Diastolic
heart failure occurs when the heart does not
completely relax before it fills up with blood between heartbeats. This can
result in blood that backs up into the lungs and the rest of the body. Experts
know less about the treatment of diastolic heart failure than systolic heart
failure for two reasons:
- It is hard to define diastolic heart failure
precisely.
- Few clinical trials have found clearly effective
strategies for treating diastolic heart failure.
The most common cause of diastolic heart failure is left ventricular
hypertrophy caused by ongoing high blood pressure (hypertension). In this
condition, the heart muscle thickens in response to higher-than-normal blood
pressure in the arteries. This results in a smaller filling chamber in the
heart and therefore a diminished ability of the heart to fill with blood. The
heart also may not relax properly, which also affects how well the left
ventricle fills.
The best therapy for diastolic heart failure caused by left
ventricular hypertrophy is to treat the high blood pressure. Your doctor will
usually prescribe drug treatment for diastolic heart failure itself only after
treatment of its underlying cause is not effective in relieving
symptoms.
Since no standard drug combinations exist for diastolic heart
failure, your doctor will use your symptoms as a guide in choosing your drugs.
Beta-blockers, calcium channel blockers, diuretics, and angiotensin-converting
enzyme (ACE) inhibitors all have some ability to decrease symptoms in some
people.
Beta-blockers and calcium channel blockers.
One of the main causes of diastolic dysfunction is that the heart does not have
enough time to relax and fill before pumping blood out to the rest of your
body. Beta-blockers and certain calcium channel blockers decrease your heart
rate and allow more time for your heart to fill before pumping out blood with
each beat. Another benefit of these medicines is that they also effectively
reduce your blood pressure. This change can both slow and reverse the tendency
of your heart muscle to thicken.
Diuretics. Just as in people with systolic
heart failure, diuretics can improve symptoms in people with diastolic heart
failure by removing excess fluid from the body. There is a delicate balance
between too little removal of fluid and thus incomplete relief of symptoms and
too much removal of fluid, which can lead to an increased heart rate and heart
function that is worse.
ACE inhibitors. Some recent evidence suggests
that this class of medicine can significantly improve symptoms in people with
diastolic heart failure. This may be because these agents can lower the blood
pressure and because of direct effects these medicines have on the heart
muscle, both of which can lead to less thickening of the heart muscle and
improved diastolic function.