ASAIO Journal最新文献

A critical factor in thrombus formation during venoarterial extracorporeal membrane oxygenation (VA ECMO) is prothrombotic flow dynamics generated by the drainage cannula's design. This study aimed to create and evaluate a novel drainage cannula design which optimized blood flow dynamics to reduce thrombus formation. Computational fluid dynamics (CFD) was used to iteratively vary drainage cannula design parameters such as inner wall shape and side hole shape. The final novel design was then placed in an ex vivo blood circulation loop, and compared against a Bio-Medicus cannula (n = 6, each). Clot volume, hemolysis, and other parameters were measured to assess thrombus formation markers. The novel design consisted of a parabolic inner wall profile with closely spaced side holes angled at 30º to align with flow. When tested in the ex vivo loop, the novel design resulted in lower instances (two vs . four) and volumes of clot in the cannula (360.5 ± 254.8 vs . 1258.0 ± 651.7 µl) when compared to the Bio-Medicus cannula. Results from tests assessing hemolysis, platelet activation, and other thrombotic markers revealed a noninferior relationship between the novel and Bio-Medicus designs. Future work will explore the clinical applicability of these findings.

Bleeding complications have emerged as major causes of morbidity and mortality in patients with implantable left ventricular assist devices (LVAD). We hypothesized that the hemodynamics after LVAD implantation may influence the occurrence of bleeding complications after LVAD implantation. We retrospectively evaluated 78 patients who underwent continuous-flow LVAD implantation and hemodynamic ramp test after LVAD implantation between July 2017 and July 2023 at Osaka University. The bleeding complication occurred in 13 patients. The rates of freedom from bleeding complications at 1, 3, and 5 years were 94%, 85%, and 74%. Gastrointestinal bleeding, nose bleeding, and intraperitoneal hemorrhage occurred in six, three, and two patients, respectively. Preoperative average brachial-ankle pulse wave velocity (baPWV) was positively associated with bleeding complication (1,276 ± 280 vs . 1,098 ± 190 cm/s p = 0.04). In the hemodynamic ramp test, systemic vascular resistance (SVR) in patients with bleeding complications was higher than that in patients without bleeding complications (SVR: 1,359 ± 341 vs. 1,150 ± 217 dyne sec/cm 5 , p = 0.01). High preoperative baPWV and high SVR in the hemodynamic ramp test were significantly associated with bleeding complications after LVAD implantation. Arteriosclerosis is a risk factor for bleeding complications after LVAD implantation.

The ingested pump inflow thrombus, although rare, is a potentially life-threatening complication of left ventricular assist devices. During the last years, the backwash maneuver is considered an alternative method to pump replacement for the treatment of inflow thrombosis, showing high success rate in selected patients with HeartWare HVAD devices. However, that was not the case in our present report, in which we detail the application of this method in two HeartMate3 patients with ingested pump inflow thrombus. Washing out the thrombus was not feasible in either case, possibly due to mechanical aspects of the inflow part of the HeartMate3 pump. As a result, we remain skeptical regarding the use of the method in HeartMate3 patients with inflow thrombosis.

Prior studies assessing the effects of Impella 5.5 support duration on posttransplant outcomes have been limited to single-center case reports and series. This study evaluates the impact of Impella 5.5 support duration on outcomes following heart transplantation using the United Network for Organ Sharing database. Adult heart transplant recipients who were directly bridged to primary isolated heart transplantation with Impella 5.5 were included. The cohort was stratified into two groups based on the duration of Impella support: less than or equal to 14 and greater than 14 days. The primary outcome was 90 day posttransplant survival. Propensity score matching was performed. Sub-analysis was conducted to evaluate the impact of greater than 30 days of Impella support on 90 day survival. Three hundred thirty-two recipients were analyzed. Of these, 212 recipients (63.9%) were directly bridged to heart transplantation with an Impella support duration of greater than 14 days. The two groups had comparable 90 day posttransplant survival and complication rates. The comparable posttransplant survival persisted in a propensity score-matched comparison. In the sub-analysis, Impella support duration of greater than or equal to 30 days did not adversely impact 90 day survival. This study demonstrates that extended duration of support with Impella 5.5 as a bridge to transplantation does not adversely impact posttransplant outcomes. Impella 5.5 is a safe and effective bridging modality to heart transplantation.

