bluuebunny/crossref_metadata_2025 huggingface dataset:
Adenoviral Gene Transfer of Activated Phosphatidylinositol 3′-Kinase and Akt Inhibits Apoptosis of Hypoxic Cardiomyocytes In Vitro
Authors: Matsui Takashi , Li Ling , Federica del Monte  , Fukui Yasuhisa , Franke Thomas F. , Hajjar Roger J. , Rosenzweig Anthony
Published: June 2012

Background
—The intracellular signaling pathways that control cardiomyocyte apoptosis have not been fully defined. Because insulin-like growth factor-1 (IGF-1) prevents cardiomyocyte apoptosis, we examined the role of its downstream signaling molecules in an in vitro model of hypoxia-induced cardiomyocyte apoptosis.

Methods and Results
—Treatment of rat neonatal cardiomyocytes with IGF-1 increased activity of both phosphatidylinositol 3′ (PI 3)-kinase and its downstream target, Akt (also known as protein kinase B or PKB). Cardiomyocytes were subjected to hypoxia for 24 hours, and apoptosis was assessed by DNA laddering, TUNEL staining, and ELISA for histone-associated DNA fragments. IGF-1 treatment (100 nmol/L) reduced cardiomyocyte apoptosis, and this effect was inhibited by simultaneous treatment with a PI 3-kinase inhibitor. Cardiomyocytes were infected with either a control adenovirus (Ad.EGFP) or adenoviruses carrying constitutively active forms of PI 3-kinase (Ad.BD110) or Akt (Ad.myr-Akt-HA). Ad.BD110 significantly inhibited apoptosis of hypoxic cardiomyocytes compared with Ad.EGFP (61.0±4.6% less DNA fragmentation than in Ad.EGFP-infected cells,
P
<0.0001). Ad.myr-Akt-HA even more dramatically inhibited apoptosis of hypoxic cardiomyocytes (90.9±1.4% less DNA fragmentation than in controls,
P
<0.0001).

Conclusions
—IGF-1 activates PI 3-kinase and Akt in cardiomyocytes. Activated PI 3-kinase and Akt are each sufficient to protect hypoxic cardiomyocytes against apoptosis in vitro. Adenoviral gene transfer provides a useful tool for investigating the role of these signaling pathways in cardiomyocyte apoptosis.
Calcineurin Plays a Critical Role in Pressure Overload–Induced Cardiac Hypertrophy
Authors: Shimoyama Masaki , Hayashi Doubun , Takimoto Eiki , Zou Yunzeng , Oka Toru , Uozumi Hiroki , Kudoh Sumiyo , Shibasaki Futoshi , Yazaki Yoshio , Nagai Ryozo , Komuro Issei
Published: June 2012

Background
—Cardiac hypertrophy is a fundamental adaptive response to hemodynamic overload; how mechanical load induces cardiac hypertrophy, however, remains elusive. It was recently reported that activation of a calcium-dependent phosphatase, calcineurin, induces cardiac hypertrophy. In the present study, we examined whether calcineurin plays a critical role in pressure overload–induced cardiac hypertrophy.

Methods and Results
—Pressure overload produced by constriction of the abdominal aorta increased the activity of calcineurin in the rat heart and induced cardiac hypertrophy, including reprogramming of gene expression. Treatment of rats with a calcineurin inhibitor, FK506, inhibited the activation of calcineurin and prevented the pressure overload–induced cardiac hypertrophy and fibrosis without change of hemodynamic parameters. Load-induced expression of immediate-early-response genes and fetal genes was also suppressed by the FK506 treatment.

Conclusions
—The present results suggest that the calcineurin signaling pathway plays a pivotal role in load-induced cardiac hypertrophy and may pave the way for a novel pharmacological approach to prevent cardiac hypertrophy.
Downregulation of Delayed Rectifier K
+
Currents in Dogs With Chronic Complete Atrioventricular Block and Acquired Torsades de Pointes
Authors: Volders Paul G. A. , Sipido Karin R. , Vos Marc A. , Spätjens Roel L. H. M. G. , Leunissen Jet D. M. , Carmeliet Edward , Wellens Hein J. J.
Published: June 2012

Background
—Acquired QT prolongation enhances the susceptibility to torsades de pointes (TdP). Clinical and experimental studies indicate ventricular action potential prolongation, increased regional dispersion of repolarization, and early afterdepolarizations as underlying factors. We examined whether K
+
-current alterations contribute to these proarrhythmic responses in an animal model of TdP: the dog with chronic complete atrioventricular block (AVB) and biventricular hypertrophy.

Methods and Results
—The whole-cell K
+
currents
I
TO1
,
I
K1
,
I
Kr
, and
I
Ks
were recorded in left (LV) and right (RV) ventricular midmyocardial cells from dogs with 9±1 weeks of AVB and controls with sinus rhythm.
I
TO1
density and kinetics and
I
K1
outward current were not different between chronic AVB and control cells.
I
Kr
had a similar voltage dependence of activation and time course of deactivation in chronic AVB and control.
I
Kr
density was similar in LV myocytes but smaller in RV myocytes (−45%) of chronic AVB versus control. For
I
Ks
, voltage-dependence of activation and time course of deactivation were similar in chronic AVB and control. However,
I
Ks
densities of LV (−50%) and RV (−55%) cells were significantly lower in chronic AVB than control.

Conclusions
—Significant downregulation of delayed rectifier K
+
current occurs in both ventricles of the dog with chronic AVB. Acquired TdP in this animal model with biventricular hypertrophy is thus related to intrinsic repolarization defects.
Optimizing the Percutaneous Interventional Outcomes for Patients With Diabetes Mellitus
Authors: Marso Steven P. , Lincoff A. Michael , Ellis Stephen G. , Bhatt Deepak L. , Tanguay Jean-Francois , Kleiman Neal S. , Hammoud Talal , Booth Joan E. , Sapp Shelly K. , Topol Eric J.
Published: June 2012

Background
—Stenting likely decreases the need for target-vessel revascularization procedures in diabetic patients compared with balloon angioplasty. However, the efficacy of stenting with platelet glycoprotein IIb/IIIa blockade has not yet been assessed in diabetics.

