Edmond M. Cronin

Clinical predictors of adverse patient outcomes in an experience of more than 5000 chronic endovascular pacemaker and defibrillator lead extractions

BACKGROUND It is difficult to predict adverse patient outcomes associated with transvenous lead extraction (TLE) procedures. OBJECTIVE The purpose of this study was to examine the safety and efficacy of chronic endovascular pacemaker and implantable cardioverter-defibrillator (ICD) lead extraction and risk factors associated with adverse patient outcomes. METHODS Consecutive patients undergoing TLE at the Cleveland Clinic between August 1996 and August 2011 were included in the analysis. Univariate and multivariable logistic regression analyses were performed to evaluate for associations with outcomes. Continuous data are given as median (25th, 75th percentile). Categorical data are given as number (percentage). RESULTS In total, 5521 leads (4137 [74.9%] pacemaker, 1384 [25.1%] ICD) were extracted during 2999 TLE procedures (patient age 67.2 [55.2, 76.2] years, 30.2% female). Lead implant duration was 4.7 (2.4, 8.3) years, and 2.0 (1.0, 2.0) leads were extracted per procedure. Powered sheaths were used in 74.9% of procedures. Overall, there was 95.1% complete procedural success, 98.9% clinical success, and 1.1% failure, with 3.6% minor complications and 1.8% major complications. All-cause mortality within 30 days of TLE was 2.2%. Multivariable predictors of major complications included cerebrovascular disease, ejection fraction ≤15%, lower platelet count, international normalized ratio ≥1.2, mechanical sheaths, and powered sheaths. Multivariable predictors of all-cause mortality within 30 days of TLE included body mass index <25 kg/m(2), end-stage renal disease, higher New York Heart Association functional class, lower hemoglobin, higher international normalized ratio, lead extraction for infection, and extraction of a dual-coil ICD lead. CONCLUSION TLE in this single-center experience was highly successful. Risk factors associated with adverse patient outcomes were identified.

Early Risk of Mortality After Coronary Artery Revascularization in Patients With Left Ventricular Dysfunction and Potential Role of the Wearable Cardioverter Defibrillator

Background—Implantation of implantable cardioverter defibrillator for prevention of sudden cardiac death is deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. We determined mortality risk in postrevascularization patients with left ventricular ejection fraction ⩽35% and compared survival with those discharged with a wearable cardioverter defibrillator (WCD). Methods and Results—Hospital survivors after surgical (coronary artery bypass graft surgery) or percutaneous (percutaneous coronary intervention [PCI]) revascularization with left ventricular ejection fraction ⩽35% were included from Cleveland Clinic and national WCD registries. Kaplan–Meier, Cox proportional hazards, propensity score-matched survival, and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared with 809 with WCDs (90-day mortality post–coronary artery bypass graft surgery 7% versus 3%, P=0.03; post-PCI 10% versus 2%, P<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, P<0.0001) and both post–coronary artery bypass graft surgery (38%, P=0.048) and post-PCI (57%, P<0.0001) cohorts (mean follow-up, 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post–coronary artery bypass graft surgery, P=0.002; 67% post-PCI, P<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy. Conclusions—Patients with left ventricular ejection fraction ⩽35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard seemed less marked in WCD users, prospective studies in this high-risk population are indicated to confirm whether WCD use as a bridge to left ventricular ejection fraction improvement or implantable cardioverter defibrillator implantation can improve outcomes after coronary revascularization.

Remote monitoring of cardiovascular devices: a time and activity analysis

BACKGROUND Expanding indications for cardiovascular implantable electronic devices are accompanied by an increasing burden of device clinic follow-up. Remote monitoring (RM) may be less time-consuming compared to in-office follow-up; however, its effect on the device clinic workflow has not been clarified. OBJECTIVE To determine the impact of RM on device clinic workflow. METHODS Detailed workflow data were prospectively collected over a 2-week period in a busy device clinic. RESULTS Five hundred remote transmissions were received from 434 patients between March 1 and March 16, 2011--346 implantable cardioverter-defibrillator, 84 pacemaker, and 70 implantable loop recorder transmissions--on 4 RM platforms (CareLink 56.4%, Merlin.net 21.4%, LATITUDE 17.8%, and Home Monitoring 4.4%). The mean time spent per transmission was 11.5 ± 7.7 minutes, which was less than in-person interrogations (27.7 ± 9.9 minutes; P <.01). Of 500 transmissions, 135 (27.0%) demonstrated clinically important findings; however, only 41 (8.2%) were forwarded for physician review. Of 500 transmissions, 138 (27.6%) were unscheduled, and these were more likely to contain a clinically important event (56 of 138 [40.6%] vs 79 of 362 [21.8%]; P = .0001). A total of 5.8% of the transmissions were duplicate. Transmissions that revealed clinically important findings took longer to process than those that did not (21.0 ± 7.4 minutes vs 10.1 ± 2.1 minutes; P <.05). A total of 49.2% of the scheduled remote transmissions were missed because of patient noncompliance. Telephone follow-up of patients (mean 21 patients/d) who missed scheduled remote transmissions took a mean of 55.1 (range 20-98) min/d. CONCLUSIONS Analysis of RM transmissions has significant implications for the device clinic workflow. Nonactionable transmissions are rapidly processed, allowing clinicians to focus on clinically important findings. However, poor patient compliance complicates the workflow efficiency of currently available systems.

