Citations

Introduction: Right ventricular apical (RVA) pacing appears to have detrimental effects on cardiac function and long term outcomes. Right ventricular non-apical (RVNA) pacing, especially in the septal position, has been postulated as an alternative that may lead to less morbidity and mortality. Prior studies have shown conflicting results and been limited by small numbers and short follow-up. We aimed to determine if right ventricular septal lead position was associated with a reduction in long-term mortality compared to RVA lead position. Methods: Patients who underwent dual-chamber pacemaker implantation from 2004 through 2013 were evaluated for right ventricular lead position based on chest radiographs. Lead positions were divided in to apical or non-apical. Non-apical lead positions were subdivided to isolate a septal lead position group. Mortality was compared between these groups. Results: During the study period, 3456 patients underwent dual-chamber pacemaker placement and had images appropriate for lead position evaluation. The group was 53.5% male with a mean age of 74 ± 13 years. RVNA lead position was found in 976 (28.2%) patients, including 243 (7.0%) with a septal position. There was no significant difference in age or prior heart failure diagnosis between groups. Kaplan-Meier survival analysis did not reveal a significant difference in mortality between patients with RVA versus RVNA lead position during 5 year follow-up (p = 0.82). However, septal lead position was associated with a significantly lower mortality compared with RVA position (p = 0.03) (figure). Conclusions: Right ventricular septal lead position is associated with a lower long-term mortality than RVA lead position. This has substantial implications regarding the preferred site for ventricular pacing lead placement.

Introduction: Percutaneous epicardial access (EAc) is increasingly performed as part of VT/PVC ablation, especially in those that have failed prior ablation. We aimed to delineate the outcomes of EAc. Methods: We retrospectively analyzed individuals undergoing EAc for arrhythmia ablation between June 2004 and July 2014. Acute procedural success was defined as elimination/non-inducibility of the clinical arrhythmia after ablation; clinical success was defined as absence of symptoms/arrhythmia. Results: Of 175 patients, 126 (72%) were male with a mean age of 52.8±15.7 years. Eighty-three (47.4%) patients had NICM, 25 (14.3%) had ICM and 34 (19.4%) had normal hearts. Baseline EF was 44±16%. Patients had failed an average of 1.7±1.2 antiarrhythmic drugs; 139 patients (79%) had failed prior endocardial (endo) ablation (average 1.3±1.1). Six (3.4%) had prior EAc and 18 (10.3%) prior cardiac surgery. The indication for ablation was VT or PVC in 113 (64.6%) and 60 (34.3%) patients, respectively. Successful access was obtained in 168 (98%) patients. Anterior access, inferior access, or both, was utilized in 89 (52.7%), 77 (45.6%) and 2 (1.2%) patients, respectively. There were an average of 2.7±2.2 VT/PVCs identified, and 1.6±1.1 ablated. Endo, epicardial (epi) or combined ablation was performed in 58 (33.1%), 14 (8%), and 100 (57.1%) patients, respectively; 3 did not undergo ablation. Procedural success was obtained in 158 of 173 (91.3%) patients for whom data was available. At 12 months, clinical success was maintained in 62% with no difference between endo, epi or combined ablation (figure). Cardiac tamponade requiring repeat EAc occurred in 12 (6.9%) patients. There were no procedural related deaths. Conclusion: Epicardial access is feasible in almost all patients with no prior cardiac surgery, and permits acute procedural success in 91.3% of patients, most of whom had failed previous ablation. Furthermore, complications are relatively infrequent in this complex cohort.

Introduction: Patients with congenital heart disease (CHD) frequently require implantable cardiac devices. Device infection or malfunction may necessitate lead extraction. Extraction may be challenging due to long lead dwell times, anatomic abnormalities, and prior cardiac surgery. Little is known about extraction outcomes in the CHD population. Methods and Results: This retrospective study included 41 CHD patients and 82 age and gender matched controls that underwent lead extractions at two centers between 2001-2014. Only patients with leads older than 12 months were included. There were 79 leads in CHD patients and 150 in controls. Patients with CHD had a mean age of 39±17 years at extraction and on average their leads had been implanted for 81±84 months, this was not significantly different from the control group. Eighty eight percent of CHD patients had 1 or more cardiac surgeries as compared to only 22% of controls (p<0.001). The number of abandoned leads was also significantly different with 16 abandoned leads in the CHD group and 3 in controls (p<0.001). There was no statistically significant difference in extraction techniques between the groups. Complete extraction was achieved in 94% of patients in both groups. There were no CHD group complications. Control group complications included 3 SVC lacerations requiring sternotomy (one was fatal), and 1 ventricular perforations with tamponade requiring sternotomy. None of these patients had a history of cardiac surgery. The average age of leads in patients with a complication was 15.3 years which was older than the mean lead age seen in the CHD and control populations which was 6.75 and 4.6 years respectively. Conclusions: Lead extraction can be safely performed in patients with CHD. Despite anatomic abnormalities and previous cardiac surgery, the outcome of lead extraction in patients with CHD is comparable to controls. Prior cardiac surgery may lower the risk for extraction complications.

Introduction Left ventricular non-compaction (LVNC) is a rare cardiomyopathy thought to result from intrauterine arrest of myocardial compaction which has been associated with and increased risk of sudden cardiac death (SCD). However, appropriate identification of at-risk individuals and risk-stratification is lacking, particularly in patients diagnosed during adulthood. We sought to identify high-risk patients wtih LVNC in order to guide therapy. Hypothesis That patients with decreased left ventricular ejection fraction (LVEF) would have worse outcomes than those with preserved left ventricular function. Methods We reviewed outcomes in all patients diagnosed with LVNC at Mayo Clinic between 2001 through 2006. Data were prospectively entered into a centralized database and retrospectively analyzed. Mortality was compared to age and sex matched population rates. Results A total of 80 patients were diagnosed with LVNC during this interval. After exclusion of pediatric patients (n = 21), 59 adult patients (62% male; age 46 ± 19 years, range 18–83) were analyzed. There were 4 deaths in this group (none due to stroke, mortality 18% at 2 years) during follow-up (mean 13.0 ± 13.5 months, range 0–52). Overall survival of patients with LVNC was worse than age and sex matched controls (Minnesota population p < 0.001). This was also noted in patients with LVEF > 35% (n = 35, p = 0.02). Overall LVEF was 41 ± 16% but was lower in patients who died compared to survivors (26 ± 10% vs. 42 ± 15%; Hazard ratio = 2.0 for a decrease in ejection fraction of 10%, p = 0.12). There were no deaths in patients with LVEF > 50% (n = 17). Conclusion Survival of adults with LVNC is worse than expected for age and sex. A decrease in ejection fraction is associated with increased risk of death in this population. These data suggest that patients diagnosed with LVNC and reduced LVEF may benefit from ICD implantation, whereas patients with a normal LVEF may be observed.

Objective To review the long-term functional outcomes of patients with Ebstein anomaly who had cardiac surgery at our institution. Methods From April 1, 1972 to January 1, 2006, 539 patients with Ebstein anomaly had 604 cardiac operations at Mayo Clinic Rochester. The 506 late survivors form the basis of this report. Patient records were reviewed and all patients were mailed a medical questionnaire or contacted by telephone. Patients who had associated complex congenital heart disease were excluded (pulmonary atresia, conotruncal abnormalities, and atrioventricular discordance and ventriculoarterial discordance). Results At the initial operation at our institution, the mean age was 24 years (range 8 days to 79 years) and 53% were female. Survival at 5, 10, 15, and 20 years was 94%, 90%, 86%, and 76%. Survival free of late reoperation was 86%, 74%, 62%, and 46% at 5, 10, 15, and 20 years respectively. Surveys were returned by 285 patients. Two hundred and thirty-seven (83%) of patients were in NYHA class I or II and 34% were taking no cardiac medication. Five patients (2%) reported having endocarditis, 1 patient (<1%) reported a stroke, and 103 patients (36%) had atrial fibrillation or flutter. There were a total of 202 pregnancies among 82 women. Recurrence of congenital heart disease was low. Only 9/232 (0.04%) of liveborn children had congenital heart disease. Conclusions Patients have good long term survival and functional outcomes, after operation for Ebstein anomaly. Atrial arrhythmias are relatively common both before and after operation. Pregnancy appears to be well tolerated with low recurrence risk of congenital heart disease.

Background : Unrecognized myocardial infarction (UMI), as diagnosed by surveillance electrocardiography (ECG), has the same poor prognosis as recognized (RMI), independent of ejection fraction or ischemia. The value of post UMI risk stratification by infarct size is unknown. Methods : The study group consisted of 5430 patients who underwent 2 day stress (exercise n = 191, pharmacologic n = 155) and rest Tc-99m sestamibi SPECT studies. UMI was diagnosed if ECG showed Q wave MI in the absence of history of MI. SPECT infarct size was quantitated based on a 60% of peak counts threshold method and was expressed as a percentage of the left ventricle (% LV). The association between infarct size and mortality was adjusted for clinical and exercise test prognostic scoring systems. Results : The population consisted of 346 UMI, 628 RMI, and 4456 patients without MI (No MI). Compared to No MI, mortality risk was increased in UMI (RR 1.7, 95% CI 1.6–1.9; p < 0.001) and RMI (RR 1.6, 95% CI 1.4–1.9; p < 0.001) patients. In the UMI group, infarct size was significantly associated with mortality ( p < 0.001), which persisted after adjustment for Mayo prognostic score alone (available in all patients) ( p < 0.001) and for Mayo prognostic score, Framingham risk score, and Duke treadmill score (data available in 137 patients) ( p < 0.001). For every 10% LV increase in infarct size, mortality risk increased 30% (RR = 1.3, 95% CI 1.2–1.5) (see figure ). Conclusions: In patients with UMI, larger quantitated SPECT infarct size predicts increased mortality independent of clinical and exercise test prognostic scoring systems. This finding supports the use of infarct size imaging for risk stratification of UMI patients.

Introduction: Left atrial appendage (LAA) flow depends largely on left ventricular compliance and may play a role in mediating the regulation of left atrial volume-pressure relationships. Hypothesis: We hypothesize that LAA emptying flow velocity (LAAEV) is a predictive factor of long-term outcomes (e.g. recurrent AF, stroke, and survival) after cardioversion for non-valvular AF. Method: We identified 3,251 consecutive patients with non-valvular AF who underwent successful TEE-guided electrical cardioversion (ECV) at our institution between May 2000 and March 2012. Successful ECV was defined as sinus rhythm at time of discharge from the cardioversion unit. Patients were monitored following their ECV procedure for first documentation of recurrent AF, stroke or death. Multivariate Cox proportional hazards models were used to identify independent predictors of long-term outcomes. Patients with >= moderate valvular regurgitation or stenosis were excluded. Results: Among the 3,251 patients who were successfully cardioverted to sinus rhythm, the mean (±SD) LAAEV was 38.43±23 cm/s and the median was 33 cm/s, (interquartile range [IQR], 20-50). Patients with LAAEV <=33 cm/s had higher CHA 2 DS 2 -VASc score (2.6±1.2 vs. 1.9±1.3, P =.009), larger LAVI (52.0±20.9 cc/m 2 vs. 43.3±13.6 cc/m 2 , P <.001) than those with LAAEV >33 cm/s. Pre or post-procedure antiarrhythmic drug use was similar between the two groups. During 1-year follow-up, patients with LAAEV <=33 cm/s had significantly higher rate of AF recurrence than those with LAAEV >33 cm/s (55% vs 45%, P <.001). Likewise, during a mean follow-up of 4.9±3.6 years, similar patterns in 5-year rates were observed for first recurrence of AF (81% vs 73%, P <.001), stroke (7% vs 4%, P =.003) and mortality (31% vs 23%, P <.001) for LAAEV <=33 vs > 33cm/s, respectively. Stepwise multivariate Cox regression analysis revealed that LAAEV <=33 cm/s, age, CHA 2 DS 2 -VASc score were independent predictors of AF recurrence, stroke and mortality. Conclusions: LAA emptying flow velocity is an effective and convenient method for risk stratification of patients undergoing cardioversion for AF. Our data showed that patients with reduced LAAEV have an increased risk for AF recurrence, stroke and death following electrical cardioversion.

Background— The Bypass Angioplasty Revascularization Investigation trial demonstrated that symptomatic diabetics with multivessel coronary artery disease had a survival advantage with initial coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI). No published study has examined different treatments and outcome in asymptomatic diabetics. Methods and Results— This study group consisted of 826 asymptomatic diabetics (age 62±12 years; 76% men) without known coronary artery disease who had abnormal myocardial perfusion during stress single photon emission computed tomography (SPECT). SPECT images were classified as low-, intermediate-, and high-risk. Early revascularization (CABG or PCI ≤4 months after SPECT) was performed in 76 patients. Survival (follow-up, 5.3±3.3 years) was compared in patients treated with CABG, PCI, or medical therapy. Revascularization (CABG or PCI) was performed in 54 of 261 patients with high-risk scans and was independently associated with improved survival (χ 2 =4.55; P =0.03 after multivariate adjustment). Subset analysis demonstrated that the survival advantage was confined to patients treated with CABG (n =39), with a 5-year survival CABG at 85%, PCI at 72%, and medical therapy at 67% ( P =0.02 for 3 groups). Although CABG was associated with better survival, mortality remained high (3% per year). There was no survival advantage by treatment for patients with less-severe SPECT abnormalities. Conclusions— These nonrandomized data suggest that CABG improves survival in asymptomatic diabetic patients with high-risk SPECT, although revascularization was performed infrequently in these patients. These results parallel those of the Bypass Angioplasty Revascularization Investigation trial in symptomatic diabetic patients.