Dubious effect of the high biventricular paced beats percentage itself on the cardiac resynchronization efficacy in patients with atrial fibrillation. The randomized Pilot-CRAfT Study results

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Institute of Cardiology statutory grant

Background

The presence of atrial fibrillation (AF) in cardiac resynchronization therapy (CRT) recipients is common and AF is a marker of poorer CRT response. The negative influence of AF on CRT efficacy is belived to be mediated mainly by the drop of effectively captured biventricular paced beats percentage (BiVp%). According to observational trials, the minimal BiVp associated with better outcomes is 95-98%, however there is lack of randomized trials to confirm this findings.

Purpose

The purpose of the study was to assess the influence of BiVp% itself on the clinical outcomes in the population CRT patients with atrial fibrillation in a prospective, randomized cohort.

Methods

The study included the prospective Pilot-CRAfT study participants that is patients with CRT and permanent or persistent AF lasting for ≥6 months that were randomly assigned to rhythm or rate control strategy. We divided the whole study population according to their BiVp at the 12 month follow-up with two borderline BiVp values (BiVp >98% vs <98% and >95% vs <95%) and analysed the echocardiographic indices, exercise tolerance and quality of life between the prespecified groups.

Results

The study included 43 CRT patients (97,7% males) aged 68,4 (SD: ±8,3) years with mean BiVp% 82,4% ±9,7% at baseline. The mean baseline left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDD) and maximal oxygen uptake (VO2max) were: 30 ±8%, 65 ±8 mm, 14 ±5 mL/(kg*min), respectively. In both of the study arms the BiVp% raised significantly reaching 98,1 ±2,3% and 96,3 ±3,9% in the rhythm control and the rate control arms respectively (P=0,093). As a result the were overall 21 patients with BiVp >98% and 29 patients with BiVp >95% at the end of the study. The BiVp groups >98% vs <98% and >95% vs <95% did not differ as to baseline characteristics and we have not observed any differences in the mean LVEF, mean LVEDD, mean VO2max, and quality of life in the prespecified BiVp% groups at the end of the follow up. Moreover no linear correlations between the BiVp% and LVEF, LVEDD, VO2max values were observed. However, in the rate control group patients with AVNA performed had lower LVEDD at the end of the study (57,7 ±3,0 vs 65,4 ±7,0 p=0,007) and significant decrease in the LVEDD after AVNA was observed (-8,6 95%CI [-14,9; -2,3]).

Conclusions

The BiVp >98% or >95% alone does not seem to warrant good response to cardiac resynchronization in patients with persistent atrial fibrillation as assessed in the prospective randomized cohort. However, performing AVNA in this group of patients may be beneficial in terms of LVEDD decrease.

Rhythm or rate control strategy in CRT recipients with long-standing persistent atrial fibrillation - preliminary results of the PilotCRAfT study

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): National Institute of Cardiology in Warsaw Statutory Grant

Background

The presence of atrial fibrillation (AF) in cardiac resynchronization therapy (CRT) recipients is common and AF is a marker of poorer CRT response. The negative influence of AF on CRT efficacy is mediated mainly by the drop of the effectively captured biventricular paced beats percentage (BiVp%) which should exceed 95-98% to warrant good CRT response.  Sinus rhythm (SR) restoration may improve CRT efficacy which in turn may protect AF recurrence. However, there is lack of randomized studies comparing rhythm and rate control strategies in these patients.

Purpose

The purpose of the Pilot-CRAfT study (NCT01850277) was to compare the efficacy of rhythm vs rate control strategy in CRT patients with long-standing persistent or permanent atrial fibrillation.

Methods

The study included patients with CRT and permanent or persistent AF lasting for ≥6 months, resulting in BiVp% <95%, who were randomly assigned to rhythm or rate control strategy. The rhythm control strategy comprised of external electrical cardioversion (EEC). The rate control strategy included pharmacotherapy and atrioventricular node ablation (AVNA) as needed. Both of the study arms received amiodarone. The follow-up lasted 12 months. The primary endpoint was the 12-month BiVp%. The patients underwent ECHO, cardiopulmonary test, quality of live (QoL) and clinical outcomes assessment.  

Results

The study included 43 CRT patients (97,7% males) aged 68,4 (SD: ±8,3) years with mean BiVp% 82,4% ±9,7% at baseline. The mean duration of AF paroxysm was 25 ±19 months. The mean baseline left ventricular ejection fraction (LVEF), left atrium area and maximal oxygen uptake (VO2max) were: 30 ±8%, 33 ±7 cm2, 14 ±5 mL/(kg*min), respectively. The EEC was performed in 19 out of 22 patients assigned to the rhythm control arm. The immediate success rate of EEC was 58%. 42% of  the rhythm control arm patients remained in SR after 12 months. In the rate control group 1 person underwent AVNA and in 1 patient spontaneous SR resumption was observed. After 12 months there was significant BiVp% increase in both the rhythm and the rate control arms (98,1 ±2,3 vs 96,3 ±3,9%, respectively. The BiVp% differences between the groups were not significant (P = 0,093). However, in the per protocol analysis, the rhythm control group had greater LVEF after 12 months as opposed to the rate control arm (36,8% vs 29,9% respectively, P = 0,039). The LVEF raised significantly in the rhythm control group (ΔLVEF 5,0 (95%CI: 1,54; 8,46)). No significant differences between the groups in the VO2max, QoL, clinical and safety end-points were noticed.

