Dyssynchrony In Patients Research Articles

Association between an Early Revascularization Strategy and Major Cardiac Events Based on Left Ventricular Dyssynchrony in Patients at Intermediate Risk of Major Cardiac Events Using the J-ACCESS Risk Model.

Objective This retrospective study aimed to investigate the association between therapeutic strategies and the development of major cardiac events (MCEs) in intermediate-risk patients by using the the Japanese Assessment of Cardiac Events and Survival Study by Quantitative Gated SPECT (JACCESS) risk model in combination with the stress phase bandwidth (SPBW), an index of left ventricular dyssynchrony. Methods Patients were followed-up for three years to confirm their prognosis. Based on the estimated propensity scores, the patients who underwent revascularization within the first 60 days after SPECT and those who did not were matched 1:1 (n=367 per group). The composite endpoint was the occurrence of MCEs, consisting of cardiac death, non-fatal myocardial infarction, and severe heart failure. SPBW was calculated by a phase analysis using the Heart Risk View-F software program, and the MCE rate was compared between the two groups by applying the normal value of SPBW (38°). Patients The study included 2,053 patients with either known or suspected coronary artery disease who underwent electrocardiogram-gated single-photon emission computed tomography myocardial perfusion imaging and were at intermediate risk of MCE according to the J-ACCESS risk model. Results During follow-up, 54 of the 734 patients (7.4%) experienced MCEs. The overall incidence of MCE in intermediate-risk patients was not significantly different between the two groups. However, the incidence of MCE in patients with an abnormal SPBW was significantly lower in those who underwent early revascularization (4.8% vs. 11.9%, p=0.0407). Conclusion The combination of the J-ACCESS risk model and the SPBW is thus considered to be an optimal treatment strategy for patients at intermediate risk of MCE, and early revascularization may lead to an improved prognosis in intermediate-risk patients with an abnormal SPBW.

Mechanical dyssynchrony in patients with chronic heart failure and left bundle branch block

Background. The main problem in patient selection for cardiac resynchronization therapy (CRT) is the lack of unified approaches to the definition of mechanical dyssynchrony (MD) and selection criteria, particularly, in patients with left bundle branch block (LBBB).Aim: To study mechanical dyssynchrony indices and three-dimensional Echo (3DE) criteria of global and local contractility function in patients with chronic heart failure (CHF) and LBBB during different types of isolated left ventricle (LV) pacing.Methodology and Research Methods. The experimental intraoperative study involved 88 points obtained from 12 patients with CRT class IA indications and LBBB. During isolated LV pacing as part of CRT implantation procedure endocardial and epicardial pacing were obtained. Transesophageal Echo (TEE) cineloops recording and paced QRS complex morphology registrations by means of LabSystem Pro Electrophysiological Recording System (Bard Electrophysiology, USA) were performed during each stimulation episode. Philips Qlab 10 software was used for TEE data analysis.Results. The global (3D EF, 23.8 [22; 28.4], GLS, –5.33% [10.90%; –15.4%]) and local contractility (ExсAvg 3.5 [2.1; 5.6]) criteria and dyssyncrony indices (SDI-16, 14.9 [8.9; 23.1]) showed severe systolic dysfunction and intraventricular dyssynchrony – typical signs in this patient group, and differed significantly (3D EF, p = 0.003; GLS, p = 0.004; ExcAvg, p < 0.001; Tmsv-6 SD, р = 0.03) depending on the stimulation method and site. A moderate direct correlation between SDI-16 and the QRS duration (common electical dyssynchrony criterium) and inverse correlation with ExcAvg and 3D LVEF also describes LV response.

Sphingolipid Metabolism Is Associated with Cardiac Dyssynchrony in Patients with Acute Myocardial Infarction.

