Left Ventricular Failure

• LVF:

  • hyper-perfusion of the preceding pulmonary circulation
  • hypo-perfusion of the succeeding systemic circulation
  • patients symptoms reflect this abnormal blood distribution
• Clinical Presentation of LVF will be secondary to varying degrees of:

  • pulmonary hyper-perfusion e.g. cardiogenic pulmonary oedema - interrupting starlings forces, promoting oedema
  • systemic hypo-perfusion e.g. inadequate cardiac output
• LVF:

  • hyper-perfusion effects pt1:
  • impaired gas exchange - pulmonary congestion raises hydrostatic pressure at capillary level, within pulmonary capillaries, pushes fluids out of the capillary walls into the surrounding tissue spaces, and where this fluid is pushed out at alveolar level, there is pulmonary oedema, increasing diffusion distance, impairing gas exchange
  • dyspnoea (NYHA class 2 to 4) - due to impaired gas exchange secondary to pulmonary oedema, which also reduces compliance and increases work of breathing, generating higher levels of inspiratory force in order to inflate the lungs
  • orthopnoea - breathlessness when lying flat due to change in relationship with gravity causing redistribution of blood throughout the body, increasing volume of blood sitting within the central body zone, increasing central venous pressure, increases venous return, which is another challenge for the heart to cope with
• LVF:

  • hyper-perfusion effects pt2:
  • paroxysmal nocturnal dyspnoea - lying flat during the night causing redistribution of blood flow centrally overwhelming the heart, causing pulmonary congestion which causes sudden breathlessness, waking pts up
  • pulmonary crackles due to fluid in the lungs
  • pulmonary oedema
  • coughing with frothy sputum
  • pleural effusions
  • wheezy
• LVF:

  • hypo-perfusion causes:
  • reduced cardiac output to the systemic arterial system
• LVF:

  • hyper-perfusion causes:
  • pulmonary congestion
• LVF:

  • hypo-perfusion effects:
  • fatigue / decreased exercise tolerance - due to reduce cardiac output to the systemic arterial system, causing organs to be under-perfused, especially the skeletal muscle -> lack of oxygen to muscle causes fatigue and decreased exercise tolerance
  • dyspnoea - low cardiac output increases respiratory rate
  • confusion - low cardiac output decreases blood flow to the brain
• On chest x-ray you may see:

  • cardiomegaly - an enlarged heart
  • pulmonary oedema
  • pleural effusions
• LVF:

  • can occur in children and babies as well as adults, e.g. babies born with congenital heart disease such as holes in the heart, in the septum between atrium, in the septum between ventricles (ASD, VSD, AVSD)