bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence and Characterization of Asymptomatic Pacemaker and ICD Lead Perforation on CT
Authors: HIRSCHL DAVID A. , JAIN VINEET R. , SPINDOLA‐FRANCO HUGO , GROSS JAY N. , HARAMATI LINDA B. 
Published: January 2007

Background: Pacemakers and implantable cardiac defibrillators (ICDs) are widely used for the management of cardiac arrhythmias and congestive heart failure (CHF). Acute implantation complication rates range from 3% to 7%. The aim of this study is to describe the incidence of lead perforation on computed tomography (CT), and correlate these findings with electrophysiologic data.
Methods: Images of 100 consecutive patients with permanent pacemakers (n = 72) or ICDs (n = 28) who underwent multidetector CTs of the chest were identified. Cases were reviewed by 2 cardiothoracic radiologists, and a third if there was disagreement. Each CT was reviewed for device and fixation type, tip position, and presence of pericardial effusion. Results were correlated with lead impedance and pacing threshold, when available [79% (79/100)]. A cardiac electrophysiologist interpreted device data.
Results: All 100 patients had right ventricular leads (58 passive, 42 active) and 61 had right atrial leads (12 passive, 49 active). 15% (15/100) of patients had a lead perforation. Perforation rates were 15% (9/61) for atrial and 6% (6/100) for ventricular leads (P < 0.05, chi square). Four of 28 (14%) right ventricular ICD leads and 2 of 72 (3%)
right ventricular pacemaker leads were perforated (P < 0.05, chi square). 12% (6/49) of active right atrial leads, and 25% (3/12) of passive right atrial leads perforated (P = NS, chi square). 7% (3/42) of active right ventricular leads, and 5% (3/58) of passive ventricular leads perforated (P = NS, chi square). Electrophysiologic parameters did not differ significantly between perforated and nonperforated leads.
Conclusion: Asymptomatic perforation is a common phenomenon and rarely resulting in electrophysiologic consequences. Atrial leads perforated more frequently than ventricular leads, and ventricular ICD leads perforated more frequently than ventricular pacemaker leads.
Economic Analysis of a Randomized Trial of Biventricular Pacing in Canada
Authors: BENTKOVER JUDITH D. , DORIAN PAUL , THIBAULT BERNARD , GARDNER MARTIN 
Published: January 2007

Background: Congestive heart failure (CHF) has been shown to affect 5% of the Canadian adult population, and leads to 9.5 deaths per 100 cardiac‐related hospitalizations in Canada. The economic outcomes from biventricular pacing for heart failure are not well understood. This study analyzes resource utilization and related costs associated with CHF for patients who receive standard implantable cardiac defibrillators (ICDs) versus those who receive ICD plus biventricular pacing or cardiac resynchronization therapy (CRT).
Methods: The Canadian analysis of resynchronization therapy in heart failure (CART‐HF) study included 72 patients with New York Heart Association class II‐IV CHF requiring an ICD. Patients were randomized to receive either ICD + CRT treatment or ICD treatment alone. Medical resource utilization data were collected for 6 months following treatment and were applied to representative costs for the provinces of Quebec and Ontario. Resource utilization was subcategorized into pharmacological therapy, physician visits, hospitalizations, adverse events, and productivity losses.
Results: Post‐treatment, per patient costs for the CRT + ICD treatment group were less than the follow‐up costs for patients receiving ICD treatment only in each province. Mean savings for patients receiving biventricular therapy were CAD$2,420 in Quebec and CAD$2,085 in Ontario during the 6‐month follow‐up.
Conclusions: These analyses indicate that savings in post‐implant health‐care utilization (hospitalizations and pharmacological therapy) can offset some of the device and procedural costs associated with CRT devices.
Implantation of Active Fixation Leads in Coronary Veins for Left Ventricular Stimulation: Report of Five Cases
Authors: HANSKY BERT , VOGT JUERGEN , GUELDNER HOLGER , SCHULTE‐EISTRUP SEBASTIAN , LAMP BARBARA , HEINTZE JOHANNES , HORSTKOTTE DIETER , KOERFER REINER 
Published: January 2007