Sphingolipids are a class of complex and bioactive lipids that are involved in the pathological processes of cardiovascular disease. Fabry disease is an X-linked storage disorder that results in the pathological accumulation of glycosphingolipids in body fluids and the heart. Cardiac dyssynchrony is observed in patients with Fabry disease and left ventricular (LV) hypertrophy. However, little information is available on the relationship between plasma sphingolipid metabolites and LV remodelling after acute myocardial infarction (AMI). The purpose of this study was to assess whether the baseline plasma sphingomyelin/acid ceramidase (aCD) ratio predicts LV dyssynchrony at 6M after AMI. A total of 62 patients with AMI undergoing primary angioplasty were recruited. Plasma aCD and sphingomyelin were measured prior to primary angioplasty. Three-dimensional echocardiographic measurements of the systolic dyssynchrony index (SDI) were performed at baseline and 6 months of follow-up. The patients were divided into three groups according to the level of aCD and sphingomyelin above or below the median. Group 1 denotes lower aCD and lower sphingomyelin; Group 3 denotes higher aCD and higher sphingomyelin. Group 2 represents different categories of patients with aCD and sphingomyelin. Trend analysis showed a significant increase in the SDI from Group 1 to Group 3. Logistic regression analysis showed that the sphingomyelin/aCD ratio was a significant predictor of a worsening SDI at 6 months. AMI patients with high baseline plasma sphingomyelin/aCD ratios had a significantly increased SDI at six months. The sphingomyelin/aCD ratio can be considered as a surrogate marker of plasma ceramide load or inefficient ceramide metabolism. Plasma sphingolipid pathway metabolism may be a new biomarker for therapeutic intervention to prevent adverse remodelling after MI.

Вплив реваскуляризації коронарних артерій на механічну дисинхронію міокарду лівого шлуночка у хворих з коронарною хворобою серця

Introduction. Defining a treatment strategy for patients with stable coronary heart disease will require the development of personalized criteria, among which the assessment of myocardial dyssynchrony is considered promising. The aim of the study was to evaluate the effect of revascularization of coronary arteries on indicators of mechanical myocardial dyssynchrony in patients with stable coronary heart disease. Materials and methods. The study included 121 patients with coronary heart disease, who were assessed for mechanical myocardial dyssynchrony before and 2 weeks after revascularization. The main group included 48 patients with myocardial dyssynchrony, and the comparison group included 73 patients without myocardial dyssynchrony. Complete occlusion and lesions of 3 coronary arteries were found more often in the group with myocardial dyssynchrony, and the main group also had a higher SYNTAX SCORE. The results. Mechanical dyssynchrony of the myocardium was found in 39% of patients with coronary heart disease. Before revascularization, a signifiant increase in SPWMD, APEI, IVMD, and a decrease in LVFT and LVET were found in the group of patients with myocardial dyssynchrony. After revascularization in the main group, in 9 patients out of 48 (18.7%), indicators of myocardial dyssynchrony returned to normal values. LVFT in the group of patients with myocardial dyssynchrony significantly increased, as well as left ventricular ejection time (LVET) (from 318.5±9.6 ms to 344.9±23.2 ms, p<0.01). Conclusions. After revascularization, the number of patients with myocardial dyssynchrony significantly decreased due to the improvement of interventricular and intraventricular dyssynchrony indicators. Key words: myocardial dyssynchrony, coronary heart disease, revascularization, coronary angiography, SYNTAX SCORE.

Correlates of markers of dyssynchrony in patients with STEMI and multivessel disease: an analysis from the IAEA SPECT STEMI trial.

In this substudy of the Value of Gated-SPECT MPI for Ischemia- Guided PCI of non-culprit vessels in STEMI Patients with Multi vessel Disease after primary PCI trial after primary PCI we aim to assess if infarct size affects conventional measures of dyssynchrony at rest. Additionally, we explore if there is an independent correlation of stress-inducible ischemia with dyssynchrony at rest. The 48 patients with imaging at randomization were analyzed. Gated-single-photon emission computed tomography (SPECT) MPI with vasodilator stress and technetium-99m-labeled tracers was performed. The phase histogram bandwidth (HBW), phase SD, and entropy were obtained with the QGS software. Correlation between dyssynchrony at rest and infarct size and inducible ischemia was performed using the Spearman test. According to normal database limits dyssynchrony parameters at rest were abnormal for men. In women only HBW was abnormal. Correlation between the summed rest score with dyssynchrony was significant only for entropy ( P = 0.035). No correlation was observed for dyssynchrony and stress-induced ischemia. Entropy, as a measure of dyssynchrony, has potential in the assessment of patients with STEMI and multivessel disease after primary PCI. Smaller residual myocardial scars in PCI-reperfused patients with STEMI may contribute to the lack of correlation between dyssynchrony at rest and infarct size and stress-induced ischemia, respectively.

