scholarly journals Elevated septal wall stress - a driver of left ventricular dysfunction in left bundle branch block?

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
OJ Sletten ◽  
JM Aalen ◽  
EW Remme ◽  
H Izci ◽  
J Duchenne ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): The Norwegian Health Association Background Septal dysfunction is a main feature of left bundle branch block (LBBB), and increasing wall stress is a proposed mechanism of heart failure development in LBBB patients. To try to reveal the pathophysiologic pathway from dyssynchrony to heart failure, we investigated the relationship between septal and left ventricular (LV) lateral wall stress in patients with LBBB. Hypothesis Increased septal wall stress causes septal dysfunction in LBBB. Methods We included 24 LBBB-patients (65 ± 11 years, 11 males) with LV ejection fraction (EF) ranging from 18 to 67%, and 8 healthy controls (58 ± 10 years, 4 males). Wall stress was calculated at peak LV pressure (LVP) according to the law of La Place ([LVP x radius]/[wall thickness]). Wall thickness was measured using M-mode, and regional curvature was measured in mid-ventricular shortaxis from 2D echocardiographic images. We used a previously validated non-invasive method to estimate LVP from brachial blood pressure and adjusted for valvular events. Myocardial scar was ruled out by late gadolinium enhancement cardiac magnetic resonance imaging. Results Wall stress was significantly higher in septum than LV lateral wall at peak LVP (48 ± 12 vs 37 ± 11 kPa, p < 0.01) in LBBB patients, while no difference was seen in the controls (Figure A). In patients, septal wall thickening showed a strong correlation with LVEF (r = 0.77, p < 0.01) (Figure B). Similar correlation was not significant for the LV lateral wall (r = 0.13, NS). Attenuation of septal wall thickening in LBBB-patients correlated well with increasing septal wall stress (r=-0.60, p < 0.01). Wall thickening and stress did not correlate in the LV lateral wall (r=-0.14, NS). Conclusion Increased septal wall stress is associated with reduced systolic thickening in patients with LBBB. Septal wall thickening, in contrast to LV lateral wall thickening, was correlated to global LV function. These findings suggest that septal remodeling which could have normalized septal wall stress, was not achieved and heart failure may develop. Abstract Figure.

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
OJ Sletten ◽  
JM Aalen ◽  
H Izci ◽  
J Duchenne ◽  
EW Remme ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): The Norwegian Health Association Background Left bundle branch block (LBBB) worsen prognosis in heart failure patients. LBBB may also cause heart failure in otherwise healthy individuals. The mechanical changes induced by LBBB are potential determinants of heart failure in these patients, but their relation to left ventricular (LV) systolic function is incompletely understood. Purpose This study investigates the contribution of regional contractile function to heart failure in patients with LBBB. Methods In 76 patients with LBBB and 11 healthy controls, myocardial strain was measured by speckle-tracking echocardiography and myocardial work by pressure-strain analysis. Patients with ischemic heart disease or myocardial scarring were excluded. LBBB patients were stratified by LV ejection fraction (EF) >50% (EFpreserved), 36-50% (EFmid), and ≤35% (EFlow). 62 LBBB patients subsequently underwent cardiac resynchronization therapy (CRT) implantation and was re-examined at 6 months. Results Septal work was significantly and successively reduced from controls, EFpreserved, EFmid, to EFlow (1977 ± 506, 1025 ± 342, 601 ± 494 and -41 ± 303 mmHg·%, respectively, all p < 0.01) (Figure 1). There was a strong correlation (R = 0.84, p < 0.01) between septal work and LVEF. In contrast, work in the LV lateral wall was preserved in both EFpreserved (2367 ± 459 mmHg·%) and EFmid (2252 ± 449 mmHg·%) vs controls (2062 ± 459 mmHg·%, all NS). In the EFlow group, however, LV lateral wall work was reduced (1473 ± 568 mmHg·%, p < 0.01 vs controls). Thus, lateral wall function was not correlated with LVEF in patients with LVEF >35% (NS). At six month CRT septal work was markedly increased (165 ± 485 vs 1288 ± 523 mmHg·%, p < 0.01) and LV lateral wall work reduced (1730 ± 620 vs 1264 ± 490 mmHg·%, p < 0.01). LVEF increased from 32 ± 8 to 47 ± 10 % (p < 0.01). Conclusions Heart failure in LBBB patients is determined by degree of septal dysfunction. LV lateral wall function, on the other hand, is preserved in the early phase of heart failure and was only reduced in patients with severe heart failure. Further clinical studies should investigate if measuring LV lateral wall function can increase precision in patient selection for CRT. Abstract Figure.


