Last year, I wrote about heart failure. At that time, I had said that about half the patients admitted with congestive heart failure have normal systolic function. This is true.
The most common way to express heart function is by measuring ejection fraction (EF). This is the proportion of the amount of blood in the left ventricle in diastole (after it fills) that is ejected.
So, why would someone have normal function and have heart failure?
Some common reasons would be valve problems, age, obesity, atrial fibrillation, coronary artery disease, etc.
One big explanation is that the ventricle is thickened and stiff. This may not be the only cause, but it is relatively easy to understand. Filling in diastole is impaired. Hypertension is one cause, as are old age and obesity.
The big key many times is in making the diagnosis because these patients have so many other reasons for breathlessness. Also, most of the blood tests and other cardiac tests are not always useful.
So, it is a diagnosis that often is made by cardiologists based on suspicion and the constellation of supportive test data.
How is treatment different compared to patients with decreased function?
For starters, for reduced EF, many treatments are proven to work. For heart failure with preserved function, there are not that many proven therapies. However, there are some treatment goals.
Assessing blockages, good blood pressure and diabetes control, weight loss, exercise and diet control are known to help. Diuretics in patients with fluid overload, treatment of sleep apnea, and restoring normal rhythm are also key.
Some devices like pulmonary artery sensors are useful in monitoring fluid status/preventing fluid buildup and hospitalization. Some medicines have been shown to work especially in preventing admission. Some of these include diuretics like Aldactone and medicines like Entresto. However, unlike in patients with reduced EF, these are useful in only select groups of patients and not all patients with preserved EF. Therefore, it is important to see a specialist who deals with this issue.