scholarly journals A Comparative Study of Systolic and Diastolic Mechanical Synchrony in Canine, Primate, and Healthy and Failing Human Hearts

2021 ◽  
Vol 8 ◽  
Author(s):  
Tiangang Zhu ◽  
Ming Lei ◽  
Zhilong Wang ◽  
Rongli Zhang ◽  
Yan Zhang ◽  
...  

Aim: Mechanical dyssynchrony (MD) is associated with heart failure (HF) and may be prognostically important in cardiac resynchronization therapy (CRT). Yet, little is known about its patterns in healthy or diseased hearts. We here investigate and compare systolic and diastolic MD in both right (RV) and left ventricles (LV) of canine, primate and healthy and failing human hearts.Methods and Results: RV and LV mechanical function were examined by pulse-wave Doppler in 15 beagle dogs, 59 rhesus monkeys, 100 healthy human subjects and 39 heart failure (HF) patients. This measured RV and LV pre-ejection periods (RVPEP and LVPEP) and diastolic opening times (Q-TVE and Q-MVE). The occurrence of right (RVMDs) and left ventricular systolic mechanical delay (LVMDs) was assessed by comparing RVPEP and LVPEP values. That of right (RVMDd) and left ventricular diastolic mechanical delay (LVMDd) was assessed from the corresponding diastolic opening times (Q-TVE and Q-MVE). These situations were quantified by values of interventricular systolic (IVMDs) and diastolic mechanical delays (IVMDd), represented as positive if the relevant RV mechanical events preceded those in the LV. Healthy hearts in all species examined showed greater LV than RV delay times and therefore positive IVMDs and IVMDd. In contrast a greater proportion of the HF patients showed both markedly increased IVMDs and negative IVMDd, with diastolic mechanical asynchrony negatively correlated with LVEF.Conclusion: The present IVMDs and IVMDd findings have potential clinical implications particularly for personalized setting of parameter values in CRT in individual patients to achieve effective treatment of HF.

2018 ◽  
Vol 5 (2) ◽  
pp. 46-51
Author(s):  
Sanjaya Kumar Shrestha

Introductions: Wide QRS complex with left bundle branch block morphology is one of the three criteria for cardiac resynchronization therapy (CRT) in heart failure (HF) patients who do not improve on medical management. Approximately 30% of patients do not respond to CRT. This study investigates to find out to what extent the wide QRS duration correlates with the intraventricular mechanical dyssynchrony (IVMD) as measured by Tissue Doppler Imaging (TDI) echocardiography. Methods: The HF patients of dilated or ischemic cardiomyopathy with ejection fraction £35% admitted in the medical ward of Patan Hospital, Nepal from March to August 2017 were enrolled in the study. They were divided into two groups, narrow QRS duration of <120ms (Gr1) and wide QRS duration of ³120ms (Gr2). TDI was performed to measure time to peak systolic velocity of the left ventricular walls. The IVMD, defined as 60 ms (millisecond) or greater difference in time to peak velocity between any two points of the left ventricular walls, was compared in both groups. Results: There were 26 patients, 18 in group-1, and eight in Gr2.In Gr1, IVMD was observed 13/18 (72%) patients and in group-2 in 7/8 (87%) patients, (χ2 = 0.70, p = 0.403). There was no significant difference of IVMD between Gr1 and Gr2 (73±36ms vs 97±38ms, t = 1.54, p = 0.136).   Conclusions: Assessment of intraventricular mechanical dyssynchrony (IVMD) by Tissue Doppler Imaging (TDI) is probably superior to QRS duration in heart failure patients.


