Left Ventricular Assist Device Group Research Articles

Temporary Mechanical Circulatory Support, a New Paradigm in Bridging Patients to Heart Transplantation: Comparing Outcomes versus Durable Left Ventricular Assist Devices

Purpose Use of a novel temporary mechanical support system in the axillary position has emerged as a successful method to bridge patients to heart transplantation (BTT). This system has advantages over durable left ventricular assist devices (LVAD) but comparative outcomes have not yet been evaluated. Methods Patients presenting from 2014-2018 with decompensated heart failure who required an axillary temporary LVAD as BTT were evaluated retrospectively. A comparison group of patients who underwent durable LVAD placement as BTT from the same time period was identified. Demographics and outcomes were evaluated and compared for each group. Results 47 patients underwent an axillary temporary LVAD placement and 92 patients had a durable LVAD placed for BTT. The majority of patients were Intermacs 1 or 2 (46.8% and 48.9%) for the temporary LVAD group, and Intermacs 2 or 3 (32.6% and 30.4%) for the durable LVAD group. Postoperative complications were higher in the durable group for GI bleeding 2.1% vs 14.1% (p=0.034) and stroke 4.3% vs 14.1% (p=0.089), and increased in the temporary group for renal failure at 28.9% vs 14.1% (p=0.062). All-cause mortality was not statistically different, 15.6% vs 13.0% (p=0.793). Thirty-day and 1-year survival post transplantation were nearly equivalent, 100% vs 100% and 94.4% vs 97.1% (p>0.999) respectively. Wait time on the transplant list was significantly longer for the durable LVAD group vs the temporary LVAD group and is shown in table 1. Conclusion Use of a novel temporary LVAD as a bridge to transplantation has excellent outcomes, which compare favorable to the established standard of durable mechanical circulatory support. These results challenge the established paradigm of mechanical support in bridging patients to heart transplantation in light of the new UNOS listing criteria changes. Further studies within the larger national patient population are required to confirm these findings. Use of a novel temporary mechanical support system in the axillary position has emerged as a successful method to bridge patients to heart transplantation (BTT). This system has advantages over durable left ventricular assist devices (LVAD) but comparative outcomes have not yet been evaluated. Patients presenting from 2014-2018 with decompensated heart failure who required an axillary temporary LVAD as BTT were evaluated retrospectively. A comparison group of patients who underwent durable LVAD placement as BTT from the same time period was identified. Demographics and outcomes were evaluated and compared for each group. 47 patients underwent an axillary temporary LVAD placement and 92 patients had a durable LVAD placed for BTT. The majority of patients were Intermacs 1 or 2 (46.8% and 48.9%) for the temporary LVAD group, and Intermacs 2 or 3 (32.6% and 30.4%) for the durable LVAD group. Postoperative complications were higher in the durable group for GI bleeding 2.1% vs 14.1% (p=0.034) and stroke 4.3% vs 14.1% (p=0.089), and increased in the temporary group for renal failure at 28.9% vs 14.1% (p=0.062). All-cause mortality was not statistically different, 15.6% vs 13.0% (p=0.793). Thirty-day and 1-year survival post transplantation were nearly equivalent, 100% vs 100% and 94.4% vs 97.1% (p>0.999) respectively. Wait time on the transplant list was significantly longer for the durable LVAD group vs the temporary LVAD group and is shown in table 1. Use of a novel temporary LVAD as a bridge to transplantation has excellent outcomes, which compare favorable to the established standard of durable mechanical circulatory support. These results challenge the established paradigm of mechanical support in bridging patients to heart transplantation in light of the new UNOS listing criteria changes. Further studies within the larger national patient population are required to confirm these findings.

Assessment of Wall Shear Stress on the Aortic Valve in Patients with Left Ventricular Assist Device Using Vector Flow Mapping

Purpose De novo aortic insufficiency is one of unresolved complications after left ventricular assist device (LVAD) implant. It has been hypothesized that decreased and oscillatory wall shear stress (WSS) on the aortic valve following LVAD implantation cause leaflet degeneration resulting in AI. We developed novel approach to measure WSS on the aortic valve using vector flow mapping (VFM) images. Methods Aortic root color Doppler image was obtained using intraoperative epiaortic echocardiogram in 6 patients who received LVAD implant and 8 patients undergoing LVAD explant and heart transplant. As a control group, we enrolled 5 patients undergoing CABG surgery. Using obtained images, WSS and oscillatory shear index (OSI) on the right coronary cusp (RCC) was calculated with off-line software, Echo VFM® (Cardio Flow Design, Tokyo, Japan) (Figure). Results Image analysis was successful in all patients. The WSS on the ventricularis of the RCC was significantly lower in the LVAD group compared to control (0.09±0.06 vs. 0.35±0.27 Pa, p Conclusion Significantly lower WSS on the ventricularis may be accountable for AV degeneration and subsequent De Novo AI in patients with LVAD.

