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Purpose To assess the utility of 18-F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging to diagnose left ventricular assist device (LVAD) infection in patients before positive microbiological cultures. Methods All patients implanted with LVADs between 10/2009 and 10/2019 aged ≥ 18 years old who underwent FDG PET/CT imaging (n=79 patients, n=119 scans) at a single center were retrospectively reviewed. Patients with positive PET/CT were identified and categorized based on microbiological culture results preceding FDG PET/CT. Medical and/or surgical intervention and outcomes were specified in all cases. Positive PET/CT was defined as evidence of FDG uptake along any part of the LVAD. Results 47 patients with increased glucose uptake associated with LVAD components were identified. 17 had prior negative cultures. Of these, four subsequently had definitive diagnosis of LVAD infection by culture of the pump pocket (n=2), driveline exit site (n=3), or blood stream (n=3) (Table 1). There was one patient with positive cultures from the pump pocket and driveline exit site despite negative PET/CT. Conclusion Our results indicate that FDG PET/CT has potential to diagnose early LVAD infection, which would increase the likelihood of successful medical, rather than surgical, management. 13 patients who had negative cultures and positive scans were attributed to peri-operative inflammation. A more robust distinction between diffuse uptake secondary to inflammation and intense focal uptake representative of infection would likely decrease prevalence of false positive results. Future work will investigate this, as well as a potential modality in machine learning image analysis, to more precisely quantify infection signal of LVAD PET/CT.

Purpose Blood pressure (BP) control reduces stroke in LVAD patients. Home monitoring is key for optimal control. Measurement by Doppler is the most reliable non-invasive method. No study assessed the feasibility of Doppler BP obtained by LVAD patients and caregivers. Methods From 3-11/2018, 12 ambulatory patients with Heartware HVAD were recruited and taught to measure BP in 7 steps (1: quiet sitting, 2: cuff placement, 3: find radial artery flow, 4: inflate cuff, 5: deflate cuff, 6: find BP, 7: record BP). All received manual cuffs and Dopplers to check BP up to 3 times/day for 6 weeks, and had weekly reminder phone calls. They were observed to check BP at routine visits, and completed a survey at end of study. We made no medication changes based on home BP. Results Seven patients (median age 57yrs [IQ 44-67], median VAD support 39 days [IQ 32-48], 1 on support for > 1yr) completed the study. Median number of recorded BP was 42 (IQ 22-78). At enrollment, 4 patients easily learned 7 steps, 2 needed reteaching for step 3 or 5, and 1 needed reteaching for both. At follow-up, all completed 7 steps and obtained BP that modestly agreed with BP measured by staff (κ=0.25, 31% agreement, p=0.0002). Diurnal variation (higher afternoon BP) was seen in 2 patients; the rest had no change from morning to evening (Figure). Reasons for BP check failure were “forgetfulness”, “too busy”, “too sick”, or “no help/did not seek help”. Of the 5 patients who dropped out (median age 38yrs, support duration > 9 months), 3 needed reteaching for steps 3-6. Of the 2 patients who easily learned the steps, 1 lost caregiver and was hospitalized too frequently, the other was non-compliant. No one completely failed BP education after reteaching. Conclusion This pilot study demonstrated feasibility of home BP monitoring by Doppler in select patients. Those who failed to obtain daily BP checks tended to have poor social support or were not proficient in the 7-step method. Further data are needed to define and prognosticate diurnal BP variation in LVAD patients.

Purpose Prior reports on minimally invasive LVAD insertion have focused on smaller and/or highly selected populations. Since 2016 we have used the lateral thoracotomy-hemisternotomy (LTHS) technique and the Heartware HVAD as our default approach for all patients. We compare these outcomes to our results with conventional sternotomy (CS). Methods Since April 2016, 58/61 HVAD patients (representing 61/62 total LVAD insertions) underwent LTHS. Two patients had CS due to stem-cell trial restrictions; one had a posterolateral thoracotomy due to hostile sternum . Outcomes of 60 LTHS procedures were compared to 52 CS dating to 2011. Results Preoperative characteristics (Table 1) were similar except for more males in the LTHS group. No patient was excluded from LTHS due to low Intermacs profile, presence of PFO/ASD, or high RV failure risk. Postoperative outcomes are shown in Table 2. Operative time was longer for LTHS. However, cardiopulmonary bypass (CPB) time, RVAD use, intraoperative red blood cell (RBC) transfusion ≥4U, reoperation for bleeding, operative mortality , and hospital length of stay (LOS) were all lower. One-year Kaplan-Meier estimated survival was 90% LTHS vs 65% CS (p=0.003). Conclusion Improved perioperative and long-term outcomes were observed when employing LTHS as the default technique in a large group of unselected patients.

