National Landscape of Hospitalizations in Patients with Left Ventricular Assist Device. Insights from the National Readmission Database 2010-2015

The number of patients with left ventricular assist devices (LVAD) has increased over the years and it is important to identify the etiologies for hospital admission, as well as the costs, length of stay and in-hospital complications in this patient group. Using the National Readmission Database from 2010 to 2015, we identified patients with a history of LVAD placement using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code V43.21. We aimed to identify the etiologies for hospital admission, patient characteristics, and in-hospital outcomes. We identified a total of 15,996 patients with an LVAD, the mean age was 58 years and 76% were males. The most common cause of hospital readmission after LVAD was heart failure (HF, 13%), followed by gastrointestinal (GI) bleed (11.8%), device complication (11.5%), and ventricular tachycardia/fibrillation (4.2%). The median length of stay was 6 days (3-11 days) and the median hospital costs was $12,723 USD. The in-hospital mortality was 3.9%, blood transfusion was required in 26.8% of patients, 20.5% had acute kidney injury, 2.8% required hemodialysis, and 6.2% of patients underwent heart transplantation. Interestingly, the most common cause of readmission was the same as the diagnosis for the preceding admission. One in every four LVAD patients experiences a readmission within 30 days of a prior admission, most commonly due to HF and GI bleeding. Interventions to reduce HF readmissions, such as speed optimization, may be one means of improving LVAD outcomes and resource utilization

Pulmonary Function Testing and Outcomes after Left Ventricular Assist Device Implantation

BACKGROUND: Pulmonary function testing (PFT) is often done during workup prior to left ventricular assist devices (LVAD), but its utility for predicting outcomes and changes in pulmonary function post-LVAD is not well established. We assessed the association of baseline PFT metrics with outcomes after LVAD, and quantified the changes in PFTs post-LVAD. METHODS AND RESULTS: A retrospective study of 178 patients receiving continuous flow LVADs was conducted. A total of 129 subjects had baseline PFT data and 54 of these had repeat tests after LVAD. We collected PFT data (FEV1, FVC, FEV1/FVC ratios, and DLCO) at baseline and post-LVAD, and tested the association with survival, right heart failure, quality of life (Kansas City Cardiomyopathy Questionnaire [KCCQ]) and functional capacity (six-minute walking distance [6MWD]). Proportional hazards and linear regressions determined relationships between baseline PFT data and survival time and functional outcomes, respectively. Paired t-tests compared pre- and post- LVAD PFT variables. There was no association of baseline PFT parameters with survival time post-LVAD (all P \u3e .2), nor the incidence of perioperative RV failure (all P \u3e .15). There were no significant associations of the baseline PFT metrics with the change in KCCQ or 6MWD. There were statistically significant declines in FEV1, FEV1/FVC ratio, and DLCO after LVAD (P \u3c .05). CONCLUSION: In this single center study, there was no relationship between baseline PFTs and post-LVAD outcomes, and PFT parameters often worsened after LVAD. Further studies are needed to determine whether PFTs are useful in this setting, and what, if any, impact LVAD therapy has on pulmonary function

Anticoagulation of Percutaneous Ventricular Assist Device Using Argatroban-Based Purge Solution: A Case Series

Impella devices are percutaneously inserted ventricular assist devices which require a continuous purge solution that contains heparin to prevent pump thrombosis and device failure. We describe 2 patients with heparin-induced thrombocytopenia (HIT) supported with an Impella device utilizing an argatroban-based purge solution. Case 1 involved an 83-year-old female with biventricular failure which resulted in right ventricle Impella support. The purge solution was changed to include argatroban due to concern of device clotting in the setting of HIT. Case 2 involved a 55-year-old male with worsening cardiogenic shock which resulted in left ventricle Impella support. Due to decreased purge flow rates and concerns for clotting, argatroban was added to the purge solution. Both patients\u27 total argatroban regimens were monitored and adjusted by pharmacy, resulting in therapeutic anticoagulation without any major bleeding or thrombotic events. Subsequently, a protocol was designed and implemented. These case reports appear to demonstrate the safe and effective use of argatroban purge solutions for the necessary anticoagulation with an Impella device. Further studies are needed to confirm these results and determine the optimal dosing regimen

