α-Glucosidase inhibitor miglitol attenuates glucose fluctuation, heart rate variability and sympathetic activity in patients with type 2 diabetes and acute coronary syndrome: a multicenter randomized controlled (MACS) study.

BACKGROUND: Little is known about clinical associations between glucose fluctuations including hypoglycemia, heart rate variability (HRV), and the activity of the sympathetic nervous system (SNS) in patients with acute phase of acute coronary syndrome (ACS). This pilot study aimed to evaluate the short-term effects of glucose fluctuations on HRV and SNS activity in type 2 diabetes mellitus (T2DM) patients with recent ACS. We also examined the effect of suppressing glucose fluctuations with miglitol on these variables. METHODS: This prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group comparative study included 39 T2DM patients with recent ACS, who were randomly assigned to either a miglitol group (n = 19) or a control group (n = 20). After initial 24-h Holter electrocardiogram (ECG) (Day 1), miglitol was commenced and another 24-h Holter ECG (Day 2) was recorded. In addition, continuous glucose monitoring (CGM) was performed throughout the Holter ECG. RESULTS: Although frequent episodes of subclinical hypoglycemia (≤4.44 mmo/L) during CGM were observed on Day 1 in the both groups (35% of patients in the control group and 31% in the miglitol group), glucose fluctuations were decreased and the minimum glucose level was increased with substantial reduction in the episodes of subclinical hypoglycemia to 7.7% in the miglitol group on Day 2. Holter ECG showed that the mean and maximum heart rate and mean LF/HF were increased on Day 2 in the control group, and these increases were attenuated by miglitol. When divided 24-h time periods into day-time (0700-1800 h), night-time (1800-0000 h), and bed-time (0000-0700 h), we found increased SNS activity during day-time, increased maximum heart rate during night-time, and glucose fluctuations during bed-time, which were attenuated by miglitol treatment. CONCLUSIONS: In T2DM patients with recent ACS, glucose fluctuations with subclinical hypoglycemia were associated with alterations of HRV and SNS activity, which were mitigated by miglitol, suggesting that these pathological relationships may be a residual therapeutic target in such patients. Trial registration Unique Trial Number, UMIN000005874 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000006929 ).

Effects of the Addition of Eicosapentaenoic Acid to Strong Statin Therapy on Inflammatory Cytokines and Coronary Plaque Components Assessed by Integrated Backscatter Intravascular Ultrasound.

BACKGROUND: The effects of eicosapentaenoic acid (EPA) on coronary artery disease have been previously reported; however, those of the addition of EPA to strong statins on coronary plaque components and local inflammatory cytokines are not known. METHODS AND RESULTS: A total of 95 patients who had been treated with strong statin for at least 6 months were randomized into 2 groups: an EPA group (additional treatment with EPA at 1,800 mg/day, n=48) or a control group (no additional treatment, n=47), for 6 months. The tissue characteristics of target coronary plaque in each patient were analyzed using IB-IVUS before and after treatment. We also measured plasma levels of inflammatory cytokines sampled in the coronary sinus (CS) and peripheral vein.A significant reduction in lipid volume (18.5 ± 1.3 to 15.0 ± 1.5 mm(3), P=0.007) and a significant increase in fibrous volume (22.9 ± 0.8 to 25.6 ± 1.1 mm(3), P=0.01) were observed in IB-IVUS image analyses in the EPA group, but no significant changes in the plaque components in the control group. CS levels of pentraxin 3 and monocyte chemoattractant protein-1 were lower after than before treatment with EPA (3.3 ± 2.1 to 2.6 ± 1.2 ng/ml, 120.4 ± 26.2 to 110.2 ± 26.8 pg/ml, P=0.015 and P=0.008, respectively); however, there were no significant changes in those inflammatory cytokines between pre- and post-treatment in the control group. CONCLUSIONS: The addition of EPA was associated with reduced lipid volume in coronary plaques and decreased inflammatory cytokines.

Plasma microRNA-100 is associated with coronary plaque vulnerability.

