Takayuki Ohwada

Granulocyte-Macrophage Colony–Stimulating Factor Prevents the Progression of Atherosclerosis via Changes in the Cellular and Extracellular Composition of Atherosclerotic Lesions in Watanabe Heritable Hyperlipidemic Rabbits

BACKGROUND A cytokine network is involved in atherogenesis. This study was conducted to investigate the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the development and composition of atherosclerotic lesions in Watanabe heritable hyperlipidemic (WHHL) rabbits. METHODS AND RESULTS GM-CSF (10 microg. kg-1. d-1) was administered to 4-month-old WHHL rabbits (n=9) 5 days a week for 7.5 months, whereas an equal dose of human serum albumin was administered to controls (n=9). The cholesterol levels were not changed significantly by the treatment. Age-matched 4-month-old rabbits (n=7) had atheromatous plaques over 30.7+/-5.7% of the inner surface area of the aortic arch. After treatment, the percentages of surface atheromatous plaques to total aortic arch area were 45.0+/-12.6% in the GM-CSF group and 74.3+/-11.0% in controls (P<0.0001). Histological examination demonstrated that GM-CSF reduced the ratio of intima to media (P<0.01) and cross-sectional areas of atherosclerotic lesions (P<0.0001). Quantitative analysis indicated a marked decrease in the areas of smooth muscle cells (P=0.0001), collagen (P=0.0001), and extracellular lipid deposits (P<0.05) of atheromatous plaques in GM-CSF-treated rabbits compared with controls. The terminal deoxynucleotidyltransferase-mediated dUTP-digoxigenin nick end-labeling (TUNEL) method and immunohistochemistry were performed to examine the relationship between decreased atherosclerotic lesions and apoptosis. The percentage of TUNEL-positive cells increased in the GM-CSF group (GM-CSF, 24.1+/-4.4% versus control, 11.6+/-3.2%; P<0.0001). GM-CSF enhanced the apoptosis of smooth muscle cells in the shoulder region and the fibrous cap (P<0.0001), suggesting one of the mechanisms for the antiatherogenic effect. CONCLUSIONS GM-CSF altered the composition of atherosclerotic lesions and reduced the atherosclerosis in WHHL rabbits.

Acute heart failure volume control multicenter randomized (AVCMA) trial: comparison of tolvaptan and carperitide.

Acute decompensated heart failure (ADHF) is a common and highly morbid cardiovascular disorder. Diuresis is a major therapy for the reduction of congestive symptoms. However, most diuretics cause hyponatremia, which is a worsening factor of ADHF patients prognosis. The purpose of this study was to examine the efficacy and safety of tolvaptan, which is a selective vasopressin V2 receptor antagonist and produces water excretion without changes in sodium excretion, compared with carperitide.

Morphological and functional changes in coronary vessel evoked by repeated endothelial injury in pigs

