Heart Failure Quiz

• Heart failure (HF) is an abnormality of cardiac structure or function that prevents the heart from ejecting or filling properly resulting in dyspnea, fatigue, weakness, and circulatory congestion.

• Chronic HF develops or progresses slowly with common vascular congestion, arterial pressure is well maintained until very late.

• Exacerbations in chronic HF are often precipitated by infection, tachycardia, non-compliance with medications, emotional stress, and arrhythmias.

• Refractory HF does not respond adequately to usual treatment.

Forms of HF include:

• Systolic failure: ventricle cannot contract normally, leading to inadequate cardiac output and an ejection fraction <40%.

• Diastolic failure: ventricle cannot relax and fill normally, leading to elevated filling pressures and an ejection fraction >50%.

• Systolic and diastolic failure often coexist in HF patients.

• Low-output HF: cardiac output at rest is <2.2 L/min per m² and exertion does not increase it.

• Low-output HF can occur after myocardial infarction (MI), hypertension, dilated cardiomyopathy, and valvular or pericardial disease, and often involves vasodilation and warm extremities.

• High-output HF: cardiac output is >3.5 L/min per m² usually with underlying heart disease; seen in hyperthyroidism, anemia, pregnancy, arteriovenous fistulas, beriberi, and Paget's disease.

• Left-sided HF: left ventricle is hemodynamically overloaded, leading to pulmonary congestion (dyspnea, orthopnea).

• Right-sided HF: abnormality primarily affecting right ventricle, resulting in edema, congestive hepatomegaly, and systemic venous distention.

Epidemiology

• HF affects about 4.5 million people in the U.S.
• Approximately 0.5 million new cases are diagnosed per year, with 1 million hospital admissions and >50,000 deaths annually.
• The condition is increasingly prevalent in North America and Europe, commonly affecting the elderly.
• Diastolic HF is more common in women, especially elderly women with hypertension.

Risk Factors

• Include hypertension, coronary artery disease, diabetes mellitus, dilated or hypertrophic cardiomyopathy, valvular heart disease, and cardiotoxins

Etiology

• Ventricles respond to chronic hemodynamic overload by developing hypertrophy
• Chronic pressure overload causes concentric ventricular hypertrophy, increasing the ratio between wall thickness and ventricular cavity size.
• Elevated stroke volume over long periods causes the ventricle to dilate and develop eccentric hypertrophy, maintaining a relatively constant ratio between wall thickness and ventricular cavity diameter
• Cardiac function may remain stable for years, progression of HF is initially slow, then accelerates.
• Ultimately deterioration of myocardial function leads to HF: the ventricle dilates; the ratio between wall thickness and cavity size decreases, endogenous neurohormonal systems are activated, cytokines appears to be involved.

Symptoms & Signs

• Symptoms include dyspnea with exertion, orthopnea (dyspnea when recumbent, relieved by sitting upright), paroxysmal nocturnal dyspnea (severe shortness of breath and coughing at night), fatigue and weakness, abdominal symptoms (anorexia, nausea, abdominal pain), cerebral symptoms (altered mental status due to reduced cerebral perfusion), and nocturia

Physical Findings

• Include pulmonary rales with possible expiratory wheeze, lower-extremity edema, hydrothorax (pleural effusion), ascites (common in constrictive pericarditis and tricuspid valve disease), congestive hepatomegaly, positive abdominojugular reflux, jugular venous distention, third and fourth heart sounds, elevated diastolic arterial pressure
• Findings in late/severe HF also include pulsus alternans, diminished pulse pressure, jaundice, decreased urine output, and cardiac cachexia.

Differential diagnosis

• Considers pulmonary disease with dyspnea, obstructive airway disease, diffues parenchymal lung disease, pulmonary vascular occlusive disease, chest wall and respitory muscles as well as cardiac asthma

Diagnostic Approach

• Includes detailed clinical examination, two-dimensional echocardiography with Doppler flow studies, electrocardiography (ECG), chest radiography, and brain natriuretic peptide (BNP) measurement.