2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
K Kupczynska ◽  
KA Nguyen ◽  
E Surkova ◽  
CH Palermo ◽  
F Sambugaro ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Karolina Kupczynska was supported by research grant awarded by the Club 30 of the Polish Cardiac Society Background Left bundle branch block (LBBB) affects left ventricular (LV) mechanics and promotes systolic dysfunction. Purpose To analyse myocardial work (MW) and myocardial work efficiency (MWE) of the septal and LV lateral wall in healthy controls and LBBB patients with various degrees of LV dysfunction using non-invasive method. Methods Our study involved 102 healthy controls (mean age 41.5 ± 15.7 years, 45% male) and 58 LBBB patients without coronary artery disease (mean age 65 ± 13 years, 60% male) divided into 3 groups based on their LVEF: preserved (n= 27), mid-range (n= 16) and reduced (n= 15). Myocardial work parameters were estimated in septal and lateral wall by LV pressure-strain loop obtained by echocardiography. Results There were no differences between septal and lateral MW and MWE in healthy controls (p = NS). We found lower septal MW in comparison to lateral MW (p < 0.0001), but there were no differences in MWE (p = NS) in LBBB patients with preserved LVEF. Patients with LBBB and mid-range or reduced LVEF had lower MW (p < 0.0001 in both subgroups) and lower MWE (p = 0.002 and p = 0.0001, respectively) in septum compared with lateral wall. There was a progressive decrease in septal MW and MWE with the occurring of LBBB and the worsening of LVEF (figure A). Interestingly in healthy controls there was significantly lower lateral MW but higher MWE in comparison to group with LBBB and preserved LVEF. We did not detect differences between LBBB groups with preserved and mid-range LVEF, but patients with reduced LVEF had significant reduction in terms of lateral MW and MWE (figure B). Conclusions Impairment in septal myocardial work escalated according to the appearance of LBBB and LVEF loss. Septal dysfunction was compensated by the effective myocardial work of the lateral wall in LBBB patients with preserved and mid-range LVEF. Mechanical dysfunction of the lateral wall was associated with severely reduced LVEF. Abstract Figure.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
J Duchenne ◽  
S Calle ◽  
A Puvrez ◽  
F Rega ◽  
F Timmermans ◽  
...  