Purpose Exercise tolerance, measured by pVO 2 during cardiopulmonary exercise stress test (CPET), is impaired in patients with LVAD. After LVAD, the right heart is more sensitive to afterload. We hypothesize that high RV afterload during exercise is associated with lower pVO 2 . Methods At routine right heart catheterization (RHC), LVAD patients performed supine bicycle exercise to maximal effort. Hemodynamics and echocardiograms at rest and peak exercise were collected. The same patients underwent CPET on different days as part of routine post-operative monitoring. We used effective arterial elastance (Ea = systolic PAP/stroke volume) to measure RV afterload, as it incorporates both pulsatile and resistive loads. Results Between 11/17 and 9/18, 10 patients (median age 54 years) had RHC, 8 of them had CPET. Time between LVAD and RHC was 244 days (IQ 223-299) and between CPET and RHC was 55 days (IQ 35-126). Work achieved (Watts) during CPET and RHC correlated linearly (α=1.1, p=0.003, R²=0.60). Patients had low pVO 2 (13.2 L/kg/min, IQ 11-18) and high VEVCO 2 slope (34, IQ 32-43) despite normal filling pressures and cardiac output (CO) after LVAD. They had no chronotropic incompetence (reaching 89.5% of max predicted heart rate, IQ 66.4-95.4). Compared to resting state, at peak exercise, filling pressures, CO, RV stroke work index, and RV tissue Doppler (S’) increased. Notably, pVO 2 negatively correlated with Ea at peak exercise and the change in Ea from rest to stress, while VEVCO 2 slope had the inverse correlations (Figure). pVO 2 did not correlate with changes in PCWP, CO, or LVAD flow. Moderate-severe baseline RV dysfunction and mild-moderate TR are associated with worse pVO 2 and VEVCO 2 slope. Conclusion This pilot study is the first to suggest that poor baseline RV function and high RV afterload at peak exercise are associated with worse pVO 2 and VEVCO 2 slope in LVAD patients. The practice of increasing pump speed may not be adequate to improve exercise tolerance and may be harmful to RV function.

Purpose We assessed the influence of preoperative cardiac anatomy and surgical approach on inflow cannula position in Heartware HVAD recipients. Methods We reviewed pre- and postoperative CT scans and echocardiography. Anatomic variables were chosen based on prior studies: LV end-diastolic dimension (LVEDD), axial plane midline-to-apex distance (ApexDist), and coronal-plane LV outflow tract angulation from horizontal (LVOT angle). Surgical technique was conventional sternotomy (CS) or lateral thoracotomy/hemisternotomy (LTHS). Inflow cannula angular deviation from a line intersecting the apex and mitral orifice center was measured in two planes. Anterior plane deviation is toward the superior or inferior free wall. Lateral plane deviation is toward the septum or lateral wall. Total deviation is the sum of the two. Cutoffs for malposition were deviation ≥ 20 deg in any direction or ≥ 40 deg total. Results 99 HVAD patients (43 CS, 56 LTHS) implanted since 2011 with pre- and postoperative CT were included. LVEDD was larger for LTHS (7.2 vs 6.7 cm, p=0.01). ApexDist and LVOT angle were similar between CS and LTHS. Figure shows inflow position by surgical technique. Inferior-wall deviation was common, while no patient had superior wall-directed malposition. Significantly more septal malposition occurred in CS patients (14% vs 2%; p=0.04). Shorter ApexDist predicted lateral wall malposition (p Conclusion Preoperative CT measurements and surgical approach were associated with different morphologies of HVAD inflow malposition. Surgical planning techniques to optimize inflow position are under study.

Background Non-surgical bleeding (NSB) is a major complication among heart failure (HF) patients supported by continuous-flow left ventricular assist devices (CF-LVADs). Understanding the hemostatic defects contributing to NSB after CF-LVAD implantation is crucial for prevention of this adverse event. The aim of this study was to examine the link between platelet glycoprotein Ibα (GPIbα) ectodomain shedding and NSB in CF-LVAD recipients and to identify a potential biomarker of NSB. Methods Serial blood samples were collected from 35 HF patients supported with CF-LVADs. Platelet function was evaluated by a platelet function analysis device and thromboelastography (TEG). Platelet GPIbα shedding, von Willebrand factor (vWF) antigen and vWF collagen binding capacity were determined using enzyme-linked immunosorbent assays (ELISAs). The structural analysis of vWF was performed by gel electrophoresis. These platelet function measures with vWF parameters of the patients who had NSB between 4 and 32 days after CF-LVAD implantation (bleeder) were analyzed against those without NSB (non-bleeder). Blood samples from 7 healthy individuals were collected to obtain healthy reference values for the laboratory assays. Results Elevated GPIbα shedding was found to be a pre-existing condition in all HF patients prior to CF-LVAD implantation. Post-operative level of GPIbα shedding increased and remained elevated in the bleeder group, whereas a consistent decrease was found in the non-bleeder group. A receiver operating characteristic (ROC) analysis indicated that the level of GPIbα shedding had a predictive power of NSB in patients on CF-LVAD support. Conclusions Platelet GPIbα ectodomain shedding which attenuates platelet reactivity is associated with NSB. Plasma GPIbα level may potentially be used to refine bleeding risk stratification in CF-LVAD patients.

