Filio Billia

Clinical Differences Between Continuous Flow Ventricular Assist Devices: A Comparison Between HeartMate II and HeartWare HVAD

The HeartWare ventricular assist device (HVAD) is a new generation centrifugal flow VAD recently introduced in Canada. The objective of this study was to compare the HVAD device to the HeartMate II (HMII) axial flow device. Very few studies have compared clinical outcomes between newer generation VADs.

Parkinson-susceptibility gene DJ-1/PARK7 protects the murine heart from oxidative damage in vivo

Oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) and the ability of an organism to eliminate these toxic intermediates. Although the Parkinson-susceptibility gene, Parkinson protein 7/DJ-1 (DJ-1), has been linked to the regulation of oxidative stress, the exact mechanism by which this occurs and its in vivo relevance have remained elusive. In the heart, oxidative stress is a major contributor to the development of heart failure (HF). Therefore, we hypothesized that DJ-1 inhibits the pathological consequences of ROS production in the heart, the organ with the highest oxidative burden. We report that DJ-1 is highly expressed in normal heart tissue but is markedly reduced in end-stage human HF. DJ-1-deficient mice subjected to oxidative stress by transaortic banding exhibited exaggerated cardiac hypertrophy and susceptibility to developing HF. This was accompanied by a Trp53 (p53)-dependent decrease in capillary density, an excessive oxidation of DNA, and increased cardiomyocyte apoptosis, key events in the development of HF. Impaired mitochondrial biogenesis and progressive respiratory chain deficiency were also evident in cardiomyocytes lacking DJ-1. Our results provide compelling in vivo evidence that DJ-1 is a unique and nonredundant antioxidant that functions independent of other antioxidative pathways in the cellular defense against ROS.

Echocardiography for adult patients supported with extracorporeal membrane oxygenation

Venoarterial (VA) and venovenous (VV) extracorporeal membrane oxygenation (ECMO) support is increasingly being used in recent years in the adult population. Owing to the underlying disease precipitating severe respiratory or cardiac failure, echocardiography plays an important role in the management of these patients. Nevertheless, there are currently no guidelines on the use of echocardiography in the setting of ECMO support. This review describes the current state of application of echocardiography for patients supported with both VA and VV ECMO.

Right Ventricular Function and Prognosis in Stable Heart Failure Patients

BACKGROUND Right ventricular ejection fraction (RVEF) is a mortality predictor in heart failure (HF) patients. There are controversial results regarding the influence of RVEF on other important prognostic variables. The purpose of this study was to investigate the effect of RVEF on exercise parameters obtained during cardiopulmonary exercise testing (CPET), creatinine and B-type natriuretic peptide (BNP) levels, and a composite outcome of death, heart transplantation, or ventricular assist device implantation in ambulatory HF patients. METHODS AND RESULTS This retrospective cohort study included 246 ambulatory HF patients with CPET and RVEF evaluated with the use of first-pass radionuclide angiography. We analyzed the impact of RVEF on other prognostic factors with the use of multivariable linear regression. The mean age was 49 ± 12 years. The mean peak VO2 was 16.4 ± 5.7 mL kg(-1) min(-1), mean peak VE/VCO2 34.1 ± 9.1, mean creatinine 1.17 ± 0.40 mg/dL, and median BNP 158 pg/mL (interquartile range 374 pg/mL). The mean left ventricular ejection fraction was 35 ± 12% and the mean RVEF 38 ± 10%. For every 10% decrease in RVEF, peak VO2 decreased 0.97 mL kg(-1) min(-1) (P < .05), creatinine increased 0.12 mg/dL (P < .01), and log BNP increased 0.26 (P < .05). CONCLUSIONS We found an independent association between RVEF and prognostic markers in HF patients. Worsening RV function may exert its negative effect on prognosis through increasing congestion (elevated BNP), affecting renal blood flow (increased creatinine) and limiting left ventricular preload, thereby reducing exercise tolerance.