Methods and Results
—We analyzed the outcomes of 491 diabetic patients within the multicenter Evaluation of Platelet IIb/IIIa Inhibitor for Stenting Trial (EPISTENT). Diabetic patients were a prospectively defined subset: 173 were randomized to stent-placebo, 162 to stent-abciximab, and 156 to balloon angioplasty–abciximab. The main end point for this analysis was combined 6-month death, myocardial infarction (MI), or target-vessel revascularization (TVR). The composite end point occurred in 25.2% of stent-placebo, 23.4% of balloon-abciximab, and 13.0% of stent-abciximab patients (
P
=0.005). Abciximab therapy, irrespective of revascularization strategy (stent or balloon angioplasty), resulted in a significant reduction in the 6-month death or MI rate: 12.7% for stent-placebo, 7.8% for balloon angioplasty–abciximab, and 6.2% for the stent-abciximab group (
P
=0.029). The 6-month TVR rate was 16.6% for stent-placebo, 18.4% for balloon-abciximab, and 8.1% for stent-abciximab (
P
=0.021). Compared with stent-placebo, stent-abciximab therapy was associated with a significant increase in angiographic net gain (0.88 versus 0.55 mm;
P
=0.011) and a decrease in the late loss index (0.40 versus 0.60 mm;
P
=0.061). The 1-year mortality rate for diabetics was 4.1% for stent-placebo and 1.2% for stent-abciximab patients (
P
=0.11).

Conclusions
—The combination of stenting and abciximab therapy among diabetics resulted in a significant reduction in 6-month rates of death, MI, and TVR compared with stent-placebo or balloon-abciximab therapy.
Effects of Intracoronary Radiation on Thrombosis After Balloon Overstretch Injury in the Porcine Model
Authors: Vodovotz Yoram , Waksman Ron , Kim Won-Ho , Bhargava Balram , Chan Rosanna C. , Leon Martin
Published: June 2012

Background
—The main complications of PTCA remain thrombosis and restenosis. Recent studies have demonstrated reduction in the neointimal hyperplasia after intracoronary radiation (IR) with doses of 10 to 25 Gy of ionizing radiation delivered by either β- or γ-emitters to injured vessels. The purpose of this study was to examine the effect of ionizing radiation on the thrombosis rate (TR) of injured porcine coronary arteries.

Methods and Results
—Thirty-four juvenile swine (63 coronary arteries) were subjected to overstretch balloon injury followed by IR with doses of 0 to 18 Gy of either β- or γ-radiation. Two weeks after treatment, tissue sections were perfusion-fixed, stained with hematoxylin-eosin and Verhoeff–van Gieson’s stain, and analyzed for presence of a thrombus, thrombus morphology, and neointima formation by computer-assisted histomorphometry techniques. Although the overall TR increased dose-dependently from 0 to 18 Gy prescribed dose, luminal thrombi decreased. Thrombus area also decreased with increasing radiation dose, whether assessed at the prescription point or at the luminal surface, which corresponded to decreased intimal area. Furthermore, luminal thrombi present after IR tended to consist mostly of fibrin and thus were less organized than in controls.

Conclusions
—These results suggest that IR induces thrombosis but does not necessarily compromise the lumen. Strategies for reducing TR may further decrease intimal area as well as increasing the safety of this therapy.
Effects of Dobutamine on Coronary Stenosis Physiology and Morphology
Authors: Bartunek Jozef , Wijns William , Heyndrickx Guy R. , de Bruyne Bernard
Published: June 2012

Background
—The mechanisms leading to dobutamine-induced ischemia are not fully understood. In the present study, we investigated the effects of high-dose intravenous dobutamine on morphological and physiological indexes of coronary stenoses.

Methods and Results
—Twenty-two patients with normal left ventricular function and isolated coronary stenoses were studied. At catheterization, mean aortic pressure (P
a
), mean distal coronary pressure (P
d
), and P
d
/P
a
as an index of myocardial resistance were recorded at rest, after intracoronary adenosine, and during intravenous infusion of dobutamine (10 to 40 μg · kg
−1
· min
−1
). Reference vessel diameter and minimal luminal diameter, as assessed by coronary angiography, did not change during dobutamine infusion compared with baseline (2.84±0.49 versus 2.77±0.41 mm and 1.35±0.38 versus 1.27±0.31 mm, respectively; both
P
=NS). During peak dobutamine infusion, P
d
and P
d
/P
a
reached similar levels as during adenosine infusion (60±18 versus 59±18 mm Hg and 0.68±0.18 versus 0.68±0.17, respectively; all
P
=NS). In 9 patients, an additional bolus of intracoronary adenosine given at the peak dose of dobutamine failed to further decrease P
d
/P
a
. Furthermore, in patients with dobutamine-induced wall motion abnormalities, the maximal decrease in P
d
/P
a
was similar during dobutamine and adenosine infusions.

Conclusions
—High-dose intravenous infusion of dobutamine does not modify the dimensions of the epicardial coronary stenosis. However, much like the direct coronary vasodilator adenosine, dobutamine fully exhausts myocardial resistance regardless of the presence of mechanical dysfunction.
Clinical Potential of Intravascular Ultrasound for Physiological Assessment of Coronary Stenosis
Authors: Takagi Atsushi , Tsurumi Yukio , Ishii Yasuhiro , Suzuki Kazuhito , Kawana Masatoshi , Kasanuki Hiroshi
Published: June 2012

Background
—Little is known regarding intravascular ultrasound (IVUS) criteria to determine the functional severity of coronary stenosis. Recently, fractional flow reserve (FFR) has emerged as a lesion-specific index of the functional severity of a coronary stenosis that is independent of systemic hemodynamic variability. The present study was undertaken to determine the IVUS parameters for the physiological severity of coronary stenosis.