Purpose We evaluated the effect of different inflow cannula malposition morphologies on readmission and selected complication rates in Heartware HVAD recipients. Methods Inflow malposition was defined as the angular deviation from a line intersecting the apex and mitral orifice center in two CT imaging planes. Anterior plane deviation is toward the superior or inferior free wall. Lateral plane deviation is toward the septum or lateral wall. Total deviation is the sum of the two. Cutoffs for malposition were deviation ≥ 20 deg in any direction and total deviation ≥ 40 deg. Clinical outcomes were: 30-day and total cardiovascular-related readmissions (CVR; excludes bleeding, infections, noncardiac procedures, transplants); persistent VT/VF (pVT; ≥ 2 episodes); combined pump thrombosis (PT) or embolic stroke (PT-eCVA); and 90-day mortality. Results 99 HVAD patients implanted since 2011 with postoperative CT scans were included. All were followed for complications. 87 were discharged and were assessed for CVR. Prevalence of each morphology of malposition is shown in Table. Deviation toward the inferior free wall occurred most frequently. Eighteen of 87 patients (21%) had 30-day CVR. Total deviation ≥ 40 deg was significantly associated with 30-day CVR (p=0.01). Median total CVR rate was 0.21/100 pt-days (IQR 0-0.68). Inferior wall deviation ≥ 20 deg was significantly associated with total CVR rate (p = 0.03). Eight of 99 patients (8.1%) had PT-eCVA (5 eCVA, 3 PT), 27% had pVT, and 90-day mortality occurred in 7%. No malposition measurement predicted any of these complications. Conclusion PT-eCVA, pVT, and early mortality were not associated with malposition. However, worse overall malposition was associated with 30-day CVR. Inferior wall malposition occurred in half of patients and was associated with overall CVR rate. Improved surgical planning techniques to mitigate malposition are warranted.

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Institutional Affiliations Co-chairs Feldman D: Minneapolis Heart Institute, Minneapolis, Minnesota, Georgia Institute of Technology and Morehouse School of Medicine; Pamboukian SV: University of Alabama at Birmingham, Birmingham, Alabama; Teuteberg JJ: University of Pittsburgh, Pittsburgh, Pennsylvania Task force chairs Birks E: University of Louisville, Louisville, Kentucky; Lietz K: Loyola University, Chicago, Maywood, Illinois; Moore SA: Massachusetts General Hospital, Boston, Massachusetts; Morgan JA: Henry Ford Hospital, Detroit, Michigan Contributing writers Arabia F: Mayo Clinic Arizona, Phoenix, Arizona; Bauman ME: University of Alberta, Alberta, Canada; Buchholz HW: University of Alberta, Stollery Children’s Hospital and Mazankowski Alberta Heart Institute, Edmonton, Alberta, Canada; Deng M: University of California at Los Angeles, Los Angeles, California; Dickstein ML: Columbia University, New York, New York; El-Banayosy A: Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania; Elliot T: Inova Fairfax, Falls Church, Virginia; Goldstein DJ: Montefiore Medical Center, New York, New York; Grady KL: Northwestern University, Chicago, Illinois; Jones K: Alfred Hospital, Melbourne, Australia; Hryniewicz K: Minneapolis Heart Institute, Minneapolis, Minnesota; John R: University of Minnesota, Minneapolis, Minnesota; Kaan A: St. Paul’s Hospital, Vancouver, British Columbia, Canada; Kusne S: Mayo Clinic Arizona, Phoenix, Arizona; Loebe M: Methodist Hospital, Houston, Texas; Massicotte P: University of Alberta, Stollery Children’s Hospital, Edmonton, Alberta, Canada; Moazami N: Minneapolis Heart Institute, Minneapolis, Minnesota; Mohacsi P: University Hospital, Bern, Switzerland; Mooney M: Sentara Norfolk, Virginia Beach, Virginia; Nelson T: Mayo Clinic Arizona, Phoenix, Arizona; Pagani F: University of Michigan, Ann Arbor, Michigan; Perry W: Integris Baptist Health Care, Oklahoma City, Oklahoma; Potapov EV: Deutsches Herzzentrum Berlin, Berlin, Germany; Rame JE: University of Pennsylvania, Philadelphia, Pennsylvania; Russell SD: Johns Hopkins, Baltimore, Maryland; Sorensen EN: University of Maryland, Baltimore, Maryland; Sun B: Minneapolis Heart Institute, Minneapolis, Minnesota; Strueber M: Hannover Medical School, Hanover, Germany Independent reviewers Mangi AA: Yale University School of Medicine, New Haven, Connecticut; Petty MG: University of Minnesota Medical Center, Fairview, Minneapolis, Minnesota; Rogers J: Duke University Medical Center, Durham, North Carolina

