Inglis, Sara S.

Introduction: The Impella 5.5 is frequently employed to provide temporary mechanical circulatory support as bridge to recovery or durable therapy. Optimization of device management relies on understanding ventricular pressure-volume (PV) relationships. Aim: The aim of this study was to evaluate the biventricular (BiV) relationship with PV loop assessment during Impella 5.5 support in non-myopathic ventricles. Methods: Six domestic Yorkshire Pigs were used for this study. The Impella 5.5 (J&J MedTech, NJ) was inserted percutaneously under ultrasound and fluoroscopic guidance through either the carotid artery or aortic arch, using a 26Fr DrySeal Sheath (Gore, AZ). BiV PV loop conductance catheters (Sigma-M, CD Leycom, Hengelo, The Netherlands) were inserted via femoral venous access. The LV PV loop catheter is positioned via transeptal puncture and with intracardiac echocardiogram guidance. BiV PV loops are generated for each level of Impella 5.5 support. Results: With increasing levels of Impella 5.5 support, left ventricular (LV) PV loops shifted increasingly to the left and right ventricular (RV) loops to the right. Accordingly, LV end-diastolic volume (EDV) decreased (110±4 ml to 90±8 ml; p<0.001) and RV EDV increased (121±7 ml to 147±13 ml; p<0.001), from baseline to P9. Native LV systolic function decreased with increasing Impella 5.5 support, as demonstrated by a reduction in stroke volume (SV) (56±5 ml to 49±5 ml; p<0.001), cardiac output (CO) (3.4±0.8 ml/min to 2.0±0.3 ml/min; p<0.001), ejection fraction (EF) (51±4% to 44±6%; p<0.001), stroke work (SW) (4483±1023 ml*mmHg to 2383±719 ml*mmHg; p<0.001), and LV peak positive dP/dt (825 ± 184 mmHg/s to 523 ± 99 mmHg/s; p<0.001). Conversely, the native RV experienced preload-mediated increase in SV (65±7 ml to 86±20 ml; p<0.001), CO (3.7±0.8 ml/min to 4.3±0.9 ml/min; p<0.001), EF (53±4% to 58±11%; p<0.001), SW (918±143 ml*mmHg to 1529±365 ml*mmHg; p<0.001), and RV dP/dt (164±16 mmHg/s to 228±29 mmHg/s, p<0.001). Load independent contractility was assessed in the LV (1.64±0.33 mmHg/ml to 1.71±0.41 mmHg/ml; p=0.2) and RV (0.25±0.04 mmHg/ml to 0.29±0.05 mmHg/ml; p<0.001). Conclusions: This study highlights ventricular interdependence with Impella 5.5 support with opposing BiV trends. In a healthy heart, the RV can adequately compensate for increased preload offered by the device.

Percutaneous ventricular assist devices (pVAD) decrease mortality in cardiogenic shock (CS) patients, but at a high adverse event rate. Novel pVADs need to improve cardiac power output (CPO) to improve efficacy and reduce profile to reduce adverse events. Venstramedical has developed an impeller with nitinol and polymer which can collapse for low-profile insertion and expand in the body to provide optimal CPO. We have also developed a unique 9 French (9Fr) delivery system. In vitro and in vivo testing have been performed to develop this device. Head-flow (HQ) tests generate 5.0 L/min with a pressure differential of 80 mm Hg and 7.0 L/min against 60 mm Hg. Durability testing demonstrated continuous operation of up to 20 days. In the acute healthy ovine model, we demonstrated full flow (7–9 L against 60–80 mm Hg), transcatheter 9Fr delivery, retrieval of the device, and resting of the native heart during pumping. In a CS animal, we demonstrated survival and resting of the native heart during the acute study with decreased stroke work (SW), decreased stroke volume (SV), while total cardiac output was up to 7 L/min and maintaining adequate pressure with low hemolysis. We also demonstrated multiday functioning of the device in a healthy ovine model with good CO and low hemolysis.

Purpose of review The increasing prevalence of hypertension, alongside the growing use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) for conditions beyond type 2 diabetes, underscores the need for understanding if there is a role for these medications in blood pressure management. This review addresses the timely opportunity to assess how GLP-1 RAs could influence blood pressure control, potentially broadening therapeutic strategies for cardiovascular risk management. Recent findings Emerging literature indicates that GLP-1 RAs influence blood pressure through various mechanisms, such as sympathetic nervous modulation, vasodilation, and diuretic effects. Clinical trials demonstrate modest yet statistically significant reductions in systolic blood pressure (SBP), with less consistent effects on diastolic blood pressure (DBP). The advent of dual GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptor agonists presents enhanced possibilities for managing hypertension. Summary The implications of these findings suggest that GLP-1 RAs have potential as adjunctive therapies for hypertension, especially in patients already receiving these agents for other cardiometabolic conditions. The blood pressure-lowering effects, often independent of weight loss or glucose control, warrant further investigation to determine their precise role within hypertension treatment algorithms and encourage integration into clinical practice.

