scholarly journals Improved Left Atrial Function in CRT Responders: A Systematic Review and Meta-Analysis

2020 ◽  
Vol 9 (2) ◽  
pp. 298 ◽  
Author(s):  
Ibadete Bytyçi ◽  
Gani Bajraktari ◽  
Per Lindqvist ◽  
Michael Y. Henein
Keyword(s):  
Left Atrial ◽  
Weighted Mean Difference ◽  
Meta Analysis ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Weighted Mean ◽  
Systolic Volume ◽  
End Systolic Volume ◽  
The Relationship

Cardiac resynchronization therapy (CRT) is associated with reverse left atrial (LA) remodeling. The aim of this meta-analysis was to assess the relationship between clinical response to CRT and LA function changes. We conducted a systematic search of all electronic databases up to September 2019 which identified 488 patients from seven studies. At (mean) 6 months follow-up, LA systolic strain and emptying fraction (EF) were increased in CRT responders, with a −5.70% weighted mean difference (WMD) [95% confidence interval (CI) −8.37 to −3.04, p < 0.001 and a WMD of −8.98% [CI −15.1 to −2.84, p = 0.004], compared to non-responders. The increase in LA strain was associated with a fall in left ventricle (LV) end-systolic volume (LVESV) r = −0.56 (CI −0.68 to −0.40, p < 0.001) and an increase in the LV ejection fraction (LVEF) r = 0.58 (CI 0.42 to 0.69, p < 0.001). The increase in LA EF correlated with the fall in LVESV r = −0.51 (CI −0.63 to −0.36, p < 0.001) and the increase in the LVEF r = 0.48 (CI 0.33 to 0.61, p = 0.002). The increase in LA strain correlated with the increase in the LA EF, r = 0.57 (CI 0.43 to 0.70, p < 0.001). Thus, the improvement of LA function in CRT responders reflects LA reverse remodeling and is related to its ventricular counterpart.

scholarly journals Improvement of LV Reverse Remodeling Using Dynamic Programming of Fusion-Optimized Atrioventricular Intervals in Cardiac Resynchronization Therapy

2021 ◽  
Vol 8 ◽  
Author(s):  
Zhongkai Wang ◽  
Pan Li ◽  
Bili Zhang ◽  
Jingjuan Huang ◽  
Shaoping Chen ◽  
...  
Keyword(s):  
Cardiac Resynchronization Therapy ◽  
Nyha Class ◽  
Left Ventricular ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Resynchronization Therapy ◽  
Systolic Volume ◽  
End Systolic Volume ◽  
The Impact

Background: The patient-tailored SyncAV algorithm shortens the QRS duration (QRSd) beyond what conventional biventricular (BiV) pacing can. However, evidence of the ability of SyncAV to improve the cardiac resynchronization therapy (CRT) response is lacking. The aim of this study was to evaluate the impact of CRT enhanced by SyncAV on echocardiographic and clinical responses.Methods and Results: Consecutive heart failure (HF) patients from three centers treated with a quadripolar CRT system (Abbott) were enrolled. The total of 122 patients were divided into BiV+SyncAV (n = 68) and BiV groups (n = 54) according to whether they underwent CRT with or without SyncAV. Electrocardiographic, echocardiographic, and clinical data were assessed at baseline and during follow-up. Echocardiographic response to CRT was defined as a ≥15% decrease in left ventricular end-systolic volume (LVESV), and clinical response was defined as a NYHA class reduction of ≥1. At the 6-month follow-up, the baseline QRSd and LVESV decreased more significantly in the BiV+SyncAV than in the BiV group (QRSd −36.25 ± 16.33 vs. −22.72 ± 18.75 ms, P &lt; 0.001; LVESV −54.19 ± 38.87 vs. −25.37 ± 36.48 ml, P &lt; 0.001). Compared to the BiV group, more patients in the BiV+SyncAV group were classified as echocardiographic (82.35 vs. 64.81%; P = 0.036) and clinical responders (83.82 vs. 66.67%; P = 0.033). During follow-up, no deaths due to HF deterioration or severe procedure related complications occurred.Conclusion: Compared to BiV pacing, BiV combined with SyncAV leads to a more significant reduction in QRSd and improves LV remodeling and long-term outcomes in HF patients treated with CRT.

