updated July 5, 2006 - People think of heart failure as a condition where the heart does not pump out enough blood. That is called systolic heart failure. However, many CHFers have a different kind of heart failure - caused when the heart does not fully relax, so it does not fill properly with blood. This is called diastolic heart failure. This page is about diastolic heart failure or DHF.
In mild DHF, SOB and fatigue usually only happen during stress or activity. More severe DHF causes many of the same symptoms that systolic heart failure or SHF, causes.
A person with DHF has high pressures in the arteries of their lungs - pulmonary pressure. Their heart's pumping chambers may not be enlarged and their ejection fraction may be normal, but they still have the same nasty symptoms as a person with SHF.
In people with diastolic heart failure, Toprol-XL may be a better beta-blocker choice than Coreg. Too-low blood pressure can be a real problem for DHF patients. Toprol-XL does not lower blood pressure as much as Coreg.
How to always diagnose DHF accurately is uncertain but a correct diagnosis is important. Some guidelines propose that 3 requirements be met to make the call:
There are some situations where symptoms alone may lead to a misdiagnosis. This is especially true in older patients who get short of breath mainly because they have very poor physical fitness. It can also happen with non-heart-related shortness of breath such as with lung disease. So diagnosing DHF requires some signs or symptoms of CHF like lung congestion, edema, raised jugular vein, etc. You do have to rule out problems like mitral valve disease and and lung disease.
DHF cannot usually be distinguished from SHF by patient history, physical exam, x-ray, and EKG alone. Diagnosis requires an estimate of LV size and EF. These measurements can be made using echo, MUGA, or cath. Really, DHF diagnosis is a matter of ruling out other possible causes in patients seeming to have heart failure but who have normal heart size and EF.
Since echo does have limits for spotting DHF and cath is invasive, one trial studied whether the BNP blood test could help spot diastolic heart failure. That study is shown on the BNP Test page. It turns out that a quick BNP test can help a doctor diagnose DHF.
|Diagnosis: Systolic versus diastolic heart failure|
| Systolic Heart Failure - Reduced EF
| Diastolic Heart Failure - Normal EF
|Shortness of breath on exertion||85%||96%|
|Waking at night short of breath||55%||50%|
|Difficulty breathing except upright||60%||73%|
|Jugular vein swollen||35%||46%|
|Sounds in lungs||72%||70%|
|Point of maximum impulse||50%||60%|
|Enlarged (congested) liver||15%||16%|
|Heart enlargement on chest x-ray||90%||96%|
|High pulmonary (lung) pressures||75%||80%|
As many as 33% of patients with obvious heart failure and a normal EF may have DHF. Risk of DHF increases with age:
Prognosis of patients with DHF is better than for SHF. Annual mortality for DHF is about 5 to 8%, while it is about 10 to 15% for SHF. In healthy people of the same age, mortality is about 1%. In DHF patients, prognosis is also affected by cause. When CAD is not the cause, annual mortality is much better, at about 2% to 3%. Age also affects risk of death. The 5-year mortality rate in DHF patients is:
The complication rate is about the same as for SHF patients. DHF causes frequent outpatient visits and hospital admissions. The one year readmission rate is almost 50% in DHF patients.
Treatment guidelines for systolic heart failure are based on large, properly done trials. Unfortunately, no such trials exist for DHF. So guidelines come from small trials, a doctor's experience, and his understanding of the disease. The general approach to treating DHF has 3 main steps:
With some exceptions, many of the drugs used to treat systolic heart pressure are also used to treat diastolic heart failure. However, the reason they are used and the dose may be different for DHF.
For example, in DHF beta-blockers are used to make filling the heart with blood take longer, and to change the heart's response to exercise. In SHF, beta-blockers are used to increase pumping power and reverse heart remodeling. Diuretic dose for DHF is usually much smaller than for SHF. Calcium channel blockers have no place in SHF treatment but may help DHF.
The first step in treating DHF patients is to reduce lung congestion. You do that by lowering pulmonary (lung) pressure. This has 3 steps:
For these reasons, most doctors use beta-blockers and calcium channel blockers to slow the heart rate a lot in DHF patients. However, slowing the heart rate too much can reduce cardiac output despite better filling. This is why DHF patients need very individualized treatment. An initial goal might be a resting heart rate of about 60 beats per minute.
Beta-blockers and calcium channel blockers increase the time it takes the heart to fill with blood. This helps keep pulmonary pressures low. However, these drugs also directly reduce the heart's ability to relax by their effects at the cell level. It's a tricky balance to strike in DHF patients. The overall effect of these drugs in DHF patients is improved symptoms.
The long-term effect of calcium channel blockers on diastolic heart failure patients is unknown. All calcium channel blockers except amlodipine increase mortality in patients with systolic heart failure.