Conclusions

Structured follow-up of CRT patients with long-standing persistent or permanent AF leads to significant BiVp% increase exceeding 95%. The rate control strategy did not improve CRT effectivness, irrespective of high BiVp%. However limited in the efficacy, the rhythm control strategy may improve CRT outcome in these patients, resulting in LVEF increase.

Glasgow Coma Scale score of more than four on admission predicts in-hospital survival in patients after out-of-hospital cardiac arrest

AIM

The aim of the study was to assess the usefulness of the Glasgow Coma Scale (GCS) score assessed by EMS team in predicting survival to hospital discharge in patients after out-of-hospital cardiac arrest (OHCA).

METHODS

Silesian Registry of OHCA (SIL-OHCA) is a prospective, population-based regional registry of OHCAs. All cases of OHCAs between the 1st of January 2018 and the 31st of December 2018 were included. Data were collected by EMS using a paper-based, Utstein-style form. OHCA patients aged ≥18 years, with CPR attempted or continued by EMS, who survived to hospital admission, were included in the current analysis. Patients who did not achieve return of spontaneous circulation (ROSC) in the field, with missing data on GCS after ROSC or survival status at discharge were excluded from the study.

RESULTS

Two hundred eighteen patients with OHCA, who achieved ROSC, were included in the present analysis. ROC analysis revealed GCS = 4 as a cut-off value in predicting survival to discharge (AUC 0.735; 95%CI 0.655-0.816; p < 0.001). Variables significantly associated with in-hospital survival were young age, short response time, witnessed event, previous myocardial infarction, chest pain before OHCA, initial shockable rhythm, coronary angiography, and GCS > 4. On the other hand, epinephrine administration, intubation, the need for dispatching two ambulances, and/or a physician-staffed ambulance were associated with a worse prognosis. Multivariable logistic regression analysis revealed GCS > 4 as an independent predictor of in-hospital survival after OHCA (OR of 6.4; 95% CI 2.0-20.3; p < 0.0001). Other independent predictors of survival were the lack of epinephrine administration, previous myocardial infarction, coronary angiography, and the patient's age.

CONCLUSION

The survival to hospital discharge after OHCA could be predicted by the GCS score on hospital admission.

P429The efficacy of electrical cardioversion of long-standing persistent or permanent atrial fibrillation in cardiac resynchronization therapy recipients

Funding Acknowledgements

Institute of Cardiology statutory grant (grant no.: 2.30/VII/13)

Background

Atrial fibrillation (AF) and heart failure (HF) often co-exist and influence each other. The presence of AF is often regarded as a marker of HF severity.  Moreover, AF in cardiac resynchronization therapy (CRT) recipients hinders the CRT effectiveness in HF treatment by the reduction of the percentage of biventricular paced beats (BiVp%). Sinus rhythm (SR) restoration makes CRT more effective in HF treatment which may protect AF recurrence.

Purpose

To establish the effectiveness of electrical external cardioversion (EEC) in CRT patients with long-standing persistent AF or permanent, pre-treated with amiodarone.

Methods

The population of the study comprised of the Pilot-CRAfT study participants (NCT01850277), that is patients with CRT, long-standing persistent or considered as permanent AF and BiVp ≤ 95% who were randomly assigned to the "rhythm control" or the "rate control" strategy. The inclusion criteria included an AF paroxysm lasting at least 6 months. Both treatment arms received amiodarone beginning with the loading dose. Subsequently, patients assigned to the rhythm control strategy underwent electrical cardioversion. Rate control strategy included pharmacotherapy and atrioventricular node ablation, as needed. The follow up visit was performed 3 months after the enrolment visit. The EEC effectiveness, an AF recurrence within the 3 month period, BiVp% changes, the EEC parameters  and the EEC related complications were analysed.

