Dasatinib induces endothelial dysfunction leading to impaired recovery from ischaemia.

Chronic myeloid leukaemia (CML) management is complicated by treatment-emergent vascular adverse events seen with tyrosine kinase inhibitors (TKIs) such as nilotinib, dasatinib and ponatinib. Pleural effusion and pulmonary arterial hypertension (PAH) have been associated with dasatinib treatment. Endothelial dysfunction and impaired angiogenesis are hallmarks of PAH. In this study, we explored, at cellular and whole animal levels, the connection between dasatinib exposure and disruption of endothelial barrier integrity and function, leading to impaired angiogenesis. Understanding the mechanisms whereby dasatinib initiates PAH will provide opportunities for intervention and prevention of such adverse effects, and for future development of safer TKIs, thereby improving CML management.

Mitral valve gradient changes associate with outcomes of patients undergoing transcatheter edge-to-edge repair.

INTRODUCTION: Transcatheter edge-to-edge repair (TEER) is typically used to treat mitral regurgitation (MR) in patients with high surgical risk. Increased post-procedural mitral valve gradient (MVG) may impact mortality and hospitalizations. We aim to evaluate and compare the absolute postprocedural MVG and the change in the MVG effect on outcomes for patients undergoing TEER therapy. METHODS: Patients who underwent TEER for severe MR were divided into two groups, initially by postprocedural absolute MVG, TTE-based at discharge, and then by the difference between preprocedural and postprocedural MVG. Primary endpoints included all-cause mortality and heart failure hospitalization (HFH) during one year after the procedure. RESULTS: The study included 100 patients. The mean MVG increased from 3.39 mmHg immediately after the procedure to 4.83 mmHg the following day, an increase of 1.44 mmHg (p < 0.001). First stratification was by MVG on the day following the procedure - MVG ≤5 mmHg (n = 70) and MVG >5 mmHg (n = 30). There was no significant difference in rates of survival (88.6%, 93.3%, p = 0.716) or HFH (18.6%, 33.3%, p = 0.178). Second stratification was by the difference in preprocedural and postprocedural MVG- delta MVG <3 mmHg (n = 55) and delta MVG ≥3 mmHg (n = 45). While survival rates did not significantly differ (87.3% vs. 93.3%, p = 0.503), delta MVG ≥3 mmHg correlated with higher HFH rates (12.7% vs. 35.6%, p = 0.014). CONCLUSIONS: The MVG of patients undergoing TEER usually increases on the day after the procedure compared to the immediate post-procedure MVG. Higher delta MVG is associated with higher HFH rate.

Performance of a novel artificial intelligence software developed to derive coronary fractional flow reserve values from diagnostic angiograms.

BACKGROUND: Although invasive measurement of fractional flow reserve (FFR) is recommended to guide revascularization, its routine use is underutilized. Recently, a novel non-invasive software that can instantaneously produce FFR values from the diagnostic angiograms, derived completely from artificial intelligence (AI) algorithms has been developed. We aim to assess the accuracy and diagnostic performance of AI-FFR in a real-world retrospective study. METHODS: Retrospective, three-center study comparing AI-FFR values with invasive pressure wire-derived FFR obtained in patients undergoing routine diagnostic angiography. The accuracy, sensitivity, and specificity of AI-FFR were analyzed. RESULTS: A total of 304 vessels from 297 patients were included. Mean invasive FFR was 0.86 vs. 0.85 AI-FFR (mean difference: -0.005, P  = 0.159). The diagnostic performance of AI-FFR demonstrated sensitivity of 91%, specificity 95%, positive predictive value 83% and negative predictive value 97%. Overall accuracy was 94% and the area under curve was 0.93 (95% CI 0.88-0.97). 105 lesions fell around the cutoff value (FFR = 0.75-0.85); in this sub-group, AI-FFR demonstrated sensitivity of 95%, and specificity 94%, with an AUC of 0.94 (95% CI 88.2-98.0). AI-FFR calculation time was 37.5 ±â€…7.4 s for each angiographic video. In 89% of cases, the software located the target lesion and in 11%, the operator manually marked the target lesion. CONCLUSION: AI-FFR calculated by an AI-based, angio-derived method, demonstrated excellent diagnostic performance against invasive FFR. AI-FFR calculation was fast with high reproducibility.

Urgent transcatheter edge-to-edge repair for severe mitral regurgitation with flail leaflet in critically Ill patients.

