Prognosis of diastolic dysfunction: difference in renal function

BackgroundDespite the common finding of diastolic dysfunction with preserved ejection fraction on routine echocardiography in elderly patients, it is unknown why some patients with isolated diastolic dysfunction are asymptomatic, whereas others develop diastolic heart failure (i.e. signs and symptoms of congestive heart failure).AimThe aim of the study is to investigate whether the intrinsic renal insufficiency turn diastolic dysfunction symptomatic.Patients and methodsWe reviewed 80 consecutive patients undergoing transthoracic echocardiography and divided them into two groups: group A, which included 40 patients with diastolic dysfunction without symptoms of heart failure, and group B, which included 40 patients with diastolic dysfunction and symptoms of heart failure. Patient's age, weight and cardiovascular risk factors (hypertension, diabetes and coronary artery disease) were recorded. We used Framingham criteria for congestive heart failure to determine the presence of diastolic heart failure from the symptoms developed, examination findings and radiological studies. Average creatinine clearance and estimated glomerular filtration rate were calculated for each group.ResultsThere was difference neither in age or sex nor in the echocardiographic variables of diastolic function or left ventricular hypertrophy between groups. Multiple regression analysis showed that only lower levels of creatinine clearance (74 ± 46 vs. 44 ± 36 ml/min, P = significant) and lower estimated glomerular filtration rate (69 ± 28 vs. 44 ± 33 ml/min/m΂, P = significant) were associated with diastolic heart failure. There was no significant difference in the presence of hypertension, diabetes and coronary artery disease between two groups.ConclusionThe results of this study support the hypothesis that patients with normal left ventricular ejection fractions but with diastolic dysfunction develop congestive heart failure because of underlying renal insufficiency. However, a larger prospective study is required to confirm this hypothesis.