Sudden cardiac death after implantation of a cardiac resynchronization therapy pacemaker: a case report illustrating that not always less is more.

BACKGROUND: Cardiac resynchronization therapy (CRT) improves symptoms and survival in selected patients with systolic heart failure and ventricular conduction delay. In subjects without prior life-threatening ventricular arrhythmia, clinicians have to select between implanting a CRT pacemaker (CRT-P) or a more complex device with additional defibrillator capability (CRT-D). This individual decision can be challenging in light of the available evidence and the potential risks and benefits. CASE SUMMARY: A 76-year-old male with non-ischaemic cardiomyopathy, heart failure New York Heart Association Class III, left bundle branch block (QRS duration 185 ms) and a left ventricular ejection fraction of 30% despite optimal medical therapy was indicated for CRT. In light of the patient characteristics and clinical condition, a CRT-P device was implanted. No complication occurred, and the patient was discharged after an appropriate device function was confirmed. Despite the clinical improvement, he died suddenly without prior symptoms approximately 2 months thereafter. Post-mortem device interrogation provided no evidence for device malfunction and confirmed sudden cardiac death (SCD) due to spontaneous ventricular fibrillation. DISCUSSION: Patients indicated for CRT often have overlapping internal cardioverter defibrillator indication for the primary prevention of SCD. By weighing individual risks and potential benefits, clinicians have to decide whether to implant a CRT-P (less is more) or a more complex and costly CRT-D device. Despite careful consideration of patient characteristics and clinical conditions, however, SCD can occur in subjects categorized as low risk and implanted with a CRT-P. More data from randomized clinical trials are needed to better support physicians in the often challenging process of selecting the most appropriate device for CRT.

[Safety and efficiency of interventional electrophysiology utilizing the German "Belegarztsystem"]. / Effizienz und Sicherheit einer interventionellen Elektrophysiologie im kooperativen Belegarztsystem.

INTRODUCTION: Electrophysiology study (EPS) and catheter ablation (abl.), in particular for atrial fibrillation, are increasingly performed in Germany. Therefore, measures and steps to ensure quality assurance are indicated. Most of the procedures are performed by physicians employed by hospitals; however, some are also carried out by attending cardiologists on contract in private practice, applying the so-called Belegarztsystem. The aim of this study was to determine the safety and efficiency of an interventional electrophysiology performed in a German Belegarztsystem. METHODS: Based on a prospective registry, we analyzed procedure-related data from 1400 consecutive EPS/abl. performed at our center between 2014 and 2018. One-year follow-up data (arrhythmia recurrences, complications, deaths) were collected for all procedures carried out during the first 2 years. RESULTS: In the total study cohort, no periprocedural death occurred, and there was a low cumulative incidence of groin complications (0.9%). The most common procedure (n = 772) was complex ablation for atrial fibrillation/flutter (55%). In this group, the success rate was 98% (acute) and 65% (1 year), and the cumulative rate of complications was 5.0% (transient ischemic attack/stroke 0.1%, pericardial tamponade 0.4%, relevant pericarditis/pericardial effusion 1.1%, groin complication 1.5%, other 1.9%). For the other procedures, rates for success and complications were comparable, and procedure times and x­ray doses tended to be lower in our analysis as compared to prior reports. CONCLUSION: Interventional electrophysiology, carried out by experienced operators and qualified staff, can be performed safely and effectively by attending physicians in a Belegarztsystem.

Present criteria for prophylactic ICD implantation: Insights from the EU-CERT-ICD (Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter Defibrillators in EUrope) project.