Outcomes of patients requiring emergent surgical or endovascular intervention for catastrophic complications during transvenous lead extraction

BACKGROUND The outcomes of patients requiring emergent surgical or endovascular intervention during transvenous lead extraction (TLE) have not been well characterized. OBJECTIVES To evaluate the incidence of catastrophic complications requiring emergent surgical or endovascular intervention during TLE, to describe the injuries, and to review patient management and outcomes. METHODS Consecutive patients undergoing TLE of pacemaker and implantable cardioverter-defibrillator (ICD) leads at the Cleveland Clinic between August 1996 and September 2012 were included in the analysis. RESULTS A total of 5973 (4436 [74.3%] pacemaker and 1537 [25.7%] ICD) leads were extracted during 3258 TLE procedures (median [25th, 75th percentile] patient age 67.0 [55.0, 76.1] years; 69.2% men). The median (25th, 75th percentile) lead implant duration was 4.9 (2.4, 8.4) years, and 2.0 (1.0, 2.0) leads were extracted per procedure. Powered sheaths were used in 2369 (72.7%) procedures. Twenty-five (0.8%) patients experienced catastrophic complications requiring emergent surgical or endovascular intervention. Twenty patients (0.6%) required either sternotomy (n = 18) or thoracotomy (n = 2) for superior vena cava laceration (n = 15) and right atrial (n = 2) or ventricular (n = 3) perforation. Two patients required vascular repair at the procedural access site for either subclavian vein or artery laceration. Three patients were managed with an endovascular approach for superior vena cava laceration, left axillary artery laceration, and brachiocephalic vein and artery fistula. In-hospital mortality was 36.0% (6 procedural/operative deaths and 3 deaths during the same hospitalization). CONCLUSIONS Major vascular injury or cardiac perforation requiring emergent surgical or endovascular intervention during TLE is uncommon but carries significant in-hospital mortality. Despite high mortality, nearly two-thirds of these patients were rescued with immediate response and surgical or endovascular intervention.

Predictors of Response to Cardiac Resynchronization Therapy in Patients With a Non-Left Bundle Branch Block Morphology

Patients with non-left bundle branch block (LBBB) morphologies are thought to derive less benefit from cardiac resynchronization therapy (CRT) than those with LBBB. However, some patients do exhibit improvement. The characteristics associated with a response to CRT in patients with non-LBBB morphologies are unknown. Clinical, electrocardiographic, and echocardiographic data were collected from 850 consecutive patients presenting for a new CRT device. For inclusion, all patients had a left ventricular ejection fraction of ≤35%, a QRS duration of ≥120 ms, and baseline and follow-up echocardiograms available. Patients with a paced rhythm or LBBB were excluded. The response was defined as an absolute decrease in left ventricular end-systolic volume of ≥10% from baseline. Multivariate models were constructed to identify variables significantly associated with the response and long-term outcomes. A total of 99 patients met the inclusion criteria. Of these 99 patients, 22 had right bundle branch block and 77 had nonspecific intraventricular conduction delay; 52.5% met the criteria for response. On multivariate analysis, the QRS duration was the only variable significantly associated with the response (odds ratio per 10-ms increase 1.23, 95% confidence interval 1.01 to 1.52, p = 0.048). During a mean follow-up of 5.4 ± 0.9 years, 65 patients died or underwent heart transplant or left ventricular assist device placement. On multivariate analysis, the QRS duration was inversely associated with poor long-term outcomes (hazard ratio per 10-ms increase 0.79, 95% confidence interval 0.66 to 0.94, p = 0.005). In patients with advanced heart failure and non-LBBB morphologies, a wider baseline QRS duration is an important determinant of enhanced reverse ventricular remodeling and improved long-term outcomes after CRT.