Abstract Introduction Recent cross-sectional studies suggest a relationship between persisting left bundle branch block (LBBB) and the extent of left ventricular (LV) electro-mechanical alterations over time. When patients are referred for cardiac resynchronization therapy (CRT), temporal data during the sub-clinical phase of disease is often missing. A longitudinal study using an animal model would provide a better understanding of the relationship between the onset of LBBB and the electro-mechanical changes. Purpose To investigate the sequential alterations in LV structure and function that develop over time in an animal model of LBBB. Methods Thirteen sheep were subjected to rapid DDD pacing (180 bpm; leads on right atrium and right ventricular free wall) in order to induce a LBBB-like conduction delay. All animals underwent an 8-week pacing protocol, whereas 4 of them were subjected to 16 weeks of pacing in total. Echocardiographic speckle tracking was used to assess circumferential strain of the septal and lateral wall. Septal and lateral wall thickness were measured at end-diastole. Cardiac magnetic resonance imaging was used to determine LV volumes and ejection fraction (LVEF). Examinations took place at baseline (before and after start of pacing), and after 8 and 16 weeks of pacing. All examinations were performed at a physiologic heart rate of 110 bpm. Results At baseline, DDD pacing induced an increase in QRS duration (+85%, p<0.0001) and LBBB-like mechanical dyssynchrony, with mild early-systolic notching and preserved systolic shortening of the septal wall. The lateral wall demonstrated early pre-stretch followed by increasing systolic shortening. No acute changes in LV end-diastolic volume, LVEF or septal or lateral wall thickness were observed (all p>0.05). After 8 weeks of DDD pacing, mechanical dyssynchrony worsened: septal notching increased, followed by reduced systolic shortening. After 16 weeks, the initial septal shortening was followed by profound stretching throughout systole. Lateral wall systolic shortening was reduced compared to baseline. QRS duration increased further by +12% (week 8) and +20% (week 16) (all p<0.001). End-diastolic volumes had increased by +39% (week 8) and +72% (week 16), whereas LVEF had decreased by −48% (week 8) and −56% (week 16) (all p<0.001). Septal wall thickness had reduced by −24% (week 8) and −33% (week 16), while lateral wall thickness had increased by +21% (week 8) and +30% (week 16) (all p<0.05). Conclusion A persisting LBBB-like conduction delay induces sequential changes in LV deformation patterns, and triggers morphological and electrical remodelling. These changes are similar to those observed in patients with LBBB and different degrees of LV dysfunction. Our data suggest a continuum due to the progression of LBBB-induced LV disease. In the clinic, patients with mild dysfunction should be closely monitored in order to treat dyssynchrony as soon as guideline indications are reached. FUNDunding Acknowledgement Type of funding sources: Other. Main funding source(s): This work was supported by a KU Leuven research grant


EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
N Shirokov ◽  
V Kuznetsov ◽  
V Todosiichuk ◽  
A Soldatova ◽  
D Krinochkin

Abstract Funding Acknowledgements Type of funding sources: None. Background Left bundle branch block (LBBB) assessed by electrocardiography (ECG) is used in current clinical guidelines for patient selection to cardiac resynchronisation therapy (CRT). But percentage of non-responders among patients with congestive heart failure is high. Super-response (SR) to CRT was not enough described in clinical guidelines. We hypothesized that mechanical patterns of LBBB and parameters of mechanical dyssynchrony could be used as predictors of SR to CRT. Aim To assess a relationship of LBBB patterns defined by ECG and echocardiography with SR to CRT. Materials and methods 60 patients (mean age 54.5 ± 10.4 years) were examined at baseline and during follow-up: 10.6 ± 3.6 months. Patients were divided into groups: I group (n = 31) with decrease of left ventricular end-systolic volume (ESV) ≥30% (super-responders) and II group (n = 29) - decrease of LV ESV <30% (non-super-responders). Three strain-markers of LBBB assessed by Tissue Doppler Imaging (TDI) and Speckle Tracking Echocardiography (STE) were used: (1) early contraction of basal or midventricular segment in the septal wall and early stretching of basal or midventricular segment in the lateral wall (yellow arrows); (2) the early peak contraction of the septal wall occurred in the first 70% of the systolic ejection phase (blue arrow); (3) the early stretching wall that showed peak contraction after aortic valve closure (red arrows). The classic LBBB pattern was defined if all three strain-markers were present. The heterogeneous LBBB pattern was defined if two from three strain-markers were present. Results At baseline groups did not differ in main clinical characteristics, including QRS width and LBBB assessed by ECG. Mechanical abnormalities were found only in group I: SF (32.3% vs 0.0%; p = 0.001) and apical rocking (19.4% vs 0.0%; p = 0.024), as well as classic LBBB mechanical pattern (20.8% vs 0.0%; p = 0.05). The complex of heterogeneous LBBB mechanical pattern (HR 7.512; 95% CI 1.434 – 39.632; р=0.025), interventricular mechanical delay (HR 1.037; 95% CI 1.005 – 1.071; р=0.017) and longitudinal strain of interventricular septum mid segment (HR 0.726; 95% CI 0.540 – 0.977; р=0.035) had an independent relationship with SR. According to the ROC analysis the sensitivity and specificity of model in the prediction of SR were 77.3% and 91.3% (AUC = 0.862; p < 0.001). Conclusion SR is associated with both LBBB mechanical patterns assessed by STE and TDI. LBBB defined by ECG did not have significant association with SR to CRT. Abstract Figure.


