Idiopathic Ventricular Fibrillation in a Previously Healthy Recreational Athlete.

There are several clinical challenges in the survivor of sudden cardiac arrest (SCA), including ensuring that a comprehensive diagnostic evaluation has been performed and providing counseling on return to activity. We report a case of a highly conditioned athlete who presented following aborted SCA during exercise with a diagnosis of idiopathic ventricular fibrillation arrest. (Level of Difficulty: Intermediate.).

Risk Factors for Repeat Infection and Mortality After Extraction of Infected Cardiovascular Implantable Electronic Devices.

OBJECTIVES: This study sought to investigate the factors associated with repeat infection following lead extraction procedures. BACKGROUND: Although lead extraction is an essential therapy for patients with cardiovascular implantable electronic device (CIED) infection, repeat infection still occurs in some patients. METHODS: The authors reviewed data for consecutive patients who underwent extraction of infected CIEDs from August 2003 to May 2019. Repeat infection was defined as infective endocarditis, sepsis with no alternative focus, or pocket infection after extraction of infected CIEDs. RESULTS: Extraction of infected CIEDs was performed in 496 patients. The most commonly implicated pathogen was Staphylococcus aureus (n = 188). In 449 patients (90.5%), all leads were completely extracted using only transvenous techniques. Thirty-three patients (6.7%) underwent surgical lead extraction, and 14 (2.8%) had retained leads or lead components. After a median follow-up of 352 [40 to 1,255] days after CIED extraction, 144 patients (29.0%) died. Repeat infection occurred in 47 patients (9.5%) with the median time from the extraction to repeat infection of 103 [45 to 214] days. In multivariable analysis, presence of a left ventricular assist device, younger age at extraction, and S. aureus infection were independent predictors of repeat infection. Additionally, chronic kidney disease, congestive heart failure, presence of septic emboli, S. aureus infection, and occurrence of major complications were independent predictors of increased mortality. CONCLUSIONS: Patients with S. aureus infection have a high risk of repeat infection and poor prognosis after CIED extraction. Repeat infection is also predicted by younger age and the presence of a left ventricular assist device, whereas mortality was predicted by congestive heart failure, chronic kidney disease, and septic emboli.

Staphylococcus bacteremia without evidence of cardiac implantable electronic device infection.

BACKGROUND: Staphylococcus bacteremia (SB) in the presence of a cardiac implantable electronic device (CIED) is frequently associated with CIED infection. In patients without clear CIED infection but SB, the role of empirical CIED removal is unclear. OBJECTIVE: The purpose of this study was to describe the natural history of SB in the setting of a CIED and the effect of CIED removal on mortality in patients with concurrent SB without evidence of CIED infection. METHODS: Three hundred sixty consecutive patients (mean age 61 ± 17 years; 255 (71%) men; 329 (92%) Staphylococcus aureus) with a CIED and concurrent SB were reviewed. RESULTS: At the initial presentation with SB, 178 patients had no evidence of CIED infection. Of these, 132 (74%) had another identified source of infection. Among the 178 patients without CIED infection, 18 (10%) had empirical CIED removal during the initial bacteremia. Among those who did not undergo CIED removal, SB subsequently relapsed in 19% and relapse rates were not different for those with or without another identifiable source at the initial presentation. Relapse was strongly associated with the duration of SB >1 day (odds ratio 9.99; 95% confidence interval 3.24-30.86). Despite the absence of CIED infection, 1-year mortality was 35% and empirical device removal during the initial presentation was associated with survival benefit (hazard ratio 0.28; 95% confidence interval 0.08-0.95). CONCLUSION: For patients with SB without evidence of CIED infection, relapse is predicted by the duration of bacteremia. Empirical CIED removal appears to be associated with a survival benefit, although there are likely clinical situations in which this could be deferred.

Candidemia in patients with cardiovascular implantable electronic devices.

PURPOSE: Current guidelines recommend complete extraction of cardiovascular implantable electronic devices (CIEDs) in the case of persistent or recurrent fungemia without other identifiable sources, though supporting evidence is lacking. We sought to evaluate the prognosis of patients with candidemia and CIEDs. METHODS: Twelve consecutive patients (54 ± 12 years, 8 male) with CIED and concurrent candidemia were reviewed. RESULTS: At the time of diagnosis with candidemia, seven patients were immunocompromised, six were on long-term antibacterial therapy, two were intravenous drug users, four were on chronic hemodialysis, and six had a central venous catheter. Four patients were confirmed as definite CIED infection as vegetation was visible on lead by echocardiogram. The other 8 patients were considered possible CIED infection with candidemia of unknown focus. All patients with visible vegetation underwent CIED removal without complications, and other patients were initially managed non-operatively. After 1 year of follow-up, 7 patients had died and at extended follow-up, all patients without lead removal died while 3 of 4 patients with lead extraction survived. Of note, 50% of deaths in the patients without lead removal were associated with fungal sepsis. CONCLUSIONS: Candida fungemia is associated with a high mortality. CIED removal should be an early consideration in these patients even if lead vegetations are not seen.

