Orthotist involvement in early gait rehabilitation after stroke: A cross-sectional survey of orthotists in the United Kingdom.

BACKGROUND: The role of the orthotist in early gait rehabilitation after stroke in the United Kingdom is currently poorly understood. OBJECTIVES: The objective of this study was to capture current opinion and practice of orthotists on their role in early stroke gait rehabilitation in the United Kingdom. METHODS: An anonymous web-based cross-sectional survey was developed and distributed to Health and Care Professions Council-registered orthotists by the mailing list of the British Association of Prosthetists and Orthotists professional body in the United Kingdom. Survey items were multiple-choice, Likert scale, or open-ended questions to explore the experiences and opinions of orthotists in early poststroke gait rehabilitation. RESULTS: Responses were received from 56 participants. Orthotists reported having regular contact with patients who had a stroke within their usual clinical caseload. Multidisciplinary care was not typical with 46% respondents "rarely" seeing patients who had a stroke in joint assessment with another clinician. Confidence in managing lower limb gait difficulties was high, with 89% of orthotists feeling able to recommend a lower limb orthotic treatment. Ninety-eight percent (n = 55) of respondents agreed that orthotic assessment should be an essential element of gait re-education after stroke; however, orthotists reported limited involvement within early stroke rehabilitation. CONCLUSION: UK orthotists surveyed in this study report that orthotic treatment is an important aspect of early gait rehabilitation after stroke. Respondents report barriers to multidisciplinary working, which may affect outcomes in this patient group.

Unconventional acoustic wave propagation transitions induced by resonant scatterers in the high-density limit.

Experiments on ultrasound propagation through a gel doped with resonant encapsulated microbubbles provided evidence for a discontinuous transition between wave propagation regimes at a critical excitation frequency. Such behavior is unlike that observed for soft materials doped with non-resonant air or through liquid foams, and disagrees with a simple mixture model for the effective sound speed. Here, we study the discontinuous transition by measuring the transition as a function of encapsulated microbubble volume fraction. The results show the transition always occurs in the strong-scattering limit (l/λ < 1, l and λ are the mean free path and wavelength, respectively), that at the critical frequency the effective phase velocity changes discontinuously to a constant value with increasing microbubble volume fraction, and the measured critical frequency shows a power law dependence on microbubble volume fraction. The results cannot be explained by multiple scattering theory, viscous effects, mode decoupling, or a critical density of states. It is hypothesized the transition depends upon the microbubble on-resonance effective properties, and we discuss the results within the context of percolation theory. The results shed light on the discontinuous transition's physics, and suggest soft materials can be engineered in this manner to achieve a broad range of physical properties with potential application in ultrasonic actuators and switches.

Left atrial to coronary sinus shunting for treatment of heart failure with mildly reduced or preserved ejection fraction: The ALT FLOW Early Feasibility Study 1-year results.

AIMS: Patients with heart failure and mildly reduced or preserved ejection fraction have limited therapeutic options. The ALT-FLOW Early Feasibility Study evaluated safety, haemodynamics and outcomes for the APTURE transcatheter shunt system, a novel left atrium to coronary sinus shunt in these patients. METHODS AND RESULTS: Safety and shunt implantation success was evaluated for all 116 enrolled patients. An analysis population of implanted patients with a left ventricular ejection fraction (LVEF) >40% (n = 95) was chosen to assess efficacy via paired comparison between baseline and follow-up haemodynamic (3 and 6 months), and echocardiographic, clinical and functional outcomes (6 months and 1 year). Health status and quality of life outcomes were assessed using the Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS). The primary safety endpoint, major adverse cardiac, cerebral, and renal events, and reintervention through 30 days, occurred in 3/116 patients (2.6%). All implanted shunts were patent at 1 year. In patients with LVEF >40%, the mean (95% confidence interval) reduction in exercise pulmonary capillary wedge pressure (PCWP) at 20 W was -5.7 (-8.6, -2.9) mmHg at 6 months (p < 0.001). At baseline, 8% had New York Heart Association class I-II status and improved to 68% at 1 year (p < 0.001). KCCQ-OSS at baseline was 39 (35, 43) and improved at 6 months and 1 year by 25 (20-30) and 27 (22-32) points, respectively (both p < 0.0001). No adverse changes in haemodynamic and echocardiographic indices of right heart function were observed at 1 year. Overall, the reduction in PCWP at 20 W and improvement in KCCQ-OSS in multiple subgroups were consistent with those observed for the entire population. CONCLUSIONS: In patients with heart failure and LVEF >40%, the APTURE shunt demonstrated an acceptable safety profile with significant sustained improvements in haemodynamic and patient-centred outcomes, underscoring the need for further evaluation of the APTURE shunt in a randomized trial.

