Contemporary trends of leadless pacemaker implantation in the United States.

INTRODUCTION: Leadless pacemakers (LPM) have established themselves as the important therapeutic modality in management of selected patients with symptomatic bradycardia. To determine real-world utilization and in-hospital outcomes of LPM implantation since its approval by the Food and Drug Administration in 2016. METHODS: For this retrospective cohort study, data were extracted from the National Inpatient Sample database from the years 2016-2020. The outcomes analyzed in our study included implantation trends of LPM over study years, mortality, major complications (defined as pericardial effusion requiring intervention, any vascular complication, or acute kidney injury), length of stay, and cost of hospitalization. Implantation trends of LPM were assessed using linear regression. Using years 2016-2017 as a reference, adjusted outcomes of mortality, major complications, prolonged length of stay (defined as >6 days), and increased hospitalization cost (defined as median cost >34 098$) were analyzed for subsequent years using a multivariable logistic regression model. RESULTS: There was a gradual increased trend of LPM implantation over our study years (3230 devices in years 2016-2017 to 11 815 devices in year 2020, p for trend <.01). The adjusted mortality improved significantly after LPM implantation in subsequent years compared to the reference years 2016-2017 (aOR for the year 2018: 0.61, 95% CI: 0.51-0.73; aOR for the year 2019: 0.49, 95% CI: 0.41-0.59; and aOR for the year 2020: 0.52, 95% CI: 0.44-0.62). No differences in adjusted rates of major complications were demonstrated over the subsequent years. The adjusted cost of hospitalization was higher for the years 2019 (aOR: 1.33, 95% CI: 1.22-1.46) and 2020 (aOR: 1.69, 95% CI: 1.55-1.84). CONCLUSION: The contemporary US practice has shown significantly increased implantation rates of LPM since its approval with reduced rates of inpatient mortality.

Cardiac implantable electrical devices in patients with hypertrophic cardiomyopathy: single center implant data extracted from the Swedish pacemaker and ICD registry.

Objectives: To investigate cardiac implantable electrical device (CIED) first implants in patients with hypertrophic cardiomyopathy (HCM) in a Swedish tertiary university hospital. Design: Clinical and technical data on pacemaker, implantable cardioverter defibrillator (ICD), and cardiac resynchronization therapy (CRT) first implants performed in HCM patients at the Karolinska University Hospital from 2005 to 2016 were extracted from the Swedish Pacemaker and ICD Registry. Echocardiographic data were obtained by review of hospital recordings. Results: The number of first pacemaker implants in HCM patients was 70 (1.5% of total pacemaker implants). The mean age of HCM pacemaker patients was 71 ± 10 years. Pacemaker implants were almost uniformly distributed between genders. Dual-chamber pacemakers with or without CRT properties were prevalent (6 and 93%, respectively). The number of first ICD implants in HCM patients was 99 (5.1% of total ICD implants). HCM patients receiving an ICD were 53 ± 15 years and prevalently men (70%). Sixty-five (66%) patients were implanted for primary prevention. Dual-chamber ICDs with or without CRT were 21 and 65%, respectively. Obstructive HCM was present in 47% pacemaker patients and 25% ICD patients with available pre-implant echo. Conclusions: This retrospective registry-based study provides a picture of CIED first implants in HCM patients in a Swedish tertiary university hospital. ICDs were the most commonly implanted devices, covering 59% of CIED implants. HCM patients receiving a pacemaker or an ICD had different epidemiological and clinical profiles.

Trends in complete heart block after transcatheter aortic valve replacement: A population based analysis.