Abstract 4244: Longitudinal Cardiac Rotation Affects Systolic Myocardial Velocities and Velocity-Defined Measures Of Ventricular Dyssynchrony

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Zoran Popovic ◽  
Karen Phillips ◽  
Pascal Lim ◽  
John E Meulet ◽  
Conor D Barrett ◽  
...  
Keyword(s):  
Peak Systolic Velocity ◽  
Peak Amplitude ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Lateral Velocity ◽  
Systolic Volume ◽  
Time To Peak ◽  
Chamber View ◽  
Intraventricular Dyssynchrony ◽  
End Systolic Volume

Background : Left ventricle (LV) of cardiac resynchronization therapy (CRT) candidates often displays rotational motion in the horizontal plane, a phenomenon we named longitudinal rotation (LR). We assessed if magnitude and direction of LR affects myocardial velocity-based measures of LV dyssynchrony. Methods : In 100 CRT patients (age 64±13 yrs, 76 men) LR was assessed in the apical 4-chamber view by speckle-tracking while myocardial systolic velocities of basal septum and lateral LV wall were measured from 2-dimensional color tissue Doppler data. Patients were classified into quartiles based on their LR values. Intraventricular dyssynchrony was calculated as the absolute, while septo-lateral delay was calculated as the true difference between the time to peak systolic velocity of the septum and lateral wall. Results : LR in all quartiles except Quartile 4 had a clockwise (negative) direction when viewed in apical 4-chamber view. As quartiles increased, patients were more frequently ischemic, systolic septal velocity and septo-lateral delay decreased, while intraventricular dyssynchrony showed a U shaped relationship (Table ). While difference in peak amplitude of basal septal and lateral systolic velocities and LR correlated with end-systolic volume (ESV) decrease at follow-up in non-ischemic patients (r = 0.44 and r = 0.49, p < 0.01 for both), neither intraventrivcular dyssynchrony nor septal-lateral delay correlated with ESV decrease in either etiology. Conclusions : LR affects amplitudes and timing of myocardial velocities. While difference in peak amplitude of basal septal and lateral systolic velocities and LR predict LV reverse remodeling, time-based velocity measures do not. ICM:/DCM: ischemic/dilated cardiomyopathy; T(sep/lat): time to peak (septal/lateral) systolic velocity; S(sep/lat): peak systolic (septal/lateral) velocity; S-L delay: septo-lateral delay; Dys: intraventricular dyssynchrony; ΔESV: end-systolic volume decrease

Abstract 15358: Cardiac Remodeling in Adults Following Percutaneous Patent Ductus Arteriosus Closure: A Meta-analysis

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Sarah Blissett ◽  
Harsh Agrawal ◽  
Ahmed Kheiwa ◽  
Hope Caughron ◽  
Ian Harris ◽  
...  
Keyword(s):  
Patent Ductus Arteriosus ◽  
Cardiac Remodeling ◽  
Meta Analysis ◽  
Ductus Arteriosus ◽  
Left Ventricular ◽  
Reverse Remodeling ◽  
Weighted Mean ◽  
Post Procedure ◽  
Patent Ductus

Introduction: Patent ductus arteriosus (PDA) is often recognized and treated with percutaneous closure in adults. However, the impact on cardiac reverse remodeling following PDA closure in adults is not clear. We performed a meta-analysis to characterize the extent of cardiac remodeling following percutaneous PDA closure in adults. Methods: MEDLINE and EMBASE were systematically searched for original studies that reported echocardiographic variables at baseline, immediately post-procedure (within 24 hours), and at follow-up (>1 month) in adults undergoing percutaneous PDA closure. Additionally, we included echocardiographic data from a cohort of patients >18 years of age that underwent percutaneous PDA closure between 01/2015 and 12/2019 at our centre. For parameters with sufficient data for pooling, weighted averages were calculated, and pooled differences were presented as weighted mean differences. Heterogeneity was assessed using the I 2 statistic. Results: After screening 278 abstracts, 5 studies were identified. When combined with our own cohort of 13 patients, our meta-analysis encompassed 244 patients. The weighted mean age of all patients was 33 years with all studies predominantly comprised of female patients and the median follow-up was 12 months (ranging from 1 month- 5 years across the studies). When compared to baseline, left ventricular ejection fraction (LVEF) decreased significantly immediately post-procedure and all parameters significantly decreased at follow-up (Table 1). Conclusions: As demonstrated by the decreases in the left ventricular and left atrial sizes, reverse remodeling was observed in adults who underwent percutaneous PDA closure. The significantly lower LVEF immediately post-procedure could reflect withdrawal of chronic volume overload or increased afterload. The clinical significance of the statistically significant lower LVEF on follow-up testing is unclear and requires further evaluation.

