A total of 30% to 40% of patients with congestive heart failure eligible for cardiac resynchronization therapy (CRT) either do not respond to conventional CRT or remain untreated due to an inability ...or impediment to coronary sinus (CS) lead implantation. The WiSE-CRT system (EBR Systems, Sunnyvale, California) was developed to address this at-risk patient population by performing biventricular pacing via a wireless left ventricular (LV) endocardial pacing electrode.
The SELECT-LV (Safety and Performance of Electrodes implanted in the Left Ventricle) study is a prospective multicenter non-randomized trial assessing the safety and performance of the WiSE-CRT system.
A total of 35 patients indicated for CRT who had "failed" conventional CRT underwent implantation of an LV endocardial pacing electrode and a subcutaneous pulse generator. System performance, clinical efficacy, and safety events were assessed out to 6 months post-implant.
The procedure was successful in 97.1% (n = 34) of attempted implants. The most common indications for endocardial LV pacing were difficult CS anatomy (n =12), failure to respond to conventional CRT (n = 10), and a high CS pacing threshold or phrenic nerve capture (n = 5). The primary performance endpoint, biventricular pacing on the 12-lead electrocardiogram at 1 month, was achieved in 33 of 34 patients. A total of 28 patients (84.8%) had improvement in the clinical composite score at 6 months, and 21 (66%) demonstrated a positive echocardiographic CRT response (≥5% absolute increase in LV ejection fraction). There were no pericardial effusions, but serious procedure/device-related events occurred in 3 patients (8.6%) within 24 h, and 8 patients (22.9%) between 24 h and 1 month.
The SELECT-LV study demonstrates the clinical feasibility for the WiSE-CRT system, and provided clinical benefits to a majority of patients within an otherwise "failed" CRT population. (Safety and Performance of Electrodes Implanted in the Left Ventricle SELECT-LV; NCT01905670).
SyncAV, a device-based cardiac resynchronization therapy (CRT) algorithm, promotes electrical optimization by dynamically adjusting atrioventricular intervals.
The purpose of this study was to ...evaluate the impact of SyncAV on heart failure hospitalizations (HFHs) and related costs in a real-world CRT cohort.
Patients with SyncAV-capable CRT devices followed by remote monitoring and enrolled in Medicare fee-for-service for at least 1 year preimplant and up to 2 years postimplant were studied. Patients with SyncAV OFF were 4:1 matched to those with SyncAV ON on preimplant HFH rate, demographics, comorbidities, disease etiology, and left bundle branch block. HFHs were determined from the primary diagnosis of inpatient hospitalizations, and the cost for each event was the sum of Medicare, supplemental insurance, and patient payment.
After 4:1 propensity score matching, 3630 patients were studied (mean age 75 ± 8 years; 1386 38% female), including 726 (25%) patients with SyncAV ON. The pre-CRT HFH rate was 0.338 HFH events per patient-year. Overall, CRT diminished the HFH rate to 0.204 events per patient-year (P < .001). SyncAV elicited a larger reduction in HFH rate (SyncAV ON: hazard ratio HR 0.52; 95% confidence interval CI 0.41–0.66; P < .001 and SyncAV OFF: HR 0.68; 95% CI 0.59–0.77; P < .001). After 2 years, the HFH rate was lower in the SyncAV ON group than in the SyncAV OFF group (0.143 HFHs per patient-year vs 0.193 HFHs per patient-year; HR 0.70; 95% CI 0.55–0.89; P = .003) and fewer HFHs were followed by 30-day HFH readmissions (4.41% vs 7.68%; P = .003) and 30-day all-cause hospital readmissions (7.04% vs 10.01%; P = .010). The total 2-year HFH-associated costs per patient were lower with SyncAV ON (difference $1135; 90% CI $93–$2109; P = .038).
This large, real-world, propensity score–matched study demonstrates that SyncAV CRT is associated with significantly reduced HFHs and associated costs, incremental to standard CRT.
