Atrial fibrillation-specific refinement of the STOP-Bang sleep apnoea screening questionnaire: insights from the Virtual-SAFARI study

BACKGROUND

Sleep-disordered breathing (SDB) is prevalent in up to 50% of patients referred for atrial fibrillation (AF) catheter ablation (CA). Currently, it remains unclear how to improve pre-selection for SDB screening in patients with AF.

AIM

We aimed to (1) assess the accuracy of the STOP-Bang screening questionnaire for detection of SDB within an AF population referred for CA; (2) derive a refined, AF-specific SDB score to improve pre-selection.

METHODS

Consecutive AF patients referred for CA without a history of SDB and/or SDB screening were included. Patients were digitally referred to the previously implemented Virtual-SAFARI SDB screening and management pathway including a home sleep test. An apnoea-hypopnoea index (AHI) of  ≥ 15 was interpreted as moderate-to-severe SDB. Logistic regression analysis was used to assess characteristics associated with moderate-to-severe SDB to refine pre-selection for SDB screening.

RESULTS

Of 206 included patients, 51% were diagnosed with moderate-to-severe SDB. The STOP-Bang questionnaire performed poorly in detecting SDB, with an area under the receiver operating characteristic curve (AUROC) of 0.647 (95% Confidence-Interval (CI) 0.573-0.721). AF-specific refinement resulted in the BOSS-GAP score. Therein, BMI with cut-off point ≥ 27 kg/m2 and previous stroke or transient ischaemic attack (TIA) were added, while tiredness and neck circumference were removed. The BOSS-GAP score performed better with an AUROC of 0.738 (95% CI 0.672-0.805) in the overall population.

CONCLUSION

AF-specific refinement of the STOP-Bang questionnaire moderately improved detection of SDB in AF patients referred for CA. Whether questionnaires bring benefits for pre-selection of SDB compared to structural screening in patients with AF requires further studies.

TRIAL REGISTRATION NUMBER

ISOLATION was registered NCT04342312, 13-04-2020.

360° Virtual reality to improve patient education and reduce anxiety towards atrial fibrillation ablation

AIMS

Evaluation of (i) the effects of a virtual reality (VR) preprocedural patient education video on information provision, procedure-related knowledge, satisfaction, and the level of worries in patients planned for atrial fibrillation (AF) ablation and (ii) the feasibility of a disposable cardboard VR viewer for home use in this setting.

METHODS AND RESULTS

In this prospective observational cohort study, patients were alternatively assigned in a 1:1 ratio to the control or VR group. Controls received standard preprocedural information. VR group received standard information and a VR video (via in-hospital VR headset and disposable cardboard). The Amsterdam Preoperative Anxiety and Information Scale (APAIS) together with additional questions concerning procedural experience and satisfaction was completed pre- and post-ablation. Of 134 patients [38.1% female, aged 66 (58-72) years] included, 49.2% were assigned to the control and 50.7% to the VR group. The number of patients that worried about the ablation procedure was lower in VR than in control patients (19.1% vs. 40.9%, P = 0.006). More VR females than males had worries about the procedure (34.8% vs. 11.1%, P = 0.026). The number of VR patients that were satisfied with the preprocedural information provision was higher post-ablation than pre-ablation (83.3% vs. 60.4%, P = 0.007). In total, 59.4% reported that the disposable cardboard was easy to use and led to a discussion with relatives in 68.8%.

CONCLUSION

In patients scheduled for AF ablation, a VR preprocedural educational video led to better information provision and procedure-related knowledge, higher satisfaction, and less worries regarding the procedure. The disposable cardboard was feasible for home use.

A new efficient and integrated pathway for patient evaluation prior to atrial fibrillation ablation

AIM

In this quality improvement project, a care pathway for patients considered for atrial fibrillation (AF) ablation was optimized with the goals to improve the patient journey and simultaneously integrate prospective data collection into the clinical process.

