bluuebunny/crossref_metadata_2025 huggingface dataset:
Cardiomyocyte Death Induced by Myocardial Ischemia and Reperfusion
Authors: Dumont Ewald A. W. J. , Hofstra Leo , van Heerde Waander L. , van den Eijnde Stephan , Doevendans Pieter A. F. , DeMuinck Ebo , Daemen Marc A. R. C. , Smits Jos F. M. , Frederik Peter , Wellens Hein J. J. , Daemen Mat J. A. P. , Reutelingsperger Chris P. M.
Published: June 2012

Introduction
—Phosphatidylserine (PS) externalization is regarded as one of the earliest hallmarks of cells undergoing programmed cell death. We studied the use of labeled human recombinant annexin-V, a protein selectively binding to PS, to detect cardiomyocyte death in an in vivo mouse model of cardiac ischemia and reperfusion (I/R).

Methods and Results
—I/R was induced in mouse hearts by ligation and subsequent release of a suture around the left anterior descending coronary artery. Annexin-V (25 mg/kg) fused to a marker molecule was injected intra-arterially 30 minutes before euthanasia. After 15 minutes of ischemia followed by 30 minutes of reperfusion, 1.4±1.2% (mean±SD) of the cardiomyocytes in the area at risk were annexin-V positive (n=6). This increased to 11.4±1.9% after 15 minutes of ischemia followed by 90 minutes of reperfusion (n=7) and to 20.2±3.3% after 30 minutes of ischemia followed by 90 minutes of reperfusion (n=7). In control mice, including those injected with annexin-V at the binding site of PS, no annexin-V–positive cells were observed. DNA gel electrophoresis showed typical laddering starting after 15 minutes of ischemia followed by 30 minutes of reperfusion, suggesting activation of the cell death program. Intervention in the cell death program by pretreatment with a novel Na
+
-H
+
exchange inhibitor substantially decreased annexin-V–positive cardiomyocytes from 20.2% to 2.2% in mice after 30 minutes of ischemia followed by 90 minutes of reperfusion.

Conclusions
—These data suggest that labeled annexin-V is useful for in situ detection of cell death in an in vivo model of I/R in the heart and for the evaluation of cell death–blocking strategies.
Therapeutic Angiogenesis With Recombinant Fibroblast Growth Factor-2 Improves Stress and Rest Myocardial Perfusion Abnormalities in Patients With Severe Symptomatic Chronic Coronary Artery Disease
Authors: Udelson James E. , Dilsizian Vasken , Laham Roger J. , Chronos Nicolas , Vansant John , Blais Michel , Galt James R. , Pike Marilyn , Yoshizawa Carl , Simons Michael
Published: June 2012

Background
—We report the effects of the administration of recombinant fibroblast growth factor-2 (rFGF-2) protein on myocardial perfusion using single photon emission computed tomography imaging in humans with advanced coronary disease.

Methods and Results
—A total of 59 patients with coronary disease that was not amenable to mechanical revascularization underwent intracoronary (n=45) or intravenous (n=14) administration of rFGF-2 in ascending doses. Changes in perfusion were evaluated at baseline and again at 29, 57, and 180 days after rFGF-2 administration. In this uncontrolled study, perfusion scans were analyzed by 2 observers who were blinded to patient identity and test sequence; scans were displayed in random order, with scans from nonstudy patients randomly interspersed to enhance blinding. Combining all dose groups, a reduction occurred in the per-segment reversibility score (reflecting the magnitude of inducible ischemia) from 1.7±0.4 at baseline to 1.1±0.6 at day 29 (
P
<0.001), 1.2±0.7 at day 57 (
P
<0.001), and 1.1±0.7 at day 180 (
P
<0.001). The 37 patients with evidence of resting hypoperfusion had evidence of improved resting perfusion: their per-segment rest perfusion score of 1.5±0.5 at baseline decreased to 1.0±0.8 at day 29 (
P
<0.001), 1.0±0.8 at day 57 (
P
=0.003), and 1.1±0.9 at day 180 (
P
=0.11).

Conclusions
—These preliminary data suggest that the administration of rFGF-2 to patients with advanced coronary disease resulted in an attenuation of stress-induced ischemia and an improvement in resting myocardial perfusion; these findings are consistent with a favorable effect of therapeutic angiogenesis.
Elevated Troponin I Level on Admission Is Associated With Adverse Outcome of Primary Angioplasty in Acute Myocardial Infarction
Authors: Matetzky Shlomo , Sharir Tali , Domingo Michelle , Noc Marko , Chyu Kuang-Yuh , Kaul Sanjay , Eigler Neal , Shah Prediman K. , Cercek Bojan
Published: June 2012

Background
—In patients with acute myocardial infarction (AMI) undergoing thrombolytic therapy, an elevated troponin level on admission is associated with a lower reperfusion rate and a complicated clinical course. Whether an elevated troponin level on admission similarly predicts an adverse outcome in patients undergoing primary angioplasty is currently unknown and was investigated in the present study.

Methods and Results
—Cardiac troponin I (cTnI) was determined on admission in 110 consecutive patients with AMI associated with ST-segment elevation or left bundle branch block who underwent primary angioplasty. Fifty-four patients (49%) had an elevated cTnI (≥0.4 ng/mL) on admission. In patients with elevated cTnI, primary angioplasty was less likely to achieve TIMI 3 flow (as classified by the Thrombolysis in Myocardial Infarction trial) in univariate (76% versus 96%,
P
=0.03) or in multivariate (odds ratio 0.1, 95% CI 0.02 to 0.54) analysis. Patients with elevated cTnI were more likely to develop congestive heart failure (23% versus 9%,
P
<0.05) and death, heart failure, or shock (30% versus 9%,
P
=0.006). Elevated cTnI remained a significant predictor of the composite end point after controlling for other clinical data that were available early in the course, including time to presentation and angiographic results (relative risk 5.2, 95% CI 1.03 to 26.3). During a follow-up of 426±50 days, elevated admission cTnI was a predictor of cardiac mortality (11% versus 0%,
P
=0.012), adverse cardiac events (cardiac mortality or nonfatal reinfarction; 19% versus 5.4%,
P
=0.04), and adverse cardiac events plus target vessel revascularization (32% versus 14%,
P
=0.054).

