Congestive Heart Failure Flashcards
What is Congestive heart failure
Inability of the heart to pump sufficient blood
What causes cardiac remodelling
Ischemia
Excessive workload
Angiotensin 2
Aldosterone
What drugs decreases cardiac remodelling
RAAS inhibitors ACE inhibitors Angiotensin 2 receptor blocker Aldosterone receptor antagonist B blockers
ACE inhibitors mechanism of action
- prils
- Block angiotensin converting enzyme, decrease plasma angiotensin 2
- decrease vasoconstriction, decrease NA+ and H2O retention
- increase bradykinin
ACE inhibitors indications
Chronic HF
Hypertension (primary and secondary causes by DM)
What happens due to Increase in Bradykinin
It causes dry cough and angioedema
-vasodilation and increase in NO
ACE inhibitors adverse effects
Teratogenic, dry cough, angioedema and hyperkalemia
Which ace inhibitors are not metabolised by the liver
Captopril and lisinopril
ACE inhibitors contraindications
Pregnancy Allergy Dry cough Renal insufficiency Bilateral renal artery stenosis
What causes angiotensin escape
Chumash TPA cathepsin
How should ACE inhibitors be dowsed
ACE I should be started at low doses and titrated to target dose
How often is AT blockers administered
Once daily except for valsartan twice daily
Which of the ARBs/ AT blockers is transferred in to active metabolites
Losartan
When and why are ARBs used
When ACE side effects can’t be tolerated because there is no blockade of bradykinin degradation there won’t be dry cough m
Why shouldn’t arbs and ace be used together
Increased risk of hypotension, hyperkalemia and renal dysfunction
List the aldosterone antagonists used for CHF
Spirinolactone and eplerenone
Why are aldosterone antagonists used in CHF
Aldosterone receptors on the heart can lead to cardiac hypertrophy and fibrosis (remodelling)
List B blockers used in CHF
Bisoprolol
Carvedilol
Metoprolol succinate
How is B blocker doses
Start at low dose and titrated up
The starting dose is 10% of target dose
What are the benefits of giving B blockers to people with CHF
Increase survival of myocytes and left ventricular structure and function
Also decrease renin
What should be monitored giving B blockers
BP
HR
EKG
What is recommended for patients with stable symptomatic HFrEF (heart failure with increased ejection fraction)
ACE I and B blocker
Why are diuretics given in CHF
Decrease in plasma volume leads to decrease in preload and after load
Which diuretics are preferred in CHF
Loop diuretics
When to discontinue diuretics in CHF patients
Hypovolemic patient
Ionotropic drugs mechanism of action
Increase Ca2+ in cardiac muscle cells which leads to increase in contractility and increase in cardiac output in
Digoxin mechanism of action
Block Na+/K+ ATPase -> increase of intracellular Na+ ->increase in Ca2+ leading to ionotropic effect
Digoxin half life
36 hours
What should be monitored when digoxin is given
K+
What effects does digoxin have other than on the heart
It overstimulates of sympathetic system causes stimulation of the vagus nerve which increases the renal blood flow that leads to diuresis
Digoxin indications
CHF, atrial flutter and fibrillation
Digoxin adverse effects
Blurred vision m, CNS symptoms, cardiac toxicity (heart block)
Treatment of digoxin toxicity
Lidocaine and propanol
What are PDE I
Mil iron one is a PDE inhibitor it causes increase in CAMP that lead to increase in intracellular Ca2+
Which drugs of CHF can be given in our patient settings
Milieu one and dobutamine
Which cardio vascular drug causes xanthopsia, blurred vision, yellowish vision
Digoxin
Which cardiovascular drug that causes visual disturbances like luminous phenomena
Ivabradine
Which cardiovascular drug causes impairment of blue green colour discrimination
Sildenafil
What should ivabradine be taken with
With meals
Ivabradine mechanism of action
- Selectively binds to funny channels HCN channel (mixed Na+ -K+ current)
- inhibiting pacemaker current in SA node leading to decrease in heart rate
What is ivabradine used for
Used for sinus rhythm
List Vasodilators of CHF
Hydralazine- direct dilatory action on smooth muscle cells
Hydralazine effect
Decrease systolic and diastolic blood pressure
Increase renin activity
List venodilators
Isosorbide dinitrate that is used for angina pectoris
What is H-ISDN
Hydralazine + Isosorbide dinitrate
When is H-ISDN given
It is given to African American patients who continue to have HF symptoms even with optimal doses of ACE-I and B- Blocker
What is the other option other than H-ISDN given to patients who continue to have heart failure symptoms
Replace ACE I with Sacubitril/valsartan