BACKGROUND: Although numerous studies have reported altered plasma levels of various microRNAs (miRNAs) in patients with cardiovascular disease, there are no data on the relationship between plasma miRNAs and vulnerable coronary plaque. In this study, we investigated whether plasma miRNAs might be a sensitive marker of coronary plaque vulnerability. METHODS AND RESULTS: Integrated backscatter intravascular ultrasound (IB-IVUS) was performed in 32 consecutive patients with angina pectoris who underwent percutaneous coronary intervention. Three-dimensional analysis of IB-IVUS was performed to determine the percentage of lipid volume (%LV) and fibrous volume (%FV). Circulating miRNAs were measured in EDTA-plasma simultaneously obtained from the aorta and the coronary sinus (CS). Muscle-enriched (miR-133a, miR-208a, miR-499), vascular-enriched (miR-92a, miR-100, miR-126, miR-127, miR-145), and myeloid cell-enriched miRNAs (miR-155, miR-223) were measured. Plasma miR-100 was higher in the CS than in the aorta, but there were no significant differences in the levels of other miRNAs between the aorta and CS. Plasma miR-100 in the aorta was positively correlated with %LV (r=0.48, P<0.01) and negatively correlated with %FV (r=-0.41, P<0.05). Importantly, transcoronary concentration gradient of circulating miR-100 was more strongly correlated with %LV (r=0.53, P<0.01) and %FV (r=-0.56, P<0.01). CONCLUSIONS: miR-100 might be released into the coronary circulation from vulnerable coronary plaques. This study provides insights into the role of miRNAs in coronary atherosclerotic disease.

Impact of Indoxyl Sulfate, a Uremic Toxin, on Non-Culprit Coronary Plaque Composition Assessed on Integrated Backscatter Intravascular Ultrasound.

BACKGROUND: Uremic toxin has emerged as an important determinant of cardiovascular risk. The aim of this study was to examine the relationship between serum uremic toxin and coronary plaque composition on integrated backscatter intravascular ultrasound (IB-IVUS). METHODS AND RESULTS: IB-IVUS was performed in 47 patients with planned treatment for angina pectoris. Non-culprit intermediate plaque analyzed in this study had to be >5 mm apart from the intervention site. 3-D IB-IVUS analysis was performed to determine percent lipid volume (LV) and fibrous volume (FV). We also measured serum uremic toxins (indoxyl sulfate [IS], asymmetric dimethylarginine [ADMA], and p-cresol [PC]). Glomerular filtration rate correlated with IS (r=-0.329, P=0.04), but did not correlate with ADMA or PC. Percent LV correlated with IS (r=0.365, P=0.02), but did not correlate with ADMA or PC. Percent FV also correlated with IS (r=-0.356, P=0.03), but did not correlate with ADMA or PC. On multivariate regression, only IS was associated with percent LV (r=0.359, P=0.04) and percent FV (r=-0.305, P=0.04) independently of potentially confounding coronary risk factors. CONCLUSIONS: Among the uremic toxins, serum IS might be a novel useful biomarker to detect and monitor lipid-rich coronary plaque on IB imaging.

Elevated Concentration of Interferon-Inducible Protein of 10 kD (IP-10) Is Associated With Coronary Atherosclerosis.

Several studies have shown that various chemokines are more highly expressed in atherosclerotic plaques than in normal vessel walls. In the present study, we investigated the relationship between coronary atherosclerosis and noteworthy chemokines, including interferon-inducible protein of 10 kD (IP-10); monocyte chemoattractant protein 1 (MCP-1); regulated on activation, normal T-cell expressed and secreted (RANTES); and high-sensitivity C-reactive protein (hsCRP), an established marker of atherosclerotic disease. We studied 28 patients who underwent coronary angiography because of suspected coronary artery disease (CAD). CAD was defined as stenosis of more than 50% of the vessel diameter on coronary angiograms. Blood samples were obtained both from the aorta and the coronary sinus (CS) just before coronary angiography. Relative to CAD (-) patients, those who were CAD (+) tended to have higher plasma concentrations of IP-10 in the aorta, as well as significantly higher transcoronary concentration gradients of circulating IP-10. There were no significant differences between the two groups in aortic plasma concentrations or transcoronary concentration gradients of MCP-1, RANTES, and hsCRP. Furthermore, both the aortic plasma concentrations and transcoronary concentration gradients of IP-10 correlated with the Gensini score (r = 0.58 and r = 0.63, respectively, P < 0.01), while the plasma MCP-1, RANTES, and serum hsCRP concentrations did not. This study suggests that IP-10 is a good surrogate marker of coronary atherosclerosis.