Conclusions
—In patients with ST-segment elevation AMI, an elevated cTnI on admission is associated with an increased risk of primary angioplasty failure and a more complicated clinical course.
Cardiac-Specific Overexpression of Tumor Necrosis Factor-α Causes Oxidative Stress and Contractile Dysfunction in Mouse Diaphragm
Authors: Li Xia , Moody Melanie R. , Engel David , Walker Stacey , Clubb Fred J. , Sivasubramanian Natarajan , Mann Douglas L. , Reid Michael B.
Published: June 2012

Background
—We have developed a transgenic mouse with cardiac-restricted overexpression of tumor necrosis factor-α (TNF-α). These mice develop a heart failure phenotype characterized by left ventricular dysfunction and remodeling, pulmonary edema, and elevated levels of TNF-α in the peripheral circulation from cardiac spillover. Given that TNF-α causes atrophy and loss of function in respiratory muscle, we asked whether transgenic mice developed diaphragm dysfunction and whether contractile losses were caused by oxidative stress or tissue remodeling.

Methods and Results
—Muscles excised from transgenic mice and littermate controls were studied in vitro with direct electrical stimulation. Cytosolic oxidant levels were measured with 2′,7′-dichlorofluorescin diacetate; emissions of the oxidized product were detected by fluorescence microscopy. Force generation by the diaphragm of transgenic animals was 47% less than control (13.2±0.8 [±SEM] versus 25.1±0.6 N/cm
2
;
P
<0.001); this weakness was associated with greater intracellular oxidant levels (
P
<0.025) and was partially reversed by 30-minute incubation with the antioxidant
N
-acetylcysteine 10 mmol/L (
P
<0.01). Exogenous TNF-α 500 μmol/L increased oxidant production in diaphragm of wild-type mice and caused weakness that was inhibited by
N
-acetylcysteine, suggesting that changes observed in the diaphragm of transgenic animals were mediated by TNF-α. There were no differences in body or diaphragm weights between transgenic and control animals, nor was there evidence of muscle injury or apoptosis.

Conclusions
—Elevated circulating levels of TNF-α provoke contractile dysfunction in the diaphragm through an endocrine mechanism thought to be mediated by oxidative stress.
Survival Outcomes 1 Year After Reperfusion Therapy With Either Alteplase or Reteplase for Acute Myocardial Infarction
Authors: Topol Eric J. , Ohman E. Magnus , Armstrong Paul W. , Wilcox Robert , Skene Alan M. , Aylward Philip , Simes John , Dalby Anthony , Betriu Amadeo , Bode Christoph , White Harvey D. , Hochman Judith S. , Emanuelson Hakan , Vahanian Alec , Sapp Shelly , Stebbins Amanda , Moliterno David J. , Califf Robert M.
Published: June 2012

Background
—New recombinant plasminogen activators have been developed to simulate the fibrinolytic action of the physiological serine protease tissue plasminogen activator (alteplase, t-PA), and have prolonged half-life features permitting bolus administration. One such activator, reteplase (r-PA), was compared with t-PA in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO)-III Trial.

Methods and Results
—At 1-year follow-up, survival status was ascertained in 97.4% of the 15 059 patients enrolled in the GUSTO-III trial. At 1 year, the mortality rate for the t-PA–assigned group was 11.06%, and for r-PA it was 11.20% (
P
=0.77). The absolute mortality difference of 0.14% has 95% CIs of −1.21% to 0.93%. There were no significant differences in outcome by intention-to-treat for the 2 different plasminogen activators in the prespecified groups (age, infarct location, time-to-treatment). The absolute difference in mortality rates between t-PA and r-PA progressively narrowed over the predetermined observation times after random assignment; it was 0.31% at 24 hours, 0.26% at 7 days, 0.23% at 30 days, and 0.14% at 1 year. Of note, mortality rate in the trial between 30 days and 1 year in 13 883 patients was 4.02% and did not differ between the treatment groups. However, this mortality rate was substantially greater than in GUSTO-I, in which mortality rate for t-PA versus streptokinase between 30 days and 1-year was 2.97% (heart rate 1.36, 95% CI 1.23, 1.50,
P
<0.001).

Conclusions
—The r-PA and t-PA strategies yielded similar survival outcomes after 30 days in this trial. The increase in mortality rate during extended follow-up compared with previous trials may reflect higher-risk patients and highlights the need for improved secondary prevention strategies.
Independent and Incremental Prognostic Value of
201
Tl Lung Uptake at Rest in Patients With Severe Postischemic Left Ventricular Dysfunction
Authors: Marcassa Claudio , Galli Michele , Baroffio Claudio , Eleuteri Ermanno , Campini Riccardo , Giannuzzi Pantaleo
Published: June 2012

Background
—An elevated
201
Tl lung uptake after stress is related to an adverse prognosis.

Methods and Results
—The functional and prognostic significance of resting
201
Tl lung uptake was assessed in 124 consecutive patients with ischemic heart disease and ejection fraction ≤35% undergoing rest-redistribution tomography to evaluate myocardial viability.
201
Tl lung uptake significantly correlated with pulmonary wedge pressure (
r
=0.66;
P
<0.01) and with a restrictive physiology by Doppler echocardiography (
P
<0.001). During a 13±13-month follow-up, 13 patients died and 23 patients required hospitalization as the result of worsening heart failure or nonfatal myocardial infarction (cumulative events rate 29%). Patients with events had a significantly higher
201
Tl lung/heart ratio (L/H) (
P
<0.001). A L/H value >0.61 best separated patients with and without events (ROC area under curve 0.82). Event-free survival was significantly lower in patients with L/H >0.61 (
P
<0.001); L/H >0.61 (χ
2
=10.8;
P
<0.001) and a restrictive filling pattern (χ
2
=3.6;
P
<0.05) were independent predictors of events. The prognostic value of L/H was incremental over that obtained by clinical, echographic and Doppler data (global χ
2
=20.8).

