Assessment of apical rocking: a new, integrative approach for selection of candidates for cardiac resynchronization therapy

Predictive value of apical rocking and septal flash for subclinical left ventricular systolic dysfunction in complete left bundle branch block patients with normal left ventricular ejection fraction

BACKGROUND

This study aimed to evaluate the effects of apical rocking(ApRock) and septal flash(SF) on left ventricular function in complete left bundle branch block(CLBBB) patients with normal left ventricular ejection fraction(LVEF), with the goal of improving risk stratification and clinical decision-making for these patients.

METHODS

Seventy-five CLBBB patients with normal LVEF, and 30 age- and sex-matched controls were enrolled in the study. Three independent physicians visually assessed the presence of ApRock and SF and left ventricular global longitudinal strain(LVGLS) and the standard deviation of time-to-peak strain in 18 segments(Ts-SD) were evaluated using two-dimensional speckle-tracking echocardiography.

RESULTS

CLBBB patients with normal LVEF had significantly decreased LV function and synchrony as evidenced by LVGLS and Ts-SD, and CLBBB patients with either ApRock or SF had lower LVGLS than those without ApRock or SF. LVGLS were further decreased and Ts-SD was further increased in CLBBB patients with both ApRock and SF (P < 0.001). Logistic regression analysis revealed that both ApRock (OR, 4.13; P = 0.04) and SF (OR, 4.12; P = 0.03) were independently associated with LVGLS>-20 %. Combination of ApRock and SF showed the highest area under the curve for identifying LVGLS>-20 %. Furthermore, combination of ApRock and SF improved reclassification compared to ApRock alone.

CONCLUSION

CLBBB patients with normal LVEF showed impaired left ventricular systolic function. The presence of both ApRock and SF was a stronger indicator of subclinical left ventricular impairment compared to either one alone, suggesting that increased attention should be paid to CLBBB patients with normal LVEF, particularly those with both ApRock and SF.

Mechanical dyssynchrony as a selection criterion for cardiac resynchronization therapy: Design of the AMEND-CRT trial

AIMS

One third of patients do not improve after cardiac resynchronization therapy (CRT). Septal flash (SF) and apical rocking (ApRock) are deformation patterns observed on echocardiography in most patients eligible for CRT. These markers of mechanical dyssynchrony have been associated to improved outcome after CRT in observational studies and may be useful to better select patients. The aim of this trial is to investigate whether the current guideline criteria for selecting patients for CRT should be modified and include SF and ApRock to improve therapy success rate, reduce excessive costs and prevent exposure to device-related complications in patients who would not benefit from CRT.

METHODS

The AMEND-CRT trial is a multicentre, randomized, parallel-group, double-blind, sham-controlled trial with a non-inferiority design. The trial will include 578 patients scheduled for CRT according to the 2021 ESC guidelines who satisfy all inclusion criteria. The randomization is performed 1:1 to an active control arm ('guideline arm') or an experimental arm ('echo arm'). All participants receive a device, but in the echo arm, CRT is activated only when SF or ApRock or both are present. The outcome of both arms will be compared after 1 year. The primary outcome measures are the average change in left ventricular end-systolic volume and patient outcome assessed using a modified Packer Clinical Composite Score.

CONCLUSIONS

The findings of this trial will redefine the role of echocardiography in CRT and potentially determine which patients with heart failure and a prolonged QRS duration should receive CRT, especially in patients who currently have a class IIa or class IIb recommendation.

Outcomes with T-wave discordance of left bundle branch block and preserved or mildly reduced ejection fraction

AIMS

Left bundle branch block (LBBB) is associated with an increased risk of adverse outcomes for patients with heart failure. The prognosis of LBBB in patients with a preserved ejection fraction (EF) remains controversial. This study investigated the predictive value of T-wave discordance for the prognosis of patients with LBBB and preserved or mildly reduced EF.

METHODS AND RESULTS

We enrolled 707 patients with complete LBBB and left ventricular (LV) EF ≥ 40% observed using electrocardiograms (ECGs) and echocardiograms between January 2010 and December 2018. Their serial ECGs were reviewed during the follow-up period. The T-wave pattern was classified as discordant LBBB (dLBBB) or concordant LBBB (cLBBB) according to the 12-lead ECG T-wave morphology. The primary outcome was the composite of cardiovascular death or hospitalization for heart failure during a median follow-up period of 3.1 years. A multivariable Cox regression analysis was used to evaluate the independent predictors of the primary outcome. Patients with dLBBB had more comorbidities, a higher heart rate, a longer QRS and QTc duration, a larger LV end-systolic volume and left atrial dimension, a lower LVEF, and a higher mitral E/A ratio and E/e', compared with those with cLBBB. Older age [hazard ratio (HR) = 1.023, 95% confidence interval (CI) = 1.001-1.046, P = 0.023], history of heart failure (HR = 2.440, 95% CI = 1.524-3.905, P = 0.001), chronic kidney disease (HR = 1.917, 95% CI = 1.182-3.110, P = 0.008), larger LV end-systolic volume (HR = 1.046, 95% CI = 1.017-1.075, P = 0.002), lower LVEF (HR = 0.916, 95% CI = 0.885-0.948, P = 0.001), and presence of dLBBB (HR = 1.63, 95% CI = 1.011-2.628, P = 0.032) were independent predictors of the primary outcome in patients with LBBB and LVEF ≥ 40%. The discordant or concordant T-wave morphology of LBBB could transform from one subtype to the other in up to 23% of the study population during the follow-up period, and individuals with persistent or transformed dLBBB faced an increased risk of cardiovascular death or non-fatal heart failure hospitalization.

CONCLUSIONS

In patients with LBBB and EF ≥ 40%, dLBBB serves as an independent predictor of a higher risk of cardiovascular death or non-fatal heart failure hospitalization.

A Comparative Analysis of Apical Rocking and Septal Flash: Two Views of the Same Systole?

Heart failure (HF) is a complex medical condition characterized by both electrical and mechanical dyssynchrony. Both dyssynchrony mechanisms are intricately linked together, but the current guidelines for cardiac resynchronization therapy (CRT) rely only on the electrical dyssynchrony criteria, such as the QRS complex duration. This possible inconsistency may result in undertreating eligible individuals who could benefit from CRT due to their mechanical dyssynchrony, even if they fail to fulfill the electrical criteria. The main objective of this literature review is to provide a comprehensive analysis of the practical value of echocardiography for the assessment of left ventricular (LV) dyssynchrony using parameters such as septal flash and apical rocking, which have proven their relevance in patient selection for CRT. The secondary objectives aim to offer an overview of the relationship between septal flash and apical rocking, to emphasize the primary drawbacks and benefits of using echocardiography for evaluation of septal flash and apical rocking, and to offer insights into potential clinical applications and future research directions in this area. Conclusion: there is an opportunity to render resynchronization therapy more effective for every individual; septal flash and apical rocking could be a very useful and straightforward echocardiography resource.