METHODS AND RESULTS

The Lean Six Sigma approach was used to map the pre-existing process, identify constraints and formulate countermeasures. The percentage of patients going through the full pre-ablation preparation that eventually underwent AF ablation, number of hospital visits and consultations, pathway compliance, and completeness of scientific data were measured before and after pathway optimisation. Constraints in the process were (1) lack of standardized processes, (2) inefficient use of resources, (3) lack of multidisciplinary integration, (4) lack of research integration, and (5) suboptimal communication. The impact of the corresponding countermeasures (defining a uniform process, incorporating 'go/no-go' moment, introducing a 'one-stop-shop', integrating prospective data collection, and improving communication) was studied for 33 patients before and 26 patients after pathway optimisation. After optimisation, the percentage of patients receiving a full pre-ablation preparation that eventually underwent AF ablation increased from 59% to 94% (p < 0.01). Fewer hospital visits (3.2 ± 1.2 versus 2.3 ± 0.8, p = 0.01) and electrophysiologist consultations (1.8 ± 0.7 versus 1.0 ± 0.3, p < 0.01) were required after pathway optimisation. Pathway compliance and complete collection of scientific data increased significantly (3% versus 73%, p < 0.01 and 15% versus 73%, p < 0.01, respectively).

CONCLUSION

The optimisation project resulted in a more efficient evaluation of patients considered for AF ablation. The new more efficient process includes prospective data collection and facilitates easy conduct of research studies focused on improvements of patient outcomes.

Mobile app-based symptom-rhythm correlation assessment in patients with persistent atrial fibrillation

BACKGROUND

The assessment of symptom-rhythm correlation (SRC) in patients with persistent atrial fibrillation (AF) is challenging. Therefore, we performed a novel mobile app-based approach to assess SRC in persistent AF.

METHODS

Consecutive persistent AF patients planned for electrical cardioversion (ECV) used a mobile app to record a 60-s photoplethysmogram (PPG) and report symptoms once daily and in case of symptoms for four weeks prior and three weeks after ECV. Within each patient, SRC was quantified by the SRC-index defined as the sum of symptomatic AF recordings and asymptomatic non-AF recordings divided by the sum of all recordings.

RESULTS

Of 88 patients (33% women, age 68 ± 9 years) included, 78% reported any symptoms during recordings. The overall SRC-index was 0.61 (0.44-0.79). The study population was divided into SRC-index tertiles: low (<0.47), medium (0.47-0.73) and high (≥0.73). Patients within the low (vs high) SRC-index tertile had more often heart failure and diabetes mellitus (both 24.1% vs 6.9%). Extrasystoles occurred in 19% of all symptomatic non-AF PPG recordings. Within each patient, PPG recordings with the highest (vs lowest) tertile of pulse rates conferred an increased risk for symptomatic AF recordings (odds ratio [OR] 1.26, 95% coincidence interval [CI] 1.04-1.52) and symptomatic non-AF recordings (OR 2.93, 95% CI 2.16-3.97). Pulse variability was not associated with reported symptoms.

CONCLUSIONS

In patients with persistent AF, SRC is relatively low. Pulse rate is the main determinant of reported symptoms. Further studies are required to verify whether integrating mobile app-based SRC assessment in current workflows can improve AF management.

Rationale and Design of the ISOLATION Study: A Multicenter Prospective Cohort Study Identifying Predictors for Successful Atrial Fibrillation Ablation in an Integrated Clinical Care and Research Pathway

Introduction

Continuous progress in atrial fibrillation (AF) ablation techniques has led to an increasing number of procedures with improved outcome. However, about 30-50% of patients still experience recurrences within 1 year after their ablation. Comprehensive translational research approaches integrated in clinical care pathways may improve our understanding of the complex pathophysiology of AF and improve patient selection for AF ablation.