Conclusions
—In patients with severe postischemic left ventricular dysfunction undergoing rest-redistribution
201
Tl imaging, an increased lung tracer uptake showed incremental prognostic value over clinical and other imaging findings, providing clinically useful risk assessment.
Effect of Pravastatin on Coronary Disease Events in Subgroups Defined by Coronary Risk Factors
Authors: Sacks Frank M. , Tonkin Andrew M. , Shepherd James , Braunwald Eugene , Cobbe Stuart , Hawkins C. Morton , Keech Anthony , Packard Christopher , Simes John , Byington Robert , Furberg Curt D.
Published: June 2012

Background
—Previous trials have had insufficient numbers of coronary events to address definitively the effect of lipid-modifying therapy on coronary heart disease in subgroups of patients with varying baseline characteristics.

Methods and Results
—The data from 3 large randomized trials with pravastatin 40 mg were pooled and analyzed with the use of a prospectively defined protocol. Included were 19 768 patients, 102 559 person-years of follow-up, 2194 primary end points (coronary death or nonfatal myocardial infarction), and 3717 expanded end points (primary end point, CABG, or PTCA). Pravastatin significantly reduced relative risk in younger (<65 years) and older (≥65 years) patients, men and women, smokers and nonsmokers, and patients with or without diabetes or hypertension. The relative effect was smaller, but absolute risk reduction was similar in patients with hypertension compared with those without hypertension. Relative risk reduction was significant in predefined categories of baseline lipid concentrations. Tests for interaction were not significant between relative risk reduction and baseline total cholesterol (5% to 95% range 177 to 297 mg/dL, 4.6 to 7.7 mmol/L), HDL cholesterol (27 to 58 mg/dL, 0.7 to 1.5 mmol/L), and triglyceride (74 to 302 mg/dL, 0.8 to 3.4 mmol/L) concentrations, analyzed as continuous variables. However, for LDL cholesterol, the probability values for interaction were 0.068 for the prespecified primary end point and 0.019 for the expanded end point. Relative risk reduction was similar throughout most of the baseline LDL cholesterol range (125 to 212 mg/dL, 3.2 to 5.5 mmol/L) with the possible exception of the lowest quintile of CARE/LIPID (<125 mg/dL) (relative risk reduction 5%, 95% CI 19% to −12%).

Conclusions
—Pravastatin treatment is effective in reducing coronary heart disease events in patients with high or low risk factor status and across a wide range of pretreatment lipid concentrations.
Platelet Pl
A2
Allele and Incidence of Coronary Heart Disease
Authors: Aleksic Nena , Juneja Harinder , Folsom Aaron R. , Ahn Chul , Boerwinkle Eric , Chambless Lloyd E. , Wu Kenneth K.
Published: June 2012

Background
—The major platelet integrin glycoprotein IIb-IIIa plays a primary role in platelet aggregation and acute thrombus formation at the site of vascular injury. A genetic polymorphism of glycoprotein IIb-IIIa (Pl
A
) has recently been proposed as a potential genetic factor linking to platelet hyperaggregability and increased risk of myocardial infarction. Despite numerous, mostly nonprospective studies, the role of this polymorphism as a clinically relevant, inherited risk factor for coronary heart disease (CHD) is still controversial. The purpose of this study was to determine whether Pl
A2
is a risk factor for incident CHD and whether it is correlated with increased platelet activation in a case-cohort study nested within a prospective epidemiologic investigation.

Methods and Results
—Blood samples were collected and processed from the Atherosclerosis Risk in Communities Study cohort at the baseline examination (1987 to 1989). They were stored at −80°C. Pl
A1/A2
genotype and plasma β-thromboglobulin levels were determined in 439 incident CHD cases and a reference cohort sample of 544 (of whom 18 were also CHD cases). The prevalence of the Pl
A2
allele was not different in cases versus noncases. No significant correlation between CHD risk factors and the Pl
A2
allele was noted either. Platelet activation, as measured by plasma β-thromboglobulin levels, was not enhanced in individuals with the Pl
A2
allele.

Conclusions
—This prospective study indicates that healthy individuals carrying the Pl
A2
allele do not have an increased risk of CHD.
Cytomegalovirus Seropositivity and C-Reactive Protein Have Independent and Combined Predictive Value for Mortality in Patients With Angiographically Demonstrated Coronary Artery Disease
Authors: Muhlestein Joseph B. , Horne Benjamin D. , Carlquist John F. , Madsen Troy E. , Bair Tami L. , Pearson Robert R. , Anderson Jeffrey L.
Published: June 2012

Background
—The role of inflammation in coronary artery disease (CAD) is being increasingly recognized. Markers of inflammation (eg, C-reactive protein [CRP]) and infection (eg, seropositivity to
Chlamydia pneumoniae
, cytomegalovirus [CMV], and
Helicobacter pylori
) have been proposed as risk factors for CAD, but these associations require further evaluation.

Methods and Results
—We prospectively tested whether CRP levels and IgG seropositivity to
C pneumoniae
, CMV, and
H pylori
are predictors of subsequent mortality in 985 consecutive patients with angiographically demonstrated CAD (stenosis ≥70%). Patients were followed for an average of 2.7 years (range 1.5 to 4.0 years). Patients averaged 65 years of age; 77% were men; and 110 (11.2%) died during follow-up. CRP levels were significantly elevated in nonsurvivors compared with survivors (mean CRP 3.1 mg/dL versus 1.5 mg/dL,
P
=0.003). After controlling for all known baseline variables, the 2nd and 3rd tertiles of CRP compared with the 1st produced a Cox hazard ratio (HR) for mortality of 2.4 (
P
=0.001). Of the 3 infectious markers tested, only seropositivity to CMV (HR=1.9,
P
<0.05) was predictive of mortality. The majority of mortality risk associated with elevated CRP or CMV seropositivity occurred when both risk factors were present (
P
for trend <0.0001). Other independent predictors of increased risk of mortality were age (HR=1.07 per year,
P
<0.0001), left ventricular ejection fraction (HR=0.97 per percent,
P
<0.0001), and diabetes mellitus (HR=1.7,
P
=0.02).