Methods and Results
—Fifty-one lesions in 42 patients were evaluated by means of quantitative coronary angiogram, IVUS, and intracoronary pressure measurements. The FFR was calculated as the ratio of the distal coronary pressure divided by the proximal coronary pressure under hyperemia. We considered a value of the FFR <0.75 as significant in determining inducible ischemia, according to the previous studies. The minimal luminal area (MLA) and the area stenosis were measured by IVUS. By regression analysis, the MLA showed a positive correlation with the FFR value (
r
2
=0.62,
P
<0.0001). The area stenosis had a significant inverse correlation with the value of FFR (
r
2
=0.60,
P
<0.0001). The IVUS thresholds that maximized the sensitivity and specificity were MLA <3.0 mm
2
(sensitivity, 83.0%; specificity, 92.3%) and area stenosis >0.6 (sensitivity, 92.0%; specificity, 88.5%). The combination of both criteria (MLA <3.0 mm
2
and area stenosis <0.6) without exception met a value of the FFR <0.75.

Conclusions
—Anatomic parameters obtained by IVUS showed a significant correlation to the FFR values. The present study demonstrated that the combination of the MLA and area stenosis measured by IVUS can be an anatomic predictor for the physiological impact of coronary epicardial stenosis.
Discoordinate Modulation of Natriuretic Peptides During Acute Cardiac Allograft Rejection in Humans
Authors: Masters Roy G. , Davies Ross A. , Veinot John P. , Hendry Paul J. , Smith Stuart J. , de Bold Adolfo J.
Published: June 2012

Background
—Increased circulating levels of the cardiac polypeptide hormones atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) may be observed after orthotopic cardiac transplantation. Both the hypertrophic and inflammatory processes in the allograft may contribute to this increase, but no mechanistic explanation has been suggested for this observation.

Methods and Results
—Plasma immunoreactive ANF and BNP determinations were performed in 10 consecutive transplant patients. These were correlated with degree of rejection as reflected by histopathological findings at serial endomyocardial biopsies. Three patients had associated hemodynamic measurements and blood samples 24 hours before and after transplantation. All rejection episodes that received treatment were accompanied by a marked increase in BNP plasma levels to >≈400 pg/mL. Steadily increasing BNP levels preceded overt rejection as assessed by histopathological criteria. The increase in plasma BNP was not always accompanied by an increase in ANF, which suggests the specific upregulation of BNP gene expression during acute rejection episodes. Treatment of the acute rejection episodes led to a substantial decrease of BNP plasma levels.

Conclusions
—The significant selective increase in plasma BNP levels found in the present study has not been previously described. This finding provides a new insight into the mechanism of allograft rejection and the modulation of natriuretic peptide synthesis and release. Furthermore, although preliminary, the data suggest that BNP plasma levels could form the basis for a new, noninvasive screening test to predict acute cardiac allograft rejection. Because treatment with the antilymphocyte monoclonal antibody OKT3 (murine monoclonal antibody to the CD3 antigen of the human T-cell) decreased BNP plasma levels, cytokine production by T-cells may mediate the selective increase in circulating BNP.
Efficacy and Safety of Ibutilide Fumarate for the Conversion of Atrial Arrhythmias After Cardiac Surgery
Authors: VanderLugt James T. , Mattioni Thomas , Denker Stephen , Torchiana David , Ahern Thomas , Wakefield Linda K. , Perry Kimberly T. , Kowey Peter R.
Published: June 2012

Background
—Atrial arrhythmias occur commonly after cardiac surgery and are a cause of significant morbidity and increased hospital costs, yet there is no well-studied treatment strategy to deal with them expeditiously. The purpose of this study was to determine the efficacy and safety of ibutilide fumarate, an approved drug for the rapid conversion of atrial fibrillation and flutter, in patients after cardiac surgery.

Methods and Results
—Patients with atrial fibrillation or flutter occurring 1 to 7 days after surgery and lasting 1 hour to 3 days were randomized to receive two 10-minute blinded infusions of placebo or 0.25, 0.5, or 1.0 mg of ibutilide fumarate. Treatment was considered successful if sinus rhythm was restored for any period of time by hour 1.5. A total of 302 patients were randomized, 201 with fibrillation and 101 with flutter. Treatment with ibutilide resulted in significantly higher conversion rates than placebo, and efficacy was dose related (placebo 15%; ibutilide 0.25 mg 40%, 0.5 mg 47%, and 1.0 mg 57%). Conversion rates at all doses were higher for atrial flutter than for atrial fibrillation. Mean time to conversion decreased as the dose was increased. Polymorphic ventricular tachycardia was the most serious adverse effect and occurred in 1.8% of the ibutilide-treated patients compared with 1.2% of patients who received placebo.

Conclusions
—Ibutilide is a useful and safe treatment alternative for the atrial arrhythmias that occur after cardiac surgery.
Elevated Serum Triglyceride Levels and Long-Term Mortality in Patients With Coronary Heart Disease
Authors: Haim Moti , Benderly Michal , Brunner Daniel , Behar Solomon , Graff Eran , Reicher-Reiss Henrietta , Goldbourt Uri
Published: June 2012

Background
—The association between elevated blood triglyceride levels and subsequent mortality risk in patients with established coronary heart disease (CHD) has been investigated rarely. The aim of the present study was to investigate this association.

