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Katsutoshi Makino

Publications and source records attributed to Katsutoshi Makino.

9 recordsLinked to original sources
PubMed2006

Detection of coronary artery stenosis with whole-heart coronary magnetic resonance angiography.

OBJECTIVES: We sought to determine the diagnostic performance of whole-heart coronary magnetic resonance (MR) angiography for detecting significant coronary artery disease. BACKGROUND: The accuracy of whole-heart coronary MR angiography has not been determined in a large number of patients. METHODS: Three-dimensional coronary MR angiograms covering the entire heart were obtained during free breathing in 131 patients. Images were acquired during a patient-specific time window in the cardiac cycle with minimal motion of the coronary artery. Significant coronary artery disease was defined on X-ray coronary angiography as a diameter reduction of > or =50% in coronary arteries with a reference diameter of > or =2 mm. RESULTS: The acquisition of MR angiography was completed in 113 (86%) of 131 patients, with an imaging time averaged at 12.9 +/- 4.3 min. On a patient-based analysis, the sensitivity, specificity, positive and negative predictive value, and accuracy of MR angiography were 82% (95% confidence interval [CI] 69% to 91%), 90% (95% CI 79% to 96%), 88% (95% CI 74% to 95%), 86% (95% CI 75% to 93%), and 87% (95% CI 79% to 92%), respectively. These values in the individual segments were 78% (95% CI 68% to 85%), 96% (95% CI 95% to 97%), 69% (95% CI 60% to 77%), 98% (95% CI 96% to 98%), and 94% (95% CI 96% to 96%). CONCLUSIONS: Whole-heart coronary MR angiography allows for noninvasive detection of significant narrowing in coronary arterial segments with a diameter of > or =2 mm with moderate sensitivity and high specificity.

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PubMed2006

Impact of nicorandil to prevent reperfusion injury in patients with acute myocardial infarction: Sigmart Multicenter Angioplasty Revascularization Trial (SMART).

BACKGROUND: Nicorandil in conjunction with percutaneous coronary intervention (PCI) has been reported to reduce reperfusion injury events and improve cardiac function in patients with acute myocardial infarction (AMI). This multicenter study was undertaken to determine the effectiveness and optimal administration of nicorandil in AMI patients. METHODS AND RESULTS: Ninety-two patients with first AMI were randomly assigned to 1 of 3 groups: intracoronary administration of nicorandil (Group A), combined intravenous and intracoronary administration of nicorandil (Group B), and no nicorandil administration (Group C). The primary endpoint was a composite of the incidence of reperfusion-induced arrhythmia, chest pain, and no-reflow/slow-reflow. The secondary endpoint was the combined rate of improvement in the Thrombolysis in Myocardial Infarction frame count (cTFC) and ST resolution (STR). A significant difference was observed in the primary endpoint for Group B as compared with Group C (p<0.05). In the meantime, a significant improvement was shown in the secondary endpoint for Group B compared with Group C (p=0.04 and 0.006 for cTFC and STR, respectively). CONCLUSIONS: Combined intravenous and intracoronary administration of nicorandil reduces reperfusion injury during PCI and improves the cTFC and STR in AMI, and appears to be preferable to intracoronary administration alone.

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PubMed2005

Assessment of coronary arteries with total study time of less than 30 minutes by using whole-heart coronary MR angiography.

This study had institutional review board approval, and all patients gave informed consent. The purpose of this study was to prospectively evaluate the use of whole-heart three-dimensional (3D) coronary magnetic resonance (MR) angiography in patients suspected of having coronary artery disease. Whole-heart coronary MR angiography was performed in 39 patients (30 men and nine women; mean age, 63.9 years +/- 15.6 [standard deviation]) by using a steady-state free precession sequence with free breathing. Twenty patients (16 men and four women; mean age, 64.9 years +/- 11.7) also underwent conventional coronary angiography. MR angiography was successfully completed in 34 of 39 patients (87%); the average imaging time was 13.8 minutes +/- 3.8. Sensitivity and specificity of MR angiography for detecting significant stenosis were 82% (14 of 17 arteries) and 91% (39 of 43 arteries), respectively. Whole-heart coronary MR angiography with a navigator-gated steady-state sequence can enable reliable 3D visualization of the coronary arteries in patients suspected of having coronary artery disease.

