2010 Focused Update of ESC Guidelines on device therapy in heart failure: an update of the 2008 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure and the 2007 ESC Guidelines for cardiac and resynchronization therapy. Developed with the special contribution of the Heart Failure Association and the European Heart Rhythm Association

Very Long-Term Follow-Up in Cardiac Resynchronization Therapy: Wider Paced QRS Equals Worse Prognosis

Background: Different electrocardiogram (ECG) findings are known to be independent predictors of clinical response to cardiac resynchronization therapy (CRT). It remains unknown how these findings influence very long-term prognosis. Methods and Results: A total of 102 consecutive patients (75 males, mean age 65 ± 10 years) referred to our center for CRT implantation had previously been included in this prospective observational study. The same patient group was now re-evaluated for death from all causes over a prolonged median follow-up of 10.3 years (interquartile range 9.4–12.5 years). During follow-up, 55 patients died, and 82% of the clinical non-responders (n = 23) and 44% of the responders (n = 79) were deceased. We screened for univariate associations and found QRS width during biventricular (BIV) pacing (p = 0.02), left ventricular (LV) pacing (p < 0.01), Δ LV paced–right ventricular (RV) paced (p = 0.03), age (p = 0.03), New York Heart Association (NYHA) class (p < 0.01), CHA₂DS₂-Vasc score (p < 0.01), glomerular filtration rate (p < 0.01), coronary artery disease (p < 0.01), non-ischemic cardiomyopathy (NICM) (p = 0.01), arterial hypertension (p < 0.01), NT-proBNP (p < 0.01), and clinical response to CRT (p < 0.01) to be significantly associated with mortality. In the multivariate analysis, NICM, the lower NYHA class, and smaller QRS width during BIV pacing were independent predictors of better outcomes. Conclusion: Our data show that QRS width duration during biventricular pacing, an ECG parameter easily obtainable during LV lead placement, is an independent predictor of mortality in a long-term follow-up. Our data add further evidence that NICM and lower NYHA class are independent predictors for better outcome after CRT implantation.

Impact of Guidelines on the Diffusion of Medical Technology: A Case Study of Cardiac Resynchronization Therapy in the UK

INTRODUCTION

Research on clinical practice guidelines as a determinant of the diffusion of medical technology remains sparse. We aim to evaluate the impact of guidelines on the awareness of medical technology, as a proxy of its use, with the example of cardiac resynchronization therapy (CRT) in the United Kingdom (UK).

METHODS

We measured clinician awareness based on Google searches performed for CRT that corresponded with actual CRT implant numbers provided by the European Heart Rhythm Association (EHRA). We identified the guideline recommendations published by the National Institute of Health and Care Excellence (NICE) within the UK, the European Society of Cardiology (ESC) at the European level, and the American College of Cardiology Foundation/American Heart Association in the United States (US). We specified a dynamic moving average model, with Google searches as the dependent variable and guideline changes as the independent variables.

RESULTS

One guideline change published by NICE in 2007 and two changes released by the US guidelines in 2005 and 2012 were significantly correlated with the Google searches (p = 0.08, p = 0.02, and p = 0.02, respectively). Guideline changes by the ESC had no significant impact. Changes recommending CRT in place of a conventional pacemaker, in patients with atrial fibrillation, and restricting CRT due to contraindication, remained universally uninfluential.

CONCLUSION

The factors associated with a lack of awareness (as a proxy for technology diffusion) in our case study were: a lack of strong clinical evidence that resulted in the moderate strength of a recommendation, a lack of recognition of any externally published recommendation by NICE, and the frequent release of guidelines with minor changes targeting small patient groups. At least in our case, in the absence of NICE guidelines, the US guidelines received more attention than their non-UK European counterparts, even if the former were released after the latter.

Prognostic impact of coronary chronic total occlusion on recurrences of ventricular tachyarrhythmias and ICD therapies

BACKGROUND

Despite a few studies evaluating the prognostic impact of coronary chronic total occlusion (CTO) in implantable cardioverter defibrillator (ICD) recipients, the impact of CTO on different types of recurrences of ventricular tachyarrhythmias, as well as their predictors has not yet been investigated in CTO patients.

METHODS

A large retrospective registry was used including all consecutive patients with ventricular tachyarrhythmias undergoing coronary angiography at index from 2002 to 2016. Only ICD recipients with CTO were compared to patients without (non-CTO). Kaplan-Meier and Cox regression analyses were applied for the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years. Secondary end points comprised of the different types of recurrences, first appropriate ICD therapy and all-cause mortality at 5 years.

RESULTS

From a total of 422 consecutive ICD recipients with ventricular tachyarrhythmias at index, at least one CTO was present in 25%. CTO was associated with the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years (55% vs. 39%; log rank p = 0.001; HR = 1.665; 95% CI 1.221-2.271; p = 0.001), as well as increased risk of first appropriate ICD therapy (40% vs. 31%; log rank p = 0.039; HR = 1.454; 95% CI 1.016-2.079; p = 0.041) and all-cause mortality at 5 years (26% vs. 16%; log rank p = 0.011; HR = 1.797; 95% CI 1.133-2.850; p = 0.013). Less developed collaterals (i.e., either ipsi- or contralateral compared to bilateral) and a J-CTO score ≥ 3 were strongest predictors of recurrences in CTO patients at 5 years.

CONCLUSION

A coronary CTO even in the presence of less developed collaterals and more complex CTO category is associated with increasing risk of recurrent ventricular tachyarrhythmias at 5 years in consecutive ICD recipients.

Rhythm Control in Heart Failure Patients with Atrial Fibrillation

AF and heart failure (HF) commonly coexist. Left atrial ablation is an effective treatment to maintain sinus rhythm (SR) in patients with AF. Recent evidence suggests that the use of ablation for AF in patients with HF is associated with an improved left ventricular ejection fraction and lower death and HF hospitalisation rates. We performed a systematic search of world literature to analyse the association in more detail and to assess the utility of AF ablation as a non-pharmacological tool in the treatment of patients with concomitant HF.

Organ Donor Cards in Resuscitation Room Patients

BACKGROUND

The percentage of organ donors among the German population is very low, and the supply of organs does not meet the demand. Relatively few organ explantations are performed in Germany, compared to other countries. The central element leading up to organ explantation is the donor's consent. This can be expressed either orally or in writing, in the form of an advance directive or organ donor card. The goal of this study was to find out how many patients in hospital resuscitation rooms had organ donor cards on their person.