Methods and Results
—We evaluated mortality over a mean follow-up time of 5.1 years among 9033 male and 2499 female CHD patients who were screened for participation in the Bezafibrate Infarction Prevention (BIP) Study. A stepwise increase in mortality with increasing serum triglyceride levels was observed in patients with desirable or elevated serum total cholesterol levels and in patients with either desirable or abnormally low HDL cholesterol levels. Multivariate adjustment for factors other than HDL cholesterol yielded a slightly increased adjusted mortality risk with a 1-natural-log-unit elevation of triglyceride levels in men (hazard ratio [HR] 1.14, 95% CI 1.00 to 1.30) and women (HR 1.37, 95% CI 1.04 to 1.88). Excess covariate-adjusted risk was noted among patients with elevated total and LDL cholesterol and in women with HDL cholesterol levels >45 mg/dL. After additional adjustment for HDL cholesterol, the risk of mortality with a 1-natural-log-unit elevation of triglycerides declined in men (HR 1.09, 95% CI 0.94 to 1.26) and in women (HR 1.10, 95% CI 0.80 to 1.50). A trend for increased mortality risk remained in patients with elevated total and LDL cholesterol and in women with HDL cholesterol >45 mg/dL.

Conclusions
—Elevated triglyceride levels were associated with a small, independent increased mortality risk in CHD patients. This risk may be increased among subgroups of patients with elevated total cholesterol and LDL cholesterol levels.
Cocaine Stimulates the Human Cardiovascular System via a Central Mechanism of Action
Authors: Vongpatanasin Wanpen , Mansour Yasser , Chavoshan Bahman , Arbique Debbie , Victor Ronald G.
Published: June 2012

Background
—Cocaine is thought to stimulate the cardiovascular system by blocking peripheral norepinephrine reuptake. This study was designed to test the novel hypotheses that cocaine also stimulates the human cardiovascular system by (1) increasing central sympathetic outflow, or (2) decreasing parasympathetic control of heart rate.

Methods and Results
—In 14 healthy cocaine-naive humans, we measured blood pressure, heart rate, and skin sympathetic nerve activity (SNA) with intraneural microelectrodes before, during, and for 90 minutes after intranasal cocaine (2 mg/kg, n=7) or lidocaine (2 mg/kg, n=7). Intranasal cocaine caused an initial but transient 3.3-fold increase in skin SNA during the period of intranasal administration followed by a sustained 2.4-fold increase lasting for up to 90 minutes after cocaine. Unlike cocaine, intranasal lidocaine caused only a small transient increase in skin SNA due to local nasal irritation. The cocaine-induced increase in SNA was accompanied by decreased skin blood flow, increased skin vascular resistance, and increased heart rate. In 11 additional subjects, we showed that the cocaine-induced increase in heart rate was eliminated by β-adrenergic receptor blockade (propranolol) but unaffected by muscarinic receptor blockade (atropine), indicating sympathetic mediation.

Conclusions
—These studies provide direct microneurographic evidence in humans that intranasal cocaine stimulates central sympathetic outflow. This central sympathetic activation appears to be targeted not only to the cutaneous circulation promoting peripheral vasoconstriction but also to the heart promoting tachycardia.
Developmental and Neurological Status of Children at 4 Years of Age After Heart Surgery With Hypothermic Circulatory Arrest or Low-Flow Cardiopulmonary Bypass
Authors: Bellinger David C. , Wypij David , Kuban Karl C. K. , Rappaport Leonard A. , Hickey Paul R. , Wernovsky Gil , Jonas Richard A. , Newburger Jane W.
Published: June 2012

Background
—It is not known whether developmental and neurological outcomes in the preschool period differ depending on whether the predominant vital organ support strategy used in infant heart surgery was total circulatory arrest (CA) or low-flow cardiopulmonary bypass.

Methods and Results
—Infants with D-transposition of the great arteries who underwent an arterial-switch operation were randomly assigned to a support method consisting predominantly of CA or low-flow cardiopulmonary bypass. Developmental and neurological status were evaluated blindly at 4 years of age in 158 of 163 eligible children (97%). Neither IQ scores nor overall neurological status were significantly associated with either treatment group or duration of CA. The CA group scored lower on tests of motor function (gross motor,
P
=0.01; fine motor,
P
=0.03) and had more severe speech abnormalities (oromotor apraxia,
P
=0.007). Seizures in the perioperative period, detected either clinically or by continuous electroencephalographic monitoring, were associated with lower mean IQ scores (12.6 and 7.7 points, respectively) and increased risk of neurological abnormalities (odds ratios, 8.4 and 5.6, respectively). The performance of the full cohort was below expectations in several domains, including IQ, expressive language, visual-motor integration, motor function, and oromotor control.

Conclusions
—Use of CA to support vital organs during open heart surgery in infancy is associated, at the age of 4 years, with worse motor coordination and planning but not with lower IQ or with worse overall neurological status.
Endothelial Growth Factor Receptors in Human Fetal Heart
Authors: Partanen Taina A. , Makinen Taija , Arola Johanna , Suda Toshio , Weich Herbert A. , Alitalo Kari
Published: June 2012

Background
—Endothelial receptor tyrosine kinases include 3 members of the vascular endothelial growth factor receptor (VEGFR) family and 2 members of the angiopoietin receptor (Tie) family. In addition, the VEGF
165
isoform binds to neuropilin-1 (NP-1), a receptor for collapsins/semaphorins. The importance of these receptors for vasculogenesis and angiogenesis has been shown in gene-targeted mice, but so far, little is known about their exact expression patterns in the human vasculature.

Methods and Results
—Frozen sections of human fetal heart were stained immunohistochemically with receptor-specific monoclonal (VEGFR, Tie) or polyclonal (NP-1) antibodies. The following patterns were observed: The endocardium was positive for VEGFR-1, VEGFR-2, NP-1, Tie-1, and Tie-2 but negative for VEGFR-3. The coronary vessels were positive for Tie-1, Tie-2, VEGFR-1, and NP-1 and negative for VEGFR-2 and VEGFR-3. Myocardial capillaries and epicardial blood vessels stained for VEGFR-1, VEGFR-2, NP-1, and Tie-1; myocardial capillaries and epicardial veins weakly for Tie-2; and epicardial lymphatic vessels for VEGFR-2 and VEGFR-3, weakly for Tie-1 and Tie-2, but not for VEGFR-1 or NP-1.

