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Makoto Sahara

Publications and source records attributed to Makoto Sahara.

12 recordsLinked to original sources
PubMed2006

Three-vessel coronary artery disease complicated with congestive heart failure in a highly aged patient with tetralogy of Fallot having undergone palliative surgeries.

An increasing number of patients with tetralogy of Fallot (TOF) are reaching older age. We encountered a 75-year-old woman with uncorrected TOF and concomitant severe coronary artery disease (CAD) with congestive heart failure. Her CAD risk factor was hyperlipidemia, which had been untreated. Successful percutaneous coronary interventions have improved her clinical condition and provided long-term survival. Although CAD is considered to be a rare complication in adults with TOF, both strict modification of CAD risk factors and early detection of CAD would be also required in this population, given the residual TOF lesions relating to acute exacerbation of clinical presentation.

Aged↗
PubMed2006

New insights in the treatment strategy for pulmonary arterial hypertension.

INTRODUCTION: Recent advances in our understanding of the pathophysiological and molecular mechanisms involved in pulmonary arterial hypertension have led to the development of novel and rational pharmacological therapies. In addition to conventional therapy (i.e., supplemental oxygen and calcium channel blockers), prostacyclin or endothelin receptor antagonists have been recommended as a first-line therapy for pulmonary arterial hypertension. However, these treatments have potential limitations with regard to their long-term efficacy and improvement in survival. Furthermore, intravenous prostacyclin (epoprostenol) therapy, which is recommended by most experts for patients with New York Heart Association (NYHA) functional class IV, is complicated, uncomfortable for patients, and expensive because of the cumbersome administration system. Considering these circumstances, it is necessary to develop additional novel therapeutic approaches that target the various components of this multifactorial disease. CASE REPORT: In this short review, we present an overview of the current treatment options for pulmonary arterial hypertension and describe a case report with primary pulmonary hypertension. A male patient with NYHA functional class IV and showing no response to calcium channel blockers and prostacyclin exhibited significantly improved exercise tolerance and hemodynamics and long-term survival for more than 2.5 years after receiving an oral combination therapy of a phosphodiesterase type 5 inhibitor (sildenafil), phosphodiesterase type 3 inhibitor (pimobendan), and nicorandil. FUTURE PERSPECTIVE: We also discuss the background and plausible potential mechanisms involved in this case, as well as future perspectives in the treatment of pulmonary arterial hypertension.

Anticoagulants↗
PubMed2005

Comparison of various bone marrow fractions in the ability to participate in vascular remodeling after mechanical injury.

In contrast to conventional assumption, recent reports propose the possibility that hematopoietic stem cells (HSCs) may have broader potential to differentiate into various cell types. Here, we tested the pluripotency of HSCs by comparing vascular lesions induced by mechanical injury after bone marrow reconstitution with total bone marrow (TBM) cells, c-Kit+ Sca-1+ Lin- (KSL) cells, or a single HSC cell (Tip-SP CD34-KSL cell, CD34- c-Kit+ Sca-1+ Lin- cell with the strongest dye-efflux activity) harboring green fluorescent protein (GFP). The lesions contained a significant number of GFP-positive cells in the TBM and KSL groups, whereas GFP-positive cells were rarely detected in the HSC group. These results suggest that transdifferentiation of a highly purified HSC seems to be a rare event, if it occurs at all, whereas bone marrow cells including the KSL fraction can give rise to vascular cells that substantially contribute to repair or lesion formation after mechanical injury.

Animals↗
PubMed2004

A serum amyloid A and LDL complex as a new prognostic marker in stable coronary artery disease.

BACKGROUND: Although some reports have indicated that acute phase proteins such as C-reactive protein (CRP) and serum amyloid A (SAA) can predict the prognosis in patients with acute coronary syndrome, the value of these markers in patients with stable coronary artery disease (CAD) still remains obscure. Therefore, our aim was to determine the prognostic value of inflammatory markers in patients with stable coronary artery disease. METHODS AND RESULTS: We conducted a prospective cohort study in 140 consecutive patients with stable coronary artery disease who had at least one coronary stenosis more than 50% in diameter seen on diagnostic coronary angiography (CAG). We determined serum levels of the SAA/LDL complex as a new marker in addition to CRP and SAA. Serum levels of the SAA/LDL complex were measured by a sandwich enzyme-linked immunosorbent assay (ELISA). End-points were defined as cardiac death, myocardial infarction, cerebral infarction, and coronary revascularization. End-point events occurred in 21 patients (2 death from myocardial infarction, 2 cerebral infarction, and 17 revascularization). Age (year) (OR = 1.14, CI: 1.05-1.25), diabetes mellitus (OR = 3.50, CI: 1.08-11.40), triglyceride (10mg/dl) (OR = 1.12, CI: 1.01-1.23) and SAA/LDL complex (10 microg/ml) (OR = 2.32, CI: 1.05-4.70) were independently related to the events. A reconstitution experiment suggested that the SAA/LDL complex is derived by oxidative interaction between SAA and lipoproteins. CONCLUSIONS: The SAA/LDL complex reflects intravascular inflammation directly and can be a new marker more sensitive than CRP or SAA for prediction of prognosis in patients with stable coronary artery disease.