Conclusions
—CMV seropositivity and elevated CRP, especially when in combination, are strong, independent predictors of mortality in patients with CAD. This suggests an interesting hypothesis that a chronic, smoldering infection (CMV) might have the capacity to accelerate the atherothrombotic process.
P-Selectin Expression on Platelets Determines Size and Stability of Platelet Aggregates
Authors: Merten Michael , Thiagarajan Perumal
Published: June 2012

Background
—P-selectin mediates rolling of platelets and leukocytes on activated endothelial cells. After platelet activation, P-selectin is translocated from intracellular granules to the external membrane, whereas fibrinogen aggregates platelets by bridging glycoprotein (GP) IIb/IIIa between adjacent platelets.

Methods and Results
—In this study, we define a novel role for P-selectin in platelet aggregation. Expression of P-selectin on the platelet surface correlated strongly with the mean platelet aggregate size. Inhibition of P-selectin binding to its ligand by either monoclonal anti–P-selectin antibodies directed against the lectin domain or soluble human P-selectin reversed platelet aggregation even when added up to 5 minutes after activation; however, fibrinogen binding to platelets was not affected. This deaggregating effect significantly reduced the maximal size and number of platelet aggregates. When added 1 minute after platelet activation, anti–P-selectin antibody achieved 95% to 100% of the deaggregating effect of EDTA, whereas the anti-GP IIb/IIIa antibody abciximab had no effect. Monoclonal antibodies against known P-selectin ligands, such as P-selectin GP ligand-1 (PSGL-1) or GP Ib, had no effect on platelet aggregation, suggesting a different ligand for P-selectin in platelet aggregate stabilization. In kinetic studies, P-selectin was maximally expressed 10 minutes after platelet activation, whereas maximal activation of GP IIb/IIIa occurred within the first 10 seconds, suggesting that P-selectin operates after fibrinogen binding to activated GP IIb/IIIa.

Conclusions
—These results indicate that P-selectin interaction with a ligand, different from PSGL-1 or GP Ib, stabilizes initial GP IIb/IIIa–fibrinogen interactions, allowing the formation of large stable platelet aggregates.
A Matrix Metalloproteinase Induction/Activation System Exists in the Human Left Ventricular Myocardium and Is Upregulated in Heart Failure
Authors: Spinale Francis G. , Coker Mytsi L. , Heung Lena J. , Bond Brian R. , Gunasinghe Himali R. , Etoh Takuma , Goldberg Aron T. , Zellner James L. , Crumbley A. Jackson
Published: June 2012

Background
—Matrix metalloproteinases (MMPs) contribute to matrix remodeling in disease states such as tumor metastases. Extracellular matrix metalloproteinase inducer (EMMPRIN) has been reported to increase MMP expression, and membrane-type MMP or MT1-MMP has been implicated to activate MMPs. The present study examined whether and to what degree EMMPRIN and MT1-MMP were expressed in human left ventricular (LV) myocardium as well as the association with MMP activity and expression in dilated cardiomyopathy (DCM).

Methods and Results
—LV myocardial zymographic MMP activity increased by >2-fold with both nonischemic DCM (n=21) and ischemic DCM (n=16) compared with normal (n=13). LV myocardial abundance of MMP-9 was increased with both forms of DCM. MMP-2 and MMP-3 were increased with nonischemic DCM. MMP-1 levels were decreased with both forms of DCM. EMMPRIN increased by >250% and MT1-MMP increased by >1000% with both forms of DCM.

Conclusions
—Increased LV myocardial MMP activity and selective upregulation of MMPs with nonischemic and ischemic forms of DCM occurred. Moreover, a local MMP induction/activation system was identified in isolated normal human LV myocytes that was upregulated with DCM. The control of MMP activation and expression in the failing human LV myocardium represents a new and potentially significant therapeutic target for this disease process.
Angiotensin II Induces Leukocyte–Endothelial Cell Interactions In Vivo Via AT
1
and AT
2
Receptor–Mediated P-Selectin Upregulation
Authors: Piqueras Laura , Kubes Paul , Alvarez Angeles , O’Connor Enrique , Issekutz Andrew C. , Esplugues Juan V. , Sanz Maria-Jesus
Published: June 2012

Background
—Angiotensin II (Ang II) plays a critical role in the development of vascular lesions in hypertension, atherosclerosis, and several renal diseases. Because Ang II may contribute to the leukocyte recruitment associated with these pathological states, the aim of the present study was to assess the role of Ang II in leukocyte–endothelial cell interactions in vivo.

Methods and Results
—Intravital microscopy of the rat mesenteric postcapillary venules was used. Sixty minutes of superfusion with 1 nmol/L Ang II induced a significant increase in leukocyte rolling flux (83.8±20.7 versus 16.4±3.1 cells/min), adhesion (11.4±1.0 versus 0.8±0.5 cells/100 μm), and emigration (4.0±0.7 versus 0.2±0.2 cells/field) without any vasoconstrictor activity. These effects were not mediated by mast cell activation. Intravenous pretreatment with AT
1
(losartan) or AT
2
(PD123,319) receptor antagonists significantly reduced Ang II–induced responses. A combination of both receptor antagonists inhibited the leukocyte rolling flux, adhesion, and extravasation elicited by Ang II at 60 minutes. Pretreatment of animals with fucoidin or an adhesion-blocking anti–rat P-selectin monoclonal antibody abolished Ang II–induced leukocyte responses. Furthermore, rat platelet P-selectin expression was not affected by Ang II stimulation.