Conclusions
—The results demonstrate differential expression of the endothelial growth factor receptors in distinct types of vessels in the human heart. This information is useful for the understanding of their roles in physiological and pathological processes and for their diagnostic and therapeutic application in cardiovascular medicine.
Chymase-Dependent Angiotensin II Formation in Human Vascular Tissue
Authors: Takai Shinji , Jin Denan , Sakaguchi Masato , Miyazaki Mizuo
Published: June 2012

Background
—Some reports have suggested that, in vitro, human heart chymase in homogenates contributes little to angiotensin (Ang) II formation in the presence of natural protease inhibitors such as α-antitrypsin. We studied whether chymase bound to heparin, resembling an in vivo form, could contribute to Ang II formation in the presence of natural protease inhibitors.

Methods and Results
—The Ang II formation was increased time-dependently after incubation in an extract (1 mg of protein/mL) of human vascular tissues containing Ang I. The concentration of Ang II in the extract after incubation for 30 minutes was 1.67±0.06 nmol/mL, and we regarded this quantity of Ang II as 100%. The Ang II formation was inhibited 10%, 95%, and 96% by 1 μmol/L lisinopril, 100 μmol/L chymostatin, and 0.1 g/L α-antitrypsin, respectively. The extract was applied to a heparin affinity column. After the column was washed with PBS, the eluted PBS contained a weak Ang II-forming activity, which was completely inhibited by lisinopril. The eluted PBS, to which >0.8 mol/L NaCl had been added, showed a strong Ang II-forming activity which was inhibited by chymostatin and α-antitrypsin. After the application of the extract, the column was washed with PBS and then an Ang I solution in PBS was applied to the column. The Ang II formation in the PBS eluted from the incubated column was increased time-dependently. The concentration of Ang II in the PBS (1 mL) eluted from the column after incubation for 30 minutes was 2.56±0.28 nmol/mL, and we regarded this quantity of Ang II as 100%. To study the effects of inhibitors, the extract (1 mg of protein/mL) was applied to a heparin affinity column (1 mL) which was preequilibrated with PBS (3 mL); 100 μmol/L chymostatin or 0.1 g/L α-antitrypsin in PBS (1 mL) was then applied to the column. After the column was washed with PBS (3 mL), Ang I solution (1 mg/mL) in PBS was applied to the column, and the column was incubated for 30 minutes. The Ang II formation in the PBS eluted from the column was suppressed up to 5% by application of chymostatin, although this was not affected by application of α-antitrypsin.

Conclusions
—These findings suggest that human chymase bound to heparin plays a functional role in Ang II formation in the presence of natural protease inhibitors such as α-antitrypsin.
Atherogenic Dyslipidemia in HIV-Infected Individuals Treated With Protease Inhibitors
Authors: Périard Daniel , Telenti Amalio , Sudre Philippe , Cheseaux Jean-Jacques , Halfon Patricia , Reymond Marianne J. , Marcovina Santica M. , Glauser Michel P. , Nicod Pascal , Darioli Roger , Mooser Vincent
Published: June 2012

Background
—Administration of protease inhibitors (PIs) to HIV-infected individuals has been associated with hyperlipidemia. In this study, we characterized the lipoprotein profile in subjects receiving ritonavir, indinavir, or nelfinavir, alone or in combination with saquinavir.

Methods and Results
—Plasma lipoprotein levels were quantified in 93 HIV-infected adults receiving PIs. Comparison was done with pretreatment values and with 28 nonPI-treated HIV-infected subjects. An elevation in plasma cholesterol levels was observed in all PI-treated groups but was more pronounced for ritonavir (2.0±0.3 mmol/L [mean±SEM], n=46, versus 0.1±0.2 mmol/L in nonPI treated group,
P
<0.001) than for indinavir (0.8±0.2 mmol/L, n=26,
P
=0.03) or nelfinavir (1.2±0.2 mmol/L, n=21,
P
=0.01). Administration of ritonavir, but not indinavir or nelfinavir, was associated with a marked elevation in plasma triglyceride levels (1.83±0.46 mmol/L,
P
=0.002). Plasma HDL-cholesterol levels remained unchanged. Combination of ritonavir or nelfinavir with saquinavir did not further elevate plasma lipid levels. A 48% increase in plasma levels of lipoprotein(a) was detected in PI-treated subjects with pretreatment Lp(a) values >20 mg/dL. Similar changes in plasma lipid levels were observed in 6 children receiving ritonavir.

Conclusions
—Administration of PIs to HIV-infected individuals is associated with a marked, compound-specific dyslipidemia. The risk of pancreatitis and premature atherosclerosis due to PI-associated dyslipidemia remains to be established.
Hormone Replacement Therapy and Increased Plasma Concentration of C-Reactive Protein
Authors: Ridker Paul M. , Hennekens Charles H. , Rifai Nader , Buring Julie E. , Manson JoAnn E.
Published: June 2012

Background
—It has been hypothesized that postmenopausal hormone replacement therapy (HRT) may increase levels of C-reactive protein (CRP), a marker of inflammation associated with increased risk of future cardiovascular events. However, data evaluating this hypothesis are sparse and limited to older women.

Methods and Results
—CRP levels were evaluated in a cross-sectional survey of 493 healthy postmenopausal women; mean age was 51 years. Overall, median CRP levels were 2 times higher among women taking HRT than among women not taking HRT (0.27 versus 0.14 mg/dL;
P
=0.001). This difference was present in all subgroups evaluated, including those with no history of hypertension, hyperlipidemia, obesity, diabetes, or cigarette consumption or a family history of premature coronary artery disease (all
P
< 0.01). Compared with nonusers of HRT, median CRP levels were higher among women using estrogen alone (
P
=0.003) and women using estrogen plus progesterone (
P
=0.03); however, there was no significant difference in CRP levels between users of different HRT preparations. In multivariate analysis, the relationship between HRT use and CRP remained significant after control for body mass index, age, diabetes, hypertension, hyperlipidemia, alcohol use, and cigarette consumption (
P
=0.001).

