Relationship of left ventricular thrombus formation and adverse outcomes in acute anterior myocardial infarction in patients treated with primary percutaneous coronary intervention.

BACKGROUND: The incidence of left ventricular thrombus (LVT) is 4% to 15% in patients with anterior acute ST-segment elevation myocardial infarction (ant-AMI) in the era of primary percutaneous coronary intervention (PPCI). And patients with LVT have higher in-hospital mortality. HYPOTHESIS: There is a relationship between LVT formation and 1-year major adverse cardio-cerebrovascular events (MACCE) in patients with ant-AMI treated by PPCI. METHODS: Our study population included 1488 consecutive patients with ant-AMI. The primary endpoint was the incidence of MACCE within 1 year after AMI. The secondary endpoint was the thrombosis disappearance. RESULTS: A total of 106 (7.1%) patients were diagnosed with LVT and 1382 (92.9%) patients without LVT. Patients with LVT had a higher incidence of MACCE than in patients without LVT (21.7%vs10.3%; P < 0.001). Univariate analysis showed LVT was associated with an increase in MACCE risk (odds ratio [OR] = 2.40; 95% confidence interval [CI] [1.37-4.21]; P < 0.001). When examining MACCE components individually, LVT was only associated with the incidence of congestive heart failure (OR = 2.41; 95% CI [1.29-4.58]; P = 0.001). After adjustment for principal confounders, LVT remained an independent risk factor for MACCE (HR = 2.28; 95% CI [1.12-6.38]; P = 0.020). Other independent predictors include 24-hour LVEF, creatine kinase peak value, and age. Further analysis found patients with LVT in international normalized ratio (INR) ≥ 2 group had lower MACCE risk and higher thrombus disappearance than in INR < 2 group (13.5%vs29.6%; P = 0.044; 90.4%vs74.1%; P = 0.029). CONCLUSION: For patients with ant-AMI treated by PPCI, LVT is an independent predictor of 1-year MACCE events. Treatment with vitamin K antagonist in the therapeutic range (INR ≥ 2) has the potential to reduce MACCE risk and promote disappearance of thrombus.

Optimal timing of staged percutaneous coronary intervention in ST-segment elevation myocardial infarction patients with multivessel disease.

BACKGROUND: Studies have shown that staged percutaneous coronary intervention (PCI) for non-culprit lesions is beneficial for prognosis of ST-segment elevation myocardial infarction (STEMI) patients with multivessel disease. However, the optimal timing of staged revascularization is still controversial. This study aimed to find the optimal timing of staged revascularization. METHODS: A total of 428 STEMI patients with multivessel disease who underwent primary PCI and staged PCI were included. According to the time interval between primary and staged PCI, patients were divided into three groups (≤ 1 week, 1-2 weeks, and 2-12 weeks after primary PCI). The primary endpoint was major adverse cardiovascular events (MACE), a composite of all-cause death, non-fatal re-infarction, repeat revascularization, and stroke. Cox regression model was used to assess the association between staged PCI timing and risk of MACE. RESULTS: During the follow-up, 119 participants had MACEs. There was statistical difference in MACE incidence among the three groups (≤ 1 week: 23.0%; 1-2 weeks: 33.0%; 2-12 weeks: 40.0%; P = 0.001). In the multivariable adjustment model, the timing interval of staged PCI ≤ 1 week and 1-2 weeks were both significantly associated with a lower risk of MACE [hazard ratio (HR): 0.40, 95% confidence intervals (CI): 0.24-0.65; HR: 0.54, 95% CI: 0.31-0.93, respectively], mainly attributed to a lower risk of repeat revascularization (HR: 0.41, 95% CI: 0.24-0.70; HR: 0.36, 95% CI: 0.18-0.7), compared with a strategy of 2-12 weeks later of primary PCI. CONCLUSIONS: The optimal timing of staged PCI for non-culprit vessels should be within two weeks after primary PCI for STEMI patients.

Triiodo-L-Thyronine Promotes the Maturation of Cardiomyocytes Derived From Rat Bone Marrow Mesenchymal Stem Cells.