Conclusions
—Ang II induces significant leukocyte rolling, adhesion, and emigration, which may contribute not only to hypertension but also to the onset and progression of the vascular damage associated with disease states in which plasma levels of this peptide are elevated.
Enhanced Ca
2+
Release and Na/Ca Exchange Activity in Hypertrophied Canine Ventricular Myocytes
Authors: Sipido Karin R. , Volders Paul G. A. , de Groot S. H. Marieke , Verdonck Fons , Van de Werf Frans , Wellens Hein J. J. , Vos Marc A.
Published: June 2012

Background
—Ventricular arrhythmias are a major cause of sudden death in patients with heart failure and hypertrophy. The dog with chronic complete atrioventricular block (CAVB) has biventricular hypertrophy and ventricular arrhythmias and is a useful model to study underlying cellular mechanisms. We investigated whether changes in Ca
2+
homeostasis are part of the contractile adaptation to CAVB and might contribute to arrhythmogenesis.

Methods and Results
—In enzymatically isolated myocytes, cell shortening, Ca
2+
release from the sarcoplasmic reticulum (SR), and SR Ca
2+
content were enhanced at low stimulation frequencies. Ca
2+
influx through L-type Ca
2+
channels was unchanged, but Ca
2+
influx via the Na/Ca exchanger was increased and contributed to Ca
2+
loading of the SR. Inward Na/Ca exchange currents were also larger. Changes in Ca
2+
fluxes were less pronounced in the right versus left ventricle.

Conclusions
—Enhanced Na/Ca exchange activity may improve contractile adaptation to CAVB but at the same time facilitate arrhythmias by (1) increasing the propensity to Ca
2+
overload, (2) providing more inward current leading to (nonhomogeneous) action potential prolongation, and (3) enhancing (arrhythmogenic) currents during spontaneous Ca
2+
release.
Olive Phenol Hydroxytyrosol Prevents Passive Smoking–Induced Oxidative Stress
Authors: Visioli Francesco , Galli Claudio , Plasmati Elena , Viappiani Serena , Hernandez Alicia , Colombo Claudio , Sala Angelo
Published: June 2012

Background
—Oxidative stress is involved in the onset of several degenerative disorders, and epidemiological studies indicate that a high intake of dietary antioxidants, as in the case of the Mediterranean basin, is protective. Olive mill waste waters (OMWWs) are a byproduct of olive oil production rich in phenolic antioxidants, such as hydroxytyrosol. We tested the effects of a low dose of an OMWW extract in a model of sidestream smoke–induced oxidative stress in rats by evaluating the urinary excretion of 8-iso-prostaglandin (PG) F
2α
(iPF
2α
-III).

Methods and Results
—An OMWW extract (5 mg/kg, providing 414 μg/kg of hydroxytyrosol) was administered to rats daily for 4 days, during which time the animals were exposed to sidestream smoke for 20 minutes once a day. Daily urines were collected, and the urinary excretion of 8-iso-PGF
2α
was evaluated as an index of oxidative stress–induced in vivo lipid peroxidation. The exposure of rats to passive smoking increased the urinary excretion of 8-iso-PGF
2α
by 44±4.2% at 48 hours and by 55±10% at 96 hours. Treatment with the OMWW extract was able to completely prevent the increase at 48 hours and resulted in lower increments (34±18% versus 55±10%) of 8-iso-PGF
2α
excretion at 96 hours.

Conclusions
—A low dose of hydroxytyrosol, administered through OMWW, reduces the consequences of sidestream smoke–induced oxidative stress in rats.
Endothelial Dysfunction of Coronary Resistance Arteries Is Improved by Tetrahydrobiopterin in Atherosclerosis
Authors: Tiefenbacher Christiane P. , Bleeke Tina , Vahl Christian , Amann Kerstin , Vogt Achim , Kübler Wolfgang
Published: June 2012

Background
—Tetrahydrobiopterin (BH4), an essential cofactor for the synthesis of NO, improves endothelial dysfunction after ischemia/reperfusion. Therefore, we hypothesized that reduction of BH4 is involved in the attenuation of endothelium-dependent vasodilation in atherosclerosis, and we investigated the effect of alterations of the BH4 level on the vasodilatory potential of coronary resistance vessels from humans and pigs with atherosclerosis.

Methods and Results
—Coronary arterioles were obtained from patients undergoing CABG (atherosclerosis group) or valve replacement (control group) and from pigs fed either a standard diet (control group) or atherogenic diet (atherosclerosis group). After isolation, vessels were cannulated, pressurized, and placed on the stage of an inverted microscope. Dose-response curves were investigated in response to the endothelium-dependent agonists histamine, serotonin, and acetylcholine (for pigs, substance P) and to the endothelium-independent agonist sodium nitroprusside (SNP) under control conditions and before and after incubation of the vessels with sepiapterin (substrate for BH4 synthesis). In vessels from patients and from animals with atherosclerosis, compared with vessels from the control groups, there was a significant (
P
<0.05) reduction of vasodilation to all tested endothelium-dependent agonists but not to SNP. After application of sepiapterin, the responses to the endothelium-dependent agonists but not to SNP were significantly improved in vessels from the atherosclerosis groups. Sepiapterin did not influence vascular reactivity in the control groups.

Conclusions
—Atherosclerosis severely compromises endothelial function of coronary resistance arteries. Administration of sepiapterin leads to a significant improvement of endothelium-dependent vasodilatation to different agonists in vessels from humans and pigs with atherosclerosis. Therefore, we conclude that a reduced availability of BH4 is involved in the development of endothelial dysfunction in atherosclerosis.
Coronary Composition and Macrophage Infiltration in Atherectomy Specimens From Patients With Diabetes Mellitus
Authors: Moreno Pedro R. , Murcia Alvaro M. , Palacios Igor F. , Leon Miltiadis N. , Bernardi Victor H. , Fuster Valentín , Fallon John T.
Published: June 2012

Background
—Lipid-rich, inflamed atherosclerotic lesions are associated with plaque rupture and thrombosis, which are the most important causes of death in patients with diabetes mellitus. This study was designed to quantify lipid composition and macrophage infiltration in the coronary lesions of patients with diabetes mellitus.

