Kenshi Fujii

Sakurabashi Watanabe Hospital, Ōsaka, Ōsaka, Japan

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Publications (80)329.22 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: We report on two patients with sirolimus-eluting stent (SES) restenosis lesions who showed highly echolucent regions by optical coherence tomography (OCT) and who could be assessed histologically after removal by directional coronary atherectomy (DCA). One restenosis lesion had a bilayer structure of hyperechoic outer layers and highly echolucent inner layers on OCT images and histologically exhibited myxomatous neointima tissue in the highly echolucent regions; another restenosis case showed patchy and highly echolucent regions throughout the layers and its histology revealed fibrin thrombosis. We should be aware that patterns of echolucent on OCT images may have various histology. OCT allows the visualization of fine lesions that conventional intravascular ultrasound (IVUS) cannot provide. The OCT images of drug-eluting stent restenosis lesions often show echolucent regions [Shuzoh et al., EuroInterv 2006;1:484]. However, no histological study of the lesions has been reported to date. Here we report on two patients with SES restenosis lesions that showed highly echolucent regions by OCT and that could be assessed histologically after removal by DCA.
    Catheterization and Cardiovascular Interventions 09/2009; 75(6):961-3. · 2.51 Impact Factor
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    ABSTRACT: It is controversial as to whether nicorandil would have cardioprotective effects in patients with acute myocardial infarction (AMI) who are undergoing reperfusion therapy. A meta-analysis was performed to study the impacts of nicorandil on functional outcomes after AMI. Randomized prospective cohort or retrospective cohort publications were identified up to October 2007 by means of a computer search of MEDLINE and Google Scholar databases. Two reviewers checked the quality of the studies and extracted data regarding patient and disease characteristics, study design, functional parameters such as Thrombolysis In Myocardial Infarction (TIMI) flow grade after reperfusion, left ventricular ejection fraction (LVEF) and left ventricular end-diastolic volume index (LVEDVI). Seventeen studies were included for the meta-analysis in this study. Nicorandil treatment reduced the incidence of TIMI flow grade < or =2 in 1,337 patients of 10 studies (risk ratio 0.63; 95% confidence interval (CI) 0.44 to 0.91). While no beneficial effect was observed on the peak creatine kinase value, nicorandil treatment was associated with greater LVEF (by 3.7%, 95%CI 1.8 to 5.7%), and lower LVEDVI (by 8.8 ml/kg, -14.4 to -3.3 ml/kg) in 905 patients of 11 studies. The meta-analysis demonstrated that nicorandil treatment adjunctive to reperfusion therapy has beneficial effects on microvascular function and on functional recovery after AMI.
    Circulation Journal 04/2009; 73(5):925-31. · 3.58 Impact Factor
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    ABSTRACT: This study sought to investigate the timing and amount of embolic particles generation during the percutaneous coronary intervention (PCI) procedure and studied the relationship between embolic burden and coronary blood flow and myocardial damage. Distal embolization is a major complication of PCI. The Doppler guidewire (DGW) can detect the embolic particles as high-intensity transient signals (HITS) during the PCI procedure. We prospectively studied 37 patients with acute myocardial infarction (MI). Under monitoring with the DGW, we performed first and second balloon angioplasty, followed by stenting and post-high-pressure dilatation. Left ventricular ejection fraction (LVEF) (%) and regional wall motion (RWM) (standard deviation/chord) were measured on days 1 and 22. The HITS were detected in 35 of 37 patients. The number of HITS was the greatest after stenting (16 +/- 18) followed by first balloon inflation (5 +/- 4). There was a significant correlation between the total number of HITS and the corrected Thrombolysis In Myocardial Infarction frame count (r = 0.52, p = 0.003) and a significant weak inverse correlation between the total number of HITS and changes in LVEF and RWM (r = 0.37, p = 0.03 and r = 0.35, p = 0.04, respectively). Distal embolization is common during PCI in patients with acute MI, and the majority of HITS were observed after stenting. An increase in the total number of HITS is associated with reduced coronary blood flow, and is weakly associated with poor recovery of left ventricular function.
