Cardiac Resynchronization Therapy Defibrillator Implantation Research Articles

Chronic electrical performance of a new ultra-thin left ventricular quadripolar pacing lead

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): H2020-FTI [Fast Track to Innovation] Pilot-2016 and MicroPort CRM Background Left ventricular (LV) lead positioning is an important contributor to cardiac resynchronization therapy (CRT) response. Multiple additional LV sites could be stimulated by passing a new ultra-thin (1.2 Fr, 0.4 mm) quadripolar microlead from one LV vein into another via venous collaterals. Purpose Study the acute and chronic stability and electrical pacing performance of a novel 1.2 Fr quadripolar microlead ("Axone 4LV"). Methods Seven healthy adult dogs underwent CRT defibrillator implantation, including a right ventricular lead and the microlead. The microlead was advanced into the coronary sinus network using a dedicated microguide catheter. The animals were followed up at 1, 15, 30 and 90 days post-implant to evaluate chronic stability and electrical pacing performance. Results Successful uncomplicated implantation was achieved in all cases. Despite the small diameter of the distal veins and collaterals, placement of the pacing electrodes in two different LV veins was feasible via available collateral passages. Lead position was stable in all cases and over the entire study period. Capture threshold and pacing impedance at 90 days post-implant were 1.7 ± 0.5 V with 1323 ± 245 Ω, respectively, at 0.5 ms pulse width. The mean pacing energy to get capture was 1.1 ± 0.5 µJ and less than 2 µJ in all cases (2 µJ ≈ 1.4 V @500 Ω, 0.5 ms). No phrenic nerve stimulation was observed during pacing. Conclusions The novel 1.2 Fr quadripolar microlead demonstrated adequate stability and good electrical performance allied to low energy consumption. This quadripolar microlead may extend pacing options while increasing device longevity in CRT. Changes in pacing parameters over time Post-implant Follow-up Pacing Threshold Pacing Impedance Pacing Energy 1 day 1.4 ± 0.7 V 1294 ± 270 Ω 0.8 ± 0.7 µJ 15 days 1.9 ± 0.9 V 1336 ± 274 Ω 1.8 ± 1.8 µJ 30 days 1.8 ± 0.7 V 1187 ± 303 Ω 1.5 ± 1.2 µJ 90 days 1.7 ± 0.5 V 1323 ± 245 Ω 1.1 ± 0.5 µJ

Hemodynamic monitoring by intracardiac impedance measured by cardiac resynchronization defibrillators: Evaluation in a controlled clinical setting (BIO.Detect HF II study)

BackgroundIn patients with cardiac resynchronization therapy defibrillators (CRT-Ds), intracardiac impedance measured by dedicated CRT-D software may be used to monitor hemodynamic changes. We investigated the relationship of hemodynamic parameters assessed by intracardiac impedance and by echocardiography in a controlled clinical setting. MethodsThe study enrolled 68 patients (mean age, 66 ± 9 years; 74% males) at 12 investigational sites. The patients had an indication for CRT-D implantation, New York Heart Association class II/III symptoms, left ventricular ejection fraction 15%–35%, and a QRS duration ≥150 ms. Two months after a CRT-D implantation, hemodynamic changes were provoked by overdrive pacing. Intracardiac impedance was recorded at rest and at four pacing rates ranging from 10 to 40 beats/min above the resting rate. In parallel, echocardiography measurements were performed. We hypothesized that a mean intra-individual correlation coefficient (rmean) between stroke impedance (difference between end-systolic and end-diastolic intracardiac impedance) measured by CRT-D and the aortic velocity time integral (i.e., stroke volume) determined by echocardiography would be significantly larger than 0.65. ResultsThe hypothesis was evaluated in 40 patients with complete data sets. The rmean was 0.797, with a lower confidence interval bound of 0.709. The study hypothesis was met (p = 0.007). A stepwise reduction of stroke impedance and stroke volume was observed with increasing heart rate. ConclusionsIntracardiac impedance measured by implanted CRT-Ds correlated well with the aortic velocity time integral (stroke volume) determined by echocardiography. The impedance measurements bear potential and are readily available technically, not requiring implantation of additional material beyond standard CRT-D system.

Residual versus recurrent mitral regurgitation after transcatheter mitral valve edge-to-edge repair.

