The Kidney in Diastolic Dysfunction

More than 5 million people in the United States have a diagnosis of heart failure (HF). More than 650,000 new cases are diagnosed annually, with an associated mortality of 50% within 5 years from first diagnosis. Although HF with reduced ejection fraction (EF) has been well studied, HF with preserved EF (EF > 50%), also referred to as diastolic HF (DHF), has been identified only recently as a clinical pathology, despite the fact that it accounts for half of all HF cases and is responsible for the majority of hospital admissions related to HF. Recent studies indicate that the incidence of DHF is increasing and that a greater portion of patients hospitalized with HF have a diastolic dysfunction (DD). According to the American College of Cardiology Foundation/American Heart Association task force, DHF may be defined as including the following: (1) clinical signs or symptoms of HF; (2) evidence of preserved or normal left ventricle (LV) EF; and (3) evidence of abnormal LV DD that can be determined by Doppler echocardiography or cardiac catheterization. Higher age, obesity, coronary artery disease, diabetes mellitus, atrial fibrillation (AF), and hyperlipidemia have a high prevalence in patients with DHF, whereas hypertension is the most frequent of them with a prevalence of 60% to 89%. DD may appear many years before any symptom develops and may represent the first phase of DHF. Therefore it is important to detect DD early and to start treatment as soon as possible after diagnosis. DD and DHF are systemic disorders rather than an isolated cardiac disorder. Distal organ effects, with particular focus on kidney function, are addressed in this chapter.