High-risk cardiac surgery as an alternative to transplant or mechanical support in patients with end-stage heart failure

Objective Although the results of cardiac surgery in patients with poor left ventricular function have been widely published, the outcomes in patients with end‐stage heart failure who meet criteria for advanced therapies are not well investigated. As access to transplantation and ventricular assist device therapy remains limited, we explored the possibility of conventional surgery as an alternative option for highly selected patients with end‐stage heart failure. Methods We identified patients with left ventricular ejection fraction <20% and VO2 max <14 mL/min/m2, who were initially referred for advanced therapies but were instead offered a conventional procedure from 2002 to 2012. We examined the short‐ and midterm outcomes and compared survival with that after our advanced therapies in the same era. Results A total of 133 patients were identified; 68 were deemed to be transplant‐eligible, whereas 65 were transplant‐ineligible. Seventy‐nine percent were in New York Heart Association class III/IV. In‐hospital mortality was 12%. Actuarial survival at 5 and 10 years was 72% ± 4% and 39% ± 8%, respectively. Nonischemic etiology was identified as a predictor of late mortality. In the propensity‐adjusted model, our transplant‐eligible patients had comparable long‐term survival to our transplantation patients (HR 1.48 [95% confidence interval, 0.66‐3.2], P = .34), whereas the survival in our transplant‐ineligible subset was comparable to the survival after our left ventricular assist device therapy (HR 0.49 [95% confidence interval, 0.16‐1.50], P = .21). Conclusions Despite high perioperative risk, the midterm survival after conventional surgery in patients eligible for advanced therapies seems to be acceptable and may be an alternative option for highly selected patients with end‐stage heart failure.

Phenotype, management and predictors of outcome in a large cohort of adult congenital heart disease patients with heart failure

OBJECTIVE Although heart failure (HF) is the leading cause of premature death in adult congenital heart disease (ACHD), little population-specific data exist. This study reports early experience from a dedicated, sub-specialty adult congenital heart disease-heart failure (ACHD-HF) clinic, aiming to identify risk factors for adverse outcome. METHODS Between 2012 and 2015, 126 patients (57% male) attended the ACHD-HF clinic. Baseline and follow-up data were analysed and compared across 4 anatomical/physiological subgroups: cyanotic ACHD, Fontan circulation (1V), biventricular circulation with a subaortic right ventricle (2V-RV) and biventricular circulation with a subaortic left ventricle (2V-LV). Predictors of the composite primary outcome: death, transplant or ventricular assist device (VAD) were identified using multivariable Cox proportional hazard models. RESULTS Mean age at first visit was 38±13years. Patients were grouped as follows: cyanotic ACHD 10%, 1V 24%, 2V-RV 29% and 2V-LV 37%. During a median follow-up of 1.7 (IQR 0.8-2.9) years, 38 patients (30%) reached the primary outcome. Event-free survival was 89%, 78% and 63% at 1, 2 and 3years. Forty (31.7%) patients experienced 69 HF hospitalisations. Between-group differences were noted for systolic function, valvular regurgitation, pacing prevalence and invasive hemodynamics. Multivariable analysis revealed 2V-RV subgroup (p=0.001), NYHA class (p=0.002) B-type natriuretic peptide >164pg/ml (p=0.003) and sodium <136mmol/L (p=0.036) as independently associated with death, transplant or VAD. CONCLUSIONS Our young ACHD-HF patients experienced high adverse event rates during a short period of follow-up. The prognostic markers identified will aid clinicians to stratify short-term risk and thereby guide advanced HF management decisions in ACHD.

Percutaneous left atrial decompression in adults with refractory cardiogenic shock supported with veno-arterial extracorporeal membrane oxygenation

Left ventricular (LV) distention, a recognized complication in patients supported with veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) for refractory cardiogenic shock, can lead to pulmonary edema, increased myocardial oxygen consumption, and LV thrombus formation. Atrial septostomy was examined as a management strategy for LV distension.

Patient perceptions of implantable cardioverter-defibrillator deactivation discussions: A qualitative study.