March 27, 2006 - A "third generation" (new) beta-blocker called Nebivolol is on the way. Nebivolol has the main good benefit of Toprol-XL (beta-1 blocking without beta-2 blocking) plus one of the good benefits of Coreg (relaxing the arteries, called vasodilation). It also helps endothelial function and is a powerful anti-oxidant. Nebivolol does this without all of Coreg's side effects.
Researchers studied how nebivolol affects systolic versus diastolic left heart function in patients. This substudy included 104 patients; 43 had an EF less than 36%. Echo was done on each patient to take quite a few heart measures at study start and again one year later.
In the group with EF less than 36%, nebivolol reduced heart size and improved EF 5%. Other measures remained the same. In patients with EF higher than 36%, no changes in the heart muscle were seen.
So in patients with weakly pumping hearts (low EF), nebivolol reduces heart size and improves EF. In patients with near-normal or normal EF (diastolic heart failure) no changes in the heart muscle were seen. None the less, risk of death or heart-related hospitalization improved in both groups in SENIORS.
The SENIORS trial showed that nebivolol reduces risk of death and heart-related hospitalizations in senior CHFers regardless of EF. What does this mean? It suggests that CHFers with diastolic heart failure may now have a drug proven to help them.
Jon's note : The average age in the SENIORS trial was 76 years.
Source: Eur Heart J. 2006 Mar;27(5):562-8. Epub 2006 Jan 27.
Title: Effects of nebivolol in elderly heart failure patients with or without systolic left ventricular dysfunction: results of the SENIORS echocardiographic substudy.
Authors: Ghio S , Magrini G , Serio A, Klersy C, Fucilli A, Ronaszeki A, Karpati P, Mordenti G, Capriati A, Poole-Wilson PA, Tavazzi L; SENIORS investigators. PMID: 16443607
Exercise in a healthy person makes the heart relax more quickly and lowers LV pressure faster. The heart muscle actually stretches and gets larger when full of blood just before pumping it out. This increases EF. In a healthy person, these actions help the body handle exercise.
In DHF, those actions are very limited. The heart's stiffness prevents it from stretching to increase its size when filled with blood. EF does not rise, and patients get short of breath and very tired. Often, there is quite a rise in blood pressure and heart rate during exercise. The rise in blood pressure makes the heart work harder, which screws up the entire pumping cycle.
These changes increase diastolic pressures. High diastolic pressures reduce lung function and make breathing harder. Low heart output during exercise causes fatigue in the legs and other muscles.
Small trials show that calcium channel blockers, beta-blockers, and ARBs improve exercise ability in many DHF patients. However, these drugs do not always improve heart function.
Use inotropic drugs with caution. Since ejection fraction is often okay in DHF patients, inotropes may give no benefit at all. However, such drugs can cause harm in these patients. Inotropic drugs may help in the short-term for lung congestion but even short-term use may cause ischemia, speed up heart rate, or trigger arrhythmias.
Digoxin (Lanoxin) strengthens the heart's pumping power. This increases energy demand, which may only show up during stress like exercise or ischemia, when digoxin can worsen diastolic function. With the exception of patients in chronic atrial fibrillation (to slow ventricular rate), digoxin is not recommended for DHF.
In CAD, treatment should aim to reduce the heart's oxygen demand and increase blood flow to the heart. Drugs like nitrates (nitroglycerine), calcium channel blockers, and beta-blockers have all been shown to help. Clearing blocked arteries with angioplasty or CABG may also help diastolic heart failure patients with CAD.
|Drug treatment of diastolic heart failure|
|Loop diuretics||Bumex (bumetanide), Lasix (furosemide), Demadex (torsemide)|
|Thiazide diuretics||Hygroton (chlorthalidone), Hydrodiuril, Esidrix (HCTZ, hydrochlorothiazide), Amiloride, Aldactone (spironolactone)|
|Long-acting nitrates||Isordil, Sorbitrate (Isosorbide Dinitrate), Imdur (Isosorbide mononitrate)|
|Beta-blockers||See this page|
|Calcium channel blockers||Norvasc (amlodipine), Cardizem (diltiazem), Isoptin (verapamil), Procardia (nifedipine)|
|RAS inhibitors||ACE inhibitors (see this page), ARBs (see this page), and aldosterone antagonists|
Title: Diastolic Heart Failure: Diagnosis and Treatment
Authors: Dr. Michael R. Zile, Dr. Janet M. Simsic
Source: Clinical Cornerstone 3(2):13-24, 2000
All information on this site is opinion only. All concepts, explanations, trials, and studies have been re-written in plain English and may contain errors. I am not a doctor. Use the reference information at the end of each article to search MedLine for more complete and accurate information. All original copyrights apply. No information on this page should be used by any person to affect their medical, legal, educational, social, or psychological treatment in any way. I am not a doctor. This web site and all its pages, graphics, and content copyright © 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Jon C.