Echocardiographic Longitudinal Strain Analysis in Heart Failure: Real Usefulness for Clinical Management Beyond Diagnostic Value and Prognostic Correlations? A Comprehensive Review.

Heart failure (HF) is a highly prevalent clinical syndrome characterized by considerable phenotypic heterogeneity. The traditional classification based on left ventricular ejection fraction (LVEF) is widely accepted by the guidelines and represents the grounds for patient enrollment in clinical trials, even though it shows several limitations. Ejection fraction (EF) is affected by preload, afterload, and contractility, it being problematic to express LV function in several conditions, such as HF with preserved EF (HFpEF), valvular heart disease, and subclinical HF, and in athletes. Over the last two decades, developments in diagnostic techniques have provided useful tools to overcome EF limitations. Strain imaging analysis (particularly global longitudinal strain (GLS)) has emerged as a useful echocardiographic technique in patients with HF, as it is able to simultaneously supply information on both systolic and diastolic functions, depending on cardiac anatomy and physiology/pathophysiology. The use of GLS has proved helpful in terms of diagnostic performance and prognostic value in several HF studies. Universally accepted cutoff values and variability across vendors remain an area to be fully explored, hence limiting routine application of this technique in clinical practice. In the present review, the current role of GLS in the diagnosis and management of patients with HF will be discussed. We describe, by critical analysis of the pros and cons, various clinical settings in HF, and how the appropriate use and interpretation of GLS can provide important clues.

Left atrial remodeling in heart failure: the role of sphericity index (the SPHERICAT-HF study).

Left atrial sphericity index (LASI) is an echocardiographic index easily obtained; its use in patients with heart failure (HF) has never been investigated so far. This single-centre study aimed to investigate the usefulness of LASI in an unselected cohort of patients hospitalized for acute HF, and its potential correlation with the amino-terminal portion of pro-B-type natriuretic peptide (NT-proBNP) levels and with New York Heart Association (NYHA) functional class. Ninety-four consecutive HF patients underwent a transthoracic echocardiogram with a detailed study of the left atrium (LA) including LASI (calculated from the apical four-chamber view as the ratio between the transverse and longitudinal diameters), and blood tests (including NT-proBNP) on the same day. Median age was 75.5 (interquartile range-IQR 62-82) years and 55% were males, 58.5% had a NYHA class III-IV, and median NT-proBNP was 3284 (IQR 1215-7055) pg/ml. The LA was dilated in 94%, and median biplane LA volume index was 62 ml/m2. Patients with advanced NYHA class showed more advanced LA remodeling. Mean LASI was 0.78 ± 0.09 and did not correlate with NT-proBNP levels (r 0.03; p 0.75) or with patient NYHA class (R2 0.011; p 0.287). None of the echocardiographic indices of LA structural and functional remodeling proved to be independently associated with a high NYHA class on multivariate regression analysis. In conclusion, LA remodeling is almost invariably present in patients with HF. LASI does not correlate with NT-proBNP levels or with NYHA functional class. Further studies are needed to describe the complex patterns of atrial remodeling in HF.

Left bundle branch block-induced cardiomyopathy: a diagnostic proposal for a poorly explored pathological entity.

Despite being increasingly recognized as a specific disease, at the present time left bundle branch block (LBBB)-induced cardiomyopathy is neither formally included among unclassified cardiomyopathies nor among the acquired/non-genetic forms of dilated cardiomyopathy (DCM). Currently, a post-hoc diagnosis of LBBB-induced cardiomyopathy is possible when evaluating patients' response to cardiac resynchronization therapy (CRT). However, an early detection of a LBBB-induced cardiomyopathy could have significant clinical and therapeutic implications. Patients with the aforementioned form of dyssynchronopathy may benefit from early CRT and overall prognosis might be better as compared to patients with a primary muscle cell disorder (i.e. "true" DCM). The real underlying mechanisms, the possible genetic background as well as the early identification of this specific form of DCM remain largely unknown. In this review the complex relationship between LBBB and left ventricular non-ischaemic dysfunction is described. Furthermore, a multiparametric approach based on clinical, electrocardiographic and imaging red flags, is provided in order to allow an early detection of the LBBB-induced cardiomyopathy.