Cerebral Blood Flow during Exercise in Heart Failure: Effect of Ventricular Assist Devices.

In healthy individuals, cerebral blood flow (CBF) increases during exercise, but few studies have compared changes in CBF during exercise in patients with heart failure (HF) to healthy controls (CTRL) or assessed the effects of left ventricular assist devices (LVAD). We hypothesized that subjects implanted with LVAD would exhibit impaired cerebrovascular responses to cycle exercise when compared with age- and sex-matched healthy CTRL subjects but would have enhanced responses relative to subjects with HF. Internal carotid artery (ICA) blood flow and intracranial middle (MCAv) and posterior cerebral (PCAv) artery velocities were measured continuously using Doppler ultrasound, alongside cardiorespiratory measures at rest and in response to an incremental submaximal cycle ergometer exercise protocol in nine LVAD participants (58 ± 15 yr, 87 ± 16 kg, 172 ± 8 cm, six females), nine age- and sex-matched subjects with HF (58 ± 8 yr, 84 ± 11 kg, 177 ± 6 cm), and nine CTRL (55 ± 14 yr, 74 ± 16 kg, 168 ± 10 cm). At rest, ICA hemodynamics (velocity, shear rate, and flow) were greater in CTRL and LVAD than that in HF (P < 0.05). Higher MCAv (+5.52 ± 1.59 cm·s, P = 0.003) and PCAv (+5.82 ± 1.41 cm·s, P = 0.001) were also observed in LVAD subjects than healthy CTRL. During exercise, ICA flow increased at all workloads in CTRL, but not in HF or LVAD groups. MCAv increased from baseline in both HF and CTRL participants (P = 0.0001), but not in LVAD subjects. Nonetheless, CTRL and LVAD showed higher MCAv (P = 0.006) and PCAv (P < 0.0001) values throughout exercise than HF. Our findings indicate that LVAD subjects exhibit higher CBF at rest and during exercise than matched HF participants but attenuated brain blood flows during exercise when compared with healthy subjects. CBF should be considered when designing exercise training interventions in patients with HF and LVAD.

Reoperative sternotomy is associated with increased early mortality after cardiac transplantation.

Outcomes of cardiac transplantation in patients undergoing reoperative sternotomy are often worse than primary transplants. However, the risks imposed by a prior sternotomy, left ventricular assist device (LVAD) or retransplantation have not been independently analysed. Using the United Network for Organ Sharing (UNOS) database, a retrospective propensity-matched cohort analysis was performed on 14 730 patients who received a heart transplant between 2005 and 2017. Of 7365 patients who underwent a reoperative sternotomy, 4526 (61%) patients had previous cardiac surgery, 2364 (32%) patients had an LVAD and 475 (6%) patients had a previous transplant. Baseline characteristics were compared, and survival was analysed using a Cox model. Compared to patients who underwent a primary transplant, patients with a prior sternotomy had a worse long-term survival (P < 0.001). There was no significant difference in survival between patients who had an LVAD and those who had a previous cardiac operation. However, all subgroups had better survival compared to patients who underwent a retransplant (P < 0.05). On the multivariable analysis, prior sternotomy and radiation demonstrated an increased risk of death compared to primary transplants [prior cardiac surgery: hazard ratio (HR) 1.13, 95% confidence interval (CI) 1.05-1.22; P = 0.001; LVAD: HR 1.19, 95% CI 1.08-1.32; P = 0.001; retransplant: HR 1.68, 95% CI 1.42-1.99; P < 0.001; radiation: HR 1.82, 95% CI 1.00-3.30; P = 0.04]. When excluding patients who died in the first year, there were no significant differences in survival between the primary transplant, prior cardiac surgery, LVAD and retransplant groups. Prior sternotomy is a risk factor for worse survival after cardiac transplantation, mainly due to increased early postoperative mortality. A history of prior transplant confers the greatest risk compared to those who received an LVAD or had prior cardiac surgery.

Effect of Continuous-Flow Mechanical Circulatory Support on Microvasculature Remodeling in the Failing Heart.