METHODS

The study population encompassed all 2044 patients treated in the trauma surgery resuscitation room at the Essen University Hospital from 1 February 2017 to 31 March 2019. The data were retrieved from protocols of patient possessions made on admission. The measures taken to enhance data quality were sensitization of the documenting nursing staff and documentation by the first author himself. The literature led us to expect a card-carrier rate of 36%.

RESULTS

Over the entire period of the study, 17 organ donor cards were found (0.8%; 95% confidence interval, [0.5; 1.3]). The figures in all patient subgroups were markedly below the expected 36%. The low rate of carrying organ donor cards could not be explained by a poor quality of documentation.

CONCLUSION

The organ donor card system as it currently exists in Germany is inadequate. These cards are not carried in the emergency situations for which they were developed.

Non-ischemic compared to ischemic cardiomyopathy is associated with increasing recurrent ventricular tachyarrhythmias and ICD-related therapies

OBJECTIVE

The study sought to assess the impact of ischemic (ICMP) compared to non-ischemic cardiomyopathy (NICMP) on recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator (ICD) recipients.

BACKGROUND

Data comparing recurrences of ventricular tachyarrhythmias in ICD recipients with ischemic or non-ischemic cardiomyopathy is limited.

METHODS

A large retrospective registry was used including all consecutive ICD recipients with first episodes of ventricular tachycardia (VT) or fibrillation (VF) from 2002 to 2016. Patients with ICMP were compared to patients with NICMP. The primary prognostic endpoint was first recurrences of ventricular tachyarrhythmias at one year. Secondary endpoints comprised ICD-related therapies, rehospitalization and all-cause mortality at one year. Statistics Kaplan-Meier survival and multivariable Cox regression analyses.

RESULTS

A total of 387 consecutive ICD recipients were included retrospectively (ICMP: 82%, NICMP: 18%). At one year of follow-up, freedom from first recurrences of ventricular tachyarrhythmias was lower in NICMP (81% vs. 71%, log-rank p = 0.063; HR = 1.760; 95% CI 0.985-3.002; p = 0.080), mainly attributed to higher rates of sustained VT (20% versus 12%, p = 0.054). Accordingly, freedom from first appropriate device therapies was lower in NICMP (74% vs. 85%, log rank p = 0.004; HR = 1.951; 95% CI 1.121-3.397; p = 0.028), especially in patients with sustained VT or VF at index. Both groups revealed comparable rates of rehospitalization and all-cause mortality at one year.

CONCLUSION

NICMP was associated with higher rates of recurrent ventricular tachyarrhythmias and appropriate ICD therapies compared to ICMP at one year of follow-up, whereas rates of rehospitalization and all-cause mortality were comparable.

CONDENSED ABSTRACT

This study retrospectively compared the impact of cardiomyopathy types (ICMP versus NICMP) on recurrences of ventricular tachyarrhythmias in 387 ICD recipients. Freedom from first episodes of ventricular tachyarrhythmias and first appropriate device therapies were lower in patients with NICMP compared to ICMP.

Optimisation of cardiac resynchronisation therapy device selection guided by cardiac magnetic resonance imaging: Cost-effectiveness analysis

BACKGROUND

A recent study showed that the presence and characteristics of myocardial scar could independently predict appropriate implantable cardioverter-defibrillator therapies and the risk of sudden cardiac death in patients receiving a de novo cardiac resynchronisation device.

DESIGN

The aim was to evaluate the cost-effectiveness of cardiac magnetic resonance imaging-based algorithms versus clinical practice in the decision-making process for the implantation of a cardiac resynchronisation device pacemaker versus cardiac resynchronisation device implantable cardioverter-defibrillator device in heart failure patients with indication for cardiac resynchronisation therapy.

METHODS

An incidental Markov model was developed to simulate the lifetime progression of a heart failure patient cohort. Key health variables included in the model were New York Heart Association functional class, hospitalisations, sudden cardiac death and total mortality. The analysis was done from the healthcare system perspective. Costs (€2017), survival and quality-adjusted life years were assessed.

RESULTS

At 5-year follow-up, algorithm I reduced mortality by 39% in patients with a cardiac resynchronisation device pacemaker who were underprotected due to misclassification by clinical protocol. This approach had the highest quality-adjusted life years (algorithm I 3.257 quality-adjusted life years; algorithm II 3.196 quality-adjusted life years; clinical protocol 3.167 quality-adjusted life years) and the lowest lifetime costs per patient (€20,960, €22,319 and €28,447, respectively). Algorithm I would improve results for three subgroups: non-ischaemic, New York Heart Association class III-IV and ≥65 years old. Furthermore, implementing this approach could generate an estimated €702 million in health system savings annually in European Society of Cardiology countries.

CONCLUSION

The application of cardiac magnetic resonance imaging-based algorithms could improve survival and quality-adjusted life years at a lower cost than current clinical practice (dominant strategy) used for assigning cardiac resynchronisation device pacemakers and cardiac resynchronisation device implantable cardioverter-defibrillators to heart failure patients.

Increasing age is associated with recurrent ventricular tachyarrhythmias and appropriate ICD therapies secondary to documented index ventricular tachyarrhythmias

BACKGROUND

Data regarding the prognostic impact of age in implantable cardioverter defibrillator (ICD) recipients is limited.

OBJECTIVE

The study sought to assess the impact of age on recurrences of ventricular tachyarrhythmias in ICD recipients.

METHODS

This "secondary prevention" study is based on a large retrospective registry including consecutive ICD recipients with documented ventricular tachyarrhythmias from 2002 to 2016. Patients < 75 years of age were compared to patients ≥ 75 years. The primary endpoint was first recurrence of ventricular tachyarrhythmias at 5 years. Secondary endpoints were ICD-related therapies, rehospitalization, and all-cause mortality at 5 years. Statistics comprised Kaplan-Meier survival curves, multivariable Cox regression analyses, and propensity-score matching.

RESULTS

A total of 592 consecutive ICD recipients with index ventricular tachyarrhythmias was included (< 75 years: 78%; ≥ 75 years 22%). Age ≥ 75 years was associated with the primary endpoint of first recurrence of ventricular tachyarrhythmias (49% vs. 43%, log-rank p = 0.015; HR 1.418; 95% CI 1.070-1.881; p = 0.015), and with the secondary endpoint of first appropriate ICD therapy (78% vs. 22%, log-rank p = 0.011) even within multivariable Cox regression analyses. After propensity-score matching, age ≥ 75 years was still associated with the primary endpoint of first recurrence of ventricular tachyarrhythmias (49% vs. 42%, log-rank p = 0.045; HR 1.482; 95% CI 1.007-2.182; p = 0.046).

