Congestive Heart Failure

Heart Failure

Failure of the heart to perform its functionResults from deficiency in the heart's function

as a pump, where the delivery of blood, and therefore oxygen and nutrients, becomes inadequate for the needs of the tissues.

Causes

• The common underlying aetiologies in patients with heart failure are coronary artery disease and hypertension.

• Identifiable causes of heart failure include aortic stenosis, cardiomyopathy, mechanical defects such as cardiac valvular dysfunction, hyperthyroidism and severe anaemia.

Types of Heart failure

Systolic failureReduced mechanical pumping activity

(contractility)

Diastolic Pressure(paki move dun ←)Stiffening and loss of adequate relaxation of ventricle

playing a major role in reducing filling and cardiac output.

• Left-sided heart failure– left ventricle does not contract sufficiently to

pump the blood returned from the left atrium and lungs into the aorta, causing excessive amounts of blood to remain in the lung tissue. The patient usually has SOB and dyspnea.

Types of Heart failure

Types of Heart failure

• Right-sided heart failure– The heart does not sufficiently pump the blood

returned into the right atrium from the systemic circulation. As a result, the blood and its constituents are backed into peripheral tissues causing peripheral edema.

Classification

Clinical Manifestations• S/Sx:– reduced cardiac output,– impaired oxygenation– fatigue– Shortness of breath occurs on exertion (dyspnoea)– Orthopnoea– Paroxysmal nocturnal dyspnoea– Patients with heart failure may appear pale and their

hands cold and sweaty.– Reduced blood supply to the brain and kidney can cause

confusion and contribute to renal failure, respectively.– Oedema affects the lungs, ankles and abdomen.– The sputum may be frothy and tinged red from the

leakage of fluid and blood from the capillaries.

Primary Signs and Symptoms Associated with all types of CHF (uncompensated): severity

depends on the degree of CHF

Clinical Manifestations

• Laboratory Tests– Atrial natriuretic hormone• Reference Value: 20-77ng/L• ANH is secreted from the atria and acts as an

antagonist to renin and aldosterone• It is released during expansion of the atrium, produces

vasodilation and increases GFR.

• Laboratory Tests– Brain natriuretic peptide• Reference values: Desire value: <100pg/mL : Positive value: .100pg/mL• BNP test aids in the diagnosis of heart failure• Considered to be more sensitive test than ANP for

diagnosing HF.

Clinical Manifestations

Diagnosis• Blood test– The following assessments are usually performed:

• Blood gas analysis to assess respiratory gas exchange• Serum creatinine and urea to assess renal function• Serum alanine- and aspartate-aminotransferase plus

other liver function tests• Full blood count to investigate possibility of anaemia• Thyroid function tests to investigate possibility of

thyrotoxicosis• Serum BNP or NT pro-BNP to indicate likelihood of a

diagnosis of heart failure (screening test)• Fasting blood glucose to investigate possibility of diabetes

mellitus

Diagnosis• 12-lead electrocardiogram– A normal ECG usually excludes the presence of left

ventricular systolic dysfunction. An abnormal ECG will require further investigation

• Chest radiograph – A chest radiograph (X-ray) is performed to look for an

enlarged cardiac shadow and consolidation in the lungs

• Echocardiography – An echocardiogram is used to confirm the diagnosis of

heart failure and any underlying causes, for example, valvularheart disease

Desired Outcome

The aims of drug treatment are to control symptoms and to improve survival. By slowing disease progression the aim is to maintain quality of life.

Pharmacologic Treatment

Pharmacologic TreatmentDRUG COMMENT

Thiazide• Bendroflumethiazide•Metolazone

effective in the treatment of sodium and water retention, although there is generally a loss of action in renal failure (GFR <25 mL/min). Metolazonehas an intense action when added to a loop diuretic and is effective at low GFR

Loop•Furosemide•Bumetanide•Torasemide

Loop diuretics are preferred in the treatment of sodium and water retention where renal dysfunction is evident or more severe grades of heart failure present.Agents can be given orally or by infusion, and all are effective at low GFR

DRUG COMMENT

Aldosterone antagonist•Spironolactone

Can enhance diuretic effect of loop and/or thiazide. Due to slow onset of action needs 2–3 days before maximum diuretic effect reached. Spironolactone can improve survival when given as an adjunct to ACE inhibitor and diuretic therapy at a recommended dose of 25 mg daily (initial dose of 25 mg daily or onalternate days)

Aldosterone antagonist•Eplerenone

In early post-MI patients with symptomatic heart failure (or asymptomatic patients with diabetes mellitus), eplerenone 50 mg daily improved survival when added to optimal therapy (initial dose of 25 mg daily)

DRUG COMMENT

ACE inhibitorCaptopril EnalaprilLisinoprilRamipril TrandolaprilCilazaprilFosinoprilPerindoprilQuinapril

First-dose hypotension may occur. May worsen renal failure. Adjust dose in renal failure. Hyperkalaemia, cough, taste disturbance and hypersensitivity may occur particularly with captopriL.

B-BlockerCarvedilolBisoprolol

May initially exacerbate symptoms but if initiated at low dose and slowly titrated can improve long-term survival, even in elderly patients with heart failure .

Half-life of nebivolol can be 3–5 times longer in slow metabolisers

DRUG COMMENT

NitratesGlyceryl trinitrate Isosorbide dinitrate Isosorbidemononitrate

Isosorbide dinitrate metabolised to isosorbide mononitrate. High doses needed. Tolerance can be prevented by nitrate-free period of >8 h. Protective effect against cardiac ischaemia. GTN given intravenously for sustained effect in acute/severe heart failure but limited by tolerance.

Nitroprusside Light sensitive. Acts on veins and arteries. Cyanide accumulation and acidosis limit treatment duration

DRUG COMMENT

Angiotensin II receptor blockerLosartan Candesartan Valsartan

Comparable effectiveness to ACE inhibitor in patients with ACE inhibitor intolerance, although similar effect on renal function and blood pressure. Recent evidence suggests improved survival when ARB used as adjunctive therapy. However, increased potential fordeterioration in renal function and/or hyperkalaemia

Hydralazine Hydralazine has a direct action on arteries. Tolerance occurs. May cause drug-induced lupus and sodium retention

DRUG COMMENTCardiac glycosidesDigoxin Digitoxin

In renal failure, half-life of digoxin is prolonged. Dosage individualisationrequired. Serum drug concentration monitoring used to confirm or exclude toxicity or effectiveness. CNS,visual and GI symptoms linked to digoxin toxicity. No benefit in terms of mortality, but use associated with improved symptoms and reduced hospitalisation for heart failure. Beneficial in AF, although risk of arrhythmias with high doses.

Phosphodiesterase inhibitorsEnoximoneMilrinone

Used only in severe heart failure as adjunctive therapy. Associated witharrhythmias and increased mortality with chronic use

SOAPPP

Plan

• Pharmacologic

• Non-pharmacologic– Limit salt intake to 2g (approx. 1 tsp)– Excessive alcohol use can lead to cardiomegaly,

therefore alcohol should be avoided.– Avoid smoking for it deprives the heart of oxygen.– Obesity increases CV problems, Pt should be in

low fat and low calorie diet.