Germana Panattoni

Clinical and procedural outcome of patients implanted with a quadripolar left ventricular lead: Early results of a prospective multicenter study

BACKGROUND Recent studies suggest that cardiac resynchronization therapy (CRT) with a quadripolar left ventricular (LV) lead results in low rates of dislocation and phrenic nerve stimulation (PNS) acutely and at short-term follow-up. Confirmation of these results by long-term observational studies is needed. OBJECTIVE To evaluate the long-term procedural and clinical outcomes of CRT patients implanted with a quadripolar LV lead. METHODS A total of 154 consecutive heart failure patients (79% men, age 68 ± 10 years) having CRT implantation attempts with a quadripolar LV lead were included in this observational registry. Demographic and clinical data were preoperatively collected, and patients were followed up for at least 6 months. RESULTS The overall implant success rate after coronary sinus cannulation was 97.4%. Mean overall duration and fluoroscopy time of successful procedures was 112 ± 22 and 16 ± 8 minutes, respectively, while 17 ± 13 minutes were necessary for the LV lead placement. After implant, the conventional bipolar configuration was used as the final pacing configuration in 33.3% of the patients. Four lead dislodgments (requiring reoperation) and 9 clinical PNS were reported during follow-up; reprogramming of the device was sufficient to prevent PNS in all patients. Once placed, the LV lead remained stable with excellent pacing thresholds during follow-up (15 ± 5 months). Overall, there were 71.3% CRT responders as assessed by 6-month echocardiography, and 66% improved at least 1 New York Heart Association class. CONCLUSION Over the longer term, CRT with the quadripolar LV lead is associated with excellent pacing thresholds, low rates of dislocations, and PNS.

Hospitalization rates and associated cost analysis of cardiac resynchronization therapy with an implantable defibrillator and quadripolar vs. bipolar left ventricular leads: a comparative effectiveness study.

Aims This study compares, from a prospective, observational, non-randomized registry, the post-implant hospitalization rates and associated healthcare resource utilization of cardiac resynchronization therapy-defibrillator (CRT-D) patients with quadripolar (QUAD) vs. bipolar (BIP) left ventricular (LV) leads. Methods and results Between January 2009 and December 2012, 193 consecutive patients receiving de novo CRT-D implants with either a QUAD (n = 116) or a BIP (n = 77) LV lead were enrolled at implant and followed until July 2013 at a single-centre, university hospital. Post-implant hospitalizations related to heart failure (HF) or LV lead surgical revision and associated payer costs were identified using ICD-9-CM diagnosis and procedure codes. Italian national reimbursement rates were determined. Propensity scores were estimated using a logistic regression model based upon 11 pre-implant baseline characteristics and were used to derive a 1 : 1 matched cohort of QUAD (n = 77) and BIP (n = 77) patients. Hospitalization rates for the two groups were compared using negative binomial regression and associated payer costs were compared using non-parametric bootstrapping (×10 000) and one-sided hypothesis test. Hospitalization rates of the QUAD group [0.15/ patient (pt)-year] were lower than those of the BIP group (0.32/ pt-year); the incidence rate ratio was 0.46, P = 0.04. The hospitalization costs for the QUAD group (434 ± 128 €/pt-year) were lower than those for the BIP group (1136 ± 362 €/pt-year). The average difference was 718 €/pt-year, P = 0.016. Conclusions In this comparative effectiveness assessment of well-matched groups of CRT-D patients with quadripolar and bipolar LV leads, QUAD patients experienced a lower rate of hospitalizations for HF and LV lead surgical revision, and a lower cost burden. This has important implications for LV pacing lead choice.

Impact of continuous intracardiac ST-segment monitoring on mid-term outcomes of ICD-implanted patients with coronary artery disease. Early results of a prospective comparison with conventional ICD outcomes