CONCLUSION

Elderly ICD recipients aged ≥ 75 years are at increased risk of recurrent ventricular tachyarrhythmias, appropriate ICD therapies, and all-cause mortality at 5 years.

Digitalis Therapy and Risk of Recurrent Ventricular Tachyarrhythmias and ICD Therapies in Atrial Fibrillation and Heart Failure

OBJECTIVE

This study sought to assess the impact of treatment with digitalis on recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator (ICD) recipients with atrial fibrillation (AF) and heart failure (HF).

BACKGROUND

The data regarding outcomes of digitalis therapy in ICD recipients are limited.

METHODS

A large retrospective registry was used, including consecutive ICD recipients with episodes of ventricular tachyarrhythmia between 2002 and 2016. Patients treated with digitalis were compared to patients without digitalis treatment. The primary prognostic outcome was first recurrence of ventricular tachyarrhythmia at 5 years. Kaplan-Meier and multivariable Cox regression analyses were applied.

RESULTS

A total of 394 ICD recipients with AF and/or HF was included (26% with digitalis treatment and 74% without). Digitalis treatment was associated with decreased freedom from recurrent ventricular tachy-arrhythmias (HR = 1.423; 95% CI 1.047-1.934; p = 0.023). Accordingly, digitalis treatment was associated with decreased freedom from appropriate ICD therapies (HR = 1.622; 95% CI 1.166-2.256; p = 0.004) and, moreover, higher rates of rehospitalization (38 vs. 21%; p = 0.001) and all-cause mortality (33 vs. 20%; p = 0.011).

CONCLUSION

Among ICD recipients suffering from AF and HF, treatment with digitalis was associated with increased rates of recurrent ventricular tachyarrhythmias and ICD therapies. However, the endpoints may also have been driven by interactions between digitalis, AF, and HF.

Prognostic impact of recurrences of ventricular tachyarrhythmias and appropriate ICD therapies in a high-risk ICD population

PURPOSE

The study sought to evaluate the prognostic impact of recurrences of ventricular tachyarrhythmias in consecutive ICD recipients with ventricular tachyarrhythmias on admission.

METHODS

All consecutive patients surviving at least one episode of ventricular tachyarrhythmias from 2002 to 2016 and discharged with an ICD (pre-existing ICD or ICD implantation at index hospitalization) were included. The primary endpoint was all-cause mortality according to the presence or absence of recurrences of ventricular tachyarrhythmias at 5 years. Secondary endpoints comprised the impact of different types of recurrences, appropriate ICD therapies, as well as predictors of recurrences and appropriate ICD therapies. Kaplan-Meier, multivariable Cox regression and propensity score matching analyses were applied.

RESULTS

A total of 592 consecutive ICD recipients was included (44% with recurrences of ventricular tachyarrhythmias and 56% without). Recurrences of ventricular tachyarrhythmias were associated with increased all-cause mortality at 5 years (HR = 1.498; 95% CI = 1.052-2.132; p = 0.025). Worst survival was observed in patients with sustained VT or VF as first recurrences compared to non-sustained VT, as well as in patients with cumulative recurrences of non-sustained or sustained VT plus VF, whereas mortality was not affected by the number of recurrences of ventricular tachyarrhythmias (> 4 vs. ≤ 4). Moreover, appropriate ICD therapies were associated with increased all-cause mortality (HR = 1.874; 95% CI = 1.318-2.666; p = 0.001), mainly attributed to secondary preventive ICDs. Finally, atrial fibrillation, LVEF < 35% and non-ischemic cardiomyopathy were identified as predictors of recurrences of ventricular tachyarrhythmias and appropriate ICD therapies.

CONCLUSIONS

Recurrences of ventricular tachyarrhythmias and recurrent appropriate ICD therapies are associated with increased long-term all-cause mortality in consecutive ICD recipients. Non-ischemic cardiomyopathy, AF and LVEF < 35% revealed to be significant predictors of both endpoints.

Biventricular pacing for treating heart failure in children: A case report and review of the literature

BACKGROUND

Cardiac resynchronization therapy (CRT) can be used as an escalated therapy to improve heart function in patients with cardiac dysfunction due to long-term right ventricular pacing. However, guidelines are only targeted at adults. CRT is rarely used in children.

CASE SUMMARY

This case aimed to implement biventricular pacing in one child with heart failure who had a left ventricular ejection fraction < 35% at 4 years after implantation of an atrioventricular sequential pacemaker due to atrioventricular block. Postoperatively, echocardiography showed atrial sensing ventricular pacing and QRS wave duration of 120-130 ms, and cardiac function significantly improved after upgrading pacemaker.

CONCLUSION

Patients whose cardiac function is deteriorated to a level to upgrade to CRT should be upgraded to reverse myocardial remodeling as soon as possible.

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

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

Risk factor paradox: No prognostic impact of arterial hypertension and smoking in patients with ventricular tachyarrhythmias

BACKGROUND

Data regarding the outcome of patients with ventricular tachyarrhythmias related to arterial hypertension (AHT) and smoking is limited. The study sought to assess the prognostic impact of AHT and smoking on survival in patients presenting with ventricular tachyarrhythmias.

METHODS

All consecutive patients surviving ventricular tachycardia (VT) and ventricular fibrillation (VF) upon admission to the University Medical Center Mannheim (UMM), Germany from 2002 to 2016 were included and stratified according to AHT and smoking by propensity score matching. The primary prognostic endpoint was all-cause mortality at 30 months.

RESULTS

A total of 988 AHT-matched patients (494 each, with and without AHT) and a total of 872 smoking-matched patients (436 each, with and without smoking) were included. The rates of VT and VF were similar in both groups (VT: AHT 60% vs. no AHT 60%; smokers 61% vs. non-smokers 62%; VF: AHT 35% vs. no AHT 38%; smokers 39% vs. non-smokers 38%). Neither AHT nor smoking were associated with the primary endpoint of long-term all-cause mortality at 30 months (long-term mortality rates: AHT/no AHT, 26% vs. 28%; log-rank p = 0.525; smoking/non-smoking, 22% vs. 25%; log-rank p = 0.683).

CONCLUSIONS

Paradoxically, neither AHT nor smoking were associated with differences of long-term all-cause mortality in patients presenting with ventricular tachyarrhythmias.

Comparison of Long-Term Clinical Implications of Beta-Blockade in Patients With Obstructive Airway Diseases Exposed to Beta-Blockers With Different β1-Adrenoreceptor Selectivity: An Italian Population-Based Cohort Study

Rationale: Long-term clinical implications of beta-blockade in obstructive airway diseases remains controversial. We investigated if within the first 5 years of treatment patients with heart failure and obstructive airway diseases using non β1-adrenoreceptor selective beta-blockers have an increased risk of being hospitalized for all-causes, heart failure, and chronic obstructive pulmonary disease (COPD) when compared to patient using selective beta-blockers.