Introduction: Degenerative mitral valve disease (DMR) is a common valvular disorder, with flail leaflets due to ruptured chordae representing an extreme variation of this pathology. Ruptured chordae can present as acute heart failure which requires urgent intervention. While mitral valve surgery is the preferred mode of intervention, many patients have significantly elevated surgical risk and are sometimes considered inoperable. We aim to characterize patients with ruptured chordae undergoing urgent transcatheter edge-to-edge repair (TEER), and to analyze their clinical and echocardiographic outcomes. Methods: We screened all patients who underwent TEER at a tertiary referral center in Israel. We included patients with DMR with flail leaflet due to ruptured chordae and categorized them into elective and critically ill groups. We evaluated the echocardiographic, hemodynamic, and clinical outcomes of these patients. Results: The cohort included 49 patients with DMR due to ruptured chordae and flail leaflet, who underwent TEER. Seventeen patients (35%) underwent urgent intervention and 32 patients (65%) underwent an elective procedure. In the urgent group, the average age of the patient was 80.3, with 41.8% being female. Fourteen patients (82%) received noninvasive ventilation, and three patients (18%) required invasive mechanical ventilation. One patient died due to tamponade, while echo evaluation of the other 16 patients demonstrated successful reduction of ≥2 in the MR grade. Left atrial V wave decreased from 41.6 mmHg to 17.9 mmHg (p < 0.001), and the pulmonic vein flow pattern changed from reversal (68.8%) to a systolic dominant flow in all patients (p = 0.001). After the procedure, 78.5% of patients improved to New York Heart Association (NYHA) class I or II (p < 0.001). There was no significant difference in the overall mortality between the urgent and elective groups, with similar 6 months survival rates for each group. Conclusion: Urgent TEER in patients with ruptured chordae and flail leaflets can be safe and feasible with favorable hemodynamic, echocardiographic, and clinical outcomes.

A novel robotic radiation shielding device for electrophysiologic procedures: A prospective study.

BACKGROUND: A robotic Radiaction Shielding System (RSS) was developed to provide a full-body protection to all medical personnel during fluoroscopy-guided procedures, by encapsulating the imaging beam and blocking scattered radiation. OBJECTIVES: We aimed to evaluate its efficacy in real-world electrophysiologic (EP) laboratory- both during ablations and cardiovascular implantable electronic devices (CIED) procedures. METHODS: A prospective controlled study comparing consecutive real-life EP procedures with and without RSS using highly sensitive sensors in different locations. RESULTS: Thirty-five ablations and 19 CIED procedures were done without RSS installed and 31 ablations and 24 CIED procedures (17 with usage levels ≥70%) were done with RSS. Overall, there was 95% average usage level for ablations and 88% for CIEDs. For all procedures with ≥70% usage level and for all sensors, the radiation with RSS was significantly lower than radiation without RSS. For ablations, there was 87% reduction in radiation with RSS (76%-97% for different sensors). For CIEDs, there was 83% reduction in radiation with RSS (59%-92%). RSS usage did not increase procedure time and radiation time. User feedback showed a high-level of integration in the clinical workflow and safety profile for all types of EP procedures. CONCLUSIONS: For both CIED and ablation procedures the radiation with RSS was significantly lower than without RSS. Higher usage level brings higher reduction rates. Thus, RSS may have an important role in full-body protection to all medical personnel from scattered radiation during EP and CIED procedures. Until more data is available, it is recommended to maintain existing standard shielding.

First-in-Human Dedicated Leaflet Splitting Device for Prevention of Coronary Obstruction in Transcatheter Aortic Valve Replacement.

BACKGROUND: Coronary artery obstruction is a life-threatening complication of transcatheter aortic valve replacement (TAVR) procedures. Current preventive strategies are suboptimal. OBJECTIVES: The aim of this study was to describe bench testing and clinical experience with a novel device that splits valve leaflets that are at risk for causing coronary obstruction after TAVR, allowing normal coronary flow. METHODS: The ShortCut device was initially tested in vitro and preclinically in a porcine model for functionality and safety. The device was subsequently offered to patients at elevated risk for coronary obstruction. Risk for coronary obstruction was based on computed tomography-based anatomical characteristics. Procedure success was determined as patient survival at 30 days with a functioning new valve, without stroke or coronary obstruction. RESULTS: Following a successful completion of bench testing and preclinical trial, the device was used in 8 patients with failed bioprosthetic valves (median age 81 years; IQR: 72-85 years; 37.5% man) at 2 medical centers. A total of 11 leaflets were split: 5 patients (63.5%) were considered at risk for left main obstruction alone, and 3 patients (37.5%) were at risk for double coronary obstruction. All patients underwent successful TAVR without evidence of coronary obstruction. All patients were discharged from the hospital in good clinical condition, and no adverse neurologic events were noted. Procedure success was 100%. CONCLUSIONS: Evaluation of the first dedicated transcatheter leaflet-splitting device shows that the device can successfully split degenerated bioprosthetic valve leaflets. The procedure was safe and successfully prevented coronary obstruction in patients at risk for this complication following TAVR.