OBJECTIVES: To define the national rate of complete heart block (CHB) after transcatheter aortic valve replacement (TAVR) and its impact on procedural mortality, overall cost, and length of hospital stay. BACKGROUND: CHB leading to permanent pacemaker (PPM) implantation is one of the most common complications post TAVR. National data on the temporal trend of CHB post TAVR are lacking. METHODS: We queried the 2012-2014 National Inpatient Sample databases to identify all patients who underwent TAVR. Patients with preoperative pacemakers or implantable cardioverter-defibrillators were excluded. Association between CHB and outcomes, and overall trends in rate of CHB, PPM implantation, and inpatient mortality were examined. RESULTS: Of 35,500 TAVR procedures, 3,675 (10.4%) had CHB. Overall, occurrence of CHB significantly increased from 8.4% in 2012 to 11.8% in 2014 (adjusted OR per year: 1.23; 95% confidence interval [CI]: 1.17-1.29, P trend <0.001). During the same period, PPM implantation increased from 9.5 to 13.7% (adjusted OR per year: 1.22; 95% CI: 1.16-1.28, P trend <0.001). Patients with CHB had higher odds of in-hospital mortality when compared to patients without CHB (5.9% vs. 4.2%, adjusted OR: 1.32; 95% CI: 1.12-1.56; p = 0.001). Moreover, CHB was also associated with longer length of stay (LOS) and higher hospitalization cost. CONCLUSIONS: There was a significant increase in rates of CHB and PPM implantation over the study period. Development of CHB was associated with increased in-hospital mortality, LOS, and hospitalization cost.

Characteristics of and current practice patterns of pacing for high-degree atrioventricular block after transcatheter aortic valve implantation in comparison to surgical aortic valve replacement.

OBJECTIVE: We aimed to investigate the current practice patterns of permanent pacing, especially the timing of implantation, for high-degree AV block (HDAVB) following transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). BACKGROUND: Comparative data regarding current practice patterns of permanent pacing for HDAVB between TAVI and SAVR is limited. METHODS: Using the National Inpatient Sample database, we identified patients who underwent TAVI or SAVR between 2012 and 2014. The incidence of HDAVB, the rate of permanent pacemaker implantation, and the timing of implantations were compared between TAVI and SAVR groups. RESULTS: We identified 33 690 and 202 110 patients who underwent TAVI and SAVR, respectively. HDAVB occurred in 3480 patients (10.3%) in the TAVI group and 11 405 patients (5.6%) in the SAVR group (P < 0.001). Among the patients who developed HDAVB, patients in the TAVI group were more likely to undergo permanent pacemaker implantation than those in the SAVR group (74.1% vs 64.7%; P < 0.001). The median interval from TAVI to pacemaker implantation was 2 days (interquartile range 1-3 days) vs 5 days (interquartile range 3-7 days) from SAVR to pacemaker implantation (P < 0.001). Among the patients who developed HDAVB, TAVI was associated with higher rates of permanent pacemaker implantation after adjusting for other comorbidities (odds ratio 1.41:95% confidence interval 1.13-1.77; P = 0.003). CONCLUSIONS: HDAVB occurred more commonly after TAVI compared to SAVR. HDAVB after TAVI compared to SAVR was associated with a higher rate of permanent pacemaker implantation at an earlier timing from the index procedure.

Cardiac pacing challenge in Sub-Saharan Africa environnement: experience of the Cardiology Department of Teaching Hospital Aristide Le Dantec in Dakar.

BACKGROUND: Cardiac pacing is a growing activity in Sub-Saharan Africa. There is little data on the characteristics of this interventional treatment in our regions. The goal was to evaluate the results of cardiac pacing in a referral service in sub-Saharan Africa. METHODS: We carried out a twelve-year retrospective study (from January 1st, 2004 to December 31st, 2015) in the Cardiology Department of Aristide Le Dantec University Hospital. This work included all patients who received definitive cardiac pacing during the study period and followed up in the service. RESULTS: In total we included 606 patients. There was a growing trend in activity with a peak in 2015 (17%). The average age was 70.6 ± 12.03 years. Some patients (15.4%) came from the subregion. The patients were mostly of medium socio-economic level (53%); 14% were of low socio-economic level. Patients were symptomatic in 85% of cases (37.4% syncope). The indications were dominated by complete atrioventricular block (81.5%); sinus dysfunction accounted for 1.9% of them. A temporary pacemaker was used in 60% of cases for an average duration of 5.1 ± 6.3 days. Antibiotics, local anesthesia and analgesics were used in all cases. Implanted pacemakers were single chamber in 56% of cases and double chamber in 44% of cases. In 39 patients (6.4%), the pacemaker was a « re-used ¼ one. The atrial leads were most often placed in a lateral position (94.5%). The ventricular ones were predominantly tined (95.7%) and more often located at the apical level. Complications were noted in 24 patients (3.9%), dominated by devices externalizations and infections, which together accounted for 2.7% of cases. The number of people in the cathlab was significantly higher and the duration of the temporary pacemaker was longer for patients who had a complication. There was no significant difference depending on the type of pacemaker used (new or reused). Seven (7) in hospital death cases were reported. CONCLUSION: Cardiac pacing is a growing activity in Dakar.