The number of MtraClip procedures is increasing, and consequently, the number of patients with residual or recurrent mitral regurgitation (MR). We aimed to characterize patients who had residual versus recurrent MR after MitraClip and report the outcomes of different treatment strategies. From 2012 to 2020, 167 patients had MitraClip. Out of them, 16 patients (9.5%) had residual mitral regurgitation (MR), and 27 patients (16.2%) had recurrent MR. The median age in patients with residual MR was 67.5 (59-73) years versus 69 (61-78) years in patients with recurrent MR (p = .87). The etiology of mitral valve disease was functional in 13 patients (81.3%) and 22 patients (84.6%) in residual versus recurrent MR patients (p > .99). Cardiac resynchronization therapy-defibrillator implantation was higher in patients with residual MR (p = .02). Survival was 93.7% at 1 year, 76.4% at 3 years versus 92.5% at 1 year, and 84.5% at 3 years in residual versus recurrent MR (p = .69). Two patients in the residual MR group had re-clip, and three had surgery, and in the recurrent MR group, one patient had re-clip, and two patients had surgery (p = .23). Patients who had re-clip were older (p = .09). Surgery was associated with 100% survival at 5 years, 63% after medical therapy and the worst survival was reported in re-clip patients (p = .007). The outcomes of patients with residual versus recurrent mitral regurgitation after MitraClip were comparable. Survival could be improved with surgery compared with medical therapy and re-clip.

Multi-lead cephalic venous access and long-term performance of high-voltage leads.

Cardiac resynchronization therapy-defibrillator (CRT-D) implantation via the cephalic vein is feasible and safe. Recent evidence has suggested a higher implantable cardioverter-defibrillator (ICD) lead failure in multi-lead defibrillator therapy via the cephalic route. We evaluated the relationship between CRT-D implantation via the cephalic and ICD lead failure. Data was collected from three CRT-D implanting centers between October 2008 and September 2017. In total 633 patients were included. Patient and lead characteristics with ICD lead failure were recorded. Comparison of "cephalic" (ICD lead via cephalic) versus "non-cephalic" (ICD lead via non-cephalic route) cohorts was performed. Kaplan-Meier survival and a Cox-regression analysis were applied to assess variables associated with lead failure. The cephalic and non-cephalic cohorts were equally male (81.9% vs. 78%; p = .26), similar in age (69.7 ± 11.5 vs. 68.7 ± 11.9; p = .33) and body mass index (BMI) (27.7 ± 5.1 vs. 27.1 ± 5.7; p = .33). Most ICD leads were implanted via the cephalic vein (73.5%) and patients had a mean of 2.9 ± 0.28 leads implanted via this route. The rate of ICD lead failure was low and statistically similar between both groups (0.36%/year vs. 0.13%/year; p = .12). Female gender was more common in the lead failure cohort than non-failure (55.6% vs. 17.9%, respectively; p = .004) as was hypertension (88.9% vs. 54.2%, respectively, p = .038). On multivariate Cox-regression, female sex (p = .008; HR, 7.12 [1.7-30.2]), and BMI (p = .047; HR, 1.12 [1.001-1.24]) were significantly associated with ICD lead failure. CRT-D implantation via the cephalic route is not significantly associated with premature ICD lead failure. Female gender and BMI are predictors of lead failure.

Use and Outcomes of Dual Chamber or Cardiac Resynchronization Therapy Defibrillators Among Older Patients Requiring Ventricular Pacing in the National Cardiovascular Data Registry Implantable Cardioverter Defibrillator Registry

