Naoya Mitsuba

Effects of lipid-lowering therapy with strong statin on serum polyunsaturated fatty acid levels in patients with coronary artery disease

Residual risk of cardiovascular events after treatment with stain might be explained in part because patients have low levels of n−3 polyunsaturated fatty acids (PUFA). We examined how lipid-lowering therapy with strong statin affected serum PUFA levels in patients with coronary artery disease. The study population consisted of 46 patients with coronary artery disease whose low-density lipoprotein (LDL) cholesterol was more than 100 mg/dl. Lipid-lowering therapy was performed with a strong statin including atorvastatin (n = 22), rosuvastatin (n = 9) or pitavastatin (n = 15). Serum PUFA levels were determined by gas chromatography. The treatment with strong statin decreased the sum of dihomo-γ-linolenic acid (DGLA) and arachidonic acid (AA) levels (195 ± 41 to 184 ± 44 μg/ml, P < 0.05) as well as the sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels (233 ± 71 to 200 ± 72 μg/ml, P < 0.001). These effects of strong statin resulted in a significant decrease in ratio of the sum of EPA and DHA levels to the sum of DGLA and AA levels (1.20 ± 0.27 to 1.10 ± 0.35, P < 0.05). The percent decrease in the LDL cholesterol level correlated significantly with that in the sum of EPA and DHA levels (r = 0.38, P < 0.01). In conclusion, our results showed that lipid-lowering therapy with strong statin mainly reduced n−3 PUFAs in proportion to the decrease in the LDL cholesterol level in patients with coronary artery disease.

Comparison of electrocardiographic findings between the midventricular ballooning form and apical ballooning form of takotsubo cardiomyopathy.

Several reports have recently described the variant form of takotsubo cardiomyopathy exhibiting midventricular ballooning. The purpose of this study was to assess electrocardiographic (ECG) findings on admission in patients with midventricular ballooning.

Evaluation of coronary microvascular function in patients with vasospastic angina.

AIM To investigate endothelium-dependent and -independent coronary microvascular functions in patients with vasospastic angina (VSA). METHODS Thirty-six patients with VSA (30 men and 6 women; mean age, 58 years) were enrolled in this study. VSA was defined as ≥ 90% narrowing of the epicardial coronary arteries on angiography performed during a spasm provocation test, presence of chest pain, and/or ST-segment deviation on an electrocardiogram (ECG). Patients (n = 36) with negative spasm provocation test results and those matched for age and sex were enrolled as a control group (nonVSA group). Low-dose acetylcholine (ACh; 3 μg/min) was infused into the left coronary ostium for 2 min during the spasm provocation test. Following the spasm provocation test, nitroglycerin (0.2 mg) was administered intracoronally. Coronary blood flow (was calculated from quantitative angiography and Doppler flow velocity measurements, and the coronary flow reserve was calculated as the ratio of coronary flow velocity after injection of adenosine triphosphate (20 μg) to the baseline value. Changes in the coronary artery diameter in response to ACh and nitroglycerin infusion were expressed as percentage changes from baseline measurements. RESULTS Body mass index was significantly lower in the VSA group than in the nonVSA group. The frequency of conventional coronary risk factors and the rate of statin use were similar between the 2 groups. The left ventricular ejection fraction as evaluated by echocardiography was similar between the 2 groups. The duration of angina was 9 ± 2 mo. The results of blood chemistry analysis were similar between the 2 groups. Low-dose ACh did not cause coronary spasms. The change in coronary artery diameter in response to ACh was lower in the VSA group (-1.4% ± 9.3%) than in the nonVSA group (3.1% ± 6.5%, P < 0.05), whereas nitroglycerin-induced coronary artery dilatation and coronary blood flow increase in response to ACh or coronary flow reserve did not differ significantly between the 2 groups. CONCLUSION These findings suggest that microvascular coronary function may be preserved despite endothelial dysfunction of the epicardial coronary arteries in patients with VSA.

Influence of left ventricular geometry on thallium-201 gated single-photon emission tomographic findings in patients with known or suspected coronary artery disease.