Relationship between left ventricular mechanical dyssynchrony and accelerated 99mTc-MIBI clearance in patients with heart failure

Aim. To evaluate 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) washout rate and its relationship with contractility and left ventricular (LV) mechanical dyssynchrony in patients with heart failure (HF) of non-ischemic origin.Material and methods. The study included 20 patients with HF of non-ischemic origin with indications for cardiac resynchronization therapy (CRT). Ten patients without HF were included in the comparison group. All patients underwent 99mTc-MIBI myocardial perfusion scintigraphy (MPS). We assessed the 99mTc-MIBI washout rate, as well as LV perfusion, contractility, and mechanical dyssynchrony using phase analysis data (phase standard deviation, histogram bandwidth (HBW), asymmetry, and gradient). Six months after CRT, all patients with HF underwent MPS to assess the changes of studied parameters.Results. According to MPS, patients with HF had a higher 99mTc-MIBI washout rate from the LV myocardium compared with the comparison group (10,9 (8,49-13,8) vs 3,98 (0,9-9,8)%, p=0,0001), as well as severe LV mechanical dyssynchrony (standard deviation: 66 (55,11-73,24) vs 13,1 (10,1-19,6), p<0,0001; HBW: 207 (165-246) vs 40 (33-66), p<0,0001). The 99mTc-MIBI washout rate was positively correlated with LV end-diastolic (r=0,46, p<0,001) and LV end-systolic volumes (r=0,44, p<0,001) and negatively correlated with LV ejection fraction (r=0,41, p<0,001). A moderate correlation was found between the 99mTc-MIBI washout rate and following LV mechanical dyssynchrony and contractility parameters: HBW (r=0,412, p<0,001), asymmetry (r=-0,41, p<0,001), gradient (r=-0,44, p<0,001), wall motion (r=-0,45, p=0,001), wall thickening (r=-0,54, p<0,001). Six months after CRT, all patients showed a significant decrease in the 99mTc-MIBI washout rate from 12,4 (10,3-14,9) to 8,14 (3,37-8,88)%, p=0,0006.Conclusion. In patients with HF of non-ischemic origin, an increase in the 99mTc-MIBI washout rate from the LV myocardium is associated with the severity of impaired cardiac contractility and mechanical dyssynchrony.

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.

Abstract 13141: Max Opposing Wall Delay in Right Atrial Strain Can Be a Prognostic Factor at 30-day Mortality in Submassive Pulmonary Embolism

Background: Submassive pulmonary embolism (sPE) is common and associated with significant mortality. Right ventricular dyssynchrony caused by sPE were reported previously. However, limited studies have evaluated dyssynchrony of right atrium (RA) strain in the setting of sPE. The purpose of this study was to identify the potential role of RA dyssynchrony in patients with sPE. Methods: 201 patients with sPE were assessed in this retrospective cohort study. All echocardiograms were completed within 48 hours of diagnosis. RA strain was analyzed retroactively using TOMTEC®. RA dyssynchrony was defined as absolute max opposing wall delay which was time interval between peak lateral and septal wall strain in RA after R-R interval correction (maxOWD) (Figure 1). The primary outcome was 30-day all-cause mortality. Results: 201 patients included in the study. Mortality rate of 11.4% was seen at 30 days. Median maxOWD in survivors was significantly low compared to that in non-survivors (4.35 vs 16.20, p < 0.001). Univariable and Multivariable analysis showed maxOWD was an independent factor to predict short-term mortality. Receiver operating characteristics (ROC) analysis revealed area under the curve was 0.795 and best cutoff value was 10.43. Using the cutoff value, Kaplan-Meier curves depicted survival rate in patients with maxOWD > 10.43 was significantly lower than those with maxOWD ≤ 10.43. (Hazard Ratio 7.84, p < 0.001) (Figure 2) Conclusions: Max opposing wall delay after R-R interval correction in RA strain has significant prognostic value in assessing risk of mortality in patients with submassive PE.

