In recent years, a "new" type of heart problem has become commonly diagnosed by cardiologists, called diastolic dysfunction. When diastolic dysfunction becomes severe, diastolic heart failure can occur.
Neither diastolic dysfunction nor diastolic heart failure are really "new" - these conditions have been around forever. But it has only been in the last decade or two, since echocardiography has been widely used to diagnose heart problems, that these conditions have become commonly recognized.
The diagnosis of diastolic dysfunction is now made quite frequently, especially in older women, most of whom are shocked to hear they have a heart problem at all. While some of these patients will go on to develop actual diastolic heart failure, many will not - especially if they get appropriate medical care and take care of themselves.
Still, it is now thought that almost half the patients who come to emergency rooms with episodes of acute heart failure actually have diastolic heart failure.
But the diagnosis can be tricky, because once the patient presenting with diastolic heart failure has been stabilized, the heart can appear entirely normal on the echocardiogram - unless the doctor looks specifically for evidence of diastolic dysfunction. For this reason, the diagnosis of diastolic heart failure can be missed by unwary physicians.
What Is Diastolic Dysfunction and Diastolic Heart Failure?
The cardiac cycle is divided into two parts - systole and diastole. During systole, the ventricles (the heart's major pumping chambers) contract, thus ejecting blood out of the heart and into the arteries. After the ventricles have finished contracting, they relax. During this relaxation phase they re-fill with blood to prepare for the next contraction.
This relaxation phase is called diastole.
Sometimes, however, due to various medical conditions, the ventricles become relatively "stiff" Stiff ventricles cannot fully relax during diastole; as a result, the ventricles may not fill completely and blood can "dam up" in the body's organs (mainly the lungs). An abnormal stiffening of the ventricles and the resulting abnormal ventricular filling during diastole are referred to as diastolic dysfunction.
When diastolic dysfunction is sufficient to produce pulmonary congestion (that is, a damming up of blood into the lungs), diastolic heart failure is said to be present.
In general, when doctors use the terms diastolic dysfunction and diastolic heart failure, they are referring to isolated diastolic abnormalities - there is diastolic dysfunction without any evidence of systolic dysfunction. ("Systolic dysfunction" is just another name for a weakening of the heart muscle, which occurs in the more typical forms of heart failure.)
What Causes Diastolic Dysfunction?
Diastolic dysfunction can be produced by several medical conditions, including:
- high blood pressure
- hypertrophic cardiomyopathy
- aortic stenosis
- coronary artery disease
- restrictive cardiomyopathy
- aging (Whether age itself causes stiffening of the ventricles, or whether such stiffening is related to some other medical condition associated with aging, is not yet understood.)
Diagnosing and Treating Diastolic Dysfunction and Diastolic Heart Failure
Here is additional information on diastolic dysfunction and diastolic heart failure:
Gutierrez C, Blanchard DG. Diastolic Heart Failure: Challenges of Diagnosis and Treatment. American Family Physician. 69:11. 2004. Available at:http://www.aafp.org/afp/20040601/2609.html.