Chronic narcotic use increases mortality rates in heart transplantation

Purpose: In kidney and liver transplantation, chronic narcotic use pre and posttransplant has been associated with an increased risk for rejection and early graft loss. There is a paucity of information on the adverse clinical outcomes associated with chronic narcotic use in heart transplant (HT) recipients. Methods: We conducted a retrospective chart review of adults who underwent HT at our institution from January 1, 2007 to June 30, 2016 using electronic medical records. Patients were stratified into groups by narcotic use. Chronic narcotic use (CNU) was defi ned as positive or negative at 6 months prior to transplant (pre transplant) and 6 months post-transplant. Univariate two-group comparisons were carried out using independent two-group t-tests for continuous variables, and chisquare tests for categorical variables. Survival distributions were compared between groups using log-rank tests. Results: 115 underwent HT, 81% were male, mean age 53.8 ±11 years, 48% white and 43% black. CNU pre transplant (N=26) had more illicit drug use (58% vs 28% p=.005), psychiatric history (77% vs 49% p=.013) and criminal history (38% vs 16% P=.012) than those without narcotic use pre-transplant. CNU post-transplant (N=32) had more illicit drug use (50% vs 29% p=.033), psychiatric history (75% vs 48% p=.010) and criminal history (38% vs 14% P=.006) than those without narcotic use post-transplant. No differences were observed in the rate of rejection amongst the groups. Table 1 contains the median survival time in months along with 1-, 3-, and 5-year survival probabilities with their standard errors (SE) of both groups. The 1-, 3-and 5-year survival is worse in patients with CNU post-transplant. Table 1: Survival by Narcotics Variable Median survival time in months (95% CI) 1-year survival probability (SE) 3-year survival probability (SE) 5-year survival probability (SE) P-Value No narcotics pre transplant 119.6 (109.6, N/A) 0.898 (0.03) 0.835 (0.041) 0.835 (0.041) 0.098 Narcotics pre transplant N/A (20.5, N/A) 0.769 (0.08) 0.690 (0.09) 0.690 (0.09) No narcotics post-transplant 119.6 (109.6, N/A) 0.916 (0.03) 0.887 (0.04) 0.887 (004) 0.002 Narcotics post-transplant N/A (19.2, N/A) 0.750 (0.08) 0.625 (0.09) 0.590 (0.09) Conclusion. Patients without CNU post-transplant have higher survival probabilities at each of the three time points than those with CNU post-transplant. Additional studies are warranted to confi rm observed associations

Anticoagulation of Percutaneous Ventricular Assist Device Using Argatroban-Based Purge Solution: A Case Series

Impella devices are percutaneously inserted ventricular assist devices which require a continuous purge solution that contains heparin to prevent pump thrombosis and device failure. We describe 2 patients with heparin-induced thrombocytopenia (HIT) supported with an Impella device utilizing an argatroban-based purge solution. Case 1 involved an 83-year-old female with biventricular failure which resulted in right ventricle Impella support. The purge solution was changed to include argatroban due to concern of device clotting in the setting of HIT. Case 2 involved a 55-year-old male with worsening cardiogenic shock which resulted in left ventricle Impella support. Due to decreased purge flow rates and concerns for clotting, argatroban was added to the purge solution. Both patients\u27 total argatroban regimens were monitored and adjusted by pharmacy, resulting in therapeutic anticoagulation without any major bleeding or thrombotic events. Subsequently, a protocol was designed and implemented. These case reports appear to demonstrate the safe and effective use of argatroban purge solutions for the necessary anticoagulation with an Impella device. Further studies are needed to confirm these results and determine the optimal dosing regimen

Systolic blood pressure and outcomes in patients on continuous flow LVAD support: An INTERMACS analysis

Purpose: High mean arterial pressures in continuous flow (cf) LVAD patients are associated with increased stroke and pump thrombosis risks. Optimal thresholds for systolic blood pressure are unknown. Methods: Systolic blood pressure (SBP) measurements in operative survivors of cfLVAD implant were obtained from the INTERMACS registry at 3, 6, and 12 months after implant. Survival was estimated with Kaplan-Meier methods and Cox Hazard Ratios [95% CI] for 1 year mortality were calculated. Results: SBPs were available in 7738 operative survivors at 3 and 6 months. The mean±std SBPs at discharge, 3, 6, and 12 months were 91.8±14.9, 98.9±16.1, 100.3±16.4, and 101.0±16.3 mmHg. Patients with an SBP \u3c 80 at 3 months were more likely to be INTERMACS 1 or 2, Bridge to transplant, and less likely to be African American. Survival was worse in those with low systolic blood pressure (table, p\u3c 0.001). Compared with having an SBP \u3e 100 at 3 months, SBPs \u3c 80 (HR 2.0 [1.6-2.4]) and 81-100 (HR 1.2 [1.1-1.4]) were associated with increased 1-year mortality. Controlling for age, race, sex, axial-flow configuration, preoperative albumin, preoperative creatinine, INTERMACS profile, 1Y mortality was still higher with SBP \u3c 80 (HR 2.0 [1.6-2.5]) and SBP 81-100 (HR 1.2 [1.02-1.4], p= 0.03) vs. an SBP \u3e 100 mmHg. Conclusion: Lower SBP after cfLVAD is independently associated with worse survival. This raises concern that excessive SBP control may be harmful in these patients. Dedicated trials to determine optimal BP targets are. warranted (Table presented)

Systolic blood pressure and outcomes in patients on continuous flow LVAD support: An INTERMACS analysis