Background: Securing transvenous left ventricular (LV) pacing leads without an active fixation mechanism in proximal coronary vein (CV) segments is usually challenging and frequently impossible. We investigated how active fixation leads can be safely implanted in this location, how to avoid perforating the free wall of the CV, and how to recognize and respond to perforations.
Materials and Methods: In five patients with no alternative to LV pacing from proximal CV segments, 4 Fr SelectSecure (Medtronic, Minneapolis, MN, USA) leads, which have a fixed helix, were implanted through a modified 6 Fr guide catheter with a pre‐shaped tip (Launcher, Medtronic).
Results: Active fixation leads were successfully implanted in proximal CVs in five patients. There were no complications. Acute and chronic pacing thresholds were comparable to those of conventional CV leads. The pre‐shaped guide catheter tip remains in close proximity to the myocardial aspect of the CV, directing the lead helix toward a safe implantation site.
Conclusions: If only proximal CV pacing sites are available, 4 Fr SelectSecure leads can be safely implanted through a modified Launcher guide catheter, avoiding more invasive implantation techniques. Other than venous stenting or implantation of leads with retractable tines, SelectSecure leads are expected to remain extractable.
Cardiac Resynchronization Therapy Optimization by Ultrasonic Cardiac Output Monitoring (USCOM) Device
Authors: SIU CHUNG‐WAH , TSE HUNG‐FAT , LEE KATHY , CHAN HON‐WAH , CHEN WAI‐HONG , YUNG CINDY , LEE STEPHEN , LAU CHU‐PAK 
Published: January 2007

Objectives: We investigated the accuracy and feasibility of a 2D echo‐independent ultrasonic continuous wave Doppler cardiac output monitoring device (USCOM) operated by trained nurse for the atrio‐ventricular interval (AVI) optimization in cardiac resynchronization therapy (CRT).
Background: CRT is of proven benefit in patients with advanced chronic heart failure and ventricular conduction delay. Appropriate AVI selection is critical to optimize hemodynamic in CRT. Currently, most non‐invasive methods for AVI optimization are often complicated and labor‐intensive.
Methods: USCOM method, Ritter method, and aortic outflow cardiac output method were used to determine the optima AVI in 20 patients with CRT. The accuracy and time for measurement of each method were determined.
Results: The optimal AVI determined by USCOM method had good correlation with Ritter's method and aortic outflow estimated cardiac output method (r2= 0.78, P < 0.01 and r2= 0.73, P < 0.01, respectively). The optimal AVI determined USCOM method showed good agreement (within 10 msec range) with Ritter's method (85% patients) and aortic outflow estimated cardiac output method (80%). The mean time for determining AVI using USCOM method was shorter than that with aortic outflow method (7.1 ± 0.7 min vs 12.7 ± 1.1 min, P < 0.01), whereas the mean time was shortest for Ritter method (4.7 ± 1.6 min vs 7.1 ± 0.7 min, P < 0.01).
Conclusion: USCOM device operated by trained nurse can provide a simple, accurate, and fast non‐invasive method for the AVI optimization in CRT population.
Activation Sequence Modification During Cardiac Resynchronization by Manipulation of Left Ventricular Epicardial Pacing Stimulus Strength
Authors: TEDROW USHA B. , STEVENSON WILLIAM G. , WOOD MARK A. , SHEPARD RICHARD K. , HALL KIM , PELLEGRINI CHRISTINE P. , ELLENBOGEN KENNETH A. 
Published: January 2007