• Framingham criteria for diagnosing congestive heart failure (CHF) requires at least 1 major and 2 minor criteria

Major Criteria

Includes paroxysmal nocturnal dyspnea, neck vein distention, rales, cardiomegaly, acute pulmonary edema, S3 gallop, increased venous pressure, and positive hepatojugular reflux

Minor Criteria:

• Include extremity edema, night cough, dyspnea on exertion, hepatomegaly, pleural effusion, vital capacity reduced by one-third from normal, and tachycardia (≥120 beats/min), weight loss ≥4.5 kg over 5 days of treatment.

Laboratory Tests:

• ECG aids in determining etiology such as abnormal Q waves in old MI, left venticular hypertrophy in hypertension. BNP measurement:
• A level >200 pg/mL supports diagnosis
• A level <40 pg/mL rarely seen in HF
• Useful in diagnosis, prognosis, and monitoring therapy
• Helps in differentiating between cardiac and pulmonary causes of dyspnea

Labs Continued

• Urinalysis: albuminuria, high specific gravity, low sodium level.
• Renal function: Prerenal azotemia
• Electrolytes abnormalities
• Hypokalemia from thiazide diuretics
• Hyperkalemia from potassium-retaining diuretics
• Dilutional hyponatremia in late HF
• Liver Function Testing
• Hepatic enzymes; frequently elevated
• Elevated direct and indirect bilirubin level (late finding)

Imaging

• 2-dimensional echocardiography with Doppler flow

• Determine underlying causes

• Assess severity of ventricular systolic and/or diastolic dysfunction, valvular dysfunction

• Question diagnosis if all cardiac chambers normal in volume, shortening and wall thickness

• Chest radiography detect cardiomegaly and pulmonary congestion

Diagnostic Procedures

• ECG rarely normal in systolic HF

Classification

• Stage A: At high risk for HF, but no evident structural heart disease or symptoms of HF - Examples include hypertension, coronary artery disease, and diabetes mellitus
• Stage B: Structural heart disease without symptoms of HF - examples include Previous MI, Left ventricular systolic dysfunction, Asymptomatic valvular disease as well as Dilated, hypertrophic, or restrictive cardiomyopathy
• Stage C: structural heart disease with prior or current symptoms of HF such as Shortness of breath, Fatigue, and Reduced exercise tolerance
• Stage D: Refractory HF requiring specialized intervention, marked symptoms at rest despite maximal medical therapy

Treatment Approach

• Stage A: treat hypertension, perscribe an ACE inhibitor, encourage smoking cessation, treat lipid disorders, encourage regular exercise, discourage alcohol intake and illicit drug use
• Stage B: All measures under stage A, add beta-blocker
• Stage C: All measures under stage A and B, add diuretic, add digitalis in systolic HF, add spironalactone, restrict dietary salt to <2 g/d
• Stage D: All measures under stages A, B, and C, dietary salt restriction to <1 g/d, mechanical assist devices, heart transplantation, continuous intravenous inotropic infusions for palliation, hospice care

Specific Treatments

• Treat hypertension treat lipid disorders, encourage smoking cessation, discourage alcohol intake and illicit drug use, recommend influenza and pneumococcal vaccines. Achieve optimal weight with Regular isotonic exercise in compensated HF

• In moderately severe chronic HF: additional rest on weekend, scheduled naps or rest periods, avoidance of strenuous exertion and avoid temperature extremes and tiring trips.

Diet

• Reduce sodium intake (normal diet contains 6–10 g of sodium daily
• Intake can be halved by excluding salt-rich foods and eliminating table salt.
• Can be reduced to one-quarter with the above measures and omitting salt from cooking
• In severe HF: limit to 1 g/d
• Late in course: often, both sodium and water intake must be restricted.