Left ventricle (LV) unloading caused by a left ventricular assist device (LVAD) has been shown to enhance reverse LV remodeling in end-stage cardiomyopathy. Several reports consistently suggest that a pulsatile-flow LVAD has more profound effects compared to continuous-flow LVAD, though the responsible mechanisms are not fully understood. We hypothesized that arterial pulsatility, being affected by the type of LVAD, may affect microvasculature and functional/pathological LV remodeling in end-stage cardiomyopathy. The study included 18 patients with chronic heart failure who underwent LVAD implantation. Eight patients were implanted with pulsatile-flow LVAD, and 10 patients were implanted with continuous-flow LVAD. The results of serial echocardiograms and histopathological assessment of transmural LV tissues, which were collected during the implantation and removal of LVADs, were compared between the groups. The results of echocardiography showed that LV systolic dimension and LV ejection fraction improved greatly in the pulsatile-flow LVAD group compared to the continuous-flow LVAD group. Histological analysis showed that in both groups, increased microvasculature density and decreased cardiomyocyte size during LVAD support had no significant difference. In contrast, only the patients with continuous-flow LVADs had presented with significant increase in α-smooth muscle actin (α-SMA)-positive layer thickness and the number of proliferating cell nuclear antigen (PCNA)-positive cells of myocardial arterioles. We concluded that the use of long-term continuous-flow LVAD support, having less pulsatility, had induced more thickening to the medial layer of myocardial arterioles compared to the use of pulsatile-flow LVADs. Our findings suggest that the pathological impairment of myocardial microvascular structure during continuous-flow LVAD support may be a novel mechanism which accounts for the difference in LV remodeling depending on the type of LVAD.

Left ventricle assist devices and driveline's infection incidence: a single-centre experience.

Different left ventricular assist devices (LVADs) are provided of different driveline exit sites: HeartWare HVAD presents abdominal power-cable-supply, while the Jarvik 2000 LVAD is powered by a retroauricular driveline. We analyzed 93 LVAD-implanted patients from January-2009 to October-2016 (41 HeartWare and 52 Jarvik 2000), hypothesizing a different incidence of infection, according to driveline exit site. The two populations were propensity matched for the demographic data and preoperative variables, and the outcomes were further analyzed. Nine driveline infections (DLIs) were in each LVAD group recorded (22% for HVAD and 17% for Jarvik 2000). The incidence of the complication was similar between groups (p = 0.97), even during time (p = 0.27 within 6months and p = 0.16 over 6months of support). Age at implant (p = 0.01), revision for bleeding (p = 0.05), days of postoperative intubation (p = 0.002), and ICU stay (p < 0.001), as well as days on device (p < 0.001) were identified as risk factors for DLIs. The type of device and the driveline exit site were not statistically co-related to infections. Similar infection-freedom survival was identified (p = 0.87). Younger age at implant, revision for bleeding, prolonged mechanical ventilation, delayed rehabilitation, as well as long time LVAD support were identified as risk factors for exit site DLIs. Despite similar incidence of DLIs, the different management and care of the retroauricular exit site makes it more appropriate and comfortable in long-term support.

End-stage heart failure: Two surgical approaches with different rehabilitative outcomes.

BackgroundA rising number of patients are surgically treated for heart failure at the more advanced stage, thanks to the increasing use of left ventricular assist device (LVAD) as a reliable alternative to heart transplantation (HTx). However, it is still unknown whether differences exist between the two surgical approaches in the efficacy of rehabilitation programmes. Therefore, aim of this study was to evaluate whether functional capacity and rehabilitative outcomes differ between HTx and implantation of LVAD.Methods and resultsWe enrolled 51 patients with HTx and 46 with LVAD upon admission to our rehabilitation-unit. We evaluated six-minute walking test (6MWT), resting oxygen saturation (SaO2) and nutritional assessment before and after a standardised cardiovascular rehabilitation programme. HTx and LVAD groups differed in age, anthropometric variables, gender distribution. Upon enrolment, 6MWT distance was similar in the two groups, whereas malnutrition was less frequent and the waist circumference/height ratio (WHtR) was greater in LVAD patients. SaO2 was greater in HTx patients. Rehabilitation improved SaO2, 6MWT distance and nutritional status. The difference in malnutrition disappeared, but WHtR remained higher in the LVAD and SaO2 higher in the HTx patients; the 6MWT distance improved more in the HTx patients. Multivariate linear regression analysis confirmed that the type of intervention was independent predictor of 6MWT distance after rehabilitation.ConclusionsHTx patients improve more rapidly and perform better after rehabilitation, suggesting the need for more tailored rehabilitation training for LVAD patients.

Quality of Life and Mid-Term Survival of Patients Bridged with Extracorporeal Membrane Oxygenation to Left Ventricular Assist Device.