Purpose: High mean arterial pressures in continuous flow(cf) LVAD patients are associated with increased stroke and pump thrombosis risks. Optimal thresholds for systolicblood pressure are unknown. Methods: Systolic bloodpressure (SBP) measurements in operative survivors of cfLVAD implant were obtained from the INTERMACS registry at 3, 6, and 12 months after implant. Survival was estimated with Kaplan-Meier methods and Cox Hazard Ratios [95% CI] for 1 year mortality were calculated. Results: SBPs were available in 7738 operative survivors at 3 and 6 months. The mean±std SBPs at discharge, 3, 6, and 12 months were 91.8±14.9, 98.9±16.1, 100.3±16.4, and 101.0±16.3 mmHg. Patients with an SBP \u3c 80 at 3 months were more likely to be INTERMACS 1 or 2, Bridge to transplant, and less likely to be African American. Survival was worse in those with low systolic blood pressure (table, p\u3c 0.001). Compared with having an SBP \u3e 100 at 3 months, SBPs \u3c 80 (HR 2.0 [1.6-2.4]) and 81-100 (HR 1.2 [1.1-1.4]) were associated with increased 1-year mortality. Controlling for age, race, sex, axial-flowconfiguration, preoperative albumin, preoperative creatinine, INTERMACS profile, 1Y mortality was still higher with SBP \u3c 80 (HR 2.0 [1.6-2.5]) and SBP 81-100 (HR 1.2 [1.02-1.4], p= 0.03) vs. an SBP \u3e 100 mmHg. Conclusion: Lower SBP after cfLVAD is independently associated with worse survival. This raises concern that excessive SBP control may be harmful in these patients. Dedicated trials to determine optimal BP targets are. warranted (Table presented)

Ventricular Assist Device Patient Phenotypes: What Attributes Describe Long Term Survival?

Purpose: Presently, 50% of patients on LVAD support are alive on therapy at 5 years. While preoperative (preop) variables can predict short term (ST) survival, correlates of long term (LT) survival remain poorly characterized. Using Intermacs-STS, we aim to identify preop and postoperative correlates of LT survival. Methods: Patients (n=16474) undergoing LVAD implant (2012-18) in Intermacs-STS were categorized as ST (survival ≤1 year postoperative, n=7483), mid-term (MT, 1-3 years, n=5976) and LT (\u3e3 years, n=3015) survivors. Pre-implant characteristics and events during support were compared between the three groups to identify mortality correlates. Results: Compared with patients dying in the ST, LT survivors were more likely to be younger, not listed for transplant, with higher BSA and VAS scores and several lower risk preop characteristics but differences between MT and LT survivors were not clinically significant (table). On multi-variable analysis, patients suffering post-LVAD stroke (HR 1.42, image), any major infection (HR 1.13), pump related infection (HR 1.19), and/or device malfunction (HR=1.22) (all p\u3c0.001) were less likely to live \u3e1 year, as were patients with a history of pulmonary disease (HR 1.19, 0.01), cancer (HR 1.26, p=0.01), CABG (HR 1.24, p\u3c0.001), hepatitis (HR 1.54, p=0.002) and active smoking (1.44, p \u3c0.001). Conclusion: The preop clinical features of ST and LT survivors vary significantly. Preop characteristics mainly select out early deaths, failing to accurately characterize survival after 1 year. LT survival is heavily influenced by device complications and pre-existing medical co-morbidities

Heart Rate and V˙O2 Concordance in Continuous-Flow Left Ventricular Assist Devices

UNLABELLED: The American College of Sports Medicine currently recommends the HR reserve (HRR) method to guide exercise in individuals who have heart failure with reduced ejection fraction. This recommendation is based on the known association between %HRR and percentage of V˙O2 reserve (%V˙O2R) in this population. However, to our knowledge, no studies exist regarding this relation in individuals with a left ventricular assist device (LVAD). PURPOSE: This article aimed to describe the relation between V˙O2 and surrogate markers of exercise intensity among patients with LVAD. METHODS: Patients with continuous-flow LVAD (n = 24, seven females) completed a symptom-limited graded exercise test on a treadmill. HR and V˙O2 were measured continuously and averaged every 20 s. Regression equations were determined using a generalized estimating equation to predict %V˙O2R from %HRR, Borg RPE, and LVAD flow, overall and stratified by presence of pacing. RESULTS: Although the association between %HRR and %V˙O2R was good (R = 0.75), the slope and y-intercept for %HRR versus %V˙O2R was different from the line of identity (P = 0.002). However, when paced subjects were excluded (n = 8) from the analysis, there was no significant difference between the slope and y-intercept (= 0.036 + 0.937 × %HRR; SEE, 2%; P = 0.052). RPE showed a strong association with %V˙O2R (R = 0.84), whereas LVAD flow showed a weak (albeit statistically significant) association (R = 0.05). Both had slopes and y-intercepts that were different from the line of identity (P \u3c 0.05). CONCLUSIONS: In patients with LVAD who are not paced during exercise, the use of %HRR is a good predictor of %V˙O2R. However, for patients in this population who are also paced during exercise, RPE is a suitable surrogate measure of exercise intensity