Optimal Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Patients With Multivessel Disease and Diabetes.

There is a scarcity of data on clinical outcomes after intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients with multivessel disease and diabetes. The Optimal Intravascular Ultrasound Guided Complex Percutaneous Coronary Intervention study multivessel cohort was a prospective, multicenter, single-arm trial enrolling 1,021 patients who underwent multivessel PCI, including left anterior descending coronary artery using IVUS, aiming to meet the prespecified OPTIVUS criteria for optimal stent expansion. We compared the clinical outcomes between those patients with and without diabetes. The primary end point was a composite of death, myocardial infarction, stroke, or any coronary revascularization. There were 560 patients (54.8%) with diabetes and 461 patients (45.2%) without diabetes. The mean age was not different between the 2 groups (70.9 ± 9.7 vs 71.7 ± 10.4 years, p = 0.17). Patients with diabetes more often had chronic kidney disease and complex coronary artery disease, as indicated by the greater total number of stents and longer total stent length. The rate of meeting the OPTIVUS criteria was not different between the 2 groups (61.2% vs 60.7%, p = 0.83). The cumulative 1-year incidence of the primary end point was not different between the 2 groups (10.8% vs 9.8%, log-rank p = 0.65). After adjusting for confounders, the risk of diabetes relative to nondiabetes remained insignificant for the primary end point (hazard ratio 0.97, 95% confidence interval 0.65 to 1.44, p = 0.88). In conclusion, in patients who underwent multivessel IVUS-guided PCI and were managed with contemporary clinical practice, patients with diabetes had similar 1-year outcomes to patients without diabetes.

Left sinus of Valsalva aneurysm causing acute myocardial infarction with compression of the left main coronary trunk.

Sinus of Valsalva aneurysm (SVA) is a rare cardiac anomaly that commonly originates from the right or noncoronary sinuses and rarely from the left sinus. SVA is usually diagnosed in the setting of clinical sequelae of a rupture. We herein report a case of an unruptured left SVA presenting as acute myocardial infarction. A 54-year-old woman with a history of radical operation for patent ductus arteriosus in childhood was transferred to our hospital. An electrocardiogram indicated extensive myocardial ischemia with ST elevation. Urgent coronary angiography was performed but was unable to identify the left coronary artery. Subsequent aortography and computed tomography revealed a large SVA originating from the left sinus and compressing the left coronary artery. The patient died after approximately one month of intensive care, including mechanical circulatory support and coronary artery bypass grafting. Autopsy confirmed that the left main coronary trunk was stretched and compressed by the SVA and revealed unexpected atherosclerosis in the left anterior descending artery. Although a left SVA is an extremely rare anomaly, it occasionally provokes fatal myocardial infarction. Since an SVA might hinder performing percutaneous coronary intervention, cardiac surgery should be considered when myocardial ischemia is recognized. Learning objective: We herein report a case of an unruptured left sinus of Valsalva aneurysm (SVA) with acute myocardial infarction. Urgent percutaneous coronary intervention (PCI) was unsuccessful, as the left coronary artery was compressed by the SVA. The patient died after intensive care, including coronary artery bypass grafting (CABG). SVA, especially from the left sinus, is extremely rare but occasionally provokes myocardial infarction by compressing the coronary arteries. Because SVA might hinder PCI, CABG should be considered when myocardial ischemia is recognized.

Severe mitral regurgitation in chronic adult T-cell leukemia/lymphoma with granulomatous valvular inflammation.