Background Although myocardial ischaemia monitored by some implantable cardioverter-defibrillators (ICDs) might improve patient care, the clinical usefulness of this technology has not yet been validated. Objective To investigate the potential impact of ICD-based ischaemia monitoring on clinical care and patient management of ICD recipients. Design Prospective, controlled, non-randomised study. Setting Single-centre, university hospital. Patients Consecutive patients with known coronary artery disease, followed up for at least 6 months. Interventions Patients implanted with either an ICD providing continuous intracardiac ST monitoring (n=53; ST group) or with an ICD without this capability (n=50). Main outcome measures Major cardiovascular events, appropriateness of ST-shift episodes and unscheduled device-related visits. Results During follow-up (15.4±8.4 months), one patient experienced ST-shift events confirmed by angiography to be related to myocardial ischaemia. Myocardial infarction was a rare event and occurred in one patient (ST group) who had an ST-elevation myocardial infarction 3 weeks after the implant, but at this time the algorithm had not yet been activated. In the ST group, seven patients had one or more episodes of false-positive ST events (median 9, range 1–90). The programmable features of the device helped overcome the problem in six patients. Among patients with a remote monitoring system, unscheduled outpatient visits were significantly increased in the ST group (17 vs 4; p=0.032). Conclusions Although, this study was underpowered by the small number of acute ischaemic events, ICD-based ST monitoring failed to provide a benefit over ICDs without this capability and increased unscheduled evaluations in patients with remote follow-up. The sensitivity and specificity of the algorithm still require validation.

Predictive value of fragmented QRS in primary prevention implantable cardioverter defibrillator recipients with left ventricular dysfunction.

Introduction In primary prevention implantable cardioverter defibrillator (ICD) patients, the incidence of appropriate ICD therapy is relatively low, prompting better risk stratification. Fragmented QRS (fQRS) on a 12-lead ECG has been associated with adverse outcomes. The aim of this study was to evaluate the prognostic value of fQRS in ICD recipients. Methods Consecutive ICD patients implanted at our institution for primary prevention of sudden cardiac death (SCD) were retrospectively evaluated. Patients were divided in two groups based on the presence or the absence of fQRS on the ECG obtained before ICD implantation. The endpoint of the study was all-cause mortality or the occurrence of any appropriate ICD-delivered therapy, whether shock or antitachycardia pacing. Results Among 394 ICD recipients (334 men, age 66.4 ± 11.0), fQRS was observed in 103 patients (26.1%). There were 189 patients (48.0%) with wide QRS at the time of implantation. Among these patients, fQRS was found in 29 individuals (28.2%). Patients in fQRS(+) group were more likely to have coronary artery disease and a lower QRS duration than those without fQRS. During a mean follow-up of 26.3 ± 17.5 months, mortality or ICD therapy were 19.4 and 22.4%, respectively, for fQRS(+) patients, and 15.2 and 22.8% for fQRS(−) patients (P = NS). By Kaplan–Meier analysis, event-free survival was similar in the two groups. Conclusion In ICD recipients for primary prevention of SCD, fQRS is not helpful in selecting a subgroup of patients who benefit from prophylactic ICD implantation.

Device monitoring of heart failure in cardiac resynchronization therapy device recipients: a single-center experience with a novel multivector impedance monitoring system.

Objectives We investigated the performance of a new intrathoracic multivector impedance monitoring system for the prediction of heart failure events in consecutive device-implanted patients. Methods Eighty heart failure patients implanted with biventricular defibrillators with multivector impedance monitoring capability were prospectively enrolled. Clinical heart failure status and impedance data were assessed during follow-up and if patients presented with an alert or heart failure deterioration. Results During follow-up (8.0 ± 4.4 months), 56 events of device alert for fluid index increase were identified in 29 patients, and a total of 39 heart failure events (defined by worsening of heart failure signs and symptoms) occurred in 23 patients. The sensitivity and positive predictive value (PPV) for heart failure deterioration was 61.5 and 42.9%, respectively. False-positive alerts occurred in 23 of 80 patients (28.8%), for an episode rate of 0.60 a year. Among all clinical heart failure events, decompensation caused hospitalization in 13 cases (33.3%), seven of them were preceded by an alert condition (53.8%) resulting in a sensitivity of 53.8% and a PPV of 17.9%. Conclusion The present study confirms the feasibility and clinical usefulness of this novel multivector impedance monitoring system. It would be worthwhile to perform larger studies to assess its actual clinical value in heart failure patients.