    JACC. Cardiovascular Interventions 07/2008; 1(3):268-76. · 1.07 Impact Factor
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    ABSTRACT: This case report describes a patient with incessant atrial tachycardia (AT) who underwent catheter ablation. During electrophysiological study, the stable AT circuit spontaneously shifted to unstable AT due to intermittent frequent firing from the right inferior pulmonary vein (PV) after termination of cavo-tricuspid isthmus dependent atrial flutter. A macroreentrant AT circuit was observed after electrical isolation of right inferior PV potentials. These findings suggest that the presence of rapid activated firing is likely to be associated with the development of instability in the AT circuit. This may lead to a greater understanding of the physiology of atrial tachyarrhythmia as a simple clinical model.
    Journal of Arrhythmia 01/2008; 24(3):149-155.
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    ABSTRACT: Recently, an association between minimally elevated cardiac troponin levels and cardiovascular risk in the general population has been reported. However, the prevalence and clinical importance of elevated cardiac troponin T (cTnT) levels remain unclear in patients with histories of myocardial infarction (MI). In this study, 1,807 consecutive patients with ST-segment elevation MIs were prospectively studied (77.1% men; mean age 64.4 years). Venous blood samples were obtained in the chronic stage of MI (28 +/- 7 days after onset), and serum cTnT levels were determined. During the average follow-up of 1,042 days, 84 patients died and 83 had nonfatal reinfarctions. Patients with cTnT levels in the highest quartile (> or = 0.040 ng/ml [n = 353]) had a higher incidence of all-cause death (8.2% vs 5.2%, p = 0.049) and nonfatal reinfarction (8.3% vs 5.1%, p = 0.048) than patients with cTnT levels from the lower 3 quartiles (<0.040 ng/ml [n = 1,064]). Multivariate Cox regression analysis revealed that a minimally elevated cTnT level (> or =0.040 ng/ml) was a significant predictor of all-cause mortality (hazard ratio 1.79, 95% confidence interval 1.10 to 2.90, p <0.02) and nonfatal reinfarction (hazard ratio 1.50, 95% confidence interval 1.13 to 2.20, p <0.03). Subgroup analysis showed that an elevated cTnT level was also a predictor of all-cause mortality and nonfatal reinfarction in patients without heart failure. In conclusion, minimally elevated cTnT levels in the chronic stage of MI predicted long-term adverse clinical outcomes.
    The American Journal of Cardiology 12/2007; 100(12):1723-6. · 3.21 Impact Factor
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    ABSTRACT: Myocardial contrast echocardiography (MCE) visualizes myocardial perfusion abnormalities after acute myocardial infarction. However, the limited view of 2-dimensional echocardiography reduces its ability to estimate perfusion abnormalities, especially in the subendocardial region. Three-dimensional echocardiography provides images of the left ventricular endocardium directly. This study was conducted to evaluate the ability of 3-dimensional MCE to assess abnormalities of subendocardial perfusion. Intracoronary 2- and 3-dimensional MCE was performed after primary percutaneous coronary intervention in 47 patients with acute myocardial infarction. Myocardial perfusion within the risk area was evaluated as good, poor, or no reflow on 2-dimensional MCE or as good, poor, or no myocardial opacification in endocardium on 3-dimensional MCE. The 2 methods showed different distributions of perfusion patterns: good, poor, and no reflow on 2-dimensional MCE in 31 (66%), 9 (19%), and 7 (15%) patients and good, poor, and no myocardial opacification in endocardium on 3-dimensional MCE in 17 (36%), 16 (34%), and 14 (20%) patients, respectively. Although only 19 patients (61%) with good reflow on 2-dimensional MCE showed myocardial perfusion grade 3 on angiography, 16 of 17 patients (94%) with good myocardial opacification in endocardium on 3-dimensional MCE showed myocardial perfusion grade 3. Although there were no significant differences in peak creatine kinase among the 3 subsets classified by 2-dimensional MCE, peak creatine kinase showed significant differences not only among the 3 groups but also among the subsets classified by 3-dimensional MCE. Classification by 3-dimensional MCE also predicted regional wall motion after 4.6 +/- 2.7 months, with significant differences between each pair of groups, whereas there was significant overlap of these values between the group with poor reflow and other 2 groups by 2-dimensional MCE. In conclusion, 3-dimensional MCE is a feasible way to assess subendocardial perfusion and predicts infarct size and functional recovery more precisely than 2-dimensional MCE.