Urgent Transcatheter Edge-to-Edge Repair for Severe Mitral Regurgitation in Patients with Refractory Cardiogenic Shock.

Introduction Patients suffering from cardiogenic shock (CS) and mitral regurgitation (MR) demonstrate worse prognosis, with higher mortality rates. We sought to evaluate the effectiveness of urgent valve intervention of the mitral valve, using transcatheter edge-to-edge repair (TEER) procedures in patients presenting with CS in a tertiary Intensive Coronary Care Unit (ICCU). Methods and Results Patients with unremitting CS and severe MR were selected for urgent TEER. Baseline clinical and echocardiographic characteristics were recorded, as well as procedural success (MR severity and hemodynamics), and 30-days and 6-month mortality. Urgent TEER was done in 13 patients, whose average age was 70 years; 12 (92%) of the patients were male. All 13 patients had suffered previous ischemic heart disease-12 (92%) with either acute severe MR or worsening of previously known MR by an acute ischemic event. Using the SCAI criteria, 8 patients (61%) were classified as 'E' (Extreme) category; 4 (31%) were classified as 'C'. At 30 days, 12 out of the 13 patients survived (corresponding to an 8% mortality rate); all of those 12 patients remained alive at 6 months post-admission/procedure. Conclusions The use of TEER was associated with greater 30-day and 6-month survival rates, compared to the worldwide mortality rates of patients admitted with CS. This finding may change the previous paradigm that CS and MR are associated with the worst outcome, and we might be able to offer these patients a safe and effective therapeutic option.

Simultaneous Noninvasive Detection and Therapy of Atherosclerosis Using HDL Coated Gold Nanorods.

Cardiovascular disease (CVD) is a major cause of death and disability worldwide. A real need exists in the development of new, improved therapeutic methods for treating CVD, while major advances in nanotechnology have opened new avenues in this field. In this paper, we report the use of gold nanoparticles (GNPs) coated with high-density lipoprotein (HDL) (GNP-HDL) for the simultaneous detection and therapy of unstable plaques. Based on the well-known HDL cardiovascular protection, by promoting the reverse cholesterol transport (RCT), injured rat carotids, as a model for unstable plaques, were injected with the GNP-HDL. Noninvasive detection of the plaques 24 h post the GNP injection was enabled using the diffusion reflection (DR) method, indicating that the GNP-HDL particles had accumulated in the injured site. Pathology and noninvasive CT measurements proved the recovery of the injured artery treated with the GNP-HDL. The DR of the GNP-HDL presented a simple and highly sensitive method at a low cost, resulting in simultaneous specific unstable plaque diagnosis and recovery.

Immature platelets in patients with Covid-19: association with disease severity.

Coronavirus disease 2019 (Covid-19) is associated with a high incidence of venous and arterial thromboembolic events. Currently, there are no clinical or laboratory markers that predict thrombotic risk. Circulating immature platelets are hyper-reactive platelets, which are associated with arterial thrombotic events. The aim of this study was to assess whether the proportion of circulating immature platelets is associated with disease severity in Covid-19 patients. Patients admitted with Covid-19 disease were prospectively assessed. Immature platelet count (IPC) and immature platelet fraction (IPF) were measured at admission and at additional time points during the hospital course using the Sysmex XN-3000 auto-analyzer. A total of 136 consecutive patients with Covid-19 were recruited [mean age 60 ± 19 years, 49% woman, 56 (41%) had mild-moderate disease and 80 (59%) had severe disease at presentation]. The median IPF% was higher in patients with severe compared to mild-moderate disease [5.8 (3.9-8.7) vs. 4.2 (2.73-6.45), respectively, p = 0.01]. The maximal IPC value was also higher in patients with severe disease [15 (10.03-21.56), vs 10.9 (IQR 6.79-15.62), respectively, p = 0.001]. Increased IPC was associated with increased length of hospital stay. Patients with severe Covid-19 have higher levels of IPF than patients with mild-moderate disease. IPF may serve as a prognostic marker for disease severity in Covid-19 patients.

Immature platelets in patients hospitalized with Covid-19.