Bone marrow mesenchymal stem cells (BMMSCs) can differentiate into cardiomyocytes and be used in cardiac tissue engineering for heart regeneration. However, the effective clinical application of cardiomyocytes derived from BMMSCs is limited because of their immature phenotype. The aim of this study was to investigate the potential of triiodo-L-thyronine (T3) to drive cardiomyocytes derived from BMMSCs to a more mature state. BMMSCs were divided into 3 groups: untreated controls, differentiated, and T3 treated. The differentiation potential was evaluated by immunofluorescence microscopy and flow cytometry. Data were represented as the numbers of cells positive for the troponin I (cTnI), α-actinin, GATA4, and the connexin-43 (Cx-43). The mRNA levels of these specific markers of cardiomyocytes were determined by quantitative real-time polymerase chain reaction. The levels of cardiomyocytes markers protein and octamer-binding transcription factor 4 (Oct-4) were determined by Western blot analyses. Our data demonstrate that T3 treatment leads to a significant increase in cells positive for cTnI, GATA4, Cx-43, and α-actinin. The mRNA and protein expression levels of these specific markers of cardiomyocytes were also increased after T3 treatment. At the same time, the protein expression level of Oct-4 was substantially downregulated in T3-treated cells. These results demonstrate that T3 treatment increases the differentiation of BMMSCs induced to cardiomyocytes and promotes their maturation.

Effect of beta-3 adrenoceptor stimulation on the levels of ApoA-I, PPARα, and PPARγ in apolipoprotein E-deficient mice.

The beta-3 adrenoceptor (ß3-AR) protects against the progression of atherosclerosis. However, the specific mechanism of this antiatherosclerotic effect is still not clear. Thus, the aim of this study was to understand the antiatherosclerotic effects of ß3-AR. Thirty-six male homozygous apolipoprotein E-deficient mice and wild-type C57BL/6J mice were randomized into 6 treatment groups: wild-type, atherosclerotic model, atorvastatin, low-dose ß3-AR agonist, high-dose ß3-AR agonist, and ß3-AR antagonist groups. The serum lipids, aortic-free cholesterol (FC), and cholesteryl ester (CE) concentrations were measured at the end of the treatments. The mRNA expression levels of liver apolipoprotein A-I (apoA-I), peroxisome proliferator-activated receptor-α (PPARα), and peroxisome proliferator-activated receptor-γ (PPARγ) were detected by quantitative real-time PCR. Protein expression levels of apoA1, PPARα, and PPARγ in the liver were determined by western blot analysis. Treatment with ß3-AR significantly increased the plasma levels of high-density lipoprotein cholesterol and apoA-I, whereas the levels of total cholesterol, triglycerides, and low-density lipoprotein cholesterol decreased. The ß3-AR agonist treatment markedly decreased both the FC and the CE concentrations in the aorta compared with the atherosclerotic model mice. The ß3-AR agonist increased the mRNA and protein expression levels of apoA-I, PPARα, and PPARγ in the liver. This study demonstrates that long-term ß3-AR activation can regulate lipid metabolic disorders and reduces the aortic FC and the CE concentrations. These effects may be related to apoA-I, PPARα, and PPARγ.

[Effects of immune modulation therapy on cardiac function in aged patients with chronic heart failure].