Health-related quality of life impact of a transcatheter pacing system.

BACKGROUND: Transcatheter pacing systems (TPS) provide a novel, minimally invasive approach in which a miniaturized, leadless pacemaker (PM) is transfemorally implanted in the right ventricle. We evaluated the health-related quality of life (HRQoL) impact, patient satisfaction, and activity restrictions following TPS in a large prospective multicenter clinical trial. METHODS AND RESULTS: Patients who underwent a Micra TPS implantation between December 2013 and May 2015 were included. HRQoL impact was evaluated using the Short-Form-36 (SF-36) questionnaire at baseline, 3, and 12 months. Patient satisfaction was assessed using a three-item questionnaire determining recovery, activity level, and esthetic appearance at 3 months. Implanting physicians compared the patient activity restrictions for TPS to traditional PM therapy. A total of 720 patients were implanted with a TPS (76 ± 11 years; 59% male). Of these patients, 702 (98%), 681 (95%), and 635 (88%) completed the SF-36 at baseline, 3 and 12 months, respectively. Improvements were observed at 3 and 12 months in all SF-36 domains and all attained statistical significance. Of 693 patients who completed the patient satisfaction questionnaire, 96%, 91%, 74% were (very) satisfied with their esthetic appearance, recovery, and level of activity, respectively. TPS discharge instructions were rated less restrictive in 49%, equally restrictive in 47%, and more restrictive in 4% of cases compared with traditional PM systems. CONCLUSIONS: TPS resulted in postimplant HRQoL improvements at 3 and 12 months, and high levels of patient satisfaction at 3 months. Further, TPS was associated with less activity restrictions compared with traditional PM systems.

Causes and predictors of 30-day readmission after cardiovascular implantable electronic devices implantation: Insights from Nationwide Readmissions Database.

INTRODUCTION: Readmissions are a burden on health care resources and have negative impact on patients. Cardiovascular implantable electronic devices (CIEDs) are frequently used in the management of rhythm disorders and advanced heart failure. We assessed 30-day readmissions in patients admitted for CIED implantation in a sample of United States patients. METHODS: Data were extracted from Nationwide Readmissions Database for calendar year 2013. Patients admitted for CIED implantation were identified using ICD-9 codes. Patients <18 years of age, with missing data, who died during hospitalization or discharged in December were excluded. Primary endpoint was all-cause 30-day readmission rate. Factors associated with 30-day readmissions were identified and examined using multivariate logistic regression. RESULTS: We identified 320,783 admissions for CIED implantations. After applying exclusion criteria, 290,420 patients were included in final analysis, out of whom 45,467 (15.7%) patients were readmitted within 30 days. Readmitted patients were younger and had more comorbidities. Septicemia (5.1%), pneumonia (3.4%), CHF (2.35%), and paroxysmal ventricular tachycardia (2.3%) were common primary causes of 30-day readmission. Young age, female gender, key comorbidities, weekend admissions, and admission to medium and large size hospital were independent predictors of 30-day readmissions. CONCLUSION: In our study, 15.7% patients were readmitted within 30 days of an index admission for CIED implantation. Most readmissions were due to infectious or cardiovascular causes. There is a need to identify patients at risk for readmission to improve outcomes and curb the cost of care.

