Schirger, John A.

Introduction: Baseline hemodynamic parameters have been shown to predict postoperative outcomes such as right ventricular failure (RVF) in LVAD patients. The pressure adjusted heart rate (PaHR) is a hemodynamic parameter that has not been reported in LVAD recipients. Hypothesis: Patients with an elevated PaHR at baseline will have an increased risk of adverse outcomes following LVAD implantation. Methods: Historical cohort study of 273 patients with preoperative invasive hemodynamic assessment before durable LVAD implantation from January 1 st , 2007 to April 10 th 2017. Baseline patient characteristics and hemodynamic parameters were assessed. The primary endpoint was a composite of 30 day mortality, stage 3 acute kidney injury (AKI), and postoperative RVF. Univariate analysis was used to identify predictors of the composite endpoint, which were entered into stepwise backwards multivariate logistic regression to determine independent predictors of the composite outcome. Results: The mean age was 59 and 79% of the patients were male. The median INTERMACS profile was 4 and 166 (60%) of LVADs placed were as destination therapy. The primary composite endpoint was reached by 74 (27%) patient, including 30-day mortality in 13 (5%), severe AKI in 48 (18%) and RVF in 53 (19%). Univariate predictors of the composite endpoint (p <0.05) included atrial fibrillation, INTERMACS profile, home inotropes, preoperative IABP, admission creatinine, baseline Vasoactive-Inotropic Score, mean right atrial pressure (mRAP), mRAP/wedge, mean arterial pressure/mRAP, mean pulmonary artery pressure/mRAP, right ventricular stroke work index (RVSWi), pulmonary artery pulsatility index, and the PaHR. Logistic regression identified PaHR (OR 0.96, 95% CI 0.93-0.99, p=.026), RVSWi (OR 1.002, 95% CI 1.001-1.004, p=.002), home inotropes (OR 0.46, 95% CI 0.22-0.94, p=.034), atrial fibrillation (OR 0.48, 95% CI 0.26-0.88, p=.019) and admission creatinine (OR 0.51, 95% CI 0.34-0.77, p=0.002) as predictors of the composite endpoint. Conclusions: The PaHR is a readily available, novel hemodynamic parameter, that when elevated on baseline hemodynamic assessment can predict those patients at increased risk of postoperative adverse outcomes after durable LVAD implantation.

Introduction: Patients at increased risk of complications following LVAD placement are admitted to the hospital for hemodynamic optimization prior to LVAD implantation, which can include adjustment of medical therapy and/or placement of an IABP. Hypothesis: Prior to LVAD placement patients treated with an IABP during hemodynamic optimization will have similar outcomes despite worse baseline characteristics compared with patients treated medically. Methods: This single-center study included 199 non-inotrope dependent patients who underwent durable LVAD implantation between January 1 st , 2007 and April 10 th 2017. Hemodynamic data was collected retrospectively. Patients who received an IABP were compared to those who did not. Stage 2 or 3 acute kidney injury, right ventricular failure, and 30 day mortality was compared between patients with and without and IABP. Results: The mean age was 62.7 and 82.9% were male; 72 (36.2%) received an IABP. Baseline characteristics between groups were similar. Patients treated with an IABP had worse INTERMACS profiles and worse baseline hemodynamic parameters. The incidence of the primary composite endpoint was similar between patients who had an IABP and those who did not (23.6% vs 19.7%; p=0.517), as were each of the individual endpoints: stage 2 or 3 acute kidney injury (18.1% vs 14.2%; p=0.472), right ventricular failure (13.9% vs 13.4%; p=0.796), and 30 day mortality (6.9 % vs 3.2%; p=0.226). Patients treated with an IABP had greater relative reductions in mean right atrial pressure (-24.1% vs -5.9%; p=0.044), pulmonary artery systolic (-11.7% vs +3.3%; p=<0.001), diastolic (-17.0% vs +12.0%; p=0.015), and mean pressures (-15.2% vs 0.5%; p=<0.001). Conclusions: Despite worse hemodynamic parameters and INTERMACS profile at baseline, ambulatory heart failure patients who received an IABP prior to LVAD implantation did not have an increased incident of stage 2 or 3 acute kidney injury, right ventricular failure, or 30 day mortality, and had more favorable reductions in right atrial and pulmonary artery pressures. These results suggest that the use of the IABP prior to LVAD implantation in non-inotrope dependent patients with poor baseline hemodynamics may mitigate the risk of postoperative complications.

