Effects of valsartan on fibrinolysis in hypertensive patients with metabolic syndrome.

BACKGROUND: The purpose of this study was to analyze the effect of valsartan on abnormal adipocyte metabolism and prothrombotic state in hypertensive patients with metabolic syndrome (MetS). METHODS AND RESULTS: We conducted a multicenter, prospective, randomized, parallel-group controlled trial in 150 hypertensive patients with MetS. They were randomly assigned to receive either 80-160 mg valsartan per day (valsartan group, n=79) or other conventional treatment without a renin-angiotensin system (RAS) inhibitor (non-RAS inhibitor group, n=71). After 1 year, there were no significant differences between the 2 groups in the changes in systolic and diastolic blood pressures (valsartan: 153±15/86±15 to 138±16/77±12 mmHg; non-RAS inhibitor: 150±14/82±15 to 137±15/76±10 mmHg). There was a significant difference in the change in the levels of plasminogen activator inhibitor-1 (PAI-1) between the 2 groups after 1 year (valsartan: 3.7±3.2 ng/ml; non-RAS inhibitor: 5.8±3.3 ng/ml, P=0.04). There was no significant difference between groups in the change in the concentration of adiponectin after 1 year (valsartan: 0.3±0.4 µg/ml; non-RAS inhibitor: 0.9±0.4 µg/ml, P=0.22). The animal study showed aortic PAI-1 protein expression was reduced in double knockout mice of angiotensin II type 1a receptor and apolipoprotein E (apoE) compared with the apoE knockout mice. CONCLUSIONS: Valsartan reduced plasma PAI-1 levels compared to non-RAS inhibitor in hypertensive patients with MetS, which suggests it may be useful for improving fibrinolytic function.

Noninvasive evaluation of coronary reperfusion by CT angiography in patients with STEMI.

OBJECTIVES: The aim of this study was to determine whether 64-slice multidetector computed tomography (MDCT) can differentiate coronary reperfusion with Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 from TIMI flow grade ≤ 2 after ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Multidetector computed tomography has become a popular modality for noninvasive coronary artery imaging. Recently, 64-slice MDCT has been applied to evaluate coronary arteries in acute coronary artery disease. METHODS: The presence or absence of distal reperfusion in infarct-related arteries (IRA) was visualized with 64-slice MDCT during the acute phase in 87 non-high-risk patients after STEMI. To differentiate TIMI flow grade 3 from TIMI flow grade 2, we calculated the computed tomography (CT) number ratio by dividing the CT number of the contrast-enhanced coronary lumen at the most distal IRA by that at the proximal site to the culprit lesion in patients with reperfusion on MDCT. The MDCT findings were compared with TIMI flow grade with invasive coronary angiography (ICA) performed 20 ± 5 min later. RESULTS: According to ICA, 58 patients had TIMI flow grade 0 or 1, 17 had TIMI flow grade 2, and 12 had TIMI flow grade 3, whereas distal reperfusion was evident on MDCT in 28 of the 29 patients with TIMI flow grade ≥ 2 and absent in 55 of the 58 with TIMI flow grade ≤ 1. The CT number ratio was significantly higher in TIMI flow grade 3 than in TIMI flow grade ≤ 2 (0.64 ± 0.11 vs. 0.37 ± 0.12; p < 0.0001). The sensitivity, specificity, and accuracy of a diagnosis of TIMI flow grade 3 on the basis of a CT number ratio of ≥ 0.54 that was an optimal cutoff value determined by receiver-operator characteristic curve analysis were 92%, 97%, and 97%, respectively. CONCLUSIONS: Visualization of the IRA by 64-slice MDCT enables noninvasive differentiation of angiographic TIMI flow grade 3 from TIMI flow grade ≤ 2 coronary reperfusion during the acute phase in patients with STEMI.

Different effects of propranolol, phenylephrine, and saline volume loading on catecholamine-induced left ventricular outflow tract obstruction in acute coronary syndrome.

Hemodynamic deterioration due to left ventricular outflow tract (LVOT) obstruction can occur during catecholamine infusion in patients with acute coronary syndrome (ACS). The purpose of the present study was to compare the utility of propranolol, phenylephrine infusion, and rapid saline loading for reversal of dobutamine-induced LVOT obstruction in a canine model of ACS. ACS was induced via left anterior descending artery ligation in 21 open-chest anesthetized dogs, and LVOT obstruction, defined as an LVOT gradient > 30 mmHg, was induced by dobutamine infusion (20 to 40 microg/kg/min). Subsequently, the effects of propranolol infusion (0.7 to 1.0 microg/kg/min, n = 8), phenylephrine infusion (10 to 200 microg/kg/min, n = 7), and saline loading (200 to 400 mL/hr, n = 6) were assessed by serial hemodynamic measurements. All interventions produced significant and comparable improvements in the LVOT pressure gradient (propranolol: 60 +/- 16 to 15 +/- 12; phenylephrine: 68 +/- 15 to 12 +/- 10; saline loading: 58 +/- 18 to 22 +/- 10 mmHg; P < 0.001 for baseline versus postintervention; P = NS for comparison between interventions). Phenylephrine produced the greatest elevation in aortic pressure (propranolol: +15 +/- 13; phenylephrine: +51 +/- 36; saline loading: +15 +/- 15 mmHg; P < 0.05), while saline loading produced the greatest increase in cardiac output (propranolol: +0.05 +/- 0.12; phenylephrine: +0.28 +/- 0.37; saline loading: +0.73 +/- 0.48 L/min; P < 0.05). Propranolol was the only intervention that produced a significant decrease in diastolic pulmonary artery pressure (16 +/- 5 to 11 +/- 3 mmHg, P < 0.05). Propranolol, phenylephrine infusion, and saline volume loading were similarly effective in reversing dobutamine-induced LVOT obstruction in this canine model of ACS. However, each intervention produced different hemodynamic effects with potentially different clinical indications.

Crossover from classical to quantum behavior of the Duffing oscillator through a pseudo-Lyapunov-exponent.

We discuss the quantum-classical correspondence (QCC) in a specific dissipative chaotic system, the Duffing oscillator. The quantum version of the Duffing oscillator is treated as an open quantum system and analyzed numerically by the use of quantum state diffusion (QSD). We consider a pseudo-Lyapunov exponent and investigate it in detail, varying the Planck constant effectively. We show that there exists a critical stage in which the crossover from classical to quantum behavior occurs. Furthermore, we find that a dissipation effect suppresses the occurrence of chaos in the quantum region, while it, combined with the periodic external force, plays a crucial role in the chaotic behavior of the classical system.