Frequent right ventricular (RV) pacing can cause and exacerbate heart failure. Cardiac resynchronization therapy (CRT) has been shown to be associated with improved outcomes among patients with reduced left ventricular ejection fraction who need frequent RV pacing, but the patterns of use of CRT vs dual chamber (DC) devices and the associated outcomes among these patients in clinical practice is not known. To assess outcomes, variability in use of device type, and trends in use of device type over time among patients undergoing implantable cardioverter defibrillator (ICD) implantation who were likely to require frequent RV pacing but who did not have a class I indication for CRT. This retrospective cohort study used the National Cardiovascular Data Registry (NCDR) ICD Registry. A total of 3100 Medicare beneficiaries undergoing first-time implantation of CRT defibrillator (CRT-D) or DC-ICD from 2010 to 2016 who had a class I or II guideline ventricular bradycardia pacing indication but not a class I indication for CRT were included. Data were analyzed from August 2018 to October 2019. Implantation of a CRT-D or DC-ICD. All-cause mortality, heart failure hospitalization, and complications were ascertained from Medicare claims data. Multivariable Cox proportional hazards models and Fine-Gray models were used to evaluate 1-year mortality and heart failure hospitalization, respectively. Multivariable logistic regression was used to evaluate 30-day and 90-day complications. All models accounted for clustering. The median odds ratio (MOR) was used to assess variability and represents the odds that a randomly selected patient receiving CRT-D at a hospital with high implant rates would receive CRT-D if they had been treated at a hospital with low CRT-D implant rates. A total of 3100 individuals were included. The mean (SD) age was 76.3 (6.4) years, and 2500 (80.6%) were men. The 1698 patients (54.7%) receiving CRT-D were more likely than those receiving DC-ICD to have third-degree atrioventricular block (828 [48.8%] vs 432 [30.8%]; P < .001), nonischemic cardiomyopathy (508 [29.9%] vs 255 [18.2%]; P < .001), and prior heart failure hospitalizations (703 [41.4%] vs 421 [30.0%]; P < .001). Following adjustment, CRT-D was associated with lower 1-year mortality (hazard ratio [HR], 0.70; 95% CI, 0.57-0.87; P = .001) and heart failure hospitalization (subdistribution HR, 0.77; 95% CI, 0.61-0.97; P = .02) and no difference in complications compared with DC-ICD. Hospital variation in use of CRT was present (MOR, 2.00), and the use of CRT in this cohort was higher over time (654 of 1351 [48.4%] in 2010 vs 362 of 594 [60.9%] in 2016; P < .001). In this cohort study of older patients in contemporary practice undergoing ICD implantation with a bradycardia pacing indication but without a class I indication for CRT, CRT-D was associated with better outcomes compared with DC devices. Variability in use of device type was observed, and the rate of CRT implantation increased over time.

Association Between Industry Payments to Physicians and Device Selection in ICD Implantation

Little is known about the association between industry payments and medical device selection. To examine the association between payments from device manufacturers to physicians and device selection for patients undergoing first-time implantation of a cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D). In this cross-sectional study, patients who received a first-time ICD or CRT-D device from any of the 4 major manufacturers (January 1, 2016-December 31, 2018) were identified. The data from the National Cardiovascular Data Registry ICD Registry was linked with the Open Payments Program's payment data. Patients were categorized into 4 groups (A, B, C, and D) corresponding to the manufacturer from which the physician who performed the implantation received the largest payment. For each patient group, the proportion of patients who received a device from the manufacturer that provided the largest payment to the physician who performed implantation was determined. Within each group, the absolute difference in proportional use of devices between the manufacturer that made the highest payment and the proportion of devices from the same manufacturer in the entire study cohort (expected prevalence) was calculated. Manufacturers' payments to physicians who performed an ICD or CRT-D implantation. The primary outcome of the study was the manufacturer of the device used for the implantation. Over a 3-year period, 145 900 patients (median age, 65 years; 29.6% women) received ICD or CRT-D devices from the 4 manufacturers implanted by 4435 physicians at 1763 facilities. Among these physicians, 4152 (94%) received payments from device manufacturers ranging from $2 to $323 559 with a median payment of $1211 (interquartile range, $390-$3702). Between 38.5% and 54.7% of patients received devices from the manufacturers that had provided physicians with the largest payments. Patients were substantially more likely to receive devices made by the manufacturer that provided the largest payment to the physician who performed implantation than they were from each other individual manufacturer. The absolute differences in proportional use from the expected prevalence were 22.4% (95% CI, 21.9%-22.9%) for manufacturer A; 14.5% (95% CI, 14.0%-15.0%) for manufacturer B; 18.8% (95% CI, 18.2%-19.4%) for manufacturer C; and 30.6% (95% CI, 30.0%-31.2%) for manufacturer D. In this cross-sectional study, a large proportion of ICD or CRT-D implantations were performed by physicians who received payments from device manufacturers. Patients were more likely to receive ICD or CRT-D devices from the manufacturer that provided the highest total payment to the physician who performed an ICD or CRT-D implantation than each other manufacturer individually.

CLINICAL CASE OF NON-COMPACTION CARDIOMYOPATHY IN A PATIENT WITH PKP2 GENE MUTATION

The features of the clinical course of non-compaction cardiomyopathy, its prognosis and even its diagnosis are still the subject of discussion. The variety of phenotypes of this disease and genetic heterogeneity dictates the need for detailed clinical and molecular genetic examination of patients with this pathology. The article presents a clinical observation of a patient with a dilated phenotype of left ventricular non-compaction, progression of chronic heart failure, as well as the presence of ventricular rhythm and conduction disorders that required the implantation of cardiac resynchronization therapydefibrillator (CRT-D). The patient was found to have a missense mutation c. 1892A&gt;G (p.Tyr631Cys, rs1060501183) in PKP2 gene in a heterozygous state. The issues of differential diagnostics with arrhythmogenic right ventricular cardiomyopathy and treatment strategies for the disease were discussed.

