Outcomes of Standard Permanent Active Fixation Leads for Temporary Pacing.

OBJECTIVES: This study investigated the performance of Temporary Pacing via an Externalized Active-Fixation (TPEAF) lead. BACKGROUND: The incidence of cardiac implantable electronic device infections is increasing, which necessitates the need for transvenous lead extraction (TLE). Pacemaker-dependent patients require temporary pacing during the guideline-recommended waiting period before reimplantation. Data regarding safety and efficacy of TPEAF leads are very limited. METHODS: We evaluated patients implanted with TPEAF leads post-TLE at our center between April 2004 and December 2017. RESULTS: TPEAF leads were placed in 158 patients. The mean age was 74 ± 11 years. The median duration of the temporary lead was 6 days (range 1 to 29). There were 4 procedural complications (2.5% incidence): 1 patient had cardiac arrest from hyperkalemia, 2 developed cardiac tamponade, and 1 had profuse bleeding from the entry point of the leads. There were 13 complications post-implantation (8.2% incidence): 8 lead dislodgments, 1 elevated pacing threshold, 2 vegetations on the temporary lead, 1 pneumothorax, and 1 loss of capture due to the generator "safety switch." All dislodgements occurred within 24 h, except 1 on day 3. Sixteen patients died during the hospital stay: 10 due to septic shock, 2 due to hyperkalemic cardiac arrest, 3 due to ventricular tachycardia, and 1 due to a massive cerebrovascular accident. CONCLUSIONS: The use of TPEAF leads is safe and efficacious in pacemaker-dependent patients post-TLE. Dislodgement can occur within the first 24 h. The presence of persistent fever and positive blood cultures should raise concern for vegetation on the temporary lead.

Device Management in Heart Failure.

PURPOSE OF REVIEW: Medical devices have become an integral part of comprehensive heart failure management. Not all heart failure patients, however, accrue benefit from every new device, and even with extensive practice guidelines, this remains an evolving field. RECENT FINDINGS: The addition of implantable devices, like internal cardioverter defibrillators (ICDs), and novel pacing technologies, including cardiac resynchronization therapy (CRT), have helped to compliment goal-directed medical therapy and positively impact prognosis in multiple high-quality clinical trials. This review attempts to summarize the rapidly evolving literature with respect to existing device guidelines for routine implantable devices as well as some available and future technologies that are not yet a part of routine guidelines. ICD, CRT, and other implantable devices continue to save lives, decrease hospitalizations, and evolve the management of patients with heart failure beyond the capabilities of optimal guideline-directed medical therapy alone.

Outcomes of subcutaneous implantable cardioverter-defibrillator implantation in patients on hemodialysis.

BACKGROUND: Subcutaneous implantable cardioverter-defibrillator (S-ICD) provides potential benefits in patients on hemodialysis (HD) by reducing the risk of blood stream infection and preserving vascular access sites. We evaluated the safety and efficacy of S-ICD in patients with end-stage renal disease (ESRD) on HD. METHODS: All consecutive patients implanted with S-ICD between October 2012 and April 2015 at our high-volume center were included in this retrospective, single-center study. Baseline demographics, procedural details, and short- as well as long-term outcomes were compared between patients on HD and not on HD. RESULTS: A total of 86 S-ICDs were implanted at our institution during the study period. Eighteen (21%) patients were on HD at the time of implant. HD patients were more likely to be implanted for secondary prevention. There was no statistically significant difference in procedural complications between the two groups. HD patients had a longer duration hospital stay after implant (3.6 ± 5.14 vs. 1.69 ± 2.29 days, p = 0.021). During a mean follow-up of 205 ± 208 days in the HD cohort and 242 ± 238 days in the non-HD cohort (p = 0.268), there was no device or blood stream infection in the HD group, compared with five device infections in the non-HD group. The incidence of inappropriate shocks was similar in both groups. All appropriate shocks were successful in terminating ventricular tachyarrhythmias in both groups. Patients on hemodialysis had worse inpatient as well as long-term mortality after S-ICD implant, compared with non-HD patients. CONCLUSIONS: Our study demonstrates the safety and efficacy of S-ICD in patients on HD. Despite representing a sicker patient population, HD patients implanted with S-ICD had similar procedural outcomes and inappropriate shocks. There was no device or blood stream-related infection in HD patients. All appropriate shocks for ventricular arrhythmias in HD patients were successful.

Aggregatibacter aphrophilus pacemaker endocarditis: a case report.

BACKGROUND: Aggregatibacter bacteria are a rare cause of endocarditis in adults. They are part of a group of organisms known as HACEK--Haemophilus, Aggregatibacter, Cardiobacter, Eikenella, and Kingella. Among these organisms, several Haemophilus species have been reclassified under the genus Aggregatibacter. Very few cases of Aggregatibacter endocarditis in patients with pacemaker devices have been reported. CASE PRESENTATION: We present here what we believe to be the first case of Aggregatibacter aphrophilus pacemaker endocarditis. A 62-year-old African American male with a medical history significant for dual-chamber pacemaker placement in 1996 for complete heart block with subsequent lead manipulation in 2007, presented to his primary care doctor with fever, chills, night sweats, fatigue, and ten-pound weight loss over a four-month period. Physical examination revealed a new murmur and jugular venous distension which prompted initiation of antibiotics for suspicion of endocarditis. Both sets of initial blood cultures were positive for A. aphrophilus. Transesophageal echocardiogram revealed vegetations on the tricuspid valve and the right ventricular pacemaker lead (Figure 1). This case highlights the importance of identifying rare causes of endocarditis and recognizing that treatment may not differ from the standard treatment for typical presentations. The patient received intravenous ceftriaxone for his endocarditis for a total of six weeks. Upon device removal, temporary jugular venous pacing wires were placed. After two weeks of antibiotic treatment and no clinical deterioration, a new permanent pacemaker was placed and the patient was discharged home. CONCLUSIONS: This is the first case of A. aphrophilus endocarditis in a patient with a permanent pacemaker. Our patient had no obvious risk factors other than poor dentition and a history of repeated pacemaker lead manipulation. This suggests that valvulopathies secondary to repeated lead manipulation can be clinically significant factors in morbidity and mortality in this patient population.

