Abstracts
558 Temporary Mechanical Circulatory Support as a Bridge to Heart Transplantation: Insights from the UNOS Database A.K. Okoh,1 S. Fugar,2 M. Schulthies,3 M. Russo,1 R. Karanam,1 M. Zucker,1 R. Yanagida,1 and M. Camacho.1 1RWJ Barnabas Health Newark Beth Israel Medical Center, RWJ Barnabas Health Newark Beth Israel Medical Center, Newark, NJ; 2Division of Cardiology, Rush University Medical Center, Chicago, IL; and the 3RWJ Barnabas Health Newark Beth Israel Medical Center, Newark, NJ. Purpose: In patients with decompensated advanced heart failure (HF), full hemodynamic support can be provided by temporary mechanical circulatory support (tMCS) devices. We describe outcomes with the use of tMCS for bridge to decision (BTD) in decompensated advanced HF patients from a nationwide database. Methods: The United Network for Organ Sharing (UNOS) database was queried to identify patients supported with a tMCS device and had a heart transplant between 2009 and 2017. Those with incomplete data were excluded. Demographics, procedural characteristics, and post-transplant outcomes were analyzed. Results: Out of 510 patients, 212 met the inclusion criteria between 2009 and 2017. All were inotrope dependent. Mean § SD age was 45 § 17 years. Mean duration of support was 8 days (range, 0-36days). Eighty-two patients (39%) were bridged to HTx with a tMCS, 82 (39%) recovered prior to HTx and had the device explanted, while 48 (22%) bridged with a durable ventricular assist device (VAD). Post-transplant survival at 1-year was comparable in all three groups. [Immediate bridge: 85% vs. Bridge to recovery: 92% vs, Bridge with durable VAD: 87%, p=0.478] Compared to the other two groups, the incidence of post-transplant dialysis was significantly higher in the immediate bridge group (p=0.029). Conclusion: Temporary MCS a BTD strategy for patients with advanced HF and acute hemodynamic instability. A higher incidence of post-transplant dialysis is noted among patients who are immediately bridged to transplant. The safety and effectiveness of these devices should be further investigated by prospective studies.
559 Novel Percutaneous Dual Lumen Cannula Right Ventricular Assist Device Provides Effective Support for Patients after Left Ventricular Assist Device Implantation M. Salna, A.R. Garan, A. Kirtane, D. Karmpaliotis, P. Green, T. Vahl, H. Takayama, J. Sanchez, P. Kurlansky, M. Yuzefpolskaya, P.C. Colombo, Y. Naka and K. Takeda. Columbia University Medical Center, New York, NY. Purpose: The indications, efficacy, and safety profile of temporary, percutaneous dual lumen cannula-based right ventricular assist devices (RVAD) [TandemLife ProtekDuo] after left ventricular assist device (LVAD) placement have not been well characterized. We describe our experience with the largest series of patients reported to date.
S231 Methods: We conducted a retrospective review of 24 patients who received ProtekDuo RVAD support from January 2016 through July 2018. Outcomes of interest included indications for support, procedural success, complications, and clinical outcomes. Results: Patients were 79% male (n=19) with a median age of 66 (IQR 5872). ProtekDuo RVAD support was initiated a median of 1 day (IQR 0-2) after LVAD implantation. Indications for RVAD placement included pure RV failure (n=14, 58%), vasoplegia (n=2, 8%), or mixed syndrome (n=8, 33%). Procedural success was 100% without any complications. Initial median flow was 4.1 L/min (IQR 3.8-4.5) with a median indexed flow of 2.0 L/min/m2 (IQR 1.8-2.3). During a median support of 11 days (IQR 714), major complications included cannula thrombosis (n=1), cannula migration into the RV requiring repositioning (n=2), and hemolysis, as defined by progressively rising LDH and plasma free hemoglobin levels (n=4). A total of 18 patients (75%) were weaned from the ProtekDuo RVAD with cannulas removed at the bedside in all patients. Three patients died while on ProtekDuo support and three were converted to central RVAD support. Overall survival to discharge was 78% (n=18/23) with one patient remaining in-hospital. Survival post-discharge was 100% at the time of most recent follow-up, with a median duration of 211 days (IQR 98-523). Conclusion: The ProtekDuo RVAD affords a safe and reliable bridge to right ventricular recovery as a less invasive percutaneous option after LVAD placement.
560 Direct Cavo-Pulmonary Stent Mounted Right Ventricular Assist Device J. Park, and P. Bonde. Yale School of Medicine, New Haven, CT. Purpose: Right ventricular (RV) dysfunction following LVAD placement can limit the benefits of LVAD therapy. Distinct anatomical and hemodynamic characteristics of RV limits the use of current LVAD as an RVAD, signifying the clinical need for dedicated RVAD technology. Methods: RVAD delivery system is designed to deploy through percutaneous access to SVC and direct puncture of RPA. The design includes three separate self-expandable open stents linked in series, top stent anchored to the direct puncture from SVC to RPA, middle cage stent freely located at right atrium to prevent right atrial wall suction, and the bottom stent fixed to IVC to assure RVAD positional stability. The top stent incorporates pump and isolation/maintenance system connected to a pacemaker-size controller that is wirelessly powered. Results: 2D cross-sectional CT image shows proximity between SVC and RPA. Based on this structural relationship, RVAD that pumps blood from SVC to RPA was designed and performance for each component was tested in a mock circulatory system. Prototypes were created using 3D printers with either Polylactic Acid (PLA) or watertight material, resin. Both simulation and benchtop experiment study showed excellent performance particularly for RVAD use by providing high-volume/low-pressure (5L/min at 30 mmHg). A gear driven valve having holding torque of 15 N¢mm could successfully isolate system by making zero flowrates. Both pump and isolation/maintenance system were synchronously controlled by wireless power delivery system with total power consumption less than 5W. Conclusion: Our proposed delivery system exploits the unique relations of blood vessels around the heart to allow endovascularly implantable RVAD device.