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The His-SYNC pilot trial was the first randomized comparison between His bundle pacing in lieu of a left ventricular lead for cardiac resynchronization therapy (His-CRT) and biventricular pacing ...(BiV-CRT), but was limited by high rates of crossover.
To evaluate the results of the His-SYNC pilot trial utilizing treatment-received (TR) and per-protocol (PP) analyses.
The His-SYNC pilot was a multicenter, prospective, single-blinded, randomized, controlled trial comparing His-CRT vs BiV-CRT in patients meeting standard indications for CRT (eg, NYHA II-IV patients with QRS >120 ms). Crossovers were required based on prespecified criteria. The primary endpoints analyzed included improvement in QRS duration, left ventricular ejection fraction (LVEF), and freedom from cardiovascular (CV) hospitalization and mortality.
Among 41 patients enrolled (aged 64 ± 13 years, 38% female, LVEF 28%, QRS 168 ± 18 ms), 21 were randomized to His-CRT and 20 to BiV-CRT. Crossover occurred in 48% of His-CRT and 26% of BiV-CRT. The most common reason for crossover from His-CRT was inability to correct QRS owing to nonspecific intraventricular conduction delay (n = 5). Patients treated with His-CRT demonstrated greater QRS narrowing compared to BiV (125 ± 22 ms vs 164 ± 25 ms TR, P < .001;124 ± 19 ms vs 162 ± 24 ms PP, P < .001). A trend toward higher echocardiographic response was also observed (80 vs 57% TR, P = .14; 91% vs 54% PP, P = .078). No significant differences in CV hospitalization or mortality were observed.
Patients receiving His-CRT on-treatment demonstrated superior electrical resynchronization and a trend toward higher echocardiographic response than BiV-CRT. Larger prospective studies may be justifiable with refinements in patient selection and implantation techniques to minimize crossovers.
The aim of this analysis was to provide comprehensive information on invasive cardiac arrhythmia therapies in the European Society of Cardiology (ESC) area over the past 10 years.
The European Heart ...Rhythm Association (EHRA) has collected data on invasive arrhythmia therapies since 2008. This year 53 of the 56 ESC member countries provided data for the EHRA White Book. Here we present updated data on procedure rates together with information on demographics, economy, vital statistics, local healthcare systems and training activities. Considerable heterogeneity in the access to invasive arrhythmia therapies still exists across the five geographical ESC regions. In 2016, the device implantation rates per million population were 3-6 times higher in the Western region than in the non-European and Eastern ESC member countries. Catheter ablation activity was highest in the Western countries followed by the Northern and Southern areas. In the non-European countries, atrial fibrillation ablation rate was more than tenfold lower than in the European countries. On the other hand, the growth rate over the past ten years was highest in the non-European and Eastern countries. In some Eastern European countries with relative low gross domestic product the procedure rates exceeded the average values.
It was encouraging to note that during the past decade the growth in invasive arrhythmia therapies was greatest in the areas historically with relatively low activity. Nevertheless, there is substantial disparity and continued efforts are needed to improve harmonization of cardiac arrhythmia therapies in the ESC area.
This study sought to assess the impact of targeted left ventricular (LV) lead placement on outcomes of cardiac resynchronization therapy (CRT).
Placement of the LV lead to the latest sites of ...contraction and away from the scar confers the best response to CRT. We conducted a randomized, controlled trial to compare a targeted approach to LV lead placement with usual care.
A total of 220 patients scheduled for CRT underwent baseline echocardiographic speckle-tracking 2-dimensional radial strain imaging and were then randomized 1:1 into 2 groups. In group 1 (TARGET Targeted Left Ventricular Lead Placement to Guide Cardiac Resynchronization Therapy), the LV lead was positioned at the latest site of peak contraction with an amplitude of >10% to signify freedom from scar. In group 2 (control) patients underwent standard unguided CRT. Patients were classified by the relationship of the LV lead to the optimal site as concordant (at optimal site), adjacent (within 1 segment), or remote (≥2 segments away). The primary endpoint was a ≥15% reduction in LV end-systolic volume at 6 months. Secondary endpoints were clinical response (≥1 improvement in New York Heart Association functional class), all-cause mortality, and combined all-cause mortality and heart failure-related hospitalization.