Role of speckle tracking echocardiography beyond current guidelines in cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is a device-based treatment applied to patients with a specific profile of heart failure. According to current guidelines, indication for CRT is given on the basis of QRS morphology and duration, and traditional transthoracic echocardiography is mainly used to estimate left ventricular (LV) ejection fraction. However, the identification of patients who may benefit from CRT remains challenging, since the application of the above-mentioned guidelines is still associated with a high rate of non-responders. The assessment of various aspects of LV mechanics (including contractile synchrony, coordination and propagation, and myocardial work) performed by conventional and novel ultrasound technologies, first of all speckle tracking echocardiography (STE), may provide additional, useful information for CRT patients' selection, in particular among non-LBBB patients, who generally respond less to CRT. A multiparametric approach, based on the combination of ECG criteria and echocardiographic indices of LV dyssynchrony/discoordination would be desirable to improve the prediction of CRT response.

Understanding the Application of Mechanical Dyssynchrony in Patients with Heart Failure Considered for CRT

Over the past two decades of CRT use, the failure rate has remained around 30-35%, despite several updates in the guidelines based on the understanding from multiple trials. This review article summarizes the role of mechanical dyssynchrony in the selection of heart failure patients for cardiac resynchronization therapy. Understanding the application of mechanical dyssynchrony has also evolved during these past two decades. There is no role of lone mechanical dyssynchrony in the patient selection for CRT. However, mechanical dyssynchrony can complement the electrocardiogram and clinical criteria and improve patient selection by reducing the failure rate. An oversimplified approach to mechanical dyssynchrony assessment, such as just estimating time-to-peak delays between segments, should not be used. Instead, methods that can identify the underlying pathophysiology of HF and are representative of a substrate to CRT should be applied.

Echocardiographic mechanical dyssynchrony predicts long-term mortality in patients with cardiac resynchronisation therapy

Cardiac resynchronisation therapy (CRT) is an established treatment for patients with symptomatic heart failure with reduced left ventricular ejection fraction (LVEF ≤ 35%; HFrEF) and conduction disturbances (QRS duration ≥ 130 ms). The presence of mechanical dyssynchrony (MD) on echocardiography has been hypothesised to be of predictive value in determining indication for CRT. This study investigated the impact of MD (apical rocking [AR] and septal flash [SF]) on long-term survival in CRT recipients. HFrEF patients (n = 425; mean age 63.0 ± 10.6 years, 72.3% male, 60.7% non-ischaemic aetiology) with a guideline-derived indication for CRT underwent device implantation. MD markers were determined at baseline and after a mean follow-up of 11.5 ± 8.0 months; long-term survival was also determined. AR and/or SF were present in 307 (72.2%) participants at baseline. During post-CRT follow-up, AR and/or SF disappeared in 256 (83.4%) patients. Overall mean survival was 95.9 ± 52.9 months, longer in women than in men (109.1 ± 52.4 vs. 90.9 ± 52.4 months; p < 0.001) and in younger (< 60 years) versus older patients (110.6 ± 53.7 vs. 88.6 ± 51.1 months; p < 0.001). Patients with versus without MD markers at baseline generally survived for longer (106.2 ± 52.0 vs. 68.9 ± 45.4 months; p < 0.001), and survival was best in patients with resolved versus persisting MD (111.6 ± 51.2 vs. 79.7 ± 47.6 months p < 0.001). Age and MD at baseline were strong predictors of long-term survival in HFrEF patients undergoing CRT on multivariate analysis. Novel echocardiography MD parameters in HFrEF CRT recipients predicted long-term mediated better outcome, and survival improved further when AR and/or SF disappear after CRT implantation.

Imaging in patients with cardiovascular implantable electronic devices: part 1-imaging before and during device implantation. A clinical consensus statement of the European Association of Cardiovascular Imaging (EACVI) and the European Heart Rhythm Association (EHRA) of the ESC

More than 500 000 cardiovascular implantable electronic devices (CIEDs) are implanted in the European Society of Cardiology countries each year. The role of cardiovascular imaging in patients being considered for CIED is distinctly different from imaging in CIED recipients. In the former group, imaging can help identify specific or potentially reversible causes of heart block, the underlying tissue characteristics associated with malignant arrhythmias, and the mechanical consequences of conduction delays and can also aid challenging lead placements. On the other hand, cardiovascular imaging is required in CIED recipients for standard indications and to assess the response to device implantation, to diagnose immediate and delayed complications after implantation, and to guide device optimization. The present clinical consensus statement (Part 1) from the European Association of Cardiovascular Imaging, in collaboration with the European Heart Rhythm Association, provides comprehensive, up-to-date, and evidence-based guidance to cardiologists, cardiac imagers, and pacing specialists regarding the use of imaging in patients undergoing implantation of conventional pacemakers, cardioverter defibrillators, and resynchronization therapy devices. The document summarizes the existing evidence regarding the use of imaging in patient selection and during the implantation procedure and also underlines gaps in evidence in the field. The role of imaging after CIED implantation is discussed in the second document (Part 2).

Congenital anomalous drainage of the inferior vena cava and hepatic veins into the left atrium associated with long QT syndrome: Multimodality imaging, pitfalls, and caveats

Isolated congenital anomalous drainage of the inferior vena cava (IVC) and partial hepatic veins (HV) into the left atrium (LA) via an interatrial communication (IAC), associated with the normal connection of the IVC to the right atrium is exceedingly rare. Therefore, there is a dearth of knowledge regarding the management of these cases. To date, there has been no report of abnormal IVC drainage caused by abnormal IVC-IAC alignment. Much more frequently, patients have an abnormal connection or abnormal drainage mediated by a persistent Eustachian valve that allows blood to pass from the inferior vena cava to the left atrium. Herein, we report an 8-year-old boy with anomalous IVC and hepatic vein drainage into the LA due to IVC-IAC malalignment. We describe the findings of multimodality imaging, including transthoracic, transesophageal, contrast, and speckle-tracking echocardiography, cardiac angiography, and cardiac magnetic resonance imaging. We go over the diagnostic and therapeutic pitfalls and caveats of this case that can apply to similar patients.

