M. Maiani

Management of untreatable ventricular arrhythmias during pharmacologic challenges with sodium channel blockers for suspected Brugada syndrome

Pharmacologic challenge with sodium channel blockers is part of the diagnostic workout in patients with suspected Brugada syndrome. The test is overall considered safe but both ajmaline and flecainide detain well known pro-arrhythmic properties. Moreover, the treatment of patients with life-threatening arrhythmias during these diagnostic procedures is not well defined. Current consensus guidelines suggest to adopt cautious protocols interrupting the sodium channel blockers as soon as any ECG alteration appears. Nevertheless, the risk of life-threatening arrhythmias persists, even adopting a safe and cautious protocol and in absence of major arrhythmic risk factors. The authors revise the main published case studies of sodium channel blockers challenge in adults and in children, and summarize three cases of untreatable ventricular arrhythmias discussing their management. In particular, the role of advanced cardiopulmonary resuscitation with extra-corporeal membrane oxygenation is stressed as it can reveal to be the only reliable lifesaving facility in prolonged cardiac arrest.

From bench to bedside: Can the improvements in left ventricular assist device design mitigate adverse events and increase survival?

OBJECTIVE In vitro tests demonstrated that the new cone-bearing configuration of the Jarvik 2000 (Jarvik Heart Inc, New York, NY) left ventricular assist device exhibits better hydraulic efficiency than the previous pin-bearing design. We investigated the long-term outcomes of patients who received the Jarvik 2000 left ventricular assist device, depending on bearing design. METHODS A retrospective review of prospectively collected data from 18 centers included in the Italian Registry was performed. From May 2008 to September 2013, 99 patients with end-stage heart failure were enrolled. Patients were divided into 2 groups according to their Jarvik 2000 suspending mechanism: Group pin included patients with pin bearings (May 2008 to June 2010), and group cone included patients with newer cone bearings (July 2010 to September 2013). The 2 groups did not differ significantly in terms of baseline characteristics. RESULTS A total of 30 of 39 patients (group pin) and 46 of 60 patients (group cone) were discharged. During follow-up, 6 patients underwent transplantation, and in 1 patient the left ventricular assist device was explanted. The cumulative incidence competing risk of the entire cohort for noncardiovascular-related death was 28% (20%-40%); the cumulative incidence competing risk for cardiovascular-related death was 56% (42%-73%): 71% in group pin versus 26% in group cone (P = .034). The multivariate analyses confirmed that the pin-bearing design was a risk factor for cardiovascular death, along with Interagency Registry for Mechanically Assisted Circulatory Support class. Right ventricular failures and ischemic and hemorrhagic strokes were significantly higher in group pin. CONCLUSIONS Patients with the new pump configuration showed a better freedom from cardiovascular death and lower incidence of fatal stroke and right ventricular failure. Further studies are needed to prove the favorable impact of pump-enhanced fluid dynamics on long-term results.

Ceftolozane/tazobactam for the treatment of MDR Pseudomonas aeruginosa left ventricular assist device infection as a bridge to heart transplant

BackgroundCeftolozane/tazobactam (C/T) is a novel antibiotic with enhanced microbiological activity against multidrug-resistant (MDR) gram-negative bacteria, including MDR Pseudomonas aeruginosa.Case reportFive months after left ventricular assist device (LVAD) implantation, a 49-year old man developed fever and blood culture was positive for MDR P. aeruginosa, susceptible only to aminoglycosides, ciprofloxacin and colistin. A diagnosis of LVAD-related infection was made based on persistent bacteremia associated with moderate 18 F-fluorodeoxyglucose positron emission tomography/CT uptake in the left ventricular apex. Disk diffusion testing for C/T was performed (MIC 2 μg/mL) and intravenous antibiotic therapy with C/T and amikacin was started, with clinical and microbiological response. Initial conservative management with 6 weeks of systemic antibiotic therapy was attempted, but the patient relapsed one month after antibiotic discontinuation. Priority for transplantation was given and after 4 weeks of antibiotic therapy (C/T + amikacin), LVAD removal and heart transplant were performed, with no infection relapse.ConclusionsWe reported the first off-label use of C/T in the management of MDR P. aeruginosa LVAD infection as a bridge to heart transplant. C/T has shown potent anti-pseudomonal activity and good safety profile making this drug as a good candidate for suppressive strategy in intravascular device-associated bloodstream infections caused by MDR P. aeruginosa.

Heart Transplantation in Patients Supported by ECMO: Is the APACHE IV Score a Predictor of Survival?: Thoughts and Progress

Bridge to heart transplantation (HTx) with ECMO is associated with poor outcome, but patient status, according to different levels of multiorgan compromise, is generally not considered. The aim of this study was to analyze the prognostic value of acute physiology, age, and chronic health evaluation IV (APACHE IV) score in this setting. Thirty-two patients underwent HTx bridged with ECMO at our institution between 2005 and 2017; they were divided into two groups, according to a cutoff value of APACHE IV score obtained by Receiver operating characteristic curve analysis for 30-day mortality. Kaplan-Meyer survival curves were plotted, and compared through the log-Rank test. Cox regression model was used to estimate which factors were associated with overall survival. The 30-day mortality prediction of the APACHE IV score showed an AUC of 0.98 [95% C.I. 0.84-0.99], with a cutoff value corresponding to a score value of 47 (specificity of 84.6% and sensitivity of 100%) in order to discriminate between a group with low probability (Group A, patients with an APACHE IV score <47), and a group with high probability (Group B, patients with an APACHE IV score ≥47) of 30-day mortality. Median follow up was 26.9 months (range: 0.03-143.8). On overall, patients bridged with ECMO showed a high early mortality (18.7% <30 days, n = 6). All deaths occurred in Group B, where 30-day mortality was 60%. Survival probability among Group B patients was 26.6% at both 1 and 5 years. Conversely, in Group A no early mortality was reported, and the estimated survival was 89.7% at 1 year and 81.5% at 5 years, respectively. Mortality correlated at univariate analysis with recipient age, APACHE IV score and female sex, while the multivariate Cox regression analysis showed that only an APACHE IV score (HR 1.23 [1.08-1.39, 95% C.I.]) and female sex (HR 6.68 [1.42-31.43, 95% C.I.]) had an adverse impact on survival. This study shows that the APACHE IV score could be considered a powerful predictor of survival in patients bridged by ECMO to HTx, and can account for a better selection of patients on ECMO support at time of listing.