Coronavirus disease 2019 (Covid-19) is associated with high incidence of venous and arterial thromboembolic events. Currently, there are no markers to guide antithrombotic therapy in Covid-19. Immature platelets represent a population of hyper-reactive platelets associated with arterial events. This prospective study compared consecutive Covid-19 patients (n = 47, median age = 56 years) to patients with acute myocardial infarction (AMI, n = 100, median age = 59 years) and a group of stable patients with cardiovascular risk factors (n = 64, median age = 68 years). Immature platelet fraction (IPF) and immature platelet count (IPC) were determined by the Sysmex XN-3000 auto-analyzer on admission and at subsequent time-points. IPF% on admission was higher in Covid-19 than the stable group and similar to the AMI group (4.8% [IQR 3.4-6.9], 3.5% [2.7-5.1], 4.55% [3.0-6.75], respectively, p = 0.0053). IPC on admission was also higher in Covid-19 than the stable group and similar to the AMI group (10.8 × 109/L [8.3-18.1], 7.35 × 109/L [5.3-10.5], 10.7 × 109/L [7.7-16.8], respectively, P < 0.0001). The maximal IPF% among the Covid-19 group was higher than the stable group and similar to the AMI group. The maximal IPC in Covid-19 was higher than the maximal IPC in both the stable and AMI groups (COVID-19: 14.4 × 109/L [9.4-20.9], AMI: 10.9 × 109/L [7.6-15.2], P = 0.0035, Stable: 7.55 × 109/L [5.55-10.5], P < 0.0001). Patients with Covid-19 have increased immature platelets indices compared to stable patients with cardiovascular risk factors, and as the disease progresses also compared to AMI patients. The enhanced platelet turnover and reactivity may have a role in the development of thrombotic events in Covid-19 patients.

Advances in mammalian target of rapamycin kinase inhibitors: application to devices used in the treatment of coronary artery disease.

Mammalian target of rapamycin (mTOR) inhibitors have been applied to vascular coronary devices to avoid neointimal growth and have become the predominant pharmacological agents used to prevent restenosis. mTOR inhibitors can affect not only proliferating vascular smooth muscle cells but also endothelial cells and therefore can result in delayed healing of the vessel including endothelialization. Emerging evidence suggests accelerated atherosclerosis due to the downstream negative effects on endothelial barrier functional recovery. The development of neoatherosclerosis within the neointima of drug-eluting stents can result in late thrombotic events. This type of problematic healing response may open the way for specific mTOR kinase inhibitors, such as ATP-competitive mTOR inhibitors. These inhibitors demonstrate a better healing profile than traditional limus-based drug-eluting stent and their clinical efficacy remains unknown.

Drug-eluting coronary stents: insights from preclinical and pathology studies.

Implantation of drug-eluting stents (DES) is the dominant treatment strategy for patients with symptomatic coronary artery disease. However, the first-generation DES had substantial drawbacks, including delayed healing, local hypersensitivity reactions and neoatherosclerosis, which all led to a steady increase in major adverse cardiovascular events over time. Subsequently, newer-generation DES were introduced with thinner struts, different scaffold designs (to improve deliverability while maintaining radial strength), different durable and biodegradable polymers - and in some cases no polymer (to improve vascular biocompatibility) - and new antiproliferative drug types and doses. Currently, >30 different DES are commercially available in Europe, with fewer available in the USA but with many new entrants coming onto the US market in the next few years. Never before have cardiologists been faced with so many choices of stent, each with its own unique design. In this Review, we detail preclinical and pathology studies for each stent design, examining thromboresistance, speed of neointimal coverage and completeness of healing, including endothelialization. We conclude by discussing how these design characteristics might affect the potential for shortening the minimum duration of dual antiplatelet therapy needed after coronary intervention.

Pathology of stent implantation in internal mammary artery.

The internal mammary artery (IMA) is the most durable conduit for bypassing the left anterior descending (LAD) coronary artery in patients undergoing coronary artery bypass graft surgery (CABG). However, little is known about how the IMA reacts histologically to stent implantation. From CVPath stent registry (1048 lesions, 614 cases), we obtained 4 stent lesions (2 bare metal stents, 2 drug-eluting stents) involving IMA grafts. The mean age of our patients was 63 years and the duration of stent implantation in the IMA ranged from 5 days to 5 years. Stented arteries were dissected from hearts and embedded in plastic, segmented at 3 mm intervals, sectioned at 4-6 microns and stained with H&E and Movat pentachrome stains. Histological observations were performed. Majority of stents (3 of 4) were implanted in anastomosis between IMA and LAD while 1 stent was implanted in IMA body. One stent with duration of 5 days showed stent thrombosis while others were all patent with fully coverage by varying degrees of neointima. Foamy macrophage, lipid pool and calcification in neointima were observed in 1 stent with duration of 5 years but it was limited only to the distal LAD part within the stented segment. Overall, in this small pathologic series, the majorities of stents were implanted in IMA-to-LAD anastomosis site and demonstrated acceptable pathologic responses.