Soft tissue displacement for detection of left ventricle apical dyskinesis with transthoracic echocardiography

We tested the hypothesis that the use of outward displacement of the soft tissue between the apex and the chest wall as seen in TTE, is a sign of apical displacement and would allow for more accurate diagnosis of apical dyskinesis. This is a retrospective study of 123 patients who underwent TTE and cardiac magnetic resonance imaging (MRI) within a time frame of 6 months between 2008 and 2019. 110 subjects were deemed to have good quality studies and included in the final analysis. An observer blinded to the study objectives evaluated the echocardiograms and recorded the presence or absence of apical dyskinesis. Two independent observers evaluated the echocardiograms based on the presence or absence of outward displacement of the overlying tissue at the LV apex. Cardiac MRI was used to validate the presence of apical dyskinesis. The proportion of studies which were identified as having apical dyskinesis with conventional criteria defined as outward movement of the left ventricular apex during systole were compared to those deemed to have dyskinesis based on tissue displacement. By cardiac MRI, 90 patients had apical dyskinesis. Using conventional criteria on TTE interpretation, 21 were diagnosed with apical dyskinesis (23.3%). However, when soft tissue displacement was used as the diagnostic marker of dyskinesis, 78 patients (86.7%) were diagnosed with dyskinesis, p < 0.01. Detection of displacement of soft tissue overlying the LV apex facilitates better recognition of LV apical dyskinesis.

Dyssynchronous Heart Failure: A Clinical Review

PURPOSE OF THE REVIEW

Dyssynchrony occurs when portions of the cardiac chambers contract in an uncoordinated fashion. Ventricular dyssynchrony primarily impacts the left ventricle and may result in heart failure. This entity is recognized as a major contributor to the development and progression of heart failure. A hallmark of dyssynchronous heart failure (HF_d) is left ventricular recovery after dyssynchrony is corrected. This review discusses the current understanding of pathophysiology of HF_d and provides clinical examples and current techniques for treatment.

RECENT FINDINGS

Data show that HF_d responds poorly to medical therapy. Cardiac resynchronization therapy (CRT) in the form of conventional biventricular pacing (BVP) is of proven benefit in HF_d, but is limited by a significant non-responder rate. Recently, conduction system pacing (His bundle or left bundle branch area pacing) has also shown promise in correcting HF_d. HF_d should be recognized as a distinct etiology of heart failure; HF_d responds best to CRT.

COVID-19-induced silent myocarditis and newly developed hypertension in a 3-year-old boy

BACKGROUND

COVID-19 myocarditis occurs in 7-28% of patients admitted in the hospital with or without multisystem inflammatory syndrome. It may present as fulminant myocarditis. Dilated cardiomyopathy as a sequela of COVID-19 myocarditis has been reported in the pediatric population. However, to date, no case of silent COVID-19 myocarditis progressing to dilated cardiomyopathy has been reported in children. Furthermore, although newly developed hypertension as a sequela of COVID-19 infection has been reported in adults, there is no report of newly developed COVID-induced hypertension in children. We report a 3-year-old boy with silent COVID-19 myocarditis progressing to dilated cardiomyopathy and newly developed systemic hypertension.

CASE PRESENTATION

A 3-year-old boy was referred to the emergency department because of respiratory distress. The parents gave a history of SARS-CoV-2 infection in the child 5 months ago that was manifested as fever and cough, for which he was treated as an outpatient. Echocardiographic examination revealed a severe decrease in left ventricular systolic function in favor of dilated cardiomyopathy. Cardiac magnetic resonance imaging established the diagnosis of myocarditis. The patient left ventricular systolic function did not improve after 2 weeks of intravenous inotropic support. Therefore, the child was transferred to another tertiary center with extracorporeal membrane oxygenation and pediatric cardiac transplantation facilities.

CONCLUSIONS

COVID-19 can induce silent myocarditis with progression to dilated cardiomyopathy and newly developed systemic hypertension. Thus, a thorough examination of the heart and measurement of blood pressure are mandatory in every child with COVID-19 infection. Cardiac MR is an indispensable tool in the diagnosis, follow-up, and prognostication of COVID-19 myocarditis. Moreover, four-chamber speckle tracking strain imaging showed apical rocking in all the four heart chambers in this child with opposite direction in the failed left ventricle compared with other cardiac chambers. Lastly, the presence of septal flash on M-mode echocardiography, apical rocking and prestretch-rebound stretch patterns on longitudinal strain imaging of the failed left ventricle in this child may be of predictive value for response to cardiac resynchronization therapy.

Echocardiographic Advances in Dilated Cardiomyopathy

Although the overall survival of patients with dilated cardiomyopathy (DCM) has improved significantly in the last decades, a non-negligible proportion of DCM patients still shows an unfavorable prognosis. DCM patients not only need imaging techniques that are effective in diagnosis, but also suitable for long-term follow-up with frequent re-evaluations. The exponential growth of echocardiography’s technology and performance in recent years has resulted in improved diagnostic accuracy, stratification, management and follow-up of patients with DCM. This review summarizes some new developments in echocardiography and their promising applications in DCM. Although nowadays cardiac magnetic resonance (CMR) remains the gold standard technique in DCM, the echocardiographic advances and novelties proposed in the manuscript, if properly integrated into clinical practice, could bring echocardiography closer to CMR in terms of accuracy and may certify ultrasound as the technique of choice in the follow-up of DCM patients. The application in DCM patients of novel echocardiographic techniques represents an interesting emergent research area for scholars in the near future.

The value of septal rebound stretch analysis for the prediction of volumetric response to cardiac resynchronization therapy

AIMS

Patient selection for cardiac resynchronization therapy (CRT) may be enhanced by evaluation of systolic myocardial stretching. We evaluate whether systolic septal rebound stretch (SRSsept) derived from speckle tracking echocardiography is a predictor of reverse remodelling after CRT and whether it holds additive predictive value over the simpler visual dyssynchrony assessment by apical rocking (ApRock).

METHODS AND RESULTS

The association between SRSsept and change in left ventricular end-systolic volume (ΔLVESV) at 6 months of follow-up was assessed in 200 patients. Subsequently, the additive predictive value of SRSsept over the assessment of ApRock was evaluated in patients with and without left bundle branch block (LBBB) according to strict criteria. SRSsept was independently associated with ΔLVESV (β 0.221, P = 0.002) after correction for sex, age, ischaemic cardiomyopathy, QRS morphology and duration, and ApRock. A high SRSsept (≥optimal cut-off value 2.4) also coincided with more volumetric responders (ΔLVESV ≥ -15%) than low SRSsept in the entire cohort (70.0% and 56.4%), in patients with strict LBBB (83.3% vs. 56.7%, P = 0.024), and non-LBBB (70.7% vs. 46.3%, P = 0.004). Moreover, in non-LBBB patients, SRSsept held additional predictive information over the assessment of ApRock alone since patients that showed ApRock and high SRSsept were more often volumetric responder than those with ApRock but low SRSsept (82.8% vs. 47.4%, P = 0.001).