Changes in the biomechanics of contractility of the myocardium of the left ventricle: results of prospective follow-up

As a result of a two-year prospective study, the differences between intraventricular and interventricular dyssynchrony in patients with arterial hypertension, atherosclerotic and postinfarction cardiosclerosis were determined according to the data of echocardiography in the standard mode and in the mode of tissue myocardial dopplerography.

Real-time three dimensional tte in quantification of left ventricular dyssynchrony

Background. The main problem in the patient selection for cardiac resynchronization therapy (CRT) is the lack of unified approaches to the definition of mechanical dyssynchrony (MD) and selection criteria.Objective. To reveal the dependence of the criteria of dyssynchrony in patients on the method and point of stimulation and to reveal the correlation of these data with the width of the QRS complex and the percentage of global two-dimensional longitudinal deformation.Design and methods. The study involved 12 patients with drug-compensated CHF of class II-IV, LVEF< 35 % and a QRS duration >130 ms, having CRT indications. All patients were intraoperatively injected with a retrograde transaortically guided electrode. During stimulation of each point (88 points), transesophageal Echo-KG (PE Echo-KG) was performed. TomTec and Philips Qlab 3DQ Advanced software was used for data analysis.Results. The segmental excursion and myocardial contractility differed significantly depending on the stimulation point. A moderate inverse correlation was found between ExcAvg, LVEF and QRS duration. There were a direct correlation of the SDI-16 and the QRS duration was shown, and an inverse correlation of SDI-16 with ExcAvg and LVEF. 2D longitudinal global strain was inversely correlated with the EF.Conclusion. The technique is useful for regional LV myocardial contractility assessment and patient selection and comparison of alternative approaches to LV pacing to improve response to CRT.

Left ventricular pacing in the treatment of pediatric cardiac dysfunction caused by idiopathic complete left bundle branch block.

This study aimed to investigate the feasibility and effectiveness of transthoracic epicardial dual-chamber pacemaker implantation in the treatment of cardiac dysfunction caused by idiopathic complete left bundle branch block (CLBBB) in children. Nine children diagnosed with cardiac dysfunction due to idiopathic CLBBB were included in this study. All patients underwent transthoracic epicardial dual-chamber pacemaker implantation. Cardiac function was evaluated using echocardiography during the follow-up. Additionally, intraventricular synchronization parameters were assessed using two-dimensional speckle tracking echocardiography (STE). Nine children (mean age, 3.0±2.6 years) were included in this study. The median follow-up duration was 2 (interquartile range, 1-3) years. The cardiac function of all patients recovered to normal levels within 1 year postoperatively. The postoperative QRS duration on electrocardiography (142±21ms) was significantly shorter than that at baseline (106±12ms) (p<.05). Cardiac dyssynchrony in patients who manifested preoperatively achieved complete correction after pacemaker implantation. The comparison of preoperative and postoperative (last follow-up visit) synchronization parameters were as follows: longitudinal standard deviation of the time to peak strain, 99.0±41.9 versus 36.8±5.0ms (p=.004); delay time of peak longitudinal strain, 252.2±131.4 versus 35.0±22.9ms (p=.002); and longitudinal systolic dyssynchrony index, 2.8±0.8% versus 1.0±0.3% (p=.001), respectively. Transthoracic epicardial dual-chamber pacemaker implantation (with left atrial sensing and left ventricular single-site pacing) can be used for the treatment of cardiac dysfunction caused by idiopathic CLBBB in children.

Atrioventricular dyssynchrony in patients with permanent pacemaker due to sinus node dysfunction and first-degree atrioventricular block: does the long PR syndrome exist?

Atrioventricular dyssynchrony in patients with permanent pacemaker due to sinus node dysfunction and first-degree atrioventricular block: does the long PR syndrome exist?