Direct Targeting of the mTOR (Mammalian Target of Rapamycin) Kinase Improves Endothelial Permeability in Drug-Eluting Stents-Brief Report.

Objective- Drug-eluting stents eluting canonical mTOR (mammalian target of rapamycin) inhibitors are widely used to treat coronary artery disease but accelerate the development of atherosclerosis within the stent (neoatherosclerosis)-a leading cause of late stent failure. We recently showed that canonical mTOR inhibitors bind FKBP12.6 (12.6-kDa FK506-binding protein 12), displace it from calcium release channels, resulting in activation of PKCα (protein kinase Cα) and dissociation of p-120-catenin (p120) from VE-CAD (vascular endothelial cadherin; promoting endothelial barrier dysfunction [EBD]). However, the relevance of these findings to drug-eluting stents remains unknown. Newer generation direct mTOR kinase inhibitors do not bind FKBP12.6 and offer the potential of improving endothelial barrier function while maintaining antirestenotic efficacy, but their actual effects are unknown. We examined the effects of 2 different pharmacological targeting strategies-canonical mTOR inhibitor everolimus and mTOR kinase inhibitors Torin-2-on EBD after stenting. Approach and Results- Using the rabbit model of stenting and a combination of Evans blue dye, confocal and scanning electron microscopy studies, everolimus-eluting stents resulted in long-term EBD compared with bare metal stents. EBD was mitigated by using stents that eluted mTOR kinase inhibitors (Torin-2-eluting stent). At 60 days after stent placement, everolimus-eluting stents demonstrated large areas of Evans blue dye staining and evidence of p120 VE-CAD dissociation consistent with EBD. These findings were absent in bare metal stents and significantly attenuated in Torin-2-eluting stent. As proof of concept of the role of EBD in neoatherosclerosis, 100 days after stenting, animals were fed an enriched cholesterol diet for an additional 30 days. Everolimus-eluting stents demonstrated significantly more macrophage infiltration (consistent with neoatherosclerosis) compared with both bare metal stents and Torin-2-eluting stent. Conclusions- Our results pinpoint interactions between FKBP12.6 and canonical mTOR inhibitors as a major cause of vascular permeability and neoatherosclerosis, which can be overcome by using mTOR kinase inhibitors. Our study suggests further refinement of molecular targeting of the mTOR complex may be a promising strategy (Graphic Abstract).

Biologic Drug Effect and Particulate Embolization of Drug-Eluting Stents versus Drug-Coated Balloons in Healthy Swine Femoropopliteal Arteries.

PURPOSE: To compare the drug effect in treated vessels and downstream effects in distal skeletal muscle of drug-coated balloons (DCBs) and drug-eluting stents (DESs) in a healthy preclinical swine model. MATERIALS AND METHODS: Four groups of treated iliofemoral arteries (percutaneous transluminal angioplasty [PTA]+DES, DCB+DES, DCB+bare metal stent [BMS], and DCB alone) of 12 healthy swine were assessed, with euthanasia at 30 days. Biological drug effect was evaluated using smooth muscle cell (SMC) loss score according to both depth and circumference as well as a neointimal fibrin and medial proteoglycan scores which were compared between the 4 groups. Vascular and skeletal muscle changes in regions downstream from the treated site were also assessed histologically for evidence of emboli. RESULTS: DESs showed greater medial SMC loss in the treated arteries irrespective of preceding DCB or PTA treatment in terms of depth (DCB+DES vs PTA+DES vs DCB+BMS vs DCB alone; median, 4.0 mm vs 3.8 mm vs 3.0 mm vs 2.2 mm; P = .009) and circumference (4.0 mm vs 3.5 mm vs 2.0 mm vs 1.2 mm, respectively; P = .007). Sections of skeletal muscles downstream from the treated arteries showed arteriolar changes of fibrinoid necrosis consistent with paclitaxel effect exclusively in the DCB groups (DCB+BMS, 26.9% of sections; DCB+DES, 14.3%; DCB alone, 19.2%; PTA+DES, 0%; P = .02). CONCLUSIONS: In the treated arteries, irrespective of preceding DCB treatment or PTA, DES treatment showed maximum drug effects vs DCB alone or in combination with BMS placement, and there was no detrimental toxic effect in DCB-treated iliofemoral arteries before DES treatment compared with PTA before DES treatment. Downstream vascular changes were exclusively seen in groups treated with DCBs.