Results

Out of 48 participants enrolled in the Pilot-CRAfT study, 25 patients were assigned to the rhythm control arm. The mean age of the rhythm control arm patients was 69,5 years , the mean left ventricular ejection fraction was 30,6% , the mean left atrium diameter was 53 mm and the median duration of persistent AF was 16 months. SR was obtained in 12 out of 20 (60%) patients who underwent the EEC . On the 3 month visit 8 patients remained in SR (40%). In patients with an AF paroxysm lasting less than 1 year the success rate was 100% vs 50% in the AF lasting 1 year at least (p = 0,11 ). After 3 months, SR remained in 100% vs 25% of patients, respectively (p =0,015.).  The effectiveness of anterior-posterior EEC electrodes placement was 20% and it was 71% for the anterior-lateral patch location . The EEC resulted in significant BiVp% rise - also in the whole intention-to-treat (ITT) group:  88,58%  before the EEC vs 96,68% after the EEC  (p = 0,002). No severe adverse events of the EEC were observed.

Conclusions

The electrical cardioversion of persistent atrial fibrillation lasting more than 6 months in patients with severe HF and treated with CRT is characterised by modest success rate, even after the amiodarone pre-treatment. However, the ECC ensures significant rise in BiVp% close to 97%, even in the whole EEC group based on the ITT principle. The AF paroxysm duration &lt;1 year and the anterior-posterior patch placement may ensure better EEC efficacy in this group of patients.

P1464A question of gender equality. Sex-related differences in survival after primary prevention implantable cardioverter-defibrillator implantation for dilated cardiomyopathy An analysis from POLKARD

OnBehalf

POLKARD Polish ICD Registry

Background

The protective effects of implantable cardioverter defibrillators (ICDs) in the primary prevention of sudden cardiac death of patients presenting with left ventricular (LV) systolic dysfunction are unequivocal. Nevertheless, female underrepresentation has been a consistent finding in all randomized controlled primary prevention ICD trials. Surprisingly, there is a vast body of literature on female primary prevention ICD patients exhibit a lower overall mortality.

Purpose

Therefore, we analyzed data from a large, nationwide POLKARD registry to evaluate the effect of sex on survival after primary prevention cardioverter-defibrillator implantation for dilated cardiomyopathy.

Methods

All patients enrolled in the Polish ICD Registry from 2008 to 2014 were identified. Patients were included in the study if they were designated as receiving an ICD for primary prevention of SCD after documented non-ischeamic cardiomyopathy. Kaplan-Meier survival analysis was used to assess all-cause mortality.

Results

Of the 964 ICD recipients, 241 (25%) were women (mean age of 64± 0,45 years). During a mean follow-up of 5,53 ± 2,48 years 32% of women and 42% of men died. Kaplan-Meier curve depicted a significantly lower mortality for women than for men (p = 0,05). The median survival time was 6,73 years (55 deaths per 1000 person-years) versus 6,37 years (78 deaths per 1000 person-years) for women and men, respectively.

Conclusions

In agreement with previous studies, our data indicate that primary prevention implantation rates for dilated cardiomyopathy are lower in women. However, the reasons are not entirely understood.

P1463Regional variation in survival rates among primary prevention implantable cardioverter-defibrillator recipients in Eastern and Northern Europe POLKARD Polish ICD Registry perspective

Funding Acknowledgements

None.

OnBehalf

POLKARD Polish ICD Registry

Objective

The findings of Danish Study to assess the efficiency of ICD in patients with non ischemic heart failure has recently raised questions about the current strategy of ICD implantation for the primary prevention of sudden cardiac death. POLKARD - Polish ICD Registry is a prospective, non-randomised, central registry of patients who are referred for an implantation of an ICD in Poland. The Registry contains prospectively collected follow-up data including mortality.

Purpose

To compare survival rates between Polish and Danish ‘real-world’ non-ischemic primary prevention cohorts.

Methods

Retrospective analysis of clinical characteristics and long-term follow-up of patients referred for primary prophylactic implantable cardioverter defibrillator (ICD) implantation in Poland between April 2008 and November 2014 was performed. The primary outcome of the trial was all-cause mortality. Results: The polish study cohort was large (964) as compared to Danish population randomized to receive ICD therapy (556). The median follow-up time in DANISH Study and Polish ICD Registry was 67,6 and 77 months, respectively. Compared with patients enrolled in the DANISH Study, patients in the Polish ICD Registry were age-similar. However, the polish study population was male-dominated. What is more, male gender was identified as a risk factor for long-term mortality in polish study population (p = 0.005). In the matched cohorts, there was difference in survival between DANISH Study and Polish ICD Registry patients (all-cause mortality rates: 21,6% - 44 events per 1000 person-years and 39,3% - 72 events per 1000 person-years, respectively).

Conclusions

Our findings imply that survival among patients who receive a primary prevention ICD for non-ischemic cardiomyopathy in clinical practice in Central Europe is different from Northern Europe.

P990Assessment of clinical risk factors for all-cause mortality among hypertrophic cardiomyopathy patients with ICDs

Introduction

According to the literature, the annual mortality rate of hypertrophic cardiomyopathy (HCM) patients is estimated to 1–2%. Sudden cardiac death (SCD), heart failure and thromboembolism are the main causes of death among this population. Patients at high risk for SCD, identified using HCM risk score, are qualified for ICD implantation. Unfortunately for clinicians, there is no validated model or statistical tool for assessment of the risk of mortality within the HCM patients with ICDs.