S232
The Journal of Heart and Lung Transplantation, Vol 38, No 4S, April 2019 D.M. McNamara,2 and M.A. Simon.2 1Emory University, Atlanta, GA; 2 University of Pittsburgh Medical Center, Pittsburgh, PA; 3University of Pittsburgh School of Medicine, Pittsburgh, PA; and the 4University of Pittsburgh Vascular Medicine Institute, Pittsburgh, PA.
561 Unexpected Contribution of Pulsatility to Pump Thrombosis J. Engelman, K. Muthiah, P. Jain, D. Robson, P. Jansz and C. Hayward. Heart Failure and Transplant Unit, St Vincent's Hospital, Sydney, Australia. Purpose: Diminished pulsatility during continuous flow left ventricular assist device (CF-LVAD) support has been hypothesized to be a causative factor for adverse events, such as neurological events (NE), pump thrombus (PT) and gastrointestinal bleeding (GIB). We assessed outcomes between CF-LVAD patients according to measured pulsatility. Methods: Log-files from 61 HVAD (HeartWare) patients with pulsatility data were analyzed. Mean, peak, trough flow and pulsatility (peak - trough flow) were extracted. Flow pulsatility index (PI), defined as pulsatility/ mean flow, was calculated for each patient at 1, 3, 6, 9 and 12 months. Patients were categorized into low, intermediate and high PI tertiles (table 1). Baseline demographic factors and outcomes (NE, GIB, PT) were compared. NE included both cerebrovascular accidents and transient ischemic attacks. One way ANOVAs and chi-square analyses were performed to analyze continuous and categorical variables respectively. Results: There were no significant differences in demographics between the 3 groups according to pulsatility. Surprisingly, there was a significantly higher rate of PT in the high PI group compared to the low and intermediate groups (p=0.013). Factors that contribute to the PI demonstrated that low trough flow was an independent predictor of PT according to logistic regression (OR 0.205, p=0.028). Marginally higher rates of NE were found in the high PI group compared to the low and intermediate groups, however this was not statistically significant (p=0.30). There were no differences in rates of GIB between groups. Conclusion: High PI, particularly driven by low trough flow, was associated with an increased risk of PT highlighting an important therapeutic target for potential prevention or intervention for PT.
Table 1
Demographics and Outcomes according to PI Group
Variables median (range) Age at Implant (yrs) Male n(%) Duration of Support (days) Outcomes n(%) Alive Transplanted Dead Gastrointestinal Bleeding Neurological Event Pump Thrombus
Low PI (<0.85) n=19
Intermediate PI High PI (0.85-1) n=21 (>1) n=21
56 (36-70) 52 (39-68) 16 (84.2) 18 (85.7) 312 (119-1032) 284 (36-985) 12 (63.2) 5 (26.3) 2 (10.5) 2 (11) 3 (17) 0 (0)
10 (47.6) 9 (42.9) 2 (9.5) 2 (10) 4 (19) 1 (5)
p-value
60 (33-76) 0.354 15 (71.4) 0.445 305 (59-811) 0.913 0.613 11 (52.4) 8 (38.1) 2 (9.5) 2 (10) 1.000 8 (36) 0.298 6 (29) 0.013
562 CCR5 Expression is Lower in Women, and Mediates Sex-Based Differences in Post-LVAD Right Ventricular Failure A. Nayak,1 A.A. Morris,1 C.M. Sciortino,2 C. Neill,3 R.L. Kormos,2 C. McTiernan,4 J. Larsen,3 T.N. Bachman,4 K. Hanley-Yanez,4
Purpose: Women have increased risk of right ventricular failure (RVF) after LVAD implant, however the underlying pathophysiology is unknown. Chemokines are inflammatory signaling molecules, and fundamental to cardiac homeostasis and stress adaptation. Prior studies have demonstrated a cardioprotective role for chemokine receptor-5 (CCR5) in viral myocarditis and severe Chagas cardiomyopathy, and that sex hormones modulate CCR5 gene expression. We have previously shown that CCR 3-8 down-regulation is predictive of RVF and 1-year survival after implant. We hypothesized that CCR5 expression mediates sex-based differences in post-LVAD RVF. Methods: CCR expression was examined in patient’s peripheral blood 24 hours pre-LVAD. RNA was isolated using PAXgene protocol. Gene expression was assessed using a targeted microarray (RT2 Profiler PCR array, Qiagen). Results were expressed as PCR cycles to threshold (CT). DCT was calculated as (CCR gene CT) - (HPRT1 control gene CT), and log2 transformed for analysis. Log-fold differences in expression were reported using 2¡DDCT method. RVF was defined as both planned and unplanned RVAD requirement. Multivariable logistic regression was used to determine the association of sex with RVF, adjusting for significantly different covariates (p<0.05) from Table 1. Results: We analyzed 111 LVAD patients (mean age: 53.57 § 13 years, 18% female, 17.1% black). The criteria for RVF was met in 35 (31.5%) patients. Women had increased incidence of RVF (50% vs. 27.5%, p=0.047), and under-expressed CCR5 (1.41 fold decrease, p=0.012) compared to men. After controlling for age, heart failure etiology, albumin, BUN, creatinine and cardiac output, women had a higher risk of RVF (HR: 3.18, 95% CI: 1.04-9.8, p=0.043). Addition of CCR5 as a covariate to the model attenuated the association of female sex with RVF (HR: 2.86, 95% CI: 0.91-8.97, p=0.071). Conclusion: Pre-implant CCR5 expression is lower in women than in men and may mediate sex disparities in post-LVAD RVF.