scholarly journals Atrial fibrillation recurrence after transcatheter ablation worsens left atrial strain

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Annunziata ◽  
F Notaristefano ◽  
L Spighi ◽  
S Piraccini ◽  
G Giuffre' ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Left Atrial ◽  
Left Atrial Strain ◽  
Systolic Volume ◽  
End Systolic Volume ◽  
Atrial Strain ◽  
Af Recurrence

Abstract Introduction Left atrial strain (LAs) shows correlation with atrial fibrosis and is a predictor of atrial fibrillation (AF) recurrence after transcatheter ablation. Little is known about LAs evolution after ablation. Purpose We sought to evaluate the atrial function with echocardiographic strain before and 6 months after AF ablation. Methods 65 consecutive patients undergoing radiofrequency or cryoballoon ablation for atrial fibrillation at our centre were enrolled. They underwent a transthoracic echocardiography before the procedure and at 6 months follow-up. 5 patients were excluded because of low quality images. Global left atrial strain during the reservoir phase (LASr) was calculated as a mean of the values obtained in 4 and 2 chamber apical view; the ventricular end-diastole was set as reference to allow the calculation both in patients in AF and sinus rhythm during the echocardiography. Recurrence was defined as any atrial arrhythmia episode lasting more than 30 seconds recorded on an EKG strip after the 3 months blanking period; all patients underwent a 24 hours EKG Holter after the blanking period to detect asymptomatic recurrence. Quality of life was assessed before the procedure and at follow-up with the EQ-5D-3L model. Results At 6 months 14 patients (13%) had AF recurrence. Patients with recurrence (AF-R) had similar baseline characteristics compared to those without recurrence (AF-NR) but the former had a longer history of AF (39±53 vs 85±94 months, p=0,018). LASr, LA volume and left ventricle ejection fraction (EF) were similar at baseline between groups. At follow-up LASr was significantly impaired in the AF-R group compared to AF-NR (14±6% vs 26±10% respectively, p&lt;0,0001) whereas LA volume, LV end systolic volume and EF remained similar. Compared to baseline LASr worsened in patients experiencing AF recurrence (22±11% vs 14±6%, p=0.016) and this finding was consistent also in patients in sinus rhythm during both examinations (29±8 vs 17±7, p=0,005). Compared to baseline LASr (22±10% vs 26±10%, p=0.024), LV end-systolic volume (29±15 ml vs 22±6 ml, p=0,006) and EF (51±9% vs 58±18%, p=0,038) improved in the AF-NR group but the effect was driven mainly by patients restoring sinus rhythm. Both groups showed a significant improvement of the quality of life (55±23 vs 85±13, p&lt;0,0001 AF-NR; 63±17 vs 80±12, p=0,012 AF-R). Conclusions Atrial fibrillation recurrence after transcatheter ablation is associated with significant left atrial strain worsening which indicates disease progression and may predispose to further long-term recurrences whereas a successful ablation has a protective effect on atrial function. Funding Acknowledgement Type of funding source: None

P578Multipoint pacing in cardiac resynchronization therapy - how to improve remodeling criteria and its impact in quality of life

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
A Nunes Ferreira ◽  
P S Antonio ◽  
I Aguiar-Ricardo ◽  
T Rodrigues ◽  
N Cunha ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Response Rate ◽  
Reverse Remodeling ◽  
Resynchronization Therapy ◽  
Rate Reduction ◽  
Systolic Volume ◽  
End Systolic Volume ◽  
The Impact