We sought to develop and validate a new risk stratification score for mortality for children supported with a ventricular assist device (VAD). This retrospective, multicenter study used data from patients undergoing VAD implantation between April 2018 and February 2023 at 44 participating institutions in the Advanced Cardiac Therapies Improving Outcomes (ACTION) network. Multivariable Cox proportional-hazards modeled mortality after VAD implantation. A total of 1,022 patients were enrolled. The 1 year mortality was 19% (95% confidence interval [CI]: 16-23). The multivariable model was used to build the ACTION VADs risk stratification score with four components: ventilation, advanced organ support (dialysis or ECMO), diagnosis, and size (weight ≤5 kg). One point is added for each risk factor. Based on the sum of the risk factors, patients were classified into four classes: class 0-green (4% mortality at 1 year), class 1-yellow (16% mortality at 1 year), class 2-orange (21% mortality at 1 year), and class 3 or higher-red (42% mortality at 1 year). The score performed well, with area under the curve (AUC) of 0.72 and excellent calibration. The ACTION VADs score for mortality can be calculated easily and offers risk stratification and prognostic information for pediatric VAD candidates. This is the first validated risk assessment tool for pediatric mechanical circulatory support.

Elevated pulmonary vascular resistance (PVR) is a risk factor for mortality after heart transplantation (HT), but whether this association differs for patients with and without left ventricular assist device (LVAD) support before HT is unknown. We analyzed adult first-time HT recipients from the United Network for Organ Sharing (UNOS) registry transplanted between 2010 and 2021. We quantified the association between PVR and the outcomes of 30 day graft failure and 1 year mortality using multivariable logistic regression, stratified by LVAD support status at the time of HT. Pulmonary vascular resistance was modeled using restricted cubic splines to identify clinically relevant risk thresholds. We also examined the association with 10 year survival using multivariable Cox proportional hazards regression. For PVR values less than approximately 2 WU, higher PVR was independently associated with a higher risk of early graft failure (odds ratio [OR] = 1.58, 95% CI: 1.06-2.36) and a higher risk of 1 year mortality (OR = 1.32, 95% CI: 1.10-1.59) among LVAD patients only (interaction p = 0.023 and 0.03, respectively). However, for patients surviving at least 1 year, PVR was not associated with long-term mortality among either subgroup. Whether more aggressive reduction of PVR among HT candidates supported with LVADs can mitigate these risks requires further study.

A proportion of patients still need mechanical circulatory support (MCS) during the transcatheter aortic valve replacement (TAVR) because of intraoperative hemodynamic instability. However, the outcomes of patients with different MCS type during TAVR are still controversial. A total of 538 patients who underwent TAVR procedure in four centers were included. The time-related outcomes and their predictors of patients who did not have MCS (MCS-, n = 498) were compared with those who underwent emergency MCS (eMCS+, n = 18) and prophylactic MCS (pMCS+, n = 22). We evaluated the association between different MCS groups and all-cause mortality using conditional landmark analysis with Cox regression. There was a significant increase in 30-day mortality in the eMCS+ group ( plog-rank < 0.001) and no significant difference in 31-day to 1-year mortality among the groups ( plog-rank = 0.789). A significant improvement in the left ventricular ejection fraction was observed in the pMCS+ group at 1 year after TAVR. Emergency MCS was independently associated with 30-day mortality, as well as 1-year mortality. Prophylactic MCS showed good clinical outcomes and might be considered for high-risk patients. Further studies are needed to investigate the predictors that lead to MCS usage and long-term mortality in TAVR patients with MCS.