Detection of high-frequency artifact as a function of pulse generator algorithms and outer-insulation material.

BACKGROUND: A high rate of malfunction, predominantly intermittent high-frequency artifacts (HFAs), has been recently reported in Abbott Medical Tendril pacing leads. OBJECTIVE: To investigate the factors associated with the occurrence of HFAs on Tendril leads using a commonly used comparator lead for a control. METHODS: We reviewed institutional data for Medtronic CapSureFix 5076 and Abbott Medical Tendril pace-sense leads retrospectively. Recordings deemed to be due to electromagnetic interference and far-field oversensing were not included in the classification of HFAs. RESULTS: A total of 7673 leads were analyzed: 1628 Optim-insulated Tendril leads, 825 non-Optim Tendril leads, and 5220 CapSureFix 5076. HFAs were seen in 212 leads and were more frequently observed in Tendril compared to CapSureFix leads during a mean follow-up of 4.1 ± 3.6 years. Lower age at implant, defibrillator systems, atrial position, and connection to an Abbott Medical generator were associated with increased HFA. In multivariable analysis, only connection to Abbott Medical generators (odds ratio 7.686, P < .001) and age (odds ratio 0.988 per year, P = .016) were independently associated with HFAs on pace-sense leads. In an Abbott-generator-only analysis, Optim-insulated Tendril leads were more likely to display HFAs than non-Optim Tendril leads but not Medtronic CapSureFix 5076 leads. CONCLUSION: Abbott Medical pulse generators independently predict HFA in Tendril and CapSureFix 5076 leads, likely the result of displaying short or low-amplitude noise episodes that other devices do not record. When restricted to Abbott generators only, Optim-insulated Tendril leads show an increased incidence of HFAs when compared to non-Optim Tendril leads but not CapSureFix 5076 leads.

Transvenous Extraction and Removal of Pacing Leads Placed after Cardiac Transplantation.

There is an increasing prevalence of cardiac implantable electronic devices (CIEDs) due to expanding adoption and availability of these evidence-based therapies. With the increased prevalence of these life-saving devices, there has also been an increased demand for lead removal and lead extraction. Understanding the specific subgroups of patients at high risk for complications during and after lead extraction has become imperative to properly manage endovascular CIED leads. There have been multiple published studies describing clinical variables that predict adverse outcomes in CIED system extractions; however, the risk of complications in leads placed after cardiac transplantation has not specifically been addressed to date. We present four cases of transvenous extraction and removal of pacing leads placed after cardiac transplantation. There were no major complications related to extraction in these four cases; however, three of the four patients died within one year after the procedure. While the etiology of death in these cases seemed to be unrelated to the extraction procedure, the indications for extraction (infection in the setting of immunosuppression and calcineurin-associated ESRD and poor sensing/capture possibly secondary to chronic rejection and/or frequent right heart biopsies) likely contributed at least indirectly to the subsequent death.

Prevention and Treatment of Atrioesophageal Fistula Related to Catheter Ablation for Atrial Fibrillation.

Atrioesophageal fistula (AEF) is an uncommon but devastating complication of catheter ablation for atrial fibrillation. Even with appropriate recognition and treatment, mortality is greater than 30% in most studies. If AEF is suspected, it is essential to avoid endoscopy and to order immediate cross-sectional imaging. If the diagnosis is confirmed, a thoracic surgeon should be promptly notified and must assess the patient urgently. The prognosis for AEF is poor even if it is appropriately recognized and addressed, so prevention must be a high priority. Prevention of AEF should involve the use of low-risk and cost-effective measures during ablation, which may increase safety, efficacy, or both. These strategies may include conscious sedation (as opposed to general anesthesia), low-power ablation, low-flow irrigation, short-duration lesions, esophageal temperature measurement, esophageal deviation, and pharmacologic prophylaxis with proton pump inhibitors or histamine H2 receptor blockers. Multiple new technologies are now becoming available, which may further reduce esophageal injury. Proceduralists should be aware of the available techniques and equipment that may help to reduce the risk of AEF, while simultaneously considering the possibility of unintended consequences.