Clinical implications of elective replacement indicator setting changes in patients with dual-chamber pacemaker devices.

OBJECTIVE: This study sought to determine if single-chamber operation and/or loss of rate response (RR) during elective replacement indicator (ERI) in patients with dual-chamber pacemakers lead to increased symptom burden, healthcare utilization, and atrial fibrillation (AF). BACKGROUND: Dual-chamber pacemakers often change from dual- to single-chamber pacing mode and/or lose RR functionality at ERI to preserve battery. Single-chamber pacing increases the incidence of heart failure, AF, and pacemaker syndrome suggesting these changes may be deleterious. METHODS: A retrospective analysis of 700 patients was completed. Three comparisons were analyzed: Comparison 1: mode change and RR loss versus no change; Comparison 2: RR loss only versus no change; Comparison 3: mode change only versus no change (in patients with no RR programmed at baseline). RESULTS: In Comparison 1, 121 (46%) patients with setting changes experienced symptoms (most often dyspnea and fatigue/exercise intolerance) versus 3 (4%) without setting changes (p < .0001). Similar results were noted in Comparisons 2 and 3 (p = .0016 and p = .0001, respectively). In Comparison 1, patients with setting change sought provider contact more than patients without setting changes (p = .0001). A significant difference was not noted in Comparison 2 or 3. Overall 14 (2%) patients were hospitalized, all of whom had setting changes. CONCLUSIONS: Setting changes at ERI including a change from dual- to single-chamber pacing and/or loss of RR results in a significantly increased symptom burden and increased healthcare utilization.

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.

Single-Coil Defibrillator Leads Yield Satisfactory Defibrillation Safety Margin in Hypertrophic Cardiomyopathy.

BACKGROUND: Single-coil defibrillator leads have gained favor because of their potential ease of extraction. However, a high defibrillation threshold remains a concern in patients with hypertrophic cardiomyopathy (HCM), and in many cases, dual-coil leads have been used for this patient group. There is little data on using single-coil leads for HCM patients. METHODS AND RESULTS: We evaluated 20 patients with HCM who received an implantable cardioverter-defibrillator (ICD) on the left side in combination with a dual-coil lead. Two sets of defibrillation tests were performed in each patient, one with the superior vena cava (SVC) coil "on" and one with the SVC coil "off". ICDs were programmed to deliver 25 joules (J) for the first attempt followed by maximum energy (35 J or 40 J). Shock impedance and shock pulse width at 25 J in each setting as well as the results of the shock were analyzed. All 25-J shocks in both settings successfully terminated ventricular fibrillation. However, shock impedance and pulse width increased substantially with the SVC coil programmed "off" compared with "on" (66.4±6.1 ohm and 14.0±1.3 ms "off" vs. 41.9±5.0 ohm and 9.3±0.8 ms "on", P<0.0001 respectively). CONCLUSIONS: Biphasic 25-J shocks with the SVC coil 'off' successfully terminated ventricular fibrillation in HCM patients, indicating a satisfactory safety margin for 35-J devices. Single-coil leads appear appropriate for left-sided implantation in this patient group. (Circ J 2016; 80: 2199-2203).

Entrapment of a Pacing Lead within a Chiari Network: Utility of Intracardiac Echo and a Laser Sheath.

Although rare, Chiari networks are elaborate embryological remnants that can pose distinct challenges for catheter and pacing lead manipulation within the right atrium. Device entrapment may require open thoracotomy for removal, with significant morbidity. We report an unusual case of pacing lead entanglement within this structure, followed by prompt intracardiac echocardiographic identification and laser sheath removal.

Outcomes and Complications of Lead Removal: Can We Establish a Risk Stratification Schema for a Collaborative and Effective Approach?