Purpose

The aim of this study was to determine the main risk factors of all- cause mortality in HCM patients with ICDs.

Methods

The long-term follow-up of group of 104 consecutive patients with HCM, who had the ICD implanted between 1996 and 2006 in tertiary reference clinical unit was performed. Twenty patients who died during observation were the subject of the current analysis. ICD was implanted for primary (n=16) and secondary (n=4) prevention of SCD within this subpopulation. Analysis were performed for mentioned below potential risk factors: age at the time of implantation, syncopes, family history of SCD, atrial fibrillation/supraventricular tachycardia, decreased left ventricular ejection fraction (LVEF), non-sustained ventricular tachycardia (nsVT), maximum left ventricular wall thickness, abnormal exercise blood pressure response, left ventricular outflow tract obstruction.

Results

The average time of survival since ICD implantation was 8,5±4,6 years. Decreased LVEF (Wald chi2 4,57; p=0,033), secondary prevention (Wald chi2 8,57; p=0,003), family history of SCD (Wald chi2 4,93; p=0,026) and episodes of nsVT (Wald chi2 3,49; p=0,062) are the clinical risk factors that significantly affect the time of survival. The probability of death, expressed as Hazard Ratio, was 27-fold higher in secondary prevention group (HR=27,18), almost 10-fold higher in patients with positive family history of SCD (HR=9,74) and 3,7-fold higher when nsVT was detected. The cause of death was established in 16/20 patients. In 15 cases, these were deaths from cardiovascular causes: end-stage heart failure (8), complications of heart transplantation or circulatory support (4), SCD (1) and other cardiovascular (2).

Conclusion

Secondary prevention, positive family history of SCD, nsVT and decreased LVEF seem to be the most significant risk factors associated with all- cause mortality in HCM patients with ICDs. Despite the ICD implantation, subpopulation studied had poor prognosis with high incidence of progression to end-stage heart failure. Further studies to create validated model for assessment of death risk in long-term observation of patients with HCM after ICD implantation are required.

P2878Higher all-cause mortality in patients with implanted dual-chamber cardioverter-defibrillators for secondary prevention: an analysis from the Polish ICD Registry

Background

In the Polish ICD Registry population secondary prevention recipients account for over 27%. Despite the evolution of indications for secondary prevention implantable cardioverter defibrillators (ICDs), recommendations regarding the use of ICDs for secondary prevention of sudden cardiac death (SCD) rely on information from a small number of randomized controlled trials that were performed decades ago, with mixed results. Moreover, research on the outcomes after implantations for secondary prevention of ICDs is limited. While dual-chamber devices offer theoretical advantage over single-chamber devices, dual-chamber ICDs (DC-ICDs) were announced not superior to single-chamber (SC-ICDs) in some research.

Purpose

Therefore, the aim of the study was to evaluate the all-cause mortality among patients from the Polish ICD Registry receiving either a single- or a dual-chamber device for secondary prevention in contemporary clinical practice.

Methods

All patients enrolled in the Polish ICD Registry from 1995 to 2016 were identified. Patients were included in the study if they were designated as receiving an ICD for secondary prevention of SCD after documented tachycardic arrest, sustained ventricular tachycardia (VT), or syncope. Kaplan-Meier survival analysis was used to assess all-cause mortality.

Results

In the study population of 3596 ICD recipients (mean age 69±12 years, 81% male, SC-ICD 61%, DC-ICD 39%), during mean follow-up of 79±43 months all-cause mortality rate was higher in the dual-chamber group than in the single chamber group, with a significant difference between the two groups as depicted in Kaplan-Meier curve (p<0,05). The median survival time was 98 months versus 110 months for SC and DC-ICD, respectively.

Conclusions

This study is the first to describe the characteristics of a national cohort of patients receiving a secondary prevention ICD in such a long follow-up period in contemporary practice. Implantation of a dual-chamber ICD was associated with higher all-cause mortality compared with single chamber devices.

Sex-Related Procedural Aspects and Complications in CRT Survey II: A Multicenter European Experience in 11,088 Patients

OBJECTIVES

This study sought to compare sex difference for procedural aspects and complications in the European Society of Cardiology CRT Survey II, exploring whether adverse events were related to the type of CRT device implanted.

BACKGROUND

Sex-related differences in procedural aspects and complications in patients undergoing cardiac resynchronization therapy (CRT) implantation has not been explored in a real-life population.

METHODS

A post-hoc analysis of procedural data and complications in different sexes and factors associated with events was performed from data collected in the European Society of Cardiology CRT Survey II.