Risk Factors for 1-Year Mortality After Heart Transplant in Obese Patients Bridged With an LVAD.

BACKGROUND: Heart transplantation is relatively contraindicated in morbidly obese patients because of increased morbidity and mortality. This study identified risk factors for post-heart transplantation mortality in obese patients with a left ventricular assist device (LVAD). METHODS: The United Network for Organ Sharing database was used to identify patients with a body mass index ≥35 kg/m2 who had a durable LVAD at the time of isolated heart transplantation between 2010 and 2021. The primary outcome was post-heart transplantation 1-year mortality. Multivariable Cox regression modeling was used to identify significant risk factors for 1-year mortality. Receiver-operating characteristic analyses were performed to identify optimal thresholds for continuous variables associated with the primary outcome. Patients were stratified by the number of risk factors, and Kaplan-Meier analysis was used to compare survival. RESULTS: A total of 1222 obese patients were bridged to heart transplantation with a durable LVAD. Six risk factors were identified as significantly associated with 1-year post-heart transplantation mortality: recipient age >62.5 years, body mass index >36.6 kg/m2, bilirubin level >0.95 mg/dL, cold ischemic time >3.7 hours, recipient-donor sex mismatch, and pretransplantation mechanical ventilation. The distribution of cumulative risk factors was as follows: 8.6% with 0, 30.6% with 1, 37.0% with 2, and 23.8% patients with ≥3 risk factors. The 1-year survival rate decreased significantly from 96.0% in those patients with 0 risk factors to 77.6% in those with 3 or more risk factors. CONCLUSIONS: These data provide a useful guide for risk stratification and patient selection in obese LVAD candidates being considered for heart transplantation.

A multicenter evaluation of the HeartMate 3 risk score.

BACKGROUND: The Heartmate 3 (HM3) risk score (HM3RS) was derived and validated internally from within the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 (MOMENTUM 3) trial population and provides 1- and 2-year mortality risk prediction for patients in those before HM3 left ventricular assist device (LVAD) implantation. We aimed to evaluate the HM3RS in nontrial unselected patients, including those not meeting inclusion criteria for MOMENTUM 3 trial enrollment. METHODS: Patients who underwent HM3 LVAD implant at 1 of 7 US centers between 2017 and 2021, with at least 1-year follow-up, were included in this analysis. Patients were retrospectively assessed for their eligibility for the MOMENTUM 3 trial based on study inclusion and exclusion criteria. HM3RS risk discrimination was evaluated using time-dependent receiver operating characteristic curve analysis for 1-year mortality for all patients and further stratified by MOMENTUM 3 trial eligibility. Kaplan-Meier curves were constructed using the HM3RS-based risk categories. RESULTS: Of 521 patients included in the analysis, 266 (51.1%) would have met enrollment criteria for MOMENTUM 3. The 1- and 2-year survival for the total cohort was 85% and 81%, respectively. There was no statistically significant difference in survival between those who met and did not meet enrollment criteria at 1 (87% vs 83%; p = 0.21) and 2 years postimplant (80% vs 78%; p = 0.39). For the total cohort, HM3RS predicted 1-year survival with an area under the curve (AUC) of 0.63 (95% confidence interval [CI]: 0.57-0.69, p < 0.001). HM3RS performed better in the subset of patients meeting enrollment criteria: AUC 0.69 (95% CI:0.61-0.77, p < 0.001) compared to the subset that did not: AUC 0.58 (95% CI: 0.49-0.66, p = 0.078). CONCLUSIONS: In this real-world evidence, multicenter cohort, 1- and 2-year survival after commercial HM3 LVAD implant was excellent, regardless of trial eligibility. The HM3RS provided adequate risk discrimination in "trial-like" patients, but predictive value was reduced in patients who did not meet trial criteria.

