MR Uniformity Ratio Estimates to Evaluate Ventricular Mechanical Dyssynchrony and Prognosis After ST-Segment Elevation Myocardial Infarction.

BACKGROUND: The impact of left ventricular mechanical dyssynchrony (LVMD) on the long-term prognosis of ST-segment elevation myocardial infarction (STEMI) is unclear. HYPOTHESIS: MR uniformity ratio estimates (URE) can detect LVMD and assess STEMI prognosis. STUDY TYPE: Retrospective analysis of a prospective multicenter registry (EARLY-MYO trial, NCT03768453). POPULATION: Overall, 450 patients (50 females) with first-time STEMI were analyzed, as well as 40 participants without cardiovascular disease as controls. FIELD STRENGTH/SEQUENCE: 3.0-T, balanced steady-state free precession cine and late gadolinium enhancement imaging. ASSESSMENT: MRI data were acquired within 1 week of symptom onset. Major adverse cardiovascular events (MACEs), including cardiovascular death, nonfatal re-infarction, hospitalization for heart failure, and stroke, were the primary clinical outcomes. LVMD was represented by circumferential URE (CURE) and radial URE (RURE) calculated using strain measurements. The patients were grouped according to clinical outcomes or URE values. Patients' clinical characteristics and MR indicators were compared. STATISTICAL TESTS: The Student's t-test, Mann-Whitney U test, chi-square test, Fisher's exact test, receiver operating characteristic curve analysis with area under the curve, Kaplan-Meier analysis, Cox regression, logistic regression, intraclass correlation coefficient, c-index, and integrated discrimination improvement were used. P < 0.05 was considered statistically significant. RESULTS: CURE and RURE were significantly lower in patients with STEMI than in controls. The median follow-up was 60.5 months. Patients with both lower CURE and RURE values experienced a significantly higher incidence of MACEs by 3.525-fold. Both CURE and RURE were independent risk factors for MACEs. The addition of UREs improved diagnostic efficacy and risk stratification based on infarct size and left ventricular ejection fraction (LVEF). The indicators associated with LVMD included male sex, serum biomarkers (peak creatine phosphokinase and cardiac troponin I), infarct size, and LVEF. DATA CONCLUSION: CURE and RURE may be useful to evaluate long-term prognosis after STEMI. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

CdSe/TiO2NTs Heterojunction-Based Nonenzymatic Photoelectrochemical Sensor for Glucose Detection.

Compared with a single semiconductor, the heterojunction formed by two different semiconductors usually has higher light utilization and better photoelectric performance. By using stable TiO2 nanotubes as the main subject, CdSe/TiO2NTs heterojunctions were synthesized by a hydrothermal method. XRD, TEM, SEM, PL, UV-vis, and EIS were used to characterize the fabricated CdSe/TiO2NTs. Under visible light irradiation, CdSe/TiO2NTs heterojunctions exhibited a higher absorption intensity and lower degree of photogenerated carrier recombination than TiO2. The electrons and holes were proven to be effectively separated in this heterojunction via theoretical calculation. Under CdSe/TiO2NTs' optimal conditions, the glucose concentrations (10-90 µM) had a linear relationship with the photocurrent value, and the detection limit was 3.1 µM. Moreover, the CdSe/TiO2NTs sensor exhibited good selectivity and stability. Based on the experimental data and theoretical calculations, its PEC sensing mechanism was also illuminated.

Peak early diastolic strain rate improves prediction of adverse cardiovascular outcomes in patients with ST-elevation myocardial infarction.