BACKGROUND: The clinical effectiveness of primary prevention implantable cardioverter defibrillator (ICD) therapy is under debate. It is urgently needed to better identify patients who benefit from prophylactic ICD therapy. The EUropean Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter Defibrillators (EU-CERT-ICD) completed in 2019 will assess this issue. SUMMARY: The EU-CERT-ICD is a prospective investigator-initiated non-randomized, controlled, multicenter observational cohort study done in 44 centers across 15 European countries. A total of 2327 patients with heart failure due to ischemic heart disease or dilated cardiomyopathy indicated for primary prophylactic ICD implantation were recruited between 2014 and 2018 (>1500 patients at first ICD implantation, >750 patients non-randomized non-ICD control group). The primary endpoint was all-cause mortality, and first appropriate shock was co-primary endpoint. At baseline, all patients underwent 12­lead ECG and Holter-ECG analysis using multiple advanced methods for risk stratification as well as documentation of clinical characteristics and laboratory values. The EU-CERT-ICD data will provide much needed information on the survival benefit of preventive ICD therapy and expand on previous prospective risk stratification studies which showed very good applicability of clinical parameters and advanced risk stratifiers in order to define patient subgroups with above or below average ICD benefit. CONCLUSION: The EU-CERT-ICD study will provide new and current data about effectiveness of primary prophylactic ICD implantation. The study also aims for improved risk stratification and patient selection using clinical risk markers in general, and advanced ECG risk markers in particular.

Morbidity and mortality in patients with cardiovascular risk factors and obstructive sleep apnoea: results from the DIAST-CHF cohort.

STUDY OBJECTIVES: Aim of the study was to investigate the association between obstructive sleep apnoea (OSA) and cardiovascular morbidity and mortality in a cohort of patients with cardiovascular risk factors. METHODS: In this prospective study, 378 patients of the DIAST-CHF cohort were screened for OSA by home polygraphy. Inclusion criteria were risk factors for diastolic heart failure, such as hypertension, diabetes mellitus, atherosclerotic disease, or history of chronic heart failure. Patients were followed up after 1, 2, 5, 9 and 10 years for the occurrence of major adverse cardiac and cerebrovascular events (MACE and MACCE). RESULTS: 344 patients were included in the analysis, of which 60% were diagnosed with OSA (apnoea-hypopnoea index ≥5/h). Overall mortality was higher in the OSA group (14.9% vs. 5.9%; p = 0.007), but significance disappeared after adjustment for age and sex (hazard ratio (HR) 1.89, 95% confidence interval (CI) 0.86-4.16, p = 0.12). There was no significant difference in the occurrence of MACE or MACCE in patients with OSA compared to those without OSA (MACE: 31% vs. 30%; p = 0.61; MACCE: 32% vs. 30%; p = 0.53). CONCLUSION: We did not find evidence of an adverse effect of OSA on cardiovascular morbidity and mortality in a cohort of patients with cardiovascular risk factors.

Rationale and design of the EU-CERT-ICD prospective study: comparative effectiveness of prophylactic ICD implantation.

AIMS: The clinical effectiveness of primary prevention implantable cardioverter defibrillator (ICD) therapy is under debate. The EUropean Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter Defibrillators (EU-CERT-ICD) aims to assess its current clinical value. METHODS AND RESULTS: The EU-CERT-ICD is a prospective investigator-initiated non-randomized, controlled, multicentre observational cohort study performed in 44 centres across 15 European Union countries. We will recruit 2250 patients with ischaemic or dilated cardiomyopathy and a guideline indication for primary prophylactic ICD implantation. This sample will include 1500 patients at their first ICD implantation and 750 patients who did not receive a primary prevention ICD despite having an indication for it (non-randomized control group). The primary endpoint is all-cause mortality; the co-primary endpoint in ICD patients is time to first appropriate shock. Secondary endpoints include sudden cardiac death, first inappropriate shock, any ICD shock, arrhythmogenic syncope, revision procedures, quality of life, and cost-effectiveness. At baseline (and prior to ICD implantation if applicable), all patients undergo 12-lead electrocardiogram (ECG) and Holter ECG analysis using multiple advanced methods for risk stratification as well as detailed documentation of clinical characteristics and laboratory values. Genetic biobanking is also organized. As of August 2018, baseline data of 2265 patients are complete. All subjects will be followed for up to 4.5 years. CONCLUSIONS: The EU-CERT-ICD study will provide a necessary update about clinical effectiveness of primary prophylactic ICD implantation. This study also aims for improved risk stratification and patient selection using clinical and ECG risk markers.