Conclusions
—In this cross-sectional survey, CRP levels were increased among apparently healthy postmenopausal women taking HRT. The potential impact of HRT on inflammatory parameters should be investigated in ongoing clinical trials.
Increased Proinflammatory Cytokines in Patients With Chronic Stable Angina and Their Reduction By Aspirin
Authors: Ikonomidis Ignatios , Andreotti Felicita , Economou Emanouel , Stefanadis Christodoulos , Toutouzas Pavlos , Nihoyannopoulos Petros
Published: June 2012

Background
—Proinflammatory cytokines released by injured endothelium facilitate interaction of endothelial cells with circulating leukocytes and thus may contribute to development and progression of atherosclerosis. We investigated whether cytokines and C-reactive protein (CRP) are indicative of myocardial ischemia or of diseased vessels and whether they are influenced by aspirin treatment in patients with chronic stable angina.

Methods and Results
—Plasma macrophage colony stimulating factor (MCSF), IL-1b, IL-6, and CRP were measured in 60 stable patients after 48-hour Holter monitoring and in 24 matched controls. All patients had angiographic documentation of disease and positive exercise ECGs. Patients with ischemia on Holter monitoring (n=40) received aspirin or placebo in a 6-week, randomized, double blind, crossover trial. Blood sampling was repeated at the end of each treatment phase (3 weeks). Compared to controls, patients had more than twice median MCSF (800 versus 372 pg/mL), IL-6 (3.9 versus 1.7 pg/mL), and CRP (1.25 versus 0.23 mg/L) levels (
P
<0.01 for all comparisons). MCSF was related to ischemia on Holter monitoring (
P
<0.01), to low ischemic threshold during exercise (
P
<0.01), and together with IL-1b to number of diseased vessels (
P
<0.05). MCSF, IL-6, and CRP were all reduced after 6 weeks of aspirin treatment (
P
<0.05).

Conclusions
—These findings suggest that cytokines are associated with both ischemia and anatomic extent of disease in patients with stable angina. Reduced cytokine and CRP levels by aspirin may explain part of aspirin’s therapeutic action.
Effects of Autonomic Neuropathy on Coronary Blood Flow in Patients With Diabetes Mellitus
Authors: Di Carli Marcelo F. , Bianco-Batlles Daniela , Landa Maria E. , Kazmers Andris , Groehn Harvey , Muzik Otto , Grunberger George
Published: June 2012

Background
—Cardiac sympathetic signals play an important role in the regulation of myocardial perfusion. We hypothesized that sympathetically mediated myocardial blood flow would be impaired in diabetics with autonomic neuropathy.

Methods and Results
—We studied 28 diabetics (43±7 years old) and 11 age-matched healthy volunteers. PET was used to delineate cardiac sympathetic innervation with [
11
C]hydroxyephedrine ([
11
C]HED) and to measure myocardial blood flow at rest, during hyperemia, and in response to sympathetic stimulation by cold pressor testing. The response to cardiac autonomic reflex tests was also evaluated. Using ultrasonography, we also measured brachial artery reactivity during reactive hyperemia (endothelium-dependent dilation) and after sublingual nitroglycerin (endothelium-independent dilation). Based on [
11
C]HED PET, 13 of 28 diabetics had sympathetic-nerve dysfunction (SND). Basal flow was regionally homogeneous and similar in the diabetic and normal subjects. During hyperemia, the increase in flow was greater in the normal subjects (284±88%) than in the diabetics with SND (187±80%,
P
=0.084) and without SND (177±72%,
P
=0.028). However, the increase in flow in response to cold was lower in the diabetics with SND (14±10%) than in those without SND (31±12%) (
P
=0.015) and the normal subjects (48±24%) (
P
<0.001). The flow response to cold was related to the myocardial uptake of [
11
C]HED (
P
<0.001). Flow-mediated brachial artery dilation was impaired in the diabetics compared with the normal subjects, but it was similar in the diabetics with and without SND.

Conclusions
—Diabetic autonomic neuropathy is associated with an impaired vasodilator response of coronary resistance vessels to increased sympathetic stimulation, which is related to the degree of SND.
Chlamydia pneumoniae
Infection and Early Asymptomatic Carotid Atherosclerosis
Authors: Markus Hugh S. , Sitzer Matthias , Carrington David , Mendall Michael A , Steinmetz Helmuth
Published: June 2012

Background
—Chronic
Chlamydia pneumoniae
infection has been implicated in the pathogenesis of atherosclerosis but whether it plays a role at an early stage in the disease is uncertain. An early estimate of atherosclerosis can be obtained by ultrasonic imaging of the carotid artery to determine intima-media thickness (IMT) and the thickness of any atheroma plaques.

Methods and Results
—In 983 normal population individuals aged 30 to 70 years, we measured common carotid artery (CCA) and carotid bulb IMT, and also carotid plaque thickness and the degree of internal carotid artery (ICA) stenosis.
C. pneumoniae
IgA titers of ≥16 and IgG titers of ≥64 were taken as positive. There was no association between
C. pneumoniae
IgA or IgG seropositivity with right, left, or mean CCA or bulb IMT, or with the presence of carotid plaques. There was a significant association between IgA seropositivity and >50% mean carotid stenosis with an odds ratio of 5.24 (95% CI 1.24 to 22.21,
P
=0.0245) after controlling for age and sex; after controlling for other cardiovascular risk factors, this was not significant 3.96 (95% CI 0.84 to 18.78,
P
=0.082). No association was found between IgA or IgG seropositivity and markers of fibrinogen, log C-reactive protein, or leukocyte count.