Background: Success of cardiac resynchronization therapy (CRT) depends on altering electrical ventricular activation (VA) to achieve mechanical benefit. That increases in stimulus strength (SS) can affect VA has been demonstrated previously in cardiomyopathy patients undergoing ablation.
Objective: To determine whether increasing SS can alter VA during CRT.
Methods: In 71 patients with CRT devices, left ventricle (LV) pacing was performed at escalating SS. Timing from pacing stimulus to right ventricular (RV) electrogram, ECG morphology, and maximal QRS duration on 12 lead ECG were recorded.
Results: Demographics: Baseline QRS duration 153 ± 25 ms, ischemic cardiomyopathy 48%, ejection fraction 24%± 7%. With increased SS, conduction time from LV to right ventricle (RV) decreased from 125 ± 56 ms to 111 ± 59 ms (P = 0.006). QRS duration decreased from 212 ± 46 ms to 194 ± 42 ms (P = 0.0002). A marked change in QRS morphology occurred in 11/71 patients (15%). The RV ring was the anode in 6, while the RV coil was the anode in 5. Sites with change in QRS morphology showed decrease in conduction time from LV to RV from 110 ± 60 ms to 64 ± 68 ms (P = 0.04). Twelve patients (16%) had diaphragmatic stimulation with increased SS.
Conclusions: Increasing LV SS reduces QRS duration and conduction time from LV to RV. Recognition of significant QRS morphology change is likely clinically important during LV threshold programming to avoid unintended VA change.
Changes in Heart Rate Variability, Quality of Life, and Activity in Cardiac Resynchronization Therapy Patients: Results of the HF‐HRV Registry
Authors: GILLIAM F. ROOSEVELT , KAPLAN ANDREW J. , BLACK JAMES , CHASE KELLIE J. , MULLIN CHRISTOPHER M. 
Published: January 2007

Background: Cardiac resynchronization therapy (CRT) is a viable therapy in the treatment of heart failure (HF). Heart rate variability (HRV) is a prognostic marker of HF and mortality and is a sign of autonomic dysfunction. Acute improvements in measures of HRV have been demonstrated after CRT in small clinical studies. The purpose of the present study was to evaluate changes in HRV and patient outcomes over time and the relationship between these changes in a large generalized sample of patients who received CRT with defibrillator (CRT‐D).
Methods: The Heart Failure‐Heart Rate Variability (HF‐HRV) registry enrolled 1,421 patients who received a CRT‐D device capable of measuring HRV. Patients were followed for a 1‐year period. Device diagnostics, including HRV footprint; standard deviation of averaged normal R to R intervals (SDANN); and mean, minimum, and maximum heart rate were measured at each visit, in addition to activity log, New York Heart Association (NYHA) class, and quality of life (QOL) data.
Results: This large sample of HF patients showed an overall improvement in SDANN (69.2 ± 25.5, 78.5 ± 27.8, 79.4 ± 27.2, 80.7 ± 28.2) and HRV footprint (31.5 ± 11.8, 33.4 ± 12.3, 34.2 ± 12.2, 34.5 ± 12.3) at the 2 week, 3 month, 6 month, and 12 month visits, respectively (both P < 0.001). There were also significant changes over time in clinical status (improved QOL, increased activity, and improved NYHA, all P < 0.0001), with the greatest changes occurring between the 2 week and 3 month visits.
Conclusion: In conclusion, these study results demonstrate that device measured HRV parameters and patient outcomes significantly improve after receipt of CRT.
Remote, Wireless, Ambulatory Monitoring of Implantable Pacemakers, Cardioverter Defibrillators, and Cardiac Resynchronization Therapy Systems: Analysis of a Worldwide Database
Authors: LAZARUS ARNAUD 
Published: January 2007