Coronary Angiography↗
PubMed2005

Late gadolinium-enhanced magnetic resonance imaging in acute and chronic myocardial infarction. Improved prediction of regional myocardial contraction in the chronic state by measuring thickness of nonenhanced myocardium.

OBJECTIVES: We sought to determine serial changes of enhanced and nonenhanced tissue on late gadolinium-enhanced cardiac magnetic resonance (CMR) imaging in patients with a myocardial infarction (MI) and to assess whether thickness of nonenhanced myocardium can improve the detection of preserved contractile function in the chronic state. BACKGROUND: Previous studies demonstrated that enhancement on late gadolinium-enhanced CMR images indicates myocardial necrosis, and nonenhancement shows the presence of viable myocardium. METHODS: The CMR studies were performed within one week (scan 1) and more than five months (scan 2) after the onset of MI in 18 patients. The area and mean thickness of enhanced tissue and nonenhanced myocardium were measured by using a 30-segment model. Systolic wall thickening on cine CMR at scan 2 was assessed for evaluating regional contractile function. RESULTS: The amount of enhanced tissue significantly decreased from scan 1 to 2 (22.1 +/- 14.0 ml vs. 15.0 +/- 9.3 ml, p < 0.001). The averaged thickness of nonenhanced myocardium in the infarct segments significantly increased from scan 1 to 2 (5.2 +/- 3.0 mm vs. 6.6 +/- 3.2 mm, p < 0.001). Receiver operating characteristic analysis demonstrated that the measurement of thickness of nonenhanced myocardium, compared with measurement of percent transmural enhancement, had better diagnostic accuracy for predicting improved systolic wall thickening form scan 1 to 2 in dysfunctional segments (Az 0.650 vs. 0.594, p < 0.05). CONCLUSIONS: The amounts of enhanced tissue and nonenhanced myocardium significantly altered from the acute to chronic state in MI patients. The diagnostic performance of CMR imaging for detection of preserved contractile function can be significantly improved by measuring thickness of nonenhanced myocardium in MI patients.

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PubMed2005

Diagnostic accuracy of stress first-pass contrast-enhanced myocardial perfusion MRI compared with stress myocardial perfusion scintigraphy.

OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery prepared turbo fast low-angle shot (turbo FLASH) compared with stress myocardial perfusion scintigraphy. Recent studies show that first-pass contrast-enhanced myocardial perfusion MRI can provide noninvasive detection of low-limiting stenosis in the coronary artery. MATERIALS AND METHODS: First-pass contrast-enhanced MR images were acquired at rest and during stress in 40 patients with suspected coronary artery disease. All patients underwent thallium-201 SPECT without attenuation correction and coronary angiography. Two reviewers independently assigned one of five confidence grades without knowing the results of coronary angiography for receiver operating characteristic (ROC) analysis. Luminal stenosis >70% on coronary angiography was used as a reference standard. RESULTS: On coronary angiography, 70% or greater diameter stenosis of the coronary artery was observed in 21 (52.5%) of 40 patients. The areas under the ROC curve for detection of significant stenosis in the individual coronary artery were 0.86 (observer 1) and 0.84 (observer 2) for MRI. These values were 0.79 (observer 1, p = not significant) and 0.72 (observer 2, p = not significant) for 201Tl SPECT. CONCLUSION: The diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery-prepared turbo FLASH was comparable with that of stress 201Tl SPECT. Stress first-pass contrast-enhanced MRI is a noninvasive technique that can be used as an alternative to stress myocardial perfusion scintigraphy.

Contrast Media↗
PubMed2003

Acute myocardial infarction: myocardial viability assessment in patients early thereafter comparison of contrast-enhanced MR imaging with resting (201)Tl SPECT. Single photon emission computed tomography.