Cardiac optogenetics: the next frontier.

The emerging technology of optogenetics uses optical and genetic means to monitor and modulate the electrophysiological properties of excitable tissues. While transforming the field of neuroscience, the technology has recently gained popularity also in the cardiac arena. Here, we describe the basic principles of optogenetics, the available and evolving optogenetic tools, and the unique potential of this technology for basic and translational cardiac electrophysiology. Specifically, we discuss the ability to control (augment or suppress) the cardiac tissue's excitable properties using optogenetic actuators (microbial opsins), which are light-gated ion channels and pumps that can cause light-triggered membrane depolarization or hyperpolarization. We then focus on the potential clinical implications of this technology for the treatment of cardiac arrhythmias by describing recent efforts for developing optogenetic-based cardiac pacing, resynchronization, and defibrillation experimental strategies. Finally, the significant obstacles and challenges that need to be overcome before any future clinical translation can be expected are discussed.

Five year trends (2008-2012) in cardiac implantable electrical device utilization in five European nations: a case study in cross-country comparisons using administrative databases.

Aims: Common methodologies for analysis of analogous data sets are needed for international comparisons of treatment and outcomes. This study tests using administrative hospital discharge (HD) databases in five European countries to investigate variation/trends in pacemaker (PM) and implantable cardioverter defibrillator (ICD) implant rates in terms of patient characteristics/management, device subtype, and initial implantation vs. replacement, and compares findings with existing literature and European Heart Rhythm Association (EHRA) reports. Methods and results: HD databases from 2008 to 2012 in Austria, England, Germany, Italy and Slovenia were interrogated to extract admissions (without patient identification) associated with PM and ICD implants and replacements, using direct cross-referencing of procedure codes and common methodology to compare aggregate data. 1 338 199 records revealed 212 952 PM and 62 567 ICD procedures/year on average for a 204.4 million combined population, a crude implant rate of about 104/100 000 inhabitants for PMs and 30.6 for ICDs. The first implant/replacement rate ratios were 81/24 (PMs) and 25/7 (ICDs). Rates have increased, with cardiac resynchronization therapy (CRT) subtypes for both devices rising dramatically. Significant between- and within-country variation persists in lengths of stay and rates (Germany highest, Slovenia lowest). Adjusting for age lessened differences for PM rates, scarcely affected ICDs. Male/female ratios remained stable at 56/44% (PMs) and 79/21% (ICDs). About 90% of patients were discharged to home; 85-100% were inpatient admissions. Conclusion: To aid in policymaking and track outcomes, HD administrative data provides a reliable, relatively cheap, methodology for tracking implant rates for PMs and ICDs across countries, as comparisons to EHRA data and the literature indicated.

Use of leadless pacemakers in Europe: results of the European Heart Rhythm Association survey.

The purpose of this European Heart Rhythm Association (EHRA) survey is to provide an overview of the current use of leadless pacemakers (LLPM) across a broad range of European centres. An online questionnaire was sent to centres participating in the EHRA Electrophysiology Research Network. Questions dealt with standards of care and policies used for patient management, indications, and techniques of implantation of LLPM. In total, 52 centres participated in the survey. Most (86%) reported using LLPM, although 82% of these centres implanted <30 LLPM devices during the last 12 months. Non-availability (36%), lack of reimbursement (55%), and cost of the device (91%) were factors limiting the use of LLPM. The most commonly reported indications for LLPM were permanent atrial fibrillation (83%), a history of complicated conventional pacemaker (87%), or an anticipated difficult vascular access (91%). Implantation of LLPM is perceived as an easy-to-do and safe procedure by most implanters (64%), while difficult or risky in 28%, and comparable to conventional pacemakers by only a few (8%). Local vascular complications were the most frequently reported major problems (28%), but a significant number of respondents (36%) have never encountered any issue after LLPM implantation. Although cost and reimbursement issues strongly influence the use of LLPM, most respondents (72%) anticipate a significant increase in device utilization within next 2 years.

