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Abstract Aims It is unclear whether activated partial thromboplastin time (aPTT) or anti‐Xa is more accurate for monitoring heparin anticoagulation in mechanical circulatory support (MCS) patients. This study investigates the relationship between aPTT and anti‐Xa in MCS patients and identifies predictors of discordance. Methods and results aPTT and anti‐Xa were simultaneously measured in a prospective cohort of MCS patients receiving unfractionated heparin at a tertiary academic medical centre. Therapeutic aPTT and anti‐Xa levels were 60–100 s and 0.3–0.7 IU/mL, respectively, and concordance was defined as both levels being subtherapeutic, therapeutic, or supratherapeutic. To identify predictors of discordance, both a machine learning random forest model and a multivariate regression model were applied to patient demographics, device type, and 14 laboratory variables; 23 001 pairs of simultaneously measured aPTT/anti‐Xa were collected from 699 MCS patients. aPTT and anti‐Xa were concordant in 35.5% of paired observations and discordant in 64.5% (aPTT > antiXa 61.5%; aPTT antiXa) was associated with high INR, eGFR, and total bilirubin, as well as low platelets, haemoglobin, pre‐albumin, white blood cell count, and haptoglobin. Total artificial heart and durable ventricular assist devices were more likely to be associated with aPTT > anti‐Xa than temporary MCS devices. Conclusions aPTT and anti‐Xa were frequently discordant in MCS patients receiving heparin anticoagulation. Clinical conditions common in MCS patients such as concurrent warfarin use, malnutrition, haemolysis, and thrombocytopenia, as well as durable type of MCS devices were associated with a high aPTT relative to anti‐Xa.

Abstract Aims Continuous‐flow left ventricular assist devices (LVADs) as destination therapy (DT) are a recommended treatment by National Institute for Health and Care Excellence England for end‐stage heart failure patients ineligible for cardiac transplantation. Despite the fact that DT is frequently used as an LVAD indication across other major European countries and the United States, with consistent improvements in quality‐of‐life and longevity, National Health Service (NHS) England does not currently fund DT, mainly due to concerns over cost‐effectiveness. On the basis of the recently published ENDURANCE Supplemental Trial studying DT patients, we assessed for the first time the cost‐effectiveness of DT LVADs compared with medical management (MM) in the NHS England. Methods and results We developed a Markov multiple‐state economic model using NHS cost data. LVAD survival and adverse event rates were derived from the ENDURANCE Supplemental Trial. MM survival was based on Seattle Heart Failure Model estimates in the absence of contemporary clinical trials for this population. Incremental cost‐effectiveness ratios (ICERs) were calculated over a lifetime horizon. A discount rate of 3.5% per year was applied to costs and benefits. Deterministic ICER was £46 207 per quality‐adjusted life year (QALY). Costs and utilities were £204 022 and 3.27 QALYs for the LVAD arm vs. £77 790 and 0.54 QALYs for the MM arm. Sensitivity analyses confirmed robustness of the primary analysis. Conclusions The implantation of the HeartWare™ HVAD™ System in patients ineligible for cardiac transplantation as DT is a cost‐effective therapy in the NHS England healthcare system under the end‐of‐life willingness‐to‐pay threshold of £50 000/QALY, which applies for VAD patients.

Abstract Aims Optimal blood pressure (BP) control is imperative to reduce complications, especially strokes, in continuous flow ventricular assist device (VAD) patients. Doppler BP has been shown to be an accurate and reliable non‐invasive BP measurement method in HeartMate II and HVAD patients. We examined whether Doppler BP is also accurate in patients with the HeartMate 3 VAD. Methods and results In a prospective, longitudinal cohort of HeartMate 3 patients, arterial line BP and simultaneously measured Doppler opening pressure were obtained. Correlation and agreement between Doppler opening pressure and arterial line mean arterial pressure (MAP) versus systolic blood pressure (SBP) were analysed, as well as the effect of pulse pressure on the accuracy of Doppler opening pressure. A total of 589 pairs of simultaneous Doppler opening pressure and arterial line pressure readings were obtained in 43 patients. Doppler opening pressure had good correlation with intra‐arterial MAP (r = 0.754) and more closely approximated MAP than SBP (mean error 2.0 vs. −8.6 mmHg). Pulse pressure did not have a clinically significant impact on the accuracy of the Doppler BP method. These results in HeartMate 3 patients are very similar to previous results in HeartMate II and HVAD patients. Conclusions Doppler BP method should be the default non‐invasive BP measurement method in continuous flow VAD patients including patients implanted with the HeartMate 3.

Abstract Aims Despite advances in coronary reperfusion and percutaneous mechanical circulatory support, mortality among patients presenting with cardiogenic shock (CS) remains unacceptably high. Clinical trials and risk stratification tools have largely focused on acute CS, particularly secondary to acute coronary syndrome. Considerably less is understood about CS in the setting of acute decompensation in patients with chronic heart failure (HF). We sought to compare outcomes between patients with acute CS and patients with acute on chronic decompensated HF presenting with laboratory and haemodynamic features consistent with CS. Methods and results Sequential patients admitted with CS at a single quaternary centre between January 2014 and August 2017 were identified. Acute on chronic CS was defined by having a prior diagnosis of HF. Initial haemodynamic and laboratory data were collected for analysis. The primary outcome was in‐hospital mortality. Secondary outcomes were use of temporary mechanical circulatory support, durable ventricular assist device implantation, total artificial heart implantation, or heart transplantation. Comparison of continuous variables was performed using Student's t‐test. For categorical variables, the χ2 statistic was used. A total of 235 patients were identified: 51 patients (32.8%) had acute CS, and 184 patients (64.3%) had acute decompensation of chronic HF with no differences in age (52 ± 22 vs. 55 ± 14 years, P = 0.28) or gender (26% vs. 23%, P = 0.75) between the two groups. Patients with acute CS were more likely to suffer in‐hospital death (31.4% vs. 9.8%, P

Abstract Aims Accurate blood pressure (BP) measurement in continuous‐flow ventricular assist device (CF‐VAD) patients is imperative to reduce stroke risk. This study assesses the accuracy of the Doppler opening pressure method compared with the gold standard arterial line method in CF‐VAD patients. Methods and results In a longitudinal cohort of HeartMate II and HVAD patients, arterial line BP and simultaneously measured Doppler opening pressure were obtained. Overall correlation, agreement between Doppler opening pressure and arterial line mean vs. systolic pressure, and the effect of arterial pulsatility on the accuracy of Doppler opening pressure were analysed. A total of 1933 pairs of Doppler opening pressure and arterial line pressure readings within 1 min of each other were identified in 154 patients (20% women, mean age 55 ± 15, 50% HeartMate II and 50% HVAD). Doppler opening pressure had good correlation with invasive mean arterial pressure (r = 0.742, P