Effects of telmisartan on inflammatory cytokines and coronary plaque component as assessed on integrated backscatter intravascular ultrasound in hypertensive patients.

BACKGROUND: Telmisartan has unique pleiotropic effects in addition to renin-angiotensin system (RAS)-inhibition effects. The aim of this study was to evaluate the effects of telmisartan on the coronary plaque component and local inflammatory cytokines. METHODS AND RESULTS: A total of 50 patients with hypertension were randomized to 2 groups: the telmisartan group (additional treatment with telmisartan 80mg/day, n=25) or the control group (additional treatment with other anti-hypertensive drugs except RAS blockers, n=25) for 6 months. Tissue characteristics of target coronary plaque were analyzed using integrated backscatter intravascular ultrasound (IB-IVUS) before and after treatment. Plasma levels of inflammatory cytokines sampled in the coronary sinus (CS) and peripheral vein were also measured. Significant increases in fibrous volume (51.2±10.4 to 58.3±7.7%, P=0.03) and reductions in lipid volume (38.4±12.4 to 32.8±9.7%, P=0.03) were observed on IB in the telmisartan group, while there were no significant changes in the plaque component in the control group. CS levels of inflammatory cytokines (matrix metalloproteinase [MMP]3, tumor necrosis factor-α, high-sensitivity C-reactive protein and MMP9) were lower after than before treatment in the only telmisartan group (7.7±6.1 to 5.5±4.9ng/ml, 3.1±1.9 to 2.3±2.0pg/ml, 5.6±6.0 to 2.2±2.4mg/L, 36.1±39.3 to 19.9±27.5ng/ml, P=0.02, P=0.03, P=0.04, P=0.07, respectively). CONCLUSIONS: Decreased local inflammatory response and plaque stabilization on IB imaging were observed after 6 months of telmisartan treatment. These findings might be associated with local anti-inflammatory and anti-arteriosclerotic effects of telmisartan.

Cardiac rehabilitation reduces serum levels of oxidized low-density lipoprotein.

BACKGROUND: Oxidized low-density lipoprotein (oxLDL) levels have been found to play an important role in the progression of atherosclerosis. However, methods for effectively reducing oxLDL levels have not been established. Comprehensive cardiac rehabilitation (CR) with exercise training prevents the progression of atherosclerosis, and might reduce oxLDL levels. METHODS AND RESULTS: We measured the serum levels of malondialdehyde-modified LDL (MDA-LDL), a marker of oxLDL, in 136 patients who were enrolled in a 6-month CR program. Peak oxygen consumption (V̇O2) and MDA-LDL levels were analyzed, before and 6 months after enrolment. In total, 67 patients completed the CR program (CR group) and 69 patients failed to complete the program (non-CR group). Peak V̇O2increased significantly in the CR group (P<0.01). The levels of MDA-LDL decreased significantly in the CR group (P<0.01) but not in the non-CR group. ∆V̇O2(peak V̇O2after CR-peak V̇O2before CR) was negatively associated with ∆MDA-LDL (MDA-LDL after CR-MDA-LDL before CR) (R(2)=0.11, P=0.01). Multiple regression analysis showed that continuing CR was an independent determining factor for lowering MDA-LDL levels. CONCLUSIONS: CR decreases oxLDL levels in patients with cardiovascular diseases. Moreover, CR may prevent cardiovascular events through an antioxidative effect.

Pentraxin 3 is a local inflammatory marker in atrial fibrillation.