2015 ◽  
Vol 25 (S2) ◽  
pp. 124-130 ◽  
Author(s):  
Mitchell I. Cohen

AbstractExtrapolating cardiac resynchronization therapy (CRT) to pediatric patients with heart failure has at times been difficult given the heterogeneity of pediatric cardiomyopathies, varying congenital heart disease (CHD) substrates, and the fact that most pediatric heart failure patients have right bundle branch block (RBBB) as opposed to LBBB. Yet, despite these limitations a number of multi-center retrospective studies in North America and Europe have identified some data to suggest that certain sub-populations tend to respond positively to CRT. In order to address some of the heterogeneity it is helpful to subdivide pediatric and young adult patients with CHD into four potential groups: (1) CRT for chronic RV pacing, (2) dilated cardiomyopathies, (3) pulmonary right ventricles, and (4) systemic right ventricles. The chronic RV paced group, especially long-standing RV apical pacing, with ventricular dyssynchrony has consistently shown to be the group that best responds to a proactive resynchronization course. CRT therapy in pulmonary right ventricles such as post-op tetralogy of Fallot have shown some promise and may be considered especially if there is evidence of concomitant left ventricular dysfunction with an electrical dyssynchrony. Patients with systemic right ventricles such as post-atrial baffle surgery or congenitally corrected transposition reportedly do well with CRT in the presence of both inter-ventricular and intra-ventricular dyssynchrony. There is little doubt that moving forward to best way to identify which pediatric patients with heart failure will respond to CRT, will require a collaborative effort between the electrophysiologist and the echocardiographer to identify appropriate candidates with electrical and mechanical dyssynchrony.


2018 ◽  
pp. 49-59 ◽  
Author(s):  
A. M. Soldatova ◽  
V. A. Kuznetsov ◽  
D. V. Krinochkin ◽  
T. N. Enina ◽  
N. E. Shirokov

The aim.To evaluate clinical, morphological, functional features and mortality in patients with congestive heart failure (CHF) and super-response to cardiac resynchronization therapy (CRT), to assess presence and severity of mechanical dyssynchrony in patients with super-response and to find potential predictors of super-response to CRT.Methods.106 CRT patients (mean age 54.7 ± 9.9 years; 83% men) with CHF II–IV NYHA functional class were enrolled for the study. At baseline and each 6 months after implantation clinical, electrocardiographic and echocardiographic parameters, NT-proBNP level were evaluated. According to the best decrease of left ventricular endsystolic volume (LVESV) (mean follow-up period 34.9 ± 16.1 months) patients were classified as super-responders (SR) (n = 45; reduction in LVESV ≥30%) and non-SR (n = 61; reduction in LVESV <30%).Results.At baseline groups were matched for main clinical characteristics. The proportion of patients with atrial fibrillation, width of the QRS complex, and the presence of left bundle-branch block were comparable between groups. Parameters of mechanical dyssynchrony were higher in SR: left ventricular pre-ejection period (LVPEP) (153.0 ± 35.9 ms vs 126.6 ± 35.1 ms; р = 0.005), interventricular mechanical delay (55.9 ± 30.8 ms vs 40.4 ± 29.9 ms; р = 0.049), systolic dyssynchrony index (9.6 ± 2.6% vs 7.2 ± 0.7%; р = 0.048). NT-proBNP level was lower in SR. SR demonstrated better dynamics of LVESV, LVEF. At baseline and in dynamics level of NT-proBNP was lower in SR. In both groups NT-proBNP decreased significantly, but reduction of NT-proBNP was more evident in SR. The survival rates were 100%in SR and 83.6% in non-SR (log rank test p = 0.002).According to multiple logistic regression analysis LVPEP (HR 1.025; 95% CI 1.006–1.044; p = 0.010) and baseline NT-proBNP level (HR 0.624; 95% CI 0.426–0.913; p = 0.015) were independent predictors for CRT super-response with sensitivity 71.9% and specificity 78.6%.Conclusion.In patients with CHF greater mechanical dyssynchrony and lower level of NT-proBNP are associated with CRT super-response. SR demonstrate better survival and better dynamics of functional parameters in long-term period. LVPEP and NT-proBNP level can be used as independent predictors of CRT super-response.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
D Yagishita ◽  
Y Yagishita ◽  
S Kataoka ◽  
K Yazaki ◽  
M Kanai ◽  
...  