RESULTS

Of all patients (n = 11,088) included, 24.3% were women. The mean age (70 years of age) of male and female recipients was similar. Female patients more frequently had an idiopathic cardiomyopathy (67.4% vs. 44.1%) and fewer comorbidities, including atrial fibrillation (34.8% vs. 42.8%), diabetes (29.1% vs. 32.1%), chronic obstructive lung disease (10.3% vs. 12.6%), and renal failure (28.7% vs. 31.9%), compared with men. More women compared with men had a pacemaker (56.6% vs. 46.3%) and much less often an implantable cardioverter-defibrillator (CRT-D) (19.0% vs. 34.7%) implant. Periprocedural event rate was the highest in women with CRT with defibrillator (7.1% vs. 4.8% in men), followed by women with a CRT with pacing (5.5% vs. 4.4% in men). The higher periprocedural event rate in CRT-D women was attributable primarily to the occurrence of pneumothorax (1.4%), coronary sinus dissection (2.1%), and pericardial tamponade (0.3%). The rate of in-hospital major adverse events (6.0%) and complications necessitating reoperation (4.0%) was not different among sex and device type.

CONCLUSIONS

Women are more likely to experience adverse procedure-related events during CRT implantation. Thus, preventive strategies should be employed to minimize complication rate.

An analysis of the relationship between the applied medical rescue actions and the return of spontaneous circulation in adults with out-of-hospital sudden cardiac arrest

Sudden cardiac arrest (SCA) is a significant medical and social issue, the main cause of death in Europe and the United States.The aim of the research was to evaluate the effectiveness of emergency medical procedures applied by emergency medical teams in prehospital care in the context of return of spontaneous circulation (ROSC).The case-control study was based on the medical documentation of the Rescue Service in Katowice (responsible for monitoring 2.7 million inhabitants of the region) referring to 2016. The research involved exclusively adults (ie, individuals older than 18 years) with out-of-hospital cardiac arrest (OHCA). After considering the above inclusion criteria, there were 1603 dispatch order forms (0.64% of all dispatch orders) involved in further research.On the basis of the emergency medical procedure forms, the actions of emergency medical teams were verified as medical procedures (endotracheal intubation, the use of suction pumps, defibrillation, the use of alternatives providing airway patency and ROSC was determined.The analysis covered 1603 cases of OHCA. SCA turned out more frequent in men than in women (P = .000). Most often, SCA occurred in domestic conditions during the day and was witnessed by a third person. In 59.9% of the cases, actions were taken by witnesses, which increased the probability of ROSC. Patients were usually intubated (51.4%). Respirators were used less frequently (20.2%). Ventricular fibrillation (VF) was reported only in 22.0% of the cases. The ROSC rate was higher in the group of patients with diagnosed VF than in those with nonshockable rhythms (VF, 55.43% vs asystole, 24.05%; P = .000).Successful resuscitation depends on the quality of emergency medical procedures performed at the place of incident. The highest probability of ROSC is related with defibrillation (in the cases of VF or ventricular tachycardia with no pulse), intubation, the application of a respirator, and performing mechanical ventilation, as well as with a shorter time from dispatch to arrival.

Upgrades from a previous device compared to de novo cardiac resynchronization therapy in the European Society of Cardiology CRT Survey II

BACKGROUND

To date, there are no data from randomized controlled studies on the benefit of cardiac resynchronization therapy (CRT) when implanted as an upgrade in patients with a previous device as compared to de novo CRT. In the CRT Survey II we compared the baseline data of patients upgraded to CRT (CRT-P/CRT-D) from a previous pacemaker (PM) or implantable cardioverter-defibrillator (ICD) to de novo CRT implantation.

METHODS AND RESULTS

In the European CRT Survey II, clinical practice data of patients undergoing CRT and/or ICD implantation across 42 European Society of Cardiology (ESC) countries were collected between October 2015 and December 2016. Out of a total of 11 088 patients, 2396 (23.2%) were upgraded from a previous PM or ICD and 7933 (76.8%) underwent de novo implantation. Compared to de novo implantations, upgraded patients were older, more often male, more frequently had ischaemic heart failure aetiology, atrial fibrillation, reduced renal function, worse heart failure symptoms, and higher N-terminal pro-B-type natriuretic peptide levels. Upgraded patients were more often PM-dependent and less frequently received CRT-D. Total peri-procedural, in-hospital complications and length of hospital stay were similar. Upgraded patients were less frequently treated with heart failure medication at discharge.

CONCLUSION

Despite a lack of evidenced-based data, close to one quarter of all CRT implantations across 42 ESC countries were upgrades from a previous PM or ICD. Despite older age and worse symptoms, the CRT implantation procedures in upgraded patients were equally frequently successful and complications similar to de novo implantations. These results call for more studies.

Left ventricular scar and the acute hemodynamic effects of multivein and multipolar pacing in cardiac resynchronization

Background

We sought to determine whether presence, amount and distribution of scar impacts the degree of acute hemodynamic response (AHR) with multisite pacing.

