Heart Failure: An Overview

Heart failure is a complex syndrome that occurs when the heart cannot pump enough blood to meet the body’s needs. The main cause is a decline in the contractile function of the left ventricle and neurohormonal dysregulation, leading to a loss of exercise capacity.

Types of Heart Failure

• Systolic Heart Failure: Occurs when the contractile ability of the left ventricle decreases, often with an ejection fraction (EF) <= 40%.

• Diastolic Heart Failure: Occurs when the ability of the left ventricle to relax and fill with blood is restricted, often with an EF >= 50%.

Additionally, heart failure can be classified based on its severity:

• Acute Heart Failure: Occurs suddenly, often due to significant damage to a portion of the heart wall, leading to hemodynamic disturbances.

• Chronic Heart Failure: Develops gradually, often due to the heart’s compensatory mechanisms, such as dilation or hypertrophy of the heart chambers.

Causes of Heart Failure

• Systolic Heart Failure: Due to a decrease in the contractile function of the ventricle.

• Diastolic Heart Failure: Due to impaired ventricular relaxation, leading to a reduced time for ventricular filling.

• Acute Heart Failure: Due to significant damage to a portion of the heart wall, leading to hemodynamic disturbances.

Symptoms of Heart Failure

• Acute Heart Failure:

• Heart Rate (HR) is often rapid due to the inability of the ventricle to dilate or compensate with hypertrophy.

• Severity of Functional Class (FC) is high.

• Pulmonary edema is common.

• Peripheral edema is rare.

• Slight or no weight gain.

• Slight or no fluid overload.

• Enlarged heart is less common.

• Left ventricular systolic function may be decreased, normal, or hypercontractile.

• Increased wall stress.

• Chronic Heart Failure:

• HR is usually slow due to compensatory mechanisms like dilation or hypertrophy of the heart chambers.

• Severity of FC is mild to moderate.

• Pulmonary edema is rare.

• Peripheral edema is common.

• Weight gain is common.

• Fluid overload is common.

• Enlarged heart is common.

• Left ventricular systolic function is often decreased.

• Increased wall stress.

• Decompensated Chronic Heart Failure:

• Severity of FC is high.

• Pulmonary edema is common.

• Peripheral edema is common.

• Weight gain is common.

• Significant fluid overload.

• Enlarged heart is often present.

• Decreased left ventricular systolic function.

• Significantly increased wall stress.

Asymptomatic Left Ventricular Systolic Dysfunction (LVSD)

This refers to the presence of long-standing decreased ventricular contraction without any functional class symptoms.

Heart Failure with Low Ejection Fraction (Low EF)

• Characteristics:

• Most common heart condition.

• Characterized by a reduced EF.

• Easily assessed through echocardiography.

• Causes:

• Obstruction of the left ventricular outflow tract.

• Increased left ventricular volume.

• Damage to the left ventricular myocardium.

• FC:

• FC related to pulmonary congestion (dyspnea on exertion).

• FC related to low cardiac output (fatigue, dizziness).

Right Heart Failure

• Causes:

• Increased pressure load on the right ventricle.

• Increased right ventricular volume.

• Damage to the right ventricular myocardium.

• Symptoms:

• In some cases of left ventricular damage, symptoms may mimic right heart failure due to the bulging of the interventricular septum towards the right ventricle, reducing right ventricular filling.

• FC may include peripheral congestion (hepatomegaly, jugular vein distention).

Risk Factors for Heart Failure

• Underlying factors:

• Valvular heart disease (in younger individuals < 40 years old).

• Coronary artery disease, hypertension (in older individuals).

• Hypertrophic cardiomyopathy, restrictive cardiomyopathy (causing diastolic heart failure).

• Aggravating Factors:

• Non-compliance with treatment (medications, diet).

• Hemodynamic factors.

• Use of inappropriate medications (NSAIDs, calcium channel blockers).

• Infections.

• Anemia.

• Thyroid disease.

• Pulmonary embolism.

Functional Class (FC) of Heart Failure

• Due to pulmonary congestion:

• Dyspnea on exertion.

• Orthopnea.

• Paroxysmal nocturnal dyspnea.

• Acute pulmonary edema.

• Due to Low Cardiac Output:

• Fatigue, weakness.

• Nocturia.

• Cerebral FC (confusion, memory loss, anxiety, headache).

Determining Exertion Level in Dyspnea on Exertion

• Walking distance on flat ground.

• Number of flights of stairs climbed.

Note: Dry cough in heart failure patients is considered “equivalent to dyspnea.”

Advice:

• If you experience any symptoms of heart failure, consult a doctor for prompt diagnosis and treatment.

• Adhere to treatment guidelines provided by your physician.

• Maintain a healthy lifestyle, including a balanced diet, regular exercise, and stress management.