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PubMed2004

Soft plaque detected on intravascular ultrasound is the strongest predictor of in-stent restenosis: an intravascular ultrasound study.

AIMS: Although various predictors of in-stent restenosis (ISR) have been reported, the subject of parameters relating to ISR on intravascular ultrasound (IVUS) still leaves room for discussion. The aim of this study was to clarify the strongest predictors of ISR using IVUS. METHODS AND RESULTS: Ninety-two native coronary lesions undergoing single bare-metallic stent implantation were investigated retrospectively. We classified them into the ISR (n=46) and non-ISR (n=46) groups using quantitative coronary angiography. On serial IVUS studies, plaque morphology, and areas and volumes of each component in vessel were evaluated. Among all parameters, diabetes mellitus and soft plaque appearing hypoechoic on IVUS were associated with ISR. By multivariate analysis, soft plaque was the only independent predictor of ISR (p=0.0057). Compared with non-soft plaque, soft plaque had a larger plaque reduction rate (-7.1% vs. -1.6%, p=0.0613) and smaller percent plaque volume (53.0% vs. 55.5%, p=0.0273) after stenting. Conversely, soft plaque had a larger neointimal area (4.39 vs. 3.33 mm2, p=0.0437) and percent plaque area (80.5% vs. 75.1%, p=0.0503) at follow-up. CONCLUSION: Soft plaque detected on IVUS was the strongest predictor of ISR. Soft plaque was compressed more easily by stenting, however, causing more proliferation of neointima subsequently and resulted in a worse prognosis.

Aged↗
PubMed2004

[Development of blood examination method of serum amyloid A and LDL complex, and clinical application to prediction of cardiovascular event].

In recent years, it has been reported that the acute-phase proteins C-reactive protein(CRP) and serum amyloid A(SAA), the sera levels of which are elevated in inflammation, are also elevated in coronary artery disease such as acute myocardial infarction. Also, high-sensitivity CRP assay is thought to be useful in predicting the prognosis of coronary heart disease. While investigating complexes of acute-phase proteins and low-density lipoprotein(LDL), we found a complex of LDL and SAA(SAA/LDL complex). The SAA/LDL complex in blood are formed from LDL and HDL by an oxidation reaction. Therefore, we developed an ELISA using anti-human SAA antibody and anti-human apoB, and determined a new method for measuring SAA/LDL complex in sera. We evaluated SAA/LDL complex as a new marker for prediction of prognosis in addition to the ordinary markers in consecutive 140 patients with stable coronary heart disease who had at least 1 coronary artery stenosis more than 50% in diameter at the diagnostic coronary angiography. Of these 140 patients, 2 developed fatal myocardial infarction, 2 cerebral infarction, and 17 angina pectoris requiring coronary revascularization therapy during 1 year and 6 months after blood examinations. The SAA/LDL complex value in this EVENT group of 21 patients was significantly higher than that in the control group of 119 individuals. High-sensitivity CRP (hs-CRP) assay and SAA measurement showed no significant difference between the 2 groups. The SAA/LDL complex reflects intravascular inflammation directly and can be a new marker more sensitive than hs-CRP or SAA for prediction of prognosis in patients with stable coronary artery disease.

Acute-Phase Proteins↗
PubMed2004

[Sex differences in coronary atherosclerosis: coronary angiography and intravascular ultrasonography].

OBJECTIVES: Women have higher mortality and frequency of complications compared with men after coronary intervention. Possible differences in coronary atherosclerosis between men and women were investigated. METHODS: The left anterior descending arteries of 214 patients (164 men, mean age 62.3 +/- 9.10 years; 50 women, mean age 67.8 +/- 7.76 years) were examined. Lesion length, reference diameter, percentage diameter stenosis and minimal lumen diameter were measured by quantitative coronary angiography. Vessel area, lumen area, percentage area stenosis, and remodeling index were measured by intravascular ultrasonography, and presence of calcification in the lesion was classified. These parameters were compared between men and women. RESULTS: There were no significant differences in quantitative coronary angiography, but intravascular ultrasonography showed calcification was more severe in women, vessel area was significantly smaller in women (13.25 +/- 4.21 vs 15.91 +/- 4.35 mm2, p = 0.004), and remodeling index was significantly lower in women (0.95 +/- 0.13 vs 1.04 +/- 0.18, p = 0.015). CONCLUSIONS: Vessel area measured by intravascular ultrasonography was significantly smaller in women, and calcification was more severe in women. Such factors may be involved in the higher mortality in women.

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PubMed2003

Arterial remodeling patterns before intervention predict diffuse in-stent restenosis: an intravascular ultrasound study.

