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Relatively few data have been reported on prospective changes in global longitudinal strain ( GLS) following cardiac resynchronization therapy ( CRT), and none are available on GLS during physical exercise. We investigated the effects of CRT on GLS, assessed by speckle tracking two-dimensional (2 D) echocardiography, at rest and during exercise after a mid-term follow-up. Twenty consecutive CRT patients (45% ischaemic) were assessed prospectively by speckle tracking 2 D echocardiography before implant (at rest) and at mid-term follow-up (during rest and bicycle exercise). GLS, septum and lateral wall longitudinal strain, left ventricular ejection fraction ( LVEF), and conventional functional variables were evaluated at baseline and follow-up. All patients completed the study protocol at rest. Exercise images were available in 90% of the patients. At follow-up, GLS improved at rest from −7·1 ± 2·6% to −9·1 ± 4·5% ( P<0·01), with a further increase to −11 ± 5·1% during exercise ( P<0·001). Longitudinal strain increased at rest both in the septum and in the lateral wall, with an additional increase during exercise in the lateral wall ( P<0·05). GLS correlated with LVEF both at rest ( r = −0·55 and r = −0·91 at baseline and 3 months, respectively; P<0·05) and during exercise ( r = −0·89, P<0·05). Improvement in GLS during rest and exercise can be observed in CRT patients at mid-term follow-up and seems to correlate with changes in LVEF. GLS may be a valuable method to assess left ventricular function during rest and exercise. [ABSTRACT FROM AUTHOR]

Abstract: Background: Haemodynamic and functional effects of cardiac resynchronization therapy (CRT) have been studied mostly at rest. CRT effects on left ventricular (LV) dyssynchrony and function during stress have not been evaluated in detail. Aims: We studied the electromechanical effects of CRT at rest and during Dobutamine stress echocardiography (DSE), during active and withheld CRT. Methods: Twenty-one responders to CRT (62±12 yr) were assessed by walking test, quality of life, and BNP with active CRT (“on”) and 2 weeks after pacing withdrawal (“off”). DSE (10 μg/kg/min) was performed both at “on” and “off” to evaluate dyssynchrony parameters, systolic and diastolic function. Results: At rest, CRT withdrawal was associated with an increased interventricular mechanical delay (IVMD, from 21±18 ms to 49±24 ms, p <0.001) and impaired intraventricular synchrony. There was a significant decrease in LV systolic function and LV filling time. Dobutamine infusion had no impact on inter- and intraventricular synchrony. During stress, there was an improvement in LV performance both at “on” and “off”. However, LV dp/dt, aortic VTI, cardiac output, mean systolic peak velocities and LV filling time during dobutamine stress were significantly greater with CRT “on”. Conclusion: In long-term responders, CRT improves LV performance both at rest and during dobutamine stress. This is attributable to an improvement in LV synchrony, which is maintained during stress. [Copyright &y& Elsevier]

Heart failure (HF) is considered as an epidemic and affects 2% of the population in the Western world. About 15 30% of patients with HF and reduced ejection fraction (HFrEF) also have prolonged QRS duration on the surface ECG, most commonly as a result of left bundle branch block (LBBB). Increased QRS duration is a marker of a dyssynchronous activation, and subsequent contraction, pattern in the left ventricle (LV). When dyssynchrony is superimposed on the failing heart it further reduced systolic function and ultimately worsens outcome. During the past 15 years several randomized controlled clinical trials have documented that resynchronization of the dyssynchronous failing heart with a biventricular pacemaker cardiac resynchronization therapy (CRT) which can restore a more synchronous activation and contraction pattern. This translates in halted or reversed disease progression and improved clinical outcome, including reduced mortality. In this review, we will discuss several aspects of CRT including mechanisms of dyssynchrony and resynchronization in the failing heart, evidence of CRT efficacy derived from clinical trials and current challenges in CRT including patient selection and optimization of therapy delivery. Last, we will discuss future perspectives including the role of CRT to prevent adverse events in patients with an indication for antibradycardia pacing, the role of leadless pacing in the CRT setting as well as a new clinical arena where dyssynchrony and resynchronization may be important. [ABSTRACT FROM AUTHOR]