Reverse left ventricular structural remodeling after catheter ablation of atrial fibrillation in patients with preserved left ventricular function: Insights from cardiovascular magnetic resonance native T1 mapping.

BACKGROUND: Catheter ablation of atrial fibrillation (AF) improves left ventricular (LV) function in patients with LV systolic dysfunction, suggestive of underlying arrhythmia-induced adverse remodeling. OBJECTIVES: The objectives of this study were to evaluate whether arrhythmia-induced LV remodeling occurs in patients with AF and preserved LV systolic function and to assess whether this remodeling is reversible after restoration of sinus rhythm by catheter ablation. METHODS: Forty-three patients with AF and preserved LV systolic function (LV ejection fraction 62% ± 7%) underwent cardiovascular magnetic resonance (CMR) imaging before catheter ablation including native T1 mapping using a modified Look-Locker inversion recovery sequence. Twenty-five patients underwent follow-up CMR 3 months after catheter ablation. Twenty-two matched controls without AF underwent the same CMR protocol. RESULTS: Patients with AF had higher baseline LV native T1 values than did controls (1296 ± 55 ms vs 1243 ± 55 ms; P < .01). During a median follow-up of 9 months (interquartile range 4-14 months), 17 patients (40%) experienced AF recurrence. No differences in baseline T1 values were observed between patients with and without AF recurrence. There was a significant decrease in native T1 values in patients with successful restoration of sinus rhythm after catheter ablation at 3 months of follow-up CMR (1300 ± 45 ms vs 1270 ± 55 ms; P < .01), while they remain unchanged in patients with AF recurrence (1303 ± 51 ms vs 1309 ± 31 ms; P = .64). CONCLUSION: These preliminary results suggest that subclinical arrhythmia-induced LV structural remodeling occurs in patients with AF and preserved LV systolic function. This remodeling might be reversible after catheter ablation with successful restoration of sinus rhythm as quantified noninvasively and gadolinium-free by CMR native T1 mapping.

Data on differential multivariable risk prediction of appropriate shock vs. competing mortality.

This data article features supplementary figures and tables related to the article "Differential Multivariable risk prediction of appropriate shock vs. competing mortality - a prospective cohort study to estimate benefits from implantable cardioverter defibrillator therapy" (Bergau et al., 2018) [1]. The figures show the clinical study CONSORT graph (data that show the number of patients not-analyzable as well as a distribution of patients by outcomes) and the correlation scatter plot for risk scores of appropriate shock vs. mortality (data that show the calculated score values of the two scores plotted against each other). The tables show the results for the univariate Cox regressions for prediction of mortality and appropriate shock. For further information, please see Bergau et al. (2018) [1].

Differential multivariable risk prediction of appropriate shock versus competing mortality - A prospective cohort study to estimate benefits from ICD therapy.

BACKGROUND AND OBJECTIVE: We prospectively investigated combinations of risk stratifiers including multiple EP diagnostics in a cohort study of ICD patients. METHODS: For 672 enrolled patients, we collected history, LVEF, EP study and T-wave alternans testing, 24-h Holter, NT-proBNP, and the eGFR. All-cause mortality and first appropriate ICD shock were predefined endpoints. RESULTS: The 635 patients included in the final analyses were 63 ±â€¯13 years old, 81% were male, LVEF averaged 40 ±â€¯14%, 20% were inducible at EP study, 63% had a primary prophylactic ICD. During follow-up over 4.3 ±â€¯1.5 years, 108 patients died (4.0% per year), and appropriate shock therapy occurred in n = 96 (3.9% per year). In multivariate regression, age (p < 0.001), LVEF (p < 0.001), NYHA functional class (p = 0.007), eGFR (p = 0.024), a history of atrial fibrillation (p = 0.011), and NT-pro-BNP (p = 0.002) were predictors of mortality. LVEF (p = 0.002), inducibility at EP study (p = 0.007), and secondary prophylaxis (p = 0.002) were identified as independent predictors of appropriate shocks. A high annualized risk of shocks of about 10% per year was prevalent in the upper quintile of the shock score. In contrast, a low annual risk of shocks (1.8% per year) was found in the lower two quintiles of the shock score. The lower two quintiles of the mortality score featured an annual mortality <0.6%. CONCLUSIONS: In a prospective ICD patient cohort, a very good approximation of mortality versus arrhythmic risk was possible using a multivariable diagnostic strategy. EP stimulation is the best test to assess risk of arrhythmias resulting in ICD shocks.

