18 research outputs found

    Development of a Novel Echocardiography Ramp Test for Speed Optimization and Diagnosis of Device Thrombosis in Continuous-Flow Left Ventricular Assist Devices The Columbia Ramp Study

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    ObjectivesThis study sought to develop a novel approach to optimizing continuous-flow left ventricular assist device (CF-LVAD) function and diagnosing device malfunctions.BackgroundIn CF-LVAD patients, the dynamic interaction of device speed, left and right ventricular decompression, and valve function can be assessed during an echocardiography-monitored speed ramp test.MethodsWe devised a unique ramp test protocol to be routinely used at the time of discharge for speed optimization and/or if device malfunction was suspected. The patient's left ventricular end-diastolic dimension, frequency of aortic valve opening, valvular insufficiency, blood pressure, and CF-LVAD parameters were recorded in increments of 400 rpm from 8,000 rpm to 12,000 rpm. The results of the speed designations were plotted, and linear function slopes for left ventricular end-diastolic dimension, pulsatility index, and power were calculated.ResultsFifty-two ramp tests for 39 patients were prospectively collected and analyzed. Twenty-eight ramp tests were performed for speed optimization, and speed was changed in 17 (61%) with a mean absolute value adjustment of 424 ± 211 rpm. Seventeen patients had ramp tests performed for suspected device thrombosis, and 10 tests were suspicious for device thrombosis; these patients were then treated with intensified anticoagulation and/or device exchange/emergent transplantation. Device thrombosis was confirmed in 8 of 10 cases at the time of emergent device exchange or transplantation. All patients with device thrombosis, but none of the remaining patients had a left ventricular end-diastolic dimension slope >−0.16.ConclusionsRamp tests facilitate optimal speed changes and device malfunction detection and may be used to monitor the effects of therapeutic interventions and need for surgical intervention in CF-LVAD patients

    Hemodynamic Effects of Mechanical Circulatory Support Devices in Ventricular Septal Defect

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    BACKGROUND: Ventricular septal defect (VSD) is a lethal complication of acute myocardial infarction (AMI) and is often associated with cardiogenic shock. The optimal form of percutaneous mechanical circulatory support (MCS) for AMI-VSD is unknown. METHODS AND RESULTS: We used a previously validated cardiovascular model to simulate AMI-VSD with parameters adjusted to replicate average hemodynamics reported in the literature, including a pulmonary-to-systemic blood flow ratio of 3.0. We then predicted effects of different types of percutaneous MCS (including intra-aortic balloon pumping, Impella, TandemHeart, and extracorporeal membrane oxygenation) on pressures and flows throughout the cardiovascular system. The simulation replicated all major hemodynamic parameters reported in the literature with AMI-VSD. Inotropes and vasopressors worsened left-to-right shunting, whereas vasodilators decreased shunting at the expense of worsening hypotension. All MCS devices increased forward blood flow and arterial pressure but other effects varied among devices. Impella 5.0 provided the greatest degree of pulmonary capillary wedge pressure reductions and decreased left-to-right shunting. Extracorporeal membrane oxygenation worsened pulmonary capillary wedge pressure and shunting, which could be improved by adding Impella or passive left ventricular vent. Pulmonary-to-systemic blood flow ratio could not be reduced below 2.0, and pulmonary flows remained high with all forms of MCS. CONCLUSIONS: Although no form of percutaneous MCS normalized hemodynamics in AMI-VSD, pulmonary capillary wedge pressure and shunting were worsened by extracorporeal membrane oxygenation and improved by Impella. Accordingly, based on hemodynamics alone, Impella provides the optimal form of support in AMI-VSD. However, other factors, including team experience, device availability, potential for tissue ingestion, and clinical characteristics, need to be considered when choosing a percutaneous MCS device for AMI-VSD

    Pulmonary Artery Catheter Use and Risk of In-Hospital Death in Heart Failure Cardiogenic Shock