Introduction: While left ventricular assist devise (LVAD) support improves the prognosis of end-stage heart failure (HF) patients, the long-term outcomes remains suboptimal. Improved outcomes may occur with organ protection including reverse myocardial remodeling. Cenderitide (CDNP) is a Mayo engineered designer natriuretic peptide (NP) that co-activates particulate guanylyl cyclase A and B receptors and functions via the second messenger cGMP. We reported a NP deficient state in the heart with LVAD support which lays the rationale for NP replacement therapy with Cenderitide which has cardiorenal protective actions in experimental HF. We sought to determine if Cenderitide co-therapy would be safe and activate cGMP in patients with LVAD support. Hypothesis: Acute single dose of subcutaneous (SQ) Cenderitide will be safe and activate cGMP in patients with LVAD support. Methods: Stable HF patients with LVAD support (Heartmate II, all males) were enrolled in a cross-over design comparing SQ placebo and low (Low-C, 5 ug/kg, n=8) or high dose (High-C, 10 ug/kg, n=8) Cenderitide (Capricor Therapeutics) administration. Vital signs, plasma C(D)NP, cGMP, Aldosterone (Aldo), and NT-proBNP levels were measured before or after drug administration over 24 hours. All parameters in Cenderitide group were adjusted by those in placebo. Results: Both Low-C and High-C group demonstrated significantly increased plasma C(D)NP and cGMP levels for 2 hours after drug injection and those in High-C group showed more prolonged and higher increases than Low-C group. Mean arterial pressure (MAP) in Low-C did not show any changes but in High-C group tended to be lower for 18 hours but this was not significant. Plasma Aldo and NT-proBNP levels in Low-C group did not show any change but those in High-C group tended to be lower after drug injection s similar to the change in MAP. No adverse events were observed in the study. Conclusions: SQ Cenderitide was successfully absorbed, activated cGMP and well tolerated in patients with LVAD support. High dose Cenderitide may have cardiac unloading effects suggested by decreases in NT-proBNP. Further clinical trial for efficacy is warranted to clarify cardiorenal protective effects of Cenderitide in the LVAD population to improve outcomes.

Background: Left ventricle assist device (LVAD) support, a well established therapy in advanced CHF, improves renal function assessed by creatinine. While renal function in large numbers of continuous flow (CF) LVADs vs pulsatile flow (PF) LVADs has been evaluated at 3 mo., long term studies are needed with large numbers of CF vs PF devices. To date longer term analysis comparing renal function in CF vs PF devices have relied on a small number of CF devices. We evaluated renal function assessed by creatinine in a large number of CF (HM II) (n=119) devices and compared this to renal function in a group of subjects treated with PF devices (HM XVE) (n=8) at 6 mo. post implant. Our aim was to evaluate change in creatinine between 3 and 6 months in these groups. Methods and Results: Plasma creatinine was evaluated at 3 and 6 months in two groups: subjects with CF HM II (n=119) and PF LVAD (HM XVE, n=8). The data were collected from two centers in patients undergoing implant for destination or bridge to transplant therapy. Baseline creatinine was higher in the HM XVE group at baseline (BL), and decreased at 3 mo. (1.7 [1.1-2.1] vs 1.1 [0.8-1.5] mg/dL, p<0.05). BL creatine in the HM II group decreased at 3 mo as well (1.2 [1-1.5] vs 1.1 [0.9-1.3] mg/dL, p,0.05). Between 3 and 6 months there was no difference in degree of creatinine change in CF vs PF, however both groups had an increase in Creatinine in this time frame: PF (1.1 [0.8-1.5] vs 1.35 [1.05-1.9] mg/dL, p<0.05); CF (1.1 [0.9-1.3] vs 1.2 [0.92-1.4] mg/dL, p<0.05). Conclusion: This is the first study to demonstrate with large numbers of CF LVAD that creatinine does not incrementally increase between 3 and 6 mo. in comparison to PF LVAD. Further studies are required with large numbers of continuos flow LVADs evaluating the comparative effect of long term continuous flow vs pulsatile flow. Additionally, it remains important to identify surrogates of pulsatility in subjects with continuous flow devices and evaluate prognostic impact on renal function long term.