A Randomized Controlled Trial to Evaluate the Safety and Efficacy of Cardiac Contractility Modulation.

OBJECTIVES: This study sought to confirm a subgroup analysis of the prior FIX-HF-5 (Evaluate Safety and Efficacy of the OPTIMIZER System in Subjects With Moderate-to-Severe Heart Failure) study showing that cardiac contractility modulation (CCM) improved exercise tolerance (ET) and quality of life in patients with ejection fractions between 25% and 45%. BACKGROUND: CCM therapy for New York Heart Association (NYHA) functional class III and IV heart failure (HF) patients consists of nonexcitatory electrical signals delivered to the heart during the absolute refractory period. METHODS: A total of 160 patients with NYHA functional class III or IV symptoms, QRS duration <130 ms, and ejection fraction ≥25% and ≤45% were randomized to continued medical therapy (control, n = 86) or CCM (treatment, n = 74, unblinded) for 24 weeks. Peak Vo2 (primary endpoint), Minnesota Living With Heart Failure questionnaire, NYHA functional class, and 6-min hall walk were measured at baseline and at 12 and 24 weeks. Bayesian repeated measures linear modeling was used for the primary endpoint analysis with 30% borrowing from the FIX-HF-5 subgroup. Safety was assessed by the percentage of patients free of device-related adverse events with a pre-specified lower bound of 70%. RESULTS: The difference in peak Vo2 between groups was 0.84 (95% Bayesian credible interval: 0.123 to 1.552) ml O2/kg/min, satisfying the primary endpoint. Minnesota Living With Heart Failure questionnaire (p < 0.001), NYHA functional class (p < 0.001), and 6-min hall walk (p = 0.02) were all better in the treatment versus control group. There were 7 device-related events, yielding a lower bound of 80% of patients free of events, satisfying the primary safety endpoint. The composite of cardiovascular death and HF hospitalizations was reduced from 10.8% to 2.9% (p = 0.048). CONCLUSIONS: CCM is safe, improves exercise tolerance and quality of life in the specified group of HF patients, and leads to fewer HF hospitalizations. (Evaluate Safety and Efficacy of the OPTIMIZER System in Subjects With Moderate-to-Severe Heart Failure; NCT01381172).

Predictors of mortality and ICD shock therapy in primary prophylactic ICD patients-A systematic review and meta-analysis.

BACKGROUND: There is evidence that the benefit of a primary prophylactic ICD therapy is not equal in all patients. PURPOSE: To evaluate risk factors of appropriate shocks and all- cause mortality in patients with a primary prophylactic ICD regarding contemporary studies. DATA SOURCE: PubMed, LIVIVO, Cochrane CENTRAL between 2010 and 2016. STUDY SELECTION: Studies were eligible if at least one of the endpoints of interest were reported. DATA EXTRACTION: All abstracts were independently reviewed by at least two authors. The full text of all selected studies was then analysed in detail. DATA SYNTHESIS: Our search strategy retrieved 608 abstracts. After exclusion of unsuitable studies, 36 papers with a total patient number of 47282 were included in our analysis. All-cause mortality was significantly associated with increasing age (HR 1.41, CI 1.29-1.53), left ventricular function (LVEF; HR 1.21, CI 1.14-1.29), ischemic cardiomyopathy (ICM; HR 1.37, CI 1.14-1.66) and co-morbidities such as impaired renal function (HR 2.30, CI 1.97-2.69). Although, younger age (HR 0.96, CI 0.85-1.09), impaired LVEF (HR 1.26, CI 0.89-1.78) and ischemic cardiomyopathy (HR 2.22, CI 0.83-5.93) were associated with a higher risk of appropriate shocks, none of these factors reached statistical significance. LIMITATIONS: Individual patient data were not available for most studies. CONCLUSION: In this meta-analysis of contemporary clinical studies, all-cause mortality is predicted by a variety of clinical characteristics including LVEF. On the other hand, the risk of appropriate shocks might be associated with impaired LVEF and ischemic cardiomyopathy. Further prospective studies are required to verify risk factors for appropriate shocks other than LVEF to help select appropriate patients for primary prophylactic ICD-therapy.