OBJECTIVE We examined the morphological changes induced by repeated endothelial denudation in coronary artery (CA), as well as functional changes in the endothelium-dependent and smooth muscle responses to various vasoactive agents during the process of intimal thickening. METHODS We observed vascular responses in denuded and non-denuded portions of pig CA while being fed a normal diet (n = 11, N group) or 2% cholesterol diet (n = 25, C group) to intracoronary acetylcholine (ACh), 5-hydroxytryptamine (5-HT), substance P (SP), and isosorbide dinitrate (ISDN) with and without the nitric oxide synthesis inhibitor N omega-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg i.v.) over a period of 8 weeks. Balloon endothelial denudation of the left anterior descending CA was carried out every 2 weeks. RESULTS In N group, maximum vasoconstriction was obtained with ACh 2 weeks after the first denudation [26 +/- 5% vs. 1 +/- 1% pre-denudation, p < 0.05]. L-NAME did not affect ACh-induced CA diameter changes. Thereafter, the response to ACh was attenuated by repeated denudation in N groups. However, the degree of 5-HT-induced CA narrowing at the denuded portion increased from 7 +/- 4% (0 week) to 88 +/- 8% (8 weeks) (p < 0.05). The changes resulted in severe myocardial ischaemia, and suggested that endothelium-dependent vasodilation was progressively attenuated while hyperreactivity of vascular smooth muscle simultaneously increased. Vasodilation induced by SP was attenuated somewhat, but ISDN-induced vasodilation was preserved. Although mild hypercholesterolaemia was induced in C group, the vascular responses to these vasoactive agents did not differ from those of N group. CONCLUSIONS Repeated CA endothelial injury and regeneration induce the change of morphology and vascular reactivity in the denuded portion regardless of atherogenic diet. This study strongly suggests that intimal thickening caused by repeated endothelial injury and regeneration induces specific vascular responses to vasoactive agents. Moreover, it is also suggested that during the progression of intimal thickening, increased vascular smooth muscle contraction and decreased endothelium-dependent dilation appear in a stimulus-dependent manner, often leading to severe coronary vasoconstriction accompanied with definitive ECG ST change.

Vasopressin V2 receptor antagonist tolvaptan is effective in heart failure patients with reduced left ventricular systolic function and low blood pressure.

Diuresis is a major therapy for the reduction of congestive symptoms in acute decompensated heart failure (ADHF) patients. Carperitide has natriuretic and vasodilatory effects, and tolvaptan produces water excretion without electrolyte excretion. We previously reported the usefulness of tolvaptan compared to carperitide in ADHF patients with fluid volume retention. The purpose of this study was to examine whether the efficacy of tolvaptan was altered in ADHF patients with reduced left ventricular systolic function and in those with hypotension. A total of 109 hospitalized ADHF patients were randomly assigned to either a tolvaptan or a carperitide treatment group. Baseline clinical characteristics were not different between the two groups. We divided these patients based on the left ventricular ejection fraction (EF) by echocardiography, and blood pressure (BP) at the time of admission. Daily urine volume between the tolvaptan and carperitide groups in patients with preserved EF (≥ 50%) was not different, however, in those with reduced EF (< 50%), the urine volume was significantly higher in the tolvaptan group than in the carperitide group (day 2, 3, 4, P < 0.05 for all). Daily urine volume did not differ between these two groups in the high blood pressure group (BP ≥ 140 mmHg), but was significantly higher in the tolvaptan group than in the carperitide group (day 1, P = 0.021; day 3, P = 0.017) in the low blood pressure group (BP < 140 mmHg). The present study reveals that tolvaptan is more effective than carperitide, especially in ADHF patients with reduced left ventricular systolic function and without hypertension.

Long-Term Effects and Prognosis in Acute Heart Failure Treated with Tolvaptan: The AVCMA Trial

Background. Diuresis is a major therapy for the reduction of congestive symptoms in acute decompensated heart failure (ADHF) patients. We previously reported the efficacy and safety of tolvaptan compared to carperitide in hospitalized patients with ADHF. There were some reports of cardio- and renal-protective effects in carperitide; therefore, the purpose of this study was to compare the long-term effects of tolvaptan and carperitide on cardiorenal function and prognosis. Methods and Results. One hundred and five ADHF patients treated with either tolvaptan or carperitide were followed after hospital discharge. Levels of plasma B-type natriuretic peptide, serum sodium, potassium, creatinine, and estimated glomerular filtration rate were measured before administration of tolvaptan or carperitide at baseline, the time of discharge, and one year after discharge. These data between tolvaptan and carperitide groups were not different one year after discharge. Kaplan-Meier survival curves demonstrated that the event-free rate regarding all events, cardiac events, all cause deaths, and rehospitalization due to worsening heart failure was not significantly different between tolvaptan and carperitide groups. Conclusions. We demonstrated that tolvaptan had similar effects on cardiac and renal function and led to a similar prognosis in the long term, compared to carperitide.