Оцінка механічної диссинхронії міокарду у хворих з різними формами коронарної хвороби серця, яким проводилась реваскуляризація

The purpose of the study was to determine the presence of mechanical dyssynchrony of the myocardium in patients with various clinical variants of coronary heart disease undergoing revascularization. Materials and methods. 137 patients (106 men and 31 women, aged from 31 to 81 years) took part in the study, including 121 patients with coronary heart disease who underwent a revascularization procedure. Results and discussion. The frequency of detection of mechanical dyssynchrony of the myocardium is significantly higher in patients with coronary heart disease compared to patients without coronary heart disease who underwent revascularization (41.3% vs. 6.2%, respectively). Aortic transit time was significantly and significantly greater in the group of patients with coronary heart disease compared to patients without coronary heart disease, while pulmonary transit time was the same in the comparison groups. Accordingly, this caused a significant difference in interventricular mechanical delay. Left ventricular filling time was significantly shorter in the group of patients with coronary heart disease and, conversely, left ventricular ejection time was shorter in the group of patients without coronary heart disease. The study showed a significant increase in the frequency of myocardial dyssynchrony in patients with coronary heart disease who underwent revascularization, which creates conditions for studying the prognostic value in relation to the clinical results of revascularization. The time of advancement to the aorta was significantly and reliably longer in the group of patients with coronary heart disease compared to patients without coronary heart disease, while the time of advancement to the pulmonary artery was the same in the comparison groups, which caused a significant difference in the interventricular mechanical delay and confirms dependence of the development of myocardial dyssynchrony on the localization of the coronary artery lesion. Conclusion. Indicators of diastolic dysfunction of the left ventricular myocardium, although there was a tendency for a difference between the group of patients with coronary heart disease and the comparison group, this tendency was unreliable, which demonstrated their later change in relation to the indicators of myocardial dyssynchrony. The data obtained by us confirm the greater informativeness of mechanical dyssynchrony of the left ventricle indicators in comparison with indicators that characterize diastolic function and their earlier changes in patients with coronary heart disease. In turn, early detection and treatment of mechanical dyssynchrony of the left ventricle can delay the onset of left ventricular dysfunction in patients with coronary heart disease

Abstract 10515: Mechanical Dyssynchrony in Patients With a Fontan Circulation and Its Relationship to Outcomes

Introduction: The prevalence and significance of mechanical dyssynchrony is not well known in the Fontan population. Methods: Single-center, retrospective analysis of CMRs in Fontan patients compared to healthy controls. Feature tracking was performed on all slices of a short-axis cine stack and dyssynchrony index (DI) was defined as the standard deviation of time-to-peak circumferential strain for all segments. A composite outcome was defined as death, heart transplant listing, or new ventricular arrhythmias. Results: A total of 512 cases (17±9 y) and 42 controls (16±9 y) were included. Figure 1 depicts differences in EDV i , EF, DI, and QRS duration between the cohorts. DI correlated with EDV i (r=0.35; p&lt;0.01), EF (r=-0.29; p&lt;0.01), and QRS duration (r=0.29; p&lt;0.01). At a median follow-up of 4.2 yrs, 10% had death or transplant listing and 4% had ventricular arrhythmias. RV dominance, EDV i , EF, DI, and QRS interval were associated with increased risk of the composite outcome (Table 1). Figure 2 demonstrates a significantly higher probability of the composite outcome in those with EDV i &gt;120 ml/m 2 and DI&gt;70 ms. Conclusion: Fontan patients have more mechanical dyssynchrony and longer QRS duration compared to controls. These abnormalities are more pronounced in RV or mixed ventricular morphology and are associated with a higher risk of ventricular arrhythmias, transplant listing, or death.

Neurometabolism and Ventricular Dyssynchrony in Patients With Heart Failure and Reduced Ejection Fraction