CONCLUSION

SRSsept is strongly associated with CRT-induced reduction in left ventricular end-systolic volume and holds additive prognostic information over QRS morphology and ApRock. Our data suggest that CRT patient selection may be improved by assessment of SRSsept, especially in the important subgroup without strict LBBB.

CLINICAL TRIAL REGISTRATION

The MARC study was registered at clinicaltrials.gov: NCT01519908.

Current Role of Echocardiography in Cardiac Resynchronization Therapy: from Cardiac Mechanics to Flow Dynamics Analysis

PURPOSE OF REVIEW

The aim of this review is to summarily explain what LV synchrony, coordination, myocardial work, and flow dynamics are, trying to clarify their advantages and limitations in the treatment of heart failure patients undergoing or with implanted cardiac resynchronization therapy (CRT).

RECENT FINDINGS

CRT is an established treatment for patients with heart failure and left ventricular systolic dysfunction. In the current guidelines, CRT implant indications rely only on electrical dyssynchrony, but in the last years, many aspects of cardiac mechanics (including contractile synchrony, coordination, propagation, and myocardial work) and flow dynamics have been studied using echocardiographic techniques to better characterize patients undergoing or with implanted CRT. However, the concepts, limits, and potential applications of all these echocardiographic evaluations are unclear to most clinicians. The use of left ventricular dyssynchrony and discoordination indices may help to identify those significant mechanical alterations whose correction may increase the probability of a favorable CRT response. Assessment of myocardial work and intracardiac flow dynamics may overcome some limitations of the conventional evaluation of cardiac mechanics but more investigations are needed before extensive clinical application.

Segment length in cine (SLICE) strain analysis: a practical approach to estimate potential benefit from cardiac resynchronization therapy

BACKGROUND

Segment length in cine (SLICE) strain analysis on standard cardiovascular magnetic resonance (CMR) cine images was recently validated against gold standard myocardial tagging. The present study aims to explore predictive value of SLICE for cardiac resynchronization therapy (CRT) response.

METHODS AND RESULTS

Fifty-seven patients with heart failure and left bundle branch block (LBBB) were prospectively enrolled in this multi-center study and underwent CMR examination before CRT implantation. Circumferential strains of the septal and lateral wall were measured by SLICE on short-axis cine images. In addition, timing and strain pattern parameters were assessed. After twelve months, CRT response was quantified by the echocardiographic change in left ventricular (LV) end-systolic volume (LVESV). In contrast to timing parameters, strain pattern parameters being systolic rebound stretch of the septum (SRSsep), systolic stretch index (SSIsep-lat), and internal stretch factor (ISFsep-lat) all correlated significantly with LVESV change (R - 0.56; R - 0.53; and R - 0.58, respectively). Of all strain parameters, end-systolic septal strain (ESSsep) showed strongest correlation with LVESV change (R - 0.63). Multivariable analysis showed ESSsep to be independently related to LVESV change together with age and QRSAREA.

CONCLUSION

The practicable SLICE strain technique may help the clinician to estimate potential benefit from CRT by analyzing standard CMR cine images without the need for commercial software. Of all strain parameters, end-systolic septal strain (ESSsep) demonstrates the strongest correlation with reverse remodeling after CRT. This parameter may be of special interest in patients with non-strict LBBB morphology for whom CRT benefit is doubted.

Acute redistribution of regional left ventricular work by cardiac resynchronization therapy determines long-term remodelling

Aims 

Investigating the acute impact of cardiac resynchronization therapy (CRT) on regional myocardial work distribution in the left ventricle (LV) and to which extent it is related to long-term reverse remodelling.

Methods and results 

One hundred and thirty heart failure patients, referred for CRT implantation, were recruited in our prospective multicentre study. Regional myocardial work was calculated from non-invasive segmental stress–strain loop area before and immediately after CRT. The magnitude of volumetric reverse remodelling was determined from the change in LV end-systolic volume, 11 ± 2 months after implantation. CRT caused acute redistribution of myocardial work across the LV, with an increase in septal work, and decrease in LV lateral wall work (all P &lt; 0.05). Amongst all LV walls, the acute change in work in the septum and lateral wall of the four-chamber view correlated best and significantly with volumetric reverse remodelling (r = 0.62, P &lt; 0.0001), with largest change seen in patients with most volumetric reverse remodelling. In multivariate linear regression analysis, including conventional parameters, such as pre-implant QRS morphology and duration, LV ejection fraction, ischaemic origin of cardiomyopathy, and the redistribution of work across the septal and lateral walls, the latter appeared as the strongest determinant of volumetric reverse remodelling after CRT (model R2 = 0.414, P &lt; 0.0001).

Conclusion 

The acute redistribution of regional myocardial work between the septal and lateral wall of the LV is an important determinant of reverse remodelling after CRT implantation. Our data suggest that the treatment of the loading imbalance should, therefore, be the main aim of CRT.

Myocardial work is a predictor of exercise tolerance in patients with dilated cardiomyopathy and left ventricular dyssynchrony

The assessment of myocardial work (MW) by pressure-strain loops is a recently introduced tool for the assessment of myocardial performance. Aim of the present study is to evaluate the relationship between myocardial work and exercise tolerance in patients with dilated cardiomyopathy (DCM). 51 patients with DCM (mean age 57 ± 13 years, left ventricular ejection fraction: 32 ± 9%) underwent cardiopulmonary exercise test (CPET) to assess exercise performance. 22 patients (43%) had left or right bundle branch block with QRS duration > 120 ms. Trans-thoracic echocardiography (TTE) was performed before CPET. The following indices of myocardial work (MW) were measured regionally and globally: constructive work (CW), wasted work (WW), and work efficiency (WE). Left ventricular dyssynchrony (LV-DYS) was defined by the presence of septal flash or apical rocking at TTE. LV-DYS was observed in 16 (31%) patients and associated with lower LV ejection fraction (LVEF), lower global and septal WE, and higher global and septal WW. In patients with LV-DYS, septal WE was the only predictor of exercise capacity at multivariable analysis (β = 0.68, p = 0.03), whereas LVEF (β = 0.47, p = 0.05) and age (β = - 0.42, p = 0.04) were predictors of exercise capacity in patients without LV-DYS. In patients with DCM, LV-DYS is associated with an heterogeneous distribution of myocardial work. Septal WE is the best predictor of exercise performance in these patients.

Successful biventricular cardiac resynchronization therapy in a failing Fontan patient: Implications of ventriculo-ventricular interdependency in single ventricle physiology

We describe a Fontan patient with severe heart failure who was successfully treated with biventricular cardiac resynchronization therapy (CRT). Our case shows that strain imaging might play a crucial role in guiding placement of pacing leads and in characterizing the electromechanical substrate associated with a favorable CRT response. Furthermore, we demonstrate for the first time that ventriculo-ventricular interdependency seems an important mechanical concept, which can be utilized to augment cardiac performance in failing Fontan patients with a functional hypoplastic ventricle.

