Early Left Ventricular Dysfunction and Non-Dipping: When Ejection Fraction is Not Enough. A Meta-Analysis of Speckle tracking Echocardiography Studies

Abstract

Background and Aim There is evidence that a reduced nocturnal fall in blood pressure (BP) entails an increased risk of hypertensive-mediated organ damage (HMOD) and cardiovascular events. Most studies focusing on left ventricular (LV) systolic function, assessed by conventional LV ejection fraction (LVEF) in non-dippers compared to dippers failed to detect significant differences. To provide a new piece of information on LV systolic dysfunction in the non-dipping setting, we performed a meta-analysis of speckle tracking echocardiography (STE) studies investigating LV global longitudinal strain (GLS), a more sensitive index of LV systolic function. Methods A computerized search was performed using Pub-Med, OVID, EMBASE and Cochrane library databases from inception until July, 31 st2022. Full articles reporting data on LV GLS and LVEF in non-dippers and dippers were considered suitable. Results A total of 648 non-dipper and 530 dipper individuals were included in 9 studies. LV GLS was worse in non-dipper than in their dipper counterparts (-18.4±0.30 vs -20.1±0.23%), SMD: 0.73±0.14, CI: 0.46/1.00, p < 0.0001) whereas this was not the case for LVEF (61.4±0.8 and 62.0±0.8%, respectively), SMD: -0.15±0.09, CI: -0.32/0.03, p=1.01). A meta-regression analysis between night-time systolic BP and myocardial GLS showed a significant, relationship between these variables (coefficient 0.085, p < 0.0001). Conclusions Our findings suggest that early changes in LV systolic function not detectable by conventional echocardiography in the non-dipping setting can be unmasked by STE; implementation of STE in current practice may improve the detection of HMOD of adverse prognostic significance in individuals with altered circadian BP rhythm.

Myocardial strain of the left ventricle by speckle tracking echocardiography: From physics to clinical practice

“…The relation between End diastolic volume and LVEF is nonlinear, being the slope steepest for smaller volumes 12 Abbreviations: GCS, global circumferential strain; GLS, global longitudinal strain; LVEF, left ventricular ejection fraction. 123,124 : GLS has shown to be able to unmask systolic dysfunction undetected by conventional LVEF, 125 also in specific settings as masked hypertension 126 and non-dippig pattern 127 ; furthermore, antihypertensive treatment has shown a clear beneficial effect on LV mechanisms, leading to improvements in GLS. 128 Sarcomeric and non-sarcomeric HCMs are typically characterized by heterogeneous echocardiographic patterns of LVH, often with a normal or supernormal EF.…”

“…On the other hand, hypertensive heart disease is characterized by cardiac hypertrophy in response to increased cardiac afterload, and by progressive myocardial fibrosis. STE‐derived GLS is reduced in hypertension, while LV radial and circumferential strains remain well preserved 123,124 : GLS has shown to be able to unmask systolic dysfunction undetected by conventional LVEF, 125 also in specific settings as masked hypertension 126 and non‐dippig pattern 127 ; furthermore, antihypertensive treatment has shown a clear beneficial effect on LV mechanisms, leading to improvements in GLS 128 …”

Challenges in Echocardiography for the Diagnosis and Prognosis of Non-Ischemic Hypertensive Heart Disease

“…Hence, an increase in afterload may lead to a decreased GLS, thereby attenuating the accuracy of research results [98]. A growing number of studies suggests that speckle tracking performs better than LVEF, since it may uncover subtle LV systolic dysfunction in hypertensive patients, before LVEF starts declining [99]. A compensatory modality using myocardial strain with a limited influence of blood pressure on its results is the myocardial work index [100].…”

Commentary on: ‘Cuspidi C., et al. Left ventricular systolic dysfunction in obesity: a meta-analysis of speckle tracking echocardiographic studies’

“…Notably, Cuspidi et al [1] affirm that their data suggest that calculation of GLS should be incorporated into routine work-up aimed to identify obesity-mediated subclinical cardiac damage [1]. Although multiimaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, standard echocardiography remains, at least in my opinion, the most cost-effective technique [7].…”

“…The main aim of the study by Cuspidi et al . [1], published in the present issue of the Journal of Hypertension, was to provide the results of a meta-analysis of studies that evaluated cardiac function in obese patients by speckle tracking echocardiography; the authors’ main conclusion was that calculation of left ventricular (LV) global longitudinal strain (GLS) may identify early/limited/subtle LV systolic dysfunction that the calculation of LV ejection fraction by standard echocardiography was unable to identify [1].…”