BackgroundThe brain coordinates the heart through the autonomic nervous system (ANS). Numerous mediator signals along the brain-heart axis interact with the neuronal-metabolic system in heart failure (HF). Disturbances in cardio-neural interactions influence the disease progression in patients with HF. ObjectivesThe purpose of this study was to investigate the interactome between ANS-associated neurometabolism and ventricular dyssynchrony in patients with heart failure with reduced ejection fraction (HFrEF). Further, we studied the association of neurometabolism with major arrhythmic events (MAEs). MethodsA total of 197 patients with HFrEF who underwent gated single-photon emission computed tomography myocardial perfusion imaging and the brain 18F-fluorodeoxyglucose positron emission tomography/computed tomography were prospectively enrolled. Relationships between the brain metabolism and MAEs were assessed using Cox models and mediation analyses. Finally, metabolic central autonomic networks were constructed and statistically compared between patients with and without MAEs. ResultsIn total, 35 (17.8%) patients experienced MAEs during a median follow-up of 3.1 years. In patients with HFrEF (age 58 years [IQR: 50-64 years], left ventricular ejection fraction: 20.0% [IQR: 15.0%-25.0%]), glucose hypometabolism in the insula, hippocampus, amygdala, cingulate gyrus, and caudate nucleus were independent predictors for MAEs (all P < 0.05). Cerebral hypometabolism was related to ventricular dyssynchrony, which was the predominant risk factor of MAEs. Additionally, patients who experienced MAEs presented hypoconnectivity in the metabolic central autonomic network compared with those without MAEs (P < 0.05). ConclusionsWe found an interaction of the neuronal metabolic-ventricular dyssynchronization axis in HF, which might be related to MAEs. This new brain-heart axis could expand our understanding of the distinct pathomechanisms of HFrEF.

Global left ventricular myocardial work efficiency in left bundle branch pacing versus right ventricular septal pacing: preliminary results of a randomized trial

Abstract Background Recently, the concept of left bundle branch pacing (LBBP) has emerged in clinical practice, in an attempt to prevent the deteriorating effects of right ventricular pacing (Vp). Purpose The aim of this study is to compare the effect of Vp on left ventricular (LV) dyssynchrony in patients with atrioventricular block (AVB) and preserved ejection fraction (EF), subjected to either LBBP or right ventricular septal pacing (RVSP). Methods Patients with AVB are randomized 1:1 to LBBP or RVSP. The effect of Vp is evaluated by echocardiographic indices of dyssynchrony, such as global myocardial work efficiency (GWE) and peak systolic dispersion (PSD). GWE represents the ratio of constructive work divided by the sum of constructive and wasted work [1]. Successful LBBP is defined by the presence of right bundle branch block paced QRS morphology in lead V1 and stim to LV activation time &amp;lt;75 msec [2]. No back-up right Vp lead was used in LBBP group. Results We conducted a preliminary analysis of the first 20 patients. Enrollment is still ongoing and total follow-up period is one year. We sought to investigate the acute effect of Vp on LV dyssynchrony 24 hours post procedure. Patients' baseline characteristics were similar in both groups and are presented in Table 1. One crossover was noted from LBBP to RVSP group, due to high ventricular capture threshold during implant. Implantation time was increased in LBBP arm (130±17.4 min in LBBP versus 47.7±4.5 min in RVSP group, p=0.004). Left bundle branch potential was recorded in 3 out of 10 LBBP patients. No statistically significant difference was demonstrated in GWE between the two groups (91.3% in LBBP versus 87.4% in RVSP group, p=0.052). PSD was numerically shorter in LBBP (53.3 msec) versus in RVSP (63.6 msec), p=0.114. There were no complications during both the acute perioperative phase and the running period of the follow-up. Moreover, no acute ventricular threshold capture rise, or lead dislodgement has been observed in neither group. The increased implantation time may be attributed to the more demanding technique, or the learning curve period required in the arm of LBBP. In the present analysis, a remarkable difference regarding GWE in favor of the LBBP group was demonstrated, although statistically not significant. However, even in this initial phase of the study, there is a trend of better LV synchrony and less wasted myocardial work in the LBBP group. The final difference of these indices will be assessed at the end of the one-year follow-up, when comparative results will be available. Conclusion LBBP is a novel, safe pacing method. Despite the longer procedural time and the risk of crossover, LBBP seems to offer better – without however statistical significance – LV synchrony even in the acute postoperative phase compared to RVSP. Longer follow-up studies are required to test whether LBBP compared to RVSP confers substantial clinical benefit. Funding Acknowledgement Type of funding sources: None.