Increasing evidence indicates that inflammation contributes to the pathogenesis of atrial fibrillation (AF). Pentraxin 3 (PTX3) is produced abundantly in local inflammatory lesions while C-reactive protein (CRP) is produced mainly in the liver. In this study, we investigated whether a local level of PTX3 might be a sensitive marker for the local inflammation of AF. Blood from the periphery and left atrial appendage (LAA) was sampled from 23 patients with AF undergoing pulmonary vein isolation, and from 10 control subjects with Wolff-Parkinson-White syndrome. We measured peripheral and LAA plasma concentrations of CRP, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and PTX3. Plasma PTX3 concentrations in both locations were higher in patients with AF than in control subjects. PTX3 concentrations were significantly higher in the LAA than the periphery in patients with AF (3.7 ± 1.4 vs 3.3 ± 1.2 ng/ml, P < 0.01), but not in control subjects (2.4 ± 0.5 vs 2.4 ± 0.5 ng/ml, not significant). Patients and controls showed no significant differences in CRP, IL-6, or TNF-α concentrations between the periphery and LAA. Interestingly, there was a significant positive correlation between LAA plasma concentrations of PTX3 and left atrial volume (r = 0.55, P < 0.01). These data demonstrate that local PTX3 production in the left atrium might reflect the local inflammation of AF.

Congenital long QT syndrome with compound mutations in the KCNH2 gene.

Congenital long QT syndrome is a genetic disorder encompassing a family of mutations that can lead to aberrant ventricular electrical activity. We report on two brothers with long QT syndrome caused by compound mutations in the KCNH2 gene inherited from parents who had no prolonged QT interval on electrocardiography. The proband had syncope, and his elder brother suffered from ventricular fibrillation. Genetic testing revealed that both brothers had multiple mutations in the KCNH2 gene, including a missense mutation of C1474T (exon 6) as well as a frameshift/nonsense mutation, resulting from the insertion of 25 nucleotides, which caused an altered amino acid sequence beginning at codon 302 and a premature termination codon (i.e., TAG) at codon 339 (exon 4). Family genetic screening found that their father had the same frameshift mutation, and their mother and sister had the same missense mutation, in the KCNH2 gene. However, these other family members were asymptomatic, with normal QT intervals on electrocardiography. These results suggest that compound mutations in the KCNH2 gene inherited independently from the parents made the phenotypes of their sons more severe.

Massive tricuspid regurgitation due to pacemaker-lead puncture of the tricuspid valve: successful diagnosis by 3-dimensional echocardiography.

An 83-year-old woman presented to our echocardiographic center with symptoms of right heart failure. A dual-chamber DDDR pacemaker had been implanted 9 years earlier. Two-dimensional echocardiography revealed right atrial and ventricular enlargement and massive tricuspid regurgitation with immobilization of the anterior leaflet of the tricuspid valve. Three-dimensional transesophageal echocardiography showed that the pacemaker lead had punctured the leaflet. These echocardiographic findings were confirmed during surgery. The pacemaker lead was transected and removed, and pericardial patch closure of the leaflet hole and tricuspid annuloplasty were performed. The mechanism of regurgitation was elucidated by real-time three-dimensional echocardiography, and surgical repair was straightforward.

Ghrelin protects the heart against ischemia-induced arrhythmias by preserving connexin-43 protein.

Vagal nerve stimulation has been postulated to confer an antifibrillatory effect. We studied whether ghrelin administration would exert an antiarrhythmic effect via modulation of autonomic nerve activity in rats after acute myocardial ischemia (MI). Male Sprague-Dawley rats were exposed to 30 min of ischemia following ligation of the left coronary artery. Animals were then randomized to receive either ghrelin (n = 26) or saline (n = 26) during the period of coronary ligation. Power spectral analysis of heart-rate variability revealed that the administration of ghrelin increased the high-frequency (HF) power and decreased the low-frequency (LF)/HF ratio. Ventricular tachyarrhythmias were less frequent in rats after MI who received ghrelin in comparison with rats that received saline. Immunoblotting and immunohistochemistry revealed that rats given saline alone during MI exhibited a marked reduction in phosphorylated connexin-43 within the left ventricle, whereas those that received ghrelin displayed only minor reductions in comparison with sham-operated rats. These effects of ghrelin were diminished by the coadministration of atropine or the blockade of vagal afferents. These data demonstrate that the beneficial effect of ghrelin might be mediated by modulation of cardiac autonomic nerve activity.