Study Objective: To describe the daily routine application of a new telemonitoring system in a large population of cardiac device recipients.
Methods: Data transmitted daily and automatically by a remote, wireless Home Monitoring™ system (HM) were analyzed. The average time gained in the detection of events using HM versus standard practice and the impact of HM on physician workload were examined. The mean interval between device interrogations was used to compare the rates of follow‐up visits versus that recommended in guidelines.
Results: 3,004,763 transmissions were made by 11,624 recipients of pacemakers (n = 4,631), defibrillators (ICD; n = 6,548), and combined ICD + cardiac resynchronization therapy (CRT‐D) systems (n = 445) worldwide. The duration of monitoring/patient ranged from 1 to 49 months, representing 10,057 years. The vast majority (86%) of events were disease‐related. The mean interval between last follow‐up and occurrence of events notified by HM was 26 days, representing a putative temporal gain of 154 and 64 days in patients usually followed at 6‐ and 3‐month intervals, respectively. The mean numbers of events per patient per month reported to the caregivers for the overall population was 0.6. On average, 47.6% of the patients were event‐free. The mean interval between follow‐up visits in patients with pacemakers, single‐chamber ICDs, dual chamber ICDs, and CRT‐D systems were 5.9 ± 2.1, 3.6 ± 3.3, 3.3 ± 3.5, and 1.9 ± 2.9 months, respectively.
Conclusions: This broad clinical application of a new monitoring system strongly supports its capability to improve the care of cardiac device recipients, enhance their safety, and optimize the allocation of health resources.
Upgrading from Single Chamber Right Ventricular to Biventricular Pacing in Permanently Paced Patients with Worsening Heart Failure: The RD‐CHF Study
Authors: LECLERCQ CHRISTOPHE , CAZEAU SERGE , LELLOUCHE DAVID , FOSSATI FABIEN , ANSELME FRÉDERIC , DAVY JEAN‐MARC , SADOUL NICOLAS , KLUG DIDIER , MOLLO LUCA , DAUBERT JEAN‐CLAUDE 
Published: January 2007

Background: Biventricular (BiV) stimulation lowers morbidity and mortality in patients with drug‐refractory congestive heart failure (CHF), depressed left ventricular (LV) function, and ventricular dyssynchrony in absence of indication for permanent cardiac pacing. This pilot, single‐blind, randomized, cross‐over study examined the safety and efficacy of upgrading conventional pacing systems to BiV stimulation in patients with advanced CHF.
Methods: We included 56 patients in New York Heart Association (NYHA) functional classes III or IV despite optimal drug treatment and ventricular dyssynchrony (interventriclar delay >40 ms or LV preejection delay >140 ms) in need of pacemaker replacement. We compared the patients' functional status, arrhythmias, and standard echocardiographic measurements during 3 months of conventional, single right ventricular (RV) versus 3 months of BiV stimulation.
Results: There were 44 patients in the cross‐over phase. QRS duration was shortened by 23% and LV preejection delay by 16% with BiV stimulation. NYHA functional class, 6‐minute hall walk and quality of life score were significantly improved with BiV stimulation compared with single RV pacing by 18%, 29%, and 19%, respectively. No significant difference was observed in the ventricular arrhythmia burden or LV reverse remodeling between the 2 periods.
Conclusions: This pilot study showed that upgrading from RV pacing to BiV pacing significantly improves symptoms and exercise tolerance in chronically paced patients with advanced CHF and mechanical dyssynchrony.
Long‐Term Follow‐Up of Biventricular Pacing Using a Totally Endocardial Approach in Patients with End‐Stage Cardiac Failure
Authors: PASQUIÉ J.L. , MASSIN F. , MACIA J.C. , GERVASONI R. , BORTONE A. , CAYLA G. , GROLLEAU R. , LECLERCQ F. 
Published: January 2007