Insertion of a left ventricular assist device (LVAD) improves survival and quality of life (QOL) in patients with class IV heart failure failing medical management. However, QOL and survival of patients bridged to LVAD with extracorporeal membrane oxygenation (ECMO) is unknown. Between July 2008 and June 2014, 213 patients underwent insertion of HeartMate II LVAD at two VAD centers without a bridge with a temporary VAD. Extracorporeal membrane oxygenation was used as a bridge before LVAD insertion in 22 Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) 1 patients (ECMO-VAD group). No bridge was used in 21 INTERMACS 1 patients and 170 INTERMACS 2-4 patients (primary LVAD group). Survival was compared between the ECMO-VAD group and INTERMACS 1 patients who underwent a primary LVAD insertion (INTERMACS 1 group). Quality of life was compared between the ECMO-VAD group and the primary LVAD group as a whole. The in-hospital mortality of the ECMO-VAD and INTERMACS1 groups was 23% and 14%, respectively (P = 0.38). The postimplant QOL scores of the ECMO-VAD group were not different compared with the primary LVAD group. Although the ECMO-VAD group consists of critically ill patients, the QOL and survival after discharge were not significantly different compared with patients who were not bridged with ECMO.

Functional status of United States children supported with a left ventricular assist device at heart transplantation

As survival with pediatric left ventricular assist devices (LVADs) has improved, decisions regarding the optimal support strategy may depend more on quality of life and functional status (FS) rather than mortality alone. Limited data are available regarding the FS of children supported with LVADs. We sought to compare the FS of children supported with LVADs vs vasoactive infusions to inform decision making around support strategies. Organ Procurement and Transplant Network data were used to identify all United States children aged between 1 and 21 years at heart transplant (HT) between 2006 and 2015 for dilated cardiomyopathy and supported with an LVAD or vasoactive infusions alone at HT. FS was measured using the 10-point Karnofsky and Lansky scale. Of 701 children who met the inclusion criteria, 430 (61%) were supported with vasoactive infusions, and 271 (39%) were supported with an LVAD at HT. Children in the LVAD group had higher median FS scores at HT than children in the vasoactive infusion group (6 vs 5, p < 0.001) but lower FS scores at listing (4 vs 6, p < 0.001). The effect persisted regardless of patient location at HT (home, hospital, intensive care) or device type. Discharge by HT occurred in 46% of children in the LVAD group compared with 26% of children in the vasoactive infusion cohort (p = 0.001). Stroke was reported at HT in 3% of children in the LVAD cohort and in 1% in the vasoactive infusion cohort (p = 0.04). Among children with dilated cardiomyopathy undergoing HT, children supported with LVADs at HT have higher FS than children supported with vasoactive infusions at HT, regardless of device type or hospitalization status. Children supported with LVADs at HT were more likely to be discharged from the hospital but had a higher prevalence of stroke at HT.

Contemporary outcome of unplanned right ventricular assist device for severe right heart failure after continuous-flow left ventricular assist device insertion.

The timely use of a right ventricular assist device (RVAD) becomes necessary for severe right heart failure (RHF) after left ventricular assist device (LVAD) insertion. This study evaluates outcomes in patients who required unplanned RVAD support early after continuous-flow (CF) LVAD insertion. We retrospectively reviewed 305 patients who underwent HeartMate II/HeartWare CF-LVAD insertion between 2009 and 2014. Twenty-seven (9%) patients required unplanned RVAD for severe RHF early after LVAD insertion. We compared early and late outcomes in patients with and without RVAD. The median time to RVAD implantation after primary CF-LVAD implantation was 1.0 (0-3) day. Seventeen (63%) patients could be weaned from RVAD after median of 14 (10-18) days. In 278 patients in the isolated LVAD group, overall survival at 3 and 12 months was 95% and 86%, whereas 59% and 54% in the unplanned RVAD group, respectively ( P < 0.001). The 12-month overall survival rate in patients who were weaned from RVAD was 75% ( P = 0.189 vs isolated LVAD group), whereas in patients who could not be weaned from RVAD, the overall survival was 20% ( P < 0.001 vs RVAD weaning group and isolated LVAD group). Readmission free rate for RHF at 1 year was 53% in the unplanned RVAD group and 90% in the isolated LVAD group ( P = 0.002). Among patients who required unplanned RVAD after CF-LVAD implantation, above 60% of the patients could be weaned from RVAD. However, careful attention should be paid to the recurrent or sustained RHF.

