The epidemiological enigma of heart failure with preserved systolic function.
BACKGROUND
Current epidemiological evidence suggests that the prevalence of preserved systolic function in patients with heart failure varies widely from 13 to 74%. This inconsistency suggests a lack of consensus as to what this condition really is and how it has been characterised for epidemiological studies.


OBJECTIVE
In this review, we summarise and discuss the current understanding of the epidemiology of heart failure with preserved systolic function and the challenges that this raises.


METHODS
Studies were identified from Medline and Embase Literature Database searches using the subject headings heart failure, diastolic heart failure, epidemiology, incidence, prevalence, diagnosis, prognosis and mortality.


RESULTS
Sixty-one studies of congestive heart failure with preserved systolic function were reviewed. There is great diversity in the criteria used to determine whether heart failure is present, the patient population, the setting of the study and methods of evaluating left ventricular function. This makes epidemiological studies of prevalence, morbidity and mortality impossible to compare.


CONCLUSIONS
The diagnosis of this syndrome might be better defined in terms of symptoms, elevated neuro hormones and impaired cardiac workload. This would allow accurate identification of cases so that further research could be conducted to measure outcome and assess therapeutic benefit.
Cardiovascular Medicine, National Heart and Lung Institute, Imperial College, Charing Cross Campus, Fulham Palace Road, London SW3 6LY, UK. s.graves@imperial.ac.uk
Martin D
MD
Thomas
Kevin F
KF
Fox
Andrew J S
AJ
Coats
George C
GC
Sutton
D001794:Blood Pressure / Q000502:physiology*; D003971:Diastole; D006333:Heart Failure / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology*; D006801:Humans; D009017:Morbidity; D015995:Prevalence; D011379:Prognosis; D013599:Systole