The Hemodynamic Effects of Different Pacing Modalities After Cardiopulmonary Bypass in Patients With Reduced Left Ventricular Function.

OBJECTIVES: Patients with decreased left ventricular function undergoing cardiac surgery have a greater chance of difficult weaning from cardiopulmonary bypass and a poorer clinical outcome. Directly after weaning, interventricular dyssynchrony, paradoxical septal motion, and even temporary bundle-branch block might be observed. In this study, the authors measured arterial dP/dtmax, mean arterial pressure (MAP), and cardiac index using transpulmonary thermodilution, pulse contour analysis, and femoral artery catheter and compared the effects between right ventricular (A-RV) and biventricular (A-BiV) pacing on these parameters. DESIGN: Prospective study. SETTING: Single-center study. PARTICIPANTS: The study comprised 17 patients with a normal or prolonged QRS duration and a left ventricular ejection fraction ≤35% who underwent coronary artery bypass grafting with or without valve replacement. INTERVENTIONS: Temporary pacing wires were placed on the right atrium and both ventricles. Different pacing modalities were used in a standardized order. MEASUREMENTS AND MAIN RESULTS: A-BiV pacing compared with A-RV pacing demonstrated higher arterial dP/dtmax values (846 ± 646 mmHg/s v 800 ± 587 mmHg/s, p = 0.023) and higher MAP values (77 ± 19 mmHg v 71 ± 18 mmHg, p = 0.036). CONCLUSION: In patients with preoperative decreased left ventricular function undergoing coronary artery bypass grafting, A-BiV pacing improve the arterial dP/dtmax and MAP in patients with both normal and prolonged QRS duration compared with standard A-RV pacing. In addition, arterial dP/dtmax and MAP can be used to evaluate the effect of intraoperative pacing. In contrast to previous studies using more invasive techniques, transpulmonary thermodilution is easy to apply in the perioperative clinical setting.

Right ventricular pacemaker lead position is associated with differences in long-term outcomes and complications.

INTRODUCTION: Cardiac pacing from the right ventricular apex is associated with detrimental long-term effects and nonapical pacing locations may be associated with improved outcomes. There is little data regarding complications with nonapical lead positions. The aim of this study was to assess long-term outcomes and lead-related complications associated with differing ventricular lead tip position. METHODS AND RESULTS: All adult patients who underwent dual-chamber pacemaker implantation from 2004 to 2014 were included if they had postprocedure chest radiographs amenable to lead position determination. Long-term outcomes and lead-related complication rates were recorded. These were compared at 5 years between: (1) apical and septal leads, (2) apical and nonseptal nonapical (NSNA), and (3) apical and septal with >40% ventricular pacing. We retrospectively evaluated 3,450 patients, which included 238 with a septal position and 733 with NSNA lead positions. Septal lead position was associated with a lower mortality compared to apical leads (24% vs. 31%, P = 0.02). In patients with greater than 40% pacing, septal leads were associated with significantly higher rates of incident atrial fibrillation compared to apical leads (49% vs. 34%, P = 0.04). NSNA positions were associated with a significantly higher rate of lead dislodgement (4% vs. 2%, P = 0.005) and need for revision (8% vs. 5%, P = 0.005). CONCLUSIONS: Septal pacemaker lead position is associated with a lower mortality compared to apically placed leads, but a higher incidence of atrial fibrillation with higher percentage ventricular pacing. NSNA lead locations are associated with more complications and should be avoided.

Access to and clinical use of cardiac implantable electronic devices and interventional electrophysiological procedures in the European Society of Cardiology Countries: 2016 Report from the European Heart Rhythm Association.