Background: Health-related quality of life (HRQL) in hypertrophic cardiomyopathy (HCM) patients with implantable cardioverter-defibrillators (ICDs) is largely unknown. The aim was to assess HRQL, including comparisons between groups, using the questionnaire SF-36, and compare it to a Swedish age- and sex-matched population.Methods and Results: Validated data on adult HCM patients with ICDs were used. The SF-36 response rate was 82.5 % and 245 patients (mean age 55.9 years, 70.2 % men) were analyzed using the Mann-Whitney U-test, t-test, Spearman correlation and effect size calculations. In all SF-36 domains the patients' score was lower (p-value of <0.0001) than norms except for bodily pain. The general health domain showed the highest effect size (0.77) and the impact was more pronounced in the SF-36 physical component summary score (0.62) than the mental component summary score (0.46). Older age was correlated with lower scores on the physical component and higher scores on the mental component. Atrial fibrillation and/or systolic heart failure were associated with worse physical health. HRQL was similar in primary vs secondary prevention cases. Inappropriate ICD shock was associated with worse mental health while appropriate therapy trended toward better mental health.Conclusion: HCM patients with ICDs suffer from poor HRQL regardless of age, sex, or primary vs secondary prevention indication. Atrial fibrillation and systolic heart failure are determinants of poor physical health. Inappropriate shocks, but not appropriate therapies, are associated with poorer mental health. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the long-term clinical outcome and device performance of cardiac resynchronization therapy in a consecutive sample of patients with moderate to severe heart failure. Methods and Results: Between 1998 and 2000, forty consecutive patients with drug-refractory heart failure due to ischemic or idiopathic dilated cardiomyopathy were selected for cardiac resynchronization therapy (CRT). After successful implantation of the coronary sinus lead (n = 35, 88%), patients were followed every sixth month by New York Heart Association (NYHA) functional class, the 6-minute walking test (6´ walk), quality of life (QoL, Minnesota), and pacemaker control. NYHA-class and 6´ walk were significantly improved after 6 months and continued to improve gradually until 36 months of follow-up. The QoL improvement at 6 months was sustained over 3 years. After 3 years, the β-blocker dose could be increased in 10/23 patients as compared to baseline. Nine patients had to be re-operated. Coronary sinus lead thresholds were stable over time. Conclusion: The clinical improvements by CRT are sustained over 3 years of follow-up. In the setting of a University Medical Center, CRT can be applied in clinical routine with excellent clinical outcome, acceptable implantation success, and stable device performance over time. [ABSTRACT FROM AUTHOR]

STEINHAUS, D., et. al.: Implant Experience with an Implantable Hemodynamic Monitor for the Management of Symptomatic Heart Failure. Introduction: Management of congestive heart failure is a serious public health problem. The use of implantable hemodynamic monitors (IHMs) may assist in this management by providing continuous ambulatory filling pressure status for optimal volume management. Methods and Results: The Chronicle® system includes an implanted monitor, a pressure sensor lead with passive fixation, an external pressure reference (EPR), and data retrieval and viewing components. The tip of the lead is placed near the right ventricular outflow tract to minimize risk of sensor tissue encapsulation. Implant technique and lead placement is similar to that of a permanent pacemaker. After the system had been successfully implanted in 148 patients, the type and frequency of implant-related adverse events were similar to a single-chamber pacemaker implant. R-wave amplitude was 15.2 ± 6.7 mV and the pressure waveform signal was acceptable in all but two patients in whom presence of artifacts required lead repositioning. Implant procedure time was not influenced by experience, remaining constant throughout the study. Conclusion: Based on this evaluation, permanent placement of an IHM in symptomatic heart failure patients is technically feasible. Further investigation is warranted to evaluate the use of the continuous hemodynamic data in management of heart failure patients. (PACE 2005; 28:747–753) [ABSTRACT FROM AUTHOR]