Adult T-cell leukemia/lymphoma (ATLL) is a mature peripheral T-cell neoplasm caused by human T-cell leukemia virus type I (HTLV-1) infection. Besides the oncogenic property, HTLV-1 causes HTLV-1-associated myelopathy/tropical spastic paraparesis and certain inflammatory diseases via a complex host immune response to latent virus infection. Cardiac involvement of ATLL is rare, with the majority of cases being disclosed in postmortem autopsy in patients with advanced subtypes. We herein report the case of a 64-year-old female patient with indolent chronic ATLL with severe mitral regurgitation. Although the condition of ATLL was stable, dyspnea on exertion gradually progressed over the course of three years and echocardiography revealed marked thickening of the mitral valve. Finally, the patient experienced hemodynamic collapse with atrial fibrillation and underwent surgical valve replacement. The removed mitral valve was grossly edematous and swollen. A histological examination revealed a granulomatous reaction mimicking the active phase of rheumatic valvulitis, with the infiltration of ATLL cells that were immunohistochemically positive for CD3, CD4, FoxP3, HLA-DRα, and CCR4. The postoperative course was uneventful, with the exception that Sjögren's syndrome was noted. The history of rheumatic fever was unclear, and such unique valvular pathology was presumably related to autoimmune mechanisms associated with HTLV-1 infection. Learning objective: We report a case of chronic adult T-cell leukemia/lymphoma (ATLL) with isolated valvular infiltration with a unique histology of granulomatous reaction. Human T-cell leukemia virus type I infection may accelerate autoimmune reactions and cardiac inflammation, irrespective of indolent clinical subtype. Among ATLL cases, possible progression of valvular insufficiency and heart failure in patients with cardiac symptoms should be carefully evaluated.

Limb-Based Patency After Surgical vs Endovascular Revascularization in Patients with Chronic Limb-Threatening Ischemia.

PURPOSE: To determine whether limb-based patency (LBP) after infrainguinal revascularization for chronic limb-threatening ischemia (CLTI) is similar between bypass surgery and endovascular therapy (EVT). MATERIALS AND METHODS: The database for the Surgical Reconstruction vs Peripheral Intervention in Patients With Critical Limb Ischemia (SPINACH) study was interrogated to identify 130 patients (mean age 73±8 years; 94 men) who underwent bypass surgery and 271 patients (mean age 74±10 years; 178 men) who underwent EVT alone. Skin perfusion pressure (SPP) and the ankle-brachial index (ABI) were measured before the procedure and at 0, 1, and 3 months after revascularization. The outcome measure was hemodynamically evaluated LBP (SPP ≥10 mm Hg or ABI ≥0.1) maintained over the first 3 months after treatment. Any reintervention or major amputation was regarded as loss of LBP. The associations between the revascularization strategy (bypass vs EVT) and between the preoperative characteristics and the study outcome (ie, SPP- or ABI-based LBP), were determined using generalized linear mixed models with a logit link function. Patency rates are presented with the 95% confidence interval (CI). RESULTS: The bypass surgery group had a higher stage of limb severity (WIfI) and anatomic complexity (GLASS) than the EVT group, whereas the EVT group had a higher prevalence of heart failure. Both SPP- and ABI-based LBP rates were higher in the bypass group than in the EVT group. SPP-based LBP rates at 3 months were 73.8% (95% CI 63.4% to 84.2%) in the bypass group and 46.2% (95% CI 38.5% to 53.8%) in the EVT group; the corresponding ABI-based LBP rates were 71.5% (95% CI 61.8% to 81.2%) and 44.0% (95% CI 37.3% to 50.7%). CONCLUSION: LBP is an important concept in the new global vascular guidelines for assessing the anatomic and hemodynamic status of CLTI patients. The present study found that LBP was significantly lower in the EVT group vs the bypass surgery group.

Effect of 1-Month Dual Antiplatelet Therapy Followed by Clopidogrel vs 12-Month Dual Antiplatelet Therapy on Cardiovascular and Bleeding Events in Patients Receiving PCI: The STOPDAPT-2 Randomized Clinical Trial.