OBJECTIVE: To investigate the effect of immune modulation therapy on cardiac function and lymphocyte subsets in aged patients with chronic heart failure (CHF). METHODS: CHF (NYHA classification: II-IV) patients older than 60 years were randomly divided into two groups: CHF intervention group received regular therapy and thymopetide (2 mg/day i.m. for 75 days, n = 48), CHF control group received regular therapy (n = 48), 45 healthy individuals older than 60 years served as normal control. Left ventricular ejection faction of (LVEF), inner diameter of left ventricular end-diastole (LVEDD), inner diameter of left ventricular end-systole (LVESD), lymphocyte subsets, plasma high sensitive C-reactive protein (hsCRP), plasma brain natrium peptide (BNP) and 6 minutes walking distance (6MWT) were measured at before therapy, after the first course (15 days) of treatment and after the third course of treatment (75 days). RESULTS: (1) Before therapy, the levels of BNP, hsCRP, CD8 T cells, LVEDD and LVESD were significantly higher and the levels of CD3, CD4, CD19 T cells, NK, CD4/CD8 ratio, LVEF and 6MWT were significantly lower in CHF patients compared to compared normal controls (all P < 0.05). These parameters were similar between CHF intervention group and CHF control group. (2) At 15 days, the levels of CD3, CD4, CD19 T cells and NK were significantly increased (P < 0.05 or P < 0.01) while the level of CD8, BNP and hsCRP were significantly decreased (P < 0.05 or P < 0.01) in CHF intervention group compared with CHF control group. (3) At 75 days, the levels of CD3, CD4, CD19 T cells, NK, CD4/CD8, LVEF and 6MWT were significantly increased (P < 0.05 or P < 0.01) while the levels of CD8, BNP, hsCRP and Minnesota Living with Heart Failure Questionnaire (MLHFQ) were significantly decreased (P < 0.05 or P < 0.01) in CHF intervention group compared with CHF control group. CONCLUSION: Thymopetide, an immune modulating agent, might regulate the quantity and proportion of lymphocyte subsets and improve cardiac function in aged patients with CHF, indicating that immune modulation therapy might be a new treatment strategy for aged CHF patients.

Change of expression of renal alpha1-adrenergic receptor and angiotensin II receptor subtypes with aging in rats.

BACKGROUND AND AIMS: It has been considered that the functional decline of renal vasoconstriction during senescence is associated with an alteration in renal alpha1-adrenergic receptor (alpha1-AR) expression. While alterations in renal angiotensin II receptor (ATR) expression was considered to have an effect on renal structure and function, until now little information has been available concerning alpha1-AR and ATR expression variations over the entire aging continuum. The present study was undertaken to examine the expression levels of alpha1-AR and ATR subtypes in renal tissue during the spectrum running from young adulthood, to middle age, to the presenium, and to the senium. METHODS: Semiquantitative Reverse Transcription Polymerase Chain Reaction (RT-PCR) and Western Blot were used to quantify the messenger RNA (mRNA) and protein levels of alpha1-AR and ATR subtypes in renal tissue in 3-month-old (young adult), 12-month-old (middle age), 18-month-old (presenium) and 24-month-old (senium) Wistar rats. RESULTS: alpha1A-AR expression decreased gradually with aging: it was decreased during middle age, the presenium and the senium, compared, respectively, with young adult values (p<0.01), and there was a significant decline both in the presenium with respect to middle age and in the senium with respect to the presenium. alpha1B-AR and alpha1D-AR expression were unmodified during senescence. AT1R expression was unaffected by aging during young adulthood and middle age, but exhibited a remarkable downregulation in the presenium and senium periods (p<0.01). AT2R expression was markedly increased in the senium (p<0.01). CONCLUSIONS: These results suggest that there are considerable variations in the expression levels of renal alpha1-AR and ATR subtypes during aging. alpha1A-AR expression downregulation may account for the reduced reactivity of renal alpha1-AR to vasoconstrictors and to renal function decline in the senium. Both the downregulation of AT1R and the upregulation of AT2R may be influential in maintaining normal physiological renal function during aging.

Age-dependent differential crosstalk between alpha(1)-adrenergic and angiotensin receptors.