Protection from outpatient sudden cardiac death following ICD removal using a wearable cardioverter defibrillator.

BACKGROUND: An implantable cardioverter defibrillator (ICD) is effective in preventing sudden cardiac death (SCD). Once an ICD is removed and reimplantation is not feasible, a wearable cardioverter defibrillator (WCD) may be an alternative option. We determined the effectiveness of WCD for SCD prevention in patients who were discharged after ICD removal. METHODS: A retrospective study was conducted on all WCD (LifeVest, ZOLL, Pittsburgh, PA, USA) patients who underwent ICD removal due to cardiac device infections (CDIs) at two referral centers between January 1, 2005 and December 31, 2009. Clinical characteristics, device information, and WCD data were analyzed. Sudden cardiac arrest was defined as all sustained ventricular tachycardia (VT) and ventricular fibrillation occurring within a single 24-hour period. RESULTS: Ninety-seven patients (mean age 62.8 ± 13.3, male 80.4%) were included in the study. The median duration of antibiotic use was 14.7 days (interquartile range [IQR] 10-30). The median daily WCD use was 20 hours/day and the median length of use was 21 days (IQR 5-47). A total of three patients were shocked by WCD. Two patients had four episodes of sustained VT, successfully terminated by the WCD. A third patient experienced two inappropriate treatments due to oversensitivity of the signal artifact. Three patients experienced sudden death outside the hospital while not wearing the device. Five patients died while hospitalized. CONCLUSION: WCD can prevent SCD, until ICD reimplantation is feasible in patients who underwent device removals for CDI. However, patient compliance is essential for the effective use of this device.

Arrhythmias and heart failure.

Atrial fibrillation and ventricular tachyarrhythmias are frequently seen in patients with heart failure, and complicate the management of such patients. Both types of arrhythmia lead to increased morbidity and mortality, and often prove to be challenging issues to manage. The many randomized studies that have been performed in patients with these conditions and concomitant heart failure have helped in designing optimal treatment strategies.

Clinical utility of intravascular ultrasound in the assessment of coronary allograft vasculopathy: a review.

Coronary artery vasculopathy (CAV) is one of the major factors that limit the long-term survival of heart transplant recipients. It is difficult to diagnose CAV, especially in the early stages. Traditional coronary angiography has been used for the diagnosis of CAV, but this method has limitations. Current literature suggests that intravascular ultrasound (IVUS) is a safe imaging technique that is beneficial for the early diagnosis of CAV; in comparison, IVUS with virtual histology (IVUS-VH) is an even more promising diagnostic utility. Despite its advantages, IVUS is currently not routinely utilized as the primary diagnostic modality for CAV in heart transplant recipients. In this review, we evaluate and summarize the clinical utility of IVUS in the early diagnosis of CAV, including its utility for assessing vessel remodeling, plaque composition, and prognostic value; morphometric analysis; and guiding therapy. After reviewing the relevant published literature, it is our recommendation that the use of IVUS be considered in all post-transplant CAV screening.

Renal dysfunction in heart failure patients: what is the evidence?

Congestive heart failure (CHF) is an increasingly common medical condition and the fastest growing cardiovascular diagnosis in North America. Over one-third of patients with heart failure also have renal insufficiency. It has been shown that renal insufficiency confers worsened outcomes to patients with heart failure. However, a majority of the larger and therapy-defining heart failure medication and device trials exclude patients with advanced renal dysfunction. These studies also infrequently perform subgroup analyses based on the degree of renal dysfunction. The lack of information on heart failure patients who have renal insufficiency likely contributes to their being prescribed mortality and morbidity reducing medications and receiving diagnostic and therapeutic procedures at lower rates than heart failure patients with normal renal function. Inclusion of patients with renal insufficiency in heart failure studies and published guidelines for medication, device, and interventional therapies would likely improve patient outcomes.

Recognition of apertures in overhead transparent barriers by leopard frogs.

Anurans have independent systems for detecting moving stimuli and stationary opaque objects. We have discovered that leopard frogs will also orient to, and spontaneously and accurately jump through, circular apertures in overhead transparent covers. When given a choice between one large aperture of 3.8 cm diameter, and three apertures of smaller but equal diameter (2.5 cm diameter, 1.9 cm diameter, or 1.3 cm diameter) they choose the larger diameter aperture at a frequency (64, 87 and 97%, respectively) that is statistically greater than chance. In only 1 of 255 attempts was there a jump to the overhead cover that was not directed at an aperture. Atectal frogs are still able to detect and jump accurately through transparent apertures. Frogs cannot distinguish between two apertures of equal diameter if one aperture is covered with clear plastic with high light transmissibility (92% of transmissibility of air). However, if the plastic covering of the aperture has a residue which reduces light through the cover from 92 to 87% of the transmissibility of air, frogs will jump to the uncovered aperture at a frequency that is statistically greater than chance. Our results show that leopard frogs have an extremely well developed ability to detect overhead apertures just as they can vertical obstacles. They are able to jump towards such openings with a small margin of error independent of the tectal visual system.