BACKGROUND: The immunologic risk associated with preformed donor-specific allo-antibodies (DSA) against human leukocyte antigens (HLA) in heart transplant (HTX) recipients is unclear. The goal of this study was to evaluate potential role of DSA on the progression of cardiac allograft vasculopathy (CAV) in HTX recipients. METHODS: The presence of DSA against HLA was evaluated using solid phase Single Antigen Bead assay (One Lambda, Inc., Canoga Park, CA; Luminex platform) before transplant in 35 HTX recipients. Using alloantibody specification analysis, 11% (4/35) and 20% (7/35) had DSA against donor Class I and II HLA respectively including the one patient who had both (DSA I & II+) . 71% (25/35) of patients had no demonstrable DSA (DSA-). All patients had negative cytotoxicity cross match. Baseline three-dimensional intravascular ultrasound studies (3D IVUS) were performed at 1.0 [0.18, 1.4] year after transplant. Follow up 3D IVUS exams were performed 0.92 [0.85, 1.04] years after the baseline exam. RESULTS: The increase in mean plaque (media and intima) volume (PV) was accelerated in the DSA II+ group as compared to the DSA- group (0.87±1.9 mm (3)/mm vs. 0.16±1.8 mm (3)/mm) but the vessel volume index (follow up vessel volume/ baseline vessel volume) was similar between groups (1.08±0.5 vs. 1.09± 0.4; p=0.9). Plaque index (PI) (PV/vessel volume x 100 [%]) increased significantly in the DSA II+ group (17.9±6.3%) but not in the DSA- group (-13.6±13.2%, P=0.02). None of these values were significant in the DSA I+ only group. Treatment with Sirolimus did not affect PI progression between the DSA II+ and DSA- groups (PI progression: 15.9±8.7% vs. -11.7±7.1%, P=0.03). Age, gender, lipid and uric acid levels, prevalence of diabetes, ischemic time, time between IVUS examinations, the use of steroids, mycophenolate vs. azathioprine or calcineurin inhibitors vs. sirolimus were not different between the groups (P>0.4 for all). CONCLUSIONS: Heart transplant recipients with clearly defined anti-Class II DSA are at risk for accelerated cardiac allograft vasculopathy. Whether interventions to minimize the risk of DSA such as virtual crossmatch, desensitization and complement inhibition will retard CAV remains to be proven.

AbstractObjectiveEndomyocardial biopsy (EMB) is a useful diagnostic tool though the yield may be limited in many myocardial diseases. Data on the diagnostic yield and prognostic significance of EMB guided by abnormal electrograms (EGM‐Bx) in suspected cardiac sarcoidosis (CS) are scarce.MethodsSeventy‐nine patients (mean age: 56 ± 12 years; 61% men) with suspected CS based on clinical and imaging features underwent right or left ventricular EGM‐Bx guided by electroanatomic mapping. Tissue samples were obtained from sites with abnormal EGMs and/or abnormal cardiac imaging. The diagnostic yield of EGM‐Bx was evaluated in reference to histopathologic analysis. Left ventricular assist device (LVAD) and transplantation‐free survival were compared between patients with positive and negative EGM‐Bx for CS.ResultsA total of 254 samples were obtained from abnormal EGM sites, and 126 samples from normal EGM sites guided by pre‐procedure imaging findings. Abnormal histopathology was noted in 65 (26%) and 10 (8%) samples from abnormal and normal EGM sites, respectively. Histopathology confirmed CS in 16 (20%) patients, while an alternative tissue diagnosis emerged in 10 (13%) patients. Abnormal EGMs at the biopsy site had sensitivity 89% and specificity 33% for a histopathologic diagnosis of CS. LVAD and transplantation‐free survival were not significantly associated with the EGM‐Bx result (log‐rank p = .91).ConclusionIn patients with suspected CS, abnormal EGM‐Bx has high sensitivity and low specificity for establishing a definite CS diagnosis. Consideration of substrate abnormalities apparent on preprocedural imaging as an adjunct for selection of biopsy sites may further improve EGM‐Bx yield.