Methods and Results
—A total of 47 coronary atherectomy specimens from patients with diabetes mellitus were examined and compared with 48 atherectomy specimens from patients without diabetes. Plaque composition was characterized by trichrome staining. Macrophage infiltration was characterized by immunostaining. Clinical and demographic data were similar in both groups. The percentage of total area occupied by lipid-rich atheroma was larger in specimens from patients with diabetes (7±2%) than in specimens from patients without diabetes (2±1%;
P
=0.01), and the percentage of total area occupied by macrophages was larger in specimens from patients with diabetes (22±3%) than in specimens from patients without diabetes (12±1%;
P
=0.003). The incidence of thrombus was also higher in specimens from patients with diabetes than in specimens from patients without diabetes (62% versus 40%;
P
=0.04). Plaque composition, macrophage infiltration, and thrombus were similar in lesions from diabetic patients treated with insulin compared with lesions from patients treated with sulfonylureas or diet.

Conclusions
—Coronary tissue from patients with diabetes exhibits a larger content of lipid-rich atheroma, macrophage infiltration, and subsequent thrombosis than tissue from patients without diabetes. These differences suggest an increased vulnerability for coronary thrombosis in patients with diabetes mellitus.
Acute Hemodynamic and Clinical Effects of Levosimendan in Patients With Severe Heart Failure
Authors: Slawsky Mara T. , Colucci Wilson S. , Gottlieb Stephen S. , Greenberg Barry H. , Haeusslein Ernest , Hare Joshua , Hutchins Steven , Leier Carl V. , LeJemtel Thierry H. , Loh Evan , Nicklas John , Ogilby David , Singh Bramah N. , Smith William
Published: June 2012

Background
—We determined the short-term hemodynamic and clinical effects of levosimendan, a novel calcium-sensitizing agent, in patients with decompensated heart failure.

Methods and Results
—One hundred forty-six patients with New York Heart Association functional class III or IV heart failure (mean left ventricular ejection fraction 21±1%) who had a pulmonary capillary wedge pressure ≥15 mm Hg and a cardiac index ≤2.5 L · min
−1
· m
−2
were enrolled in a multicenter, double-blind, placebo-controlled study and randomized 2:1 to intravenous infusion of levosimendan or placebo. Drug infusions were uptitrated over 4 hours from an initial infusion rate of 0.1 μg · kg
−1
· min
−1
to a maximum rate of 0.4 μg · kg
−1
· min
−1
and maintained at the maximal tolerated infusion rate for an additional 2 hours. Levosimendan caused dose-dependent increases in stroke volume and cardiac index beginning with the lowest infusion rate and achieving maximal increases in stroke volume and cardiac index of 28% and 39%, respectively. Heart rate increased modestly (8%) at the maximal infusion rate and was not increased at the 2 lowest infusion rates. Levosimendan caused dose-dependent decreases in pulmonary capillary wedge, right atrial, pulmonary arterial, and mean arterial pressures. Levosimendan appeared to improve dyspnea and fatigue, as assessed by the patient and physician, and was not associated with a significant increase in adverse events.

Conclusions
—Levosimendan caused rapid dose-dependent improvement in hemodynamic function in patients with decompensated heart failure. These hemodynamic effects appeared to be accompanied by symptom improvement and were not associated with a significant increase in the number of adverse events. Levosimendan may be of value in the short-term management of patients with decompensated heart failure.
Peripheral Arterial Disease in Randomized Trial of Estrogen With Progestin in Women With Coronary Heart Disease
Authors: Hsia Judith , Simon Joel A. , Lin Feng , Applegate William B. , Vogt Molly T. , Hunninghake Donald , Carr Margaret
Published: June 2012

Background
—Postmenopausal estrogen use has been associated with reduced carotid atherosclerosis in observational studies, but this relationship has not been confirmed in a clinical trial. The impact of estrogen on atherosclerotic disease in other peripheral arteries is unknown.

Methods and Results
—Postmenopausal women with coronary heart disease (CHD) and an intact uterus (n=2763) were randomly assigned to conjugated equine estrogens (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg) daily or to placebo in a secondary CHD prevention trial. This analysis focuses on incident peripheral arterial procedures and deaths in the 2 treatment groups; peripheral vascular disease was a predefined secondary outcome. During a mean of 4.1 years of follow-up, 311 peripheral arterial events were reported in 213 women, an annual incidence of 2.9%. The number of women who had peripheral arterial events was 99 among those assigned to active estrogen/progestin and 114 among those assigned to placebo, a nonsignificant difference (relative hazard 0.87, 95% CI 0.66 to 1.14). In the placebo group, hypertension and diabetes mellitus were independently associated with higher rates of peripheral arterial events, and plasma HDL cholesterol and body mass index were associated with lower rates of peripheral arterial events. In the estrogen/progestin group, current smoking and diabetes were independent predictors of peripheral arterial events. Incident peripheral arterial disease was not a significant predictor of coronary, cardiovascular, or total mortality.

Conclusions
—Treatment with oral conjugated estrogen plus medroxyprogesterone acetate was not associated with a significant reduction in incident peripheral arterial events in postmenopausal women with preexisting CHD.
Photoangioplasty for Human Peripheral Atherosclerosis
Authors: Rockson Stanley G. , Kramer Paul , Razavi Mahmood , Szuba Andrzej , Filardo Steven , Fitzgerald Peter , Cooke John P. , Yousuf Shuja , DeVault Arthur R. , Renschler Markus F. , Adelman Daniel C.
Published: June 2012

Background
—In photoangioplasty, light activation of a photosensitive drug offers the potential for treatment of long segments of vascular disease. This is a brief description of a study designed to evaluate the safety and tolerability of a new photosensitizer, Antrin (motexafin lutetium), in the endovascular treatment of atherosclerosis.