The groups were balanced at randomization. In the TARGET group, there was a greater proportion of responders at 6 months (70% vs. 55%, p = 0.031), giving an absolute difference in the primary endpoint of 15% (95% confidence interval: 2% to 28%). Compared with controls, TARGET patients had a higher clinical response (83% vs. 65%, p = 0.003) and lower rates of the combined endpoint (log-rank test, p = 0.031).
Compared with standard CRT treatment, the use of speckle-tracking echocardiography to the target LV lead placement yields significantly improved response and clinical status and lower rates of combined death and heart failure-related hospitalization. (Targeted Left Ventricular Lead Placement to Guide Cardiac Resynchronization Therapy TARGET study); ISRCTN19717943).
Response to cardiac resynchronization therapy (CRT) remains challenging. Pacing from multiple sites of the left ventricle (LV) has shown promising results.
The purpose of this study was to ...systematically compare the acute hemodynamic effects of multipoint pacing (MPP) by means of a quadripolar lead with conventional biventricular (BiV) pacing.
Twenty-nine patients (23 men; mean age 72 ± 12 years; LV ejection fraction 29% ± 7%; 15 with ischemic cardiomyopathy, 17 with left bundle branch block; mean QRS 183 ± 23 ms) underwent CRT implantation. Per patient, 3.2 ± 1.2 different veins and 6.3 ± 2.4 pacing sites were tested. LV electrical delay (Q-LV) was measured at each location, along with the increase in LV dP/dtmax (maximum rate of rise of LV pressure) obtained by BiV and MPP. The effect of MPP, by means of simultaneous pacing from distal and proximal dipoles, was investigated at all available sites.
Overall, 3.2 ± 1.2 different MPP measurements were collected per patient. When all sites were considered, LV dP/dtmax increased from 951 ± 193 mm Hg/s at baseline to 1144 ± 255 and 1178 ± 259 mm Hg/s on BiV and MPP, respectively. When the best site was considered, LV dP/dtmax increased from a baseline value of 942 ± 202 mm Hg/s to 1200 ± 267 mm Hg/s (BiV) and 1231 ± 267 mm Hg/s (MPP). The mean QRS duration at any site during MPP and conventional CRT was 171 ± 18 and 175 ± 16 ms (P = .003), respectively.
Compared with BiV pacing at any LV site, MPP yielded a small but consistent increase in hemodynamic response. A correlation between the increase in hemodynamics and Q-LV on MPP was observed for all measurements, including those taken at the best and worst sites. The MPP-induced improvement in contractility was associated with significantly greater narrowing of the QRS complex than conventional BiV pacing.
Aim To assess incidence, predisposing factors and outcomes of cardiac device-related infective endocarditis (CDRIE) in patients undergoing cardiac resynchronization therapy (CRT). Methods and Results ...High-volume, single-center cardiology database was screened to identify all CDRIE cases, based on modified Duke criteria, amongst 765 consecutive CRT implantations between 2002 and 2015 (70.8% de novo implantations, 13.7% and 15.5% up-grades from pacemaker and implantable cardioverter-defibrillator ICD, respectively). During the median follow-up (FU) of 1207 days (range:256–2664) overall 38 CDRIE (4.97%) cases were identified (incidence: 15/1000 person-years). Multivariate Cox regression model, incorporating significant baseline differences as covariates (model 1), demonstrated that both up-grade from ICD to CRT and higher baseline NYHA class were independently associated with increased risk of CDRIE (adjusted HR 4.29, 95%CI 1.93–9.57; and HR 2.43, 95%CI 1.32–4.49, respectively). In the second model (including all differences with P < 0.2) up-grade from ICD (HR 4.36, 95%CI 1.96–9.69), higher NYHA class (HR 2.04, 95%CI 1.11–3.75), hypertrophic cardiomyopathy (HR 5.85, 95% CI 1.46–23.52), lower baseline hemoglobin level (HR 0.68, 95%CI 0.50–0.94) and chronic obstructive pulmonary disease (HR 2.46, 95%CI 1.05–5.77) were all independently associated with higher risk of CDRIE. All-cause mortality in patients with CDRIE was significantly higher than in subjects without infective complications (68.4% vs. 33.7%, P < 0.001), and 50% of patients with CDRIE died during index hospitalization. Conclusions The prevalence of CDRIE in CRT recipients is almost 5% within 3.5 years post implantation. Up-grade from ICD and high baseline NYHA class flag up patients at high-risk of CDRIE. CRT-related infective complications are associated with very poor prognosis.