Transvenous extraction of implantable cardioverter-defibrillator leads under advisory—A comparison of Riata, Sprint Fidelis, and non-recalled implantable cardioverter-defibrillator leads

BACKGROUND Comparative safety and efficacy associated with transvenous lead extraction (TLE) of recalled and non-recalled implantable cardioverter-defibrillator (ICD) leads has not been well characterized. OBJECTIVES To compare the indications, techniques, and procedural outcomes of recalled vs non-recalled ICD lead extraction procedures. METHODS TLE procedures performed at our institution from June 2002 to June 2012 in which Riata, Sprint Fidelis, or non-recalled ICD leads were extracted were included in the analysis. RESULTS ICD lead extraction procedures were performed in 1079 patients, including 430 patients with recalled leads (121 Riata, 308 Sprint Fidelis, and 1 Riata and Sprint Fidelis) and 649 patients with non-recalled ICD leads. A total of 2056 chronic endovascular leads were extracted, of which 1215 (59.1%) were ICD leads. Overall, there was 96.8% complete procedural success, 99.1% clinical success, and 0.9% failure, with 3.9% minor complications and 1.5% major complications. Procedural outcomes for Riata and Sprint Fidelis TLE procedures were no different. Lead implant duration was significantly less in recalled than in non-recalled ICD lead TLE procedures. Complete procedural success was higher in recalled (424 of 430 [98.6%]) than in non-recalled (621 of 649 [95.7%]; P = .007) ICD lead TLE procedures. Minor complications were lower in recalled (10 of 430 [2.3%]) than in non-recalled (32 of 649 [5.0%]; P = .030) ICD lead TLE procedures. Rates of clinical success, failure, and major complications were no different in the recalled and non-recalled ICD lead TLE procedures. CONCLUSION In our experience, recalled ICD leads were extracted with safety and efficacy comparable to that of non-recalled ICD leads.

Multicenter experience with extraction of the Riata/Riata ST ICD lead

BACKGROUND In November 2011, the Food and Drug Administration issued a class I recall of Riata and Riata ST implantable cardioverter-defibrillator leads. Management recommendations regarding the recall have remained controversial. OBJECTIVE Data regarding the safety and feasibility of extraction of Riata implantable cardioverter-defibrillator leads are limited. METHODS We performed a retrospective study of patients undergoing extraction of Riata/Riata ST leads at 11 centers. RESULTS Between July 2003 and April 2013, 577 Riata/Riata ST leads were extracted from 577 patients (Riata 467, [84%]; Riata ST 89, [16%]). Complete procedural success achieved in 99.1%. The cohort was 78% men, with a mean age of 60 years and a mean left ventricular ejection fraction of 34% ± 14%. The mean implant duration was 44.7 months (range 0-124.6 months). The majority of leads extracted were for infection (305 [53.0%]) and 220 (35.7%) for lead malfunction. Evaluation for lead integrity was performed in 295 cases. Of these, 34.9% were found to have externalized cables. Implant duration was significantly longer in leads with externalized cables (P < .0001). No difference in lead integrity was noted between Riata and Riata ST leads (11.7% vs. 17.7% failure; P = .23). Among leads in which cable externalization was noted, laser sheaths were used more frequently (P = .01). Major complications included 3 superior vena cava/right ventricular perforations requiring surgical intervention with 1 death 12 days after the procedure and 1 pericardial effusion requiring percutaneous drainage (0.87%). CONCLUSION Extraction of the Riata/Riata ST leads can be challenging, and leads with externalized cables may require specific extraction techniques. Extraction of the Riata/Riata ST leads can be performed safely by experienced operators at high-volume centers with a complication rate comparable to published data.

Impact of a National Smoking Ban on Hospital Admission for Acute Coronary Syndromes: A Longitudinal Study

A ban on smoking in the workplace was introduced in Ireland on March 29, 2004. As exposure to secondhand smoke has been implicated in the development of coronary disease, this might impact the incidence of acute coronary syndromes (ACS).

Cardiac venous left ventricular lead removal and reimplantation following device infection: a large single-center experience.

LV Lead Extraction and Reimplantation. Background: Early series of biventricular device removal have contained mostly younger cardiac venous (CV) left ventricular leads and few have reported on rates of successful reimplantation.

Magnetic resonance imaging conditional pacemakers: rationale, development and future directions.

Pacemakers and other cardiac implantable electronic devices (CIEDs) have long been considered an absolute contraindication to magnetic resonance imaging (MRI), a crucial and growing imaging modality. In the last 20 years, protocols have been developed to allow MR scanning of CIED patients with a low complication rate. However, this practice has remained limited to a relatively small number of centers, and many pacemaker patients continue to be denied access to clinically indicated imaging. The introduction of MRI conditional pacemakers has provided a widely applicable and satisfactory solution to this problem. Here, the interactions of pacemakers with the MR environment, the results of MR scanning in patients with conventional CIEDs, the development and clinical experience with MRI conditional devices, and future directions are reviewed.