BACKGROUND: The prognostic role of diastolic dysfunction measured by the circumferential peak early diastolic strain rate (PEDSR) on ST-elevation myocardial infarction (STEMI) is not completely established. OBJECTIVES: We aimed to investigate the prognostic value of diastolic function by measuring PEDSR within 1 week after STEMI. METHODS: The cardiac magnetic resonance (CMR) pictures of 420 subjects from a clinical registry study (NCT03768453) were analyzed and the composite major adverse cardiac events (MACEs) were followed up. RESULTS: The PEDSR of patients was significantly lower compared with that of control subjects (P < 0.001). Within the median follow-up period of 52 months, PEDSR of patients who experienced MACEs deceased more significantly than that of patients without MACEs (P < 0.001). After adjusting with clinical or CMR indexes, per 0.1/s reduction of PEDSR increased the risks of MACEs to 1.402 or 1.376 fold and the risk of left ventricular (LV) remodeling to 1.503 or 1.369 fold. When PEDSR divided by best cutoff point, significantly higher risk of MACEs (P < 0.001) and more remarkable LV remodeling (P < 0.001) occurred in patients with PEDSR ≤ 0.485/s. Moreover, when adding the PEDSR to the conventional prognostic factors such as LV ejection fraction and infarction size, better prognostic risk classification models were created. Finally, aging, tobacco use, remarkable LV remodeling, and a low LV ejection fraction were factors related with the reduction of PEDSR. CONCLUSIONS: Diastolic dysfunction has an important prognostic effect on patients with STEMI. Measurement of the PEDSR in the acute phase could serve as an effective index to predict the long-term risk of MACEs and cardiac remodeling.

Nomograms referenced by cardiac magnetic resonance in the prediction of cardiac injuries in patients with ST-elevation myocardial infarction.

BACKGROUND: Evaluation of cardiac injuries is essential in patients with ST-elevation myocardial infarction (STEMI). Cardiac magnetic resonance (CMR) has become the gold standard for quantifying cardiac injuries; however, its routine application is limited. A nomogram is a useful tool for prognostic prediction based on the comprehensive utilization of clinical data. We presumed that the nomogram models established using CMR as a reference could precisely predict cardiac injuries. METHODS: This analysis included 584 patients with acute STEMI from a CMR registry study for STEMI (NCT03768453). The patients were divided into training (n = 408) and testing (n = 176) datasets. The least absolute shrinkage and selection operator method and multivariate logistic regression were used to construct nomograms for predicting left ventricular ejection fraction (LVEF) ≤40%, infarction size (IS) ≥ 20% on the LV mass, and microvascular dysfunction. RESULTS: The nomogram for predicting LVEF≤40%, IS≥20%, and microvascular dysfunction comprised 14, 10, and 15 predictors, respectively. With the nomograms, the individual risk probability of developing specific outcomes could be calculated, and the weight of each risk factor was demonstrated. The C-index of the nomograms in the training dataset were 0.901, 0.831, and 0.814, respectively, and were comparable in the testing set, showing good nomogram discrimination and calibration. The decision curve analysis demonstrated good clinical effectiveness. Online calculators were also constructed. CONCLUSIONS: With the CMR results as the reference standard, the established nomograms demonstrated good effectiveness in predicting cardiac injuries after STEMI and could provide physicians with a new option for individual risk stratification.

Rationale and design of a prospective multi-center randomized trial of EARLY treatment by rivaroxaban versus warfarin in ST-segment elevation MYOcardial infarction with Left Ventricular Thrombus (EARLY-MYO-LVT trial).

BACKGROUND: Left ventricular thrombus (LVT), a common complication of acute ST-segment elevation myocardial infarction (STEMI), is associated with increased risk of systemic embolism and high mortality. Current STEMI guidelines recommend adding anticoagulant therapy to dual antiplatelet therapy (DAPT) if early-formulated LVT were detected, for which vitamin K antagonist (VKA) is the standard anticoagulant agent. The role of non-VKA oral anticoagulants (NOACs) in this scenario is uncertain. METHODS: The EARLY-MYO-LVT study will be a prospective, multi-center and randomized trial designed to investigate the efficacy and safety of rivaroxaban versus warfarin in the treatment of post-STEMI LVT. It will enroll 280 patients with STEMI who have developed LVT within the first month of symptom onset. They will be randomized at 1:1 ratio into the group of rivaroxaban 15 mg daily or VKA treatment (with targeted INR 2-2.5) on the basis of standard DAPT (100 mg daily aspirin plus 75 mg daily clopidogrel) for 3-6 months. The primary efficacy endpoint will be the probability of LVT resolution after 3-month triple therapy, and the principal safety outcome will be the incidence of major bleeding events during the treatment. DISCUSSION: The described study will systemically assess the efficacy and safety of NOACs-based anticoagulant therapy in the treatment of LVT subsequent to STEMI. TRIAL REGISTRATION: The EARLY-MYO-LVT trial (Clinical trial number: NCT03764241).

