Systolic vs Diastolic Dysfunction




General Considerations

  • Heart failure­ is defined as the inability of the heart to provide sufficient output to meet the metabolic demands of the body.
  • Heart failure may be classified by symptom severity (NYHA classification) and by stage of evolution (ACC/AHA classification).
  • Heart failure may also be classified by type of dysfunction (systolic vs. diastolic) and by the side of the heart affected (right vs. left).
  • The terms used to classify heart failure are not mutually exclusive – the conditions may be present at the same time (e.g. left heart failure with diastolic dysfunction, right heart failure with systolic dysfunction).
  • There may be overlap within categories (e.g. heart failure with systolic and diastolic dysfunction, biventricular heart failure).
  • The most common cause of right-sided heart failure is left-sided heart failure.

Comparison of Dysfunctions

  • The terms “systolic dysfunction” and “diastolic dysfunction” refer to abnormalities in the mechanical function of the heart during contraction and relaxation. In the context of heart failure, the terms represent clinical syndromes that include the signs and symptoms of heart failure (e.g. systolic heart failure, diastolic heart failure).
  • Systolic dysfunction
  • Impaired myocardial contractility
  • S3 gallop on auscultation
  • Low ejection fraction (EF)
  • Thin or weak heart muscle due to:
  • Ischemic heart disease
  • Chronic hypertension
  • Dilated cardiomyopathy
  • Myocarditis
  • Diastolic dysfunction
  • Impaired ventricular filling/relaxation
  • S4 gallop on auscultation
  • Normal ejection fraction
  • Stiff or thick heart muscle due to:
  • Hypertension with left ventricular hypertrophy (LVH)
  • Restrictive cardiomyopathy
  • Hypertrophic cardiomyopathy
  • Fibrosis
  • Amyloidosis
  • Sarcoidosis
  • Constrictive pericarditis
  • Hemochromatosis
  • Valvular disease
  • Aging