Abstract Background Despite the reduction in mortality and hospitalization rates, resynchronization therapy still has 30-40% of non-responders. Several studies are ongoing to evaluate if novel programming techniques such as multipoint pacing (MPP) increase the conversion rate of non-responder to responder to CRT. However, there is still lack of information about conversion to super-responders and the impact in quality of life of MPP. Purpose To evaluate the impact of MPP in conversion to super-responders and its impact in the quality of life of patients. Methods Randomized clinical trial of non-AF patients with indication for CRT and who implanted the Quartet™ quadripolar left ventricle (LV) lead. After implant, CRTs were programmed on biventricular pacing according to the latest activated area for 6 months. After a 6-month follow-up, patients were randomized in a 1:1 fashion to MPP ON or MPP OFF. MPP was programmed with the two widest spaced LV electrodes and with a LV1-LV2 to LV2-RV delay of 5ms. Patients were followed-up for 12 months with a 6-month evaluation of NTproBNP, echocardiographic remodeling criteria (LV end systolic volume (ESV) and LV ejection fraction), and quality of life (QoL) evaluated by EQ-5D, Minnesota Living with Heart Failure (MLWHF) questionnaire and 6-minute walk test (6MWT). Results  76 patients were included in this trial, 62 with a completed 12-month follow-up (average age 67.2 ± 10.2 years old, 32.3% female gender, dilated cardiomyopathy in 77.4%). Among these patients, 24 were randomized to MPP ON, 28 to MPP OFF. Six patients died and 4 were lost to follow-up. Baseline clinical and echocardiographic characteristics were similar between groups (p = NS). At 6 months, the overall response rate (reduction in ESV≥15%) was 75%. At twelve months, patients randomized to MPP ON had a super-response rate (reduction in ESV≥30%) higher than patients with MPP OFF (75% vs 39.3%, p = 0.01). Between 6-12 months, patients assigned to MPP ON had a higher reduction in ESV (93.4 ± 52.3mL to 82.1 ± 40.5mL, p = 0.04) and an improvement in LVEF (38.3 ± 9.8% to 45.1 ± 11.1%, p &lt; 0.01) compared to patients with MPP OFF (92.2 ± 47.3mL to 95.4 ± 47.5mL, p = NS; 37.1 ± 12.0% to 40.2 ± 9.2%, p = NS). Additionally, QoL of patients with MPP ON improved during follow up (EQ-5D 78.3% to 86.3%, p &lt; 0.01; MLWHF 12.1 to 6.6, p = 0.03, 6MWT 316m to 239m, p = NS; NTproBNP 1608 ± 2450pg/mL to 775 ± 914pg/mL, p = NS) and was unchanged in MPP OFF patients (76.6% to 74.2%; MLWHF 12.7 to 12.7; 6MWT 338m to 299m, NTproBNP 1112 ± 1442pg/mL to 1383 ± 2118pg/mL, for all p = NS). Conclusion In our population, patients with CRT programmed with MPP ON, when compared to MPP OFF, had an improvement in the super-response rate and in quality of life. These results may be consequence from a more favorable reverse remodeling due to MPP, with a higher reduction in the LV end systolic volume. Abstract Figure.

scholarly journals Comparative efficacy of image-guided techniques in cardiac resynchronization therapy: a meta-analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xiao Hu ◽  
Hai Xu ◽  
Shameer Raaj Avishkar Hassea ◽  
Zhiyong Qian ◽  
Yao Wang ◽  
...  
Keyword(s):  
Heart Failure ◽  
Weighted Mean Difference ◽  
Meta Analysis ◽  
Left Ventricular ◽  
Cardiac Resynchronization ◽  
Control Group ◽  
Weighted Mean ◽  
Image Guided ◽  
Lead Placement ◽  
Crt Response

Abstract Background Several studies have illustrated the use of echocardiography, magnetic resonance imaging, and nuclear imaging to optimize left ventricular (LV) lead placement to enhance the response of cardiac resynchronization therapy (CRT) in heart failure patients. We aimed to conduct a meta-analysis to determine the incremental efficacy of image-guided CRT over standard CRT. Methods We searched PubMed, Cochrane library, and EMBASE to identify relevant studies. The outcome measures of cardiac function and clinical outcomes were CRT response, concordance of the LV lead to the latest sites of contraction (concordance of LV), heart failure (HF) hospitalization, mortality rates, changes of left ventricular ejection fraction (LVEF), and left ventricular end-systolic volume (LVESV). Results The study population comprised 1075 patients from eight studies. 544 patients underwent image-guided CRT implantation and 531 underwent routine implantation without imaging guidance. The image-guided group had a significantly higher CRT response and more on-target LV lead placement than the control group (RR, 1.33 [95% CI, 1.21 to 1.47]; p < 0.01 and RR, 1.39 [95% CI, 1.01 to 1.92]; p < 0.05, respectively). The reduction of LVESV in the image-guided group was significantly greater than that in the control group (weighted mean difference, − 12.46 [95% CI, − 18.89 to − 6.03]; p < 0.01). The improvement in LVEF was significantly higher in the image-guided group (weighted mean difference, 3.25 [95% CI, 1.80 to 4.70]; p < 0.01). Pooled data demonstrated no significant difference in HF hospitalization and mortality rates between two groups (RR, 0.89 [95% CI, 0.16 to 5.08]; p = 0.90, RR, 0.69 [95% CI, 0.37 to 1.29]; p = 0.24, respectively). Conclusions This meta-analysis indicates that image-guided CRT is correlated with improved CRT volumetric response and cardiac function in heart failure patients but not with lower hospitalization or mortality rate.

