Acquired Heart Disease and Congestive Heart Failure

What is the definition of congestive heart failure?

What are the three factors that determine stroke volume?

What is the main cause of congestive heart failure in a child under 1 year old?

What is the main cause of congestive heart failure in a child over 1 year old with no congenital anomaly?

Which of the following is not a symptom of systemic venous congestion in congestive heart failure?

What is the main mechanism by which the heart is unable to maintain adequate cardiac output in congestive heart failure?

What is a common presenting symptom of heart failure in neonates and infants?

Which diagnostic tool is used to assess heart chamber sizes and myocardial function accurately?

What is the main function of Digitalis in the treatment of heart failure?

Which of the following is NOT a part of the '4D's' approach to treating heart failure?

What does Furosemide (Lasix) do in the treatment of heart failure?

When should an apical pulse be taken in relation to the administration of Digoxin?

Congestive Heart Failure (CHF)

Defined as a pathophysiologic state in which the heart is unable to pump blood at a rate commensurate with the body's metabolic needs.
Inability to dispose of systemic or pulmonary venous return adequately, or a combination of both.
Characterized by the heart's inability to maintain an adequate cardiac output.

Factors Affecting Cardiac Output

Preload: volume of blood in the ventricle at the end of diastole.
Afterload: pressure required to push blood into the arteries.
Contractility: ventricles' ability to squeeze.

Clinical Manifestations

Systemic Venous Congestion:
- Weight gain
- Hepatomegaly
- Edema
- Jugular vein distention
Pulmonary Venous Congestion:
- Tachypnea
- Dyspnea
- Cough
- Wheezes

Compensatory Response

Tachycardia
Cardiomegaly
Diaphoretic
Fatigue
Failure to grow

Assessment

Clinical history:
- Neonates and infants: poor feeding, tachypnea, cold sweat on forehead, poor weight gain
- Older children: fatigue, exercise intolerance, dyspnea, puffy eyes and pedal edema, growth failure

Diagnostics

Chest x-ray:
- Cardiomegaly
- Pulmonary edema
ECG:
- Arrhythmias
Echocardiogram:
- Assesses heart chamber sizes, measures myocardial function accurately, diagnoses congenital heart defects
Pulse-oximetry, CBG, hyperoxia test, CBC, U&A, calcium, creatinine, LFT, thyroid function

Treatment

Correct underlying causes of HF
The 4D's:
- Diet (low salt, high calories)
- Digitalis (improves cardiac contractility)
- Diuretics (reduces preload)
- Dilators (reduces afterload)
General Care:
- Rest
- Oxygenation
- Small frequent feeding
- Diet modification (sodium and fluid restriction)
Treatment of underlying cause:
- Repair of congenital defects (VSD, ASD)
- Heart transplantation

Medications

Diuretics:
- Furosemide (Lasix)
- Spironolactone/Aldactone
Digitalis:
- Digoxin
Dilators:
- ACE
- Hydralazine
- Nitroprusside
- Captopril

Digoxin Therapy

Increases the force of the myocardial contraction
Take an apical pulse with steth for 1 full min before every dose of digoxin
If bradycardia is detected, withhold digoxin dose

This quiz covers the pathophysiology of congestive heart failure, focusing on the heart's inability to pump blood adequately. It discusses the differences in causes between individuals under 1 year old with congenital disorders and those over 1 year old with acquired heart disease.