Correlation of left ventricular mechanical dyssynchrony in patients with chronic kidney disease using phase analysis of gated single photon emission computed tomography myocardial perfusion imaging

Abstract Background Left ventricular mechanical dyssynchrony (LVMD) possesses deleterious effects that have been neglected in chronic kidney disease (CKD) as a cause of left ventricular dysfunction and further progression to heart failure, possibly contributing to sudden cardiac death in this population. Thus, cardiovascular risk assessment is essential in early stages of CKD as well as in the pre-transplant screening and this can be performed non-invasively by modalities including phase analysis Gated-SPECT myocardial perfusion imaging (MPI). This modality has emerged as a prognostic tool to predict mortality independent of MPI abnormalities as well as assessment of ventricular synchrony. Purpose The goal of this study is to evaluate the relationship of left ventricular mechanical dyssynchrony using phase analysis G-SPECT and chronic kidney disease severity and its predictors. Methods We included 567 patients who underwent one day rest/stress (dipyridamole) 99mTc-sestamibi myocardial perfusion imaging with G-SPECT for the following indications for testing: detection of CAD among asymptomatic patients, risk assessment during pre-operative evaluation for kidney transplantation and evaluation for noncardiac surgery without active cardiac conditions between January 2017 to January 2021. Data was collected including gender, age, risk factors resting heart rate and baseline blood pressure. Gated SPECT-MPI was performed according to the protocol rest followed by stress images (dipyridamole) 99mTc-sestamibi. The rest and stress phase analysis (histogram bandwidth, standard deviation of phase and entropy) parameters were compared between the five stages of chronic kidney disease. Data of the stress-rest difference in dyssynchrony was analyzed using McNemar's test; crude odds ratios and adjusted odds or multivariate analysis were done. Results Advanced CKD (Stage 4–5) shows statistically significant correlation with the Histogram bandwidth (HBW) both at stress (p=0.008) and rest (p=0.018), and stress entropy (p=0.007). As for the other stages, LVMD is present with similar results seen with the phase parameters HBW and PSD, the entropy values at rest than at stress for Stages I to IV (p&amp;lt;0.05). On further analysis, abnormal perfusion showed to be an independent predictor of left ventricular mechanical dyssynchrony across all arms. Other associated factors includes advanced CKD (stages 4–5), male sex, BMI ≥30 kg/m2, blood pressure and resting heart rate were significantly associated with increased odds of dyssynchrony across stress and rest tests. Overall, the full models were statistically significant, with R-squared ranging from 14.96% to 30.11% (p&amp;lt;0.001). Conclusion This study showed that CKD patients have left ventricular mechanical dyssynchrony on gated-SPECT MPI. Hence, it can be used as an alternative for early assessment and guide decision making for the treatment of patients with CKD to prevent further cardiovascular complication. Funding Acknowledgement Type of funding sources: None.

Assessment of electrical dyssynchrony in cardiac resynchronization therapy: 12-lead electrocardiogram vs. 96-lead body surface map.

The standard deviation of activation time (SDAT) derived from body surface maps (BSMs) has been proposed as an optimal measure of electrical dyssynchrony in patients with cardiac resynchronization therapy (CRT). The goal of this study was two-fold: (i) to compare the values of SDAT in individual CRT patients with reconstructed myocardial metrics of depolarization heterogeneity using an inverse solution algorithm and (ii) to compare SDAT calculated from 96-lead BSM with a clinically easily applicable 12-lead electrocardiogram (ECG). Cardiac resynchronization therapy patients with sinus rhythm and left bundle branch block at baseline (n = 19, 58% males, age 60 ± 11 years, New York Heart Association Classes II and III, QRS 167 ± 16) were studied using a 96-lead BSM. The activation time (AT) was automatically detected for each ECG lead, and SDAT was calculated using either 96 leads or standard 12 leads. Standard deviation of activation time was assessed in sinus rhythm and during six different pacing modes, including atrial pacing, sequential left or right ventricular, and biventricular pacing. Changes in SDAT calculated both from BSM and from 12-lead ECG corresponded to changes in reconstructed myocardial ATs. A high degree of reliability was found between SDAT values obtained from 12-lead ECG and BSM for different pacing modes, and the intraclass correlation coefficient varied between 0.78 and 0.96 (P < 0.001). Standard deviation of activation time measurement from BSM correlated with reconstructed myocardial ATs, supporting its utility in the assessment of electrical dyssynchrony in CRT. Importantly, 12-lead ECG provided similar information as BSM. Further prospective studies are necessary to verify the clinical utility of SDAT from 12-lead ECG in larger patient cohorts, including those with ischaemic cardiomyopathy.