Importance: Very short mandatory dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with a drug-eluting stent may be an attractive option. Objective: To test the hypothesis of noninferiority of 1 month of DAPT compared with standard 12 months of DAPT for a composite end point of cardiovascular and bleeding events. Design, Setting, and Participants: Multicenter, open-label, randomized clinical trial enrolling 3045 patients who underwent PCI at 90 hospitals in Japan from December 2015 through December 2017. Final 1-year clinical follow-up was completed in January 2019. Interventions: Patients were randomized either to 1 month of DAPT followed by clopidogrel monotherapy (n=1523) or to 12 months of DAPT with aspirin and clopidogrel (n=1522). Main Outcomes and Measures: The primary end point was a composite of cardiovascular death, myocardial infarction (MI), ischemic or hemorrhagic stroke, definite stent thrombosis, or major or minor bleeding at 12 months, with a relative noninferiority margin of 50%. The major secondary cardiovascular end point was a composite of cardiovascular death, MI, ischemic or hemorrhagic stroke, or definite stent thrombosis and the major secondary bleeding end point was major or minor bleeding. Results: Among 3045 patients randomized, 36 withdrew consent; of 3009 remaining, 2974 (99%) completed the trial. One-month DAPT was both noninferior and superior to 12-month DAPT for the primary end point, occurring in 2.36% with 1-month DAPT and 3.70% with 12-month DAPT (absolute difference, -1.34% [95% CI, -2.57% to -0.11%]; hazard ratio [HR], 0.64 [95% CI, 0.42-0.98]), meeting criteria for noninferiority (P < .001) and for superiority (P = .04). The major secondary cardiovascular end point occurred in 1.96% with 1-month DAPT and 2.51% with 12-month DAPT (absolute difference, -0.55% [95% CI, -1.62% to 0.52%]; HR, 0.79 [95% CI, 0.49-1.29]), meeting criteria for noninferiority (P = .005) but not for superiority (P = .34). The major secondary bleeding end point occurred in 0.41% with 1-month DAPT and 1.54% with 12-month DAPT (absolute difference, -1.13% [95% CI, -1.84% to -0.42%]; HR, 0.26 [95% CI, 0.11-0.64]; P = .004 for superiority). Conclusions and Relevance: Among patients undergoing PCI, 1 month of DAPT followed by clopidogrel monotherapy, compared with 12 months of DAPT with aspirin and clopidogrel, resulted in a significantly lower rate of a composite of cardiovascular and bleeding events, meeting criteria for both noninferiority and superiority. These findings suggest that a shorter duration of DAPT may provide benefit, although given study limitations, additional research is needed in other populations. Trial Registration: ClinicalTrials.gov Identifier: NCT02619760.

Utility of 99 mTc-Pyrophosphate Scintigraphy in Diagnosing Transthyretin Cardiac Amyloidosis in Real-World Practice.

Background: Amyloid transthyretin (ATTR) cardiac amyloidosis has now been recognized as one of the major causes of heart failure, especially in elderly patients. The purpose of the present study was to validate the usefulness of technetium-99 m (99 mTc)-pyrophosphate (99 mTc-PYP) scintigraphy in the screening diagnosis for ATTR amyloidosis in daily clinical practice. Methods and Results: Ninety-eight patients underwent 99 mTc-PYP scintigraphy in the previous 3 years (PYP positive/negative, 18/80), of whom 29 underwent concomitant endomyocardial biopsy (ATTR positive/negative, 9/20). The sensitivity and specificity of 99 mTc-PYP scintigraphy for the diagnosis of biopsy-proven ATTR amyloidosis were 0.889 and 0.950, respectively. Age, gender, N-terminal prohormone of brain natriuretic peptide (NT-proBNP) level, or electrocardiogram findings did not differ significantly between PYP-positive and PYP-negative patients. Left ventricular (LV) wall thickness was significantly greater in PYP-positive than in PYP-negative patients, but LV ejection fraction or prevalence of atrial fibrillation was similar between groups. In the PYP-positive patients, higher uptake of PYP correlated with younger age and lower NT-proBNP. Conclusions: 99 mTc-PYP scintigraphy was useful, with high sensitivity and specificity in the screening diagnosis for ATTR cardiac amyloidosis, which is difficult to diagnose on clinical characteristics alone. 99 mTc-PYP scintigraphy should be considered to elucidate the underlying causes of heart failure, especially in elderly patients based on the higher prevalence of ATTR cardiac amyloidosis in this population.

CORRIGENDUM: Utility of 99 mTc-Pyrophosphate Scintigraphy in Diagnosing Transthyretin Cardiac Amyloidosis in Real-World Practice.

[This corrects the article DOI: 10.1253/circrep.CR-19-0015.].

Initial and 3-year results after subintimal versus intraluminal approach for long femoropopliteal occlusion treated with a self-expandable nitinol stent.