Thiazides

• Indications: Use thiazides alone in mild Stage C HF and in combination with other diuretics in late, severe Stage C HF or Stage D
• Side effects:
• Hypokalemia
• Hyponatremia
• Metabolic alkalosis
• Fatigue
• Lethargy
• Reduced excretion of uric acid or hyperuricemia
• Impaired glucose tolerance
• Rashes
• Thrombocytopenia
• Granulocytopenia
• Specific agents
• Hydrochlorothiazide
• Dosage: 25 mg/d to 25 mg qid
• Chlorthalidone
• Convenient
• Most widely used long-acting thiazide Dosage: 50-100 mg/d

Loop Diuretics

• Indications for loop diuretics all forms of HF, particularly in patients with severe or refractory HF and pulmonary edema

• Side effects; Metabolic alkalosis, Hypokalemia, Hyperuricemia, Hyperglycemia, Weakness, Nausea, and Dizziness

• Specific agents: Furosemida, IV: initial dose, 20 mg (maximum, 80 mg) as well as PO: initial dosage, 20-40 mg 1-2 times daily (maximum, 400 mg/d)

• Bumetanidea, IV: initial dose, 0.5 mg (maximum, 2 mg), PO: initial dosage, 0.5-1.0 mg 1-2 times daily (maximum, 10 mg/d)

• Torsemidea, IV: initial dose, 5 mg (maximum, 20 mg), PO: initial dosage, 10 mg 1-2 times daily (maximum, 200 mg/d)

Other Diuretics

• Metolazonea; Dosage: 2.5 mg 1-2 times daily and with Actions indications similar to thiazides

• Spironolactonia; Dose 12.5-25 mg/d, use with a loop diruetic, monitor Potassium level, has many effects

• Side effects: -Weak diuretic, but is used for prolonging life -Hyperkalemia, Nauseaa -_Epigastric distress -Mental confusion, Renal failure -Monitor Potassium for potassium level must be >5, Hyponatremia

ACE inhibitors

• Have a central role in treatment
• Do not use in hypotenstive pregnant patients Side effects:
• Cough Angioneurotic edema Leukopenia Teratogenic effects in first trimester Specific agents: Enalapril maleate - 2.5 mg Fosinopril sodium - 5-10 mg Lisinopril - 2.5-5.0 mg Quinapril hydrochloride - 10 mg Ramipril 1.25-2.5 mg

Angiotensin Receptor Blockers

• Indications for angiotensin receptor blockers
• Intolerance to ACE inhibitors

Beta Blockers

• indications for beta blockers: patients in Stage C HF
• Contraindications Unstable HF, O Hypotension, O Severe fluid overload.
• 15% of patients (cannot tolerate beta blockade)
• Metoprolol CR - 1.25-25

Digoxin : Indications for digoxin Systolic HF complicated by atrial flutter and fibrillation and rapid ventricular rate

• Indications for digoxin reduced in HF with sinus rhythm , systolic HF Oral dosage

Vasodilators

• Other vasodilators
• Chronic HF with systemic vasoconstriction despite ACE inhibitor therapy

Ventricular resynchronization (biventricular pacing)

• Indication for chronic HF with impaired intraventricular conduction (O) *Increases distance

Management of Arrhythmias

• Electrolyte balance
• Correction of electrolyte and acid-base disturbances (especially hypokalemia and digitalis intoxication)
• Amiodarone; class - drug of choice in HF with atrial fibrillation

Anticoagulants

Warfarin may be given -May be indicated in severe HF

Heparin, Atrial fibrillation, previous venous thrombosis, HF and

Refractory HF

Combinations of different diuretics Left ventricular or biventricular pacing

Monitoring- BNP

• Prognosis Severe depressed Frequent extrasystoles

Test your knowledge of heart failure, including systolic vs diastolic failure, exacerbation management, high-output vs low-output failure, and diagnostic criteria.