PURPOSE: To compare contrast material-enhanced magnetic resonance (MR) imaging with resting thallium 201 ((201)Tl) single photon emission computed tomography (SPECT) for predicting myocardial viability in patients early after acute myocardial infarction. MATERIALS AND METHODS: Inversion-recovery contrast-enhanced MR images and resting (201)Tl SPECT images were obtained in 22 patients after acute myocardial infarction. The (201)Tl SPECT images were obtained 4.3 days +/- 0.2 (standard error) after the onset of myocardial infarction. Contrast-enhanced MR imaging was performed 7.9 days +/- 1.6 after (201)Tl SPECT. Transmural extent of hyperenhancement on contrast-enhanced MR images and regional (201)Tl activity were quantitatively analyzed with a 12-segment model. Regional wall thickening on follow-up cine MR images obtained 67 days +/- 17 after contrast-enhanced MR imaging was used as an index for myocardial viability. Statistical analyses were performed with the chi(2) and two-tailed Student t tests. RESULTS: Both contrast-enhanced MR and resting (201)Tl SPECT images showed significant correlations with regional wall thickening on follow-up cine MR images. The sensitivity, specificity, and accuracy of contrast-enhanced MR imaging in the prediction of viable myocardium were significantly higher than those of resting (201)Tl SPECT (98.0% vs 90.3%, P <.01; 75.0% vs 54.4%, P <.05; and 92.0% vs 81.1%, P <.001, respectively). CONCLUSION: Delayed contrast-enhanced MR imaging can help predict myocardial viability as seen on follow-up cine MR images after acute myocardial infarction, with significantly improved sensitivity, specificity, and accuracy in comparison with those of resting (201)Tl SPECT.

Female↗
PubMed2002

Differences in fatty acid metabolic disorder between ischemic myocardium and doxorubicin-induced myocardial damage: assessment using BMIPP dynamic SPECT with analysis by the Rutland method.

UNLABELLED: Dynamic myocardial SPECT data acquired with 15-(123)I-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) were analyzed by the Rutland method. The relative time-activity curves generated from dynamic SPECT in normal control subjects were compared with similar curves from patients with established ischemic heart disease (IHD) and doxorubicin-induced myocardial damage (DxMD). Comparison of such time-activity curves may provide some indirect information concerning qualitative differences in BMIPP metabolism. METHODS: Thirteen patients with various malignancies who received doxorubicin, 16 patients with IHD, and 15 normal control subjects were examined. Immediately after the bolus injection of BMIPP, dynamic data acquisition with a 3-head SPECT system was started and continued for 15 min. Using the time-activity curves of the myocardium as the output function (Mo(t)) and the time-activity curves of the left ventricular cavity as the input function (B(t)), the Rutland equation was calculated: Mo(t)/B(t) = F + K integral B(t)dt/B(t), where F is the blood - background subtraction factor and K is the uptake constant. The duration of the linear portion in this equation and the K values were evaluated. RESULTS: Mo(t)/B(t) was plotted against integral B(t)dt/B(t). Mo(t)/B(t) showed a good linear correlation with integral B(t)dt/B(t) from 30 s to 230 +/- 57 s in normal control subjects. The duration of this linearity was prolonged to 317 +/- 79 s in DxMD (P = 0.0014) and shortened to 182 +/- 58 s in IHD (P = 0.039). The mean K value was 0.0740 +/- 0.0184 in normal control subjects, significantly higher than the K values of 0.0599 +/- 0.0148 in DxMD patients (P = 0.026) and 0.0497 +/- 0.0189 (P = 0.0020) in IHD patients. CONCLUSION: Analysis of BMIPP dynamic SPECT data by the Rutland method is useful for detecting qualitative differences in BMIPP metabolism in various types of myocardial damage. It is speculated that the fatty acid metabolic disorder is characterized by a delay in metabolism in DxMD and by increased backdiffusion in IHD.

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