scholarly journals KL-6 as an Immunological Biomarker Predicts the Severity, Progression, Acute Exacerbation, and Poor Outcomes of Interstitial Lung Disease: A Systematic Review and Meta-Analysis

2021 ◽  
Vol 12 ◽  
Author(s):  
Tao Zhang ◽  
Ping Shen ◽  
Chunyan Duan ◽  
Lingyun Gao
Keyword(s):  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Acute Exacerbation ◽  
Adverse Outcome ◽  
Weighted Mean Difference ◽  
Meta Analysis ◽  
Effect Sizes ◽  
Weighted Mean ◽  
Poor Outcomes ◽  
The Relationship

ObjectInterstitial lung disease (ILD) is a specific form of chronic fibrosing interstitial pneumonia with various etiology. The severity and progression of ILD usually predict the poor outcomes of ILD. Otherwise, Krebs von den Lungen-6 (KL-6) is a potential immunological biomarker reflecting the severity and progression of ILD. This meta-analysis is to clarify the predictive value of elevated KL-6 levels in ILD.MethodEBSCO, PubMed, and Cochrane were systematically searched for articles exploring the prognosis of ILD published between January 1980 and April 2021. The Weighted Mean Difference (WMD) and 95% Confidence Interval (CI) were computed as the effect sizes for comparisons between groups. For the relationship between adverse outcome and elevated KL-6 concentration, Hazard Ratio (HR), and its 95%CI were used to estimate the risk factor of ILD.ResultOur result showed that ILD patients in severe and progressive groups had higher KL-6 levels, and the KL-6 level of patients in the severe ILD was 703.41 (U/ml) than in mild ILD. The KL-6 level in progressive ILD group was 325.98 (U/ml) higher than that in the non-progressive ILD group. Secondly, the KL-6 level of patients in acute exacerbation (AE) of ILD was 545.44 (U/ml) higher than stable ILD. Lastly, the higher KL-6 level in ILD patients predicted poor outcomes. The KL-6 level in death of ILD was 383.53 (U/ml) higher than in survivors of ILD. The pooled HR (95%CI) about elevated KL-6 level predicting the mortality of ILD was 2.05 (1.50–2.78), and the HR (95%CI) for progression of ILD was 1.98 (1.07–3.67).ConclusionThe elevated KL-6 level indicated more severe, more progressive, and predicted the higher mortality and poor outcomes of ILD.

scholarly journals Strain-based staging classification of left bundle branch block-induced cardiac remodeling predicts reverse remodeling after cardiac resynchronization therapy

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
S Calle ◽  
J Duchenne ◽  
A Puvrez ◽  
J De Pooter ◽  
J U Voigt ◽  
...  
Keyword(s):  
Cardiac Resynchronization Therapy ◽  
Left Bundle Branch Block ◽  
Speckle Tracking ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Resynchronization Therapy ◽  
Bundle Branch Block ◽  
Systolic Volume ◽  
End Systolic Volume ◽  
Volumetric Response