Ventricular assist devices and sleep-disordered breathing-A mechanical heart stimulating a sleepy brain.

Sleep-disordered breathing, including obstructive sleep apnea (OSA) and central sleep apnea (CSA), is common in severe heart failure (HF) patients. There is limited data on the effect of left ventricular assist devices (LVAD) on sleep apnea. We performed a retrospective review of 350 durable LVAD patients and found 5 with a history of pre- and post-LVAD sleep studies. All five patients had OSA, and three had concomitant CSA. We observed reduced apnea-hypopnea index following LVAD placement. This was due to a near abolishment of CSA in three mixed sleep apnea patients-as seen by a central apnea index improvement from an average of 25.9 ± 13.1 to 1.4 ± 2.5 events per hour (p = 0.063). LVAD placement was associated with an increase in thermodilution cardiac output from 2.7 ± 0.6 to 4.1 ± 1.1 L/min (p = 0.014). These findings support chemoreception physiology seen in patients with poor circulation and the effect of restoring this circulation with LVAD support.

Right Ventricular Contractility and Pulmonary Arterial Coupling After Less Invasive Left Ventricular Assist Device Implantation.

Right ventricular failure contributes significantly to morbidity and mortality after left ventricular assist device implantation. Recent data suggest a less invasive strategy (LIS) via thoracotomy may be associated with less right ventricular failure than conventional median sternotomy (CMS). However, the impact of these approaches on load-independent right ventricular (RV) contractility and RV-pulmonary arterial (RV-PA) coupling remains uncertain. We hypothesized that the LIS approach would be associated with preserved RV contractility and improved RV-PA coupling compared with CMS. We performed a retrospective study of patients who underwent durable, centrifugal left ventricular assist device implantation and had paired hemodynamic assessments before and after implantation. RV contractility (end-systolic elastance [Ees]), RV afterload (pulmonary effective arterial elastance [Ea]), and RV-PA coupling (Ees/Ea) were determined using digitized RV pressure waveforms. Forty-two CMS and 21 LIS patients were identified. Preimplant measures of Ees, Ea, and Ees/Ea were similar between groups. After implantation, Ees declined significantly in the CMS group (0.60-0.40, p = 0.008) but not in the LIS group (0.67-0.58, p = 0.28). Coupling (Ees/Ea) was unchanged in CMS group (0.54-0.59, p = 0.80) but improved significantly in the LIS group (0.58-0.71, p = 0.008). LIS implantation techniques may better preserve RV contractility and improve RV-PA coupling compared with CMS.

Cardio-Obstetric Shock: Mechanical Circulatory Support as a Bridge to Pregnancy Viability.

Cardiogenic shock in pregnancy is rare but is associated with significant morbidity and mortality. Timely recognition with multidisciplinary management is necessary for optimal maternal and fetal outcomes. Here we present a case of cardiogenic shock in the antepartum period managed with mechanical circulatory support as a bridge to pregnancy viability.

SARS-CoV-2 Infection Precipitating VT Storm in Patients With Cardiac Sarcoidosis.