Conclusions
—We found no evidence that serological evidence of
C. pneumoniae
infection is associated with early atherosclerosis. It is possible that IgA seropositivity is associated with more advanced disease but this hypothesis needs to be examined in a population with a higher prevalence of advanced atherosclerosis. We found no evidence that
C. pneumoniae
results in a chronic systemic inflammatory state.
Aggregating Human Platelets Stimulate Expression of Vascular Endothelial Growth Factor in Cultured Vascular Smooth Muscle Cells Through a Synergistic Effect of Transforming Growth Factor-β
1
and Platelet-Derived Growth Factor
AB
Authors: Kronemann Nicola , Bouloumié Anne , Bassus Steffen , Kirchmaier Carl M. , Busse Rudi , Schini-Kerth Valérie B.
Published: June 2012

Background
—Vascular endothelial growth factor (VEGF), an endothelial mitogen and chemoattractant, has been implicated in the recovery of the endothelium after balloon injury. The increased expression of VEGF in vascular smooth muscle cells (SMC) at sites of injury suggests that this cell type may be a major cellular source of VEGF. This study examined whether aggregating platelets stimulate VEGF expression in cultured SMC.

Methods and Results
—VEGF expression in SMC was assessed by Northern blot analysis and by reverse transcription followed by polymerase chain reaction and the release of VEGF by Western blot analysis and immunoassay. Platelet-derived products (PDP) released by aggregating human platelets time-dependently and concentration-dependently enhanced VEGF mRNA levels, mainly that coding for the soluble splice variant VEGF
165/164
, and stimulated the release of VEGF protein. These effects were potentiated by transient acidification of PDP, which release bioactive transforming growth factor (TGF)-β
1
, and mimicked by platelet-derived growth factor (PDGF)
AB
and TGF-β
1
in a synergistic manner. Both a TGF-β–neutralizing antibody and a PDGF-neutralizing antibody significantly attenuated the effect of acidified PDP on VEGF production.

Conclusions
—Aggregating human platelets induce VEGF mRNA expression in cultured SMC and the subsequent release of VEGF protein. This effect can be attributed to a supra-additive action of PDGF
AB
and TGF-β
1
and may represent a novel mechanism by which platelets contribute to the recovery of the endothelial lining at sites of balloon-injured arteries.
Process of Progression of Coronary Artery Lesions From Mild or Moderate Stenosis to Moderate or Severe Stenosis
Authors: Yokoya Koichi , Takatsu Hisato , Suzuki Takahiko , Hosokawa Hiroaki , Ojio Shinsuke , Matsubara Tetsuo , Tanaka Tsutomu , Watanabe Sachiro , Morita Norihiko , Nishigaki Kazuhiko , Takemura Genzou , Noda Toshiyuki , Minatoguchi Shinya , Fujiwara Hisayoshi
Published: June 2012

Background
—The process of progression in coronary artery disease is unknown.

Methods and Results
—The subjects were 36 patients with 36 objective vessels with clinically significant progression of coronary artery disease (≥15% per year) in whom 4 serial coronary arteriograms (CAGs) were performed at intervals of ≈4 months in a 1-year period. The degree of progression of percent stenosis between each of 2 serial CAGs was classified as marked (M: ≥15%), slight (S: 5% to 14%), and no progression (N: <5%). From the pattern of progression, the 36 vessels were classified as 14 type 1 vessels with marked progression (N→N→M in 13 vessels and S→S→M in 1 vessel) and 22 type 2 vessels without marked progression (S→S→S in 18 vessels, N→S→S in 4). Percent stenosis at the first, second, third, and final CAGs was 44±14%, 46±13%, 46±13%, and 88±10% (
P
<0.05 versus first CAG) in type 1 vessels and 44±11%, 50±9%, 59±9%, and 67±9% in type 2 vessels (
P
<0.05 for second, third, and final CAGs versus first CAG). Type 1 vessels featured the sudden appearance of severe stenosis due to marked progression, angina pectoris, or myocardial infarction (71%) and Ambrose type II eccentric lesions indicating plaque rupture or thrombi (57%). Type 2 vessels featured continuous slight progression of stenosis with smooth vessel walls; angina pectoris (14%) occurred when the percent stenosis reached a severe level. An increase in serum C-reactive protein was observed only in the type 2 vessel group, which suggests a relation between continuous slight progression and inflammatory change.

Conclusions
—Two types of stenosis progression provide a new insight into the mechanism of coronary artery disease.
Moderate Alcohol Consumption and the Risk of Sudden Cardiac Death Among US Male Physicians
Authors: Albert Christine M. , Manson JoAnn E. , Cook Nancy R. , Ajani Umed A. , Gaziano J. Michael , Hennekens Charles H.
Published: June 2012

Background
—Individuals who consume high amounts of alcohol (>5 drinks/d) have increased risks of ventricular arrhythmia and sudden cardiac death (SCD). However, the relationship is less clear for drinkers of light-to-moderate amounts.

Methods and Results
—We prospectively assessed whether light-to-moderate alcohol drinkers have a decreased risk of SCD among 21 537 male participants in the Physicians Health Study who were free of self-reported cardiovascular disease and provided complete information on alcohol intake at study entry. Over 12 years of follow-up, 141 SCDs were confirmed. After control for multiple confounders, men who consumed 2 to 4 drinks/wk (RR=0.40; 95% CI, 0.22 to 0.75;
P
=0.004) or 5 to 6 drinks/wk (RR=0.21; 95% CI, 0.08 to 0.56;
P
=0.002) at baseline had significantly reduced risks of SCD compared with those who rarely or never consumed alcohol. The relationship for SCD was U-shaped (
P
=0.002), with the risk approaching unity at ≥2 drinks/d. In contrast, the relationship of alcohol intake and nonsudden CHD death was L-shaped or linear (
P
for trend=0.02).