Objectives

Within the "IntenSive mOlecular and eLectropathological chAracterization of patienTs undergoIng atrial fibrillatiOn ablatioN" (ISOLATION) study, we aim to identify predictors of successful AF ablation in the following domains: (1) clinical factors, (2) AF patterns, (3) anatomical characteristics, (4) electrophysiological characteristics, (5) circulating biomarkers, and (6) genetic background. Herein, the design of the ISOLATION study and the integration of all study procedures into a standardized pathway for patients undergoing AF ablation are described.

Methods

ISOLATION (NCT04342312) is a two-center prospective cohort study including 650 patients undergoing AF ablation. Clinical characteristics and routine clinical test results will be collected, as well as results from the following additional diagnostics: determination of body composition, pre-procedural rhythm monitoring, extended surface electrocardiogram, biomarker testing, genetic analysis, and questionnaires. A multimodality model including a combination of established predictors and novel techniques will be developed to predict ablation success.

Discussion

In this study, several domains will be examined to identify predictors of successful AF ablation. The results may be used to improve patient selection for invasive AF management and to tailor treatment decisions to individual patients.

Case report: ventricular fibrillation and cardiac arrest provoked by forward bending in adolescent with severe pectus excavatum

Background

Life-threatening arrhythmias have been reported in patients with severe pectus excavatum in absence of other cardiac abnormalities. Literature is scarce regarding diagnosis, cause and management of this problem, particularly regarding the question as to whether the placement of an implantable cardioverter-defibrillator (ICD) is necessary.

Case summary

A 19-year-old male patient with severe pectus excavatum was scheduled for elective surgical correction. During forward bending for epidural catheter placement, syncope and ventricular fibrillation (VF) occurred resulting in cardiac arrest. After successful cardiopulmonary resuscitation, extensive analysis was performed and showed no cause for VF other than cardiac compression (particularly of the left atrium, right atrium, and ventricle to a lesser degree) due to severe pectus excavatum. Postponed correction by modified Ravitch was performed without ICD placement, with an uneventful post-operative recovery. Eighteen months after surgery, the patient remains well. Upon specific request, he did remember dizzy spells when tying shoelaces. He always considered this unremarkable.

Discussion

In severe pectus excavatum with cardiac compression, forward bending can decrease central venous return and cardiac output, causing hypotension, arrhythmia, and cardiac arrest. In absence of structural or electric abnormalities, cardiac compression by severe pectus excavatum was considered a reversible cause of VF and ICD placement unnecessary. Patients with cardiac compression due to severe pectus excavatum may report pre-existing postural symptoms upon specific request. When these postural symptoms are present, extreme and prolonged forward bending postures should be avoided.

A VIRTUAL Sleep Apnoea management pathway For the work-up of Atrial fibrillation patients in a digital Remote Infrastructure: VIRTUAL-SAFARI

AIMS

In atrial fibrillation (AF) patients, untreated sleep-disordered breathing (SDB) is associated with lower success rates of rhythm control strategies and as such structured SDB testing is recommended. Herein, we describe the implementation of a virtual SDB management pathway in an AF outpatient clinic and examine the utility and feasibility of this new approach.

METHODS AND RESULTS

Prospectively, consecutive AF patients accepted for AF catheter ablation procedures without previous diagnosis of SDB were digitally referred to a virtual SDB management pathway and instructed to use WatchPAT-ONE (ITAMAR) for one night. Results were automatically transferred to a virtual sleep laboratory, upon which a teleconsultation with a sleep physician was planned. Patient experience was measured using surveys. SDB testing was performed in 119 consecutive patients scheduled for AF catheter ablation procedures. The median time from digital referral to finalization of the sleep study report was 18 [11-24] days. In total, 65 patients (55%) were diagnosed with moderate-to-severe SDB. Patients with SDB were prescribed more cardiovascular drugs and had higher body mass indices (BMI, 29 ± 3.3 vs. 27 ± 4.4kg/m2, P < 0.01). Patients agreed that WatchPAT-ONE was easy to use (91%) and recommended future use of this virtual pathway in AF outpatient clinics (86%). Based on this remote SDB testing, SDB treatment was recommended in the majority of patients.