Abstract Background Left bundle branch block (LBBB)-induced adverse remodeling is a gradual but largely unknown process, causing a variable degree of left ventricular (LV) dysfunction and response to cardiac resynchronization therapy (CRT). In LBBB patients with septal flash (SF), an electro-mechanical continuum of different speckle-tracking strain patterns was observed, with each pattern tightly correlating with the degree of LV remodeling and dysfunction (1) (Figure 1). Purpose In this study, we investigated the relationship between the staged LBBB strain patterns in CRT-eligible patients and their prediction with respect to reverse remodeling and clinical outcome. Methods This study enrolled CRT patients from the PREDICT-CRT study population (2). Inclusion criteria were LV ejection fraction (LVEF) ≤35%, QRS duration ≥120 ms, NYHA class II–IV, absence of right ventricular pacing and availability of speckle tracking strain imaging. All patients underwent an echocardiographic examination before and 12 months after CRT implant. LV volumes, strain and dyssynchrony were assessed. Mid-septal longitudinal strain curves were classified into 5 patterns (LBBB-0 through LBBB-4; Figure 1). Primary endpoint was all-cause mortality. Results The study involved 250 patients (mean age 64±10 years; 79% men) with a mean LVEF of 26±7%. LBBB was present in 220 (89%) patients and 206 (82%) patients had SF. Prior to CRT implant, a LBBB-0 pattern was observed in 33 (13%), LBBB-1 in 33 (13%), LBBB-2 in 39 (16%), LBBB-3 in 44 (18%) and LBBB-4 in 101 (40%) patients. Patients with LBBB-3 and -4 patterns more frequently had LBBB, lower LVEF, increased mechanical dyssynchrony and more prominent SF (p&lt;0.001 for all) compared with patients with LBBB-0, -1 and -2 patterns. Across the stages, CRT resulted in a gradual volumetric response, ranging from no response in stage LBBB-0 patients (ΔLV end-systolic volume +7±33%; ΔLVEF −2±9%) to super-response in stage LBBB-4 patients (ΔLV end-systolic volume −40±29%; ΔLVEF +15±13%) (p&lt;0.001 for all). Interestingly, following reverse remodeling, the LV function of stage LBBB-2, -3 and -4 patients improved to a similar LVEF of 38% (p=1.000) in this cohort. Patients in stage LBBB-0 had a significantly less favorable five-year outcome compared to those in stage LBBB≥1 (log-rank p=0.003). There was no difference in long-term outcome between stage LBBB-1 to −4 patients (log-rank p=0.510). Conclusion Strain-based LBBB staging predicts the extent of LV reverse remodeling in CRT patients. CRT did not translate into improved absolute survival in the more advanced stages, but the observed gradual volumetric response suggests that CRT corrects the LBBB-induced mortality. FUNDunding Acknowledgement Type of funding sources: None. Figure 1

Mechanical discoordination rather than dyssynchrony predicts reverse remodeling upon cardiac resynchronization

2008 ◽  
Vol 295 (2) ◽  
pp. H640-H646 ◽  
Author(s):  
Borut Kirn ◽  
Annemieke Jansen ◽  
Frank Bracke ◽  
Berry van Gelder ◽  
Theo Arts ◽  
...  
Keyword(s):  
Mechanical Dyssynchrony ◽  
Left Ventricular ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Systolic Volume ◽  
Time To Peak ◽  
End Diastolic Volume ◽  
Before And After ◽  
End Systolic Volume ◽  
Time To Onset

By current guidelines a considerable part of the patients selected for cardiac resynchronization therapy (CRT) do not respond to the therapy. We hypothesized that mechanical discoordination [opposite strain within the left ventricular (LV) wall] predicts reversal of LV remodeling upon CRT better than mechanical dyssynchrony. MRI tagging images were acquired in CRT candidates ( n = 19) and in healthy control subjects ( n = 9). Circumferential strain (εcc) was determined in 160 regions. From εcc signals we derived 1) an index of mechanical discoordination [internal stretch fraction (ISF), defined as the ratio of stretch to shortening during ejection] and 2) indexes of mechanical dyssynchrony: the 10–90% width of time to onset of shortening, time to peak shortening, and end-systolic strain. LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) were determined before and after 3 mo of CRT. Responders were defined as those patients in whom LVESV decreased by >15%. In responders ( n = 10), CRT increased LVEF and decreased LVEDV and LVESV (11 ± 6%, 21 ± 16%, and 30 ± 16%, respectively) significantly more ( P < 0.05) than in nonresponders (1 ± 6%, 3 ± 4%, and 5 ± 10%, respectively). Among mechanical indexes, only ISF was different between responders and nonresponders (0.53 ± 0.25 vs. 0.31 ± 0.16; P < 0.05). In patients with ISF >0.4 ( n = 10), LVESV decreased by 31 ± 18% vs. 5 ± 11% in patients with ISF <0.4 ( P < 0.05). We conclude that mechanical discoordination, as estimated from ISF, is a better predictor of reverse remodeling after CRT than differences in time to onset and time to peak shortening. Therefore, discoordination rather than dyssynchrony appears to reflect the reserve contractile capacity that can be recruited by CRT.

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