The health care costs for heart failure are substantial. Studies indicate that hospital treatment constitutes 65–75% of these. The aim of this study was to assess total and heart failure related hospital days as well as safety and efficacy of biventricular pacing in 16 patients with severe heart failure and delayed intraventricular conduction (QRS duration <150 ms). They were implanted with a biventricular pacemaker and followed by NYHA class, 6-min walk test and quality of life for a mean of 291±76 days. Total number of hospital days and the need for hospitalisations were monitored. Thirteen responders improved by at least one functional class. After 6 months of pacing the 6-min walk test improved from 375±83 m to 437±73 m (P<0.001) and Minnesota Living with Heart Failure quality of life score from 41±19 to 24±17 (P<0.001) compared to baseline. The need for hospital care decreased significantly after biventricular pacing. The total number of hospital days in all patients was 253 the year before compared to 45 the year after biventricular pacing (P<0.01). For heart failure related hospital days the corresponding figures were 183 and 39 days, respectively (P<0.01). Biventricular pacing improved 13/16 patients with severe heart failure and wide QRS complexes in this open study. The improvement resulted in a reduced need for hospital care. [ABSTRACT FROM PUBLISHER]

Introduction: Dual‐coil leads (DC‐leads) were the standard of choice since the first nonthoracotomy implantable cardioverter/defibrillator (ICD). We used contemporary data to determine if DC‐leads offer any advantage over single‐coil leads (SC‐leads), in terms of defibrillation efficacy, safety, clinical outcome, and complication rates. Methods and Results: In the Shockless IMPLant Evaluation study, 2500 patients received a first implanted ICD and were randomized to implantation with or without defibrillation testing. Two thousand and four hundred seventy‐five patients received SC‐coil or DC‐coil leads (SC‐leads in 1025/2475 patients; 41.4%). In patients who underwent defibrillation testing (n = 1204), patients with both lead types were equally likely to achieve an adequate defibrillation safety margin (88.8% vs 91.2%; P = 0.16). There was no overall effect of lead type on the primary study endpoint of "failed appropriate shock or arrhythmic death" (adjusted HR 1.18; 95% CI, 0.86‐1.62; P = 0.300), and on all‐cause mortality (SC‐leads: 5.34%/year; DC‐leads: 5.48%/year; adjusted HR 1.16; 95% CI, 0.94‐1.43; P = 0.168). However, among patients without prior heart failure (HF), and SC‐leads had a significantly higher risk of failed appropriate shock or arrhythmic death (adjusted HR 7.02; 95% CI, 2.41‐20.5). There were no differences in complication rates. Conclusion: In this nonrandomized evaluation, there was no overall difference in defibrillation efficacy, safety, outcome, and complication rates between SC‐leads and DC‐leads. However, DC‐leads were associated with a reduction in the composite of failed appropriate shock or arrhythmic death in the subgroup of non‐HF patients. Considering riskier future lead extraction with DC‐leads, SC‐leads appears to be preferable in the majority of patients. [ABSTRACT FROM AUTHOR]

Objectives. To explore sex differences regarding indication for atrio-ventricular junction ablation (AVJ), choice of pacing system, complications to pacemaker treatment, long-term outcome, and cause of death after AVJ ablation. Design. 700 patients who had undergone AVJ ablation between January 1990 and December 2010 were included. Data were retrieved from the patients´ medical records and the Swedish Pacemaker and Implantable Cardioverter-Defibrillator Registry. Information about admission to hospital and cause of death was retrieved from the National Board of Health and Welfare. Results. Mean follow-up was 90 ± 64 months. Indication for AVJ ablation, choice of pacing system, and outcome after AVJ ablation differed between the sexes. The men had more often permanent atrial fibrillation, p = .0001, and a VVIR pacemaker or cardiac resynchronization therapy (CRT) implanted prior to ablation, p = .0001. Heart failure was present in 44% of the men vs. 28% of the women, p = .0001. LVEF decreased slightly in the whole cohort after the AVJ ablation. There were no sex differences in complication rates due to the pacemaker/ICD treatment, p = .3 or mortality due to AVJ ablation. Conclusion. In this long-term follow-up in patients with atrial fibrillation treated with AVJ ablation and pacing, indication, choice of pacing system, and morbidity differed but there were no sex differences regarding survival or primary cause of death found. The main factor influencing survival was age at the time of ablation. Women less often received treatment with ICD and/or CRT when indication was present compared with men. [ABSTRACT FROM AUTHOR]