Abstract Introduction In our previous report, the time interval from left ventricular (LV) pacing to the earliest onset of QRS (S-QRS interval) has been found to be an independent predictor of mechanical response to cardiac resynchronization therapy (CRT). The S-QRS interval may indicate the conduction disturbance relevant to the localized tissue property such as scar or fibrotic lesion. Therefore, S-QRS interval longer than 37ms was associated with poor response to CRT, and proposed as suboptimal LV lead position. Then, we hypothesized that the longer S-QRS interval at the LV pacing site could be related to long term mortality and heart failure events in patients with CRT. Methods This retrospective study included 82 consecutive heart failure patients with sinus rhythm, reduced LV ejection fraction (≤35%), and a wide QRS complex (≥120ms), who undergone CRT implantation between 2012 January and 2017 December. Patients were divided into Short S-QRS group (&lt;37ms, SS-QRS) and Long S-QRS group (≥37ms, LS-QRS) according to the previously reported optimal cut off value. A responder was defined as one with ≥15% reduction in LV end-systolic volume assessed by echocardiography at 6 months after CRT. The primary endpoint was total mortality, which included LV assist device implantation or heart transplantation. The secondary endpoints included the composite endpoint of total mortality or heart failure hospitalization. Results The study patients were divided into SS-QRS (N=43, age 65.9±13.2 years, 77% male) and LS-QRS (N=39, age 63.0±13.4, 85% male). In the electrocardiographic measurements, there were no significant differences in baseline QRS duration (162.4±30.3ms in SS-QRS vs. 154.5±31.6ms in LS-QRS, P=0.19) and LV local activation time assessed as Q-LV interval (118.3±34.3ms in SS-QRS vs. 115.3±32.0ms in LS-QRS, P=0.71). S-QRS interval was 25.9±5.3ms in SS-QRS and 51.5±13.7ms in LS-QRS (P&lt;0.01), and the responder rate was significantly higher in SS-QRS compared with LS-QRS (79% vs. 29%, P&lt;0.01). During mean follow up of 47.7±22.4 months, 24 patients (29%) reached to the primary endpoint, while the secondary endpoints were observed in 47 patients (57%). LS-QRS patients had significantly worse event-free survival for both primary and secondary endpoints (Figure). After the multivariate Cox regression analysis, LS-QRS (≥37ms) was an independent predictor of total mortality (HR=2.6, 95% CI: 1.11 to 6.12, P=0.03) and the secondary composite events (HR=2.4, 95% CI: 1.31 to 4.33, P&lt;0.01). Conclusion The S-QRS interval longer than 37ms, which may reflect the conduction disturbance relevant to the scar or fibrotic lesion at the LV pacing site, was a significant predictor of the total mortality and heart failure hospitalization. These findings have implications for the optimal LV lead placement in patients with CRT device. Clinical outcomes according to S-QRS Funding Acknowledgement Type of funding source: None


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Duchenne ◽  
M Cvijic ◽  
J.M Aalen ◽  
C.K Larsen ◽  
E Galli ◽  
...  

Abstract Background The presence of mechanical dyssynchrony – such as apical rocking (ApRock) and septal flash (SF) – on echocardiography is associated with favourable outcome after cardiac resynchronization therapy (CRT). Myocardial scar on the other hand, has a considerable negative impact on CRT response. There is growing evidence that a visual echocardiographic assessment of mechanical dyssynchrony by ApRock, SF and scar predicts CRT response. Little is known however if this works equally well in patients with intermediate QRS duration (120–150ms), where guideline recommendation for CRT is weaker. Methods A total of 400 unselected patients referred for CRT, who fulfil the contemporary guidelines, were enrolled in this multicentre study. Echocardiographic images were visually assessed before CRT implantation, focussing on the presence of ApRock, SF and location and extent of scar segments in the left ventricle (LV), resulting in a CRT response prediction (i.e. Reader Interpretation). Readers were blinded to all patient information other than ischaemic aetiology of heart failure. CRT response was defined as ≥15% reduction in LV end-systolic volume on echocardiography, on average 15 months after device implantation. Results Overall, 321 (80%) patients had a left bundle branch block (LBBB), with an average QRS duration of 166±25ms. Ischemic aetiology of heart failure was found in 131 (33%) patients. Before CRT, ApRock and SF were present in 254 (64%) and 244 (61%) patients, respectively. ApRock and SF alone predicted CRT response with an area under the curve (AUC) of 0.79 (95% CI: 0.74–0.84) and 0.78 (95% CI: 0.73–0.83) (Figure A), while the echocardiographic Reader Interpretation had an AUC of 0.85 (95% CI: 0.81–0.89), with a sensitivity of 89% and a specificity of 82% for the prediction of CRT response (Figure B) (p&lt;0.0001 vs. ApRock and SF alone). A total of 92 patients had a QRS duration of 120–150ms, and 48 of them responded to CRT. In these patients, the AUC of Reader Interpretation was comparable to that of the entire study cohort [0.83 (95% CI: 0.75–0.92)], as was sensitivity and specificity (90% and 79%, respectively, p=0.717 vs. the AUC of the entire cohort) (Figure C). Conclusions A visual assessment of LV function, by means of mechanical dyssynchrony and scar, has an excellent predictive value for CRT response, and requires only apical echocardiographic images. Responders were identified equally well in the challenging subgroup of patients with a QRS duration of 120–150 ms. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): KU Leuven