Background: There is a class I recommendation for implantable cardioverter-defibrillator deactivation discussions to occur between physicians and heart failure patients. Few studies have reported the patient’s perspective on the timing of implantable cardioverter-defibrillator deactivation discussions. Aim: To determine patient awareness, preferences and timing of implantable cardioverter-defibrillator deactivation discussions. Design: Grounded theory was used to collect and analyze interview data from 25 heart failure patients with an implantable cardioverter-defibrillator. Setting and participants: Patients with an implantable cardioverter-defibrillator, from the Heart Function Clinic at University Health Network (Toronto, Canada). Results: The sample (n = 25) was predominately male (76%) with an average age of 62 years. Patients identified three stages where they felt implantable cardioverter-defibrillator deactivation should be discussed: (1) prior to implantation, (2) with any significant deterioration but while they were of sound mind to engage in and communicate their preferences and (3) at end of life, where patients wished further review of their previously established preferences and decisions about implantable cardioverter-defibrillator deactivation. Most patients (n = 17, 68%) said they would consider deactivation, six (24%) were undecided and two (8%) were adamant they would never turn it off. Conclusion: The patient preferences identified in this study support the need to include information on implantable cardioverter-defibrillator deactivation at implant, with change in clinical status and within broader discussions about end-of-life treatment preferences. Using this process to help patients determine and communicate their implantable cardioverter-defibrillator deactivation preferences may reduce the number of patients experiencing distressing implantable cardioverter-defibrillator shocks at end of life.

Outflow Graft Occlusion of the HeartMate 3 Left Ventricular Assist Device

Continuous-flow ventricular assist devices have demonstrated clinical superiority compared with the first-generation pulsatile devices; however, complications continue to affect patients on left ventricular assist device (LVAD) support.1 The recently published MOMENTUM 3 trial (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate3) reported that the HeartMate 3 (HM3) was associated with better outcomes after 6 months when compared with the HM2. None of the patients randomized to the HM3 device had suspected or confirmed thrombosis.2 In this brief report, we describe 2 patients who developed extrinsic occlusion of the outflow graft after HM3 implantation. A 65-year-old man with ischemic cardiomyopathy underwent implantation of an HM3 LVAD as bridge to transplantation. Because of significant epistaxis, acetylsalicylic acid was reduced from 325 to 81 mg daily, whereas international normalized ratio was maintained between 2 and 3. One-year post-LVAD, the patient presented with congestive symptoms and deteriorating renal function. His LVAD had logged multiple low-flow alarms, as low as 1.9 L/min (previously 4–4.5 L/min; Figure [C]). Serum lactate dehydrogenase was 290 U/L (125–220 U/L) and international normalized ratio maintained within therapeutic range. A noncontrast computed tomographic scan of the chest showed no …

Long-term use of left ventricular assist devices: a report on clinical outcomes

Background The literature examining clinical outcomes and readmissions during extended (> 1 yr) left ventricular assist device (LVAD) support is scarce, particularly in the era of continuous-flow LVADs. Methods We completed a retrospective cohort study on consecutive LVAD patients from June 2006 to March 2015, focusing on those who received more than 1 year of total LVAD support time. Demographic characteristics, clinical outcomes and readmissions were analyzed using standard statistical methods. All readmissions were categorized as per the Interagency Registry for Mechanically Assisted Circulatory Support 2015 guidelines. Results Of the 103 patients who received LVADs during the study period, 37 received LVAD support for more than 1 year, with 18 receiving support for more than 2 years. Average support time was 786 ± 381 days, with total support time reaching 80 patient-years. During a median follow-up of 2 years, 27 patients died, with 1-year conditional survival of 74%. Median freedom from first readmission was 106 days (range 1–603 d), with an average length of stay of 6 days. Readmissions resulted in an average of 41 ± 76 days in hospital per patient. Reasons for readmission were major infection (24%), major bleeding (19%) and device malfunction/thrombus (13%). There were a total of 112 procedures completed during the readmissions, with 60% of procedures being done in 13% (n = 5) of patients. Conclusion Continuous-flow LVADs provide excellent long-term survival. The present study describes marked differences in reasons for readmissions between the general LVAD population and those supported for more than 1 year. Prolonged LVAD support resulted in decreased susceptibility to major bleeds and increased susceptibility to infection.