Introduction
Congestive Cardiac Failure (CCF), commonly called heart failure, occurs when the heart is unable to pump enough blood to meet the body’s needs. The failure may occur in the right ventricle, left ventricle or both. Due to weak pumping action, the movement of blood becomes slow, and pressure inside the heart increases. The heart muscle tries to compensate by stretching or thickening, but over time these mechanisms fail. As the heart weakens further, the kidneys retain more salt and water, causing swelling (edema) in legs, feet, lungs and other organs. This makes the body congested, which is why the condition is called congestive cardiac failure.
CHF is usually a chronic condition and represents the final stage of various heart diseases.
Definition
Heart failure is a progressive clinical syndrome in which the heart is unable to pump sufficient blood to meet the body’s metabolic demands. This may be due to reduced filling of the ventricles (diastolic dysfunction) or reduced pumping ability (systolic dysfunction).
Etiology (Causes)
Common causes include:
- Coronary artery disease leading to heart attack
- Heart muscle weakness due to viral infections or toxins like alcohol
- Heart valve diseases
- Long-standing hypertension
Less common causes include viral myocarditis, amyloidosis, HIV cardiomyopathy, connective tissue disorders, drug toxicity (e.g., chemotherapy), arrhythmias and metabolic disorders.
Classification
1. Systolic Heart Failure
The pumping ability of the left ventricle is weak. Ejection fraction (EF) falls below 55%. The heart cannot eject sufficient blood.
2. Diastolic Heart Failure
The heart contracts normally but becomes stiff and cannot fill properly. EF remains normal or even increased. More common in elderly individuals, especially women with hypertension.
3. Acute Heart Failure
Develops suddenly, often after a major heart attack, myocarditis or valve rupture. Presents with rapid fall in cardiac output, hypotension and shortness of breath without edema.
4. Chronic Heart Failure
Develops slowly due to long-standing hypertension, valvular disease or chronic lung disorders. Blood pressure is usually maintained but edema is common.
Pathophysiology
Heart failure develops due to one or more of the following mechanisms:
1. Intrinsic Pump Failure
- Ischemic heart disease
- Myocarditis
- Cardiomyopathy
- Metabolic disorders like beriberi
- Rhythm disorders such as atrial fibrillation
2. Increased Workload on the Heart
Pressure Overload:
- Systemic or pulmonary hypertension
- Valvular stenosis (mitral, aortic, pulmonary)
- Chronic lung diseases
Volume Overload:
- Valvular insufficiency
- Severe anemia
- Thyrotoxicosis
- Arteriovenous shunts
- Lung diseases causing hypoxia
3. Impaired Filling of the Heart
Occurs in pericardial diseases or conditions restricting ventricular filling.
Signs and Symptoms
Left Ventricular Failure
- Breathlessness (dyspnea) due to pulmonary congestion
- Orthopnea: difficulty breathing while lying down
- Paroxysmal nocturnal dyspnea: sudden breathlessness at night
- Tachycardia
- Enlarged heart
- Mitral regurgitation due to dilated ventricles
- Atrial fibrillation due to enlarged left atrium
- Cyanosis and acidosis in advanced stages
- Ventricular arrhythmias leading to sudden death
Fluid Retention and Swelling
- Edema in legs, ankles and feet
- Pitting edema visible on pressing the swollen area
- Severe cases show swelling up to hips, abdomen (ascites)
- Sudden weight gain due to fluid accumulation
Right-Sided Heart Failure (from Additional Information)
- Fluid buildup in abdomen, legs and feet
- Swelling (edema) and enlarged liver
Diagnosis
- Laboratory Tests: CBC, electrolytes, kidney and liver function tests, thyroid profile, urinalysis, lipid profile, HbA1c.
- BNP Test: BNP levels above 100 pg/mL suggest heart failure.
- Chest X-ray: Shows enlarged heart, pleural effusion or pulmonary edema.
- ECG: Detects ventricular hypertrophy or rhythm abnormalities.
- Echocardiogram: Determines ejection fraction and identifies structural abnormalities.
Symptoms of Heart Failure (Additional)
- Shortness of breath (especially during activity or lying down)
- Chronic cough or wheezing
- Swelling in legs, ankles and abdomen
- Fatigue and weakness
- Dizziness or confusion
- Rapid or irregular heartbeat
- Weight gain from fluid retention
Pathogenesis
In early stages, three compensatory mechanisms help maintain heart function:
- Sympathetic stimulation increases heart rate and contractility but raises workload.
- Sodium and water retention increases blood volume to stretch heart muscles and improve contraction.
- Myocardial hypertrophy increases muscle mass to strengthen contractions.
However, long-term activation of these mechanisms leads to worsening heart failure.
When pulmonary capillary pressure rises above 25–40 mmHg, fluid leaks into lung spaces, causing pulmonary edema and severe breathlessness.
Causes of Heart Failure (Detailed)
- Coronary artery disease
- Heart attack
- Cardiomyopathy from infections, alcohol or drugs
- Hypertension
- Valve diseases
- Thyroid and kidney diseases
- Diabetes
- Arrhythmias (fast or slow heartbeats)
- Congenital heart defects
- Myocarditis
Complications
- Kidney damage: Reduced blood flow can lead to kidney failure.
- Arrhythmias: Irregular heartbeats may develop and can be life-threatening.
- Liver damage: Fluid buildup causes liver congestion leading to scarring.
Detailed Notes:
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