QRS duration in left bundle branch block does not affect left ventricular twisting in chronic systolic heart failure. (31st July 2014)

• Record Type: Journal Article
• Authors: Attanà, Paola; Paoletti Perini, Alessandro; Votta, Carmine Domenico; Cappelli, Francesco; Pieragnoli, Paolo; Ricciardi, Giuseppe; Nesti, Martina; Giomi, Andrea; Sacchi, Stefania; Chiostri, Marco; Padeletti, Luigi
• Is Part Of: Clinical physiology and functional imaging. Volume 35:Number 6(2015:Nov.)
• Page Start: 436
• Page End: 442
• Publication Date: 2014-07-31
• Subjects: Physiology, Pathological -- Periodicals; Diagnostic imaging -- Periodicals; 612
• DOI: 10.1111/cpf.12181
• Languages: English
• ISSNs: 1475-0961

Abstract

<abstract abstract-type="main" id="cpf12181-abs-0001"> <title>Summary</title> <sec id="cpf12181-sec-0001" sec-type="section"> <title>Purpose</title> <p>Left ventricular (LV) torsion is an important parameter of LV performance and can be influenced by several factors. Aim of this investigation was to evaluate whether QRS prolongation in left bundle branch block (LBBB) may influence global LV twist and twisting/untwisting rate in chronic systolic heart failure (HF) patients.</p> </sec> <sec id="cpf12181-sec-0002" sec-type="section"> <title>Methods</title> <p>We prospectively evaluated 30 healthy subjects (control group) and 100 chronic HF patients with severely impaired LV systolic function (ejection fraction ≤35%). Patients were divided into three groups according to QRS duration: A: QRS < 120 ms (<italic>n</italic> 49), B: 120 ≤ QRS ≤ 150 ms (<italic>n</italic> 28) and C: QRS > 150 ms (<italic>n</italic> 23). Patients in groups B and C presented LBBB. All subjects underwent standard trans‐thoracic echocardiography and two‐dimensional speckle‐tracking echocardiography evaluation. Categorical variables were compared by the chi‐square or the Fisher's exact test. Continuous variables were compared using the ANOVA test. Correlations between variables were analysed with linear regression.</p> </sec> <sec id="cpf12181-sec-0003" sec-type="section"> <title>Results</title> <p>Control subjects presented higher torsion parameters, when compared with patients in any HF group. Among the three HF groups, no differences were detected in global twist (4·79 ± 3·54, 3·8 ± 3·0 and 4·15 ± 3·14 degrees, respectively), twist rate max (44·81 ± 25·03, 37·94 ± 19·09 and 37·61 ± 24·49 degrees s<sup>−1</sup>, respectively) and untwist rate max (−36·31 ± 30·89, −27·68 ± 34·67 and −39·62 ± 26·27 degrees s<sup>−1</sup>, respectively) (<italic>P</italic>>0·05 for all). At linear regression analysis, there was no relation between QRS duration and any torsion parameter (<italic>P</italic>>0·05 for all).</p> </sec> <sec id="cpf12181-sec-0004" sec-type="section"> <title>Conclusions</title> <p>In patients with chronic severe systolic heart failure, QRS duration and LBBB morphology do not affect LV twisting and untwisting.</p> </sec> </abstract>