Eosinophilic myocarditis due to Churg-Strauss syndrome with markedly elevated eosinophil cationic protein.

A 67-year-old woman with asthma visited our hospital with increasing dyspnea and new-onset paresthesia and purpura in her legs. Physical examination showed a wheeze, pretibial edema, and surrounding purpura. Chest X-rays showed cardiac decompensation and an electrocardiogram revealed a new ST-T change. Laboratory data showed leukocytosis, hypereosinophilia (10,450/µL), troponin T(+), elevated BNP, and markedly elevated eosinophil cationic protein (ECP) (> 150 ng/mL). Echocardiography revealed diffuse left ventricular hypokinesis (ejection fraction 30%) with increased wall thickness. Coronary angiography was normal. Cardiac magnetic resonance imaging implied diffuse myocardial edema and subendocardial late gadolinium enhancement. Skin biopsy of purpura showed superfi cial perivascular dermatitis with remarkable eosinophilic infiltrations. No evidence of drug allergies, parasitic infection, or myeloproliferative disorder was detected. Based on these findings, a diagnosis of eosinophilic myocarditis due to Churg-Strauss syndrome was considered. She was administered prednisolone at a dose of 1 mg/kg, cyclophosphamide, and diuretics. Several markers of eosinophilic myocarditis and heart failure gradually improved, including ECP. She was discharged 30 days later with no cardiac event. Eosinophilic myocarditis is characterized by predominantly eosinophilic infi ltration. Eosinophilic granule proteins, such as ECP and major basic protein, play important roles in the pathogenesis of eosinophilic myocarditis. We experienced a rare case of eosinophilic myocarditis due to Churg-Strauss syndrome. Markedly elevated ECP played an important role in the early diagnosis and subsequent reduction in ECP served as a marker of monitoring. In an asthmatic patient with dyspnea, hypereosinophilia, and vasculitis, Churg-Strauss syndrome with eosinophilic myocarditis should be considered.

Pharmacology of Aldosterone and the Effects of Mineralocorticoid Receptor Blockade on Cardiovascular Systems.

UNLABELLED: It is well-known that aldosterone plays an important role in reabsorption of sodium and fluid, and in potassium excretion in kidneys via epithelial mineralocorticoid receptor (MR) activation. Recent studies have shown that aldosterone causes cardiovascular remodeling not only in a blood pressure-dependent manner, but also in a blood pressure-independent manner by decreasing nitric oxide bioavailability and modulating oxidative stress, leading to vascular inflammation. In addition, MR blockade does provide beneficial effects associated with cardiovascular protection, resulting in a reduction of cardiovascular morbidity and mortality. A growing body of evidence suggests that MR blockade is a promising therapeutic target to help prevent cardiovascular events. KEY WORDS: Aldosterone; Mineralocorticoid receptor; Nitrix oxide; Renin-angiotensin-aldosterone system.

Gender disparities in the association between epicardial adipose tissue volume and coronary atherosclerosis: a 3-dimensional cardiac computed tomography imaging study in Japanese subjects.

BACKGROUND: Growing evidence suggests that epicardial adipose tissue (EAT) may contribute to the development of coronary artery disease (CAD). In this study, we explored gender disparities in EAT volume (EATV) and its impact on coronary atherosclerosis. METHODS: The study population consisted of 90 consecutive subjects (age: 63 ± 12 years; men: 47, women: 43) who underwent 256-slice multi-detector computed tomography (MDCT) coronary angiography. EATV was measured as the sum of cross-sectional epicardial fat area on CT images, from the lower surface of the left pulmonary artery origin to the apex. Subjects were segregated into the CAD group (coronary luminal narrowing > 50%) and non-CAD group. RESULTS: EATV/body surface area (BSA) was higher among men in the CAD group than in the non-CAD group (62 ± 13 vs. 33 ± 10 cm3/m2, p < 0.0001), but did not differ significantly among women in the 2 groups (49 ± 18 vs. 42 ± 9 cm3/m2, not significant). Multivariate logistic analysis showed that EATV/BSA was the single predictor for >50% coronary luminal narrowing in men (p < 0.0001). Predictors excluded were age, body mass index, hypertension, diabetes mellitus, and hyperlipidemia. CONCLUSIONS: Increased EATV is strongly associated with coronary atherosclerosis in men.

