Heart Failure & Cor Pulmonale & A-fib/flutter

Question 1

_____ x ______ = cardiac output

Answer 1

stroke volume x heart rate = CO (amount of blood your heart can beat in 1 min (mL/min)

Question 2

What is stroke volume determined by

Answer 2

preload, afterload, and ventricular contractility (SV = EDV-ESV)

Question 3

Describe the Frank-Starling law

Answer 3

• greater EDV increases contractile strength of the ventricles which increases SV
• myocardium will be more stretched d/t greater volume which leads to stronger contraction

Question 4

How does the sympathetic nervous system maintain cardiac output

Answer 4

improves ventricular contractility and HR, systemic arteriolar vasoconstriction

Question 5

how does the RAAS system maintain cardiac output

Answer 5

• increased angiotensin II, vasoconstrictor that attempts to maintain an adequate BP
• increased aldosterone, hormone that increases plasma volume to maintain adequate ventricular filling (preload)

Question 6

how does ADH secretion maintain cardiac output

Answer 6

increases ventricular filling (preload) by decreasing water excretion in the urine & increasing thirst

Question 7

What is the downside of the SNS, RAAS, and ADH secretion maintaining cardiac output in the context of heart failure long term?

Answer 7

structural changes to the heart that are damaging

Question 8

When is natriuretic peptide released and what can it tell us in the workup for HF (BNP & NT-proBNP labs)

Answer 8

• released d/t stretching of ventricular walls or increased pressure upon the walls
• in HF this increases water and sodium excretion in the urine
• serial BNP levels to guide management of acute HF not established & should not be used in isolation to exclude or confirm HF (high negative predictive value)

Question 9

Describe the etiology of heart failure

Answer 9

heart unable to pump enough blood to meet body’s need for O2

Question 10

What is the most common cause of left sided heart failure

Answer 10

CAD (then dilated CMO, restrictive CMO, & hypertrophic CMO)

Question 11

What is the most common cause of R sided HF

Answer 11

L sided HF

Question 12

Describe the major types of HF

Answer 12

• HFrEF: EF <40%
• HFpEF: EF >50%
• HFimpEF: EF previously <40% but now greater
• HFmrEF: EF 41-49%
• high output HF

Question 13

What are the major RFs for HF

Answer 13

CAD, HTN, DM, valvular disease, smoking, obesity

Question 14

Describe the major signs/symptoms of HF

Answer 14

Fatigue, weakness, dyspnea on exertion, cough, orthopnea, paroxysmal nocturnal dyspnea, GI sxs, weight gain, LE edema

Labored breathing, need to sit upright, sinus tach (increased adrenergic activity), peripheral vasoconstriction (cool extremities, cyanosis of lips & nail beds)

Question 15

Describe the diagnostic testing for HF

Answer 15

EKG: may see acute ischemia as cause of new-onset HF, may provide info about etiology of HF (arrhythmia, LVH), low specificity

Labs: CBC, CMP (renal fx, electrolytes - Na & K, liver enzymes), cardiac enzymes, brain or B-type natriuretic peptide (BNP) and N-terminal BNP (NT-proBNP)

CXR: helpful in identifying cardiac v pulmonary etiology, signs of acute decompensated HF include cardiomegaly, pleural effusion, interstitial edema (Kerley B lines), cephalization of vessels (upper lobe vessels larger than lower lobe vessels)

Echo: assess size & function of chambers, valves, pericardial effusion, shunting & regional wall motion, segmental wall abnormalities, determines LV EF

Question 16

Describe the etiology/causes of cor pulmonale

Answer 16

Pulmonary HTN induced altered structure (hypertrophy or dilation) and/or impaired fx of R ventricle associated with chronic lung disease/hypoxemia

Pulmonary HTN related to lung disease increases RV afterload & can lead to R heart failure

Causes: COPD, PE, CF, interstitial lung dz, pneumoconiosis

R heart failure d/t pulm dz

Question 17

Describe the clinical presentation of cor pulmonale

Answer 17

Dyspnea, orthopnea & PND rarely sxs of isolated RF, tussive or effort related syncope d/t inability of RV to deliver blood to L side, sxs of right HF

Ascites, peripheral edema

Question 18

Describe the treatment for cor pulmonale

Answer 18

Treat underlying pulm dz

Oxygenation >90-92%

Diuretics effective in treating volume overload d/t right HF

Pulmonary vasodilators

Question 19

Describe the 4 major types of A-fib

Answer 19

Paroxysmal: starts spontaneously & stops within 7 days

Persistent: duration 7+ days

Long-standing persistent: 1+ year

Permanent: persistent AF who have made decision with provider to stop attempts to control rhythm

Question 20

Describe the sxs of a-fib

Answer 20

asymptomatic, fatigue, palpitations, lightheadedness, SOB, chest pain, anxiety, reduced exercise capacity, stroke

Question 21

Describe the etiology of a-fib

Answer 21

Rapid firing ectopic foci mainly from pulmonary veins that overrides the SA nodes, AV node receives 500+ and allows only some to pass (120-180 bpm)

Impaired atrial contraction - decreased preload & CO - remodeling of atrium (less likely to spontaneously return to NSR)

Question 22

Describe the two major categories of a-fib treatment (technically 3)

Answer 22

Rhythm control:
- cardioversion (required in persistent AF, preferred in symptomatic paroxysmal, urgent if unstable)
- antiarrhythmic drugs: propafenone, flecainide, amiodarone (Many AEs)
- catheter ablation (1st or after AAD)

Rate control:
- B-blocker: metoprolol
- Non-DHP Ca Channel blocker: diltiazem, verapamil
- can add digoxin if not effective

Anticoag:
- Vit K antagonist (Warfarin)
- Direct acting: Factor Xa (Xarelto, Eliquis), antithrombin inhibitor (Pradaxa)

Question 23

Describe the EKG of a-fib

Answer 23

irregularly irregular appearance of QRS complex, absence of discrete P waves

Question 24

Describe the EKG of a-flutter

Answer 24

atrial rate 250-350 bpm, often conducts to ventricles with 2:1 AV block creating a regularly tachy at 150 bpm, atrial “sawtooth”

Question 25

Describe the CHADS(2) VASc score

Answer 25

Thromboembolic risk