Aims The European CRT Survey is a joint initiative of the Heart Failure Association (HFA) and the European Heart Rhythm Association (EHRA) of the European Society of Cardiology evaluating the contemporary implantation practice of cardiac resynchronization therapy (CRT) in Europe. Methods and results Patients who had a successful CRT implantation were enrolled from 141 centres in 13 countries between November 2008 and June 2009. Baseline demographics, clinical and implantation data were collected, with a follow-up of ∼1 year (9–15 months). The current report describes clinical outcomes including symptom severity, cardiovascular (CV) hospitalization, and survival. A total of 2438 patients were enrolled, and follow-up data were acquired from 2111 patients (87%). The population included important groups of patients poorly represented in randomized controlled trials, including very elderly patients and those with prior device implantation, atrial fibrillation, and/or QRS duration <120 ms. Investigators reported substantial improvement in New York Heart Association (NYHA) functional class at follow-up. Patient self-assessment indicated that 81% of the patients felt improved, 16% reported no change, and 4% reported deterioration. During follow-up, 207 (10%) patients died, 346 (16%) had a CV hospitalization, and 501 (24%) died or had CV hospitalization. Worse NYHA functional class, atrial fibrillation, ischaemic aetiology, and device type (CRT-P, i.e. CRT alone) were associated with poorer survival. Women had a better outcome, as did patients who had a CRT-D (with an implantable cardioverter defibrillator function) device. Conclusions Outcomes including death and hospitalization in this European CRT survey were consistent with results from clinical trials of CRT. At 1 year follow-up, most patients who received a CRT device considered their symptoms improved compared with their pre-implant assessment. Although prospective, this is an observational study of successful CRT implantations, and outcomes in subgroup analyses must be interpreted with appropriate conservatism. [ABSTRACT FROM AUTHOR]

Aims Cardiac resynchronization therapy (CRT) is an effective treatment for a subset of patients with chronic heart failure. Data on the benefit of CRT in heart failure patients with previous right ventricular pacemakers or standard defibrillators are sparse. Methods and results The European (HFA, Heart Failure Association/EHRA, European Heart Rhythm Association) CRT Survey enrolled patients from 141 centres in 13 countries in Europe collecting baseline demographic, echocardiographic, clinical, and implant data, with follow-up at ∼1 year. The present analysis reports implantation data and 1 year outcomes regarding New York Heart Association (NYHA) class, global patient assessment, hospitalizations, complications, and mortality in patients undergoing de novo CRT implantations compared with those receiving an upgrade of a previously implanted device (pacemaker or implantable cardioverter–defibrillators). This analysis includes 2367 CRT implant procedures of which 692 (28%) were upgrades to CRT. Distribution of NYHA functional class and left ventricular function were similar between the groups. Procedural duration was also similar, although fluoroscopy time was shorter in the ‘upgrades’. There was no difference in the frequency of peri-procedural complications. There were similar improvements in NYHA functional class and similar reduction in QRS duration, but more patients reported unchanged global assessment status in the upgraded group. Total and cause-specific mortality at 1 year was low and the same in both groups. Conclusions More than one quarter of all CRT procedures are upgrades from existing systems, although this group has not been subject to randomized clinical trials. Our data suggest that there are no significant differences in clinical outcomes or complication rates between upgrades and de novo procedures. Clinical study no NCT 01185392 [ABSTRACT FROM AUTHOR]