Relationship between device-detected subclinical atrial fibrillation and heart failure in patients with cardiac resynchronization therapy defibrillator.

BackgroundAtrial fibrillation (AF) is a leading preventable cause of heart failure (HF) for which early detection and treatment is critical. Subclinical‐AF is likely to go untreated in the routine care of patients with cardiac resynchronization therapy defibrillator (CRT‐D).HypothesisThe hypothesis of our study is that subclinical‐AF is associated with HF hospitalization and increasing an inappropriate therapy.MethodsWe investigated 153 patients with an ejection fraction less than 35%. We divided into three groups, subclinical‐AF (n = 30), clinical‐AF (n = 45) and no‐AF (n = 78). We compared the baseline characteristics, HF hospitalization, and device therapy among three groups. The follow‐up period was 50 months after classification of the groups.ResultsThe average age was 66 ± 15 years and the average ejection fraction was 26 ± 8%. Inappropriate therapy and biventricular pacing were significantly different between subclinical‐AF and other groups (inappropriate therapy: subclinical‐AF 13% vs clinical‐AF 8.9% vs no‐AF 7.7%: P = .04, biventricular pacing: subclinical‐AF 81% vs clinical‐AF 85% vs no‐AF 94%, P = .001). Using Kaplan‐Meier method, subclinical‐AF group had a significantly higher HF hospitalization rate as compared with other groups. (subclinical‐AF 70% vs clinical‐AF 49% vs no‐AF 38%, log‐rank: P = .03). In multivariable analysis, subclinical‐AF was a predictor of HF hospitalization.ConclusionsSubclinical‐AF after CRT‐D implantation was associated with a significantly increased risk of HF hospitalization. The loss of the biventricular pacing and increasing an inappropriate therapy might affect the risk of HF hospitalization.

Patient responses to daily cardiac resynchronization therapy device data: A pilot trial assessing a novel patient-centered digital dashboard in everyday life

BackgroundHeart failure (HF) is a growing public health problem in the United States. Implantable cardiac resynchronization therapy (CRT) devices reduce mortality and morbidity, and remote monitoring (RM) of these devices improves outcomes. However, patient RM adherence is low, due in part to lack of access to their RM data. Providing these data to patients may increase engagement, but they must be appropriately tailored to ensure understanding.ObjectiveThe purpose of this study was to examine patients’ experiences interacting with their RM data through a novel digital dashboard as part of daily life.MethodsIn this mixed-methods pilot study, 10 patients with implantable CRT defibrillators were given access to a patient-centered RM data dashboard, updated daily for 6–12 months. Pre- and post-health literacy, engagement, electronic portal (MyChart, Epic Systems Corporation) logins, and RM adherence were measured; system usability scores were collected at exit; and dashboard views were tracked. Exit interviews were conducted to elucidate patients’ experiences.ResultsParticipants (100% white; 60% male; age 34–80 years [mean ± SD: 62.0 ± 13.4]) had adequate health literacy, increased MyChart logins (P = .0463), and nonsignificant increase in RM adherence. Participants viewed their dashboards 0–42 times (mean 14.9 ± 12.5). Interviews revealed participants generally appreciated access to their data, understood it, and responded to changes; however, questions and concerns remained regarding data interpretation and visualization.ConclusionPreliminary findings support potential future integration of a CRT RM data dashboard in the daily care of HF patients. With appropriate informational support and personalization, sharing RM data with patients in a tailored dashboard may improve health engagement.

The incidence and survival after in-hospital cardiopulmonary cerebral resuscitation in end-stage kidney disease patients: A nationwide population-based study.