Remote management of heart failure using implantable electronic devices (REM-HF) aimed to assess the clinical and cost-effectiveness of remote monitoring (RM) of heart failure in patients with ...cardiac implanted electronic devices (CIEDs).
Between 29 September 2011 and 31 March 2014, we randomly assigned 1650 patients with heart failure and a CIED to active RM or usual care (UC). The active RM pathway included formalized remote follow-up protocols, and UC was standard practice in nine recruiting centres in England. The primary endpoint in the time to event analysis was the 1st event of death from any cause or unplanned hospitalization for cardiovascular reasons. Secondary endpoints included death from any cause, death from cardiovascular reasons, death from cardiovascular reasons and unplanned cardiovascular hospitalization, unplanned cardiovascular hospitalization, and unplanned hospitalization. REM-HF is registered with ISRCTN (96536028). The mean age of the population was 70 years (range 23-98); 86% were male. Patients were followed for a median of 2.8 years (range 0-4.3 years) completing on 31 January 2016. Patient adherence was high with a drop out of 4.3% over the course of the study. The incidence of the primary endpoint did not differ significantly between active RM and UC groups, which occurred in 42.4 and 40.8% of patients, respectively hazard ratio 1.01; 95% confidence interval (CI) 0.87-1.18; P = 0.87. There were no significant differences between the two groups with respect to any of the secondary endpoints or the time to the primary endpoint components.
Among patients with heart failure and a CIED, RM using weekly downloads and a formalized follow up approach does not improve outcomes.
Candidates for cardiac resynchronization therapy (CRT) receive either a biventricular pacemaker or a biventricular pacemaker with an implantable cardioverter-defibrillator (CRT-D). Optimal device ...selection remains challenging because the benefit of implantable cardioverter-defibrillator therapy may not be uniform, particularly in patients at competing risk of nonsudden death.
In this serial cross-sectional study using the National Inpatient Sample database, we identified 311,086 admissions associated with CRT implant between 2006 to 2012. CRT-D was the most common device type (86.1%), including in patients ≥ 75 years of age with ≥ 5 Elixhauser comorbidities (75.5%). Multivariate predictors of CRT-D implant included demographic, clinical, and geographic factors: prior ventricular arrhythmia (rate ratio RR, 1.14; 95% CI, 1.13-1.14), ischemic heart disease (RR, 1.11; 95% CI, 1.10-1.11), male sex (RR, 1.10; 95% CI, 1.09-1.10), black race (RR, 1.06; 95% CI: 1.04-1.07), and Northeast geographic region (RR, 1.06; 95% CI, 1.04-1.09). There was significant interhospital variation in the use of CRT-D (10-90 percentile range, 72.9%-98.0% CRT-D).
The majority of patients in this contemporary US cohort underwent implantation of CRT-D. Predictors of CRT-D implant included demographic, clinical, and geographic factors. In patient subgroups predicted to have an attenuated benefit from implantable cardioverter-defibrillator therapy (older adults with multiple comorbidities), CRT-D remained the dominant device type. An improved understanding of the determinants of device selection may aid in decision making and ultimately better align patient risk with device benefit at the time of CRT implantation.