Work burden with remote monitoring of implantable cardioverter defibrillator. Is it time for reimbursement policies

Aims The efficacy and accuracy, as well as patients’ satisfaction, of device remote monitoring are well demonstrated. However, the workload of remote monitoring management has not been estimated and reimbursement schemes are currently unavailable in most European countries. This study evaluates the workload associated with remote monitoring systems. Methods A total of 154 consecutive implantable cardioverter defibrillator patients (age 66 ± 12 years; 86.5% men) with a remote monitoring system were enrolled. Data on the clinicians workload required for the management of the patients were analyzed. Results A total of 1744 transmissions were received during a mean follow-up of 15.3 ± 12.4 months. Median number of transmissions per patient was 11.3. There were 993 event-free transmissions, whereas 638 transmissions regarded one or more events (113 missed transmissions, 141 atrial events, 132 ventricular episodes, 299 heart failure-related transmissions, 14 transmissions regarding lead malfunction and 164 transmissions related to other events). In 402 cases telephonic contact was necessary, whereas in 68 cases an in-clinic visit was necessary and in 23 of them an in-clinic visit was prompted by the manufacturer due to technical issues of the transmitter. During follow-up, 316 work hours were required to manage the enrolled patients. Each month, a total of 14.9 h were spent on the remote monitoring of 154 patients (9.7 h for 100 patients monthly) with approximately 1.1 ± 0.15 h per year for each patient. Conclusion The clinicians work burden is high in patients with remote monitoring. In order to expand remote monitoring in all patients, reimbursement policies should be considered.

Systematic fluoroscopic and electrical assessment of implantable cardioverter-defibrillator patients implanted with silicone–polyurethane copolymer (Optim™) coated leads

AIMS Serious concerns have been recently raised about the reliability of the silicone-polyurethane copolymer (Optim™) lead insulation system. We sought to identify insulation defects and Optim-lead failures by systematic fluoroscopic and electrical assessment in a prospectively defined cohort of implantable cardioverter-defibrillator (ICD) patients. METHODS AND RESULTS Between July 2007 and December 2011, 234 patients were implanted with 413 optim-coated leads as part of an ICD system at a single centre. Fluoroscopic screening with high-resolution cine-fluoroscopy at 30 frames per second was offered to all patients. In addition, the electrical integrity of all implanted leads was assessed. Durata, Riata ST Optim, and low-voltage Optim leads were implanted in 199, 26, and 188 cases, respectively. During a total follow-up of 10 036 lead-months, there were 7 Optim-lead failures (defined as electrical malfunction resulting in lead replacement) and 31 deaths; no cases of electrical noises were encountered. The overall incidence of lead failure was 1.2 vs. 0.3 per 100 lead-years, for high- and low-voltage leads, respectively (P = 0.1). One hundred fifty-one patients agreed to undergo fluoroscopy screening; none of the 264 analysed Optim leads were found to have any fluoroscopically visible structural defects after an average of 31 months post-implant. CONCLUSION This study represents the first systematic screening of Optim-coated leads in a large unselected cohort of ICD patients. Over a 5-year period few lead failures were observed and normal fluoroscopic appearance was present in all patients.

A patient with asymptomatic cerebral lesions during AF ablation: How much should we worry?

Silent brain lesions due to thrombogenicity of the procedure represent recognized side effects of atrial fibrillation (AF) catheter ablation. Embolic risk is higher if anticoagulation is inadequate and recent studies suggest that uninterrupted anticoagulation, ACT levels above 300 seconds and administration of a pre-transeptal bolus of heparin might significantly reduce the incidence of silent cerebral ischemia (SCI) to 2%. Asymptomatic new lesions during AF ablation should suggest worse neuropsychological outcome as a result of the association between silent cerebral infarcts and increased long-term risk of dementia in non-ablated AF patients. However, the available data are discordant. To date, no study has definitely linked post-operative asymptomatic cerebral events to a decline in neuropsychological performance. Larger volumes of cerebral lesions have been associated with cognitive decline but are uncommon findings acutely in post-ablation AF patients. Of note, the majority of acute lesions have a small or medium size and often regress at a medium-term follow-up. Successful AF ablation has the potential to reduce the risk of larger SCI that may be considered as part of the natural course of AF. Although the long-term implications of SCI remain unclear, it is conceivable that strategies to reduce the risk of SCI may be beneficial.

Early detection of high voltage lead failure with an unusual and unexpected device alert

To the Editor Despite the positive effect on prevention of sudden cardiac death, implantable cardioverter defibrillator (ICD) therapy is associated with potential malfunctions of the implanted system. Although detected by electrical parameters during routine ICD controls, lead defects are recognised after the occurrence of inappropriate shocks in a significant proportion of patients. Various alert features have been implemented in newer generation ICDs in order to improve the management of device-implanted patients and provide early warnings of lead dysfunction. Recently, ICDs with the ability of continuous ST-segment monitoring through the ventricular lead have been developed. These devices continuously …