Exam 2 Flashcards
Beneficial effects of increased preload due to Na/H2O retention
Optimize stroke volume via Frank-Starling mechanism
Detrimental effects of increased preload due to Na/H2O retention
Pulmonary/systemic congestion and edema; increased MVO2
Beneficial effects of vasoconstriction
Maintain BP in face or reduced CO; shunt blood from nonessential tissues to the heart
Detrimental effects of vasoconstriction
Increased MVO2; increased afterload decreases SV and further activates the compensatory responses
Beneficial effects of tachycardia and increased contractility (SNS activation)
Maintain CO
Detrimental effects of tachycardia and increased contractility (SNS activation)
Increased MVO2; shortened diastolic filling time; beta-receptor downregulation and decreased responsiveness; ventricular arrhythmias; increased risk of myocardial cell death
Beneficial effect of ventricular hypertrophy and remodeling
Maintain CO; Reduce myocardial wall stress; decreased MVO2
Detrimental effects of ventricular hypertrophy and remodeling
Diastolic and systolic dysfunction; risk of myocardial cell death and ischemia; risk of arrhythmias; fibrosis
Factors precipitating or worsening HF
AFib, Atrial flutter, inadequate therapy
Which medication classes are negative inotropes?
Antiarrhyhmics, BB, CCB, Itraconazole
What is asymptomatic rEF
No HF symptoms w/ EF<40%
What is HFrEF
HF symptoms with EF<40%
Should a patient withhold fluid if they are fluid overloaded?
Nope
Regular exercise (walking and cycling) should be ______ in all patients with stable HF. The need for cardiac rehab should be ____ in each patient.
Encouraged; assessed
Dynamic exercise (walking, biking, etc.) to increase HR to ____% of maximum for 20-60 minutes ____ times/week.
60-80%
3-5 times/week
How many grams of sodium should a HF patient consume a day?
2-3 grams
Why would a patient have a fluid intake restriction to <2 L/day?
-Hyponatremia (<130 mEq/L)
-If tx with diuretics is difficult in maintaining fluid volume
General measures for pts with HF
-Weight monitoring (and reduction) if necessary
-Non-drug and drug tx; sx of worsening HF
-Smoking cessation
-Immunizations
-Mx and replace electrolytes (esp K and Mg)
-Appropriate thyroid disease management
-Herbal products and nutritional supplements?
Which medication classes decrease intravascular volume?
Diuretics and SGLT2-i
Which medications increase myocardial contractility?
Positive inotropes
Which medications decrease ventricular afterload?
ACE-i, vasodilators, SGLT2-i
Which medications are a neurohormonal blockade?
ARNIs, BB, ACE-i, ARB, MRAs, SGLT2-i
Med class for Stage A HF
ACEi/ARB
Med class for Stage B HF
ACEi/ARB + BB
What stage would a previous MI or asymptomatic rEF be in?
Stage B
What stage is rEF with symptoms?
Stage C
5 therapies used as a basis for stage C HF
ACEi/ARB/ARNI
BB
SGLT2-i
AA
Loop diuretic
If there is a black patient who is persistently symptomatic on the tx for stage C, what should be used?
ISDN/Hydralazine
If a patient is intolerant to ACEi/ARB/ARNI, what should be used?
ISDN/Hydralazine
If a patient is persistently symptomatic on GDMT, what should be used?
Digoxin
Diuretics reduce hospitalizations. Do they have an impact of mortality or natural progression of HF?
Nope
Should patients who do NOT have symptoms of volume overload receive a diuretic? Why or why not?
NO; diuretics may cause electrolyte imbalance. They decrease blood volume which activates SNS and further perpetuates HF
Short-term diuretic benefits
Reduce fluid retention via decreased edema, pulmonary congestion and JVD by reducing preload and cardiac filling pressure
Long term benefits of diuretics
Reduces daily symptoms and improves the ability to exercise
MOA of diuretics
Increase Na+ and H2O excretion by reducing sodium reabsorption at a variety of sites in the nephron—>must get to their site of action to elicit a pharmacological response
Which diuretic classes are the most potent?
Loop and thiazide
Describe sequential nephron blockade
Block loop and DCT with diuretics
With prolonged loop diuretic tx, the cells in the DCT ___ (increase/decrease) their ability to extract sodium and water.
Increase (able to retain these well)
Loop diuretics block the absorption of which electrolytes?
Na and Cl
IV equivalent doses F, B, T, E
F 40 mg = B 1 mg=T 20 mg=E 50 mg
Who would benefit most from thiazide diuretics?
Pts with mild HF and small amount of fluid retention
When would a thiazide be added on to a loop diuretic?
