Heart failure with normal ejection fraction or HFnlEF is the term used when symptoms and signs of heart failure occur due to diastolic dysfunction in the presence of normal systolic function.

Nomenclature

Both diastolic heart failure and heart failure with normal ejection fraction (HFnlEF) are used, though some argue that the latter term is better.

Epidemiology

HFnlEF accounts for 50 percent of heart failure cases.

With age, the prevalence of HFnlEF increases more rapidly than that of HF with reduced EF (HFrEF). HFrEF is more in males while HFnlEF is more in females.

 Natural history

Mortality and morbidity of HFnlEF are almost comparable to those of HFrEF.

 Clinical features

Symptoms and signs are same as those in heart failure with reduced ejection fraction. The major and minor criteriae of Framingham are satisfied here also. No clinical feature can reliably distinguish HFnlEF from HFrEF, only imaging studies can do this.

 Patients are usually older than 65 years. Majority are females (2/3). Majority are hypertensives (2/3). In fact, hypertension is the most common associated condition in patients with HFnlEF. Nearly half are obese (40%). Nearly half are diabetic also (40%).

Atrial fibrillation is seen in 1/3 rd cases. HFnlEF may cause AF which, in turn, causes clinical deterioration.

Causes

The main causes are old age, hypertension, diabetes, obesity and renal disease. Other causes include HCM, idiopathic restrictive cardiomyopathy, amyloidosis, radiation heart disease (pericardial and myocardial restriction) and constrictive pericarditis.

Although acute ischemia is known to cause diastolic dysfunction, the role of stable coronary artery disease in contributing to HFnlEF remains speculative.

Echo

LV size is normal. LA is enlarged. Significant PAH is present in half cases. 

LVH is present in less than half cases.

Exercise testing

This is useful to diagnose exaggerated hypertensive response to exercise which can cause diastolic dysfunction. Such patients have dyspnoea on exertion due to hypertension, but resting echo studies show normal diastolic function.

BNP

BNP is increased, but not as much as with HFrEF.

Therapy

Diuretics are useful to control pulmonary congestion and peripheral edema.

Exercise is beneficial and should be promoted.

Hypertension, if present, should be controlled.

Atrial fibrillation, if present, should be controlled.

Myocardial ischemia, if thought to be contributory, should be dealt with.

 Trials

CHARM preserved trial- candesartan was useful.

Statins may be useful.

SENIORS trial- nebivolol was not proven to be useful.

DIG trial- digoxin was not useful.

PEP-CHF trial- perindopril was not useful.

I-PRESERVE trial-  Irbesartan was not useful.

Ongoing trials-

            Sitaxsentan sodium, endothelin antagonist

            Hong Kong Diastolic Heart Failure Study- combinations of diuretics, ramipril, and irbesartan

            TOPCAT – aldosterone antagonists

            Use of Nesiritide in the Management of Acute Diastolic Heart Failure trial- nesiritide