Purpose The blood contacting surfaces of a left ventricular assist device (LVAD) is made of biologically inert compounds such as titanium, polytetrafluoroethylene, and acrylics. These inert materials as well as non-physiological high shear stress can affect different cellular processes in recipients. To evaluate the effects of LVAD among congestive heart failure (CHF) patients on oxidative stress and DNA damage repair, the present study have been conducted. Methods and Materials We recruited 5 CHF patients implanted with continuous flow LVADs as bridge to transplant and 5 non-smoking healthy control. Reactive oxygen species (ROS) generation in blood leukocytes and the levels of antioxidant enzyme superoxide dismutase (SOD) in erythrocytes were measured by flow cytometry/immunofluorescence microscopy and spectrophotometry respectively. ELISA was used to measure oxidized low density lipoproteins ( ox LDL) in plasma. γ-H2AX foci count as DNA double strand break marker and different key proteins involved in DNA repair via non-homologous-end-joining (NHEJ) and homologous recombination (HR) were done by immunocytochemistry in lymphocytes. Results Our study clearly indicated that the levels of ROS and ox LDL were significantly higher in CHF patients after LVAD implantation compared to baseline and controls. Moreover, SOD levels were decreased with increasing post-operative days. All the changes indicated oxidative stress among LVAD recipients. Increasing numbers of γ-H2AX foci in lymphocytes were positively correlated with the ROS (r=0.9429) and oxLDL (r=0.9753) and negatively with SOD (r=–0.9924) levels (p Conclusions Our result, for the first time showed that, LVAD not only induce oxidative stress and DNA damage in lymphocytes but also modulates the DNA repair pathways among CHF patients.

Purpose Neurologic events are a devastating complication of LVAD support. Pre-LVAD stroke risk scores are lacking. CHA 2 DS 2 -VASC is an established risk score for ischemic stroke (iCVA) in patients with atrial fibrillation (AF). We hypothesized that it might have predictive value in CF LVAD recipients. Methods and Materials Records for recipients of currently available durable CF LVADs were reviewed. Cox proportional hazards modeling was used to determine association between pre-LVAD variables and: 1) post-LVAD iCVA; or 2) either iCVA or transient ischemic attack (TIA). Patients were censored at death, explant, or ongoing support. In addition to CHA 2 DS 2 -VASC parameters (heart failure; hypertension; age; diabetes; gender; prior iCVA or TIA; vascular disease including myocardial infarction), we tested pre-LVAD Intermacs profile, device type, comorbidity requiring anticoagulation (deep vein thrombosis, pulmonary embolism, LV thrombus, AF), positive heparin antibody, and serum sodium (Na) and albumin (Alb). Lower Na and Alb are predictors of post-LVAD stroke (Kato, J Hrt Lung Transpl 2012;31:1). No patient had a diagnosed hypercoagulable state. Results Of 103 CF LVAD implants (excluding replacements), data were available for 100: 42 Jarvik; 53 Heartmate II; 5 Heartware. 11 (11%) had iCVA, 5 (5%) had TIA, and 1 (1%) had both. Incidence did not differ among devices. For iCVA, CHA 2 DS 2 -VASC was the only significant (at p 2 DS 2 -VASC 2 DS 2 -VASC and Alb were significant predictors. However, the effect of Alb (higher risk with higher Alb) was opposite that shown by Kato et al. No patient with CHA 2 DS 2 -VASC Conclusions In our CF LVAD population, pre-LVAD CHA 2 DS 2 -VASC predicted post-LVAD iCVA or TIA. The Alb effect was incongruent with published data and may require further investigation. We have incorporated this risk score into our pre-LVAD evaluation and plan prospective validation.