Methods: Carvedilol users were propensity matched 1:1 for co-treatments, age, gender, and year of inclusion in the cohort with metoprolol/bisoprolol/nebivolol users. Cox proportional hazard regression model was used to compare all causes, COPD, and heart failure hospitalization or the beta-blocker discontinuation between cohorts. For statistically significant associations, we computed the rate difference and the attributable risk.

Results: Overall, 11,844 patients out of the 51,214 (23.1%) were exposed to carvedilol and 39,370 (76.9%) to metoprolol/bisoprolol/nebivolol. Carvedilol users had a higher hazard for heart failure hospitalization (HR 1.29; 95% Confidence Interval [CI] 1.18–1.40) with 106 (95%CI 76–134; p-value < 0.001) additional cases of heart failure hospitalization per 10000 person-years if compared to metoprolol/bisoprolol/nebivolol users. In all, 26.8% (95%CI 22.5–30.9%; p-value < 0.001) of heart failure hospitalizations in the study population could be attributed to being exposed to carvedilol. Carvedilol users had a higher hazard (HR 1.06; 95%CI 1.02–1.10) of discontinuing the pharmacological treatment with 131 (95%CI 62–201; p-value < 0.001) additional cases of beta-blocker discontinuation per 10000 person-years metoprolol/bisoprolol/nebivolol users. In all, 6.5% (95%CI 3.9–9.0%; p-value < 0.001) of beta-blocker discontinuation could be attributed to being exposed to carvedilol.

Conclusion: On long-term follow-up period, carvedilol was associated with a higher risk of heart failure hospitalization and discontinuation if compared to metoprolol/bisoprolol/nebivolol users among patients with heart failure and obstructive airway diseases.

Upgrade to his bundle pacing in pacing-dependent patients referred for pulse generator change: Feasibility and intermediate term follow up

BACKGROUND

Right ventricular pacing (RVP) is associated with an increased incidence of heart failure and may impair cardiac function. Permanent His bundle pacing (HBP) has the potential to physiologically preserve and prevent cardiac dysfunction. This study was to evaluate the feasibility and intermediate follow-up results of upgrade to HBP implantation in patients referred for pulse generator change with long term RVP.

METHODS

Twelve of 14 pacing dependent patients who were referred for pulse generator exchange underwent upgrade into HBP successfully in our center. QRS duration, New York Heart Association (NYHA) functional class, echocardiography, use of diuretics and lead parameters were measured at baseline and during the follow-up.

RESULTS

Among the 12 patients attempted (mean age, 70.8 ± 8.9 years, 75% males) successfully, the average ejection fraction (EF) was 52.2 ± 11.2%. Nine of 12 patients underwent upgrade to HBP, and three patients with EF < 40% underwent HBP and biventricular pacing (BVP) as well. A significant reduction in mean QRS duration was observed compared with pre-implantation, from 157.8 ± 13.3 ms to 109.3 ± 16.9 ms (p < 0.001). After 6 months follow-up period, median NYHA functional class was improved from 2.7 ± 0.6 to 1.8 ± 0.6 (p = 0.007) and left ventricular internal diastolic diameter (LVIDd) was reduced from 5.5 ± 0.4 cm to 5.3 ± 0.3 cm (p = 0.03).

CONCLUSIONS

HBP improves heart failure symptoms with preserved EF by long term RVP. Permanent HBP is feasible and safe for upgrade in patients with long term RVP irrespective of LVEF.

Left bundle branch block and the evolving role of QRS morphology in selection of patients for cardiac resynchronization

BACKGROUND

The clinical significance of left bundle branch block (LBBB) has recently expanded with the discovery of a strong association with better outcomes in patients receiving cardiac resynchronization therapy.

METHODS

Several milestones have contributed to the current understanding on the role of LBBB in clinical practice.

RESULT

Sunao Tawara described the arrangement of components of what he called the cardiac conduction system from the atrioventricular node to the terminal Purkinje fibers that connect to the working myocardium, and his hypotheses on how it functions remain current. Mauricio Rosenbaum and colleagues developed the bifascicular model of the left-sided conduction system that explains the characteristic electrocardiographic changes associated with propagation disturbances in its components. Andrés Ricardo Pérez-Riera and others have disputed the bifascicular model as oversimplified and have emphasized the role of the left septal fascicle. Marcelo Elizari and colleagues have explained the importance of masquerading bundle branch block. Elena Sgarbossa and colleagues developed a scheme to recognize ST elevation myocardial infarction in patients with left bundle branch block which remains current after more than 20 years. Enrique Cabrera and others identified electrocardiographic signs of remote myocardial infarction.

CONCLUSION

Substantial progress has been made in the understanding of LBBB, yet its role in clinical practice continues to evolve and important gaps remain to which research should be directed.

Long-term outcomes after event-free cardioverter defibrillator implantation: comparison between patients discharged within 24 h and routinely hospitalized patients in the German DEVICE registry

Aims

To analyse the long-term safety of implantable cardioverter defibrillators (ICDs) in patients discharged within 24 h or after 2- 5-day hospitalization, respectively, after complication-free implantation, in circumstances of actual care.

Methods and results

Patients in the multicentre, nationwide German DEVICE registry were contacted 12-15 months after their first ICD implantation or device replacement. Data were collected on complications, potential arrhythmic events, syncope, resuscitation, ablation procedures, cardiac events, hospitalizations, heart failure status, change of medication, and quality of life. Of 2356 patients from 43 centres, 527 patients were discharged within 24 h and 1829 were hospitalized routinely for >24 h after complication-free implantations. The disease profiles and rates of co-morbidities were similar at baseline for both cohorts. During between 384 and 543 days of follow-up, there were no significant differences between the groups in terms of complications, hospitalizations, or quality of life. One-year rates of death were 4.5% in patients discharged early compared with 7.2% in hospitalized patients (hazard ratio 0.65; 95% confidence interval 0.42-1.02; P = 0.052). Rates of major adverse cardiovascular events or defibrillator events were not higher in patients discharged after 24 h. In both groups, a high rate of patients declared that they would opt for the procedure again in the same situation.

Conclusion

Data from a large-scale registry reflecting current day-to-day practice in Germany suggest that most patients can be discharged safely within 24 h of successful ICD implantation if there are no procedure-related events. Follow-up data up to 1.5 years after implantation did not raise long-term safety concerns.