[Malignant bileaflet mitral valve prolapse syndrome in otherwise idiopathic ventricular fibrillation]. / Malignes Mitralklappenprolapssyndrom bei "idiopathischem" Kammerflimmern.

A 32-year-old, otherwise healthy woman was admitted after successful out-of-hospital resuscitation due to ventricular fibrillation. Established cardiac, pulmonary, metabolic, and toxicological causes were excluded. However, persisting (biphasic) negative T waves in the inferior ECG leads and premature ventricular contractions (PVC) were noted. PVC morphology indicated a focus alternating between the posterior papillary muscle/the left posterior fascicle and the left ventricular outflow tract region/anterior papillary muscle. Echocardiography revealed a bileaflet mitral prolapse with mild mitral valve regurgitation. This case is a typical presentation of the recently described malignant bileaflet mitral valve prolapse syndrome. The patient was discharged without overt neurological deficit after implantation of a cardioverter-defibrillator.

Prediction of Appropriate Shocks Using 24-Hour Holter Variables and T-Wave Alternans After First Implantable Cardioverter-Defibrillator Implantation in Patients With Ischemic or Nonischemic Cardiomyopathy.

In patients treated with implantable cardioverter defibrillator (ICD), prediction of both overall survival and occurrence of shocks is important if improved patient selection is desired. We prospectively studied the predictive value of biomarkers and indexes of cardiac and renal function and spectral microvolt T-wave alternans testing and 24-hour Holter variables in a population who underwent first ICD implantation. Consecutive patients in sinus rhythm with ischemic or dilated cardiomyopathy scheduled for primary or secondary prophylactic ICD implantation were enrolled. Exercise microvolt T-wave alternans and 24-hour Holter for number of ventricular premature contractions (VPCs), deceleration capacity, heart rate variability, and heart rate turbulence were done. Death of any cause and first appropriate ICD shock were defined as end points. Over 33 ± 15 months of follow-up, 36 of 253 patients (14%) received appropriate shocks and 39 of 253 patients (15%) died. Only 3 of 253 patients (1%) died after receiving at least 1 appropriate shock. In univariate analyses, New York Heart Association class, ejection fraction, N-terminal pro brain-type natriuretic peptide (NT-proBNP), renal function, ICD indication, deceleration capacity, heart rate variability, and heart rate turbulence were predictive of all-cause mortality and VPC number and deceleration capacity predicted first appropriate shock. NT-proBNP (≥1,600 pg/ml) was identified as the only independent predictor of all-cause mortality (hazard ratio 3.0, confidence interval 1.3 to 7.3, p = 0.014). In contrast, VPC number predicted appropriate shocks (hazard ratio 2.3, confidence interval 1.0 to 5.5, p = 0.047) as the only independent risk marker. In conclusion, NT-proBNP is a strong independent predictor of mortality in a typical prospective cohort of newly implanted patients with ICD, among many electrocardiographic and clinical variables studied. Number of VPCs was identified as a predictor of appropriate shocks (clinicaltrials.gov: NCT02010515).

Sex difference in appropriate shocks but not mortality during long-term follow-up in patients with implantable cardioverter-defibrillators.