Multi-vein pacing (MVP) or multipolar pacing (MPP) with a multi-electrode left ventricular (LV) lead may offer benefits over conventional biventricular pacing in patients with myocardial scar.

Methods

In this multi-center study left bundle branch block patients underwent an hemodynamic pacing study measuring LV dP/dt_max. Patients had cardiac magnetic resonance scar imaging to assess the effect of scar presence, amount and distribution on AHR.

Results

24 patients (QRS 171 ± 20 ms) completed the study (83% male). An ischemic etiology was present in 58% and the mean scar volume was 6.0 ± 7.0%. Overall discounting scar, MPP and MVP showed no significant AHR increase compared to an optimized “best BiV” (BestBiV) site. In a minority of patients (6/24) receiver-operator characteristic analysis of scar volume (cut off 8.48%) predicted a small AHR improvement with MPP (sensitivity 83%, specificity 94%) but not MVP. Patients with scar volume > 8.48% had a MPP-BestBiV of 3 ± 6.3% vs. −6.4 ± 7.7% for those below the cutoff. There was a significant correlation between the difference in AHR and scar volume for MPP-BestBiV (R = 0.49, p = 0.02) but not MVP-BestBiV(R = 0.111, p = 0.62). The multielectrode lead positioned in scar predicted MPP AHR improvement (p = 0.04).

Conclusions

Multisite pacing with MPP and MVP shows no AHR benefit in all-comers compared to optimized BestBiV pacing. There was a minority of patients with significant scar volume in relation to the LV site that exhibited a small AHR improvement with MPP.

(Study identifier NCT01883141)

CRT Survey II: a European Society of Cardiology survey of cardiac resynchronisation therapy in 11 088 patients-who is doing what to whom and how?

BACKGROUND

Cardiac resynchronisation therapy (CRT) reduces morbidity and mortality in appropriately selected patients with heart failure and is strongly recommended for such patients by guidelines. A European Society of Cardiology (ESC) CRT survey conducted in 2008-2009 showed considerable variation in guideline adherence and large individual, national and regional differences in patient selection, implantation practice and follow-up. Accordingly, two ESC associations, the European Heart Rhythm Association and the Heart Failure Association, designed a second prospective survey to describe contemporary clinical practice regarding CRT.

METHODS AND RESULTS

A survey of the clinical practice of CRT-P and CRT-D implantation was conducted from October 2015 to December 2016 in 42 ESC member countries. Implanting centres provided information about their hospital and CRT service and were asked to complete a web-based case report form collecting information on patient characteristics, investigations, implantation procedures and complications during the index hospitalisation. The 11 088 patients enrolled represented 11% of the total number of expected implantations in participating countries during the survey period; 32% of patients were aged ≥75 years, 28% of procedures were upgrades from a permanent pacemaker or implantable cardioverter-defibrillator and 30% were CRT-P rather than CRT-D. Most patients (88%) had a QRS duration ≥130 ms, 73% had left bundle branch block and 26% were in atrial fibrillation at the time of implantation. Large geographical variations in clinical practice were observed.

CONCLUSION

CRT Survey II provides a valuable source of information on contemporary clinical practice with respect to CRT implantation in a large sample of ESC member states. The survey permits assessment of guideline adherence and demonstrates variations in patient selection, management, implantation procedure and follow-up strategy.

Biventricular Paced QRS Area Predicts Acute Hemodynamic CRT Response Better Than QRS Duration or QRS Amplitudes

INTRODUCTION

Vectorcardiographic (VCG) QRS area of left bundle branch block (LBBB) predicts acute hemodynamic response in cardiac resynchronization therapy (CRT) patients. We hypothesized that changes in QRS area occurring with biventricular pacing (BV) might predict acute hemodynamic CRT response (AHR).

METHODS AND RESULTS

VCGs of 624 BV paced electrocardiograms (25 LBBB patients with 35 different pacing configurations) were calculated according to Frank's orthogonal lead system. Maximum QRS vector amplitudes (X_Ampl , Y_Ampl , Z_Ampl , and 3D_Amp ) and QRS areas (X_Area , Y_Area , Z_Area , and 3D_Area ) in the orthogonal leads (X, Y, and Z) and in 3-dimensional projection were measured. Volume of the 3D vector loop and global QRS duration (QRSD) on the surface electrocardiogram were assessed. Differences (Δ) in VCG parameters between BV paced and LBBB QRS complexes were calculated. An increase of 10% in dP/dt max was considered as AHR. LBBB conduction is characterized by a large Z_Area (109 μVs, interquartile range [IQR]:75;135), significantly larger than X_Area (22 μVs, IQR:10;57) and Y_Area (44 μVs, IQR:32;62, P < 0.001). Overall, QRS duration, amplitudes, and areas decrease significantly with BV pacing (P < 0.001). Of all VCG parameters, 3D_Ampl , Δ3D_Ampl , Z_Area, ΔZ_Area , Δ3D_Area , and ΔQRSD differentiate AHR response from nonresponse (P < 0.05). ΔZ_Area predicted best positive AHR (area under the curve = 0.813) and outperformed any other VCG parameter or QRSD measurement.