Potential benefit of optimizing atrioventricular & interventricular delays in patients with cardiac resynchronization therapy

Background & objectives:

The clinical benefit of optimization (OPT) of atrioventricular delay (AVD) and interventricular delay (VVD) in cardiac resynchronization therapy (CRT) remains debatable. This study was aimed to determine the influence of AVD and VVD OPT on selected parameters in patients early after CRT implantation and at mid-term follow up (FU).

Methods:

Fifty two patients (61±10 yr, 23 males) with left bundle branch block, left ventricular ejection fraction (LVEF) ≤35 per cent and heart failure were selected for CRT implantation. Early on the second day (2DFU) after CRT implantation, the patients were assigned to the OPT or the factory setting (FS) group. Haemodynamic and electrical parameters were evaluated at baseline, on 2DFU after CRT and mid-term FU [three-month FU (3MFU)]. Echocardiographic measures were assessed before implantation and at 3MFU. The AVD/VVD was deemed optimal for the highest cardiac output (CO) with impedance cardiography (ICG) monitoring.

Results:

On 2DFU, the AVD was shorter in the OPT group, LV was paced earlier than in FS group and CO was insignificantly higher in OPT group. At 3MFU, improvement of CO was observed only in OPT patients, but the intergroup difference was not significant. At 3MFU in OPT group, reduction of LV in terms of LV end-diastolic diameter (LVeDD), LV end-systolic diameter, LV end-diastolic and systolic volume with the improvement in LVEF was observed. In FS group, only a reduction in LVeDD was present. In OPT group, the paced QRS duration was shorter than in FS group patients.

Interpretation & conclusions:

CRT OPT of AVD and VVD with ICG was associated with a higher CO and better reverse LV remodelling. CO monitoring with ICG is a simple, non-invasive tool to optimize CRT devices.

Advances in Cardiovascular Health in Women over the Past Decade: Guideline Recommendations for Practice

Cardiovascular disease (CVD) remains the number one cause of death in women. It is estimated that 44 million women in the United States are either living with or at risk for heart disease. This article highlights the recent significant progress made in improving care, clinical decision-making, and policy implications for women with CVD. We provide our perspective supported by evidence-based advances in cardiovascular research and clinical care guidelines in seven areas: (1) primary CVD prevention and community heart care, (2) secondary prevention of CVD, (3) stroke, (4) heart failure and cardiomyopathies, (5) ischemia with nonobstructive coronary artery disease, (6) spontaneous coronary artery dissection, and (7) arrhythmias and device therapies. Advances in these fields have improved the lives of women living with and at risk for heart disease. With increase awareness, partnership with national organizations, sex-specific research, and changes in policy, the morbidity and mortality of CVD in women can be further reduced.

Effect of expanding evidence and evolving clinical guidelines on the prevalence of indication for cardiac resynchronization therapy in patients with heart failure

AIMS

To assess the prevalence of indication for cardiac resynchronization therapy (CRT) in patients with heart failure (HF) and reduced ejection fraction (EF) when recommendations from evolving European Society of Cardiology (ESC) guidelines are considered.

METHODS AND RESULTS

Unique patients (n=17 193) with EF ≤39% and key data available for evaluation of CRT indication from the Swedish HF Registry were included. Indication for CRT was defined as either CRT implanted or CRT device absent but fulfilling criteria for class I-IIa recommendations in ESC guidelines published between 2005/2007 and 2016. Prevalence was calculated as the ratio of patients with CRT indication to the study population. The prevalence of CRT indication increased from 24.5% when the 2005/2007 ESC guidelines were considered to a peak of 30.0% when the 2013 ESC guidelines were considered (P<0.001, 22.4% relative increase). Compared to the 2013 ESC guidelines, the prevalence declined significantly when the 2016 ESC guidelines were used as determinant for CRT indication (26.8%, 10.7% relative reduction, P<0.001). Actual CRT utilization was 6.8%.

CONCLUSION

Among patients with HF and reduced EF, the prevalence of CRT indication increased significantly comparing recommendations from ESC guidelines published between 2005/2007 and 2013, but then declined when the 2016 ESC guidelines were considered. The 2005-2013 increase may reflect the expansion of documented CRT efficacy to New York Heart Association class II, whereas the subsequent drop likely results from the more stringent criteria for QRS duration in the 2016 ESC guidelines. Actual CRT utilization is lower than indicated, regardless of which guidelines are considered.

Effect of fixed-rate vs. rate-RESPONSIve pacing on exercise capacity in patients with permanent, refractory atrial fibrillation and left ventricular dysfunction treated with atrioventricular junction aBLation and bivEntricular pacing (RESPONSIBLE): a prospective, multicentre, randomized, single-blind study

Aims

Atrioventricular junction (AVJ) ablation followed by biventricular pacing is an established strategy for improving symptoms and morbidity in patients with permanent atrial fibrillation (AF), reduced left ventricular ejection fraction (LVEF), and uncontrolled ventricular rate. There is no clear evidence that such patients benefit from rate-responsive (RR) pacing.

Methods and results

This prospective, randomized, single-blind, multicentre study was designed as an intra-patient comparison and enrolled 60 patients (age 69.5 ± 11.8 years, males 63.3%, NYHA 3.0 ± 0.6) with refractory AF and reduced LVEF (mean 32.4 ± 8.3%) treated with AVJ ablation and biventricular pacing. Two 6-minute walking tests (6MWT) were performed 1 week apart: one during VVI 70/min biventricular pacing and the other during VVIR 70-130/min biventricular pacing; patients were randomly and blindly assigned to Group A (n = 29, first 6MWT in VVIR mode) or B (n = 31, first 6MWT in VVI mode). Rate-responsive activation determined an increase of 18.8 ± 24.4 m in the distance walked during the 6MWT (P < 0.001). The increase was similar in both groups (P = 0.571). A >5% increase in the distance walked was observed in 76.7% of patients. The increase in the distance walked was linearly correlated with the increase in heart rate recorded during the 6MWT in the VVIR mode (r = 0.54; P < 0.001).

Conclusion

In permanent AF patients with uncontrolled rate and reduced LVEF who had undergone AVJ ablation and biventricular pacing, RR pacing yields a significant gain in exercise capacity, which seems to be related to the RR-induced frequency during effort.

