Introduction:The maximal rate of change of pressure-normalised wall stress dσ*/dtmax has been proposed as cardiac index of left ventricular (LV) contractility. In this study, we assessed the capacity of dσ*/dtmax to diagnose heart failure with normal ejection fraction (HFNEF).Materials and Methods: One hundred healthy normal controls and 140 patients admitted with heart failure (100, HFREF and 40, HFNEF) underwent echocardiography for stress-based contractility dσ*/dtmax. Patients with significant valvular heart disease were excluded. Tissue Doppler indices were also measured. Results:dσ*/dtmaxwas 4.43 ± 1.27 s-1 in control subjects; reduced in HFNEF, 3.02 ± 0.98 s-1; and HFREF, 2.00 ± 0.67 s-1 (P <0.001). In comparison with age- and sex-matched groups (n = 26 each), we found similar trend on reduction of dσ*/dtmax (normal control; 3.91 ± 0.87 s-1; HFNEF, 2.90 ± 0.84 s-1; HFREF, 1.84 ± 0.59 s-1, P <0.001). On multivariate analysis, dσ*/dtmax was found to be the independent predictor of HFNEF and HFREF. The area under the curve of the receiver operating characteristics (ROC) in detecting HFNEF compared with normal controls (dσ*/dtmax >3.2 s-1) was 0.84 (P <0.0001), and in detecting HFREF compared with HFNEF (dσ*/dtmax >2.32 s-1) was 0.88 (P <0.0001). Conclusion: This data confirms that dσ*/dtmax on echocardiography is a powerful independent predictor in patients with HFNEF. In a population with a high suspicion of HFNEF, dσ*/dtmax may significantly contribute to early diagnosis and hence be useful in the triage and management of HFNEF patients.
Heart failure (HF) is a major health care burden: it is the leading cause of hospitalisation in persons older than 65 years, and confers an annual mortality of 10%. HF can occur with either normal or reduced left ventricular (LV) ejection fraction (EF). Patients with heart failure with normal ejection fraction (HFNEF) generally have concentric LV remodeling with increased wall thickness (due to increased cardiomyocyte diameter and extracellular matrix collagen), whereas patients with HFREF often exhibit eccentric remodeling with an increase in end-diastolic volume (due to increased cardiomyocyte length). Both HF with normal EF (HFNEF) and HF with reduced EF (HFREF), also commonly known as diastolic and systolic HF, respectively, have equally poor prognosis. Many studies have reported that various systolic function indices are mildly depressed in patients with HFNEF. Abnormalities demonstrated include a reduction in long-axis shortening, a decline in systolic velocity of basal myocardial and mitral valve annular motion and abnormalities of both strain and strain rate. Indeed, it is well recognised that impairments in myocardial contractility may coexist with HFNEF. A novel LV contractility index, dσ*/dtmax (maximal rate of change of pressure-normalised wall stress) was previously validated11 and used in recent study. The objective of this study is to establish the clinical utility of dσ*/dtmax as a tool for diagnosis of HFNEF.
This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.