BACKGROUND: Intraluminal femoropopliteal stenting enables favorable dilation and good immediate results; however, whether this contributes to long-term patency is unclear. We compared patency after femoropopliteal stenting for a long occlusion using either an intraluminal or subintimal approach. METHODS: Between January 2004 and December 2011, 902 endovascular procedures using either an intraluminal approach (651 procedures) or a subintimal approach (251 procedures) for long femoropopliteal occlusion were analyzed retrospectively. The outcomes of this study were periprocedural complication; primary, assisted-primary, and secondary patency; and overall survival. RESULTS: The mean follow-up period of survivors was 29 ± 16 months. Between the intraluminal and subintimal approach, technical success (91% vs 90%; P = .71) and periprocedural complications (11% vs 13%; P = .34) were similar. However, procedure time was significantly longer for the intraluminal approach (126 ± 63 minutes vs 98 ± 49 minutes; P = .003). The improvement of ankle-brachial index was also similar. A quarter of cases started with the intraluminal approach were switched to a subintimal approach. There was no significant difference in primary, assisted-primary and secondary patency at 3 years between the two groups (55% vs 53%; P = .30; 65% vs 74%; P = .11; and 80% vs 85%; P = .37). The 3-year overall survival also did not differ significantly between groups (84% vs 86%; P = .55). After adjusting for baseline differences, the subintimal approach was found to be similar to the intraluminal approach for primary patency (hazard ratio, 1.21; 95% confidence interval, 0.94-1.56; adjusted P = .14). CONCLUSIONS: Initial result and 3-year patency was similar in both approaches. Given the longer procedure time and high crossover rate, we suggest that a subintimal approach may be preferred in the treatment of long femoropopliteal occlusions with stenting.

Endovascular treatment for infrainguinal vessels in patients with critical limb ischemia: OLIVE registry, a prospective, multicenter study in Japan with 12-month follow-up.

BACKGROUND: Recent technical advances have made endovascular treatment (EVT) an alternative first-line treatment for critical limb ischemia. METHODS AND RESULTS: A prospective multicenter study was conducted to evaluate the clinical outcomes of 314 Japanese critical limb ischemia patients (mean age, 73±10 years) with infrainguinal arterial lesions who underwent EVT. Patients were enrolled from December 2009 to July 2011 and were followed-up for 12 months. The primary end point was amputation-free survival (AFS) at 12 months. Secondary end points were anatomic, clinical, and hemodynamic measures, including 12-month freedom from major adverse limb events. The 12-month AFS rate was 74%, with body mass index <18.5 (hazard ratio [HR], 2.22; P=0.008), heart failure (HR, 1.73; P=0.04), and wound infection (HR, 1.89; P=0.03) associated with a poor prognosis for AFS. The 12-month major adverse limb event-free rate was 88%, with hemodialysis (HR, 1.98; P=0.005), heart failure (HR, 1.69; P=0.02), and Rutherford classification 6 (HR, 2.25; P=0.002) associated with a poor prognosis for major adverse limb events. The median time for wound healing was 97 days, with body mass index <18.5 (HR, 0.54; P=0.03) and wound infection (HR, 0.60; P=0.04) being significant risk factors for unhealed wounds after EVT. At 12 months, 34% had undergone reintervention (bypass surgery, 2.6%; repeat EVT, 31.7%), and 73% were major adverse event-free. CONCLUSIONS: The high reintervention rate notwithstanding, EVT was an effective treatment for Japanese critical limb ischemia patients with infrainguinal disease, with satisfactory AFS and major adverse limb event-free rates. The results of this study will be helpful for the future evaluation of critical limb ischemia therapy. CLINICAL TRIAL REGISTRATION: URL: http://www.umin.ac.jp/ctr. Unique identifier: UMIN000002830.

Increased productivity of tumor necrosis factor-alpha in helper T cells in patients with systolic heart failure.

