K.P. Mody

Continuous-flow left ventricular assist devices and usefulness of a standardized strategy to reduce drive-line infections

BACKGROUND Drive-line infection (DLI) is a common complication of left ventricular assist device (LVAD) support, leading to significant morbidity that jeopardizes the benefits of these devices. It has been reported that DLI incidence is related to drive-line dressing strategies. The aim of this study was to determine whether implementation of a standardized drive-line care kit would reduce the incidence of DLIs. METHODS DLI data were collected prospectively on all LVAD patients implanted between 2009 and 2013 at Columbia University Medical Center. Drive-line care was altered on June 1, 2011, from a dry sterile dressing without a standard anchoring device to a standardized kit, which included silver gauze dressing and a standard anchoring device. The silver dressing was used until the wound incorporated, with a minimum of 1 month. RESULTS During the study period, 107 patients were implanted with LVADs before implementation of a standardized kit (Group A) and 159 thereafter (Group B). Median follow-up time (censoring at June 2011) for Group A was 8.73 (IQR 3.51 to 17.47) months and 11.65 (IQR 6.66 to 35.20) months for Group B (p = 0.17). DLI event rate improved from 0.18 to 0.07 event per patient-year, corresponding to a relative risk reduction of 62.5%. In addition, the 1-year freedom from infection was significantly increased in Group B (92.46%) compared with Group A (81.94%) (log rank = 0.036). CONCLUSION The use of a standardized kit, including silver dressing and a standard anchoring device, leads to decrease in DLI with an absolute risk reduction of 11%. Routine use of these dressing techniques is warranted based on our findings, and may lead to reduction of complications related to infections.

Device exchange in HeartMate II recipients: long-term outcomes and risk of thrombosis recurrence.

Successful long-term use of the HeartMate II (HM II) left ventricular assist device has become commonplace but may be complicated by mechanical failure, infection, or thrombosis necessitating device exchange (DE). A subcostal approach to device exchange with motor exchange only is less traumatic, but long-term outcomes have not been reported. A retrospective chart review of all patients who required HM II to HM II device exchange at our institution was conducted. Of the 232 HM II patients implanted between January 2008 and July 2013, 28 required 36 device exchanges during a follow-up of 33.72 ± 17.25 months. The Kaplan–Meier 1 year survival was 63% for sternotomy exchanges and 100% for subcostal exchanges. Twenty-one exchanges were performed for initial or recurring device thrombosis. Although there was no difference in the risk of subsequent thrombosis after subcostal versus sternotomy exchange, the overall risk of recurring device thrombosis after device exchange for the same was high (31%). HM II device exchange via the subcostal approach has excellent short- and long-term outcomes. Device exchange performed for thrombosis is associated with a high recurrence risk irrespective of surgical approach

Catheter ablation for ventricular tachyarrhythmias in patients supported by continuous-flow left ventricular assist devices

Ventricular arrhythmias (VAs) are common after implantation of a left ventricular assist device (LVAD) and in a subset of patients may be refractory to medication. Morbidity from VA in this population includes right ventricular failure (RVF). We sought to evaluate the efficacy of catheter ablation for VA in patients with LVAD. A retrospective analysis of patients supported by continuous-flow LVAD referred for catheter ablation of ventricular tachycardia (VT) between 2008 and the present was performed. Seven patients were referred for VT ablation an average of 236 ± 292 days after LVAD implantation. Three patients (42.9%) developed RVF in the setting of intractable arrhythmias. A transfemoral approach was used for six patients (85.7%) and an epicardial for one patient (14.3%). The clinical VT was inducible and successfully ablated in six patients (85.7%). The location of these arrhythmias was apical in three cases (42.9%). A total of 13 VTs were ablated in seven patients. Although the majority had reduction in VA frequency, recurrent VAs were observed in six patients (85.7%). One patient (14.3%) experienced a bleeding complication after the procedure. For patients with a high VA burden after LVAD implantation, VT ablation is safe and feasible, but VA frequently recurs.

Advanced cardiovascular life support algorithm for the management of the hospitalized unresponsive patient on continuous flow left ventricular assist device support outside the intensive care unit

Over the past decade, continuous flow left ventricular assist devices (CF-LVADs) have become the mainstay of therapy for end stage heart failure. While the number of patients on support is exponentially growing, at present there are no American Heart Association or European Society of Cardiology Advanced Cardiovascular Life Support guidelines for the management of this unique patient population. We propose an algorithm for the hospitalized unresponsive CF-LVAD patient outside of the intensive care unit setting. Key elements of this algorithm are: creation of a dedicated LVAD code pager and LVAD code team; early assessment and correction of LVAD malfunction; early determination of blood flow using Doppler technique in carotid and femoral arteries; prompt administration of external chest compressions in the absence of Doppler flow; bedside veno-arterial extracorporeal membranous oxygenation support if no response to resuscitation measures; and early consideration for stroke.

Correlation Between Home INR and Core Laboratory INR in Patients Supported with Continuous-Flow Left Ventricular Assist Devices.