OBJECTIVES: The aim of this retrospective study was to determine the predictors of diffuse in-stent restenosis (ISR) among the lesions causing the first ISR by intravascular ultrasound (IVUS) studies. BACKGROUND: Although some predictors of diffuse ISR have been reported, parameters on IVUS relating to diffuse ISR are not well characterized. METHODS: We classified 52 ISR lesions that had undergone successful stent implantation and led to restenosis into two types--focal and diffuse ISR--using quantitative coronary angiography. Restenosis was defined as > or =50% diameter stenosis, and diffuse ISR as lesion length > or =10 mm at follow-up. The remodeling index (RI) was defined as the vessel area at the target lesion divided by that of averaged reference segments. RESULTS: There were no significant differences in patient, angiographic, and procedural characteristics between the focal (n = 25) and diffuse (n = 27) ISR groups. Baseline RI was significantly greater in the diffuse ISR group (1.03 +/- 0.18 vs. 0.88 +/- 0.24, p = 0.0159). Negative remodeling, defined as RI <0.9, was detected in 60% of the focal ISR group and in only 26% of the diffuse ISR group. By logistic regression analysis, baseline RI was the only independent predictor of diffuse ISR (p = 0.0341). Moreover, volumetric analyses revealed that lesions developing into diffuse ISR had less capacity to compensate for further plaque growth. CONCLUSIONS: Among the first ISR lesions, baseline positive remodeling was the most powerful predictor of diffuse ISR. Measuring pre-interventional arterial remodeling patterns by IVUS may be helpful to stratify lesions at higher risk.

Aged↗
PubMed2003

Nifekalant hydrochloride, a novel class III antiarrhythmic agent, suppressed postoperative recurrent ventricular tachycardia in a patient undergoing coronary artery bypass grafting and the Dor approach.

A patient with 3-vessel coronary artery disease and left ventricular aneurysm underwent coronary artery bypass grafting combined with the Dor approach. Five days later, ventricular tachycardia following short-coupled ventricular premature contractions suddenly occurred and was not responsive to class IB drugs (lidocaine and mexiletine), requiring frequent electrical cardioversion. After the administration of a novel class III drug, nifekalant hydrochloride, this electrical storm of ventricular tachycardia was completely suppressed together with the disappearance of ventricular premature contractions. Nifekalant hydrochloride (MS-551), a pure K(+) channel blocker, might be effective for postoperative recurrent ventricular tachyarrhythmias that are refractory to other antiarrhythmic agents.

Aged↗
PubMed2002

Mechanisms of acute gain and late lumen loss after atherectomy in different preintervention arterial remodeling patterns.

The main mechanism of restenosis after directional coronary atherectomy (DCA) remains obscure. We investigated mechanisms of restenosis after DCA in different coronary artery remodeling patterns. DCA was performed in 51 de novo lesions. The lesions were evaluated by intravascular ultrasound (IVUS) before, immediately after, and 6 months after the procedure. According to the IVUS findings before DCA, we classified the lesions into the following 3 groups: (1) positive (n = 10), (2) intermediate (n = 25), and (3) negative (n = 16) remodeling. We measured lumen area, vessel area, and plaque area using IVUS before DCA, immediately after DCA, and at follow-up. Lumen area increase after DCA was mainly due to plaque area reduction in the positive and intermediate remodeling groups (90 plus minus 15% and 80 plus minus 25% increase in lumen area, respectively), whereas that in the negative remodeling group was due to both plaque area reduction (57 plus minus 22% increase in lumen area) and vessel area enlargement (43 plus minus 33% increase in lumen area). The plaque area increase correlated strongly with late lumen area loss in the positive and intermediate remodeling groups (r = 0.884, p <0.001; r = 0.626, p <0.001, respectively), but the decrease in vessel area was not correlated with lumen area loss. In contrast, both an increase in plaque area and a decrease in vessel area were correlated with late lumen area loss (r = 0.632, p = 0.009; r = 0.515, p = 0.041) in the negative remodeling group. Coronary artery restenosis after atherectomy was primarily due to an increase in plaque in the positive and/or intermediate remodeling groups. However, in the negative remodeling group, late lumen loss might have been caused by both an increase in plaque and vessel shrinkage.

Adult↗
PubMed2002

J wave and ST segment elevation in the inferior leads: a latent type of variant Brugada syndrome?

In a patient referred for the evaluation of non-sustained monomorphic ventricular tachycardia on Holter recordings, ventricular fibrillation was electrically induced during electrophysiologic study. Despite the absence of structural heart diseases, his ECG revealed J wave and ST segment elevation in the inferior leads, which showed circadian variation and were augmented by the sodium channel blocker, pilsicainide. This case might lead us to notice a new concept, a 'latent' type of variant Brugada syndrome, and these ECG findings and changes might serve as its diagnostic sign.

Adult↗