BACKGROUND AND AIMS: Whereas increased circulating proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), play an important role in heart failure, where and how TNF-alpha production is upregulated remains largely unknown. We studied the productivity of TNF-alpha in peripheral lymphocytes and underlying mechanisms in patients with heart failure. METHODS: Symptomatic NYHA II-IV patients with chronic heart failure with systolic dysfunction (n=39, aged 74+/-11, ejection fraction [EF]<==50%) were compared with asymptomatic NYHA I patients (n=18, aged 72+/-10, EF>50%) and normal subjects (n=15, aged 67+/-11). Lymphocyte subsets (CD3, CD4, and CD8) and intracellular production of TNF-alpha in peripheral leukocytes were quantified by immunofluorescent flow cytometry, and relationships between these parameters and circulating proinflammatory cytokines were analyzed. RESULTS: Subpopulation of TNF-alpha-producing CD4 was larger in NYHA II-IV patients (23.7% [18.0-28.6]) than in normal subjects (17.1% [6.5-19.5], p<0.05) and was correlated with plasma TNF-alpha levels (r=0.26, p<0.05), EF (r=-0.26, p<0.05), CD4/CD8 ratios (r=0.42, p<0.001), and subpopulation of TNF-alpha-producing monocytes (r=0.47, p<0.0001). Plasma levels of soluble CD14 and interleukin-12 (IL-12) were significantly higher in NYHA II-IV patients than in normal subjects (1971 ng/mL [1740-2375] vs. 1607 ng/mL [1530-1930], p<0.01; and 121 pg/mL [62-230] vs. 62 pg/mL [54-99], p<0.05, respectively), and plasma IL-12 levels were correlated with plasma TNF-alpha levels (r=0.41, p<0.001). CONCLUSIONS: Increased productivity of TNF-alpha in helper T cells, associated with their dominance over cytotoxic T cells, may partially contribute to an increase in circulating TNF-alpha levels in heart failure.

Local delivery of soluble TNF-alpha receptor 1 gene reduces infarct size following ischemia/reperfusion injury in rats.

Apoptosis in the myocardium is linked to ischemia/reperfusion injury, and TNF-alpha induces apoptosis in cardiomyocytes. A significant amount of TNF-alpha is detected after ischemia and reperfusion. Soluble TNF-alpha receptor 1 (sTNFR1) is an extracellular domain of TNF-alpha receptor 1 and is an antagonist to TNF-alpha. In the present study, we examined the effects of sTNFR1 on infarct size in acute myocardial infarction (AMI) following ischemia/reperfusion. Male Wistar rats were subjected to left coronary artery (LCA) ligation. After 30 min of LCA occlusion, the temporary ligature on the LCA was released and blood flow was restored. Immediately after reperfusion, a total of 200 microg of sTNFR1 or LacZ plasmid was injected into three different sites of the left ventricular wall. At 6 h, 1 and 2 days after reperfusion, the TNF-alpha bioactivity in the myocardium was significantly higher in rats receiving LacZ plasmid than in sham-operated rats, whereas sTNFR1 plasmid significantly suppressed the increase in the TNF-alpha bioactivity. The sTNFR1 plasmid significantly reduced DNA fragmentation and caspase activity compared to the LacZ plasmid. Finally, the sTNFR1 expression-plasmid treatment significantly reduced the area of myocardial infarction at 2 days after ischemia/reperfusion compared to LacZ plasmid. In conclusion, the TNF-alpha bioactivity in the heart increased from the early stage of ischemia/reperfusion, and this increase was thought to contribute in part to the increased area of myocardial infarction. Suppression of TNF-alpha bioactivity with the sTNFR1 plasmid reduced the infarct size in AMI following ischemia and reperfusion.

Anti-monocyte chemoattractant protein-1 gene therapy attenuates left ventricular remodeling and failure after experimental myocardial infarction.

BACKGROUND: Increased expression of monocyte chemoattractant protein-1 (MCP-1) has recently been described in clinical and experimental failing heart. However, its pathophysiological significance in heart failure remains obscure. We thus determined whether MCP-1 is increased in post-myocardial infarction (MI) hearts and its blockade can attenuate the development of left ventricular (LV) remodeling and failure. METHODS AND RESULTS: Anterior MI was produced in mice by ligating the left coronary artery. After 4 weeks, MI mice exerted LV dilatation and contractile dysfunction in association with myocyte hypertrophy and interstitial fibrosis of noninfarcted LV. MCP-1 mRNA levels were increased by 40-fold in noninfarcted LV 1 day after ligation, which persisted until 28 days. To block the MCP-1 signals, an N-terminal deletion mutant of the human MCP-1 gene was transfected into the limb skeletal muscle 3 days before and 14 days after ligation. This method improved the survival rate of mice with MI at 4 weeks (61% versus 87%, P<0.05) as well as attenuated LV cavity dilatation and contractile dysfunction, interstitial fibrosis, recruitment of macrophages, and myocardial gene expression of tumor necrosis factor-alpha and transforming growth factor-beta compared with the nontreated MI mice despite the comparable infarct size calculated as percent LV circumference. CONCLUSIONS: The activation of MCP-1 expression contributes to the LV remodeling and failure after MI. An anti-MCP-1 gene therapy can be a useful novel strategy for preventing post-MI heart failure.

