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• Congestive heart failure (CHF)


  A clinical syndrome in which the heart is unable to pump enough blood to the body to meet its needs, to dispose of systemic or pulmonary venous return adequately, or a combination of the two
• Pathophysiology of CHF


  1. Systemic oxygen transport = product of cardiac output and systemic oxygen content

  2. Cardiac output = product of heart rate and stroke volume

  3. Primary determinants of stroke volume are afterload, preload, and contractility
• Frank-Starling law


  • As the ventricular end-diastolic volume (or preload) increases, the healthy heart increases cardiac output until a maximum is reached and cardiac output can no longer be augmented
  • When the left ventricular (LV) end-diastolic pressure reaches a certain point, pulmonary congestion develops with pulmonary congestive symptoms (tachypnea and dyspnea)
• Compensatory mechanisms to adapt to chronic heart failure

  1. Increase in sympathetic tone secondary to increased epinephrine and norepinephrine

  2. Decreased blood flow to the kidneys marked increase in renin output increase angiotensin II
• Increase in angiotensin II


  Increase in reabsorption of both water and salt from the renal tubules, may cause a trophic response in vascular smooth muscle (with vasoconstriction) and myocardial hypertrophy, promotes myocardial fibrosis which is maladaptive response
• Causes of CHF by age


  • In utero/fetal: Severe anemia, Supraventricular tachycardia, severe Ebstein anomaly, myocarditis
  • Premature neonate: Fluid overload, PDA, VSD
  • Full-term neonate: Asphyxial cardiomyopathy, AV malformation, coarctation of aorta, hypoplastic left heart syndrome
  • Infant-toddler: L to R shunts (VSD)
  • Child-adolescent: Rheumatic fever, myocarditis, hypertension
• Clinical manifestations of CHF in infants

  • Feeding difficulties and poor weight gain
  • Excessive perspiration
  • Irritability
  • Tachypnea & signs of RD, wheezing
  • Hepatomegaly
  • Cardiomegaly
  • Gallop rhythm
  • Auscultatory finding produced by the underlying cardiac lesion
  • Edema may be generalized and usually involves the eyelids as well as the sacrum and less often the legs and feet
• Clinical manifestations of CHF in children

  • Fatigue & effort intolerance
  • Anorexia
  • Abdominal pain
  • Cough,dyspnea and orthopnea
  • Elevated jugular venous pressure
  • Gallop rhythm is common
  • Hepatomegaly
  • Edema in dependent portions of the body, or anasarca may be present
  • Cardiomegaly is invariably noted
• Chest X-ray show cardiac enlargement and pulmonary vascularity
• ECG show chamber hypertrophy helpful in assessing the cause of heart failure but does not establish the diagnosis
• Echocardiographic are most useful in assessing ventricular function and also diagnose the underlying problem
• Treatment of CHF


  1. Elimination of the underlying causes e.g. surgical management of CHD, valve repair

  2. Treatment of the precipitating or contributing causes (e.g.infection, anemia, arrhythmias, fever,hypertension)

  3. Control of the heart failure state
• Control of the heart failure state

  1. General supportive measures: Rest till out of failure, Oxygen administration, Increase daily calorie intake, Control salt intake older children "no added salt" diets

  2. Diuretics: reduce preload and improve congestive symptoms but do not improve cardiac output or myocardial contractility

  3. Inotropic agents: digoxin, dopamine, dobutamine

  4. Afterload reducers: ACE inhibitors, Arteriolar vasodilators (hydralazine), Venodilators (nitroglycerin, isosorbide dinitrate)

  5. Other drugs: β-Adrenergic Blockers