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    BACKGROUND: Pulmonary artery catheters (PACs) are increasingly used to guide management decisions in cardiogenic shock (CS). OBJECTIVES: The goal of this study was to determine if PAC use was associated with a lower risk of in-hospital mortality in CS due to acute heart failure (HF-CS). METHODS: Multicenter, retrospective, observational study of CS patients hospitalized between 2019-2021 at 15 US hospitals participating in the Cardiogenic Shock Working Group registry. The primary endpoint was in-hospital mortality. Inverse probability of treatment-weighted logistic regression models were used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CI), accounting for multiple variables at admission. The association between timing of PAC placement and in-hospital death was also analyzed. RESULTS: A total of 1055 HF-CS patients were included of whom 834 (79%) received a PAC during their hospitalization. In-hospital mortality risk for the cohort was 24.7% (n=261). PAC use was associated with lower adjusted in-hospital mortality risk (22.2% vs. 29.8%, OR 0.68, 95% CI 0.50-0.94). Similar associations were found across SCAI stages of shock, both at admission and at maximum SCAI stage during hospitalization. Early PAC use (≤ 6 hours of admission) was observed in 220 (26%) PAC recipients and associated with a lower adjusted risk of in-hospital mortality compared to delayed (≥ 48 hours) or no PAC use (17.3% vs. 27.7%, OR 0.54, 95% CI 0.37-0.81). CONCLUSIONS: This observational study supports PAC use, as it was associated with decreased in-hospital mortality in HF-CS, especially if performed within 6 hours of hospital admission. CONDENSED ABSTRACT: An observational study from the Cardiogenic Shock Working Group registry of 1,055 patients with heart failure related cardiogenic shock showed that pulmonary artery catheter (PAC) use was associated with lower adjusted in-hospital mortality risk (22.2% vs. 29.8%, OR 0.68, 95% CI 0.50-0.94) compared to outcomes in patients managed without PAC. Early PAC use (≤ 6 hours of admission) was associated with a lower adjusted risk of in-hospital mortality compared to delayed (≥ 48 hours) or no PAC use (17.3% vs. 27.7%, OR 0.54, 95% CI 0.37-0.81)

    Gut microbial diversity, inflammation, and oxidative stress are associated with tacrolimus dosing requirements early after heart transplantation.

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    IntroductionEffective tacrolimus (TAC) dosing is hampered by complex pharmacokinetics and significant patient variability. The gut microbiome, a key mediator of endotoxemia, inflammation and oxidative stress in advanced heart failure (HF) patients, is a possible contributor to interindividual variations in drug efficacy. The effect of alterations in the gut microbiome on TAC dosing requirements after heart transplant (HT) has not been explored.MethodsWe enrolled 24 patients (mean age = 55.8 ±2.3 years) within 3 months post-HT. Biomarkers of endotoxemia ((lipopolysaccharide (LPS)), inflammation (tumor necrosis factor-α (TNF-α)) and oxidative stress (8,12-iso-Isoprostane F-2alpha-VI) were measured in 16 blood samples. 22 stool samples were analyzed using 16S rRNA sequencing. TAC dose and serum trough level were measured at the time of stool and blood collection. TAC doses were reported in mg/kg/day and as level-to-dose (L/D) ratio, and categorized as ≤ vs. > median.ResultsThe median TAC dose was 0.1 mg/kg/day and L/D ratio was 100.01. Above the median daily weight-based TAC dose was associated with higher gut microbial alpha diversity (p = 0.03); similarly, TNF-α and 8,12-iso-Isoprostane F-2alpha-VI levels were lower and LPS levels were higher in the above median TAC group, although these findings were only marginally statistically significant and dependent on BMI adjustment. We observed n = 37 taxa to be significantly enriched among patients with > median TAC dose (all FDRConclusionsOur pilot study observed gut microbial alpha diversity to be increased while inflammation and oxidative stress were reduced among patients requiring higher TAC doses early after HT
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