ABSTRACT Background Addition of left heart catheterization (LHC) to exercise protocols allows for a unique focus on parameters of systolic and diastolic responses to increased activity in patients with left ventricular assist device (LVAD) support. Methods A retrospective review was conducted of all consecutive adult patients who underwent LHC with exercise for any indication from June 2017 to June 2023. For all patients, the relationship between exercise and parameters of LV systolic and diastolic response was assessed. Patients were divided into two cohorts based on the indication for testing: hemodynamic optimization (Optim, n = 5) or weaning consideration (Wean, n = 3). Results Eight patients (88% male, median age 57 years (IQR 44, 65)) were included. LVEF was 45% (IQR 45, 56) in Wean and 25% (IQR 20, 42) in Optim. LV systolic work index (LVSWI) increased more rapidly over levels of exercise in Wean vs. Optim (slope 46.3 vs. −0.625; p = 0.044) and LVSWI rose more quickly at lower levels of LV end diastolic pressure (LVEDP) in Wean vs. Optim (slope 219.5 vs. −2.008; p = 0.0026). Pulse power index was higher in Wean patients at baseline (0.046 (IQR 0.04, 0.07) vs. 0.016 (IQR 0.001, 0.04); p = 0.14) and peak exercise (0.12 (IQR 0.12, 0.12) vs. 0.06 (IQR 0.03, 0.1); p = 0.29). Conclusions Patients with favorable remodeling on LVAD support have significantly improved LV systolic and diastolic responses to exercise and a trend of higher systemic pulsatility. Improving our understanding of LV‐LVAD interactions with activity may aid in future efforts to improve exercise tolerance through speed modulation.

Axillary artery intra-aortic balloon pump (axIABP) placement has been implemented as a bridging solution before heart transplantation. This study evaluates complications associated with axIABP support and describes an approach to minimize adverse events. We previously described a percutaneous approach for axIABP placement. However, patients receiving axIABP between September 1, 2017, and September 26, 2019 (n = 32) demonstrated a high rate of balloon pump malfunction (8/32; 25%) and other complications (totaling 15/32; 47%). Sixty-four patients were sequentially treated under a revised protocol. Compared to the initial cohort, no significant differences in demographics were noted. A significant reduction in rate of balloon malfunction (8/32, 25% vs. 1/64, 2%; p < 0.001) and total complications (15/32, 47% vs. 10/64, 16%; p = 0.0025) during the period of support were noted after intervention. Subsequent analysis of total complications per device size (40 vs. ≤ 34 ml balloon) revealed significantly reduced complications in patients with smaller devices (40% vs. 13%, respectively; p = 0.0022). This study provides guidelines to limit complications in patients supported with axIABP, facilitating a protracted period of bridging support.

Background The purpose of this study was to investigate a therapeutic approach targeting the inflammatory response and consequent remodeling from ischemic myocardial injury. Methods and Results Coronary thrombus aspirates were collected from patients at the time of ST‐segment–elevation myocardial infarction and subjected to array‐based proteome analysis. Clinically indistinguishable at myocardial infarction (MI), patients were stratified into vulnerable and resilient on the basis of 1‐year left ventricular ejection fraction and death. Network analysis from coronary aspirates revealed prioritization of tumor necrosis factor‐α signaling in patients with worse clinical outcomes. Infliximab, a tumor necrosis factor‐α inhibitor, was infused intravenously at reperfusion in a porcine MI model to assess whether infliximab‐mediated immune modulation impacts post‐MI injury. At 3 days after MI (n=7), infliximab infusion increased proregenerative M2 macrophages in the myocardial border zone as quantified by immunofluorescence (24.1%±23.3% in infliximab versus 9.29%±8.7% in sham; P <0.01). Concomitantly, immunoassays of coronary sinus samples quantified lower troponin I levels (41.72±7.34 pg/mL versus 58.11±10.75 pg/mL; P <0.05) and secreted protein analysis revealed upregulation of injury‐modifying interleukin‐2, ‐4, ‐10, ‐12, and ‐18 cytokines in the infliximab‐treated cohort. At 4 weeks (n=12), infliximab treatment resulted in significant protective influence, improving left ventricular ejection fraction (53.9%±5.4% versus 36.2%±5.3%; P <0.001) and reducing scar size (8.31%±10.9% versus 17.41%±12.5%; P <0.05). Conclusions Profiling of coronary thrombus aspirates in patients with ST‐segment–elevation MI revealed highest association for tumor necrosis factor‐α in injury risk. Infliximab‐mediated immune modulation offers an actionable pathway to alter MI‐induced inflammatory response, preserving contractility and limiting adverse structural remodeling.

AbstractRamp studies are utilized for speed optimization of continuous flow left ventricular assist devices (CF‐LVADs). We here report the utility of combined left and right heart catheterization during a ramp study to ensure a comprehensive understanding of the hemodynamic implications on both ventricles. Pressure‐volume loop (PV loop) monitoring uncovered compromised systolic and mildly compromised right ventricular function with increasing LVAD speeds, despite improvement in left ventricular unloading. These findings informed patient management and highlight the potential utility of PV loop monitoring as an adjunct to left and right heart catheterization during ramp studies of next‐generation LVADs.

The purpose of this study was to evaluate left ventricular (LV) unloading strategies in patients supported with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). A retrospective review was conducted of all consecutive patients requiring VA-ECMO support for any indication, who underwent novel LV unloading strategies with either direct left atrial venoarterial (LAVA) cannulation or pulmonary artery venoarterial (PAVA) venting, in comparison to Impella and intra-aortic balloon pump (IABP). The primary outcome was successful bridge to transplant, LV assist device, or myocardial recovery. Forty-six patients (63% male, mean age 52.8 ± 17.6 years) were included. Fourteen patients (30%) underwent novel unloading with either LAVA or PAVA, 11 patients (24%) underwent IABP placement, and 21 patients (46%) underwent Impella insertion. In the novel LV unloading cohort, 10 patients (71%) survived to hospital discharge. Four patients (29%) were weaned from ECMO and eight patients (57%) underwent cardiac transplantation. Although a trend favoring cannula-based unloading for the primary outcome was noted, the cohort was too small for statistical significance (79% LAVA/PAVA, 57% Impella, 45% IABP; p = 0.21). However, probability of survival was greater in the LAVA/PAVA cohort compared to Impella and IABP (p < 0.05). Thus, we demonstrate the efficacy of LA and PA cannulation as an alternative LV unloading strategy for patients supported with peripheral VA-ECMO.