2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
E Galli ◽  
V Le Rolle ◽  
OA Smiseth ◽  
J Duchenne ◽  
JM Aalen ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Background Despite having all a systolic heart failure and broad QRS, patients proposed for cardiac resynchronization therapy (CRT) are highly heterogeneous and it remains extremely complicated to predict the impact of the device on left ventricular (LV) function and outcomes. Objectives We sought to evaluate the relative impact of clinical, electrocardiographic, and echocardiographic data on the left ventricular (LV) remodeling and prognosis of CRT-candidates by the application of machine learning (ML) approaches. Methods 193 patients with systolic heart failure undergoing CRT according to current recommendations were prospectively included in this multicentre study. We used a combination of the Boruta algorithm and random forest methods to identify features predicting both CRT volumetric response and prognosis (Figure 1). The model performance was tested by the area under the receiver operating curve (AUC). We also applied the K-medoid method to identify clusters of phenotypically-similar patients. Results From 28 clinical, electrocardiographic, and echocardiographic-derived variables, 16 features were predictive of CRT-response; 11 features were predictive of prognosis. Among the predictors of CRT-response, 7 variables (44%) pertained to right ventricular (RV) size or function. Tricuspid annular plane systolic excursion was the main feature associated with prognosis. The selected features were associated with a very good prediction of both CRT response (AUC 0.81, 95% CI: 0.74-0.87) and outcomes (AUC 0.84, 95% CI: 0.75-0.93) (Figure 1, Supervised Machine Learning Panel). An unsupervised ML approach allowed the identifications of two phenogroups of patients who differed significantly in clinical and parameters, biventricular size and RV function. The two phenogroups had significant different prognosis (HR 4.70, 95% CI: 2.1-10.0, p &lt; 0.0001; log –rank p &lt; 0.0001; Figure 1, Unsupervised Machine Learning Panel). Conclusions Machine learning can reliably identify clinical and echocardiographic features associated with CRT-response and prognosis. The evaluation of both RV-size and function parameters has pivotal importance for the risk stratification of CRT-candidates and should be systematically assessed in patients undergoing CRT. Abstract Figure 1


2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
V Saushkin ◽  
YV Varlamova ◽  
AI Mishkina ◽  
DI Lebedev ◽  
SV Popov ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Aim/Introduction: Assessment of mechanical dyssynchrony by myocardial perfusion gated-SPECT in patients with non-ischemic cardiomyopathy for predict response to cardiac resynchronization therapy (CRT). Materials and Methods  We examined 32 patients with non-ischemic cardiomyopathy before and six months after CRT.  Left ventricular mechanical dyssynchrony and contractility were assessed for all patients by myocardial perfusion gated-SPECT. The phase standard deviation (PSD), histogram bandwidth (HBW), phase histogram skewness (S) and phase histogram kurtosis (K) were used as an indicator of mechanical dyssynchrony for the both ventricles.  Results  Mechanical dyssynchrony of both ventricles before CRT was increased in all patients. Median value PSD 53°(41-61°), HBW 176°(136-202°), S 1,62(1,21-1,89), K 2,81(1,21-3,49). Six months after CRT 22(68%) respondents were identified. We divided the patients into two groups (responders and non-responders) and compared phase parameters. It was found that the PSD (44°(35-54°)) and HBW (158°(118-179°) in the responders were significantly lower than in the non-responders (PSD (68°(58-72°); HBW (205°(199-249°)). The value of phase histogram skewness and kurtosis in responders were significantly higher (Responders: S 1,77(1,62-2,02); K 3,03(2,60-3,58). Non-responders: S 1,21(0,93-1,31); K 1,21(0,19-1,46)).  We found that all four indicators of mechanical dyssynchrony can predict CRT response according to the results of univariate logistic regression analysis. Moreover, It was found that only phase histogram kurtosis (OR = 1.196, 95% CI 1.04-1.37) is an independent predictor of CRT response according to multivariate logistic regression. Conclusion  Radionuclide assessment of mechanical dyssynchrony may be the optimal diagnostic method for selecting patients with non-ischemic cardiomyopathy on CRT.


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