Left Ventricular Unloading After Acute Myocardial Infarction Reduces MMP/JNK Associated Apoptosis and Promotes FAK Cell-Survival Signaling

The mechanism underlying left ventricular remodeling and reverse remodeling in the setting of mechanical support following acute myocardial infarction (MI) is unclear. We tested the hypothesis that left ventricular assist device (LVAD) unloading can decrease apoptotic signals after MI. An MI model was created in 16 sheep by coronary artery ligation. Eight were unloaded with a LVAD during the first 2 weeks after MI and observed for 10 more weeks. Myocardial tissue was collected from the nonischemic adjacent zone and the remote zone. Proteins in theapoptotic matrix metalloproteinases (MMPs)-2/c-Jun N-terminal kinase (JNK) and prosurvival β1D-integrin/focal adhesion kinase (FAK) pathway were quantified. Increased TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) positive nuclei were observed in the MI group and to a lesser extent in the LVAD group (6.18 ± 0.26 versus 0.82 ± 0.18; p< 0.05). Pro-MMP-2, MMP-2, JNK, and phosphorylated (p)-JNK were all elevated in the adjacent zone of the MI-only group but not in the adjacent zone of the LVAD-supported group. There were higher levels of prosurvival p-FAK in the LVAD-supported group than in the MI group. MMP-2/JNK apoptotic and β1D-integrin/FAK survival pathways are activated in the nonischemic adjacent zone after MI in adult sheep. LVAD unloading of approximately 50% cardiac output for 2 weeks attenuates remodeling in part by its negative effect on stretch-induced apoptosis and inhibition of MMP-2 activity.

Left Ventricular Assist Devices or Inotropes for Decreasing Pulmonary Vascular Resistance in Patients with Pulmonary Hypertension Listed for Heart Transplantation

BackgroundFixed pulmonary hypertension is common in patients with advanced heart failure and is a contraindication for heart transplantation. Left ventricular assist devices (LVAD) and inotropes have been used to reduce pulmonary vascular resistance (PVR) and allow transplantation. However, little is known about the efficacy of this strategy. MethodsWe queried the United Network for Organ Sharing registry for all adult patients (age ≥18 years) listed for primary heart transplantation (2008–2014) with PVR of >5 wood units (WU) or transpulmonary gradient >16 mmHg who were treated with LVAD or IV inotropes as status 1a, 1b, or 7. We compared waitlist mortality/delisting and absolute changes in hemodynamics between listing and transplantation. ResultsOf 18,009 patients listed during the study period, 1016 were included in the analysis (393 LVAD, 623 inotropes), with a mean age of 52.9 ± 11.6 years, 74% male, and 38% had ischemic etiology. Mean PVR was 5.7 ± 2.4 WU and transpulmonary pressure gradient 19.3 ± 5.3 mmHg. Compared with the inotrope group, LVAD patients were more likely listed as status 1A (32.8% vs 18.1%, P < .001), had lower PVR (5.3 WU vs 5.9 WU, P = .001), and higher cardiac output (4.1 vs 3.6 L/min, P < .001). After a mean of 239 days, PVR decreased by 1.71 WU in the LVAD group vs 1.85 WU in the inotrope group (P = .52). PVR normalization (<2.5 WU) occurred at similar rates among those treated with inotropes and LVAD (30.7% vs 35.6%, P = .228). Waitlist mortality was similar between LVAD and inotropes (adjusted P = .837). Absolute PVR and transpulmonary pressure gradient reductions correlated with time on the waitlist (P < .001 for both comparisons). ConclusionOnly about one-third of patients with fixed pulmonary hypertension achieve normalization of PVR before transplant with either LVAD or inotropes. Similar waitlist mortality was observed among patients bridged with either strategy.

Long‐Term Intra‐Aortic Balloon Pump Support as Bridge to Left Ventricular Assist Device Implantation

The intra-aortic balloon pump (IABP) can be used to bridge critically ill end-stage heart failure patients to left ventricular assist device (LVAD) implantation. However, the IABP's potential association with hemorrhagic complications raises concerns regarding its utilization in these patients. We investigated whether preoperative long-term IABP support increases hemorrhagic complications post-LVAD implantation. Ten patients undergoing IABP support prior to LVAD implantation (IABP-LVAD group) were compared with 16 who did not require IABP support (LVAD group). Mean duration of IABP support was 25.8 days. Preoperatively, both groups were comparable in all measured parameters and indices of end-organ function. Perioperative (defined as three weeks post-LVAD implantation, including the procedure) cellular and noncellular blood transfusion requirements were similar between IABP-LVAD and LVAD groups (19.8 ± 9.95 vs. 19.76 ± 29.69 RBC units, p = 0.96; 3.8 ± 4.14 vs. 2.0 ± 6.44 plateletpheresis units p = 0.84; 23 ± 16.04 vs. 25.14 ± 37.8 fresh frozen plasma units, p = 0.45). Perioperative minimum hematocrit (33.6 ± 5.6 vs. 36.59 ± 4.8, p = 0.38) and minimum platelet count (199 ± 153 vs. 144 ± 65, p = 0.52) were similar in the two groups. Two patients in the IABP-LVAD group and three patients in the LVAD group underwent reoperation post-LVAD implantation for bleeding. Length of ICU stay was longer in the LVAD group but did not reach statistical significance (6.2 ± 6.22 days in the IABP-LVAD group versus 13.45 ± 10.95 days in the LVAD group, p = 0.06). Long-term IABP support as a bridge to LVAD implantation is not associated with increased hemorrhagic complications post-LVAD implantation. doi: 10.1111/jocs.12759 (J Card Surg 2016;31:467-471).