AIMS: Implantable cardioverter-defibrillators (ICDs) have been shown to improve survival, although a considerable number of patients never receive therapy. Implantable cardioverter-defibrillators are routinely implanted regardless of sex. There is continuing controversy whether major outcomes differ between men and women. METHODS AND RESULTS: In this retrospective single-centre study, 1151 consecutive patients (19% women) undergoing ICD implantation between 1998 and 2010 were followed for mortality and first appropriate ICD shock over 4.9 ± 2.7 years. Sex-related differences were investigated using multivariable Cox models adjusting for potential confounders. During follow-up, 318 patients died, a rate of 5.9% per year among men and 4.6% among women (uncorrected P = 0.08); 266 patients received a first appropriate ICD shock (6.3% per year among men vs. 3.6% among women, P = 0.002). After multivariate correction, independent predictors of all-cause mortality were age (hazard ratio, HR = 1.04 per year of age, 95% confidence interval (CI) [1.03-1.06], P < 0.001), left ventricular ejection fraction (HR = 0.98 per %, 95% CI [0.97-1.00], P = 0.025), renal function (HR = 0.99 per mL/min/1.73 m(2), 95% CI [0.99-1.00], P = 0.009), use of diuretics (HR = 1.81, 95% CI [1.29-2.54], P = 0.0023), peripheral arterial disease (HR = 2.21, 95% CI [1.62-3.00], P < 0.001), and chronic obstructive pulmonary disease (HR = 1.48, 95% CI [1.13-1.94], P = 0.029), but not sex. Female sex (HR = 0.51, 95% CI [0.33-0.81], P = 0.013), older age (HR = 0.98, 95% CI [0.97-0.99], P < 0.001), and primary prophylactic ICD indication (HR = 0.69, 95% CI [0.52-0.93], P = 0.043) were independent predictors for less appropriate shocks. CONCLUSION: Women receive 50% less appropriate shocks than men having similar mortality in this large single-centre population. These data may pertain to individually improved selection of defibrillator candidates using risk factors, e.g. sex as demonstrated in this study.

Longevity of implantable cardioverter-defibrillators in a single-center population.

BACKGROUND OR PURPOSE: Real-life comparative data of implantable cardioverter-defibrillator (ICD) longevity are needed to identify the best possible device longevity for optimal patient comfort and to minimize risk for multiple replacements. METHODS: We retrospectively studied ICD longevity in a large single-center population. At our institution, 1272 consecutive patients were implanted with 1665 ICD or cardiac resynchronization therapy with defibrillator (CRT-D) devices between 1998 and 2010. Device data and follow-up were retrieved from the continuous ICD clinic documentation, and generator replacements were verified from the hospital charts. Kaplan-Meier event probabilities for the time to generator replacement were calculated according to device type, pacing percentage (sum of atrial, right and left ventricular pacing, if applicable) and right ventricular pacing threshold, incidence of ICD shocks, and manufacturer. Multivariate Cox proportional hazards regression was performed in addition. RESULTS: A total of 470 devices were replaced for elective replacement indicator. These occurred after 5.4 years (95% confidence interval, 5.1 to 5.6 years) in 175 of 625 implanted Boston Scientific or Guidant devices, after 5.7 years (5.5 to 5.9 years) in 266 of 883 Medtronic devices, and 5.2 years (5.0 to 5.4 years) in 29 of 157 Biotronik devices, respectively. Differences between manufacturers remained significant upon multivariate analysis (Medtronic vs. Boston Scientific: P = 0.01; both vs. Biotronik: P < 0.01) as did differences of device type (single- and dual-chamber ICD vs. CRT-D, P < 0.01) and pacing percentage (P < 0.01). Pacing output and ICD shocks did not influence battery longevity. CONCLUSION: ICD longevity differed significantly between manufacturers, independent of device type or pacing parameters.

A randomized study of remote monitoring and fluid monitoring for the management of patients with implanted cardiac arrhythmia devices.