Detection and discrimination of tachycardia in ICDs manufactured by St. Jude Medical

Modern implantable cardioverter/defibrillator (ICD) systems offer a multitude of algorithms to optimize performance in sensing and tachycardia detection even in difficult circumstances (e. g., ventricular tachycardia during supraventricular tachycardia, fine ventricular fibrillation with intermittent undersensing), to reliably discriminate sustained ventricular tachyarrhythmia from noise, nonsustained and supraventricular tachyarrhythmia, and to limit shock therapy only to those arrhythmias that definitely need to be treated by a shock. A disadvantage of these multiple algorithms is the complexity of annotated tracings that makes it sometimes difficult to understand why the ICD did what it did. If a tachycardia classification was wrong, it may be thus difficult to find the best way to reprogram the device to avoid another misclassification. This review explains in detail the algorithms used for tachycardia detection, discrimination, and prevention of inappropriate therapy in single- and dual-chamber ICDs manufactured by St. Jude Medical. Knowledge of these features may help to optimize ICD treatment in patients fitted with these devices.

Magnitude of QRS duration reduction after biventricular pacing identifies responders to cardiac resynchronization therapy

BACKGROUND

Several studies have investigated the association between native QRS duration (QRSd) or QRS narrowing and response to biventricular pacing. However, their results have been conflicting. The aim of our study was to determine the association between the relative change in QRS narrowing index (QI) and clinical outcome and prognosis in patients who undergo cardiac resynchronization therapy (CRT) implantation.

METHODS AND RESULTS

We included 311 patients in whom a CRT device was implanted in accordance with current guidelines for CRT. On implantation, the native QRS, the QRSd and the QI during CRT were measured. After 6months, 220 (71%) patients showed a 10% reduction in LVESV. The median [25th-75th] QI was 14.3% [7.2-21.4] and was significantly related to reverse remodeling (r=+0.22; 95%CI: 0.11-0.32, p=0.0001). The cut-off value of QI that best predicted LV reverse remodeling after 6months of CRT was 12.5% (sensitivity=63.6%, specificity=57.1%, area under the curve=0.633, p=0.0002). The time to the event death or cardiovascular hospitalization was significantly longer among patients with QI>12.5% (log-rank test, p=0.0155), with a hazard ratio (HR) of 0.3 [95%CI: 0.11-0.78]. In the multivariate regression model adjusted for baseline parameters, a 10% increment in QI (HR=0.61[0.44-0.83], p=0.002) remained significantly associated with CRT response.

CONCLUSIONS

Patients with a larger decrease in QRSd after CRT initiation showed greater echocardiographic reverse remodeling and better outcome from death or cardiovascular hospitalization. QI is an easy-to-measure variable that could be used to predict CRT response at the time of pacing site selection or pacing configuration programming.

A survey of views and opinions of health professionals managing thirst in chronic heart failure

BACKGROUND

Thirst is a common and burdensome symptom of chronic heart failure (CHF) which affects adherence to self-care practices specifically fluid restriction. Despite this, there is no standard clinical practice for managing the symptom of thirst.

AIMS AND OBJECTIVES

The aim is to identify the current strategies recommended by health professionals to help relieve thirst in CHF patients and their perceived usefulness of these strategies.

METHODS

A survey was distributed to attendees of the 8th Annual Scientific Meeting of Australasian Cardiovascular Nursing College.

RESULTS

There were 42 of 70 respondents to the survey. The majority (33 of 40; 82.5%) had recommended various strategies to alleviate thirst. The most recommended strategy was ice chips (36 of 38; 94.7%). Overall, the respondents reported 'some use' in all of the strategies.

CONCLUSION

Information from this survey may help in the incorporation of thirst-relieving strategies into evidence-based guidelines; further improving the quality of care of patients.

Why QRS Duration Should Be Replaced by Better Measures of Electrical Activation to Improve Patient Selection for Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) is a well-known treatment modality for patients with a reduced left ventricular ejection fraction accompanied by a ventricular conduction delay. However, a large proportion of patients does not benefit from this therapy. Better patient selection may importantly reduce the number of non-responders. Here, we review the strengths and weaknesses of the electrocardiogram (ECG) markers currently being used in guidelines for patient selection, e.g., QRS duration and morphology. We shed light on the current knowledge on the underlying electrical substrate and the mechanism of action of CRT. Finally, we discuss potentially better ECG-based biomarkers for CRT candidate selection, of which the vectorcardiogram may have high potential.

[Device therapy of chronic heart failure: Update 2015]

Cardiac pacemakers, implantable cardioverter defibrillators (ICD) and systems for cardiac resynchronization therapy (CRT) represent an important component of heart failure therapy. Pacemakers only play a role in bradycardia-associated heart failure and require optimal programming to prevent ventricular desynchronization. Primary prophylactic ICD implantation is indicated in patients with a left ventricular ejection fraction of ≤ 35 %, clinical stages NYHA II-III and a life expectancy > 1 year. The CRT is indicated in patients with a left bundle branch block but only in individual cases for other QRS morphologies of < 150 ms duration. The combination of CRT with a pacemaker or defibrillator must be decided on an individual basis. Device therapy in heart failure should always include remote monitoring to detect events early and to implement treatment accordingly. New developments include quadripolar left ventricular leads and pacing from multiple sites simultaneously thus enabling better resynchronization. Stimulation for modulation of cardiac contractility and the autonomous nervous system are currently being clinically tested. The optimal utilization of device therapy improves the course of heart failure and prevents cardiac decompensation and fatalities.

Atrioventricular and ventricular-to-ventricular programming in patients with cardiac resynchronization therapy: results from ALTITUDE

PURPOSE

Cardiac resynchronization therapy (CRT) improves outcomes in patients with heart failure, yet response rates are variable. We sought to determine whether physician-specified CRT programming was associated with improved outcomes.

METHODS

Using data from the ALTITUDE remote follow-up cohort, we examined sensed atrioventricular (AV) and ventricular-to-ventricular (VV) programming and their associated outcomes in patients with de novo CRT from 2009-2010. Outcomes included arrhythmia burden, left ventricular (LV) pacing, and all-cause mortality at 4 years.

RESULTS

We identified 5709 patients with de novo CRT devices; at the time of implant, 34% (n = 1959) had entirely nominal settings programmed, 40% (n = 2294) had only AV timing adjusted, 11% (n = 604) had only VV timing adjusted, and 15% (n = 852) had both AV and VV adjusted from nominal programming. Suboptimal LV pacing (<95%) during follow-up was similar across groups; however, the proportion with atrial fibrillation (AF) burden >5% was lowest in the AV-only adjusted group (17.9%) and highest in the nominal (27.7%) and VV-only adjusted (28.3%) groups. Adjusted all-cause mortality was significantly higher among patients with non-nominal AV delay >120 vs. <120 ms (adjusted heart rate (HR) 1.28, p = 0.008) but similar when using the 180-ms cutoff (adjusted HR 1.13 for >180 vs. ≤180 ms, p = 0.4).