It has been well established that patient self-testing (PST) of international normalized ratio (INR) using home monitoring devices increases the average therapeutic time and patient satisfaction. Long-term anticoagulation therapy with warfarin is used in patients with continuous-flow left ventricular assist device (CF-LVAD) to minimize the occurrence of thromboembolic events; however, PST devices have never been tested in patients with CF-LVADs. The purpose of this study was to determine the reliability of the PST device Alere INRatio 2 in patients supported with CF-LVADs. A correlation study was performed in 50 patients with CF-LVAD who were on stable warfarin therapy for a minimum of 3 weeks. Simultaneous INR values were determined from capillary whole blood samples using the Alere PST device and venous blood samples processed in the core laboratory at Columbia University Medical Center. There was a moderate correlation between the venous and the capillary INR values with a correlation coefficient of 0.83. The median difference between the methods was 0.39, with 44 of 50 patients recording higher INRs with Alere. Results remained unchanged after adjusting for use of amiodarone, abnormal hematocrit and liver enzymes, creatinine, and thyroid-stimulating hormone. Point of care testing with Alere correlates moderately well but consistently overestimates INR when compared with conventional laboratory testing in patients with CF-LVAD.

Longitudinal Case Based Presentations in HCM

A significant volume of data has been published over the past few decades regarding HCM. In 2011 the ACCF/AHA issued guidelines for management and diagnosis, and in 2014 the ESC guidelines were formalized. Nonetheless, the acute and chronic management of HCM is highly nuanced, based on collective experience of many patients. To elucidate the subtleties of management, eight carefully selected cases attempt to depict the medical decision-making process at various stages of illness. Case 1 is a middle-aged male with refractory NYHA Class III symptoms who eventually improved after surgical septal reduction. Case 2 is a young female with history of sudden death and refractory symptoms who required invasive therapy, and a successful alcohol septal ablation was performed due to strong patient preference. Case 3 is a young female without significant outflow tract obstruction but with advanced diastolic heart failure who eventually required a heart transplant. Case 4 depicts severe obstructive HCM in a female with advanced age who after an extended course of medical therapy eventually improved post-alcohol septal ablation. Case 5 is a relatively young female post ICD for SCD with ICD lead complications and atrial fibrillation but well managed medically. Case 6 is a middle-aged male with severe obstructive HCM who required invasive therapy eventually and preferred alcohol septal ablation to surgery. Case 7 is a patient with obstructive HCM referred for alcohol septal ablation who was subsequently determined to have a subaortic membrane and ultimately required surgical treatment. Case 8 is a 40-year-old patient who underwent surgical myectomy but became symptomatic again 3 years after her surgery and eventually underwent alcohol septal ablation. As will become clear, appropriate care of HCM patients requires an individualized and comprehensive approach keeping in view their specific and oftentimes changing presentation, currently available data, and guidelines, all within the confines of a dedicated HCM center.

A Cold Taken to Heart

Information about a real patient is presented in stages (boldface type) to expert clinicians (Dr Uriel and Dr Jorde), who respond to the information, sharing their reasoning with the reader (regular type). A discussion by the authors follows. A 35-year-old woman with no past medical history presented to her local emergency room with 2 days of fevers, chills, and myalgias. She was febrile with a temperature of 102°F, blood pressure of 95/60 (72) mm Hg, heart rate of 110 bpm, respiratory rate of 20 breaths per minute, and an oxygen saturation of 100% on 2 L oxygen. The physical examination was notable for cool extremities, clear lungs, and tachycardic heart sounds with no s3, s4, or friction rub. The patient decompensated quickly and developed hypotension, requiring rapid uptitration of norepinephrine to 12 μg·kg − 1 · min − 1 . The ECG ( Figure 1) showed sinus tachycardia with ST-segment elevation in the inferolateral leads. Laboratory results were notable for cardiac troponin of 3.89 ng/mL (normal range, 0–0.08 ng/mL), venous lactate of 3.5 mmol/L (normal range, 0.50–2.20 mmol/L), white blood cell count of 17.0×109 per 1 L (normal range, 3.5–9.1×109 per 1 L), and hemoglobin of 12.4 g/dL (normal range, 13.3–16.2 g/dL) with preserved hepatic and renal function. Figure 1. ECG from the emergency room demonstrating sinus tachycardia, subtle ST-segment elevations in the inferolateral leads Dr Uriel: Interpretation of the clinical course so far: A young woman with no medical history presents with an infectious syndrome and rapidly deteriorates. At this point, one must consider the different processes that would result in such a dramatic clinical picture. It is important to begin to rapidly rule out life-threatening processes and to perform the appropriate clinical testing in a manner that will not delay treatment. Given the increasing hypoxia, an assessment of the lung parenchyma …

LATE GADOLINIUM ENHANCEMENT PREDICTS CARDIAC EVENTS IN NON-ISCHEMIC CARDIOMYOPATHY: A META-ANALYSIS

Presence of late gadolinium enhancement (LGE) on cardiac MRI (CMR) in non-ischemic cardiomyopathy (NICM) may predict adverse cardiac events. Current published studies are limited by sample size and varying outcomes. We sought to better evaluate the utility of LGE in NICM with a meta-analysis. A