Congestive Cardiac Failure or Congestive Heart Failure (CHF)

Objective

At the end of this PDF Notes, student will be able to

•       Define  congestive heart failure

•       Discuss the types of congestive heart failure

•       Explain the pathophysiology of congestive heart failure

•       Discuss the signs and symptoms of it

CONGESTIVE CARDIAC FAILURE

•      Congestive Heart Failure (CHF), often simply referred to as heart failure, is a chronic and potentially life-threatening medical condition that affects the heart’s ability to pump blood effectively. Despite its name, CHF doesn’t mean that the heart has stopped working, but rather that it’s struggling to meet the body’s demands for oxygen and nutrients. In this article, we’ll explore CHF in detail, including its causes, symptoms, diagnosis, treatment, and ways to manage this condition effectively.

•     A clinical syndrome

•      Result from any disorder that impairs the ability of the ventricle to fill with or eject blood

•      Rendering the heart unable to pump blood at a rate sufficient to meet the metabolic demands of the body

•       Heart failure can result from any disorder that reduces ventricular filling (diastolic dysfunction) and/or myocardial contractility (systolic dysfunction)

Causes of CHF: CHF is typically a result of underlying heart conditions, including coronary artery disease, high blood pressure, heart valve disease, cardiomyopathy, or congenital heart defects. Other factors like diabetes, obesity, and smoking can also contribute to its development.

Mechanism of CHF: CHF occurs when the heart’s chambers become weakened or stiff, making it difficult for the heart to fill with blood or pump blood effectively. This can lead to a buildup of fluid in the lungs and other parts of the body.

Common Symptoms of CHF:

Shortness of Breath: People with CHF often experience breathlessness, especially during physical activity or when lying down.

Fatigue: Feeling tired or fatigued, even after minimal exertion, is a common symptom.

Swelling: Swelling in the legs, ankles, or abdomen is frequently observed in CHF patients due to fluid retention.

Rapid or Irregular Heartbeat: Arrhythmias or irregular heartbeats may be present in individuals with CHF.

Reduced Exercise Tolerance: CHF can limit a person’s ability to engage in physical activities and exercise.

Etiology of Congestive Heart Failure

Systolic dysfunction (decreased contractility)

•       Reduction in muscle mass (e.g. myocardial infarction)

•       Dilated cardiomyopathies

•       Ventricular hypertrophy

•       Pressure overload (e.g. systemic or pulmonary HT, aortic or pulmonic valve stenosis)

•       Volume overload (e.g., valvular regurgitation, shunts, high-output states)

Diastolic dysfunction (restriction in ventricular filling)

•       Increased ventricular stiffness

•       Ventricular hypertrophy (e.g. hypertrophic cardiomyopathy)

•       Infiltrative myocardial diseases (e.g. amyloidosis, sarcoidosis, endomyocardial fibrosis)

•       Myocardial ischemia and infarction

•       Mitral or tricuspid valve stenosis

•       Pericardial disease (e.g. pericarditis, pericardial tamponade)

Types of Heart Failure

•       Acute and chronic heart failure

•       High output and low output HF

•       Left sided, right sided and biventricular HF

•       Forward and backward HF

•       Systolic and diastolic HF

Acute heart failure 

•       Heart is not able to pump the blood effectively

•       Also called as Decompensated heart failure

•       Compensatory mechanisms  of human body cause increase in CO by stimulation of β₁  receptors and also RAA-system

•       Both mechanism leads to vasoconstriction

•       Treatment with Inotropic drugs becomes necessary

Chronic heart failure

•       Failure of compensatory mechanism

•       Heart needs to undergo surgery for its repair

•       Further controlled by administration of drugs

High output HF:

•       There is high demands of the body, which are not met even with increased cardiac output

•       e.g.: anemia, pregnancy

Low output HF:

•       There is decreased contractility of heart leading to decreased cardiac output

•       e.g.: cardiomyopathy, valvular disease

Left sided (left ventricular) HF

•        Excess fluid accumulates upstream

•        Reduction in left ventricular output

•        Increase in left atrial pressure

•        Increase in pulmonary venous pressure

Ø  Acute increase in left atrial pressure causes pulmonary congestion and pulmonary edema e.g.: MI

Ø   Gradual increase in left atrial pressure causes reflex pulmonary hypertension but no pulmonary edema

e.g. : aortic stenosis

Right sided (right ventricular) HF:

•         Excess fluid accumulates upstream behind the failing right ventricle

•         Reduction in right ventricular output

•         Results in systemic venous congestion

Ex: pulmonary valvular stenosis, multiple pulmonary emboli

Systolic HF:

•       Characterized by an abnormality of ventricular contraction

•       As seen in ischemic heart failure and dilated cardiac myopathy

Diastolic HF:

•       Characterized by an impaired ventricular relaxation

•       Increased ventricular stiffness resulting in diastolic dysfunction

e.g.: ischemia, left ventricular hypertrophy

Pathophysiology of Congestive Heart Failure

Preload: Pressure that fills the left ventricle during diastole

•      Main Determinant– left ventricular compliance and venous return

•      Small increase in end-diastolic volume

•      large increase in cardiac output

•      Primary compensatory mechanism in normal heart

•      Ability of heart to alter the force of contraction depends  on preload

Afterload: Pressure against which the left ventricular contracts and is measured as the mean aortic pressure

• Main determinants – total peripheral resistance and left ventricle size
• Left ventricular dysfunction – an inverse relationship exist between afterload and stroke volume
• An increase in afterload causes a decrease in stroke volume

Key components of the pathophysiology of cardiac remodelling

Compensatory Mechanisms

Cardiac compensatory mechanism:

Ø  Ventricular dilation

Ø  Ventricular hypertrophy

Peripheral compensatory mechanisms:

Ø  Increased sympathetic activity

Ø  Activation of renin angiotensin aldosterone system

Ø   Increased release of arginine vasopressin

Renin Angiotensin Aldosterone system

Clinical Presentation – Signs of Congestive Heart Failure

•       Pulmonary edema

•        Pleural effusion

•        Tachycardia

•        Cardiomegaly

•       Peripheral edema

•        Jugular venous distension

•        Hepatojugular reflux

•        Hepatomegaly

Symptoms of Congestive Heart Failure

•          Dyspnea

•       Orthopnea

•       Paroxysmal nocturnal dyspnea

•        Exercise intolerance

•        Tachypnea

•       Ascites, Mental status changes

•       Cough

•        Fatigue

•        Nocturia

•        Hemoptysis

•        Abdominal pain, Anorexia, Nausea, Bloating

Diagnosis and Evaluation:

Medical History: A doctor will start by taking a thorough medical history to understand symptoms, risk factors, and potential causes.

Physical Examination: A physical examination will assess vital signs, signs of fluid retention, and abnormal heart sounds.

Imaging Tests: Diagnostic tests like echocardiography, X-rays, or cardiac MRI can provide images of the heart’s structure and function.

Blood Tests: Blood tests are used to assess kidney and liver function, as well as check for specific markers related to heart failure.

Treatment Options:

Lifestyle Changes: Managing CHF often involves adopting a heart-healthy lifestyle, which includes dietary changes, regular exercise, smoking cessation, and stress management.

Medications: Medications like diuretics, ACE inhibitors, beta-blockers, and others may be prescribed to alleviate symptoms and improve heart function.

Medical Devices: In some cases, medical devices such as pacemakers, implantable cardioverter-defibrillators (ICDs), or ventricular assist devices (VADs) may be recommended.

Surgery: Surgical interventions like coronary artery bypass grafting (CABG) or heart valve repair or replacement may be necessary in certain cases.

Prognosis:

Prognosis Varies: The prognosis for CHF can vary widely based on factors like the cause of heart failure, its severity, and how well it’s managed. With appropriate care, many people with CHF can lead fulfilling lives.

Progression Management: Although CHF is a chronic condition, its progression can often be slowed or stabilized with treatment and lifestyle changes.

Prevention:

Managing Risk Factors: Preventing CHF involves managing risk factors such as high blood pressure, diabetes, obesity, and coronary artery disease through lifestyle changes and regular medical check-ups.

SUMMARY

•       CHF is a clinical syndrome that impairs the ability of the ventricle to fill with or eject blood

•       Heart is unable to pump blood at a rate sufficient to meet the metabolic demands of the body

•       It can be classified as:  Acute and chronic heart failure,

•       High output and low output heart failure,

•       Left sided, right sided and biventricular heart failure,

•       Systolic and diastolic heart failure

Congestive Heart Failure (CHF) PDF Notes Download

FAQ: