Mulpuru, Siva K.

BACKGROUND: The incidence and prognosis of right bundle branch block (RBBB) following transcatheter aortic valve replacement (TAVR) are unknown. Hence, we sought to characterize the incidence of post-TAVR RBBB and determine associated risks of permanent pacemaker (PPM) implantation and mortality. METHODS: All patients 18 years and above without preexisting RBBB or PPM who underwent TAVR at US Mayo Clinic sites and Mayo Clinic Health Systems from June 2010 to May 2021 were evaluated. Post-TAVR RBBB was defined as new-onset RBBB in the postimplantation period. The risks of PPM implantation (within 90 days) and mortality following TAVR were compared for patients with and without post-TAVR RBBB using Kaplan-Meier analysis and Cox proportional hazards modeling. The risks of PPM implantation (within 90 days) and mortality following TAVR were compared for patients with and without post-TAVR RBBB using Kaplan-Meier analysis and Cox proportional hazards modeling. RESULTS: Of 1992 patients, 15 (0.75%) experienced new RBBB post-TAVR. There was a higher degree of valve oversizing among patients with new RBBB post-TAVR versus those without (17.9% versus 10.0%; P =0.034). Ten patients (66.7%) with post-TAVR RBBB experienced high-grade atrioventricular block and underwent PPM implantation (median 1 day; Q1, 0.2 and Q3, 4), compared with 268/1977 (13.6%) without RBBB. Following propensity score adjustment for covariates (age, sex, balloon-expandable valve, annulus diameter, and valve oversizing), post-TAVR RBBB was significantly associated with PPM implantation (hazard ratio, 8.36 [95% CI, 4.19–16.7]; P <0.001). No statistically significant increase in mortality was seen with post-TAVR RBBB (hazard ratio, 0.83 [95% CI, 0.33–2.11]; P =0.69), adjusting for age and sex. CONCLUSIONS: Although infrequent, post-TAVR RBBB was associated with elevated PPM implantation risk. The mechanisms for its development and its clinical prognosis require further study.

Background: Long-term outcomes of lead management strategies of lead abandonment (LA) or transvenous lead extraction (TLE) during cardiac implantable electronic devices (CIED) procedures requiring lead addition or replacement remain unclear. Hypothesis: We hypothesized that there is no difference in long-term (10-year) outcomes of LA versus TLE during CIED procedures requiring lead addition. Methods: We performed a retrospective cohort study of a population residing in seven adjacent counties of southeastern Minnesota with follow-up at the Mayo Clinic and its health systems. Patients who underwent LA or TLE for sterile leads from January 1, 2000, to January 1, 2011, and had follow-up for at least 10-years or until their death were included. Outcomes were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system. Results: A total of 172 patients were included in the study with 153 patients who underwent LA and 19 who underwent TLE for sterile leads. In long-term follow-up, indications for subsequent lead extraction arose in 9.1% (n=14) of patients with initial LA and 5.3% (n=1) in patients with initial TLE, after an average of 7-years. Moreover, out of 14 patients, who required secondary extraction in the LA cohort, 28.6% did not proceed with the extraction. Of the remaining 10 patients, 60% had clinical success and 40% had a clinical failure with the extraction. Subsequent device upgrades or revisions were performed in 18.3% of patients in the LA group and 31.6% in the TLE group, with no significant differences in procedural challenges such as requiring balloon venoplasty or serial dilation (5.2% vs. 5.3%, P=1.0). There was no difference in 10-year survival probability among LA group and TLE group (P=0.64). Conclusion: Indications for subsequent extraction arose in 9.1% of patients with the initial LA approach for sterile leads after an average of 7.3 years and 28.6% did not proceed with the extraction. Of the patients who underwent the subsequent extraction, 60% had clinical success and 40% had a clinical failure. There was no difference in 10-year survival probability between patients with the initial LA approach or TLE approach.

Background: Recognition of the causes of early mortality after atrial fibrillation (AF) catheter ablation is essential for the improvement of patient safety. Objective: This study sought to determine the causes of early mortality (≤90-days) after AF ablation and to further understand the circumstances surrounding death after the procedure. Methods: We performed a retrospective analysis of AF ablation from January 1, 2013, to December 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a comprehensive chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 6,723 patients were included in the study. The 30-day and 90-day all-cause mortality rates were 0.09% and 0.22%, respectively. Among all 90-day deaths, majority of the deaths (73.3%) did not have a direct relationship with the procedure. Sudden death was the most common cause of early death (20%), followed by peri-procedural stroke (13%), respiratory failure (13%), atrioesophageal fistula (13%), infection (7%), heart failure (7%), and traumatic brain injury (7%). The 90-day mortality rate directly due to AF ablation procedural complications was 0.06%. Most of the early deaths (93.3%) occurred after discharge from index hospitalization, among which 64.3% were readmitted before their death, 14% died at home, and 7% were discharged on comfort care and died in hospice. The main reason for readmission leading to death was respiratory failure (33%). Conclusion: Atrial fibrillation ablation procedure has a 90-day mortality of 0.22% and the most common cause of early mortality was sudden death. The majority (73.3%) of early mortality was not directly associated with a procedural complication, and the mortality rate due to complications associated with the AF ablation procedure was 0.06%.

Background: Recognition of the causes of early mortality after ventricular tachycardia (VT) ablation in patients with reduced left ventricular ejection fraction is an essential step toward improving post-procedural outcomes. Objective: This study sought to determine the causes of early mortality (≤30-days) after VT ablation in patients with reduced left ventricular ejection fraction and to understand further the circumstances surrounding death after the procedure. Methods: We performed a retrospective analysis of all patients undergoing VT ablation in patients with reduced left ventricular ejection fraction from January 1, 2013, to November 10, 2021, at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a detailed chart review of the electronic health record within the Mayo Clinic system and outside records. Results: A total of 503 patients (mean age 63 ± 13 years, 11.2% female) with EF <50% were included in the study. The 30-day all-cause mortality rate was 5% (n=25), and the mortality rate due to a procedural complication was 0.4%. Among all 30-day deaths, recurrent VT was the most common primary cause of death (44%). This was followed by decompensated heart failure (28%), procedure-related death (8%), cerebrovascular accident (CVA) (4%), and infection (4%). Most patients (91%) who died from VT had the VT recurrence within three days of the ablation. 76% of patients with early mortality had delayed referral for VT ablation, and 72% opted for comfort care before death. Conclusions: The overall early mortality (≤30-days) rate after catheter ablation of VT in patients with reduced left ventricular ejection fraction was 5%, but the death rate directly due to a procedural complication was only 0.4%. The most common cause of death was recurrent VT, followed by heart failure. Further research into ablation strategies is vital to improving the safety, efficacy, and durability of VT ablation.

Background: Recognition of the infectious characteristics among the sepsis-related early mortality after transvenous lead removal (TLR) is an essential step to improving patient outcomes. Objective: This study sought to understand the infectious characteristic and circumstances among the sepsis-related early mortality after TLR. Methods: We performed a retrospective analysis of all patients undergoing TLR from January 1, 2001, to January 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Patient details were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 2,319 patients were included in the study. The overall 30-day sepsis-related mortality rate was 1.25% (n=29). Among the sepsis-related deaths, 24 patients (83%) had systemic cardiac implantable electronic device (CIED) infection, and 4 patients (14%) initially had isolated pocket infection. The average time from admission to TLR was 11 days. MSSA was the most common organism (n=8, 28%), and this was followed by MRSA (n=4, 14%) and Candida (n=3, 10%). Twenty of these patients (69%) had vegetation on the echocardiogram: vegetation on lead only in 9 patients, vegetation on both valve and lead in 8 patients, and vegetation on valve only in 3 patients. Among valvular vegetations, 5 patients had tricuspid valve vegetations, 3 patients had aortic valve vegetations, 2 patients had mitral valve vegetations, and 1 patient had both mitral and aortic valve vegetation. The average size of vegetation was 1.3±0.8 x 1.1±0.6 cm. Conclusions: The 30-day sepsis-related mortality rate was 1.25%. Among the sepsis-related early deaths, MSSA was the most common organism, and more than two-thirds (69%) of the patients had vegetations on cardiac imaging. This highlights the importance of further research to improve the infection outcome in TLR patients.

Background: Recognition of the causes of early mortality after transvenous lead removal (TLR) is an essential step for the development of quality improvement programs. Objective: This study sought to determine the causes of early mortality after TLR and to further understand the circumstances surrounding death after TLR. Methods: We performed a retrospective analysis of all patients undergoing TLR from January 1, 2001, to January 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system and outside records when available. The causes of death were further characterized based on whether it was related to the TLR procedure. Results: A total of 2,319 patients were included in the study. The overall 30-day all-cause mortality rate was 3%. Among all 30-day deaths, infection was the most common primary cause of death (42%). This was followed by decompensated heart failure (17%), procedure-related death (10%), sudden cardiac arrest (7%), and respiratory failure (6%). The 30-day mortality rate directly due to complications associated with the TLR procedure was 0.3% due to vascular tear and cardiac perforation. A third of deaths (33%) occurred after discharge from index hospitalization, among which 43% were readmitted before their death, 35% died at home or a nursing facility, and 22% were discharged on comfort care and died in hospice. The main reasons for readmission prior to death were sepsis and decompensated heart failure. Conclusions: The majority (90%) of 30-day mortality after TLR was not due to complications associated with TLR procedures. The primary causes were infection and decompensated heart failure. This highlights the importance of further research to reduce postoperative mortality from these factors, including deaths after hospital discharge.

Background: Recognition of the causes of early mortality after atrial fibrillation (AF) catheter ablation is essential for the improvement of patient safety. This study sought to determine the causes of early mortality (≤90 days) after AF ablation. Methods: We performed a retrospective analysis of AF ablation from January 1, 2013, to December 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a comprehensive chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 6723 patients were included in the study. The 90-day all-cause mortality rate was 0.22% (n=15). Among all 90-day deaths, majority of the deaths (73.3%) did not have a direct relationship with the procedure. Sudden death was the most common cause of early death (20%), followed by peri-procedural stroke (13%), respiratory failure (13%), atrioesophageal fistula (13%), infection (7%), heart failure (7%), and traumatic brain injury (7%). The 90-day mortality rate directly due to AF ablation procedural complications was 0.06% (n=4). Conclusions: AF ablation procedure has a 90-day mortality of 0.22%, and the most common cause of early mortality was sudden death. The majority (73.3%) of early mortality was not directly associated with a procedural complication, and the mortality rate due to complications associated with the AF ablation procedure was low at 0.06%. Further studies are required to investigate causes and risk factors associated with sudden death in this patient population.

AbstractIntroductionData regarding ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation in patients with aortic valve (AV) intervention (AVI) is limited. Catheter ablation (CA) can be challenging given perivalvular substrate in the setting of prosthetic valves. We sought to investigate the characteristics, safety, and outcomes of CA in patients with prior AVI and ventricular arrhythmias (VA).MethodsWe identified consecutive patients with prior AVI (replacement or repair) who underwent CA for VT or PVC between 2013 and 2018. We investigated the mechanism of arrhythmia, ablation approach, perioperative complications, and outcomes.ResultsWe included 34 patients (88% men, mean age 64 ± 10.4 years, left ventricular (LV) ejection fraction 35.2 ± 15.0%) with prior AVI who underwent CA (22 VT; 12 PVC). LV access was obtained through trans‐septal approach in all patients except one patient who had percutaneous transapical access. One patient had combined retrograde aortic and trans‐septal approach. Scar‐related reentry was the dominant mechanism of induced VTs. Two patients had bundle branch reentry VTs. In the VT group, substrate mapping demonstrated heterogeneous scar that involved the peri‐AV area in 95%. Despite that, the site of successful ablation included the periaortic region only in 6 (27%) patients. In the PVC group, signal abnormalities consistent with scar in the periaortic area were noted in 4 (33%) patients. In 8 (67%) patients, the successful site of ablation was unrelated to the periaortic area. No procedure‐related complications occurred. The survival and recurrence‐free survival rate at 1 year tended to be lower in VT group than in PVC group (p = .06 and p = .05, respectively) with a 1‐year recurrence‐free survival rate of 52.8% and 91.7%, respectively. No arrhythmia‐related death was documented on long‐term follow‐up.ConclusionCA of VAs can be performed safely and effectively in patients with prior AVI.

AbstractBackgroundThe incidence and impact of noise in a subcutaneous implantable cardioverter defibrillator (S‐ICD) after left ventricular assist device (LVAD) implantation is not well established.MethodsWe performed a retrospective study of patients implanted with LVAD and with a pre‐existing S‐ICD between January 2005 and December 2020 at the three Mayo Clinic centers (Minnesota, Arizona, and Florida).ResultsOf the 908 LVAD patients, a pre‐existing S‐ICD was present in 9 patients (mean age 49.1 ± 13.7 years, 66.7% males), 100% with Boston Scientific third‐generation EMBLEM MRI S‐ICD, 11% with HeartMate II (HM II), 44% with HeartMate 3 (HM 3), and 44% with HeartWare (HW) LVAD. The incidence of noise from LVAD‐related electromagnetic interference (EMI) was 33% and was only seen with HM 3 LVAD. Multiple measures attempted to resolve noise, including using alternative S‐ICD sensing vector, adjusting S‐ICD time zone, and increasing LVAD pump speed, were unsuccessful, necessitating S‐ICD device therapies to be turned off permanently.ConclusionsThe incidence of LVAD‐related S‐ICD noise is high in patients with concomitant LVAD and S‐ICD with significant impact on device function. As conservative management failed to resolve the EMI, the S‐ICDs had to be programmed off to avoid inappropriate shocks. This study highlights the importance of awareness of LVAD‐SICD device interference and the need to improve S‐ICD detection algorithms to eliminate noise.