AIMS: The aim of this analysis was to provide comprehensive information on the access to and use of cardiac implantable electronic device (CIED) and catheter ablation therapy in the European Society of Cardiology (ESC) area. METHODS AND RESULTS: The European Heart Rhythm Association (EHRA) has been collecting descriptive and quantitative data on invasive arrhythmia therapies since 2008. This year 50 of the 56 ESC member countries provided data for the EHRA White Book. Up-to-date information on procedure rates for the last 5 years together with information on demographics, economy, vital statistics, local healthcare systems, and training activities is presented for each country and the 5 geographical ESC regions. Our analysis indicated that considerable heterogeneity in the access to arrhythmia therapies still exists across the ESC area. In 2015, the CIED implantation rates per million population were highest in the Western followed by the Southern and Northern European countries. The catheter ablation activity was largest in the Western followed by the Northern and Southern areas. Overall, the procedure rates were 3-10 times higher in the European than in the non-European ESC countries. Economic resources were not the only driver for utilization of arrhythmia therapies as in some Eastern European countries with relative low gross domestic product the procedure rates exceeded the average values. CONCLUSION: These data will help the healthcare professionals and stakeholders to identify and to understand in more depth the trends, disparities, and gaps in cardiac arrhythmia care and thereby promote harmonization of cardiac arrhythmias therapies in the ESC area.

The Complexity of the His Bundle: Understanding Its Anatomy and Physiology through the Lens of the Past and the Present.

In this paper, we describe the anatomy and physiology of the His bundle and describe the mechanisms by which permanent His-bundle pacing can be accomplished.

[Cardiac contractility modulation. A new form of therapy for patients with heart failure and narrow QRS complex?]. / Kardiale Kontraktilitätsmodulation. Eine neue Therapieform für herzinsuffiziente Patienten mit schmalem Kammerkomplex?

Cardiac contractility modulation (CCM) is a stimulation therapy by an implantable impulse generator, which enhances ventricular contractile performance by delivering CCM impulses to the right ventricle during the absolute refractory period. The CCM signals mediate increased inotropy by prolonging the duration of the action potential, which leads to an enhanced influx of calcium into cardiomyocytes and a greater release of calcium by the sarcoplasmic reticulum. The increase of cardiac contractility is not associated with increased oxygen consumption. Several small studies have shown that CCM therapy can safely improve symptoms of heart failure and peak oxygen consumption in patients with moderate to severe heart failure who are not eligible for resynchronization therapy. Therefore, CCM is a novel potential therapy for patients with heart failure, an ejection fraction ≤ 35 % and a normal QRS duration < 130 ms. However, apart from selecting appropriate patients for CCM therapy there are still unanswered questions, such as the impact of CCM therapy on established clinical endpoints. At present no data are available which have shown that CCM therapy leads to reduction of hospitalization for heart failure or mortality.

Effect of induced LV dyssynchrony by right ventricular apical pacing on all-cause mortality and heart failure hospitalization rates at long-term follow-up.

BACKGROUND: Right ventricular apical (RVA) pacing may induce left ventricular (LV) dyssynchrony. The long-term prognostic implications of induction of LV dyssynchrony were retrospectively evaluated in a cohort of patients who underwent RVA pacing. METHODS: A total of 169 patients (62 ± 13 years, 69% male) with high RVA pacing burden were included. Echocardiographic evaluation of LV volumes, ejection fraction, and dyssynchrony were performed before and after device implantation. LV dyssynchrony was assessed by 2-dimensional radial strain speckle tracking echocardiography. Based on the median LV dyssynchrony value after RVA pacing, the patient population was dichotomized (induced and noninduced LV dyssynchrony groups) and was followed up for the occurrence of all-cause mortality and heart failure (HF) hospitalization. RESULTS: Baseline mean LV ejection fraction was 51 ± 11%. Median LV dyssynchrony value was 40 ms (12-85 ms) before RVA pacing and increased to 91 ms (81-138 ms) after a median of 13 months (3-26 months) after RVA pacing. Median follow-up duration was 70 months (interquartile range 42-96 months). Patients with induced LV dyssynchrony, defined as LV dyssynchrony value superior to the median at follow-up (≥91 ms), showed higher mortality rates (5% and 27% vs. 1% and 3% at 3 and 5 years follow-up; log-rank P = 0.003) and HF hospitalization rates (18% and 24% vs. 3% and 4% at 3 and 5 years follow-up; log-rank P < 0.001) than patients with LV dyssynchrony <91 ms after RVA pacing. A multivariate model was developed to identify independent associates of a combined endpoint of all-cause mortality or HF hospitalization. Induction of LV dyssynchrony was independently associated with increased risk of combined endpoint (HR [95% CI]: 3.369 [1.732-6.553], P < 0.001). CONCLUSION: Induction of LV dyssynchrony by RVA pacing is associated with worse long-term mortality and increased HF hospitalization rates.