An Extended Role of Continuous Flow Device in Pediatric Mechanical Circulatory Support

Mechanical circulatory support in the pediatric population is currently limited to pulsatile ventricular assist devices (VAD). In recent years, the use of durable, newer generation, continuous flow devices have increased substantially among adults with end-stage heart failure. We examined the extended role of this device in the pediatric population (aged less than 18years). Between 2010 and 2015, 12 patients (median age 7.1 years; range, 3.7 to 17.0; one third of patients were aged 5 years or less) received a HeartWare ventricular assist device (HVAD; HeartWare, Framingham, MA), 11 for cardiomyopathy and 1 for posttransplant rejection. Right VAD support (n= 5; 42%) was provided by a short-term device (Levitronix, Zurich, Switzerland). Overall, 1 patient died (day 638), 8 patients (67%) underwent transplantation, 1 patient (8.3%) recovered, and 2 patients (17%) remain on HVAD. The mean length of support was 150 days (range, 16 to 638). Four patients (33.3%) were discharged home (all left VAD). In the left VAD group (n= 7), 3 patients subsequently received transplants (days 185, 201, and 234, respectively), 1 recovered (day 149), 1 died (day 638), 1 remained on HVAD (day 198), and 1 needed conversion to biventricular assist device (BIVAD [day 73]). In the BIVAD group (n= 5), right VAD was weaned in 3 (60%), all subsequently received transplants, and 2 remained on BIVAD support until transplant (days 16 and 17, respectively). One BIVAD patient required conversion to central cannulation for longer-term support. Four BIVAD patients (80%) were in Interagency Registry for Mechanically Assisted Circulatory Support level 1 before VAD compared with 2 (29%) in the left VAD group (p=not significant). The actuarial survival rate was 100% at 1 year with no neurologic events. The third-generation, continuous flow device can provide durable support in the pediatric population. The selection strategy for patients who benefit most from the device continues to evolve. It is anticipated that a smaller design in the future will benefit an even wider pediatric population with heart failure.

Prognostic Implications of Long-Chain Acylcarnitines in Heart Failure and Reversibility With Mechanical Circulatory Support

BackgroundHeart failure (HF) is characterized by perturbations in energy homeostasis and metabolism. The reversibility and prognostic value of circulating markers associated with these changes remain unclear. ObjectivesThis study sought to describe the metabolomic profiles of patients along the spectrum of systolic HF, determine their association with adverse outcomes in a clinical trial of HF, and evaluate whether identified metabolites change with treatment for end-stage systolic HF. MethodsTo assess association of metabolites with clinical outcomes, we evaluated a population of 453 chronic systolic HF patients who had been randomized to exercise training versus usual care. To assess change in metabolites with mechanical circulatory support, 41 patients with end-stage HF who underwent left ventricular assist device (LVAD) placement were studied. Targeted, quantitative profiling of 60 metabolites using tandem flow injection mass spectrometry was performed on frozen plasma samples obtained prior to randomization, as well as prior to and ≥90 days post-placement in the LVAD group. Principal components analysis was used for data reduction. ResultsFive principal components analysis–derived factors were significantly associated with peak Vo2 levels at baseline in fully adjusted models. Of these, factor 5 (composed of long-chain acylcarnitines) was associated with increased risk of all 3 pre-specified clinical trial outcomes: all-cause mortality/all-cause hospitalization, all cause-hospitalization, and cardiovascular death or cardiovascular hospitalization. Individual components of factor 5 were significantly higher in patients with end-stage HF prior to LVAD placement and decreased significantly post-implantation. ConclusionsIn chronic HF patients, circulating long-chain acylcarnitine metabolite levels were independently associated with adverse clinical outcomes and decreased after long-term mechanical circulatory support. These metabolites may serve as potential targets for new diagnostics or therapeutic interventions. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437)

Abstract 10948: Patient-reported Quality of Life is a Predictor of Outcomes After Left Ventricular Assist Device Compared to Medical Therapy - Results From the ROADMAP Study