Validation of longitudinal peak systolic strain by speckle tracking echocardiography with visual assessment and myocardial perfusion SPECT in patients with regional asynergy.

BACKGROUND: Automated function imaging (AFI) is a recently developed method of calculating the longitudinal peak systolic strains (LS) of the regional left ventricular (LV) wall using speckle tracking echocardiography and displaying them on a single bull's-eye map. The feasibility of AFI in patients with regional LV wall motion abnormalities caused by myocardial infarction (MI) was evaluated by comparison with visual assessment and myocardial perfusion single-photon emission computed tomography (SPECT). METHODS AND RESULTS: Segmental LS was measured by AFI in 60 patients with MI (67 ± 11 years) and 58 controls (71 ± 9 years). Wall thickening (WT) was measured by SPECT in 20 patients with MI. There was a strong positive linear relationship between the wall motion score index by expert visual assessment and global LS. The receiver-operating characteristic analysis revealed the best cutoff value of 11% < LS to identify hypokinetic segments. The overall accuracy of wall motion scoring by LS in the 2,006 segments was 96.8% (κ = 0.90) compared with visual assessment. The correlation coefficient between LS and WT was R² = 0.65 in the 340 segments. CONCLUSIONS: Assessment of LV regional asynergy by AFI showed good agreement with visual and SPECT assessments. AFI is clinically useful for quantitative assessment of LV regional wall motion abnormalities.

Platypnea-orthodeoxia syndrome associated with patent foramen ovale and aortic ectasia.

A 59-year-old man was admitted for dyspnea on exertion and edema. The patient did not have any pulmonary diseases that could cause dyspnea. Transesophageal echocardiography on the tilting bed with contrast infusion revealed a right-to-left shunt through the patent foramen ovale. Therefore, he was diagosed as platypnea-orthodeoxia syndrome due to the patent foramen ovale. Surgical closure was done and all of his symptoms had improved.

Effect of ghrelin on autonomic activity in healthy volunteers.

Ghrelin is a novel growth hormone (GH)-releasing peptide originally isolated from the stomach. Recently, we have shown that ghrelin suppresses cardiac sympathetic activity and prevents early left ventricular remodeling in rats with myocardial infarction. In the present study, we evaluated the effect of ghrelin on autonomic nerve activity in healthy human subjects. An intravenous bolus of human synthetic ghrelin (10µg/kg) was administered to 10 healthy men (mean age, 33 years). Holter monitoring assessment was performed before and during 2h after the ghrelin therapy. The standard deviation of normal RR intervals (SDNN), square root of the mean of the sum of the squares of differences between adjacent RR intervals (rMSSD), high-frequency power (HF), and low-frequency power (LF) were analyzed. Blood samples were also obtained before and after the therapy. A single administration of ghrelin decreased both heart rate and blood pressure. Interestingly, ghrelin significantly decreased the LF and LF/HF ratio of heart rate variability and increased the SDNN, rMSSD, and HF. Ghrelin also elicited a marked increase in circulating GH, but not insulin-like growth factor-1. These data suggest that ghrelin might suppress cardiac sympathetic nerve activity and stimulate cardiac parasympathetic nerve activity.

Acute pulmonary thromboembolism from deep vein thrombosis induced by trauma to the popliteal vein with a tennis racket.

Acute pulmonary thromboembolism (PTE) is mainly caused by deep vein thrombosis (DVT) and sometimes leads to a fatal outcome. Few cases of sport-related lower extremity DVT, involving direct external trauma, have been reported. A 58-year-old man, without any risk factors for thromboembolism suffered acute PTE from DVT after playing tennis. A detailed history revealed that he had hit his popliteal vein with each swing of his tennis racket and the site of the trauma, at popliteal fossa, was exactly the same as the site of the DVT formation. Therefore, the cause of DVT was suspected to be the repeated trauma to the popliteal vein. The repeated external trauma to the popliteal vein may have caused vascular endothelial damage, leading to DVT. .