Beneficial effects of angiotensin-converting enzyme inhibition on sarcoplasmic reticulum function in the failing heart of the Dahl rat.

Inhibition of angiotensin-converting enzyme (ACE) retards the process of myocardial remodeling and contractile dysfunction that leads to heart failure. However, the intracellular mechanisms by which ACE inhibition preserves myocardial contractility are largely unclear. Using a model of heart failure induced by hypertension in Dahl salt-sensitive (DS) rats, the mechanisms by which ACE inhibitors (ACEI) exert a beneficial effect on myocardial contractility were studied. Dahl salt-resistant (DR) rats, DS rats not given temocapril (DS/T-), and DS rats treated with temocapril (10 mg/kg per day from 10 to 17 weeks of age, DS/T+) were fed an 8% NaCl diet from 8 to 17 weeks of age (n=8, each group). Echocardiography, hemodynamic measurement, histology, contraction of isolated skinned papillary muscle, and Western blot analysis were carried out. At an elevated final blood pressure similar to that of the DS/T- rats, DS/T+ rats exhibited (1) a decrease in left ventricular (LV) mass associated with decreases in both cardiomyocyte size and interstitial fibrosis; (2) improvement of both systolic and diastolic LV function; and (3) an increase in caffeine contraction after constant Ca(2+)-loading with 8-bromo-cAMP into the sarcoplasmic reticulum (SR) associated with an increase in Ser16-phosphorylated phospholamban, as compared with the DS/T- rats. In addition to inhibition of myocardial remodeling, a restoration of the Ca(2+)-handling ability of the SR by normalized phosphorylated phospholamban may contribute to the improved LV contractile function achieved by chronic treatment with an ACEI.

Oxidative stress mediates tumor necrosis factor-alpha-induced mitochondrial DNA damage and dysfunction in cardiac myocytes.

BACKGROUND: Tumor necrosis factor-alpha (TNF-alpha) and angiotensin II (Ang II) are implicated in the development and further progression of heart failure, which might be, at least in part, mediated by the production of reactive oxygen species (ROS). However, the cause and consequences of this agonist-mediated ROS production in cardiac myocytes have not been well defined. Recently, we demonstrated that increased ROS production was associated with mitochondrial DNA (mtDNA) damage and dysfunction in failing hearts. We thus investigated whether the direct exposure of cardiac myocytes to TNF-alpha and Ang II in vitro could induce mtDNA damage via production of ROS. METHODS AND RESULTS: TNF-alpha increased ROS production within cultured neonatal rat ventricular myocytes after 1 hour, as assessed by 2',7'-dichlorofluorescin diacetate fluorescence microscopy. TNF-alpha also decreased mtDNA copy number by Southern blot analysis in association with complex III activity, which was prevented in the presence of the antioxidant alpha-tocopherol. A direct exposure of myocytes to H2O2 caused a similar decrease in mtDNA copy number. In contrast, Ang II did not affect mtDNA copy number, despite the similar increase in ROS production. TNF-alpha-mediated ROS production and a decrease in mtDNA copy number were inhibited by the sphingomyelinase inhibitor D609. Furthermore, N-acetylsphingosine (C2-ceramide), a synthetic cell-permeable ceramide analogue, increased myocyte ROS production, suggesting that TNF-alpha-mediated ROS production and subsequent mtDNA damage were mediated by the sphingomyelin-ceramide signaling pathway. CONCLUSIONS: The intimate link between TNF-alpha, ROS, and mtDNA damage might play an important role in myocardial remodeling and failure.

Pioglitazone, a peroxisome proliferator-activated receptor-gamma agonist, attenuates left ventricular remodeling and failure after experimental myocardial infarction.