Introduction: Recent reports have documented an abrupt increase in 3-month confirmed HeartMate II left ventricular assist device (LVAD) thrombosis beginning in 2011 without a plateau observed to date. Because very little data exist from multi-institutional efforts, we report our experience. Methods: From January 2004 to December 2013, 516 pt underwent HeartMate II LVAD implant at three institutions (University of Michigan (n=254), Mayo Clinic Rochester (n=205), and Vanderbilt Heart and Vascular Institute (n=57)). Median age at implant was 60 yr (range, 18-82) and 428 (83%) were male. Confirmed pump thrombosis at 3 months was defined as thrombus found in the blood-contacting surfaces of the pump at the time of urgent transplant, device exchange or autopsy. Pt without at least 3 months of follow-up were excluded. Results: Confirmed pump thrombosis occurred in 9 pt within 3 months post implant. The incidence was greatest in the year 2012 (5.3%). Following this peak, the incidence of 3-month confirmed pump thrombosis decreased significantly to 2.9% (Figure). Significant differences in preoperative characteristics between patients with pump thrombosis and without thrombosis included female sex (36% vs. 16%, p=0.01), bridge to transplant (77% vs. 54%, p=0.03), atrial fibrillation (55% vs. 32%, p=0.04), and preop platelet count (231,000 vs. 172,000, p<0.001). Follow-up was available in all for a total of 857 patient years of support. At a median follow-up of 1.2 years (max., 9.8 years), a similar proportion of patients were alive (73% vs. 74%, p=0.9). Conclusions: We report a recent decrease in early, confirmed HeartMate II LVAD thrombosis to historically observed levels, which is disparate to recent reports. While we identified several differences in clinical characteristics between patient groups, the issue of pump thrombosis is complex and multifactorial. Most importantly, our findings demonstrate the need for more granular analyses from collaborative efforts.

Introduction: Frailty has recently been shown to be associated with increased risk of death after continuous-flow left ventricular assist device (CF-LVAD) implantation as destination therapy (DT), but no data exists specifically analyzing its association with specific early and late adverse events. Methods: Between February 2007 and May 2014, 251 patients (205 male) underwent primary implantation of CF-LVAD at our institution; 157 (63%) were implanted as DT and preoperative frailty assessment was available in 96 pt. Frailty was identified in 58/96 (60%) patients according to the deficit index (31 impairments, disabilities and comorbidities) and defined as > 25% deficits. Age (67 vs. 64 years, p=0.12), male sex (79% vs. 87%, 0.63), chronic kidney disease (64% vs. 63%, p=0.74), creatinine (1.7 vs. 1.5, p=0.1), hemoglobin (11.6 vs. 11.5, p=0.98), and albumin levels (3.7 vs. 3.8, p=0.53) were similar between frail and non-frail pt, while diabetes (59% vs. 13%, p<0.001), ischemic etiology (64% vs. 45%, p=0.04), and preop balloon pump (50% vs. 26%, p=0.01) were significantly different. Results: All patients underwent CF-LVAD implantation and cardiopulmonary bypass time was similar between groups (102 vs. 111 min., p=0.3). There were no significant differences in early adverse events between frail and non-frail pt, including inotrope duration (120 vs. 96 hr., p=0.11), right ventricular failure (19% vs. 13%, p=0.44), respiratory failure (26% vs. 18%, p=0.34), acute renal failure (16% vs. 13%, p=0.69), and hepatic dysfunction (16% vs. 13%, p=0.69). Median length of stay (20 vs. 16 days, p=0.25) and early mortality (12% vs. 8%, p=0.48) were also similar. During a median follow up of 2 years with 224 patient/years of support, any GI bleed (43% vs. 42%, p=0.79), any thromboembolic event (34% vs. 39%, p=0.74), and driveline infection (10% vs. 26%, p=0.052). Conclusions: In this select cohort of patients, frailty did not portend higher risk of adverse events after CF-LVAD implantation for DT despite prior observation that late survival is reduced in these patients. These findings are extremely important in patient selection and counseling of patients prior to LVAD implantation.