BackgroundRecent studies have shown good correlations between echocardiography and Tl-201 gated single-photon emission computed tomography (SPECT) for the assessment of left ventricular volumes and ejection fraction. We assessed how left ventricular geometry affected correlations between these values measured by the 2 methods in patients with known or suspected coronary artery disease.Methods and resultsThere were 109 patients with normal left ventricular geometry, 20 patients with concentric remodeling, 32 patients with eccentric hypertrophy and 28 patients with concentric hypertrophy. In all 4 groups, there were good correlations between end-diastolic volume (EDV) and end-systolic volume (ESV) values measured by echocardiography and quantitative gated SPECT (QGS). EDV and ESV values measured by QGS were significantly underestimated than those measured by echocardiography except for ESV in eccentric hypertrophy. In all 4 groups, ejection fraction (EF) value measured by echocardiography significantly correlated with that measured by QGS, but Bland–Altman plot showed a proportional error. EF value measured by QGS was likely to be overestimated when EF value increased from the median value, and to be underestimated when EF value decreased from the median value especially in concentric remodeling.ConclusionsTl-201 gated SPECT is a useful tool for the assessment of left ventricular volumes and function, but it requires methodological considerations according to left ventricular geometry.

Impaired coronary microvascular endothelial function in men with metabolic syndrome

AIM To assess coronary endothelial function of conduit and resistance vessels in patients with metabolic syndrome (MS). METHODS Seventy-eight men (mean age, 57 years) with chest pain and angiographically normal coronary arteries were included in the study. Patients with coronary spastic angina were excluded. Changes in coronary artery diameter and coronary blood flow (CBF) in response to acetylcholine (ACh) were determined using quantitative coronary angiography and Doppler velocity measurements. Coronary flow reserve was calculated as the ratio of coronary blood velocity after adenosine triphosphate infusion relative to baseline values. Patients were divided into two groups based on the presence or absence of MS. RESULTS There were 24 patients in the MS group (31%). The increase in CBF in response to ACh infusion was impaired in the MS group (P < 0.0001) compared to the non-MS group, whereas changes in coronary artery diameter in response to ACh infusion did not differ between the two groups. Multivariate regression analysis revealed that MS was a significant factor associated with the lesser change in CBF induced by ACh infusion at 30 μg/min (P < 0.0001, r(2) = 0.46). CONCLUSION Coronary endothelial dysfunction was present at the level of resistance vessels but not conduit vessels in the MS patients included in our study.

Effects of aliskiren on the fibrinolytic system in patients with coronary artery disease receiving angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker

Aliskiren is a novel blood pressure-lowering agent acting as an oral direct renin inhibitor. We evaluated the effects of aliskiren on the fibrinolytic system in patients with coronary artery disease who were receiving angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs). We studied 17 patients with coronary artery disease whose systolic blood pressure was more than 130 mmHg despite treatment with ACEIs or ARBs. Aliskiren (150 mg) was added to ACEIs or ARBs, and was continued for 6 weeks. Aliskiren significantly decreased systolic blood pressure (140 ± 6–128 ± 8 mmHg, P < 0.001) and plasma renin activity (1.8 ± 2.3–0.6 ± 0.9 ng/ml/h, P < 0.01) after 6 weeks. However, it did not affect plasminogen activator inhibitor-1 (28.8 ± 14.5–30.6 ± 13.6 ng/ml, P = 0.84), fibrinogen (305 ± 72 vs 301 ± 71 mg/dl, P = 0.33), or D-dimer (0.49 ± 0.24–0.51 ± 0.28 μg/ml, P = 0.70) levels. Our data suggested that patients receiving ACEIs or ARBs would not be expected to have any changes in biomarkers of the fibrinolytic system with additional pharmacologic inhibition of the renin–angiotensin–aldosterone system.

Effects of low-dose pioglitazone on glucose control, lipid profiles, renin-angiotensin-aldosterone system and natriuretic peptides in diabetic patients with coronary artery disease

Background: Pioglitazone ameliorates insulin resistance, but has an adverse effect of oedema that may result in subsequent heart failure, especially in diabetic patients with coronary artery disease. In this study, we evaluated the effects of low-dose pioglitazone on glucose control, lipid profiles, renin-angiotensin-aldosterone (RAA) system and natriuretic peptides in diabetic patients with coronary artery disease. Methods and results: We studied 22 diabetic patients with coronary artery disease and more than 40% of left ventricular ejection fraction (LVEF). Patients were treated with 15 mg of pioglitazone for 12 weeks, in addition to their other hypoglycaemic agents. Pioglitazone significantly decreased fasting blood glucose (155.2±52.9 mg/dl to 131.1±38.4 mg/dl, p<0.01) and haemoglobin A1C (7.13±0.44 to 6.69±0.47, p<0.001). It did not affect low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, but significantly decreased triglyceride (115.6±28.8 mg/dl to 99.4±30.0 mg/dl, p<0.05) and atherogenic index of plasma (0.28±0.17 to 0.19±0.16, p<0.05). Pioglitazone did not affect plasma renin activity, plasma aldosterone, human atrial natriuretic peptide or N-terminal pro-brain natriuretic peptide. Conclusion: Our data suggested that low-dose pioglitazone was a safe and useful agent at least in diabetic patients with coronary artery disease and preserved LVEF.

