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.

Outcomes in patients with cardiac amyloidosis and implantable cardioverter-defibrillator.

AIMS: Cardiac amyloidosis (CA) is associated with increased mortality due to arrhythmias, heart failure, and electromechanical dissociation. However, the role of an implantable cardioverter-defibrillator (ICD) remains unclear. We conducted case-control study to assess survival in CA patients with and without a primary prevention ICD and compared outcomes to an age, sex, and device implant year-matched non-CA group with primary prevention ICD. METHODS AND RESULTS: There were 91 subjects with CA [mean age= 71.2 ± 10.2, female 22.0%, 49 AL with Mayo Stage 2.9 ± 1.0, 41 transthyretin amyloidosis (ATTR), 1 other] followed by Vanderbilt Amyloidosis centre. Patients with ICD (n = 23) were compared with those without (n = 68) and a non-amyloid group with ICD (n = 46). All subjects with ICD had implantation for primary prevention. Mean left ventricular ejection fraction was 36.2% ± 14.4% in CA with ICD, 41.0% ± 10.6% in CA without ICD, and 33.5% ± 14.4% in non-CA patients. Over 3.5 ± 3.1 years, 6 (26.1%) CA, and 12 (26.1%) non-CA subjects received ICD therapies (P = 0.71). Patients with CA had a significantly higher mortality (43.9% vs. 17.4%, P = 0.002) compared with the non-CA group. Mean time from device implantation to death was 21.8 months in AL and 22.8 months in ATTR patients. There was no significant difference in mortality between CA patients who did and did not receive an ICD (39.0% vs. 46.0%, P = 0.59). CONCLUSIONS: Despite comparable event rates patients with CA had a significantly higher mortality and ICDs were not associated with longer survival. With the emergence of effective therapy for AL amyloidosis, further study of ICD is needed in this group.

Clinical predictors of acute hyponatremia following LARIAT ligation of the left atrial appendage.

INTRODUCTION: Hyponatremia commonly follows percutaneous exclusion of the left atrial appendage (LAA) with the LARIAT suture delivery device. The aim of this study was to evaluate for clinical predictors hyponatremia following ligation of the appendage with the LARIAT device. METHODS AND RESULTS: A retrospective analysis was conducted on 61 consecutive patients (average age 69.7 ± 9.8 years, 55.7% male) who underwent successful appendage ligation with the LARIAT device. Acute hyponatremia (AH) was defined as a drop in serum sodium (Na) by greater than or equal to 4 mmol/L within 48 hours of ligation while exaggerated acute hyponatremia (EAH) was defined as a drop greater than or equal to 10 mmol/L. Among all patients, there was a significant decrease in [Na] at 24 hours (3.26 ± 2.77 mmol/L) and 48 hours (4.98 ± 3.74 mmol/L). Thirty-two patients (52.4%) had AH while six patients (9.8%) experienced EAH. A body mass index (BMI) of less than 28.4 kg/m2 was associated with AH (P = .037) while a BMI < 25 kg/m2 was associated with EAH (P = .021). A linear regression analysis comparing the maximum sodium decrease to the indexed left atrial (LA) diameter found that for every 1 cm/m2 increase in indexed LA diameter, there was a 2.5 mEq/L decrease in serum sodium (P = .04). CONCLUSIONS: Hyponatremia frequently occurs following LAA ligation with the LARIAT device. A low BMI < 25 kg/m2 is associated with a drop in serum sodium of greater than 10 mmol/L while increasing indexed LA diameter predicts any AH. AH is also associated with a significantly lower systolic blood pressure 48 to 72 hours post LAA exclusion with the LARIAT device.

Potential impact of cardiology phone-consultation for patients risk-stratified by the HEART pathway.

Objective: Bedside consultation by cardiologists may facilitate safe discharge of selected patients from the emergency department (ED) even when admission is recommended by the History, Electrocardiogram, Age, Risk factors, Troponin (HEART) pathway. If bedside evaluation is unavailable, phone consultation between emergency physicians and cardiologists would be most impactful if the resultant disposition is discordant with the HEART pathway. We therefore evaluate discordance between actual disposition and that suggested by the HEART pathway in patients presenting to the ED with chest pain for whom cardiology consultation occurred exclusively by phone and to assess the impact of phone-consultation on disposition. Methods: We performed a single-center, retrospective study of adults presenting to the ED with chest pain whose emergency physician had a phone consultation with a cardiologist. Actual disposition was abstracted from the medical record. HEART pathway category (low-risk, discharge; high-risk, admit) was derived from ED documentation. For discharged patients, major adverse cardiac events were assessed at 30 days by chart review and phone follow-up. Results: For the 170 patients that had cardiologist phone consultation, discordance between actual disposition and the HEART pathway was 17%. The HEART pathway recommended admission for nearly 80% of discharged patients. Following cardiologist phone-consultation, 10% of high-risk patients were discharged, with the majority having undergone a functional study recommended by the cardiologist. At 30 days, discharged patients had experienced no episodes of major adverse cardiac events or rehospitalization for cardiac reasons. Conclusion: For patients presenting to the ED with chest pain, cardiology phone-consultation has the potential to safely impact disposition, primarily by facilitating functional testing in high-risk individuals.

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.