Introduction: The ROADMAP study examined outcomes in subjects with non-inotrope dependent advanced heart failure (n-HF) selected for either left ventricular assist device (LVAD) or optimal medical management (OMM). At 12 months, more LVAD subjects achieved the composite endpoint of survival and ≥75m improvement in 6-minute walk distance (6MWD), while all-cause mortality was similar in the 2 groups. This suggests the focus in decision-making should be on health related quality of life (HRQoL). Aim: The aim of this study was to identify predictors of favorable outcome in n-HF patients treated with LVAD or OMM. Methods: We analyzed ROADMAP study data from 200 n-HF pts receiving LVAD or OMM. HRQoL was assessed with the EQ-5D visual analog scale (VAS) that ranged from 0 (worst) to 100 (best) health status. Results: At baseline, both LVAD and OMM group had markedly impaired exertional capacity and HRQoL (Table 1). We found that baseline VAS was a powerful predictor of the utility of LVAD therapy. Subjects with VAS&lt;60 at baseline were more likely to achieve a positive outcome at 12 months (defined as survival with ≥75m 6MWD increase or survival with HRQoL VAS≥60) with LVAD compared to OMM (Table 1) thus favoring LVAD for these patients. No significant difference between treatments was seen for those with VAS≥60 at baseline (Table 1), supporting continued OMM. Similar results were seen when the examined outcome was survival as treated on original therapy (Figure 1). Conclusions: Patients with poor baseline QoL benefit the most from LVAD therapy compared to continued OMM. HRQoL assessed by EQ5D VAS provides valuable information that can aid in identification of suitable candidates for LVAD therapy.

Right ventricular assist device results in worse post-transplant survival

To our knowledge, how the need for a right ventricular assist device (RVAD) with a left ventricular assist device (LVAD) affects outcomes after orthotopic heart transplantation has not been studied in a multi-institutional database. The United Network for Organ Sharing (UNOS) database was queried for all adult orthotopic heart transplantations from the period 2005-2012. Patients requiring a RVAD + LVAD as a bridge to transplant were compared with patients requiring a LVAD only and patients requiring no ventricular assist device (VAD). During the study period, 16,955 orthotopic heart transplantations were performed. Of these, 13,209 (77.9%) patients did not require a VAD, 3,270 (19.3%) required a LVAD only, and 457 (2.7%) required a RVAD + LVAD. The RVAD + LVAD group had the longest length of stay (25.7 days) compared with the no VAD group (20.8 days) and the LVAD-only group (21.1 days) (p < 0.001). On multivariate analysis, requirement of a RVAD + LVAD before transplantation was independently associated with post-transplant mortality (hazard ratio 1.22, 95% confidence interval 1.01-1.49, p = 0.04). Other variables associated with mortality included donor age, pulsatile flow LVAD as a bridge to transplant, prolonged ischemic time, worsening renal function, black race, history of diabetes in recipient, class II panel-reactive antibody >10%, sex mismatch, and extracorporeal membrane oxygenation or mechanical ventilation as a bridge to transplant. The requirement of a RVAD in addition to a LVAD before orthotopic heart transplantation is associated with worse post-transplant outcomes and increased mortality.

Outcomes of Patients with Left Ventricular Assist Devices Undergoing Mesenteric Angiography for Gastrointestinal Bleeding

PurposeTo compare measures of clinical success, such as the need for subsequent intervention and mortality, in patients with left ventricular assist devices (LVADs) undergoing mesenteric angiography for gastrointestinal (GI) bleeding with respect to a control group. Materials and MethodsA retrospective study was conducted on 48 consecutive patients undergoing anticoagulation whose GI bleeding was assessed with angiography between August 2007 and June 2014: 24 patients with LVADs and 24 control patients without LVADs. The χ2 and t tests were used for statistical analysis. ResultsMean ages were 62.1 years ± 9.6 and 74.5 years ± 11.3 in the LVAD and control groups, respectively. No significant difference was observed in hemodynamic instability, presenting hemoglobin level and International Normalized Ratio, or hemoglobin nadir. Two patients with LVADs (8.3%) and 8 control patients (33.3%) had bleeding detected on angiograms (P = .032). Six embolizations were performed in patients with LVADs and 8 were performed in control patients. Clinical success was achieved in 2 of 6 patients with LVADs (33.3%) and 7 of 8 control patients (87.5%; P = .036). Seven patients with LVADs (29.2%) and 1 control patient (4.5%) underwent repeat angiography within 14 days (P = .020). Seven patients with LVADs (29.2%) and 4 control patients (18.2%) required postprocedural endoscopic or operative intervention as definitive therapy (P = .302). All-cause in-hospital mortality rates were 16.7% in the LVAD group and 4.2% in the control group (P = .032), and the respective all-cause 1-year mortality rates were 33.3% and 9.1% (P = .080). ConclusionsA higher rate of clinical failure is observed in patients with LVADs presenting with GI bleeding compared with those without LVADs, with a more frequent need for subsequent endoscopic or surgical intervention.

