ASAIO Journal最新文献

HeartMate III (HM3) pump failure due to intrapump obstruction from biodebris or thrombosis is an uncommon but life-threatening condition. Here, we describe a case of HM3 failure from biodebris occluding the inflow cannula and pump interior 11 months after initial implant.

Mechanical circulatory support (MCS) devices are standard therapy for advanced heart failure, but modern systems lack standardized methods for setting critical parameters such as rotational speed and flow rate. We developed an integrated model to support MCS parameter adjustment and provide continuous hemolysis and hemodynamic monitoring. The model combines lumped parameter modeling (LPM) and reduced order modeling (ROM) derived from high-resolution computational fluid dynamics of the device. Sensitivity analysis and Bayesian algorithms were used to ensure efficient model calibration and to identify and quantify the most influential parameters driving model outputs. Retrospective data from clinical use of the magnetically levitated centrifugal extracorporeal ventricular assist device MoyoAssist (magAssist, Suzhou, China) were analyzed. The model efficiently fit clinical data (n = 11) using five initial and two subsequent parameters. It provided key hemodynamic information such as left ventricular elastance, pressure-volume (P-V) loops, and hemolysis risk. The model revealed a relationship between rotational speed and cardiac index (CI), identifying a safe adjustment range with a total cardiac index (CI_total) >2.2 and native cardiac index (CI_heart) >0.25. This demonstrates feasibility for rapid P-V loop and ventricular elastance calculation after deployment, providing a basis for defining target CI values and recommending speed adjustments to optimize MCS use. https://links.lww.com/ASAIO/B889.

The ex situ heart perfusion technique is noninferior to the standard of care static cold preservation in heart transplantation. It has enabled the expansion of donor criteria and provides reconditioning or treatment as well as diagnostic approaches. Angiography during ex situ heart perfusion is anecdotal but may be useful to evaluating anatomy and somehow coronary physiology on the beating donor heart. The aim of this study was to assess the efficacy and safety of coronary investigation of the beating heart during normothermic ex situ heart perfusion using our institution's unique system. Five domestic adult pigs (90-95 kg, 1-1.5 years of age) were included in the study. After cardiectomy, the pig hearts were connected to the ex situ device, and ex situ angiography and intravascular ultrasound were performed. Cineangiographic images were obtained in different orientations by rotating the C-arm around the heart to find the best angiographic projections for the coronary arteries to be visualized. The results of our study support ex situ coronary arteries evaluation during the normothermic ex situ heart perfusion as a reliable, safe procedure that can be successfully carried out when necessary. The intravascular ultrasound can be used as an adjunctive technology for creating a full picture of the coronary arteries' anatomy.

Heart failure is a significant complication of chronic intravascular hemolysis, a condition characterized by red blood cells (RBCs) breakdown, leading to the release of acellular hemoglobin (Hb) and its oxidized form, methemoglobin (MetHb), into the bloodstream. Acellular Hb promotes nitric oxide (NO) scavenging, oxidative stress, inflammation, iron overload, and functional tissue impairment. This study investigates the direct impact of Hb and MetHb on cardiomyocyte function by assessing calcium transients, fractional shortening, and reactive oxygen species (ROS) formation. The study also evaluated the effects of polymerized Hb, NO scavenging, and antioxidant therapy using N-acetylcysteine (NAC) on cardiomyocyte contractility. Our results show that acellular Hb and MetHb impair cardiomyocyte function by prolonging calcium transient half-life, reducing contractility, and increasing ROS production. Polymerization of Hb and antioxidant supplementation offered partial protection but did not fully mitigate these effects. Inhibiting NO synthase did not increase Hb toxicity, indicating that NO scavenging is not the sole toxicity pathway. These findings demonstrate that Hb-induced cardiomyocyte dysfunction involves a multifactorial mechanism, including NO scavenging, oxidative stress, and disrupted calcium dynamics. Although Hb polymerization and antioxidants offer limited protection, novel multi-target strategies are essential to address Hb toxicity in hemolytic disorders and the use of Hb-based oxygen carriers.

The drainage cannula in a venoarterial extracorporeal membrane oxygenation (VA ECMO) circuit transfers venous blood from the patient to a pump. However, drainage cannulas are prone to thrombosis, leading to significant morbidity in patients. Therefore, this study aimed to evaluate the effects of cannula size, design, and flow rate on flow dynamics and risk of flow-induced thrombosis in different patient geometries using computational fluid dynamics (CFD). Four cannulas (21 Fr and 23 Fr Bio-Medicus and Maquet models) were modeled in three patient-specific venous vasculatures. These were simulated at 2, 3, 4, and 5 L/min drainage flow rates (N = 48 simulations). To assess potential thrombosis risk, a platelet activation model was implemented along with measurement of prothrombotic flow markers. Increasing drainage flow rates worsened washout rates and increased blood residence times and platelet activation rates. The 21 Fr Bio-Medicus cannula had greater activated platelet distributions and higher tip velocities than the 21 Fr Maquet model. Lastly, patient geometry altered blood residence times, washout rates, and activated platelet distributions, but not flow within the cannulas themselves. These findings will be beneficial for clinicians in their cannula selection and cannulation strategy for VA ECMO, as well as engineers in the development of future drainage cannulas.

Extracorporeal cardiopulmonary resuscitation (ECPR) requires advanced skills for induction and management. This study evaluated whether the outcomes of ECPR differ by institutional volume. Using the Japanese Association for Acute Medicine-Out-of-Hospital Cardiac Arrest (JAAM-OHCA) registry, we analyzed adult patients (aged ≥18 years) who received ECPR between 2014 and 2020, focusing on 30 day in-hospital survival and favorable neurologic prognosis at 30 days defined as Cerebral Performance Category (CPC) 1-2. Facilities were categorized into tertiles by annual ECPR volume. Multivariable logistic regression examined outcomes across low (≤4.7 cases/year), medium (4.8-7.8 cases/year), and high (≥7.9 cases/year) volume groups. A total of 1,759 patients from 83 centers were included, with an overall 30 day survival of 21.1% and CPC 1-2 rate of 10.1%. We observed no statistically significant differences in the respective rates of 30 day survival and neurologic outcomes in the medium ECPR volume group (adjusted odds ratios 1.09 [95% confidence interval {CI}, 0.82-1.47] and 0.85 [0.56-1.26]) and higher ECPR volume group (adjusted odds ratios 1.27 [95% CI, 0.95-1.70] and 1.11 [0.75-1.63]) compared with the lower ECPR volume group. These findings suggest that ECPR outcomes for out-of-hospital cardiac arrest are not significantly affected by institutional ECPR volume.