Cardiac Resynchronization Therapy Optimization: A Comprehensive Approach

Since the first report on biventricular pacing in 1994, cardiac resynchronization therapy (CRT) has become standard for patients with advanced heart failure (HF) and ventricular conduction delay. CRT improves myocardial function by resynchronizing myocardial contraction, which results in reverse left ventricular remodeling and improves symptoms and clinical outcomes. Despite the accelerated development of CRT device technology and its increased application in treating HF patients, almost one-third of these patients do not respond to the therapy or gain any clinical benefit from device implantation. Over the last decade, multiple cardiac imaging modalities have provided a deeper understanding of myocardial pathophysiology, thereby improving HF treatment management. However, the optimal strategy for improving the CRT response remains debatable. This article provides an updated overview of the electropathophysiology of myocardial dysfunction in ventricular conduction delay and the diagnostic approaches involving the use of multiple modalities.

The Association of a classical left bundle Branch Block Contraction Pattern by vendor-independent strain echocardiography and outcome after cardiac resynchronization therapy

Background

The association of a Classical left bundle branch block (LBBB) contraction pattern and better outcome after cardiac resynchronization therapy (CRT) has only been studied using vendor-specific software for echocardiographic speckle-tracked longitudinal strain analysis. The purpose of this study was to assess whether a Classical LBBB contraction pattern on longitudinal strain analysis using vendor-independent software is associated with clinical outcome in CRT recipients with LBBB.

Methods

This was a retrospective cohort study including CRT recipients with LBBB, heart failure, and left ventricular (LV) ejection fraction ≤35%. Speckle-tracked echocardiographic longitudinal strain analysis was performed retrospectively on echocardiograms using vendor-independent software. The presence of a Classical LBBB contraction pattern was determined by consensus of two readers. The primary end point was a composite of time to death, heart transplantation or LV assist device implantation. Secondary outcome was ≥15% reduction in LV end-systolic volume. Intra- and inter-reader agreement of the longitudinal strain contraction pattern was assessed by calculating Cohen’s κ.

Results

Of 283 included patients, 113 (40%) were women, mean age was 66 ± 11 years, and 136 (48%) had ischemic heart disease. A Classical LBBB contraction pattern was present in 196 (69%). The unadjusted hazard ratio for reaching the primary end point was 1.93 (95% confidence interval, 1.36–2.76, p < 0.001) when comparing patients without to patients with a Classical LBBB contraction pattern. Adjusted for ischemic heart disease and QRS duration < 150 milliseconds the hazard ratio was 1.65 (95% confidence interval, 1.12–2.43, p = 0.01). Of the 123 (43%) patients with a follow-up echocardiogram, 64 of 85 (75%) of patients with a Classical LBBB contraction pattern compared to 13 of 38 (34%) without, had ≥15% reduction in LV end-systolic volume (p < 0.001). Cohen’s κ were 0.86 (95% confidence interval, 0.71–1.00) and 0.42 (95% confidence interval, 0.30–0.54) for intra- and inter-reader agreement, respectively.

Conclusion

Using vendor-independent strain software, a Classical LBBB contraction pattern is associated with better outcome in CRT recipients with LBBB, but inter-reader agreement for the classification of contraction pattern is only moderate.

Echocardiography for prediction of 6-month and late response to cardiac resynchronization therapy: implementation of stress echocardiography and comparative assessment along with widely used dyssynchrony indices

Non-response cardiac resynchronization therapy (CRT) remains an issue, despite the refinement of selection criteria. The purpose of this study was to investigate the role of stress echocardiography along with dyssynchrony parameters for identification of CRT responders or late responders. 106 symptomatic heart failure patients were examined before, 6 months and 2-4 years after CRT implementation. Inotropic contractile reserve (ICR) and inferolateral (IL) wall viability were studied by stress echocardiography. Dyssynchrony was assessed by: (1) Septal to posterior wall motion delay (SPWMD) by m-mode. (2) Septal to lateral wall delay (SLD) by TDI. (3) Interventricular mechanical delay (IVMD) by pulsed wave Doppler for (4) difference in time to peak circumferential strain (TmaxCS) by speckle tracking. (5) Apical rocking (ApR) and septal flash (SF) by visual assessment. At 6 months there were 54 responders, with 12 additional late responders. TmaxCS had the greatest predictive value with an area under curve (AUC) of 0.835, followed by the presence of both ICR and viability of IL wall (AUC 0.799), m-mode (AUC = 0.775) and presence of either ApR or SF (AUC = 0.772). Predictive ability of ApR and of ICR is augmented if late responders are also included. Performance of dyssynchrony parameters is enhanced, in patients with both ICR and IL wall viability. Stress echocardiography and dyssynchrony parameters are simple and reliable predictors of 6-month and late CRT response. A stepwise approach with an initial assessment of ICR and viability and, if positive, further dyssynchrony analysis, could assist decision making.

Rational and design of EuroCRT: an international observational study on multi-modality imaging and cardiac resynchronization therapy

Aims

Assessment of left ventricular (LV) volumes and ejection fraction (LVEF) with cardiac imaging is important in the selection of patients for cardiac resynchronization therapy (CRT). Several observational studies have explored the role of imaging-derived LV dyssynchrony parameters to predict the response to CRT, but have yielded inconsistent results, precluding the inclusion of imaging-derived LV dyssynchrony parameters in current guidelines for selection of patients for CRT.

Methods

The EuroCRT is a large European multicentre prospective observational study led by the European Association of Cardiovascular Imaging. We aim to explore if combing the value of cardiac magnetic resonance (CMR) and echocardiography could be beneficial for selecting heart failure patients for CRT in terms of improvement in long-term survival, clinical symptoms, LV function, and volumes. Speckle tracking echocardiography will be used to assess LV dyssynchrony and wasted cardiac work whereas myocardial scar will be assessed with late gadolinium contrast enhanced CMR. All data will be measured in core laboratories. The study will be conducted in European centres with known expertise in both CRT and multimodality cardiac imaging.

Current role of echocardiography in cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure and left ventricular systolic dysfunction. Patients are usually assessed by echocardiography, which provides a number of anatomical and functional information used for cardiac dyssynchrony assessment, prognostic stratification, identification of the optimal site of pacing in the left ventricle, optimization of the CRT device, and patient follow-up. Compared to other cardiac imaging techniques, echocardiography has the advantage to be non-invasive, repeatable, and safe, without exposure to ionizing radiation or nefrotoxic contrast. In this article, we review current evidence about the role of echocardiography before, during, and after the implantation of a CRT device.