This study analyzed the survival and protective predictors of in-hospital cardiopulmonary cerebral resuscitation (CPCR) to potentially help physicians create effective treatment plans for End-stage kidney disease (ESKD) patients. We extracted the data of 7,116 ESKD patients who received their first in-hospital CPCR after initial dialysis between 2004 and 2012 from the National Health Insurance Research Database. The primary outcome was the survival rate during the first in-hospital CPCR. The secondary outcome was the median post-discharge survival. From 2004 through 2012, the incidence of in-hospital CPCR decreases from 3.97 to 3.67 events per 1,000 admission days (P for linear trend <0.001). The survival rate for the first in-hospital CPCR did not change significantly across the 9 years (P for trend = 0.244), whereas the median survival of post-discharge survival increased significantly from 3.0 months in 2004 to 6.8 months in 2011 (P for linear trend <0.001). In addition, multivariable analysis identified older age as a risk factor and prior intracardiac defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) implantation as a protective factor for in-hospital death during the first in-hospital CPCR. The incidence of in-hospital CPCR and the duration post-discharge among ESKD patients improved despite there being no significant difference in the survival rate of ESKD patients after CPCP. Either ICD or CRT-D implantation may be advisable for ESKD patients with a high risk of sudden cardiac death.

Association of Implantable Device Measured Physical Activity With Hospitalization for Heart Failure

ObjectivesThe purpose of this study was to evaluate the association of physical activity (PA) level and longitudinal PA trajectory with a composite heart failure hospitalization and mortality endpoint over a 5-year follow-up period following implantation. BackgroundLow device measured PA early after implantation of an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) is associated with poor outcomes. MethodsWe linked daily PA data from the Boston Scientific ALTITUDE dataset of patients with ICD or CRT-D implantation to Medicare claims data. We used a joint model to investigate the association of the composite endpoint with 1) the time-varying point estimate of PA and 2) the time-varying trajectory/slope of PA during follow-up. ResultsAmong 20,927 patients with median activity level 85 min/day, 14.1% and 49.6% experienced the composite endpoint at 1 and 5 years. Adjusted joint model results showed that there was a 1.13 (95% confidence interval: 1.12 to 1.13)-fold increase in the hazard of the composite endpoint for 75 min of daily PA relative to 85 min of PA; and a within-patient 10-min decrease in average daily PA over an 8-week period from 85 to 75 min was associated with a hazard ratio of 4.02 (95% confidence interval: 3.82 to 4.22) for the composite endpoint. ConclusionsPatients with large decreases in PA have significantly higher risk of experiencing heart failure hospitalization or death. PA data from implantable devices may identify patients before clinical decompensation.

P1260 Chagas disease, a new challenge to the old continent

Abstract Case Report A 53-year-old female patient from the North Region of Brazil with a past medical history of Chagas Disease (CD) with esophageal involvement and permanent atrial fibrillation (AF) presented to the Emergency Department (ED) due to complaints of retrosternal discomfort and dizziness. The patient reported multiple recent syncopal episodes and had performed a recent 24-hour Holter monitoring revealing AF with predominantly slow ventricular rate and frequent ventricular premature beats. Her sister had recently been diagnosed with obstructive hypertrophic cardiomyopathy. During the ED stay, the patient developed a syncopal monomorphic ventricular tachycardia, requiring synchronized electrical cardioversion. Post cardioversion EKG revealed a sinus rhythm with a right bundle branch block, left anterior fascicular block and 1st degree AV block. The patient was admitted in the Cardiology Department for further investigation. Transthoracic echocardiogram revealed a dilated left ventricle with a reduced systolic function (LVEF of 38%, GLS of -7.1%), with an aneurysm of the basal inferior and posterior walls and a markedly dilated left atrium (68mL/m2). Cardiac magnetic resonance imaging showed a marked dilation of both atriums and ventricles, with biventricular systolic dysfunction, hypertrabeculation of the left ventricular wall and the presence of diffuse intramural and subepicardic fibrosis. These features were compatible with chagasic cardiomyopathy. Due to biventricular systolic dysfunction, the documentation of AV conduction disturbance, the natural history of the disease and the need for antiarrhythmic therapy, the patient underwent cardiac resynchronization therapy–defibrillator implantation. 1 week after the procedure, the patient experienced an arrhythmic storm with a total of 6 CRT-D shocks. Amiodarone was initiated and beta-blocker was titulated to the maximum tolerated dose, with no recurrence of ventricular tachycardia. On the 3 month follow-up visit the patient denied symptoms of congestive heart failure. Device interrogation revealed a high percentage of biventricular pacing and no arrhythmic events. Conclusion This case describes the most remarkable and characteristic features of chagasic cardiomyopathy. It is almost always progressive and is associated with a worse outcome comparing with other cardiomyopathies. The prevalence of CD is growing in traditionally nonendemic areas and its timely recognition is fundamental.