CONCLUSION

This novel virtual AF management pathway allowed remote SDB testing in AF outpatient clinics with a short time to diagnosis and high patient satisfaction. Structured SDB testing results in a high detection of previously unknown SDB in AF patients scheduled for AF ablation.

Clinical utility of rhythm control by electrical cardioversion to assess the association between self-reported symptoms and rhythm status in patients with persistent atrial fibrillation

Background

The best strategy to assess the association between symptoms and rhythm status (symptom-rhythm correlation) in patients with atrial fibrillation (AF) remains unclear. We aimed to determine the clinical utility of rhythm control by electrical cardioversion (ECV) to assess symptom-rhythm correlation in patients with persistent AF.

Methods

We used ECV to examine symptom-rhythm correlation in 81 persistent AF patients. According to current clinical practice, the presence of self-reported symptoms before ECV and at the first outpatient clinic follow-up visit (within 1-month) was assessed to determine the prevalence of a symptom-rhythm correlation (defined as self-reported symptoms present during AF and absent in sinus rhythm or absent in AF and yet relief during sinus rhythm). In addition, we evaluated symptom patterns around ECV.

Results

Only in 18 patients (22%), a symptom-rhythm correlation could be documented. Twenty-eight patients (35%) did not show any symptom-rhythm correlation and 35 patients (43%) had an unevaluable symptom-rhythm correlation as these patients were in symptomatic AF both at baseline and at the first outpatient AF clinic follow-up visit. Importantly, self-reported symptom patterns around ECV were intra-individually variable in 10 patients (12%) without symptom-rhythm correlation (of which 9 patients (11%) had AF recurrence) and in 2 patients (2%) with an unevaluable symptom-rhythm correlation.

Conclusions

In patients with persistent AF, symptom assessment around rhythm control by ECV, once before ECV and once within 1-month follow-up, rarely identifies a symptom-rhythm correlation and often suggests changes in symptom pattern. Better strategies are needed to assess symptom-rhythm correlation in patients with persistent AF.

Electrocardiographic predictors of infrahissian conduction disturbances in myotonic dystrophy type 1

Aims

The aim of this study was to determine electrocardiographic (ECG) criteria predicting abnormal infrahissian conduction in patients with myotonic dystrophy type 1 (DM1), as these criteria could be used to identify the need for an electrophysiological study (EPS).

Methods and results

A retrospective multicentre study was conducted including DM1-affected individuals who underwent EPS between 2007 and 2018. For each individual, EPS indication, His-ventricle (HV) interval, resting ECG parameters prior to EPS, left ventricular ejection fraction (LVEF), neurological status, and DM1 DNA analysis results were collected. Electrocardiographic parameters of patients with a normal HV interval were compared with ECG parameters of patients with a prolonged HV interval. Logistic regression was performed to determine predictors for a prolonged HV interval of ≥70 ms on EPS and diagnostic accuracy of ECG parameters was ascertained. Among 100 DM1-affected individuals undergoing EPS, 47 had a prolonged HV interval. The sole presence of a PR interval >200 ms [odds ratio (OR) 8.45, confidence interval (CI) 2.64–27.04] or a QRS complex >120 ms (OR 9.91, CI 3.53–27.80) on ECG were independent predictors of a prolonged HV interval. The combination of both parameters had a positive predictive value of 78% for delayed infrahissian conduction on EPS. His-ventricle interval was independent of DM1 genetic mutation size, neuromuscular status, and LVEF.

Conclusion

The combination of a prolonged PR interval and widened QRS complex on ECG accurately predicts abnormal infrahissian conduction on EPS in patients with DM1. These ECG parameters could be used as a screening tool to determine the need for referral to a specialized multidisciplinary neuromuscular team with EPS capacity.