BACKGROUND: Removal of an entire cardiovascular implantable electronic device is associated with morbidity and mortality. We sought to establish a risk classification scheme according to the outcomes of transvenous lead removal in a single center, with the goal of using that scheme to guide electrophysiology lab versus operating room extraction. METHODS: Consecutive patients undergoing transvenous lead removal from January 2001 to October 2012 at Mayo Clinic were retrospectively reviewed. RESULTS: A total of 1,378 leads were removed from 652 (age 64 ± 17 years, M 68%) patients undergoing 702 procedures. Mean (standard deviation) lead age was 57.6 (58.8) months. Forty-four percent of leads required laser-assisted extraction. Lead duration (P < 0.001) and an implantable cardioverter defibrillator (ICD) lead (P < 0.001) were associated with the need for laser extraction and procedure failure (P < 0.0001 and P = 0.02). The major complication rate was 1.9% and was significantly associated with longer lead duration (odds ratio: 1.2, 95% confidence interval: 1.1-1.3; P < 0.001). High-risk patients (with a >10-year-old pacing or a >5-year-old ICD lead) had significantly higher major events than moderate-risk (with pacing lead 1-10 years old or ICD lead 1-5 years old) and low-risk (any lead ≤1-year-old) patients (5.3%, 1.2%, and 0%, respectively; P < 0.001). CONCLUSIONS: Transvenous lead removal is highly successful, with few serious procedural complications. We propose a risk stratification scheme that may categorize patients as low, moderate, and high risk for lead extraction. Such a strategy may guide which extractions are best performed in the operating room.

Predictors and outcomes of "super-response" to cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) has been shown to improve heart failure (HF) symptoms and survival. We hypothesized that a greater improvement in left-ventricular ejection fraction (LVEF) after CRT is associated with greater survival benefit. METHODS AND RESULTS: In 693 patients across 2 international centers, the improvement in LVEF after CRT was determined. Patients were grouped as non-/modest-, moderate-, or super-responders to CRT, defined as an absolute change in LVEF of ≤5%, 6-15%, and >15%, respectively. Changes in New York Heart Association (NYHA) functional class and left ventricular end-diastolic dimension (LVEDD) were assessed for each group. There were 395 non-/modest-, 186 moderate-, and 112 super-responders. Super-responders were more likely to be female and to have nonischemic cardiomyopathy, lower creatinine, and lower pulmonary artery systolic pressure than non-/modest- and moderate-responders. Super-responders were also more likely to have lower LVEF than non-/modest-responders. There was no difference in NYHA functional class, mitral regurgitation grade, or tricuspid regurgitation grade between groups. Improvement in NYHA functional class (-0.9 ± 0.9 vs -0.4 ± 0.8 [P < .001] and -0.6 ± 0.8 [P = .02]) and LVEDD (-8.7 ± 9.9 mm vs -0.5 ± 5.0 and -2.4 ± 5.8 mm [P < .001 for both]) was greatest in super-responders. Kaplan-Meier survival analysis revealed that super-responders achieved better survival compared with non-/modest- (P < .001) and moderate-responders (P = .049). CONCLUSIONS: Improvement in HF symptoms and survival after CRT is proportionate to the degree of improvement in LV systolic function. Super-response is more likely in women, those with nonischemic substrate, and those with lower pulmonary artery systolic pressure.

Safety and outcomes of magnetic resonance imaging in patients with abandoned pacemaker and defibrillator leads.

INTRODUCTION: Abandoned cardiovascular implantable electronic device (CIED) leads remain a contraindication to magnetic resonance imaging (MRI) studies, largely due to in vitro data showing endocardial heating secondary to the radiofrequency field. We tested the hypothesis that abandoned CIED leads do not pose an increased risk of clinical harm for patients undergoing MRI. METHODS: This single-center retrospective study examined the outcomes of patients who had device generators removed before MRI, rendering the device leads abandoned. Information was gathered through chart review. Data collected included lead model, pacing threshold before MRI, anatomic region examined, threshold data after generator reimplantation, and clinical patient outcome. RESULTS: Patients (n = 19, 11 men and eight women) ranged in age from 19 to 85 at the time of MRI. There was a mean of 1.63 abandoned leads at the time of imaging; none of the leads were MRI conditional. Of the three implantable cardioverter defibrillator (ICD) leads, two of three were dual coil. Most (31/35) of the scans performed were of the central nervous system, including head and spinal imaging. There were no adverse events associated with MRI in any of these patients with abandoned leads within 7 days of the scan. No lead malfunctions or clinically significant change in pacing thresholds were noted with generator reimplantation. CONCLUSION: The use of MRI in patients with abandoned cardiac device leads appears feasible when performed under careful monitoring, with no adverse events, although the experience is small. MRI did not affect the function of leads that were subsequently reconnected to a cardiac device.

Cardiac magnetic resonance imaging pericardial late gadolinium enhancement and elevated inflammatory markers can predict the reversibility of constrictive pericarditis after antiinflammatory medical therapy: a pilot study.

BACKGROUND: Constrictive pericarditis (CP) is a disabling disease, and usually requires pericardiectomy to relieve heart failure. Reversible CP has been described, but there is no known method to predict the reversibility. Pericardial inflammation may be a marker for reversibility. As a pilot study, we assessed whether cardiac magnetic resonance imaging pericardial late gadolinium enhancement (LGE) and inflammatory biomarkers could predict the reversibility of CP after antiinflammatory therapy. METHOD AND RESULTS: Twenty-nine CP patients received antiinflammatory medications after cardiac magnetic resonance imaging. Fourteen patients had resolution of CP, whereas 15 patients had persistent CP after 13 months of follow-up. Baseline LGE pericardial thickness was greater in the group with reversible CP than in the persistent CP group (4 ± 1 versus 2 ± 1 mm, P = 0.001). Qualitative intensity of pericardial LGE was moderate or severe in 93% of the group with reversible CP and in 33% of the persistent CP group (P = 0.002). Cardiac magnetic resonance imaging LGE pericardial thickness ≥ 3 mm had 86% sensitivity and 80% specificity to predict CP reversibility. The group with reversible CP also had higher baseline C-reactive protein and erythrocyte sedimentation rate than the persistent CP group (59 ± 52 versus 12 ± 14 mg/L, P = 0.04 and 49 ± 25 versus 15 ± 16 mm/h, P = 0.04, respectively). Antiinflammatory therapy was associated with a reduction in C-reactive protein, erythrocyte sedimentation rate, and pericardial LGE in the group with reversible CP but not in the persistent CP group. CONCLUSIONS: Reversible CP was associated with pericardial and systemic inflammation. Antiinflammatory therapy was associated with a reduction in pericardial and systemic inflammation and LGE pericardial thickness, with resolution of CP physiology and symptoms. Further studies in a larger number of patients are needed.

Effect of long-term right ventricular pacing in young adults with structurally normal heart.

BACKGROUND: Right ventricular pacing increases the risk of heart failure in adults with structural heart disease. The impact of prolonged right ventricular pacing in adults without structural heart disease is not fully characterized and may depend on interactions of pacing with abnormal substrate predisposing to ventricular dysfunction. METHODS AND RESULTS: We assessed the effect of right ventricular pacing in patients who underwent pacemaker implantation for isolated congenital atrioventricular block between 1964 and 2005. To assess for immunologic contribution to cardiac dysfunction, outcomes were compared between patients with (Ab(+)) and without (Ab(-)) antinuclear antibody during adulthood and an age- and sex-matched Olmsted County, Minnesota, population. Of 103 patients (mean+/-SD age, 32+/-19 years), 18 were Ab(+). Long-term survival free of new heart failure after pacemaker implantation in isolated congenital atrioventricular block patients was worse than in the matched population (P<0.001). This difference was attributable to the development of heart failure in 12 Ab(+) patients (67%; P<0.001), without differences between Ab(-) patients (2%) and the matched population (2%; P=0.7). Compared with baseline, at last follow-up, left ventricular ejection fraction did not decline in Ab(-) (53+/-9% to 57+/-12%) but decreased in Ab(+)(52+/-10% to 38+/-12%; P=0.03) patients. Survival was similar in Ab(-) patients and the Minnesota population (98%; P=0.7) but worse in Ab(+) patients (79%; P<0.01). CONCLUSIONS: The natural history of patients with isolated congenital atrioventricular block who require pacing depends upon their antibody status. Antinuclear antibody status was a predictor for the development of heart failure and death. Long-term right ventricular pacing alone does not appear to be associated with development of heart failure, deterioration in ventricular function, or reduced survival in Ab(-) isolated congenital atrioventricular block patients.

Anodal stimulation: an underrecognized cause of nonresponders to cardiac resynchronization therapy.

OBJECTIVE: The purpose of this study was to determine if anodal stimulation accounts for failure to benefit from cardiac resynchronization therapy (CRT) in some patients. BACKGROUND: Approximately 30-40% of patients with moderate to severe heart failure do not have symptomatic nor echocardiographic improvement in cardiac function following CRT. Modern CRT devices allow the option of programming left ventricular (LV) lead pacing as LV tip to right ventricular (RV) lead coil to potentially improve pacing thresholds. However, anodal stimulation can result in unintentional RV pacing (anode) instead of LV pacing (cathode). METHODS: Patients enrolled in our center's CRT registry had an echocardiogram, 6-minute walk (6MW), and Minnesota Living with HF Questionnaire (MLHFQ) pre-implant and 6 months after CRT. Electrocardiograms (12 lead) during RV, LV, and biventricular (BiV) pacing were obtained at the end of the implant in 102 patients. Anodal stimulation was defined as LV pacing QRS morphology on EKG being identical to RV pacing or consistent with fusion with RV and LV electrode capture. LV end systolic volume (LVESV) was measured by echo biplane Simpson's method and CRT responder was defined as 15% or greater reduction in LVESV. RESULTS: Of the 102 patients, 46 (45.1%) had the final LV lead pacing configuration programmed LV (tip or ring) to RV (coil or ring). 3 of the 46 subjects (6.5%) had EKG findings consistent with anodal stimulation, not corrected intraoperatively. All anodal stimulation patients were nonresponders to CRT by echo criteria (reduction in LVESV 13.3 ± 0.6%, increase in EF 5.0 ± 1.4%) compared to 46% responders for those without anodal stimulation, (change in LVESV 18.7 ± 25.6%, EF 7.6 ±10.9%). None of the anodal stimulation patients were responders for the 6 minute walk, compared to 32 of 66 (48%) of those without anodal stimulation. CONCLUSION: Anodal stimulation is a potential underrecognized and ameliorable cause of poor response to CRT.

Temporal Incidence and Predictors of High-Grade Atrioventricular Block After Transcatheter Aortic Valve Replacement.

Background The temporal incidence of high-grade atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR) is uncertain. As a result, periprocedural monitoring and pacing strategies remain controversial. This study aimed to describe the temporal incidence of initial episode of HAVB stratified by pre- and post-TAVR conduction and identify predictors of delayed events. Methods and Results Consecutive patients undergoing TAVR at a single center between February 2012 and June 2019 were retrospectively assessed for HAVB within 30 days. Patients with prior aortic valve replacement, permanent pacemaker (PPM), or conversion to surgical replacement were excluded. Multivariable logistic regression was performed to assess predictors of delayed HAVB (initial event >24 hours post-TAVR). A total of 953 patients were included in this study. HAVB occurred in 153 (16.1%). After exclusion of those with prophylactic PPM placed post-TAVR, the incidence of delayed HAVB was 33/882 (3.7%). Variables independently associated with delayed HAVB included baseline first-degree atrioventricular block or right bundle-branch block, self-expanding valve, and new left bundle-branch block. Forty patients had intraprocedural transient HAVB, including 16 who developed HAVB recurrence and 6 who had PPM implantation without recurrence. PPM was placed for HAVB in 130 (13.6%) (self-expanding valve, 23.7% versus balloon-expandable valve, 11.9%; P<0.001). Eight (0.8%) patients died by 30 days, including 1 unexplained without PPM present. Conclusions Delayed HAVB occurs with higher frequency in patients with baseline first-degree atrioventricular block or right bundle-branch block, new left bundle-branch block, and self-expanding valve. These findings provide insight into optimal monitoring and pacing strategies based on periprocedural ECG findings.

Comparison of echocardiographic dyssynchrony assessment by tissue velocity and strain imaging in subjects with or without systolic dysfunction and with or without left bundle-branch block.

BACKGROUND: Several echocardiographic dyssynchrony indexes have been proposed to identify responders to cardiac resynchronization therapy using tissue velocity and strain. The present study aimed to compare tissue velocity-derived and strain-derived dyssynchrony indexes in patients with or without systolic dysfunction and left bundle-branch block. METHODS AND RESULTS: Tissue Doppler imaging was performed in 120 subjects divided into 4 groups: group 1 (n=40), normal subjects; group 2 (n=20), normal left ventricular ejection fraction and left bundle-branch block; group 3 (n=20), left ventricular ejection fraction <35% and normal conduction; and group 4 (n=40), left ventricular ejection fraction <35% and left bundle-branch block. Dyssynchrony indexes based on time to peak tissue velocity (septal-lateral delay, anteroseptal-posterior delay, and SD in time to peak systolic velocity in the 12 left ventricular segments) and strain (SD of time to peak strain in 12 segments) were measured. The SD in time to peak systolic velocity in the 12 left ventricular segments was greater in group 4 (54 ms; 25th and 75th percentiles, 46 to 64 ms) than group 1 (44 ms; 25th and 75th percentiles, 28 to 53 ms; P=0.006), but there was a considerable overlap of all tissue velocity-derived indexes among 4 groups, with 40% to 68% of group 1 having values proposed for predicting the responders of cardiac resynchronization therapy. The SD of time to peak strain in 12 segments distinguished these groups with much less overlap (P<0.01 for all pairwise comparisons). CONCLUSIONS: A substantial proportion of normal subjects have tissue velocity-derived dyssynchrony indexes higher than the cutoff value proposed for predicting beneficial effect of cardiac resynchronization therapy. Strain-derived timing index appears to be more specific for dyssynchrony in patients with systolic dysfunction and left bundle-branch block. Identifying an optimal tissue velocity- or strain-derived dyssynchrony index requires a large prospective clinical trial.

Pre- and post-pericardiocentesis echo-Doppler features of effusive-constrictive pericarditis compared with cardiac tamponade and constrictive pericarditis.

AIMS: To review 2D and Doppler findings in patients diagnosed with effusive-constrictive pericarditis (ECP) and compare these to patients with cardiac tamponade and patients with surgically-proven constrictive pericarditis (CP). METHODS AND RESULTS: We identified 22 patients diagnosed with ECP at Mayo Clinic, MN, USA between 2002 and 2016 who had persistent elevation of jugular venous pressure post-pericardiocentesis. We compared them to 30 patients with CP and 30 patients with cardiac tamponade who had normalization of venous pressure post-pericardiocentesis. All patients were in sinus rhythm. Mean age was 57 ± 18 years in the ECP group; 36% were females. Most ECP and cardiac tamponade cases were idiopathic (41% and 33%, respectively). Prior to pericardiocentesis, medial and lateral e' velocities were higher in ECP compared with tamponade; both ECP and tamponade patients had markedly decreased hepatic vein diastolic forward flow velocities. Inspiratory and expiratory mitral E/A ratios were higher in ECP compared with tamponade, but lower than those observed in CP. Post-pericardiocentesis, hepatic vein diastolic forward flow velocities increased in both ECP and tamponade. Hepatic vein diastolic reversal velocities decreased in tamponade but were unchanged in ECP. During median follow-up of 481 days, three patients required pericardiectomy for CP; they were all in the ECP group (14% of ECP cases). CONCLUSION: ECP may have unique echo-Doppler features that distinguish it from both CP and tamponade. Our findings suggest that ECP could be diagnosed by echocardiography even prior to pericardiocentesis. ECP appears to have a good prognosis, particularly in patients presenting acutely.

Efficacy and Safety of Transvenous Lead Extraction in the Device Laboratory and Operating Room Guided by a Novel Risk Stratification Scheme.

OBJECTIVES: The goal of this study was to evaluate a novel risk stratification scheme to categorize patients on the basis of risk to either an operating room or device laboratory with rescue strategy. BACKGROUND: Lead extraction can be complicated by lethal issues such as vascular and cardiac rupture. Currently, the optimal site for lead extraction has not been well established. METHODS: A risk stratification scheme was developed from previously available risk factors for major complications. Patients were prospectively risk stratified between October 2013 and January 2016. High-risk procedures were performed in the operating room with ready surgical services; intermediate-risk procedures were performed in the device laboratory. RESULTS: In total, 349 leads were removed from 187 patients (age 61.0 ± 17.2 years; 66.3% men) over 27 months. Seventy-two patients (38.5%) were categorized as high risk. Median implant duration of the oldest lead per patient was 11.2 years (interquartile range: 7.9 to 14.9 years) in the operating room group versus 2.6 years (interquartile range: 1.6 to 4.9 years) in the device laboratory group (p < 0.001). Clinical success in the operating room (95.8%) and device laboratory (99.1%) groups was similar (p = 0.16). A higher incidence of major complications occurred in the high-risk group (operating room group: 6.9%; device laboratory: 0.0%; p = 0.007). In-hospital mortality (operating room group: 8.3%; device laboratory: 2.6%; p = 0.09) and long-term (2-year) survival (operating room: 70.8%; device laboratory: 84.4%; p = 0.07) rates were similar. CONCLUSIONS: Use of a novel risk stratification scheme in guiding the selection of operating room versus device laboratory for lead extraction is feasible, safe, and efficacious. Intermediate-risk procedures can be performed safely in the device laboratory with rescue strategy, without excess surgical resource utilization.

Selecting the right defibrillator in the younger patient: Transvenous, epicardial or subcutaneous?

The advent of the subcutaneous implantable cardioverter-defibrillator (SQ-ICD) provides an alternative to transvenous and epicardial ICD therapy. Particularly germane to the young patient with congenital heart disease or inheritable arrhythmia syndromes, the SQ-ICD may be ideal for those who do not require permanent cardiac pacing. The serious complications associated with transvenous ICD systems are largely driven by the intravascular components of these devices and are avoided by this extravascular technique. Multiple clinical trials have shown that SQ-ICDs are effective in detecting and terminating ventricular arrhythmias, yet nuanced issues must be considered, especially in the context of congenital cardiovascular anomalies. This review aims to contextualize the role of this technology in contrast with traditional ICDs, and provide a logical approach to appropriate device selection.

Effusive-Constrictive Pericarditis After Pericardiocentesis: Incidence, Associated Findings, and Natural History.

OBJECTIVES: This study sought to investigate the incidence, associated findings, and natural history of effusive-constrictive pericarditis (ECP) after pericardiocentesis. BACKGROUND: ECP is characterized by the coexistence of tense pericardial effusion and constriction of the heart by the visceral pericardium. Echocardiography is currently the main diagnostic tool in the assessment of pericardial disease, but limited data have been published on the incidence and prognosis of ECP diagnosed by echo-Doppler. METHODS: A total of 205 consecutive patients undergoing pericardiocentesis at Mayo Clinic, Rochester, Minnesota, were divided into 2 groups (ECP and non-ECP) based on the presence or absence of post-centesis echocardiographic findings of constrictive pericarditis. Clinical, laboratory, and imaging characteristics were compared. RESULTS: ECP was subsequently diagnosed in 33 patients (16%) after pericardiocentesis. Overt clinical cardiac tamponade was present in 52% of ECP patients and 36% of non-ECP patients (p = 0.08). Post-procedure hemopericardium was more frequent in the ECP group (33% vs. 13%; p = 0.003), and a higher percentage of neutrophils and lower percentage of monocytes were noted on pericardial fluid analysis in those patients. Clinical and laboratory findings were otherwise similar. Baseline early diastolic mitral septal annular velocity was significantly higher in the ECP group. Before pericardiocentesis, respiratory variation of mitral inflow velocity, expiratory diastolic flow reversal of hepatic vein, and respirophasic septal shift were significantly more frequent in the ECP group. Fibrinous or loculated effusions were also more frequently observed in the ECP group. Four deaths occurred in the ECP group; all 4 patients had known malignancies. During median follow-up of 3.8 years (interquartile range: 0.5 to 8.3 years), only 2 patients required pericardiectomy for persistent constrictive features and symptoms. CONCLUSIONS: In a large cohort of unselected patients undergoing pericardiocentesis, 16% were found to have ECP. Pre-centesis echocardiographic findings might identify such patients. Long-term prognosis in those patients remains good, and pericardiectomy was rarely required.

Stroke in patients with cardiovascular implantable electronic device infection undergoing transvenous lead removal.

BACKGROUND: Stroke can be a devastating complication in patients with cardiovascular implantable electronic device (CIED) infection. Paradoxical septic embolism can occur in the presence of device leads and patent foramen ovale (PFO) via embolic dislodgment during transvenous lead removal (TLR). OBJECTIVE: The purpose of this study was to examine stroke and its associated factors in patients undergoing TLR for CIED infection. METHODS: We performed a retrospective analysis of all patients undergoing TLR for CIED infection from January 1, 2000, to July 30, 2017, from all 3 tertiary referral centers at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). The primary outcome was stroke and was further categorized into preprocedural and postprocedural stroke. Associated risk factors were analyzed. RESULTS: A total of 774 patients (mean age 67.6 ± 14.9 years) underwent TLR for CIED infection. The stroke rate in this cohort was 1.9% (95% confidence interval [CI] 1.1%-3.2%). The preprocedural and postprocedural stroke rate was 0.9% (95% CI 0.4%-1.9%) and 1.0% (95% CI 0.4%-2.0%), respectively. PFOs were identified in 46.7% of patients with stroke and in 12.9% of patients without stroke, and were independently associated with stroke (P = .0002). This was especially in patients with right-sided vegetations with right-to-left shunting (odds ratio 6.4; 95% CI 1.3-31.0; P = .022). CONCLUSION: In patients with CIED infection undergoing TLR, the presence of PFO, especially with right-sided vegetation with right-to-left shunting, was associated with an increased risk of stroke. This finding suggests that PFO screening before TLR warrants meticulous attention.

Response to cardiac resynchronization therapy predicts survival in heart failure: a single-center experience.

OBJECTIVE: To determine whether survival after cardiac resynchronization therapy (CRT) is related to improvement in clinical or echocardiographic parameters. BACKGROUND: In clinical trials, CRT improved symptoms, left ventricular (LV) structure, function, and survival. In clinical practice, response to CRT is highly variable and whether survival benefit is confined to those patients who experience improvement in clinical status or cardiac structure and function is unclear. METHODS: This is a single-center study of patients receiving clinically indicated CRT between January 2002 and December 2004. RESULTS: Of 309 patients (age 68 +/- 11 years, 83% male) receiving CRT at our institution during the study period, 174 returned for follow-up and 127 had repeat echocardiography. Baseline clinical characteristics and survival were similar among those who did or did not return for follow-up. In paired analyses, New York Heart Association (NYHA) class (-0.56 +/- 0.07, p < 0.0001), ejection fraction (EF, 6.3 +/- 0.7%, P < 0.0001), LV dimension (-2.7 +/- 0.6 mm, P < 0.0001), pulmonary artery systolic pressure (PASP, -4.6 +/- 1.3 mm Hg, P = 0.0007), and MR severity grade (-0.20 +/- 0.05, P = 0.0002) improved after CRT. Survival after CRT was associated with decrease in NYHA class (risk ratio [RR]= 0.43, P = 0.0004), increase in EF (RR = 0.94, P = 0.02), and decrease in PASP (RR = 0.96, P = 0.03). Change in EF and NYHA class were correlated (r = -0.46, P < 0.0001) and, adjusting for this covariance, change in NYHA (P = 0.04) but not EF (P = 0.12) was associated with improved survival. CONCLUSION: Patients who experience improved symptoms, ventricular function, and/or hemodynamics have better survival after CRT. These data enhance understanding of the relationship between CRT clinical response and survival benefit in clinical practice.

Right atrial lead fixation type and lead position are associated with significant variation in complications.

PURPOSE: Optimal atrial pacemaker lead position and fixation mechanism have not been determined with regard to effect on complications. We aimed to determine the association between atrial lead-related complications and varying atrial lead tip positions and lead fixation mechanisms. METHODS: All patients who underwent dual-chamber pacemaker implant between 2004 and 2014 were retrospectively reviewed for atrial lead tip position and fixation type. Lead-related complications were assessed by electronic medical record review. Complication rates were compared at 1 year by chi-square analysis and at 5 years using a Kaplan-Meier analysis. RESULTS: During the study period, 3451 patients (mean age 73.9, 53.4 % male) underwent dual-chamber pacemaker placement. Active fixation leads were associated with a higher incidence of pericardial effusion (81 (2.9 %) vs. 6 (1.0 %), p = 0.005) and pericardiocentesis (46 (1.6 %) vs. 2 (0.3 %), p = 0.01) at 1 year compared to passive fixation leads. There was no difference in overall complication rates by fixation type (161 (5.7 %) vs. 29 (4.6 %), p = 0.26). Low atrial septal lead tip position was associated with a higher rate of lead dislodgement (10 (15.2 %)) compared to appendage (46 (1.6 %)), free wall (10 (2.1 %)), or high atrial septal (2 (4.7 %)) positions (p < 0.001). This difference was also reflected in a significantly increased need for lead revision and overall complications. A multivariate analysis which included potential confounders confirmed the association of active fixation leads with an increased rate of perforation-related complications (p = 0.03) and septal lead location with increased rates of dislodgement (p < 0.001). CONCLUSIONS: Active compared to passive lead fixation increases the risk for pericardial effusion requiring pericardiocentesis. There is a clear association between low atrial septal lead position and lead dislodgement requiring lead revision.