In a patient who becomes resistant to single-drug tx
Adverse effects of loop and thiazide diuretics (fill in the blank with increase or decrease)
____ Mg
____K
____renal function
____Na
____Uric acid
____Ca
decrease
decrease
decrease
decrease
increase
increase or decrease
Numerous studies suggest that ACEi…
-Reduce symptoms
-Improve NYHA
-Improve clinical status
-Decrease hospitalizations
-Improve exercise tolerance
-Improve QOL
ACEi equivalent dosages
20 mg/d enalapril=
150 mg/d captopril=
20 mg/d lisinopril
If an ACEi is used and CrCl<30 ml/min, how much of the target dose should be used?
Half (1/2)
Why does the left ventricle have 2 division branches?
It has a larger muscle mass because it pumps against a higher pressure
How do open spaces in the left atrium become depolarized?
Each cell depolarizes the next cell and it spreads like a wave
(True/False) Arrhythmias will show up in ANY lead
True
(True/False) A 12-lead ECG is needed to detect an MI because it will not show up on all leads.
True
Faster heart rate = ___ (bigger/smaller) QT interval
Smaller
What is Torsades de Pointes?
Ventricular repolarization (QT) interval is too long
At what QT interval do we get worried because it is too long?
> 500 ms = >5 s
Drugs that may cause Torsades de Pointes
Antiarrhythmic agents
Antimicrobials
Antidepressants
Antipsychotics
Anticancer
Opioids
Which patients would we want to keep in the hospital when starting treatment on a QTc prolongating agent?
> 65 y/o
HFrEF or HFpEF
Electrolyte abnormality
Main problem in sinus bradycardia
HR too slow (<60 bpm)
Is there re-entry in sinus bradycardia?
NO
Where is the problem in sinus bradycardia?
Sinus node
Drugs that may cause sinus bradycardia
Digoxin
BB
CCB (non-DHP)
Amiodarone
Dronedarone
Ivabradine
Symptoms of sinus bradycardia
Hypotension
Dizziness
Syncope
Which patients should be treated for sinus bradycardia?
ONLY symptomatic patients
First-line option for symptomatic sinus bradycardia
Atropine 0.5-1 mg IV (repeat q5min; max dose 3 mg)
Options in sinus bradycardia if pt is unresponsive to atropine
Transcutaneous pacing
Dopamine
Epinephrine
Isoproterenol
ADR of atropine
Tachycardia
Urinary retention
Blurred vision
Dry mouth
Mydriasis (dilated pupils)
Medications for patients with symptomatic sinus bradycardia after heart transplant or spinal cord injury
Aminophylline
Theophylline
Most common arrhythmia
AFib
Issue on ECG for AFib
-Atrial activity is chaotic and disorganized
-Ventricular rate: 120-180 bpm
-Rhythm is irregularly irregular
-P waves are absent
AFib
-Is there a P wave in front of QRS?
No
AFib
-Is there a QRS after every P wave?
No; there are no p waves
AFib
-What is the interval between R waves?
Irregularly irregular (No distinct pattern)
BB for ventricular rate control in AFib
Esmolol, Propranolol, Metoprolol tartrate, Metoprolol succinate
Starting dose of carvedilol in HF
3.125 mg BID x 2 weeks
Starting dose of coreg CR
10 mg QD x 2 weeks
Starting dose of metoprolol XL in HF
12.5-25 mg QD
Dose conversion for switching from IR–>ER carvedilol
3.125 BID –10 QD
6.25 BID – 20 QD
12.5 BID – 40 QD
25 BID – 80 QD
Meds used for tx of HFpEF
Entresto
Empagliflozin
Dapagliflozin
Which channels should we avoid blocking in the heart?
hERG because that channel is important for repolarization
Most drugs known to precipitate torsades de pointes should be avoided in patients with diagnosed ____
Congenital LQTS
-Genetic mutations (KCNQ1, KCNH2, SCN5A) cause long QT syndrome
Can a patient with HFrEF be on entresto?
NO! It is contraindicated
BB used in HF
Carvedilol
Metoprolol XL
Bisoprolol (not in US)
What should you ensure before starting a HF patient on a BB?
That they are stable and euvolemic (no marked signs of fluid retention)
BB monitoring
BP
HR
Edema/fluid retention (intensify diuretic if needed)
Fatigue/weakness
Dosing of SGLT2 inhibitors in HF
Empagliflozin and dapagliflozin 10 mg PO QD
eGFR to use dapagliflozin
Greater than or equal to 30
eGFR to use empagliflozin
Greater than or equal to 20
MOA of Digoxin
Inhibits Na+/K+ ATPase altering excitation-contraction-coupling
Goal serum dig concentration
0.5-0.9 ng/mL
Usual dosing range for Dig
0.125-0.25 mg QD
Main ADR with Digoxin
Visual disturbances: halos, photophobia, altered color perception
Name of soluble guanylate cyclase stimulator that decreases CV death and hospitalizations
Vericiguat
Place of omega-3 polyunsaturated fatty acids in HF
As an ADJUNCT
Place of antiplatelets in HF
Long-term tx with ASA is recommended for pts with HF AND IHD/CAD/ASCVD
Should non-DHP CCB be used routinely in HF?