External side-compression of radial artery: a simple technique for successful advancement of guidewires through the radial approach.

BACKGROUND The transradial approach has several pitfalls that include problems regarding the radial puncture and difficulties with the catheter technique. We evaluated whether external side-compression of radial artery was helpful to yield the success rate for advancement of guidewires under the presence of side branches or arterial tortuosity. METHODS AND RESULTS The study population consisted of 11 patients with unsuccessful advancement of guidewires into the brachial artery. In 7 patients, the J-tip hydrophilic guidewire was not advanced into the brachial artery because it always directed into the side branch. During external side-compression of radial artery at the culprit site with a finger of the second operator, the guidewire was successfully advanced into the brachial artery in all patients. In 4 patients, the guidewire was not advanced into the brachial artery because the radial artery was tortuous. During external side-compression of radial artery at the culprit site, the guidewire was successfully advanced into the brachial artery in 2 patients. In the remaining 2 patients in whom this attempt was unsuccessful, coronary angiography was performed through the right brachial artery. Overall success rate of this technique was 82%. CONCLUSION External side-compression of radial artery is an easy and feasible technique for difficulties in the advancement of guidewires due to the presence of side branches or arterial tortuosity.

Impact of Malondialdehyde-Modified Low-Density Lipoprotein on Tissue Characteristics in Patients With Stable Coronary Artery Disease – Integrated Backscatter-Intravascular Ultrasound Study –

BACKGROUND Malondialdehyde-modified low-density lipoprotein (MDA-LDL) is considered to play an essential role in plaque destabilization. We aimed to investigate the association between the tissue characteristics of culprit plaque assessed by integrated backscatter (IB)-intravascular ultrasound (IVUS) and the serum MDA-LDL levels in patients with stable coronary artery disease. METHODSANDRESULTS The study group consisted of 179 patients undergoing IB-IVUS during elective percutaneous coronary intervention. Patients were classified into 2 groups based on serum MDA-LDL level: low MDA-LDL group (<102 U/L, n=88) and high MDA-LDL group (≥102 U/L, n=91). Plaques in the high MDA-LDL group had higher %lipid (45.2±12.5% vs. 54.9±14.5%, P<0.001) and lower %fibrosis (43.0±9.1% vs. 36.4±11.4%, P<0.001) than did plaques in the low MDA-LDL group. Lipid-rich plaque (%lipid >60% or %fibrosis <30%) was significantly more frequently found in the high MDA-LDL group than in the low MDA-LDL group (14.3% vs. 39.8%, P<0.001). The incidence of MACE (cardiac death, myocardial infarction and/or hospitalization for heart failure) during 3 years was significantly higher in the high MDA-LDL group than in the low MDA-LDL group (6.6% vs. 15.9%, P=0.02). CONCLUSIONS Higher MDA-LDL might be associated with greater lipid and lower fibrous content, contributing to coronary plaque vulnerability. (Circ J 2016; 80: 2173-2182).

Effect of body mass index on the location of the right adrenal vein in patients with primary aldosteronism

Background: Variable location of the orifice of the right adrenal vein appears to be associated with a poor success rate of sampling, especially in less experienced hands. We described the spectrum of the location of the right adrenal vein, and identified the relation of its location to body mass index in patients with primary aldosteronism. Methods and results: The study population consisted of 95 patients with primary aldosteronism who underwent adrenal venous sampling. On the basis of the anterior view of the right adrenal venogram, the cranio-caudal level of the orifice of right adrenal vein was determined relative to vertebral bodies and disks. In 93 (98%) of the 95 patients, the orifice was located at a level ranging from the upper segment of T11 to the upper segment of L1. In the remaining two patients, it was located at the level of the lower segment of T10. High body mass index was associated with the higher level of the orifice of right adrenal vein. Conclusion: Our data suggested that the location of the orifice of right adrenal vein was largely related to body mass index in patients with primary aldosteronism.