AIMS: Only limited comparative data exist on the benefits of fluid monitoring (FM) combined with remote monitoring (RM) regarding morbidity and mortality of heart failure (HF) patients. This prospective single-centre randomized pilot study aimed to estimate the influence of RM in combination with FM on HF hospitalizations as well as ventricular tachyarrhythmias and mortality. METHODS AND RESULTS: Patients with standard indication for implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy and defibrillator were implanted with devices capable of RM and FM, and were followed for 15 months. Subjects were randomly allocated to RM including OptiVol and predefined management of alerts (remote group), or standard in-office visits every 3 months (control group). A total of 176 patients (77% male; 66 ± 12 years; left ventricular ejection fraction (LVEF) 32 ± 11%; ischemic cardiomyopathy 50%; CRT device 50%; primary prevention 85%) were analysed. Cox proportional hazard analysis on the time to first HF-related hospitalization showed a hazard ratio of 1.23 [0.62-2.44] (P = 0.551) favouring the control group. In the remote group, 13 patients (15%) experienced ICD shocks vs. 10 patients (11%) in the control group (P = 0.512). The average time to first ICD shock was 212 ± 173 days in the remote arm and 212 ± 143 days in the control arm (P = 0.994). The Kaplan-Meier estimate of mortality after 1 year was 8.6% (eight deaths) in the remote group vs. 4.6% in the control group (six deaths; P = 0.502). CONCLUSION: In a single-centre randomized pilot study of RM in combination with FM, no significant influence on HF-related hospitalizations, ICD shocks, or mortality was found.

Rationale and design of the MONITOR-ICD study: a randomized comparison of economic and clinical effects of automatic remote MONITORing versus control in patients with Implantable Cardioverter Defibrillators.

BACKGROUND AND AIMS: Implantable cardioverter defibrillator (ICD) remote follow-up and ICD remote monitoring (RM) are established means of ICD follow-up. The reduction of the number of in-office visits and the time to decision is proven, but the true clinical benefit is still unknown. Cost and cost-effectiveness of RM remain leading issues for its dissemination. The MONITOR-ICD study has been designed to assess costs, cost-effectiveness, and clinical benefits of RM versus standard-care follow-up in a prospective multicenter randomized controlled trial. METHODS AND RESULTS: Patients indicated for single- or dual-chamber ICD are eligible for the study and are implanted an RM-capable Biotronik ICD (Lumax VR-T or Lumax DR-T; Biotronik SE & Co KG, Berlin, Germany). Implantable cardioverter defibrillator programming and alert-based clinical responses in the RM group are highly standardized by protocol. As of December 2011, recruitment has been completed, and 416 patients have been enrolled. Subjects are followed-up for a minimum of 12months and a maximum of 24months, ending in January 2013. Disease-specific costs from a societal perspective have been defined as primary end point and will be compared between RM and standard-care groups. Secondary end points include ICD shocks (including appropriate and inappropriate shocks), cardiovascular hospitalizations and cardiovascular mortality, and additional health economic end points. CONCLUSIONS: The MONITOR-ICD study will be an important randomized RM study to report data on a primary economic end point in 2014. Its results on ICD shocks will add to the currently available evidence on clinical benefit of RM.

Measurement of Left Atrial Pressure is a Good Predictor of Freedom From Atrial Fibrillation.

BACKGROUND: It is suggested that an elevated left atrial pressure (LAP) promotes ectopic beats emanating in the pulmonary veins (PVs) and that LAP might be a marker for structural remodeling. This study aimed to identify if the quantification of LAP correlates with structural changes of the LA and may therefore be associated with outcomes following pulmonary vein isolation (PVI). METHODS: We analysed data from 120 patients, referred to PVI due to drug-refractory atrial fibrillation (AF) (age 63±8; 57% men). The maximum (mLAP) and mean LAP (meLAP) were measured after transseptal puncture. RESULTS AND CONCLUSIONS: Within a mean follow-up of 303±95 days, 60% of the patients maintained in sinus rhythm after the initial procedure and 78% after repeated PVI. Performing univariate Cox-regression analysis, type of AF, LA-volume (LAV), mLAP and the meLAP were significant predictors of recurrence after PVI (p=0.03; p=0.001; p=0.01). In multivariate analysis mLAP>18mmHg, LAV>100 ml and the presence of persistent AF were significant predictors (p=0.001; p=0.019; p=0.017). The mLAP >18 mmHg was associated with a hazard ratio of 3.8. Analyzing receiver-operator characteristics, the area under the curve for mLAP was 0.75 (p<0.01). mLAP >18 mmHg predicts recurrence with a sensitivity of 77 % and specificity of 60 %. There was a linear correlation between the LAV from MDCT and mLAP (p = 0.01, R2 = 0.61). The mLAP measured invasively displays a significant predictor for AF recurrence after PVI. There is a good correlation between LAP and LAV and both factors may be useful to quantify LA remodeling.