CONCLUSIONS

Nominal settings for de novo CRT implants are frequently altered, most commonly the AV delay. There is wide variability in reprogramming. Patients with nominal or AV-only adjustments appear to have favorable pacing and arrhythmia outcomes. Sensed AV delays less than 120 ms are associated with improved survival.

Echocardiographic assessment of right ventricular function in responders and non-responders to cardiac resynchronization therapy

INTRODUCTION

The aim of this study was to determine whether baseline right ventricular (RV) function assessed by standard echocardiography may indicate patients who will respond to cardiac resynchronization therapy (CRT).

MATERIAL AND METHODS

The data of 57 patients (54 men, 95%), aged 66.4 ±8.7 years with heart failure (HF) having a CRT device implanted were collected. All patients had left ventricular ejection fraction (LVEF) ≤ 35% and QRS complex duration ≥ 120 ms. Echocardiographic examination with tissue Doppler imaging techniques and complex RV evaluation were performed at baseline and three months after CRT onset.

RESULTS

Three months after CRT implantation, patients responding to CRT, defined as a reduction of left ventricle end-systolic volume (LVESV) of at least 10% (n = 34), compared to patients with a reduction of LVESV of less than 10% (n = 23), had at baseline a smaller right atrium diameter (47.85 ±11.33 mm vs. 52.65 ±8.69 mm; p = 0.028), higher TAPSE (14.56 ±2.57 mm vs. 13.04 ±2.93 mm; p = 0.030) and lower grade of tricuspid valve regurgitation (1.82 ±0.97 vs. 2.3 ±0.88; p = 0.033).

CONCLUSIONS

This study showed that there are differences in baseline right ventricular function between responders and non-responders to CRT. Yet in our study, none of the baseline RV parameters provided any value in identifying patients who would respond to CRT.

First clinical evaluation of an atrial haemodynamic sensor lead for automatic optimization of cardiac resynchronization therapy

AIMS

One option to improve cardiac resynchronization therapy (CRT) responder rates lies in the optimization of pacing intervals. A haemodynamic sensor embedded in the SonRtip atrial lead measures cardiac contractility and provides a systematic automatic atrioventricular and interventricular delays optimization. This multi-centre study evaluated the safety and performance of the lead, up to 1 year.

METHODS AND RESULTS

A total of 99 patients were implanted with the system composed of the lead and a CRT-Defibrillator device. Patients were followed at 1, 3, 6, and 12 months post-implant. The primary safety objective was to demonstrate that the atrial lead complication free rate was superior to 90% at 3-months follow-up visit. A lead handling questionnaire was filled by implanting investigators. Lead electrical performances and the performance of the system to compute AV and VV delays were evaluated at each study visit over 1 year. The complication free rate at 3 months post-implant was 99.0% [95%CI 94.5-100.0%], P < 0.001. Electrical performances of the lead were adequate whatever the atrial lead position and remained stable over the study period. The optimization algorithm was able to compute AV and VV delays in 97% of patients, during >75% of the weeks.

CONCLUSION

The atrial lead is safe to implant and shows stable electrical performance over time. It therefore offers a promising tool for automatic CRT optimization to further improve responder rates to CRT.

Recommendations for cardiomyopathy surveillance for survivors of childhood cancer: a report from the International Late Effects of Childhood Cancer Guideline Harmonization Group

Survivors of childhood cancer treated with anthracycline chemotherapy or chest radiation are at an increased risk of developing congestive heart failure. In this population, congestive heart failure is well recognised as a progressive disorder, with a variable period of asymptomatic cardiomyopathy that precedes signs and symptoms. As a result, several clinical practice guidelines have been developed independently to help with detection and treatment of asymptomatic cardiomyopathy. These guidelines differ with regards to definitions of at-risk populations, surveillance modality and frequency, and recommendations for interventions. Differences between these guidelines could hinder the effective implementation of these recommendations. We report on the results of an international collaboration to harmonise existing cardiomyopathy surveillance recommendations using an evidence-based approach that relied on standardised definitions for outcomes of interest and transparent presentation of the quality of the evidence. The resultant recommendations were graded according to the quality of the evidence and the potential benefit gained from early detection and intervention.

Comparison of pharmacological treatment alone versus treatment combined with cardiac resynchronization therapy in patients over 75 years

BACKGROUND

The role of cardiac resynchronization therapy (CRT) in patients aged ≥75 years is not well established.

METHODS

We identified 607 patients aged ≥75 years with left ventricular ejection fraction (LVEF) of ≤35 %, of whom 78 met the guidelines for indication of CRT. Based on the decision of the patients or attending cardiologists, 34 patients received a CRT defibrillator (CRT-D).

RESULTS

The age of patients with a CRT indication was 80 ± 4 years, and 73 % were males. As compared with patients on medical therapy, CRT-D patients were younger (79 ± 3 vs. 83 ± 4, P < 0.001), had lower LVEF (23 ± 7 vs. 27 ± 7 %, P = 0.008) and higher rate of decompensated heart failure episodes (77 vs. 55 %, P = 0.04), were more frequently New York Heart Association (NYHA) class III-IV (53 vs. 25 %, P = 0.01), and were more likely to be on beta-blockers (88 vs. 66 %, P = 0.023), anticoagulants (61 vs. 32 % P = 0.02), and anti-aldosterone drugs (82 vs. 50 %, P = 0.003). After a median follow-up of 26 months, seven patients in the CRT-D group (21 %) and 20 non-CRT patients (46 %) died (hazard ratio (HR) 0.16 [95 % confidence interval (CI) 0.06-0.46]). The end point of mortality or hospitalization was not reduced because of a similar rate of hospitalizations for heart failure of CRT-D patients. Four CRT-D patients (12 %) had received appropriate device therapy, and one had been inappropriately discharged. During follow-up, 44 % of CRT-D patients improved their LVEF by >40 %.

CONCLUSION

CRT-D is potentially of benefit in terms of mortality in our population; this effect persists after correction for use of beta-blockers. In patients ≥75 years, CRT indications should be similar to those accepted for younger subjects.