Echocardiographic evaluation of cardiac dyssynchrony: Does it still matter?

Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure and left ventricular systolic dysfunction. For many years, cardiac mechanical dyssynchrony assessed by echocardiography has been considered as a key evaluation to characterize CRT candidates and predict CRT response. In current guidelines, however, CRT implant indications rely only on electrical dyssynchrony. The aim of this article was to clarify whether and how the evaluation of cardiac mechanical dyssynchrony should be performed today by echocardiography.

Mechanical dispersion is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks

OBJECTIVES

Bundle branch blocks (BBB)-related mechanical dyssynchrony and dispersion may improve patient selection for device therapy, but their effect on the natural history of this patient population is unknown.

METHODS

A total of 155 patients with LVEF ≤ 35% and BBB, not treated with device therapy, were included. Mechanical dyssynchrony was defined as the presence of either septal flash or apical rocking. Contraction duration was assessed as time interval from the electrocardiographic R-(Q-)wave to peak longitudinal strain in each of 17 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of all time intervals (dispersion_SD) or as the difference between the longest and shortest time intervals (dispersion_delta). Patients were followed for cardiac mortality during a median period of 33 months.

RESULTS

Mechanical dyssynchrony was not associated with survival. More pronounced mechanical dispersion_delta was found in patients with dyssynchrony than in those without. In the multivariate regression analysis, patients' functional class, diabetes mellitus and dispersion_delta were independently associated with mortality.

CONCLUSIONS

Mechanical dispersion, but not dyssynchrony, was independently associated with mortality and it may be useful for risk stratification of patients with heart failure (HF) and BBB. Key Messages Mechanical dispersion, measured by strain echocardiography, is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks. Mechanical dispersion may be useful for risk stratification of patients with heart failure and bundle branch blocks.

Echocardiography for the management of patients with biventricular pacing: Possible roles in cardiac resynchronization therapy implementation

Cardiac resynchronization therapy (CRT) is an established therapeutic option for the subset of patients with heart failure (HF), reduced ejection fraction (EF), and dyssynchrony evidenced by electrocardiography. Benefit from CRT has been proven in many clinical trials, yet a sizeable proportion of these patients with wide QRS do not respond to this intervention, despite the updated practice guidelines. Several echocardiographic indices, targeting mechanical rather than electrical dyssynchrony, have been suggested to address this issue, but research so far has not succeeded in providing a single and simple measurement with adequate sensitivity and specificity for identification of responders. While there is still ongoing research in this field, echocardiography proves helpful in other aspects of CRT implementation, such as site selection for left ventricular (LV) lead pacing and optimization of pacing parameters during follow-up visits.

Refining success of cardiac resynchronization therapy using a simple score predicting the amount of reverse ventricular remodelling: results from the Markers and Response to CRT (MARC) study

Aims

Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in systolic heart failure patients with ventricular conduction delay. Variability of individual response to CRT warrants improved patient selection. The Markers and Response to CRT (MARC) study was designed to investigate markers related to response to CRT.

Methods and results

We prospectively studied the ability of 11 clinical, 11 electrocardiographic, 4 echocardiographic, and 16 blood biomarkers to predict CRT response in 240 patients. Response was measured by the reduction of indexed left ventricular end-systolic volume (LVESVi) at 6 months follow-up. Biomarkers were related to LVESVi change using log-linear regression on continuous scale. Covariates that were significant univariately were included in a multivariable model. The final model was utilized to compose a response score. Age was 67 ± 10 years, 63% were male, 46% had ischaemic aetiology, LV ejection fraction was 26 ± 8%, LVESVi was 75 ± 31 mL/m2, and QRS was 178 ± 23 ms. At 6 months LVESVi was reduced to 58 ± 31 mL/m2 (relative reduction of 22 ± 24%), 130 patients (61%) showed ≥ 15% LVESVi reduction. In univariate analysis 17 parameters were significantly associated with LVESVi change. In the final model age, QRSAREA (using vectorcardiography) and two echocardiographic markers (interventricular mechanical delay and apical rocking) remained significantly associated with the amount of reverse ventricular remodelling. This CAVIAR (CRT-Age-Vectorcardiographic QRSAREA -Interventricular Mechanical delay-Apical Rocking) response score also predicted clinical outcome assessed by heart failure hospitalizations and all-cause mortality.

Conclusions

The CAVIAR response score predicts the amount of reverse remodelling after CRT and may be used to improve patient selection. Clinical Trials: NCT01519908.

Pilot study using 3D-longitudinal strain computation in a multi-parametric approach for best selecting responders to cardiac resynchronization therapy

BACKGROUND

Almost all attempts to improve patient selection for cardiac resynchronization therapy (CRT) using echo-derived indices have failed so far. We sought to assess: the performance of homemade software for the automatic quantification of integral 3D regional longitudinal strain curves exploring left ventricular (LV) mechanics and the potential value of this tool to predict CRT response.

METHODS

Forty-eight heart failure patients in sinus rhythm, referred for CRT-implantation (mean age: 65 years; LV-ejection fraction: 26%; QRS-duration: 160 milliseconds) were prospectively explored. Thirty-four patients (71%) had positive responses, defined as an LV end-systolic volume decrease ≥15% at 6-months. 3D-longitudinal strain curves were exported for analysis using custom-made algorithms. The integrals of the longitudinal strain signals (I _L,peak) were automatically measured and calculated for all 17 LV-segments.

RESULTS

The standard deviation of longitudinal strain peak (SDI _L,peak ) for all 17 LV-segments was greater in CRT responders than non-responders (1.18% s^-1 [0.96; 1.35] versus 0.83% s^-1 [0.55; 0.99], p = 0.007). The optimal cut-off value of SDI _L,peak to predict response was 1.037%.s^-1. In the 18-patients without septal flash, SDI _L,peak was significantly higher in the CRT-responders.

CONCLUSIONS

This new automatic software for analyzing 3D longitudinal strain curves is avoiding previous limitations of imaging techniques for assessing dyssynchrony and then its value will have to be tested in a large group of patients.