Remote magnetic navigation for circumferential pulmonary vein ablation: single-catheter technique or additional use of a circular mapping catheter?

PURPOSE: Remote magnetic navigation (RMN) is utilized for catheter guidance during pulmonary vein ablation (PVA). We aimed to determine whether the additional use of a circular mapping catheter (CMC) influences efficacy and outcome of RMN-guided PVA. METHODS: A total of 80 consecutive subjects (65 % male, age 62 ± 9 years) underwent circumferential PVA with a 3D mapping system and an RMN-guided irrigated catheter. Procedural endpoint was complete PV isolation (PVI), total radiofrequency (RF) time >60 min, or procedure duration >5 h. PVI was defined as an entrance and/or exit block, diagnosed with a CMC within the PV ostium or by pacing via the roving RMN-guided catheter (single-catheter technique). Prolonged Holter monitoring after 3 and 6 months was used to detect atrial tachyarrhythmia (AT/AF) recurrences. RESULTS: Complete PVI was achieved in 56 % (45/80) of all subjects (isolated PVs per patient, 3.1 ± 1.2; RF time, 56.3 ± 17.2 min; procedure duration, 3.8 ± 0.8 h). Prospective validation of the single-catheter technique for diagnosing PVI demonstrated high concordance (94 %) with blinded CMC results. CMC use in first-time PVA was associated with similar total RF and procedure times but higher PV isolation rate. Upon multivariate analysis, CMC use, female gender, left PV, smaller PV ostium and repeat PVA predicted PVI during RMN-guided ablation. Persistent AF and mitral regurgitation at baseline and the number of non-isolated PVs predicted AT/AF recurrence during follow-up. CONCLUSIONS: Concomitant CMC use for first-time, RMN-guided PVA is associated with similar procedure duration but higher PV isolation rates as compared to a single-catheter approach. Since the number of isolated PVs predicts freedom from AT/AF, CMC utilization appears advisable for first-time, RMN-guided PVA.

Single-ring ablation compared with standard circumferential pulmonary vein isolation using remote magnetic catheter navigation.

PURPOSE: In ablation of atrial fibrillation, the single-ring method aims for isolation of the posterior wall of the left atrium (LA) including the pulmonary veins (PVs) but avoiding posterior LA lesions. The aim of this randomized prospective study was to evaluate safety and efficacy of remote magnetic navigation (RMN)-guided single-ring ablation strategy as compared to standard RMN-guided circumferential PV ablation (PVA). METHODS: Eighty consecutive patients undergoing PVA were enrolled prospectively and randomized equally into two study groups. RMN using the Stereotaxis system and open-irrigated 3.5-mm ablation catheters were used with a 3D mapping system in all procedures. Forty patients underwent RMN-guided single-ring ablation, and 40 patients received RMN-guided circumferential PVA. RESULTS: In the circumferential group, 3.3 ± 1.1 PVs were successfully isolated at the end of the procedure as compared to 3.1 ± 1.3 in the single-ring (box) group (p=0.38). All patients in the box group required additional posterior lesions in order to achieve electrical isolation of the PVs. Single-ring ablation was associated with longer procedure duration (p=0.01) and ablation time (p=0.001). After a single procedure, the proportion of patients free of any atrial tachycardia (AT)/atrial fibrillation (AF) episode at 12-month follow-up was 57 % in the box group and 58 % in the circ group. Using RMN, only minor complications have been observed. CONCLUSIONS: RMN-guided single-ring PVA provides comparable acute and long-term success rates as compared to RMN-guided circumferential PVA but requires additional posterior lesions to achieve PV isolation and increased procedure and ablation time. Procedural complication rates are low when using RMN.