CONCLUSION

Of all VCG parameters, reduction in QRS area, calculated in Frank's Z lead, predicts acute hemodynamic response best. This method might be an easy, noninvasive tool to guide CRT implantation and optimization.

Utility of automated template matching for the interpretation of pace mapping in patients ablated due to outflow tract ventricular arrhythmias

AIMS

One of the disadvantages of classic pace mapping (PM) is the operator's subjective interpretation. The aim of this single-centre retrospective study was to evaluate the value of automated template matching (AMT) in patients ablated due to ventricular outflow tract arrhythmias (OTAs).

METHODS AND RESULTS

From an overall group of 105 patients with OTA who were scheduled for transcatheter ablation (TA), AMT was accessible in 42 patients [21 right ventricular outflow tract (RVOT), 21 left ventricular outflow tract (LVOT), 28 women, aged 51.5 ± 12.7 years]. We used AMT to compare spontaneous arrhythmia ORS (spontQRS) with paced QRS complexes during PM in sites where radiofrequency (RF) applications were successful and in sites where RF applications were unsuccessful. The concordance was presented in per cents as objective matching scores (OMS). Then, at the successful ablation sites, we examined the relationship between OMS and the visual interpretation of PM was presented as electrophysiologists matching scores (EMS). The OMS of PM at sites of successful ablation varied from 78 to 99% (mean 94.1 ± 3.8) and from 47 to 95% (mean 80.2 ± 12.6%) at sites of unsuccessful ablation. Pace mapping in unsuccessful RF sites was significantly less similar to spontQRS morphologies than in successful RF sites (P = 0.0001). There was a significant correlation between OMS and EMS (r = 0.82; P < 0.0001). The OMS that indicated optimal ablation site was 89% (sensitivity = 95%; specificity = 80%). The mean OMS for successful sites at RVOT (95.1 ± 1.8%) and LVOT (93.1 ± 4.9%) were not different (P = 0.0551).

CONCLUSION

This analysis revealed that AMT is a valuable technique for the interpretation of PM and for the identification of successful ablation sites in OTA.

Comparison of the rhythm control treatment strategy versus the rate control strategy in patients with permanent or long-standing persistent atrial fibrillation and heart failure treated with cardiac resynchronization therapy - a pilot study of Cardiac Resynchronization in Atrial Fibrillation Trial (Pilot-CRAfT): study protocol for a randomized controlled trial

BACKGROUND

The only subgroups of patients with heart failure and atrial fibrillation in which the efficacy of cardiac resynchronization therapy has been scientifically proven are patients with indications for right ventricular pacing and patients after atrioventricular junction ablation. However it is unlikely that atrioventricular junction ablation would be a standard procedure in the majority of the heart failure patients with cardiac resynchronization therapy and concomitant atrial fibrillation due to the irreversible character of the procedure and a spontaneous sinus rhythm resumption that occurs in about 10% of these patients.

METHODS/DESIGN

Pilot-CRAfT is the first randomized controlled trial evaluating the efficacy of a rhythm control strategy in atrial fibrillation patients with cardiac resynchronization therapy devices. The aim of this prospective, single center randomized controlled pilot study is to answer the question whether the patients with cardiac resynchronization therapy and permanent atrial fibrillation would benefit from a strategy to restore and maintain sinus rhythm (that is 'rhythm control' strategy) in comparison to rate control strategy. The study population consists of 60 patients with heart failure and concomitant long-standing persistent or permanent atrial fibrillation who underwent a cardiac resynchronization therapy device implantation at least 3 months before qualification. Study participants are randomly assigned to the rhythm control strategy (including electrical cardioversion and pharmacotherapy) or to the rate control group whose goal is to control ventricular rate. The follow-up time is 12 months. The primary endpoint is the ratio of effectively captured biventricular beats. The secondary endpoints include peak oxygen consumption, six-minute walk test distance, heart failure symptom escalation, reverse remodelling of the heart on echo and quality of life.

TRIAL REGISTRATION

NCT01850277 registered on 22 April 2013 (ClinicalTrials.gov).

Recurrence of ventricular arrhythmias in patients with non-ischaemic dilated cardiomyopathy: evidence-based predictors

BACKGROUND

Ventricular arrhythmia (VA) is the most frequent cause of sudden death among patients with non-ischaemic dilated cardiomyopathy (DCM).

AIM

To identify the important VA risk factors in patients with DCM.