BACKGROUND: Peroxisome proliferator-activated receptor-gamma activators have recently been implicated as regulators of cellular proliferation and inflammatory response such as cytokine expression. Because proinflammatory cytokines play a critical role in left ventricular (LV) remodeling after myocardial infarction (MI), we examined the effects of pioglitazone treatment in an experimental model of chronic heart failure. METHODS AND RESULTS: Mice with extensive anterior MI were treated with placebo or pioglitazone (3 mg x kg(-1) x d(-1)) as a dietary supplement for 4 weeks starting 6 hours after surgery. Infarct size and glucose levels were similar among all groups. LV cavity dilatation and dysfunction by echocardiography were significantly attenuated in MI mice given pioglitazone. LV end-diastolic pressure was increased in MI mice and was significantly reduced by pioglitazone treatment. Pioglitazone partially normalized LV dP/dt(max) and dP/dt(min), indices of LV contractile function, which were significantly reduced in MI mice. Improvement of LV function by pioglitazone was accompanied by a decrease in myocyte hypertrophy and interstitial fibrosis and a reduced expression of tumor necrosis factor-alpha, transforming growth factor-beta, and monocyte chemoattractant protein-1 genes in the noninfarcted LV from MI mice. LV inducible nitric oxide synthase and gelatinase B protein levels were increased in MI and were not altered by pioglitazone treatment. CONCLUSIONS: Pioglitazone improved LV remodeling and function in mice with post-MI heart failure. This effect was associated with an attenuated LV expression of inflammatory cytokines and chemokines. Peroxisome proliferator-activated receptor-gamma ligands have promise as preventive and therapeutic agents against heart failure.

Greater oxidative stress in healthy young men compared with premenopausal women.

Coronary risk factors, including age, hypertension, diabetes mellitus, hyperlipidemia, and smoking, are associated with enhanced oxidative stress, which is implicated as a potential mechanism for atherogenesis and atherosclerotic cardiovascular diseases. Male sex is one of the well-known cardiovascular risk factors. We tested the hypothesis that oxidative stress is greater in men than in women. Plasma thiobarbituric acid-reactive substances (TBARS) and urinary 8-isoprostaglandin F2alpha (8-iso-PGF2alpha) were measured in 52 young men and 51 age-matched women. The subjects were healthy, were not smokers, and were not taking any medications or vitamins. Age, blood pressure, plasma cholesterol, and glucose did not differ between the groups. Baseline TBARS (2.32 +/- 0.11 [men] versus 1.87 +/- 0.09 [women] nmol/mL, P<0.01) and 8-iso-PGF2alpha (292 +/- 56 [men] versus 164 +/- 25 [women] pg/mg creatinine, P<0.05) were higher in men than in women. Supplementation of antioxidant vitamins for 4 weeks in men produced a significant reduction in TBARS and 8-iso-PGF2alpha by 34% (P<0.01) and 48% (P<0.05), respectively. Plasma superoxide dismutase, catalase, and vitamin E levels were comparable between the groups. Enhanced oxidative stress in men may provide a biochemical link between male sex and atherosclerotic diseases related to oxidative stress.

Post-beta-receptor impairment in the regulation of myofibrillar Ca2+ sensitivity in tachypacing-induced canine failing heart.

Although one of the salient abnormalities in signal transduction of failing myocardium is downregulation of the beta-adrenergic receptor, the extent of presentation of downstream pathways distal to beta-receptors is misunderstood. We addressed this question in tachypacing-induced canine failing heart by assessing changes in myofibrillar Ca2+ sensitivity and troponin I phosphorylation. At a basal state, no significant difference in myofibrillar Ca2+ sensitivity was found between normal and failing hearts. Isoproterenol 8-bromo-cylic adenosine monophosphate (cAMP), and 8-bromo-cAMP isobutylmethylxantine all significantly decreased the Ca2+ sensitivity in the normal, but not in the failing, heart. EMD57033 (10 microM ), a myofibrillar Ca2+ sensitizer increased the Ca2+ sensitivity to a similar extent in both groups. The troponin I phosphorylation levels were significantly decreased in the failing heart. These results suggest that abnormalities of the beta-adrenergic signaling system exist not only at the receptor level but also at downstream steps after cAMP production.