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.

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.