Implementation of an on-demand app-based heart rate and rhythm monitoring infrastructure for the management of atrial fibrillation through teleconsultation: TeleCheck-AF

During the coronavirus 2019 (COVID-19) pandemic, outpatient visits in the atrial fibrillation (AF) clinic of the Maastricht University Medical Centre (MUMC+) were transferred into teleconsultations. The aim was to develop anon-demand app-based heart rate and rhythm monitoring infrastructure to allow appropriatmanagement of AF through teleconsultation. In line with the fundamental aspects of integrated care, including actively involving patients in the care process and providing comprehensive care by a multidisciplinary team, we implemented a mobile health (mHealth) intervention to support teleconsultations with AF patients: TeleCheck-AF. The TeleCheck-AF approach guarantees the continuity of comprehensive AF management and supports integrated care through teleconsultation during COVID-19. It incorporates three important components: (i) a structured teleconsultation ('Tele'), (ii) a CE-marked app-based on-demand heart rate and rhythm monitoring infrastructure ('Check'), and (iii) comprehensive AF management ('AF'). In this article, we describe the components and implementation of the TeleCheck-AF approach in an integrated and specialized AF-clinic through teleconsultation. The TeleCheck-AF approach is currently implemented in numerous European centres during COVID-19.

Long-term intermittent versus short continuous heart rhythm monitoring for the detection of atrial fibrillation recurrences after catheter ablation

BACKGROUND

The utility of long-term intermittent heart rhythm monitoring after atrial fibrillation (AF) ablation remains unclear. Therefore, we compared the efficacy and usability of long-term intermittent (AliveCor Kardia® (ACK)) versus short continuous (Holter) heart rhythm monitoring for the detection of AF recurrences after AF ablation and evaluated ACK accuracy to detect AF.

METHODS

Patients were provided with Holter (for ≥24 h) simultaneously with an ACK (4 weeks) used three times a day and in case of symptoms. The primary endpoint was the difference in proportion of patients diagnosed with recurrent AF by ACK as compared to Holter monitoring. Secondary endpoints were the usability (System Usability Scale and a four-item questionnaire) of ACK and Holter monitoring; and the accuracy of the ACK algorithm for AF detection.

RESULTS

Out of 126 post-ablation patients, 115 (91.3%; 35 females, median age 64.0 [58.0-68.0] years) transmitted overall 7838 ACK ECG recordings. ACK and Holter monitoring detected 29 (25.2%) and 17 (14.8%) patients with AF recurrences, respectively (p < 0.001). More than 2 weeks of ACK monitoring did not have additional diagnostic yield for detection of AF recurrences. Patients graded ACK higher than Holter monitoring and found ACK more convenient in daily usage than Holter (p < 0.001). Sensitivity and specificity of ACK for AF detection were 95.3% and 97.5%, respectively.

CONCLUSIONS

Long-term intermittent monitoring by ACK more effectively detects AF recurrences after AF ablation and has a higher patients' usability than short continuous Holter monitoring. ACK showed a high accuracy to detect AF.

Impact of left atrial volume, sphericity, and fibrosis on the outcome of catheter ablation for atrial fibrillation

INTRODUCTION

To investigate the relation between left atrial (LA) volume, sphericity, and fibrotic content derived from contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) and their impact on the outcome of catheter ablation for atrial fibrillation (AF).

METHODS AND RESULTS

In 83 patients undergoing catheter ablation for AF, CE-CMR was used to assess LA volume, sphericity, and fibrosis. There was a significant correlation between LA volume and sphericity (R  =  0.535, P < 0.001) and between LA volume and fibrosis (R  =  0.241, P  =  0.029). Multivariate analyses demonstrated that LA volume was the strongest independent predictor of AF recurrence after catheter ablation (1.019, P  =  0.018).

CONCLUSION

LA volume, sphericity, and fibrosis were closely related; however, LA volume was the strongest predictor of AF recurrence after catheter ablation.