Conclusions
—In these prospective data, men who consumed light-to-moderate amounts of alcohol (2 to 6 drinks/wk) had a significantly reduced risk of SCD compared with those who rarely or never consumed alcohol.
Gene Expression of Antioxidative Enzymes in the Human Heart
Authors: Dieterich Sabine , Bieligk Ursula , Beulich Kathrin , Hasenfuss Gerd , Prestle Juergen
Published: June 2012

Background
—An increase in oxidative stress is suggested to be intimately involved in the pathogenesis of heart failure. However, gene expression of enzymes that metabolize reactive oxygen metabolites has not been investigated in the human heart.

Methods and Results
—Myocardial tissue homogenates of the left ventricular wall from hearts in end-stage failure due to dilated (DCM) or ischemic (ICM) cardiomyopathy (n=12 each), as well as from nonfailing donor hearts (n=12), were analyzed for mRNA levels of manganese superoxide dismutase (MnSOD), copper-zinc superoxide dismutase (CuZnSOD), glutathione peroxidase (GPX), and catalase by Northern blot analyses. Protein levels of MnSOD, CuZnSOD, and catalase were determined by Western blot or ELISA. MnSOD, CuZnSOD, and GPX mRNA levels were similar in all 3 groups. In contrast, catalase mRNA levels were found to be increased by 123±23% in DCM hearts and by 93±10% in ICM hearts (
P
<0.01 each) compared with control hearts. Likewise, catalase protein levels were found to be increased in failing hearts (DCM by 90±10%, ICM by 90±13%;
P
<0.05 each) compared with control hearts. In addition, the observed upregulation of catalase mRNA and protein in failing hearts was attended by an increased catalase enzyme activity (DCM by 124±16%, ICM by 117±15%;
P
<0.01 each), whereas MnSOD, CuZnSOD, and GPX enzyme activity levels were unchanged in failing compared with nonfailing myocardium.

Conclusions
—Increased oxidative stress in human end-stage heart failure may result in a specific upregulation of catalase gene expression as a compensatory mechanism, whereas SOD and GPX gene expression remain unaffected.
Ambulatory Ventricular Arrhythmias in Patients With Heart Failure Do Not Specifically Predict an Increased Risk of Sudden Death
Authors: Teerlink John R. , Jalaluddin Muhammad , Anderson Susan , Kukin Marrick L. , Eichhorn Eric J. , Francis Gary , Packer Milton , Massie Barry M.
Published: June 2012

Background
—Ventricular arrhythmias are a frequent finding in congestive heart failure (CHF) patients and a cause of concern for physicians caring for them. Previous studies have reached conflicting conclusions regarding the importance of ventricular arrhythmias as predictors of sudden death in patients with CHF. This study examined the independent predictive value of ventricular arrhythmias for sudden death and all-cause mortality in PROMISE (Prospective Randomized Milrinone Survival Evaluation).

Methods and Results
—Ventricular arrhythmias were analyzed and quantified by use of prespecified criteria on baseline ambulatory ECGs from 1080 patients with New York Heart Association (NYHA) class III/IV symptoms and a left ventricular ejection fraction ≤35% enrolled in PROMISE. The relationship of ventricular arrhythmias and other clinical parameters to overall mortality and sudden death classified by an independent, blinded mortality committee was determined. There were 290 deaths, of which 139 were classified as sudden. Of the several measures of ventricular ectopy that were univariate predictors, the frequency of nonsustained ventricular tachycardia (NSVT) was the most powerful predictor and remained a significant independent predictor when included with other clinical variables in multivariate models of both sudden death mortality and non–sudden death mortality. However, multiple logistic analysis with models including the clinical variables with and without the NSVT variable demonstrated that the frequency of NSVT did not add significant information beyond the clinical variables.

Conclusions
—This study demonstrates that ventricular arrhythmias do not specifically predict sudden death in patients with moderate-to-severe heart failure. Thus, the finding of asymptomatic NSVT on ambulatory ECG does not identify specific candidates for antiarrhythmic or device therapy.
Major Racial Differences in Coronary Constrictor Response Between Japanese and Caucasians With Recent Myocardial Infarction
Authors: Pristipino Christian , Beltrame John F. , Finocchiaro Maria L. , Hattori Ryuichi , Fujita Masatoshi , Mongiardo Rocco , Cianflone Domenico , Sanna Tommaso , Sasayama Shigetake , Maseri Attilio
Published: June 2012

Background
—Enhanced coronary vasomotion may contribute to acute coronary occlusion during the acute phase of myocardial infarction (AMI). Japanese have a higher incidence of variant angina than Caucasian patients, but racial differences in vasomotor reactivity early after AMI are controversial.

Methods and Results
—The same team studied 15 Japanese and 19 Caucasian patients within 14 days of AMI by acetylcholine injection into non–infarct-related (NIRA) and infarct-related (IRA) coronary arteries followed by nitroglycerin. Incidence of vasodilation, vasoconstriction, spasm, and basal tone were assessed in proximal, middle, and distal segments after each drug bolus by quantitative angiography. Japanese patients had much lower cholesterol levels than Caucasians (183±59 versus 247±53 mg/dL,
P
<0.006) but showed a lower incidence of vasodilation (2% versus 9% of coronary segments) and a greater incidence of spasm after acetylcholine (47% versus 15% of arteries,
P
<0.00001). Incidence of spasm was higher in IRAs than in NIRAs in both populations (67% versus 39% and 23% versus 11%, respectively). Multivessel spasm was more common (64% versus 17%,
P
<0.02) and vasoconstriction of nonspastic segments was greater in Japanese patients (−23.4±14.9% versus −20.1±15.7%,
P
<0.02) in the presence of similar average basal coronary tone with respect to post–nitroglycerin dilation and of nonsignificant differences of coronary atherosclerotic score.

Conclusions
—Soon after AMI, Japanese patients exhibited a 3-fold-greater incidence of spasm and greater vasoconstriction of nonspastic segments after acetylcholine than Caucasians. The causes of such differences warrant further investigation because they may have relevant pathophysiological and therapeutic implications.