Background: Besides standard left ventricular (LV) stimulation via the coronary sinus, a transseptal approach allows left ventricular endocardial stimulation. We report our long‐term observations with biventricular stimulation, using a strictly endocardial system for patients presenting with severe congestive heart failure.
Methods: Six patients with nonischemic cardiomyopathy (mean age = 60 ± 9.6 years, women) in New York Heart Association (NYHA) functional class III (n = 5) or IV, despite optimal drug therapy, and a mean LV ejection fraction of 24 ± 3%, underwent implantation of biventricular stimulation systems between April 1998 and March 1999. All presented with left bundle branch block and an increased LV end‐diastolic diameter (mean = 66 ± 5 mm). In all patients, a bipolar pacing lead was implanted in the lateral LV wall using a direct transseptal approach. After implantation, all patients received oral anticoagulation.
Results: QRS duration decreased from 184 ± 22 ms to 108 ± 11 ms. NYHA functional class decreased to II in all patients within 1 month. Over a 85 ± 5 month follow‐up, two patients underwent cardiac transplantation, 2 and 4 years after device implantation, respectively; two patients died of end‐stage heart failure 4 years after system implantation; and two patients were alive in functional class II. One patient, who experienced syncope due to fast ventricular, underwent implantation of an ICD. One transient ischemic attack occurred in a patient whose anticoagulation was temporarily interrupted.
Conclusions: Long‐term endocardial biventricular stimulation via a transseptal approach was safe and effective in this small population. This approach needs to be further compared with conventional epicardial pacing via the coronary sinus
Three Years of Cardiac Resynchronization Therapy: Could Superior Benefits be Obtained in Patients with Heart Failure and Narrow QRS?
Authors: GASPARINI MAURIZIO , REGOLI FRANÇOIS , GALIMBERTI PAOLA , CERIOTTI CARLO , BONADIES MARIKA , MANGIAVACCHI MAURIZIO , ANDREUZZI BRUNO , BRAGATO RENATO , PINI DANIELA , KLERSY CATHERINE , GRONDA EDOARDO 
Published: January 2007

Aim of the study: To examine the long‐term effects of cardiac resynchronization therapy (CRT) in patients presenting with heart failure (HF) and QRS ≤120 ms.
Methods: This was a prospective, longitudinal study of 376 patients [mean age = 65 years, mean left ventricular (LV) ejection fraction (EF) = 29%, mean QRS duration =165 ms, mean distance covered during a 6‐minute hall walk (6‐MHW) = 325 m], who underwent successful implantation of CRT systems. The QRS duration at baseline was ≤120 ms in 45 patients (12%) who were not pre‐selected by echocardiographic criteria of dyssynchrony, and >120 ms in the remaining 331 patients. The baseline characteristics of the 2 groups were similar. We evaluated indices of cardiac function, percentage of responders, and survival rates over a mean 28‐month follow‐up.
Results: Both groups experienced similar long‐term increases in 6‐MHW, and decreases in New York Heart Association functional class and LV end‐systolic volume (all comparisons P < 0.0001 in both groups). Time interaction of changes in LVEF and percentage of responders were significantly different (P = 0.03 and P = 0.004, respectively), in favor of the narrow QRS group, where the changes were sustained and persisted at 2 and 3 years. The long‐term death rate from HF was lower in the group with narrow than in the group with wide QRS complex (P = 0.04; log‐rank test).
Conclusions: CRT confers considerable long‐term clinical, functional, and survival benefits in patients presenting with HF and narrow QRS, not preselected by echocardiographic criteria of dyssynchrony. Caution is advised before denying CRT to these patients on the basis of QRS width only.
Long‐Term Performance of Coronary Sinus Leads Used for Cardiac Resynchronization Therapy
Authors: IULIANO ASSUNTA , SHOPOVA GERGANA , DE SIMONE ANTONIO , SOLIMENE FRANCESCO , TURCO PIETRO , MARRAZZO NATALE , LA ROCCA VINCENZO , CIARDIELLO CARMINE , AGRUSTA MARCO , STABILE GIUSEPPE 
Published: January 2007

