Heart Failure Treatments PDF

What treatments are given to patients with heart failure Vasodilators ACE inhibitors Diuretics Positive inotropes What is the treatment in chronic heart failure If congestive symptoms, like fluid retention occurs, give a loop diuretic If there is a risk of thrombosis, then an anticoagulant should...

What treatments are given to patients with heart failure Vasodilators ACE inhibitors Diuretics Positive inotropes What is the treatment in chronic heart failure If congestive symptoms, like fluid retention occurs, give a loop diuretic If there is a risk of thrombosis, then an anticoagulant should be considered, avoid verapamil as it blocks cardiac calcium channels  They are furosemide, bumetanide and torsemide They are used in patients that have pulmonary oedema = due to acute What are loop left ventricular failure diuretics? Used in patients with chronic heart failure Used in adjunction to antihypertensive treatment in resistant hypertension Increase vasodilator effect It is given by intravenous administration and relief breathlessness and reduction in pre-load sooner than onset diuresis What is the mechanism of action of loop diuretics and their pharmacokinetics? They reduce electrolyte reabsorption in thick ascending limb of the loop of Henle, promote urinary excretion of Na+, Cl-, K+ and H2O. It works on the Na+/K+/2Cl- transporters. They are high potent diuretics and produce a high ceiling effect It is orally administered with GI absorption, around 50% bioavailability (orally), peak effect is 30 mins and half-life is 2 hrs and action lasts 4-6 hrs. If given by IV, its effect lasts 10 mins It undergoes liver cytochrome P450 metabolism They are powerful as they cause excretion of 20- 25% of filtered Na+ What are the side-effects, cautions and contraindications of loop diuretics? Side-effects of loop diuretics are dizziness, electrolyte imbalance, fatigue, headache, metabolic alkalosis, muscle spasms & nausea Cautions of loop diuretics are:  Risk if urinary retention if enlarged prostate  Risk of hypovolaemia, hypotension & hypokalaemia (hypokalaemia risk is reduced by a K+ sparring diuretic)  Use lower dose in elderly Contraindications of loop diuretics are Anuria, drug-induced renal failure, severe hypokalaemia and severe hyponatraemia What does it say about treatment of heart failure with reduced ejection fraction in NICE? Heart Failure reduced cardiac function (reduces ejection fraction by 40%): First line treatment is ACE inhibitor plus a beta blocker If symptoms continue give a mineralocorticoid receptor antagonists = Spironolactone Specialist treatments are: Ivabradine, Digoxin, SGLT2 inhibitors – Dapagliflozin, Sacubitril Valsartan & hydralazine with nitrate Beta Blockers: Bisoprolol, Carvedilol & Nebivolol It inhibits adrenergic beta-1 receptors, blocking the effects of adrenaline and noradrenaline & inhibits release of renin (same action in hypertension) It slows rate of firing of SAN/AV node in the heart (affects cardiac nodal tissue), It has a negative ionotropic effect and reduces cardiac contraction Side-effects is dizziness, tiredness and blurred vision Most people either have mild side-effects that become less troublesome with time Start treatment should be low dosage and slowly up the dosage  if already taking a beta blocker for angina or hypertension (switch to recognised beta blocker in heart failure) Check hypertension treatments for ACEi’s and ARBs  Spironolactone If patient doesn’t respond to first-line treatment, then give aldosterone antagonist – spironolactone as add-on therapy. It improves survival in chronic heart failure (RALES study) and contraindicated if hyperkalaemia or renal impairment Anti-hypertensive patients with resistant hypertension Steroid pro-drug has effect via Canrenone as Spironolactone has a half-life with 10 mins and Canrenone’s half-life with 9-16 hrs It blocks the aldosterone-induced production of sodium transport proteins in the DCT: It causes sodium and water loss & causes K+ retention It is a K sparring diuretic that inhibits action of aldosterone on collecting ducts and by themselves are weak diuretics, but important in sparring K+. It is often used in conjunction with Loop or Thiazide diuretics Ivabradine Used to treat angina (chest pain) & mild severe chronic heart failure as: it inhibits ionic current and reduces cardiac pacemaker activity, slows the HR and is alternative to beta blockers (may be used alongside this) Contraindications are MI, cardiogenic shock, heart block and slow heart rates Cautions are ineffective if atrial fibrillation present, elderly and angina Common side-effects are arrythmias, AV block, dizziness and headache Sacubitril Valsartan Combination of ARB and Sacubitril: Sacubitril (pro-drug) breakdown natriuretic peptides, increased peptides, natriuresis and vasodilation Used in patients not currently taking an ACE inhibitor or ARB Contraindications: systolic blood pressure should be lower than 100 mmHg Common side-effects: Anaemia, cough, diarrhoea, dizziness, electrolyte imbalance, headache, hypotension, syncope, vertigo, renal impairment and nausea  Hydralazine with Nitrate Patients who are intolerant to both ACEi’s and ARBs (African-Caribbean origin) and used to treat moderate and severe heart failure Venodilators are used to reduce pre-load and risk of pulmonary congestion Arterial vasodilators used to reduce after-load and increases stroke volume Contraindications are acute porphyrias; cor pulmonae, dissecting aortic aneurysm; poor cardiac function due to mechanical obstruction; tachycardia Common side-effects: angina, headaches, tachycardia, diarrhoea, dizziness, gastrointestinal disorders, hypotension, joint disorders, lupus-like syndrome Cautions: cerebrovascular or coronary artery disease Digoxin Mechanism of action: It blocks the Na+/K+ ATPase transporter, inhibiting the release of Na+ and causing a build-up of Ca2+ from the Na+/Ca2+ exchanger. This allows increased calcium stores and causes myofibril contraction, causing muscle contraction – to treat heart failure Originally known as an antiarrhythmic drug that increases parasympathetic neurons causing an increase in vagal tone to the heart, has a positive inotrope, which increases intracellular Ca2+ Indications of use: Chronic heart failure  improves symptoms but not mortality rates, supraventricular arrhythmias and chronic atrial fibrillation.  What is digoxin’s pharmacokinetics, contraindications and cautions Orally administered and bioavailability ~75%, onset of action ~30 mins, peak effect (IV) is 1-5 hrs, Half-life is 36 hrs, Elimination ~70% renal (GFR), VD640L/ 70Kg  binds to the skeletal muscle. Narrow therapeutic range and has a risk of toxicity Common side-effects: arrhythmias, cardiac conduction problems, cerebral impairment, dizziness, diarrhoea, nausea, skin reactions, vision disorders and vomiting Cautions: risk of digitalis toxicity with electrolyte imbalances and recent MI  Treatment for type 2 diabetes & heart failure Mechanism: blocks SGLT2 glucose transporter in the renal PCT, this causes glucosuria & fluid loss. SGLT2 inhibitors It causes haemodynamic changes reduces pre-load and after-load  cardiac function -- Dapagliflozin improves Adverse effects: rare severe ketoacidosis Contra-indications: diabetic ketoacidosis Cautions: elderly, hypotension, risk of volume depletion