METHODS AND RESULTS

Eighty-five DCM patients (73 males, mean age 54 years) with DCM and implantable cardioverter defibrillators (ICD) were followed for 21+/-19 months after ICD implantation. The mean follow-up was 21 months. Data from 55 patients with VA recorded in the ICD memory and requiring ICD intervention during follow-up were compared with 30 patients without arrhythmia. Cox regression analysis identified the following univariate predictors of VA: alcoholic aetiology of DCM (0.05), diuretic treatment (0.003), history of cardiac arrest (0.03), right ventricular diastolic diameter (0.001). Both ACE inhibitor (ACEI) and statin treatments were associated with a tendency towards decreased risk of VA. Multivariate logistic analysis identified four predictors as significantly related to VA: alcoholic aetiology (HR 4.8, p=0.008), ACEI treatment (HR 0.4, p=0.01), diuretic treatment (HR 2.6, p=0.015), and statin treatment (HR 0.1, p=0.03).

CONCLUSIONS

The majority of patients with DCM and ICD have recurrences of VA. Alcoholic aetiology of DCM is associated with an increase in the incidence of arrhythmias. Treatment with ACEI and statins is associated with a reduction of arrhythmias.

Delayed paced ventricular activation in the long QT syndrome is associated with ventricular fibrillation

BACKGROUND

LQTS may cause sudden cardiac death (SCD), but the mechanisms linking gene mutations to ventricular fibrillation (VF) are unclear.

OBJECTIVE

To determine whether ventricular activation delays in congenital long QT syndrome (LQTS) are associated with VF and to describe these delays clinically by measuring activation through ventricular myocardium after a premature extrastimulus.

METHODS

Forty-six patients with LQTS, including 16 with VF (LQTS VF) were investigated, and the results were compared with those from 24 patients with hypertrophic cardiomyopathy and VF (HCM VF). Electrograms in response to premature stimuli were analyzed for increases in electrogram duration (DeltaED) and the S1S2 coupling intervals at which electrogram latency starts to increase (S1S2(delay)). Two piecewise continuous straight line segments were fitted to the last electrogram deflection as a function of S1S2 interval in the LQTS and HCM VF populations, and the difference in their gradient (alpha) was taken as an index of the abruptness of the onset of this delay.

RESULTS

Thirteen LQTS VF and six LQTS non-VF patients had values of DeltaED and S1S2(delay) comparable to those in HCM VF patients, while the remainder (three LQTS VF and 24 LQTS non-VF) had lower values (P<.001). There was only a weak correlation between delay and the corrected QT interval. The HCM and LQTS VF patients could be separated by the value of alpha (P<.01), with the LQTS patients having a more abrupt onset of delay.

CONCLUSIONS

Large delays in ventricular activation after an extrastimulus occur in patients with the LQTS, especially those with VF. The change in delay is abrupt in the LQTS, indicating sudden block to activation creating a dynamic substrate for arrhythmogenesis.

Sudden death in noncoronary heart disease is associated with delayed paced ventricular activation

BACKGROUND

Slowed or delayed myocardial activation and dispersed refractoriness predispose to reentrant excitation that may lead to ventricular fibrillation (VF). Increased ventricular electrogram duration (DeltaED) in response to extrastimuli and increased S1S2 coupling intervals at which electrogram duration starts to increase (S1S2delay) are seen both in hypertrophic cardiomyopathy (HCM) in those at risk of VF and in patients with idiopathic VF (IVF).

METHODS AND RESULTS

DeltaED and S1S2delay have been measured using paced electrogram fractionation analysis in 266 patients with noncoronary heart disease. Of these, one group of 61 patients had a history of VF and included 21 HCM, 17 IVF, 13 long-QT syndrome (LQTS), 5 dilated cardiomyopathy (DCM), and 5 others. These were compared with 205 patients with similar diseases with no VF history (non-VF group) and a control group (n=12) without heart disease. Results from HCM VF patients (DeltaED, 19+/-3.3 ms; S1S2delay, 350+/-9.7 ms) differed sharply from observations in HCM non-VF patients (DeltaED, 7.3+/-1.35 ms; S1S2delay, 312+/-6.7 ms; P<0.001). DCM VF patients had longer delays (DeltaED, 14.3+/-5.9; S1S2delay, 344+/-11.2) than DCM non-VF patients (DeltaED, 5.8+/-1.87 ms; S1S2delay, 311+/-5.7 ms; P<0.001), with major differences also seen comparing LQTS VF (DeltaED, 12.4+/-5.3 ms; S1S2delay, 343+/-13.8 ms) and LQTS non-VF patients (DeltaED, 11.0+/-2.7 ms; S1S2delay, 320+/-5.4 ms; P<0.001). IVF patients had both severely abnormal and normal areas of myocardium.

CONCLUSIONS

Slowed or delayed myocardial activation is a common feature in patients with noncoronary heart disease with a history of VF, and its assessment may allow the prospective prediction of VF risk in these patients.