P287015 year trend in ICD utilization according to the Italian national administrative database: an analysis of age groups

Abstract To achieve a complete coverage of all Implantable Cardioverter Defibrillator (ICD) performed in Italy between 2001 and 2015, data from the National Hospital Discharge Database (SDO: “Scheda di Dimissione Ospedaliera”) were analyzed. Frequencies and implant rate of ICD and Cardiac Resynchronization Therapy/Defibrillator (CRTD) according to the Italian population were computed. Data were analyzed for the following age classes: &lt;50, 50–80, &gt;80. Results Total number of ICD increased from 3141 in 2001 (implant rate 54/million inhabitants) to 23.540 in 2015 (387/million). From 2009 to 2015 CRT-D increased from 2916 in 2009 (49/million) to 8245 in 2015 (136/million), while the proportion of CRT/total ICD from 17% to 35%. Mean age (from 67±12 in 2001 to 68±12 in 2015) and the proportion of males (from 80% to 79%) remained unchanged. Ischemic heart disease was the most frequent diagnosis (55.6% in 2001, 45.4% in 2015). ICD for secondary prevention have been reducing from 55.6% to 13.6% (ventricular tachycardia, VT) and from 18.1% to 5.9% (ventricular fibrillation, VF). The proportion of patients with heart failure (from 23.9% to 47.9%), hypertension (from 11.2% to 16.2%), diabetes mellitus (6.5% to 11.6%) and renal insufficiency (from 4.4% to 8%) increased. The proportion of CRT/ICD remained constant (except for the 2009, where a possible underdiagnosis is very likely), between 43% and 39%. In patients &lt;50 years old the number of ICD increased from 367 (10/million) in 2001 to 1829 (52/million) in 2015; the most frequent diagnosis was idiopathic cardiomyopathy (30%), while ischemic heart disease was present in 20%. An increase of the proportion of patients with the diagnosis of heart failure (from 13.8% to 33.6%), hypertension (from 4.3% to 8.5%), diabetes mellitus (1.5% to 3.9%) and renal insufficiency (from 1.3% to 2.2%) was observed. In patients &gt;80 years old the number of ICD increased from 195 (82/million) in 2001 to 3902 (981/million) in 2015; ischemic heart disease was the most frequent diagnosis (53.8% in 2001, 43.5% in 2015). ICD for secondary prevention reduced from 50.3% to 14,8% (VT) and from 16.4% to 4.1% (VF), with an increase of the proportion of patients with heart failure (from 22.6% to 46.3%), hypertension (from 11.8% to 17.1%), diabetes mellitus (5.6% to 9.9%) and renal insufficiency (from 7.2% to 12.1%). Conclusions There was a steady increase of ICD and CRTD implantation during the last fifteen years, especially in those &gt;80 years; the proportion of patients treated for secondary prevention dramatically reduced since early 2000; an increase of co-morbidities was observed.

Validation of an apnea and hypopnea detection algorithm implemented in implantable cardioverter defibrillators. The AIRLESS study

Diagnosis of sleep apnea (SA) using simple tools has the potential to improve the efficacy of cardiac implants in the prevention of cardiac arrhythmias. The aim of the present study was to validate a transthoracic impedance sensor for SA diagnosis in patients with cardiac implants. We compared the apnea-hypopnea index (AHI) obtained from polysomnography (AHIPSG) with the AHI obtained from autoscoring algorithms of the ApneaScan implantable impedance respiration sensor (AHIAS) three months after implantation of cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) devices. Twenty-five patients with indications for implantation of ICD or CRT-D (INCEPTA; Boston Scientific) (24 men, 59.9 ± 14.4 years; LVEF 30.3 ± 6.4%; body mass index 25.9 ± 4.2 kg/m²) were included. Mean AHI-PSG was 21.9 ± 19.1 events/hr. A significant correlation was found between AHIPSG and AHIAS especially for the most severe SA (Spearman correlation: 0.71, p < 0.001). Intraclass Correlation Coefficient (was in the expected range: 0.67, 95% CI: 0.39–0.84. The mean bias was 5.4 events per hour (mean AHI: 23.3 ± 14.6 versus 29.7 ± 13.7 for AHI-PSG and AHI-AS, respectively). An optimal cutoff value for the AHIAS at 30 events/h was obtained from the Receiver Operator Characteristic (ROC) curve analysis, which yielded a sensitivity of 100%, a specificity of 80%, PPV = 67%, NPV = 100%. Using an advanced algorithm for autoscoring of transthoracic impedance included in ICDs is reliable to identify SA and has the potential to improve the management of patients with cardiac implants.