BACKGROUND: Previous reports of crosstalk between alpha(1)- adrenergic receptors (alpha(1)-AR) and angiotensin receptors (ATR) have pointed to the existence of physiological regulation between the sympathetic nervous system and the renin-angiotensin system at the receptor level. This regulation may have an important role in the control of blood pressure and may be modified in different cardiovascular pathologies. Aging is considered to be an independent cardiovascular risk factor. Nevertheless, neither the variation in physiological action or interaction of signal transduction between these two receptors as a result of aging has been established. To clarify these aspects, the interaction between alpha(1)-AR and ATR was evaluated. METHODS: The inotropic response of alpha(1)-AR to agonists was assessed in the presence and absence of angiotensin II using the left atria of 3.5-, 12-, 18- and 24-month-old (young adult, middle aged, elderly and aged, respectively) male Wistar rats. In the four age groups of rat hearts, the activities of tyrosine kinase were measured when just the AT(1)R subtype was activated, or when both alpha(1)-AR and AT(1)R were activated. The activities of cytosolic phospholipase A(2) and the levels of cyclic GMP were investigated when just the AT(2)R subtype was activated, or when both alpha(1)-AR and AT(2)R were activated. RESULTS: No effect was found on the cumulative concentration-response curve for phenylephrine when AT(1)R was activated in 3.5- or 12-month-old rats. However, in 18- and 24-month-old rats, the maximum positive inotropic response and the negative logarithm of the effective 50% concentration increased markedly. No effect was found on the cumulative concentration response curve induced by phenylephrine when AT(2)R was activated. The activities of tyrosine kinase increased significantly in 3.5- and 12-month-old rats, but there was no difference in 18- and 24-month-old rats when alpha(1)-AR and AT(1)R were both activated compared with when just AT(1)R was activated. Cytosolic phospholipase A(2) activity and cyclic GMP levels decreased significantly when both alpha(1)-AR and AT(2)R were activated compared with when just AT(2)R was activated. CONCLUSIONS: In the isolated left atria of elderly and aged rats, the activation of AT(1)R enhanced the positive inotropic response induced by the activation of alpha(1)-AR. The activation of AT(2)R had no effect on the positive inotropic response induced by the activation of alpha(1)-AR. The action of alpha(1)-AR increased the signal transduction of AT(1)R in young-adult and middle-aged rat hearts but had no effect in elderly and aged hearts. The action of alpha(1)-AR had no effect on AT(2)R signal transduction.

Interaction of signal transduction between angiotensin AT1 and AT2 receptor subtypes in rat senescent heart.

BACKGROUND: Angiotensin II (Ang II) acting at angiotensin AT(1) receptor (AT(1)R) has well documented effects on cardiovascular structure such as the promotion of cardiovascular hypertrophy and fibrosis, which are believed to be opposed by angiotensin AT(2) receptor (AT(2)R) stimulation. The expressions of AT(1)R and AT(2)R are up-regulated in senescent hearts. The purpose of this study was to investigate the interaction of signal transduction between AT(1)R and AT(2)R, and to detect whether there is any difference in the interaction in rat hearts of different age. METHODS: In 3.5-, 12-, 18- and 24-month-old rats, the heart cell membrane activities of protein kinase C (PKC) and tyrosine kinase were measured when AT(1)R and AT(2)R were both activated by Ang II or just the AT(1)R was activated by Ang II and PD123319. The activities of cytosolic phospholipase A(2) (cPLA(2)) and the levels of cGMP were investigated when AT(1)R and AT(2)R were both activated by Ang II or just the AT(2)R was activated by Ang II and losartan. RESULTS: When AT(1)R and AT(2)R were both activated compared to when the AT(1)R was activated, the activities of PKC were not different in hearts from 3.5- and 12-month-old rats, but decreased significantly in 18- and 24-month-old rats; the activities of tyrosine kinase were not different in 3.5-month-old rats but decreased significantly in 12-, 18- and 24-month-old rats. The activities of cPLA(2) were all decreased significantly in rats of different age when AT(1)R and AT(2)R were both activated compared to when the AT(2)R was activated. Treatment with Ang II alone compared to Ang II and losartan decreased the levels of cGMP (fmol/mg) in rats of different age (102.7 +/- 12.7 versus 86.0 +/- 8.0 in 3.5-month-old rats, P < 0.05; 81.0 +/- 9.4 versus 70.0 +/- 6.3 in 12-month-old rats, P < 0.05; 69.8 +/- 5.6 versus 54.2 +/- 5.3 in 18-month-old rats, P < 0.01; 57.7 +/- 8.0 versus 39.0 +/- 3.0 in 24-month-old rats, P < 0.01). CONCLUSIONS: The activation of AT(1)R inhibited the signal transduction of AT(2)R during the aging variation, and the activation of AT(2)R inhibited the signal transduction of AT(1)R in rat heart of different age.