Standards for device implantation and follow-up: personnel, equipment, and facilities: results of the European Heart Rhythm Association Survey.

Cardiac device implantation is the most common of all invasive cardiac electrophysiological procedures. Over 250 000 devices are implanted each year in Europe. The purpose of this European Heart Rhythm Association (EHRA) survey was to assess the facilities, personnel, and protocols of members of the EHRA electrophysiology (EP) research network involved in device implantation. There were 68 responses to the questionnaire. The survey responses were mainly (84%) from medium- to high-volume device implanting centres, performing >200 implants per year, with over 50% performing >400 implants per year. Most consultants are male (85%), half of all centres had no female consultants, and only one in six had more than one female consultant. There is trend towards specialization in device implantation. The combination of device implantation and EP is still common (76% of all centres) but only 34% of centres have consultants performing device implantation and coronary intervention. Moreover, 23% of centres have all device implantation performed by consultants who do not perform any other types of procedure. Cardiac device implantation as a day case is the planned admission for routine elective device implantation in 30% of hospitals, 47% of hospitals have a single night stay, and 23% of hospitals have admission durations of two or more nights. Device implantation is available as a 24 h service, 365 days a year in 38% of hospitals. The commonest other model was as a daytime service on weekdays in 45% of hospitals.

Permanent pacemaker insertion after CoreValve transcatheter aortic valve implantation: incidence and contributing factors (the UK CoreValve Collaborative).

BACKGROUND: Permanent pacemaker (PPM) requirement is a recognized complication of transcatheter aortic valve implantation. We assessed the UK incidence of permanent pacing within 30 days of CoreValve implantation and formulated an anatomic and electrophysiological model. METHODS AND RESULTS: Data from 270 patients at 10 centers in the United Kingdom were examined. Twenty-five patients (8%) had preexisting PPMs; 2 patients had incomplete data. The remaining 243 were 81.3±6.7 years of age; 50.6% were male. QRS duration increased from 105±23 to 135±29 milliseconds (P<0.01). Left bundle-branch block incidence was 13% at baseline and 61% after the procedure (P<0.001). Eighty-one patients (33.3%) required a PPM within 30 days. Rates of pacing according to preexisting ECG abnormalities were as follows: right bundle-branch block, 65.2%; left bundle-branch block, 43.75%; normal QRS, 27.6%. Among patients who required PPM implantation, the median time to insertion was 4.0 days (interquartile range, 2.0 to 7.75 days). Multivariable analysis revealed that periprocedural atrioventricular block (odds ratio, 6.29; 95% confidence interval, 3.55 to 11.15), balloon predilatation (odds ratio, 2.68; 95% confidence interval, 2.00 to 3.47), use of the larger (29 mm) CoreValve prosthesis (odds ratio, 2.50; 95% confidence interval, 1.22 to 5.11), interventricular septum diameter (odds ratio, 1.18; 95% confidence interval, 1.10 to 3.06), and prolonged QRS duration (odds ratio, 3.45; 95% confidence interval, 1.61 to 7.40) were independently associated with the need for PPM. CONCLUSION: One third of patients undergoing a CoreValve transcatheter aortic valve implantation procedure require a PPM within 30 days. Periprocedural atrioventricular block, balloon predilatation, use of the larger CoreValve prosthesis, increased interventricular septum diameter and prolonged QRS duration were associated with the need for PPM.