Background: Preclinical diastolic dysfunction (PDD) is defined as subjects with normal systolic function, moderate or severe diastolic dysfunction determined by Doppler criteria but with no symptoms of heart failure (HF). We have previously demonstrated that an impaired cardiorenal endocrine response to stress by acute volume loading (AVL) exists in PDD and that is corrected by acute administration of sq B-type natriuretic peptide (BNP). Type V phosphodiesterase (PDEV) metabolizes cGMP, second messenger of BNP. The objective of the current study is to determine if the combination of PDEV inhibitor (PDEVI) and BNP will result in a greater enhancement of the cardiorenal response to AVL as compared to PDEVI alone in PDD. Methods: Randomized double-blind single placebo-controlled cross-over study in 20 PSD subjects. We determined cardiorenal effects of PDEVI with Tadalafil (T) 5 mg alone and in combination with acute sq BNP (Nesiritide 10 μg/Kg), in response to AVL (normal saline 0.25 ml/kg/min for 1 hour). Each subject had 2 study visits, separated by at least 1 week. At each visit, echocardiogram and renal clearance studies with iothalmate and PAH to measure GFR and renal plasma flow (RPF) were done before and after AVL. Each patient was randomized to receive T at both visits and either placebo or sq-BNP one visit and crossover to the other on the next visit. Results: T+BNP resulted in smaller LA volume index (-4±10 vs 3±7 ml/m 2 , p< 0.05) and lower right ventricular systolic pressure (-4±3 vs 2±6 mmHg, p< 0.05) in response to AVL as compared to T alone. Moreover, T+ BNP resulted in a significant reduction of plasma ANP and LV end-systolic volume in response to AVL while T alone did not. However, the combination to T+BNP did not enhance the renal response to AVL as compared to T alone. Both the change in urine flow (1.7±5 vs 2.4±5 ml/min, p> 0.05) and sodium excretion (129±200 vs 124±270 mEq/min, p>0.05) in response to AVL were similar between T+BNP and T alone. Conclusion: In PDD, the combination of PDEVI and BNP reduced LV filling pressure in response to AVL as compared to PDEVI alone. However, it did not enhance the renal response to AVL. This suggests a differential cardiac versus renal response to the maximization of cGMP system with PDEVI and BNP.

BACKGROUND: AlbuBNP is a novel recombinant human BNP serum albumin fusion protein which possesses a significantly longer elimination half-life compared to BNP. To date, it remains unclear if this novel protein which represents a single molecule of BNP synthesized with the carrier protein albumin can enter the post glomerular/tubular system due to the fusion of BNP to albumin and mediate renal actions. We hypothesized that this fusion protein will have potent renal actions and possess prolonged renal hemodynamic enhancing and excretory properties based upon its unique structure as compared to native BNP. METHODS: We compared the cardiorenal and humoral actions of intravenous(IV) bolus of administration of AlbuBNP (Cardeva, CoGenesys, Rockville MD) (5 mg/kg, n=7) and Human BNP (Phoenix Pharmaceutical, Belmont CA) (25 μ g/Kg, n=5) in two groups of normal anesthetized dogs. * p<0.05 RESULTS: Single IV bolus of AlbuBNP resulted in a sustained increase in plasma cGMP (5±1 to 9±2 pmol/ml*) and urinary cGMP excretion (1136±113 to 2556±417 pmol/min*), markers of the biological activity of BNP, which remained elevated at the termination of the experiment at 270 minutes. In contrast, with human BNP, both plasma and urinary cGMP peaked at 30 minutes and returned to baseline by 150 minutes. In a similar fashion, there was a sustained increase in natriuresis (39±12 to 159±38 μEq/min*), diuresis (0.2±0.1 to 1.1±0.3 ml/min*), renal blood flow (220±22 to 301±33 ml/min*), and glomerular filtration rate (34±2 to 62±13 ml/min*) with AlbuBNP while with human BNP, these renal effects peaked at 30 minutes and returned to baseline by 150 minutes. Furthermore, there was a gradual and sustained suppression of plasma aldosterone (7.8±2 to 3.6±1 ng/dL*) with AlbuBNP. Likewise, there was a more sustained reduction of cardiac filling pressures with AlbuBNP as compared to human BNP. CONCLUSION: We report for the first time that this newly developed BNP/albumin fusion protein has a more prolonged and sustained renal enhancing properties compared to human BNP. Thus, AlbuBNP (Cardeva) represents a novel long-acting renal enhancing and aldosterone suppressing drug which has therapeutic potential for the management of cardiovascular and renal diseases that should be defined in further studies.