NO!
Should DHP CCB be used routinely in HF?
Only for managing angina/HTN if not effectively managed with HF tx
Lab assessments used to diagnose acute HF
Routine testing of Cr and K; BNP and NTproBNP - BNP>400 is closely associated with acute HF
Hemodynamically unstable criteria
SBP<90 mmHg
HR>150 bpm
Lost consciousness
Ischemic chest pain
It is expected that SC.r can increase as much as __% after initiating/increasing a SGLT2i
20
Should a BB be stopped for a patient experiencing acute HF?
NO! –consider holding IF dobutamine is needed or the patient is hemodynamically unstable
Should Dig be stopped in a patient experiencing acute HF?
NO! continue at the same dose to achieve serum dig concentration 0.5-0.9 ng/mL.
Which 4 drug classes are beneficial in managing decompensation episodes?
Vasopressors
Vasodilators
Diuretics
Inotropes
Hospitalized patients for acute HF should always be given ___ (IV/PO) equal to or exceed chronic daily dose and given as intermittent bolus.
IV
If there is resistance to a diuretic in hospitalized patients, what should be done?
Na+ restriction (1.5 g/d)
H2O restriction (<2L)
Increase dose, rather than frequency, to ceiling
Combo tx (thiazides&loop)
Ceiling effect dosing for IV furosemide
160-200 mg
In which situations would a vasodilator be used in acute HF?
wet; stage 2 and 4
What is the venodilator of choice?
NTG
Arterial vasodilators are useful in patients with ___
Elevated SVR
Pts with symptomatic hypotension ___ (should/should not) receive vasodilators
Should not
Which classes are positive inotropes?
Beta agonists
PDE-3 inhibitors
How long should a positive inotrope be used for?
72-96h or less
When is milrinone preferred over dobutamine?
If SVR is high or BB use
What sodium channel is only expressed in the heart?
Nav1.5
Requirements for re-entry arrhythmia
-Multiple parallel pathways
-Unidirectional block
-Conduction time greater than effective refractory period (ERP)
Does lidocaine help with ventricular arrhythmias, atrial arrhythmias, or both?
Ventricular
Arrhythmias will show up in ___ (any/one) lead
Any
MI will show up in ___ (any/one) lead
One; so need to use a 12-lead ECG
Questions to ask when looking at an ECG
- Is there a P-wave in front of every QRS complex?
- Is there a QRS complex after every P wave?
- Is the interval between R waves all similar?
- What is the rate? (hint: every 5 bigger blocks=1 sec. In class, there are 6s intervals, so you would count the number of R waves and multiply by 10 to get bpm)
At QTc interval length is there increased risk of Torsades de Pointes?
Greater than or equal to 500 ms (5 s)
Sx of sinus bradycardia
Hypotension
Dizziness
Syncope
Tx of sinus bradycardia
Atropine
-If unresponsive to atropine, use transcutaneous pacing, dopamine, epinephrine, or isoproterenol
Tx of sinus bradycardia after heart transplant or spinal cord injury
Aminophylline
Theophylline
Long-term tx of sinus bradycardia
Permanent pacemaker
-If not feasible, use theophylline
(T/F) AFib medications should be given to patients with Stage 4 AFib.
False; this is permanent AFib and patients will NEVER be in sinus rhythm again
What is the main cause of AFib?
Left atrial hypertrophy
Etiologies of reversible AFib
Hyperthyroidism
Thoracic surgery (CABG, lung resection, esophagectomy, valve replacement surgery, sepsis)
Where does blood normally pool in AFib?
Left atrial appendage; gets sucked into left ventricle and out aorta which causes a stroke
Oral anticoagulants are recommended for AFib patients with what CHADsVASc score?
1 in men
2 in women
In AFib, DOACs are preferred over warfarin except for patients with…
-Mechanical heart valve
-AF associated with heart valve disease (mitral valve stenosis)
-Warfarin or apixaban preferred if end-stage CKD (CrCl<15 mL/min) or on hemodialysis.
Dofetilide dose for AFib
CrCl>60 : 500 mcg PO BID
CrCl 40-60: 250 mcg PO BID
CrCl 20-39: 125 mcg PO BID
CrCl<20: C/I
Sx unique to supraventricular tachycardia
“Neck pounding” – blood flowing up to head
Does SVT lead to a stroke?
NO; atria are still contracting so no blood is pooling
Is there increased risk of HF or dementia with SVT?
Not if it is well managed
MOA of premature ventricular complexes
Increased automaticity of ventricular muscle cells/Purkinje fibers
Sx of PVC
Usually asymptomatic
Frequent/repetitive PVCs can result in palpitations, dizziness, light-headedness
Most common etiology for ventricular tachycardia
MI
Which drugs are not used with a history of prior MI
Flecainide
Propafenone