Preliminary study on the mechanism of acupoint injection of bone marrow mesenchymal stem cells in improving blood flow in the rat of hind limb ischemia.

OBJECTIVE: To explore the mechanism of acupoint injection of bone marrow mesenchymal stem cells (BM-MSCs) in improving blood flow in the rat with hind limb ischemia. METHODS: Twenty-four SD rats were randomly divided into 4 groups: normal control group (n = 6), model group (n = 6), BM-MSCs acupoint injection group (AI group, n = 6) and BM-MSC intramuscular injection group (MI group, n = 6). Sanyinjiao (SP 6), Housanli (ST 36), Zhaohai (KI 6), Huantiao (GB 30) and Yanglingquan (GB 34) were selected for the AI group, and five non-acupoints were selected on gastrocnemius and adductor of ischemic hind limbs in the MI group. BM-MSCs were injected to the latter two groups. The rat hind limb ischemia model was established with the method of blocking the femoral artery and its branches. Three weeks after injection of BM-MSCs, in each group, hindlimb adductor and gastrocnemius were taken from the ischemic side. Expressions of vascular endothelial growth factor (VEGF) and transfer growth factor-beta1 (TGF-beta1) in the skeletal muscle were determined with immunohistochemical method, and the small arteries in the skeletal muscle were labeled with alpha-SMA immunohistochemical staining method, the density of small arteries (number of arterioles/number of muscle fibers) and the number of the blood vessel with VEGF positive expression were calculated. The serum levels of VEGF and nitric oxide (NO) were detected. RESULTS: Compared with the model group, the expression of VEGF and TGF-beta1, and the density of small arteries and the number of VEGF-positive blood vessels in the AI group and the MI group significantly increased (both P < 0.01). Compared with the MI group, the density of small arteries and the number of VEGF-positive blood vessels in the AI group significantly increased (both P < 0.01); Compared with the model group and the normal control group, the serum expression quantity of NO and VEGF in the AI group and the MI group were significantly increased (P < 0.01). CONCLUSIONS: Acuppoint injection of BM-MSCs secrets more VEGF, TGF-beta1 and NO to increase angiogenesis and arteriogenesis, so as to improve blood flow of the rats of hind limb ischemic.

[Effect of acupoint injection with bone marrow mesenchymal stem cells on the blood flow in rats with hind limb ischemia].

OBJECTIVE: To investigate the best injection method of the bone marrow mesenchymal stem cells (BM-MSCs) transplantation for the treatment of a rat model with hind limb ischemia. METHODS: Twenty four SD rats with hind limb ischemia were randomly divided into four groups: control group, model group, acupoint BM-MSCs injection group (API group) and thigh muscle BM-MSCs injection group (TMI group). The acupoints of "Sanyinjiao" (SP 6), "Housanli" (ST 36), "Zhaohai" (KI 6), "Huantiao" (GB 30) and "Yanglingquan" (GB 34) were selected for API group, and five non-acupoints were selected on gastrocnemius and adductor of ischemic hind limb for TMI group. Both groups were accepted BM-MSCs transplantion. Model rat with hind limb ischemia was established with the method of blocking the femoral artery and its branches. The changes of blood flow (perfuse unit, PU) was monitored with laser Doppler flowmetry (LDF). In order to describe the visual changes in blood flow, the PU index (PUI) was determined as the ratio of ischemic to non-ischemic hind limb blood perfusion. And also, the levels of VEGF,bFGF in serum were tested to analyze the immunohistochemical expression quantity of VEGF and bFGF. RESULTS: Comparing with the model and the TMI groups, the PUI value on 3rd, 14th and 21th days after BM-MSCs transplantation were significantly increased in the API group (P < 0.05, P < 0.01). In contrast to the model group, the VEGF,bFGF levels in serum and the immunohistochemical expression quantity of VEGF and bFGF in the API and TMI groups were significantly increased (all P < 0.01). CONCLUSION: Transplantation of BM-MSCs through the acupoint can more significantly and quickly increase the blood flow and cause the greater improvement on hind limb ischemia than that of through the way of muscle injection.