Methods and Results
—An open-label, single-dose, escalating drug- and light-dose study was performed in patients with atherosclerotic peripheral arterial insufficiency. Clinical evaluation, serial quantitative angiography, and intravascular ultrasonography were performed. Therapy was well tolerated, and only minor side effects were observed. Treatment produced no deleterious vascular effects. Although this study was not designed to examine clinical efficacy, several secondary end points suggested a favorable therapeutic effect.

Conclusions
—This phase I study demonstrates that photoangioplasty with motexafin lutetium is well tolerated and safe. Preliminary efficacy data suggest a future role for the treatment of flow-limiting atherosclerosis.
Chlamydia pneumoniae
, Herpes Simplex Virus Type 1, and Cytomegalovirus and Incident Myocardial Infarction and Coronary Heart Disease Death in Older Adults
Authors: Siscovick David S. , Schwartz Stephen M. , Corey Lawrence , Grayston J. Thomas , Ashley Rhoda , Wang San-Ping , Psaty Bruce M. , Tracy Russell P. , Kuller Lewis H. , Kronmal Richard A.
Published: June 2012

Background
—Whether serological evidence of prior infection with
Chlamydia pneumoniae
, herpes simplex virus type 1 (HSV-1), and cytomegalovirus (CMV) is associated with myocardial infarction (MI) and coronary heart disease (CHD) death remains a source of controversy.

Methods and Results
—We conducted a nested case-control study among participants in the Cardiovascular Health Study, a cohort study of persons aged ≥65 years. Cases experienced an incident MI and CHD death (n=213). Control subjects were matched to cases by age, sex, clinic, year of enrollment, and month of blood draw (n=405). Serum was analyzed for IgG antibodies to
C pneumoniae
, HSV-1, and CMV. After adjustment for other risk factors, the risk of MI and CHD death was associated with the presence of IgG antibodies to HSV-1 (odds ratio [OR] 2.0, 95% CI 1.1 to 3.6) but was not associated with the presence of IgG antibodies to either
C pneumoniae
(OR 1.1, 95% CI 0.7 to 1.8) or CMV (OR 1.2, 95% CI 0.7 to 1.9). Although there was little association with low to moderate
C pneumoniae
antibody titers (≤1:512), high-titer (1:1024)
C pneumoniae
antibody was associated with an increased risk (OR 2.2, 95% CI 1.1 to 4.4).

Conclusions
—Among older adults, the presence of IgG antibodies to HSV-1 was associated with a 2-fold increase in the risk of incident MI and CHD death. For
C pneumoniae
, only high-titer IgG antibodies were associated with an increased risk of MI and CHD death. The presence of IgG antibodies to CMV was not associated with risk among the elderly.
Intracoronary Delivery of Adenovirus Encoding Adenylyl Cyclase VI Increases Left Ventricular Function and cAMP-Generating Capacity
Authors: Lai N. Chin , Roth David M. , Gao Mei Hua , Fine Suzanne , Head Brian P. , Zhu Jian , McKirnan M. Dan , Kwong Christopher , Dalton Nancy , Urasawa Kazushi , Roth David A. , Hammond H. Kirk
Published: June 2012

Background
—We tested the hypothesis that intracoronary injection of a recombinant adenovirus encoding adenylyl cyclase type VI (AC
VI
) would increase cardiac function in pigs.

Methods and Results
—Left ventricular (LV) dP/dt and cardiac output in response to isoproterenol and NKH477 stimulation were assessed in normal pigs before and 12 days after intracoronary delivery of histamine followed by intracoronary delivery of an adenovirus encoding lacZ (control) or AC
VI
(1.4×10
12
vp). Animals that had received AC
VI
gene transfer showed increases in peak LV dP/dt (average increase of 1267±807 mm Hg/s;
P
=0.0002) and cardiac output (average increase of 39±20 mL · kg
−1
· min
−1
;
P
<0.0001); control animals showed no changes. Increased LV dP/dt was evident 6 days after gene transfer and persisted for at least 57 days. Basal heart rate, blood pressure, and LV dP/dt were unchanged, despite changes in cardiac responsiveness to catecholamine stimulation. Twenty-three hour ECG recordings showed no change in mean heart rate or ectopic beats and no arrhythmias. LV homogenates from animals receiving AC
VI
gene transfer showed increased AC
VI
protein content (
P
=0.0007) and stimulated cAMP production (
P
=0.0006), confirming transgene expression and function; basal LV AC activity was unchanged. Increased cAMP-generating capacity persisted for at least 18 weeks (
P
<0.0002).

Conclusions
—Intracoronary injection of a recombinant adenovirus encoding AC provides enduring increases in cardiac function.
Shear Stress Downregulation of Platelet-Derived Growth Factor Receptor-β and Matrix Metalloprotease-2 Is Associated With Inhibition of Smooth Muscle Cell Invasion and Migration
Authors: Palumbo Roberta , Gaetano Carlo , Melillo Guido , Toschi Elena , Remuzzi Andrea , Capogrossi Maurizio C.
Published: June 2012

Background
—After endovascular injury, smooth muscle cells (SMCs) may be exposed to hemodynamic shear stress (SS), and these forces modulate neointima accumulation. The effect of SS on SMC migration and invasion is unknown, and it was examined in the present study.