2021 ◽  
Vol 26 (7) ◽  
pp. 4227
Author(s):  
N. E. Shirokov ◽  
V. A. Kuznetsov ◽  
V. V. Todosiychuk ◽  
A. M. Soldatova ◽  
D. V. Krinochkin

Aim. To assess a relationship of left bundle branch block (LBBB) patterns defined by electrocardiography (ECG) and echocardiography with super-response (SR) to cardiac resynchronization therapy (CRT).Material and methods. Sixty patients (mean age, 54,5±10,4 years) were examined at baseline and during follow-up (10,6±3,6 months). Patients were divided into groups: group I (n=31) — decrease of left ventricular end-systolic volume (ESV) ≥30% (super-responders) and II group (n=29) — decrease of LV ESV <30% (non-super-responders). Three strain-markers of LBBB assessed by tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) were used: early contraction of basal or midventricular segment in the septal wall and early stretching of basal or midventricular segment in the lateral wall (marker 1); early peak contraction of the septal wall occurred in the first 70% of the systolic ejection phase (marker 2, septal flash (SF)); early stretching wall that showed peak contraction after aortic valve closure (marker 3). The classical LBBB pattern was defined if all three strain-markers were present. The heterogeneous LBBB pattern was defined if two from three strain-markers were present.Results. At baseline, groups did not differ in main clinical characteristics, including QRS width and LBBB assessed by ECG. Mechanical abnormalities were found only in group I: SF (32,3% vs 0,0%; p=0,001) and apical rocking (19,4% vs 0,0%; p=0,024), as well as classic LBBB mechanical pattern (20,8% vs 0,0%; p=0,05). The complex of heterogeneous LBBB mechanical pattern (odds ratio (OR), 7,512; 95% CI, 1,434-39,632; р=0,025), interventricular mechanical delay (OR, 1,037; 95% CI, 1,005-1,071; р=0,017) and longitudinal strain of interventricular septum mid segment (OR, 0,726; 95% CI, 0,540-0,977; р=0,035) had an independent relationship with SR. According to the ROC analysis, the sensitivity and specificity of model in SR prediction were 77,3% and 91,3% (AUC=0,862; p<0,001).Conclusion. SR is associated with both LBBB mechanical patterns assessed by STE and TDI. LBBB defined by ECG did not have significant association with SR to CRT.


2020 ◽  
Author(s):  
João Ferreira ◽  
Célia Marques Domingues ◽  
Susana Isabel Costa ◽  
Maria Fátima Franco Silva ◽  
Lino Manuel Martins Gonçalves

Abstract Background Implantable cardiac defibrillators (ICD) are a popular and effective option in heart failure with left ventricular systolic dysfunction patients. Although frequently underdiagnosed, inadvertent malposition can lead to endocardial damage and thrombotic events. As ICD implants tend to increase in the following years, the recognition of their complications is critical. Case presentation The authors present a case of a 64-year-old woman with advanced heart failure and ICD malposition. This accidental discovery was denounced by the presence of a right bundle branch block pattern and later confirmed by echocardiography which showed the lead tip in contact with the mid segment of the left ventricular antero-lateral wall. As the patient hospitalisation was complicated with refractory ascites and cardiogenic shock, she underwent cardiac transplantation, with no recurrence of heart failure symptoms. Conclusions An electrocardiogram showing a right bundle branch block pattern during VVI pacing should arise the suspicion of inadvertent placement of a pacing/ICD lead. The many facets of echocardiography should be used for the diagnosis of this complication, as they were paramount in this case, as highlighted.


Sign in / Sign up

Export Citation Format

Share Document