Prognostic significance of improvement in right ventricular systolic function during cardiac resynchronization therapy

Objectives There is conflicting evidence concerning the role of right ventricular (RV) systolic dysfunction in the long-term clinical outcome after cardiac resynchronization therapy (CRT). Therefore we aimed to assess evolution of RV systolic function during CRT, covariates associated with its improvement, and its impact on outcome. Methods and results All CRT device implantations (Jan 2009-Dec 2011) in our institution were reviewed. Records of 69 patients (25% female, mean age 62.8 ± 9.2 years, mean left ventricular (LV) ejection fraction 27 ± 8%) were analyzed. Baseline RV fractional area change (FAC) < 35% was present in 37 patients (54%). At one year, 24 of them (65%) improved in RV FAC. LV remodeling and mitral regurgitation were significantly associated with the likelihood of RV FAC improvement (OR 4.80, 95% CI 1.13-20.46, P = 0.034 and OR 0.32, 95% CI 0.12-0.89, P = 0.029, respectively). The composite endpoint of death or heart transplantation occurred in 23 patients (33%) over a mean follow-up of 2.8 ± 1.4 years. RV FAC at one year (HR 0.90, 95% CI 0.86-0.94, P < .001) was, independently of NYHA class and LV remodeling, associated with clinical outcome. Conclusions RV systolic function might improve during CRT. This seems mainly due to changed left-sided hemodynamics and LV remodeling. Good RV systolic function is independently related with better outcome.

Newer Echocardiographic Techniques in Cardiac Resynchronization Therapy

Echocardiographic imaging plays a major role in patient selection for cardiac resynchronization therapy (CRT). One-third of patients do not respond; there is interest in advanced echocardiographic imaging to improve response. Current guidelines favor CRT for patients with electrocardiographic (ECG) QRS width of 150 milliseconds or greater and left bundle branch block. ECG criteria are imperfect; there is interest in advanced echocardiographic imaging to improve patient selection. This discussion focuses on newer echocardiographic methods to improve patient selection, improve delivery, and identify patients at risk for poor outcomes and serious ventricular arrhythmias.

Cardiovascular magnetic resonance features of mechanical dyssynchrony in patients with left bundle branch block

Patients with left bundle branch block (LBBB) can exhibit mechanical dyssynchrony which may contribute to heart failure; such patients may benefit from cardiac resynchronization treatment (CRT). While cardiac magnetic resonance imaging (CMR) has become a common part of heart failure work-up, CMR features of mechanical dyssynchrony in patients with LBBB have not been well characterized. This study aims to investigate the potential of CMR to characterize mechanical features of LBBB. CMR examinations from 43 patients with LBBB on their electrocardiogram, but without significant focal structural abnormalities, and from 43 age- and gender-matched normal controls were retrospectively reviewed. The following mechanical features of LBBB were evaluated: septal flash (SF), apical rocking (AR), delayed aortic valve opening measured relative to both end-diastole (AVO_ED) and pulmonic valve opening (AVO_PVO), delayed left-ventricular (LV) free-wall contraction, and curvatures of the septum and LV free-wall. Septal displacement curves were also generated, using feature-tracking techniques. The echocardiographic findings of LBBB were also reviewed in those subjects for whom they were available. LBBB was significantly associated with the presence of SF and AR; within the LBBB group, 79 % had SF and 65 % had AR. Delayed AVO_ED, AVO_PVO, and delayed LV free-wall contraction were significantly associated with LBBB. AVO_ED and AVO_PVO positively correlated with QRS duration and negatively correlated with ejection fraction. Hearts with electrocardiographic evidence of LBBB showed lower septal-to-LV free-wall curvature ratios at end-diastole compared to normal controls. CMR can be used to identify and evaluate mechanical dyssynchrony in patients with LBBB. None of the normal controls showed the mechanical features associated with LBBB. Moreover, not all patients with LBBB showed the same degree of mechanical dyssynchrony, which could have implications for CRT.

Recent advances in echocardiography: strain and strain rate imaging

Deformation imaging by echocardiography is a well-established research tool which has been gaining interest from clinical cardiologists since the introduction of speckle tracking. Post-processing of echo images to analyze deformation has become readily available at the fingertips of the user. New parameters such as global longitudinal strain have been shown to provide added diagnostic value, and ongoing efforts of the imaging societies and industry aimed at harmonizing methods will improve the technique further. This review focuses on recent advances in the field of echocardiographic strain and strain rate imaging, and provides an overview on its current and potential future clinical applications.

Mechanical dyssynchrony and deformation imaging in patients with functional mitral regurgitation

Chronic functional mitral regurgitation (FMR) is a frequent finding of ischemic heart disease and dilated cardiomyopathy (DCM), associated with unfavourable prognosis. Several pathophysiologic mechanisms are involved in FMR, such as annular dilatation and dysfunction, left ventricle (LV) remodeling, dysfunction and dyssynchrony, papillary muscles displacement and dyssynchrony. The best therapeutic choice for FMR is still debated. When optimal medical treatment has already been set, a further option for cardiac resynchronization therapy (CRT) and/or surgical correction should be considered. CRT is able to contrast most of the pathophysiologic determinants of FMR by minimizing LV dyssynchrony through different mechanisms: Increasing closing forces, reducing tethering forces, reshaping annular geometry and function, correcting diastolic MR. Deformation imaging in terms of two-dimensional speckle tracking has been validated for LV dyssynchrony assessment. Radial speckle tracking and three-dimensional strain analysis appear to be the best methods to quantify intraventricular delay and to predict CRT-responders. Speckle-tracking echocardiography in patients with mitral valve regurgitation has been usually proposed for the assessment of LV and left atrial function. However it has also revealed a fundamental role of intraventricular dyssynchrony in determining FMR especially in DCM, rather than in ischemic cardiomyopathy in which MR severity seems to be more related to mitral valve deformation indexes. Furthermore speckle tracking allows the assessment of papillary muscle dyssynchrony. Therefore this technique can help to identify optimal candidates to CRT that will probably demonstrate a reduction in FMR degree and thus will experience a better outcome.

Association of apical rocking with long-term major adverse cardiac events in patients undergoing cardiac resynchronization therapy

AIMS

Correctly identifying patients who will benefit from cardiac resynchronization therapy (CRT) is still challenging. 'Apical rocking' is observed in asynchronously contracting ventricles and is associated with echocardiographic response to CRT. The association of apical rocking and long-term clinical outcome is however unknown at present. We assessed the predictive value of left ventricular (LV) apical rocking on a long-term clinical outcome in patients treated with CRT.

METHODS AND RESULTS

Consecutive heart failure patients treated with primary indication for CRT-D between 2005 and 2009 were included in a prospective registry. Echocardiography was performed prior to CRT to assess apical rocking, defined as motion of the LV apical myocardium perpendicular to the LV long axis. Major adverse cardiac event (MACE) was defined as combined end point of cardiac death and/or heart failure hospitalization and/or appropriate therapy (ATP and/or ICD shocks). All echocardiograms were assessed by independent cardiologists, blinded for clinical data. Multivariable analyses were performed to adjust for potential confounders. Two hundred and ninety-five patients with echocardiography prior to implantation were included in the final analyses. Apical rocking was present in 45% of the study patients. Apical rocking was significantly more common in younger patients, females, patients with sinus rhythm, non-ischaemic cardiomyopathy, and in patients with LBBB and wider QRS duration. During a mean clinical follow-up of 5.2 ± 1.6 years, 92 (31%) patients reached the end point of the study (MACE). Patients with MACE had shorter QRS duration, had more ischaemic cardiomyopathy, and were more often on Amiodarone. In univariate analyses, MACE was associated with shorter QRS duration, ischaemic aetiology, and the absence of apical rocking. After multivariable analyses, apical rocking was associated with less MACE (hazards ratio, HR 0.44, 95% confidence interval, CI 0.25-0.77).