Further Peripheral Vascular Dysfunction in Heart Failure Patients With a Continuous-Flow Left Ventricular Assist Device: The Role of Pulsatility

ObjectivesUsing flow-mediated vasodilation (FMD) and reactive hyperemia (RH), this study aimed to provide greater insight into left ventricular assist device (LVAD)–induced changes in peripheral vascular function. BackgroundPeripheral endothelial function is recognized to be impaired in patients with heart failure with reduced ejection fraction (HFrEF), but the peripheral vascular effects of continuous-flow LVAD implantation, now used as either a bridge to transplantation or as a destination therapy, remain unclear. MethodsSixty-eight subjects (13 New York Heart Association [NYHA] functional class II HFrEF patients, 19 NYHA functional class III/IV HFrEF patients, 20 NYHA functional class III/IV HFrEF patients post-LVAD implantation, and 16 healthy age-matched control subjects) underwent FMD and RH testing in the brachial artery with blood flow velocity, artery diameters, and pulsatility index (PI) assessed by ultrasound Doppler. ResultsPI was significantly lower in the LVAD group (2.0 ± 0.4) compared with both the HFrEF II (8.6 ± 0.8) and HFrEF III/IV (8.1 ± 0.9) patients, who, in turn, had significantly lower PI than the control subjects (12.8 ± 0.9). Likewise, LVAD %FMD/shear rate (0.09 ± 0.01 %Δ/s−1) was significantly reduced compared with all other groups (control subjects, 0.24 ± 0.03; HFrEF II, 0.17 ± 0.02; and HFrEF III/IV, 0.13 ± 0.02 %Δ/s−1), and %FMD/shear rate significantly correlated with PI (r = 0.45). RH was unremarkable across groups. ConclusionsAlthough central hemodynamics are improved in patients with HFrEF by a continuous-flow LVAD, peripheral vascular function is further compromised, which is likely due, at least in part, to the reduction in pulsatility that is a characteristic of such a mechanical assist device.

PTU-240 Comparison of outcomes of abdominal and colorectal surgery in patients with left ventricular assist devices versus heart transplants

<h3>Introduction</h3> As survival of patients with left ventricular assist devices (LVADs) and cardiac transplantation improves, surgeons must increasingly decide whether and when to operate on them. <h3>Method</h3> We conducted a retrospective review of abdominal and colorectal operations performed on patients with heart transplants or LVADs at a tertiary care hospital in Boston, MA between 2003–2013. Data were collected on comorbidities, anticoagulation and immunosuppression status, intra-and post-operative complications, need for blood product transfusion, type of surgery performed, 24-hr and thirty day mortality, and time post-transplant or LVAD insertion. Statistical testing for significance was done using the two-sided Fisher’s exact test. <h3>Results</h3> Over the 11-year period, 13 patients with LVADs and 32 patients with heart transplants underwent a total of 67 colorectal (22%) and other abdominal (78%) operations. The median time between LVAD insertion or heart transplant and abdominal surgery was 175 days and 765 days respectively. There was a tendency towards a higher proportion of elective (vs emergency) cases in heart transplant (74%) vs LVAD patients (53%) (p = 0.13). LVAD patients were more likely to be anticoagulated, and had an 18% incidence of postoperative bleeding, with a significantly greater proportion of patients requiring blood transfusion within the first postoperative week (47%) compared to transplant patients (8%) (p = 0.001). Venous thromboembolic (VTE) events were also significantly more common in the LVAD group (21%) vs transplant group (0%) (p = 0.01). Subgroup analysis revealed the incidence of VTE was significantly decreased in the LVAD group bridged for surgery (p = 0.0008). Despite all transplant patients being on immunosuppression medication, and 46% on steroids, there was no statistically significant difference in surgical site infections between the transplant (6%) and LVAD (12%) groups (p = 0.59). Mortality within 24 h tended to be higher in the LVAD group (13%) vs transplant group (0%), with borderline significance (p = 0.06). 30-day mortality was significantly higher in the LVAD group (21%) vs transplant group (0%) (p = 0.01). <h3>Conclusion</h3> Surgical outcomes were better in patients who had undergone heart transplantation compared to those with LVADs, especially with respect to the need for postoperative transfusion, the incidence of VTE, and 24-hr and 30-day mortality. The observed tendency to perform fewer elective cases in LVAD patients compared to transplant patients may be a reflection of clinical intuition of this finding. Surgeons should assess these higher-risk patients on a case-by-case basis. Surgeons should also bridge anticoagulation for LVAD patients whenever possible to reduce the risk of VTE. <h3>Disclosure of interest</h3> None Declared.