Methods and Results
—Bovine aortic SMCs were exposed to laminar SS of 12 dyne/cm
2
for 3 (SS3) or 15 (SS15) hours; control (C3 and C15) SMCs were kept under static conditions. Platelet-derived growth factor (PDGF)-BB–directed SMC migration and invasion were evaluated by a modified Boyden chamber assay with filters coated with either gelatin or reconstituted basement membrane proteins (Matrigel), respectively. SS15 inhibited both SMC migration and invasion (
P
<0.0001). There was no significant difference between SS3 and C3 cells. Media conditioned with SS15 cells exhibited a reduction in matrix metalloprotease-2 (MMP-2) by zymography and Western analysis. Northern blot analysis revealed no effect of SS15 on MMP-2 mRNA. In contrast, SS15 decreased MMP-2 activator and membrane-type MMP (MT-MMP or MMP-14) mRNA and protein. Furthermore, SS15 decreased PDGF receptor-β (PDGF-Rβ) mRNA and protein (
P
<0.05), and the SS-dependent decrease in PDGF-BB–directed cell migration was rescued by overexpressing PDGF-Rβ.

Conclusions
—SS inhibits SMC migration and invasion via diminished PDGF-Rβ expression. This effect of SS is associated with decreased MMP-2 secretion and MT-MMP downregulation.
Improvement of von Willebrand Factor Proteolysis After Prostacyclin Infusion in Severe Pulmonary Arterial Hypertension
Authors: Veyradier Agnès , Nishikubo Toshiya , Humbert Marc , Wolf Martine , Sitbon Olivier , Simonneau Gérald , Girma Jean-Pierre , Meyer Dominique
Published: June 2012

Background
—The presence of dysfunctional von Willebrand factor (vWF) in pulmonary arterial hypertension (PAH) was suggested to be related to increased proteolysis.

Methods and Results
—In 10 patients with severe PAH, we studied the proteolysis of plasma vWF (vWF levels, multimeric distribution, proteolytic pattern, and cleaving protease activity) and hemodynamic variables (mean pulmonary artery pressure, cardiac index, and total pulmonary vascular resistance) at baseline and 30 days after initiation of continuous prostacyclin infusion. At baseline, vWF levels were significantly increased, vWF proteolysis was excessive, and vWF-cleaving protease activity remained normal. These biological abnormalities were reversible and paralleled the improvement of hemodynamics under vasodilator treatment with prostacyclin.

Conclusions
—The excessive proteolysis of vWF in PAH is likely to be related to an increased susceptibility of vWF to proteases induced by high shear rates rather than to an enhanced release of enzymes.
Mental Stress Induces Transient Endothelial Dysfunction in Humans
Authors: Ghiadoni Lorenzo , Donald Ann E. , Cropley Mark , Mullen Michael J. , Oakley Gillian , Taylor Mia , O’Connor Georgina , Betteridge John , Klein Nigel , Steptoe Andrew , Deanfield John E.
Published: June 2012

Background
—Mental stress has been linked to increased morbidity and mortality in coronary artery disease and to atherosclerosis progression. Experimental studies have suggested that damage to the endothelium may be an important mechanism.

Methods and Results
—Endothelial function was studied in 10 healthy men (aged 50.4±9.6 years) and in 8 non–insulin-dependent diabetic men (aged 52.0±7.2 years). Brachial artery flow-mediated dilation (FMD, endothelium dependent) and response to 50 μg of sublingual glyceryl trinitrate (GTN, endothelium independent) were measured noninvasively by use of high-resolution ultrasound before and after (30, 90, and 240 minutes) a standardized mental stress test. The same protocol without mental stress was repeated on a separate occasion in the healthy men. In healthy subjects, FMD (5.0±2.1%) was significantly (
P
<0.01) reduced at 30 and 90 minutes after mental stress (2.8±2.3% and 2.3±2.4%, respectively) and returned toward normal after 4 hours (4.1±2.0%). Mental stress had no effect on the response to GTN. In the repeated studies without mental stress, FMD did not change. The diabetic subjects had lower FMD than did the control subjects (3.0±1.5% versus 5.0±2.1%, respectively;
P
=0.02) but showed no changes in FMD (2.7±1.1% after 30 minutes, 2.8±1.9% after 90 minutes, and 3.1±2.3% after 240 minutes) or GTN responses after mental stress.

Conclusions
—These findings suggest that brief episodes of mental stress, similar to those encountered in everyday life, may cause transient (up to 4 hours) endothelial dysfunction in healthy young individuals. This might represent a mechanistic link between mental stress and atherogenesis.
Investigation of Chronic Venous Insufficiency
Authors: Nicolaides A. N.
Published: June 2012

Abstract
—This consensus document provides an up-to-date account of the various methods available for the investigation of chronic venous insufficiency of the lower limbs (CVI), with an outline of their history, usefulness, and limitations. CVI is characterized by symptoms or signs produced by venous hypertension as a result of structural or functional abnormalities of veins. The most frequent causes of CVI are primary abnormalities of the venous wall and the valves and secondary changes due to previous venous thrombosis that can lead to reflux, obstruction, or both. Because the history and clinical examination will not always indicate the nature and extent of the underlying abnormality (anatomic extent, pathology, and cause), a number of diagnostic investigations have been developed that can elucidate whether there is calf muscle pump dysfunction and determine the anatomic extent and severity of obstruction or reflux. The difficulty in deciding which investigations to use and how to interpret the results has stimulated the development of this consensus document. The aim of this document was to provide an account of these tests, with an outline of their usefulness and limitations and indications of which patients should be subjected to the tests and when and of what clinical decisions can be made. This document was written primarily for the clinician who would like to learn the latest approaches to the investigation of patients with CVI and the new applications that have emerged from recent research, as well as for the novice who is embarking on venous research. Care has been taken to indicate which methods have entered the clinical arena and which are mainly used for research. The foundation for this consensus document was laid by the faculty at a meeting held under the auspices of the American Venous Forum, the Cardiovascular Disease Educational and Research Trust, the European Society of Vascular Surgery, the International Angiology Scientific Activity Congress Organization, the International Union of Angiology, and the Union Internationale de Phlebologie at the Abbaye des Vaux de Cernay, France, on March 5 to 9, 1997. Subsequent input by co-opted faculty members and revisions in 1998 and 1999 have ensured a document that provides an up-to-date account of the various methods available for the investigation of CVI.