CONCLUSION

Apical rocking is an independent predictor of a favourable long-term outcome in CRT-D patients.

Echocardiography and cardiac resynchronisation therapy, friends or foes?

Echocardiography is used in cardiac resynchronisation therapy (CRT) to assess cardiac function, and in particular left ventricular (LV) volumetric status, and prediction of response. Despite its widespread applicability, LV volumes determined by echocardiography have inherent measurement errors, interobserver and intraobserver variability, and discrepancies with the gold standard magnetic resonance imaging. Echocardiographic predictors of CRT response are based on mechanical dyssynchrony. However, parameters are mainly tested in single-centre studies or lack feasibility. Speckle tracking echocardiography can guide LV lead placement, improving volumetric response and clinical outcome by guiding lead positioning towards the latest contracting segment. Results on optimisation of CRT device settings using echocardiographic indices have so far been rather disappointing, as results suffer from noise. Defining response by echocardiography seems valid, although re-assessment after 6 months is advisable, as patients can show both continuous improvement as well as deterioration after the initial response. Three-dimensional echocardiography is interesting for future implications, as it can determine volume, dyssynchrony and viability in a single recording, although image quality needs to be adequate. Deformation patterns from the septum and the derived parameters are promising, although validation in a multicentre trial is required. We conclude that echocardiography has a pivotal role in CRT, although clinicians should know its shortcomings.

Association of apical rocking with super-response to cardiac resynchronisation therapy

Background

Super-responders to cardiac resynchronisation therapy (CRT) show an exceptional improvement in left ventricular ejection fraction (LVEF). Previous studies showed that apical rocking was independently associated with echocardiographic response to CRT. However, little is known about the association between apical rocking and super-response to CRT.

Objectives

To determine the independent association of LV apical rocking with super-response to CRT in a large cohort.

Methods

A cohort of 297 consecutive heart failure patients treated with primary indication for CRT-D were included in an observational registry. Apical rocking was defined as motion of the left ventricular (LV) apical myocardium perpendicular to the LV long axis. ‘Super-response’ was defined by the top quartile of LVEF response based on change from baseline to follow-up echocardiogram. Best-subset regression analysis identified predictors of LVEF super-response to CRT.

Results

Apical rocking was present in 45 % of patients. Super-responders had an absolute mean LVEF increase of 27 % (LVEF 22.0 % ± 5.7 at baseline and 49.0 % ± 7.5 at follow-up). Apical rocking was significantly more common in super-responders compared with non-super-responders (76 and 34 %, P < 0.001). In univariate analysis, female gender (OR 2.39, 95 % CI 1.38–4.11), lower LVEF at baseline (OR 0.91 95 % CI 0.87–0.95), non-ischaemic aetiology (OR 4.15, 95 % CI 2.33–7.39) and apical rocking (OR 6.19, 95 % CI 3.40–11.25) were associated with super-response. In multivariate analysis, apical rocking was still strongly associated with super-response (OR 5.82, 95 % CI 2.68–12.61). Super-responders showed an excellent clinical prognosis with a very low incidence of heart failure admission, cardiac mortality and appropriate ICD therapy.

Conclusion

Apical rocking is independently associated with super-response to CRT.

Electronic supplementary material

The online version of this article (doi:10.1007/s12471-015-0768-4) contains supplementary material, which is available to authorized users.

Newer Echocardiographic Techniques in Cardiac Resynchronization Therapy

Echocardiographic imaging plays a major role in patient selection for cardiac resynchronization therapy (CRT). One-third of patients do not respond; there is interest in advanced echocardiographic imaging to improve response. Current guidelines favor CRT for patients with electrocardiographic (ECG) QRS width of 150 milliseconds or greater and left bundle branch block. ECG criteria are imperfect; there is interest in advanced echocardiographic imaging to improve patient selection. This discussion focuses on newer echocardiographic methods to improve patient selection, improve delivery, and identify patients at risk for poor outcomes and serious ventricular arrhythmias.

Pericardiectomy is Associated with Improvement in Longitudinal Displacement of Left Ventricular Free Wall Due to Increased Counterclockwise Septal-to-Lateral Rotational Displacement

BACKGROUND

Pericardiectomy is an effective intervention for constrictive pericarditis. Speckle-tracking echocardiography can provide quantitative information not only about longitudinal strain (LS) but about longitudinal displacement (LD) and septal-to-lateral rotational displacement (SLRD). The aim of this study was to investigate whether pericardiectomy improves myocardial mechanics using speckle-tracking analysis.

METHODS

Eighty-three patients with constrictive pericarditis who underwent echocardiography were retrospectively assessed (mean age, 58 ± 12 years; 72 men; 50 idiopathic, 20 postoperative, four viral, three radiation, and six others) and compared with 20 healthy volunteers. LD and SLRD were measured from the apical four-chamber view and global LS from three apical views.

RESULTS

LD was less in the constrictive pericarditis group compared with control subjects (P < .001). Only lateral LS was significantly less than that of control subjects (P < .001), but septal LS was similar (P = .48). In pre- and post-pericardial surgery comparisons (n = 27), values of septal and lateral LD were almost identical (mean, 13.6 ± 4.7 vs 13.3 ± 5.4 mm; P = .70) before pericardiectomy, but septal LD decreased (mean, 9.3 ± 3.5 mm; P < .001) and lateral LD increased (mean, 16.8 ± 4.7 mm; P = .0106) after the surgery, even though the difference in LS between the septal and lateral walls decreased (from 5.6 ± 5.3% to 2.5 ± 4.2%, P = .008). Systolic whole-heart swinging motion significantly increased to a counterclockwise direction after surgery (mean SLRD, -0.8 ± 3.3° vs 2.1 ± 3.0°; P = .001). Although the change in SLRD after pericardiectomy was not different between patients with decreases and increases in New York Heart Association class, SLRD change was significantly greater in patients who received fewer diuretics after surgery (mean, 4.00 ± 0.91 vs 0.27 ± 1.47; P = .027).

CONCLUSIONS

After surgical removal of the pericardium, LD of the septal and lateral walls became significantly different, and counterclockwise SLRD increased, reflecting loss of pericardial support.