Sex- and gender-specific research priorities for the emergency management of heart failure and acute arrhythmia: proceedings from the 2014 Academic Emergency Medicine Consensus Conference Cardiovascular Research Workgroup

The emergency department (ED) is the point of first contact for patients with acute heart failure and arrhythmias, with 1 million annual ED visits in the United States. Although the total numbers of men and women living with heart failure are similar, female patients are underrepresented in clinical studies, with current knowledge predominantly based on data from male patients. This has led to an underappreciation of the sex-specific differences in clinical characteristics and pathophysiology-based management of heart failure. Similar disparities have been found in management of acute arrhythmias, especially atrial arrhythmias that lead to an increased risk of stroke in women. Additionally, peripartum and postpartum cardiomyopathy represent a diagnostic and treatment dilemma. This article is the result of a breakout session in the cardiovascular and resuscitation work group of the 2014 Academic Emergency Medicine consensus conference "Gender-Specific Research in Emergency Medicine: Investigate, Understand, and Translate How Gender Affects Patient Outcomes." A nominal group technique was used to identify and prioritize themes and research questions using electronic mail, monthly conference calls, in-person meetings, and Web-based surveys between June 2013 and May 2014. Consensus was achieved through three rounds of nomination followed by the meeting on May 13, 2014, and resulted in seven priority themes that are essential to the common complex clinical syndrome of heart failure for both men and women and include the areas of pathophysiology; presentation and symptomatology; and diagnostic strategies using biomarkers, treatment, and mortality, with special consideration to arrhythmia management and pregnancy.

Endoplasmic reticulum stress induces different molecular structural alterations in human dilated and ischemic cardiomyopathy

Background

The endoplasmic reticulum (ER) is a multifunctional organelle responsible for the synthesis and folding of proteins as well as for signalling and calcium storage, that has been linked to the contraction-relaxation process. Perturbations of its homeostasis activate a stress response in diseases such as heart failure (HF). To elucidate the alterations in ER molecular components, we analyze the levels of ER stress and structure proteins in human dilated (DCM) and ischemic (ICM) cardiomyopathies, and its relationship with patient's functional status.

Methods and Results

We examined 52 explanted human hearts from DCM (n = 21) and ICM (n = 21) subjects and 10 non-failing hearts as controls. Our results showed specific changes in stress (IRE1, p<0.05; p-IRE1, p<0.05) and structural (Reticulon 1, p<0.01) protein levels. The stress proteins GRP78, XBP1 and ATF6 as well as the structural proteins RRBP1, kinectin, and Nogo A and B, were upregulated in both DCM and ICM patients. Immunofluorescence results were concordant with quantified Western blot levels. Moreover, we show a novel relationship between stress and structural proteins. RRBP1, involved in procollagen synthesis and remodeling, was related with left ventricular function.

Conclusions

In the present study, we report the existence of alterations in ER stress response and shaping proteins. We show a plausible effect of the ER stress on ER structure in a suitable sample of DCM and ICM subjects. Patients with higher values of RRBP1 had worse left ventricular function.

Positive response to cardiac resynchronization therapy reduces arrhythmic events after elective generator change in patients with primary prevention CRT-D

INTRODUCTION

Cardiac resynchronization therapy (CRT) and implantable cardioverter-defibrillators (ICD) are effective therapies for heart failure (HF) patients with cardiac dyssynchrony. Patients receiving primary prevention CRT-defibrillator that positively remodel might no longer qualify for ICD indication due to CRT-induced left ventricular ejection fraction (LVEF) improvement. We aimed to evaluate the outcome of CRT-D patients at the time of device replacement (DR).

METHODS AND RESULTS

Patients undergoing primary prevention CRT-D DR were prospectively included from November 2007 to March 2011 in 2 centers. CRT response was as defined as ≥1 NYHA class improvement and an increase in LVEF ≥10%. Before DR, all patients underwent echocardiography and device interrogation. Patients without theoretical ongoing ICD indication (TOII) at DR were defined as those with LVEF ≥40% without appropriate ICD therapy (appropriate therapy) during the first ICD service-life. A total of 107 consecutive patients were enrolled. Sixty-one patients (57%) were considered CRT responders after the index procedure. At the time of DR (56.4 ± 14.4 months from initial implant), 87% of CRT responders were free of appropriate therapy, compared with 70% of CRT nonresponders (P = 0.02). Thirty-nine patients (37%) did not meet the criteria for TOII. During follow-up (mean 26.4 ± 14.4 months after DR), 37 patients (95%) without TOII were free of appropriate therapy versus 49 of 68 patients (72%) with ongoing TOII (P = 0.007). By multivariable analysis, the only independent predictor of appropriate therapy after DR was TOII (hazard ratio = 6.43; P = 0.01).

CONCLUSION

Absence of theoretical ICD indication occurs in more than one-third of CRT-D patients undergoing DR. In addition, appropriate therapy rate is relatively low (2.2% per year) in this subgroup of patients.

Effects of atrioventricular nodal ablation on permanent atrial fibrillation patients with cardiac resynchronization therapy: a systematic review and meta-analysis

Cardiac resynchronization therapy (CRT) is a well-established therapy for patients with heart failure (HF) and wide QRS configuration, especially for those in sinus rhythm. However, for those with permanent AF, atrioventricular nodal (AVN) ablation use remains under debate. Our objective was to evaluate clinical outcomes and mortality of AVN ablation in HF patients with permanent AF receiving CRT. Electronic publication database and reference lists through October 1, 2013 were searched. Observational cohort studies comparing CRT patients with AF who received either AVN ablation or medical therapy were selected. Outcomes included mortality, CRT nonresponse, changes in left ventricular remodeling, and functional outcomes, such as New York Heart Association (NYHA) functional class, quality of life, and 6-minute hall walk distance. Of 1641 reports identified, 13 studies with 1256 patients were included. Among patients with permanent AF and insufficient biventricular pacing (< 90%), those who had undergone AVN ablation compared to those who did not had numerically lower all-cause mortality (risk ratio [RR]: 0.63, 95% confidence interval [CI]: 0.42 to 0.96, P = 0.03) and significantly lower nonresponse to CRT (RR: 0.41, 95% CI: 0.31 to 0.54, P < 0.00001). Furthermore, AVN ablation was not associated with additional improvements on left ventricular ejection fraction, NYHA functional class, 6-minute hall walking distance, and quality of life. In patients with permanent AF undergoing CRT, AVN ablation tended to reduce mortality potentially and improved clinical response when it was applied to patients with inadequate biventricular pacing (< 90%). Randomized controlled trials are needed to further address the efficacy of AVN ablation among this population.

Ranolazine maintained sinus rhythm in a patient with refractory symptomatic atrial fibrillation

We report on a patient who was treated with several antiarrhythmic drugs as well as different ablation strategies. Nevertheless, symptomatic atrial fibrillation always recurred until an off-label use with ranolazine was started. We could demonstrate potent effects of ranolazine on atrial fibrillation in a "wash-in wash-out" situation. Although promising controlled studies are needed to investigate a potential role of ranolazine for the treatment of atrial fibrillation.