Frequency of in-hospital adverse outcomes and cost utilization associated with cardiac resynchronization therapy defibrillator implantation in the United States.

The utilization of cardiac resynchronization therapy defibrillator (CRT-D) has increased significantly, since its initial approval for use in selected patients with heart failure. Limited dataexist as for current trends in implant-related in-hospital complications and cost utilization. The aim of our study was to examine in-hospital complication rates associated with CRT-D and their trends over the last decade. Using the Nationwide Inpatient Sample, we estimated 378 248 CRT-D procedures from 2003 to 2012. We investigated common complications, including mechanical, cardiovascular, pericardial complications (hemopericardium, cardiac tamponade, or pericardiocentesis), pneumothorax, stroke, vascular complications (consisting of hemorrhage/hematoma, incidents requiring surgical repair, and accidental arterial puncture), and in-hospital deaths described with CRT-D, defining them by the validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code. Mechanical complications (5.9%) were the commonest, followed by cardiovascular (3.6%), respiratory failure (2.4%), and pneumothorax (1.5%). Age (≥65 years), female gender (OR, 95% CI; P value) (1.08, 1.03-1.13; 0.001), and the Charlson score ≥3 (1.52, 1.45-1.60; <0.001) were significantly associated with increased mortality/complications. The overall complication rate in patients undergoing CRT-D has been increasing in the last decade. Age (≥65), female sex, and the Charlson score ≥3 were associated with higher complications. In patients who underwent CRT-D implantation, postoperative complications were associated with significant increases in cost.

Evaluation of QRS dispersion and its association withtachyarrhythmia events in patients with implantedcardiac resynchronization therapy defibrillator device

Introduction: Heart failure (HF) is one of the major problems of health system in the countries. In a subgroup of these patients, cardiac resynchronization therapy defibrillator (CRT-D) improves the quality of life by enhancing the function of the left ventricle (LV) and preventing of arrhythmias. The present study intends to discuss the effect of CRT-D on the QRS dispersion, as a predisposing factor to arrhythmias. Methods: 45 patients treated with CRT-D during 2012-2015 were enrolled in this study. QRS dispersion in various V-V delays was measured and its association with the incidence of arrhythmias, at least six months after insertion, was assessed. Results: The results showed that QRS dispersion in the intrinsic mode was significantly lower than the other modes of the CRT-D device (P < 0.001). Besides, it was revealed that mean QRS duration in the intrinsic mode had a higher association with arrhythmic events than max QRS duration. QRS dispersion after CRT-D implantation had a significant increase compared to the intrinsic mode. However, it did not correlate with the arithmetic events. Further decrease in the duration of QRS after CRT-D implantation improved arrhythmias. Conclusion: QRS dispersion after CRT-D implantation is not an indicative of arrhythmia risk, and a decrease in the duration of QRS had a more significant effect on the incidence of arrhythmias.

Surface electrogram-guided left ventricular lead placement improves response to cardiac resynchronization therapy.

ObjectiveFailure to select the optimal left ventricular (LV) segment for lead implantation is one of the most important causes of unresponsiveness to the cardiac resynchronization therapy (CRT). In our study, we aimed to investigate the echocardiographic and clinical benefits of LV lead implantation guided by an intraoperative 12-lead surface electrocardiogram (ECG) in patients with multiple target veins.MethodsWe included 80 [42 (62.5%) male] heart failure patients who successfully underwent CRT defibrillator (CRT-D) implantation. Patients were divided into two groups. In group 1, LV lead was positioned at the site with the shortest biventricular-paced (BiV-paced) QRS duration (QRSd), as intraprocedurally measured using surface ECG. In group 2 (control), we included patients who underwent the standard unguided CRT. ECG, echocardiogram, and functional status were evaluated before and 6 months after CRT implantation in all patients.ResultsIn group 1, BiV-paced QRSd measurements were successfully performed in 112 of 120 coronary sinus branches during CRT and an LV lead was successfully placed at the optimal site in all patients. Compared with group 2, group 1 had a significantly higher rate (85% vs. 50%, p=0.02) of response (>15% reduction in LV end-systolic volume) to CRT as well as a shorter QRSd (p<0.001) and a greater QRS shortening (∆QRS) associated with CRT compared with baseline (p<0.001). The mean New York Heart Association functional class was significantly improved in both groups, and no significant differences were found in clinical response to CRT (85% vs. 70%, p=0.181).ConclusionSurface ECG can be used to guide LV lead placement in patients with multiple target veins for improving response to CRT. Thus, it is a safe, feasible, and economic approach for CRT-D implantation.