Background: Little is known regarding the long‐term performance of coronary sinus (CS) leads, which have an effect on the longevity of cardiac resynchronization therapy (CRT) systems.
Methods: This study included 109 patients (79 men) whose mean age was 68 ± 9 years, New York Heart Association (NYHA) functional class 3.2 ± 0.5, and left ventricular ejection fraction 25.6 ± 6.6%, and who underwent CRT (n = 45) or CRT‐D (n = 64) systems implants for management of idiopathic (53%), ischemic (40%), or miscellaneous (7%) dilated cardiomyopathy. Unipolar (n = 57) or bipolar (n = 52) leads were placed into the CS venous system.
Results: At implant, no significant difference was observed between unipolar and bipolar leads with respect to mean sensing performance (14 ± 6 mV vs 14 ± 8 mV, P = 0.97), pacing impedance (875 ± 234 ohms vs 943 ± 331 ohms, P = 0.24), and stimulation energy threshold (2 ± 3.2 μJ vs 1.13 ± 1.5 μJ, P = 0.08). At a median follow‐up of 33 months, a significant decrease in stimulation impedance and increase in stimulation energy threshold was observed with unipolar (689 ± 122 vs 875 ± 234 ohms, P < 0.01, and 8.34 ± 10.4 μJ vs 2 ± 3.2 μJ, P < 0.001, respectively) as well as with bipolar (735 ± 268 ohms vs 943 ± 331 ohms, P < 0.01, and 4.81 ± 9.92 vs 1.13 ± 1.5 μJ, P = 0.02, respectively) leads. No significant difference in sensing performance was observed with either type of lead (10 ± 5 mV vs 14 ± 6 mV and 10 ± 6 mV vs 14 ± 8 mV, respectively). At long‐term follow‐up, no significant difference among any sensing or stimulation parameter was observed between unipolar and bipolar leads.
Conclusions: At long‐term follow‐up, a significant increase in the energy required for stimulation was observed, whereas sensing performance remained unchanged. The increase in energy capture threshold was less marked with bipolar than with unipolar leads.
Segmental Wall Motion Abnormality Analyzed by Equilibrium Radionuclide Angiography and Improvement in Ventricular Function by Cardiac Resynchronization Therapy
Authors: EDER VERONIQUE , FAUCHIER LAURENT , COURTEHOUX MAXIME , BONNET PIERRE , BABUTY DOMINIQUE 
Published: January 2007

Introduction: The purpose of this study was to determine the impact of the left ventricular (LV) segmental wall motion abnormalities detected by equilibrium radionuclide angiography (ERNA) on the improvement in LV and right ventricular (RV) function during biventricular (BIV) stimulation.
Results: We studied 28 patients in NYHA functional classes III or IV and QRS duration >150 ms on resting electrocardiogram. ERNA was performed before and during BIV stimulation at a 6‐month follow‐up. A significant shortening of QRS duration was observed during BIV stimulation (165 ± 5 ms before vs 133 ± 6 ms during, P < 0.01). Wall motion abnormalities (WMA) were observed in 16 patients (10 with nonischemic cardiomyopathies). In this group, LV and RV ejection fractions (EF) did not increase during BIV stimulation (LVEF=22 ± 2% vs 20 ± 1.6%, ns; RVEF=34 ± 3% vs 37 ± 3.8%, ns). Significant increases in RVEF (23 ± 3.2%→38 ± 2.9%, P=0.001) and LVEF (20 ± 2.5%→30 ± 3%, P=0.01) were observed in the group of patients without segmental WMA and with global hypokinesia (GH). In this group, a significant decrease in the dispersion in the phase of RV contraction was observed (SD=39 ± 5 vs 26 ± 2 ms; P < 0.01). WMA predicted an increase in LVEF, in contrast to a baseline 6‐minute‐walk test, maximal oxygen consumption and LVEF, or amount of QRS shortening.
Conclusions: BIV stimulation increased in LV and RV EF in patients with ventricular dyssynchrony in absence of segmental WMA. ERNA was reliable in the selection of candidates for CRT.