Prognostic risk stratification based on left ventricular mechanical dyssynchrony in patients at low or intermediate risk of major cardiac events using the J-ACCESS risk model.

There have been no reports on prognostic prediction and risk stratification based on stress phase bandwidth (SPBW), or a left ventricular (LV) mechanical dyssynchrony index, in patients with known or suspected stable coronary artery disease (CAD) at low or intermediate risk of major cardiac events (MCEs) using the J-ACCESS risk model. We retrospectively investigated 4,996 consecutive patients with known or suspected CAD who underwent rest 201Tl and stress 99mTc-tetrofosmin electrocardiogram (ECG)-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) and followed up for 3 years to confirm their prognosis. MCE risk over 3 years was estimated using an equation based on that used in the J-ACCESS study. The composite endpoint was the onset of MCEs consisting of cardiac death, non-fatal myocardial infarction (MI), and severe heart failure requiring hospitalization. SPBW was calculated by phase analysis with the Heart Risk View-F software and its normal upper limit was set to 38°. Based on the estimated 3-year incidence of MCEs obtained from the J-ACCESS risk model, 4,123 of the 4,996 consecutive patients were classified as low (n = 2,653) or intermediate risk (n = 1,470) and they were analyzed for follow-up. During the follow-up, 153 patients experienced MCEs: cardiac death (n = 38), non-fatal MI (n = 45), and severe heart failure (n = 70). The results of the multivariate analysis showed age, estimated glomerular filtration rate (eGFR), stress LV ejection fraction, and stress SPBW to be independent predictors of MCEs. The actual 3-year MCE rate in patients at intermediate risk was significantly higher than in those at low risk (6.7% vs. 2.1%, P < 0.0001). However, the actual 3-year MCE rate in patients with abnormal SPBW (> 38°) was 4.0% and 9.2% in low- and intermediate-risk patients, respectively, which corresponded to intermediate and high risk. Kaplan-Meier analysis also showed significant risk stratification by normal SPBW values for both low- and intermediate-risk patients. LV mechanical dyssynchrony assessed with ECG-gated SPECT MPI is useful for risk stratification of known or suspected stable CAD patients at low or intermediate risk of MCEs and may help identify higher risk patients who could not be identified as being at risk based on J-ACCESS risk assessment.

Prognostic value of ventricular mechanical dyssynchrony in patients with left ventricular aneurysm: A comparative study of medical and surgical treatment

BackgroundThe prognostic value of left ventricular (LV) mechanical dyssynchrony (MD) in patients with LV aneurysm (LVA) is unclear. This study aimed to investigate the long-term prognostic value of LVMD in LVA patients. Methods92 consecutive patients who underwent 99mTc-sestamibi-gated SPECT myocardial perfusion imaging (GSPECT) were retrospectively analyzed and followed-up for a median of 63 months (range, 1-73 months). LV function and histogram bandwidth (BW) were analyzed by QGS software. LVMD was defined by ROC analysis. Cardiac death was defined as the primary endpoint, and the composite of cardiac deaths and severe or acute heart failure (MACE) as the secondary endpoint. ResultsThe annual cardiac mortality rate of LVA patients with LVMD and treated by surgical therapy was significantly lower than those treated by medical therapy (2.40% vs. 6.40%, P < .05) but not annual MACE rate (6.61% vs. 10.06%, P > .05). In patients without LVMD, no significant difference in survival and MACE-free survival between medical and surgical treatment. In addition, the occurrence of LVMD is related to the worsen cardiac outcome in terms of MACE and cardiac death, independent of the treatment methods. BW was an independent predictor for MACE (HR 1.010, P < .01) and LVEF (HR .928, P < .05) was an independent predictor for cardiac death in all LVA patients. ConclusionsLVA patients with LVMD might be associated with high risk for cardiac death and surgical treatment might improve cardiac survival compared to medical therapy in these patients.