Management of Heart Failure Dr Khulood Alsaraf

Heart Failure Heart failure is the progressive inability of the heart to supply adequate blood flow to vital organs. It is classically accompanied by significant fluid retention. It is a leading cause of mortality and morbidity.

Heart Failure The most common symptoms of CHF includes shortness of breath, edema and fatigue. Causes of heart failure includes : Coronary artery disease (CAD), Hypertension, Diabetes, Mitral valve disease and Chronic alcohol.

Manifestations

STAGE DISABILITY CLASS 1 MILD CLASS 2 CLASS 3 MODERATE CLASS 4 SEVERE No symptoms Can perform ordinary activities without any limitations CLASS 2 Mild symptoms - occasional swelling Somewhat limited in ability to exercise or do other energetic activities CLASS 3 MODERATE Noticeable limitations in ability to exercise or participate in mildly energetic activities Comfortable only at rest CLASS 4 SEVERE Unable to do any physical activity without discomfort, Some HF symptoms at rest

Heart Failure Compensatory Mechanisms Sympathetic over-activity Remodeling of cardiac tissue ( myocytes, hypertophy, & fibrosis ) Sympathetic over-activity Stimulation of renin-angiotensin - aldosterone & vasopressin release

Heart Failure

Heart Failure Treatment Goals 1- To alleviate symptoms 2- Slow disease progression 3- Improve survival

Drugs used in H.F

Drugs used in H.F ACE Inhibitors Angiotensin receptor blockers Direct Vasodilators Diuretics Beta blockers Aldosterone antagonists Inotropic agents

Drugs used in H.F Angiotensin Converting Enzyme Inhibitors : ACE inhibitors improve mortality, morbidity, exercise tolerance, left ventricular ejection fraction. Captopril , Enalopril , Lisinopril , Ramipril , Moexipril , Quinapril and Fosinopril

ACE Inhibitors

Drugs used in H.F Action of ACEIs Reduction in arterial resistance (afterload) Reduction in venous tension (preload) Reduction in aldosterone secretion Inhibition of cardiac and vascular remodeling ACEIs considered for single-agent therapy in patients who present with mild dyspnea on exertion and do not show sign and symptoms of volume overload (edema). They are indicated in patients with all stages of left ventricular failure.

Drugs used in H.F Angiotensin Converting Enzyme Inhibitors orally absorbed, should be taken on an empty stomach. Plasma T1/2 from 2-12 hrs. Compounds, such as Ramipril and Fosinopril require only once-a-day dosing. Adverse effects Dry irritating persistent cough Hyperkalemia Angioedema Fetal toxicity

Drugs used in H.F Angiotensin Receptor AT-1 blockers (ARBS) Irbesatan, Candesartan,Telmisartan, Olmesartan, Losartan,and Valsartan Competitive antagonists of Angiotensin II (AT-1). No inhibition of ACE or cough. Their use in HF is as substitute for ACEI in those patients with sever cough or angioedema. Effective orally and require only once a day dosing All are highly plasma protein bound (greater than 90%), except for Candesartan that have large volume of distribution.

Amlodipine and prazosin are other vasodilators can be used in HF. Drugs used in H.F Direct vasodilators : Isosorbide dinitrate and hydralazine also used specially in patients who cannot tolerate ACE inhibitors. Amlodipine and prazosin are other vasodilators can be used in HF. Dilation of venous blood vessels leads to a decrease in cardiac preload by increasing in venous capacitance. Nitrates are commonly used venous dilators for patient with CHF. Combination of hydralazine and isosorbide dinitrate is quite effective in black patients with HF. Hydralazine decreases afterload, organic nitrate reduces preload.

Drugs used in H.F Diuretics These are useful in reducing the symptoms of volume overload ( orthopnea and paroxysmal nocturnal dyspnea) by: decreasing the extra cellular volume decreasing the venous return to the heart (preload) Thus decreases cardiac workload and oxygen demand. Diuretic may also decrease afterload by reducing plasma volume, there by decreasing B.p.

Drugs used in H.F Diuretics Loop diuretics like furosemide and bumetanide are the most effective and commonly used. Thiazides are effective in mild cases only.

Drugs used in H.F Diuretics Adverse effects : Loop diuretics and thiazides cause hypokalemia. Potassium sparing diuretics help in reducing the hypokalemia due to these diuretics.

Drugs used in H.F β – blockers Antagonize the effect of norepinephrine on the cardiac muscle fibers, decreasing remodeling, hypertrophy, and cell death. Two β – blockers have been approved for use in HF: Carvedilol : nonselective β – adrenoreceptors antagonist that also blocks α – adrenoreceptors Metoprolol : long acting β1 – specific antagonist. Both of them reduce morbidity and mortality associated with HF. Treatment should be started at low doses and gradually titrated to effective doses based on patient tolerance.

Drugs used in H.F Aldosterone antagonists Spironolactone : Aldosterone inhibition minimize potassium loss, prevent sodium and water retention, endothelial dysfunction and myocardial fibrosis. Spironolactone is a direct antagonist of aldosterone, thereby preventing salt retention, myocardial hypertrophy and hypokalemia. Can be added to loop diuretics to modestly enhance the diuresis; more importantly, improve survival. Adverse effects 1- gastric disturbances such as peptic ulcer 2- CNS effects such as confusion 3- endocrine abnormality such as gynecomastia and menstrual irregularities

Drugs used in H.F Inotropic Agents 1- Cardiac glycoside ( digoxin ) 2-Dobutamine 3-Milrinone & Inamrinone

Drugs used in H.F 1-Cardiac glycosides Digoxin : Inhibition of Na/K ATPase pump increase intracellular sodium concentration – eventually increase cytosolic calcium. It restores the vagal tone and abolishes the sympathetic over activity. Increase the refractoriness of AV node thus decrease ventricular response to atrial rate. Digoxin is used as a first-line drug in patients with congestive heart failure who are in atrial fibrillation.

Drugs used in H.F 1-Cardiac glycosides Digoxin : Indicated in patient with sever left ventricular systolic dysfunction after initiation of ACEI and diuretic therapy. It is not indicated in patients with diastolic or right side HF. It is very potent with narrow margin of safety and long half life of around 36 hrs. A loading dose regimen is used when acute digitalization is needed. It is mainly eliminated by the kidney, requiring dose adjustment based on creatinine clearance.

Digoxin in CCF Effect of Digoxin

Drugs used in H.F Digoxin Adverse effects Contraindications Nausea, vomiting, gynecomastia, visual disturbances and psychosis. Contraindications Obstructive cardiomyopathy HF due to carditis Heart block Severe stenotic lesion Electroconversion Wolf Parkinsonian White syndrome

Drugs used in H.F Digoxin toxicity treatment 1- Decontamination/enhanced elimination 2-Fab fragments of digoxin-specific antibodies digoxin immune fab (ovine) 3- Activated charcoal 4- Treatment of arrhythmias 5- Treatment of electrolyte imbalance

Drugs used in H.F 2-Dobutamine Is a beta-1 agonist which increase cardiac contractility and cardiac output. It is the most commonly used inotropic agent other than digoxin. No change in the heart rate. Given I.V infusion in case of acute HF in a hospital setting.

Drugs used in H.F 3-Milrinone & Inamrinone Phosphodiesterase III Inhibitors Increase intracellular Ca++ Positive inotropic agent( increase cardiac contractility) Minimal change in HR & BP Increase COP Milrinone & Inamrinone long term therapy may be associated with increase in the risk of mortality