The authors describe 3 patients presenting with cardiac sarcoidosis (CS) flare and ventricular tachycardia (VT) storm following infection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19. COVID-19-related cardiac manifestations can vary and include arrythmias, myocarditis, and exacerbation of underlying cardiovascular disease. The exact mechanism of myocardial involvement is not clear but may include abnormal host immune response and direct myocardial injury, thereby predisposing to enhanced arrhythmic risk. Arrhythmias account for 20% of COVID-19-related complications with ventricular arrythmias occurring in 5.9% of cases. Further studies are needed to better understand mechanisms underlying the intersection between COVID-19 infection and inflammatory cardiomyopathies.

How to Select Patients for Left Ventricular Assist Devices? A Guide for Clinical Practice.

In recent years, a significant improvement in left ventricular assist device (LVAD) technology has occurred, and the continuous-flow devices currently used can last more than 10 years in a patient. Current studies report that the 5-year survival rate after LVAD implantation approaches that after a heart transplant. However, the outcome is influenced by the correct selection of the patients, as well as the choice of the optimal time for implantation. This review summarizes the indications, the red flags for prompt initiation of LVAD evaluation, and the principles for appropriate patient screening.

Standardization of the Right Heart Catheterization and the Emerging Role of Advanced Hemodynamics in Heart Failure.

The accurate assessment of hemodynamics is paramount to providing timely and efficacious care for patients presenting in cardiogenic shock. Recently, the regular use of the pulmonary artery catheter in cardiogenic shock has had a resurgence with emerging data indicating improved survival in the modern era. Optimal multidisciplinary management of advanced heart failure and cardiogenic shock relies on our ability to effectively communicate and understand the complete hemodynamic assessment. Standardization of data acquisition and a renewed focus on the physiological processes, and thresholds driving disease progression, including the coupling ratio and myocardial reserve, are needed to fully understand and interpret the hemodynamic assessment. This State-of-the-Art review discusses best practices in the cardiac catheterization laboratory as well as emerging data on the prognostic role of emerging advanced hemodynamic parameters.

Is it time to stop living in a HeartMate II world?

Despite improving outcomes with modern pump technology, left ventricular assist device (LVAD) utilization for patients with end-stage heart failure (HF) has declined significantly in the preceding half-decade. Here, we examine this trend, noting an inherent contradiction in the declining utilization of an improving therapeutic option. We propose a series of provocative questions as a "call to action" for the field of advanced HF to consider both scientifically and clinically, focusing on our evaluation parameters for LVAD candidacy, our approach to dichotomous LVAD vs transplant decisions, and our current management paradigms. We conclude that modernization in these areas to match the advantages of modern pump technology is required to best serve patients with advanced HF.

Impact of Donor Hemodynamics on Recipient Survival in Heart Transplantation.

BACKGROUND: Heart transplantation is the gold-standard therapy for end-stage heart failure, but rates of donor-heart use remain low due to various factors that are often not evidence based. The impact of donor hemodynamics obtained via right-heart catheterization on recipient survival remains unclear. METHODS: The United Network for Organ Sharing registry was used to identify donors and recipients from September 1999-December 2019. Donor hemodynamics data were obtained and analyzed using univariate and multivariable logistical regression, with the primary endpoints being 1- and 5-year post-transplant survival. RESULTS: Of the 85,333 donors who consented to heart transplantation during the study period, 6573 (7.7%) underwent right-heart catheterization, of whom 5531 eventually underwent procurement and transplantation. Donors were more likely to undergo right-heart catheterization if they had high-risk criteria. Recipients who had donor hemodynamic assessment had 1- and 5-year survival rates similar to those without donor hemodynamic assessment (87% vs 86%, 1 year). Abnormal hemodynamics were common in donor hearts but did not impact recipient survival rates, even when risk-adjusted in multivariable analysis. CONCLUSIONS: Donors with abnormal hemodynamics may represent an opportunity to expand the pool of viable donor hearts.