Effect of pulmonary vein anatomy and left atrial dimensions on outcome of circumferential radiofrequency catheter ablation for atrial fibrillation

Multislice computed tomography (MSCT) is commonly acquired before radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) to plan and guide the procedure. MSCT allows accurate measurement of the left atrial (LA) and pulmonary vein (PV) dimensions and classification of the PV anatomy. The aim of the present study was to investigate the effect of LA dimensions, PV dimensions, and PV anatomy on the outcome of circumferential RFCA for AF. A total of 100 consecutive patients undergoing RFCA for AF (paroxysmal 72%, persistent 28%) were studied. The LA dimensions, PV dimensions, and PV anatomy were evaluated three dimensionally using MSCT. The PV anatomy was classified as normal or atypical according to the absence/presence of a common trunk or additional veins. After a mean follow-up of 11.6 ± 2.8 months, 65 patients (65%) maintained sinus rhythm. The enlargement of the left atrium in the anteroposterior direction on MSCT was related to a greater risk of AF recurrence. No relation was found between the PV dimensions and the outcome of RFCA. In addition, normal right-sided PV anatomy was related to a greater risk of AF recurrence compared to atypical right-sided PV anatomy. Multivariate analysis showed that an anteroposterior LA diameter on MSCT (odds ratio 1.083, p = 0.027) and normal right-sided PV anatomy (odds ratio 6.711, p = 0.006) were independent predictors of AF recurrence after RFCA. In conclusion, enlargement of the anteroposterior LA diameter and the presence of normal anatomy of the right PVs are independent risk factors for AF recurrence. No relation was found between the PV dimensions and outcome of RFCA.

Reversed polarity of bipolar electrograms for predicting a successful ablation site in focal idiopathic right ventricular outflow tract arrhythmias

BACKGROUND

Radiofrequency catheter ablation (RFCA) for idiopathic right ventricular outflow tract (RVOT) arrhythmias is typically guided by local activation time (LAT) mapping and unipolar electrogram morphology (QS configuration). However, LAT mapping is limited by the large variation among patients, and the area demonstrating a QS configuration of the unipolar electrogram may be larger than the focal source. Reversed polarity has been proposed as a criterion for guiding RFCA.

OBJECTIVE

The purpose of this study was to investigate the value of reversed polarity of adjacent bipolar electrograms for predicting a successful ablation site in idiopathic RVOT arrhythmias.

METHODS

Twenty-five consecutive patients (12 men [48%], age 43 ± 15 years) undergoing RFCA for RVOT arrhythmia were studied. Electrograms of ablation sites and of points within a 15-mm radius to the successful site were evaluated for LAT, unipolar electrogram morphology, and the presence of reversed polarity of adjacent bipolar electrograms. Electrogram characteristics of successful ablation sites were compared to those of nonsuccessful ablation sites. The spatial distribution of each electrogram characteristic was studied.

RESULTS

Successful ablation sites more often demonstrated reversed polarity and had an earlier LAT than nonsuccessful sites. A wide spatial distribution was observed for unipolar electrograms with a QS configuration around the successful ablation site. Mapping based on LAT and reversed polarity had a higher predictive value for a successful ablation site than mapping based on LAT and QS configuration.

CONCLUSION

The presence of reversed polarity has a high predictive value for successful ablation sites in focal idiopathic RVOT arrhythmias and is likely to reduce the number of RFCA applications.

Natriuretic peptide levels predict recurrence of atrial fibrillation after radiofrequency catheter ablation

BACKGROUND

the presence of atrial fibrillation (AF) is related to increased levels of natriuretic peptides. In addition, increased natriuretic peptide levels are predictive of the development of AF. However, the role of natriuretic peptides to predict recurrence of AF after radiofrequency catheter ablation (RFCA) is controversial.

OBJECTIVE

the study aimed to investigate the role of natriuretic peptides in the prediction of AF recurrence after RFCA for AF.