Vascular composition data supporting the role of N-3 polyunsaturated fatty acids in the prevention of cardiovascular disease events.

N-3 polyunsaturated fatty acids (PUFAs) are thought to have protective effects against cardiovascular disease. Here, we report the relationship between serum PUFA concentrations and plaque composition, as evaluated by virtual histology-intravascular ultrasound (VH-IVUS). Consecutive patients (n=61) who underwent percutaneous coronary intervention (PCI) were pre-operatively examined using VH-IVUS to assess the composition of culprit plaques. Gray-scale IVUS and VH-IVUS data of fibrous, fibro-fatty, necrotic core, and dense calcium regions of plaques were estimated at the minimal luminal area sites of culprit lesions. Serum levels of high-sensitivity C-reactive protein (hsCRP) and PUFAs, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA), were compared between patients with (ACS, n=27) and without acute coronary syndrome (non-ACS, n=34) before PCI. Multiple logistic regression analysis of the data showed that EPA/AA under the median was more highly associated with ACS than hsCRP over the median. In addition, EPA/AA was negatively correlated with the percentage of fibrous plaque regions and EPA/AA and DHA/AA were positively correlated with the percentage of dense calcium regions in plaques. Furthermore, the correlation index of EPA/AA was the most highly (R=0.513) correlated with the percentage of dense calcium regions in plaques.

Importance of multi-detector computed tomography for percutaneous coronary intervention in a patient with type V dual left anterior descending artery

A 58-year-old woman came to our hospital because of chest pain. Multi-detector computed tomography (MDCT) showed type V dual left anterior descending artery (LAD) and a 90% stenosis in segment 1 of the right coronary artery. Two days after examination, she was admitted to our hospital because of recurrent chest pain. She was diagnosed with acute myocardial infarction. Coronary angiography showed a 99% stenosis in segment 1 and a dual LAD. She received successful percutaneous coronary intervention (PCI) to segment 1 with a bare metal stent. Type V dual LAD is a rare and complicated coronary anomaly with the short LAD originating from the left sinus of valsalva and the long LAD originating from the right sinus of valsalva. Identifying anatomy of the coronary artery is important when making a strategy for PCI. In types IV-VI dual LAD, the anatomic features can be misinterpreted at coronary angiography. MDCT was useful in understanding the anomaly of dual LAD and performing PCI in the present case.

STENTING STRATEGY AND FOLLOW-UP RESULTS OF MULTI-CENTER REGISTRY IN FUKUSHIMA CITY FOR LEFT MAIN CORONARY ARTERY DISEASE: BARE METAL STENT VERSUS DRUG-ELUTING STENT

An appropriate treatment strategy for left main trunk (LMT) lesions is still controversial in the drug-eluting stent (DES) era. Consecutive LMT stenting cases (n = 155) between January 2008 and January 2013 in 4 hospitals in Fukushima city were retrospectively analyzed. We excluded the patients suffering from cardiogenic shock before the stenting procedure. Among those cases, 60 patients had acute coronary syndrome, and remaining 95 had stable angina pectoris. Out of 155 cases, 45 patients were treated with bare metal stents (BMSs) and 110 patients were treated with DESs. All cases were succeeded in the initial procedure. Mean stent size of BMS was 3.85 ± 0.34 mm while that of DES was 3.46 ± 0.17 mm (P<0.001). At the follow up coronary angiography (255-day on average), % stenosis of BMS group was 26.6 ± 15.0% and that of DES group was 20.4 ± 12.6% (P = 0.006). The mean observation period for clinical events was 738.8 ± 480.3 days. Major adverse cardiac events-free rates for each group were compared and no significant differences were evident between the 2 groups (11.1% vs. 19.1%, ns). The present study demonstrated that use of BMSs would be a viable option in the treatment of LMT lesions when it is possible to use a large-sized stent (>3.5 mm).