Heart Failure Flashcards
Describe Frank Starling’s Law.
Pressure is proportional to SV.
increase EDV = increase PRELOAD = increase SV = increase CONTRACTILITY
Presentations of Left Heart Failure
[PERIPHERAL CONGESTION]
- Peripheral edema (increase in abd. girth)
- LOC, fatigue (ischemia)
- Impaired liver fx (liver congestion)
- End organ failure/anorexia, weight loss, GI distress (GI congestion)
Presentations of Right heart failure
- Decreased CO
- Activity intolerance + Hypoxemia (low perfusion) - Impaired gas exchange
- Cyanosis/Hypoxia (impaired gas exchange) - Pulmonary edema
- Orthopnea
- Paroxysmal nocturnal dyspnea
- Wet cough
What is orthopnea?
Breathlessness when laying down.
- Sx: LS heart failure
Paroxysmal nocturnal dyspnea
SOB that awakens a person
- Sx: LS heart failure
Inotropy
Medications that alter heart’s contractility
What is the focus of tx for HF?
- Decrease cardiac workload + increase O2 supply
2. Increase contractility
Cardiac Glycosides
- MOA? (2)
- Tx for _____?
- Common medications
- Contraindications?
MOA: Affects overall electrolyte transport across cell membrane
- Blocks NA/ATPase = high NA-Ca exchange in cell = increased contractility
- Slow electrical conduction @ AV node = lowers HR + increases CO
Tx:
- Chronic HF
- Arrhythmias
Common drugs:
- Digoxin (Lanoxin), Digitoxin
Contraindications:
- Apical pulse for 1 min <60bpm = HOLD
- Antidote for toxicity: DIGIBIND (1st sign is N+V)
Digitalization
The loading dose of cardiac glycosides
P-Inhibitors
- MOA?
- Tx for ____?
Block phosphodiesterase (PDE) = increases cAMP
- Increases contractility of myocardial cells
- Vasodilation/relaxation of smooth muscle cells
Tx: Acute HF
What drug class does Viagra belong to?
P-Inhibitor
- Increase BF to genitals = erection
Milrinone, Amrinone
Drug class?
What is it used to treat?
P-Inhibitors
Tx: Acute HF
Adrenergic Agonists
- What is the MOA?
- Tx for _____?
MOA (mimic catecholamines)
- Increases contractility
- Increases CO
- Vasodilation
Tx: Acute HF
What drug class does "Dobutamine" belong to? - Tx for \_\_\_\_\_\_?
Adrenergic Agonists: direct sympathomimetic (beta-1 specific)
Tx: Acute HF
What drug class does "Dopamine HCL" belong to? - Tx for \_\_\_\_\_\_?
Adrenergic Agonists: non-selective beta (precursor to Norepi)
Tx: Acute HF
What meds are used to tx Acute Heart Failure?
- Loop diuretics = decrease preload
- Direct Acting Vasodilators or NO = dilate
- B1 Agonists = increase contractility
- P-inhibitors = increase contractility in heart cell + vasodilation in smooth muscle cell
What meds are used to tx Chronic Heart Failure?
- Cardiac glycosides > B1 agonists
2. ACE, ARBs > NO
Arrhythmia
- Different stimuli (3)
- Tx
Problem with rate/rhythm of heartbeat.
Stimuli:
- Re-entry circuits to SA node (Afib, SVT)
- AV node dfx
- PNS stimulation (vagal nerve)
Tx:
- Decrease SA-AV node conduction
- Digoxin
- ITN: Ablation (long term; low efficacy) - Depress ectopy @ ventricular level
- alters cell fx - Enhance normal AV conduction
- Meds are block ion transport (Na, K)
Supraventricular tachycardia (SVT) - Describe txs
A group of abnormally rapid heartbeats that starts in the atrias.
Tx
1. CARDIOAVERSION: interrupts ventricle depolarization through low voltage
- ADENOSINE: inhibits cerebral synapse @ adenosine receptors
* *Sedative, but shares same receptor as caffeine! - ANTIARRHYTHMICS (Digoxin, Lidocaine, Amiodarone)
Lidocaine
Anti-arrhythmic - Enhances normal AV conduction by blocking Na-channel
Amiodarone
Anti-arrhythmic - Enhances normal AV conduction by blocking K-channel
Atrial fibrillation
Irregular heartbeats and rapid arrhythmia that can lead to blood clots.
- Caused by CAD, etc.
Sinus rhythm
The rhythm of your heart beat, determined by the sinus node of your heart.
What classes of medications are used to treat HF?
- Anti-hypertensives (Diurectics, ACE/ARBs, AA, NO, CCB)
- Cardiac glycosides
- P-inhibitors
- Adrenergic Agonists
