clubbing of the fingers or toes — Thickening of skin under the fingers/toes; may indicate chronic pulmonary diseases, congenital heart disease, etc.
  • Cool/cold skin and diaphoresis — A sign of decreased peripheral blood flow or low cardiac output (like in shock).
  • Cold, pain, pallor of the fingertips or toes — A symptom associated with Raynaud disease (intermittent arteriolar vasoconstriction).
  • Cyanosis (central or peripheral) — Bluish tinge of the skin. Central cyanosis points to issues with oxygenation in the heart; while peripheral cyanosis arises because venous blood stagnates while circulating through the periphery.
  • Ecchymosis or bruising — Purplish-blue discoloration fading to various colors. This could be due to blood leaking outside blood vessels
  • Edema — Swelling due to fluid accumulation; often in the lower extremities.
  • Hematoma — Collection of clotted blood in tissues.
  • Generalized pallor — Decreased skin color; may point to anemia, shock, or low cardiac output..
  • Rubor — Reddish-blue discoloration of extremities. Observed after elevation for a few seconds; usually associated with arterial perfusion issues.

Cardiac Implementation

• 1. Assess cardiopulmonary status (VS, BP, cardiac assessment)
• 2. Enhance cardiac output (establish IV line to administer fluids)
• 3. Promote gas exchange (administer O2, position client in semi-Fowler's, encourage coughing and deep breathing exercises).
• 4. Increase client activity tolerance (balance rest and activity, assist in daily activities).
• 5. Promote client comfort (assess pain, administer medications).
• 6. Promote adequate sleep
• 7. Prevent infection (monitor skin, assess skin site, monitor fever, change patient's position)
• 8. Minimize patient anxiety (encourage verbalization, answer questions, provide information about procedures and medications)

Laboratory Procedures (detailed)

• Cardiac Catheterization

  • Insertion of a catheter into the heart and surrounding vessels.
  • Used to diagnose CAD, assess coronary artery patency, determine extent of atherosclerosis.
  • Pretest requirements: consent, allergy assessment (seafood, iodine), NPO, weight, height, baseline VS, blood tests, peripheral pulse documentation.
  • Intra-test: inform patient of possible fluttering feelings, warmth, and metallic taste if dye is used.
  • Post-test: monitor VS, cardiac rhythm, peripheral pulses, color, warmth and sensation of the extremity distal to the insertion site, maintain sandbag, monitor bleeding/hematoma.
  • Posttest instructions: maintain strict bedrest for 6-12 hours, turn from side to side, but not elevate more than 30 degrees; legs always straight, and encourage fluid intake to flush out dye. Monitor also for dye allergy

• Cardiac Proteins & Enzymes:

  • CK-MB (creatin kinase): Elevates during MI within 4 hours, peaks in 18 hours, and then declines to normal values in 3 days. Normal value – 5-25 IU/L.
  • LDH (Lactate Dehydrogenase): Elevates within 24 hours of MI; peaks in 48-72 hours. Normal LDH1 is less than LDH2 values. (flipped LDH pattern) — Normal value is 70-200 IU/L.
  • Myoglobin: Rises within 1-3 hours of MI, peaks in 4-12 hours, and returns to normal within a day. (Also elevated in muscular/renal disease)
  • Troponin I & T: Used frequently for MI diagnosis; elevates within 3-4 hours of onset, peaks in 4-24 hours, and persists for 7-3 weeks. Normal value for Troponin I is less than 0.04 ng/mL.

• Serum Lipids:

  • Lipid profile - measures cholesterol, triglycerides, and lipoprotein levels. Cholesterol values are 125-200 mg/dL for ages 20 and older; and triglycerides are 40-150 mg/dL; HDL = 30-70 mg/dL; and LDL< 100 mg/dL. NPO is required usually for 12 hours after midnight.

• ECG (Electrocardiogram)

  • Non-invasive procedure to assess electrical activity of the heart; electrodes & wires attached to patient.

• Stress Test

  • Treadmill testing - most common stress test used to determine CAD, chest pain causes, drug effects and dysrhythmias in exercise;
  • Pharmacologic stress test - Uses medication (e.g., Dipyridamole) to evaluate blood flow in the heart, including coronary arteries (which are often maximally dilated.) Side effect often involves skin flushing.
  • Pretest/Post-test instructions for stress tests

• Holter Monitoring

  • Non-invasive ECG monitoring of a patient over 24 hours.
  • Pre-test/Post-test instructions for this test.