Loss of cardiac resynchronization therapy in a patient with a biventricular implantable cardioverter-defibrillator

Here, we discuss the case of a man with a history of ischemic cardiomyopathy and cardiac resynchronization therapy defibrillator implantation, who presented to emergency department with decompensated heart failure due to the loss of resynchronization therapy. The reason for the malfunction was left ventricle upper rate interval lock-in due to inappropriate programming of the device.

Clinical decision tool for CRT-P vs. CRT-D implantation: Findings from PROSE-ICD.

BackgroundCardiac resynchronization therapy (CRT) devices reduce mortality through pacing-induced cardiac resynchronization and implantable cardioverter defibrillator (ICD) therapy for ventricular arrhythmias (VAs). Whether certain factors can predict if patients will benefit more from implantation of CRT pacemakers (CRT-P) or CRT defibrillators (CRT-D) remains unclear.Methods and resultsWe followed 305 primary prevention CRT-D recipients for the two primary outcomes of HF hospitalization and ICD therapy for VAs. Serum biomarkers, electrocardiographic and clinical variables were collected prior to implant. Multivariable analysis using Cox-proportional hazards model was used to fit the final models. Among 282 patients with follow-up outcome data, 75 (26.6%) were hospitalized for HF and 31 (11%) received appropriate ICD therapy. Independent predictors of HF hospitalization were atrial fibrillation (HR = 1.8 (1.1,2.9)), NYHA class III/IV (HR = 2.2 (1.3,3.6)), ejection fraction <20% (HR = 1.7 (1.1,2.7)), HS-IL6 >4.03pg/ml (HR = 1.7 (1.1,2.9)) and hemoglobin (<12g/dl) (HR = 2.2 (1.3,3.6)). Independent predictors of appropriate therapy included BUN >20mg/dL (HR = 3.0 (1.3,7.1)), HS-CRP >9.42mg/L (HR = 2.3 (1.1,4.7)), no beta blocker therapy (HR = 3.2 (1.4,7.1)) and hematocrit ≥38% (HR = 2.7 (1.03,7.0)). Patients with 0–1 risk factors for appropriate therapy (IR 1 per 100 person-years) and ≥3 risk factors for HF hospitalization (IR 23 per 100-person-years) were more likely to die prior to receiving an appropriate ICD therapy.ConclusionsClinical and biomarker data can risk stratify CRT patients for HF progression and VAs. These findings may help characterize subgroups of patients that may benefit more from the use of CRT-P vs. CRT-D systems.Trial registrationClinicalTrials.gov NCT00733590

Effects of Upgrade Versus De Novo Cardiac Resynchronization Therapy on Clinical Response and Long-Term Survival: Results from a Multicenter Study.

Benefits of cardiac resynchronization therapy (CRT) on morbidity and mortality in selected patients are well known. Although the number of upgrade procedures from single- or dual-chamber devices to CRT is increasing, there are only sparse data on the outcomes of upgrade procedures compared with de novo CRT. This study aimed to evaluate clinical response and survival in patients receiving de novo versus upgrade CRT defibrillator therapy. Prospectively collected outcome data were compared in patients undergoing de novo or upgrade CRT defibrillator implantation at 3 implant centers in Germany and Hungary. Clinical response was defined as an improvement by at least one New York Heart Association (NYHA) functional class. CRT implantation was performed in 552 consecutive patients of whom 375 underwent a de novo and 177 an upgrade procedure. Upgrade patients were more often implanted for secondary prevention, suffered more often from atrial fibrillation, chronic kidney disease, diabetes mellitus, and dyslipidemia, and had more often a non-LBBB (left bundle branch block) wide QRS complex, and lower left ventricular ejection fraction. Upgrade procedures were associated with a lower response rate compared to the de novo group (57% versus 69%, P univariate=0.008, P multivariate=0.021). During the follow-up of 37±28 months, survival was worse after upgrade compared with de novo CRT defibrillator implantations (hazard ratio, 1.65; 95% confidence interval, 1.22-2.24; P=0.001) even after careful adjustment for important baseline variables (adjusted hazard ratio, 1.68; 95% confidence interval, 1.20-2.34; P=0.002) and after propensity-score matching (propensity-adjusted hazard ratio, 1.79; 95% confidence interval, 1.08-2.95; P=0.023). Both clinical response and long-term survival were less favorable in patients undergoing CRT upgrade compared to de novo implantations.