METHODS

pre-procedural amino-terminal pro-atrial natriuretic peptide (NT-proANP) and amino-terminal-pro-B-type natriuretic peptide (NT-proBNP) plasma levels were determined in 87 patients undergoing RFCA for symptomatic drug-refractory AF. In addition, a comprehensive clinical and echocardiographic evaluation was performed at baseline. Left atrial volumes, left ventricular volumes, and function (systolic and diastolic) were assessed. During a 6-month follow-up period, AF recurrence was monitored and defined as any registration of AF on electrocardiogram or an episode of AF longer than 30 seconds on 24-hour Holter monitoring. The role of natriuretic peptide plasma levels to predict AF recurrence after RFCA was studied.

RESULTS

During follow-up, 66 patients (76%) maintained sinus rhythm, whereas 21 patients (24%) had AF recurrence. Patients with AF recurrence had higher baseline natriuretic peptide levels than patients who maintained sinus rhythm (NT-proANP 3.19 nmol/L [2.55-4.28] vs 2.52 nmol/L [1.69-3.55], P = .030; NT-proBNP 156.4 pg/mL [64.1-345.3] vs 84.6 pg/mL [43.3-142.7], P = .036). However, NT-proBNP was an independent predictor of AF recurrence, whereas NT-proANP was not. Moreover, NT-proBNP had an incremental value over echocardiographic characteristics to predict AF recurrence after RFCA.

CONCLUSION

baseline NT-proBNP plasma level is an independent predictor of AF recurrence after RFCA.

Prediction of Cardiac Resynchronization Therapy Response

Background— Left ventricular (LV) fibrosis is important for the response to cardiac resynchronization therapy (CRT). Calibrated integrated backscatter derived by 2D echocardiography quantifies myocardial ultrasound reflectivity, which may provide a surrogate of LV fibrosis. The aim of the study was first, to investigate the relation of myocardial ultrasound reflectivity assessed with calibrated integrated backscatter on CRT response, and second, to explore the “myocardial ultrasound reflectivity–CRT response” relation in patients with ischemic and nonischemic heart failure (HF).

Methods and Results— One hundred fifty-nine patients with HF referred for CRT underwent an extensive echocardiographic evaluation at baseline and at 6-month follow-up. LV dyssynchrony was derived from speckle-tracking analysis. Calibrated integrated backscatter was obtained from the parasternal long-axis view. The mean value of calibrated integrated backscatter of the anteroseptal and posterior wall was used to estimate myocardial ultrasound reflectivity. CRT response was defined as reduction ≥15% of LV end-systolic volume. At baseline, LV dyssynchrony was significantly larger in responders as compared with nonresponders (188�96 ms versus 115�68 ms, P <0.001), and CRT responders showed less myocardial ultrasound reflectivity as compared with nonresponders (−20.8�3.0 dB versus −17.0�3.0 dB, P <0.001). In multivariable logistic regression analysis, independent predictors for CRT response were LV dyssynchrony, renal function, and myocardial ultrasound reflectivity. Importantly, myocardial ultrasound reflectivity provided an incremental value to CRT response (χ 2 change=40, P <0.001). Considering patients with ischemic HF, the only independent predictor of CRT response was myocardial ultrasound reflectivity, whereas in patients with nonischemic HF, independent predictors of LV reverse remodeling were myocardial ultrasound reflectivity, LV dyssynchrony, and renal function.

Conclusions— Assessment of myocardial ultrasound reflectivity is important in the prediction of CRT response in ischemic and nonischemic patients.

Image integration in catheter ablation of atrial fibrillation

Over the past few years, integration of different imaging modalities to guide catheter ablation procedures for atrial fibrillation has become possible. Various strategies are nowadays available that allow integration of the anatomical information provided by fluoroscopy, computed tomography, magnetic resonance imaging, or intracardiac echocardiography with the information provided by electroanatomic mapping. This review discusses the different image integration techniques, and an overview of the clinical experience with these systems will be provided. In addition, factors that may affect the accuracy of the image integration process will be addressed. Finally, the effect of image integration on procedural characteristics and outcome will be reviewed.