    The American Journal of Cardiology 12/2007; 100(10):1502-10. · 3.21 Impact Factor
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    ABSTRACT: Patients who have acute myocardial infarction remain at major risk of cardiovascular events. We aimed to assess the effects of either human atrial natriuretic peptide or nicorandil on infarct size and cardiovascular outcome. We enrolled 1216 patients who had acute myocardial infarction and were undergoing reperfusion treatment in two prospective, single-blind trials at 65 hospitals in Japan. We randomly assigned 277 patients to receive intravenous atrial natriuretic peptide (0.025 microg/kg per min for 3 days) and 292 the same dose of placebo. 276 patients were assigned to receive intravenous nicorandil (0.067 mg/kg as a bolus, followed by 1.67 microg/kg per min as a 24-h continuous infusion), and 269 the same dose of placebo. Median follow-up was 2.7 (IQR 1.5-3.6) years for patients in the atrial natriuretic peptide trial and 2.5 (1.5-3.7) years for those in the nicorandil trial. Primary endpoints were infarct size (estimated from creatine kinase) and left ventricular ejection fraction (gauged by angiography of the left ventricle). 43 patients withdrew consent after randomisation, and 59 did not have acute myocardial infarction. We did not assess infarct size in 50 patients for whom we had fewer than six samples of blood. We did not have angiographs of left ventricles in 383 patients. Total creatine kinase was 66,459.9 IU/mL per h in patients given atrial natriuretic peptide, compared with 77,878.9 IU/mL per h in controls, with a ratio of 0.85 between these groups (95% CI 0.75-0.97, p=0.016), which indicated a reduction of 14.7% in infarct size (95% CI 3.0-24.9%). The left ventricular ejection fraction at 6-12 months increased in the atrial natriuretic peptide group (ratio 1.05, 95% CI 1.01-1.10, p=0.024). Total activity of creatine kinase did not differ between patients given nicorandil (70 520.5 IU/mL per h) and controls (70 852.7 IU/mL per h) (ratio 0.995, 95% CI 0.878-1.138, p=0.94). Intravenous nicorandil did not affect the size of the left ventricular ejection fraction, although oral administration of nicorandil during follow-up increased the left ventricular ejection fraction between the chronic and acute phases. 29 patients in the atrial natriuretic peptide group had severe hypotension, compared with one in the corresponding placebo group. Patients with acute myocardial infarction who were given atrial natriuretic peptide had lower infarct size, fewer reperfusion injuries, and better outcomes than controls. We believe that atrial natriuretic peptide could be a safe and effective adjunctive treatment in patients with acute myocardial infarction who receive percutaneous coronary intervention.
    The Lancet 11/2007; 370(9597):1483-93. · 39.06 Impact Factor
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    ABSTRACT: Insertion of intracoronary thrombectomy (ICT) devices, as a precedent to percutaneous coronary intervention (PCI), theoretically could have a beneficial effect on the outcome in patients with acute myocardial infarction. To examine whether ICT was associated with a lower 30-day mortality rate in patients with acute myocardial infarction, we studied 3,913 patients who underwent PCI within 24 hours after onset. A total of 990 patients (25.3%) were treated with ICT before PCI. The 30-day mortality rate was lower in the patients receiving ICT than in those without (3.7% vs 6.2%, p = 0.004), but this beneficial effect disappeared after adjustment for baseline characteristics (hazard ratio [HR] 0.658, p = 0.166). We also divided the patients into tertiles according to the Thrombolysis In Myocardial Infarction (TIMI) risk score. After adjustment for baseline characteristics, ICT was associated with a lower 30-day mortality rate in patients from the highest TIMI risk score tertile (HR 0.407, p = 0.029), but not in patients from the lower 2 tertiles. ICT was also an independent predictor of a lower 30-day mortality risk in patients aged > or =70 years (HR 0.239, p = 0.007), patients with diabetes mellitus (HR 0.275, p = 0.039), and those with stent implantation (HR 0.437, p = 0.034). In conclusion, in selected patients with high TIMI risk scores, an age > or =70 years, diabetes mellitus, or stenting, ICT is associated with a lower 30-day mortality rate.
    The American Journal of Cardiology 10/2007; 100(8):1212-7. · 3.21 Impact Factor
  • Atsunori Okamura, Hiroshi Ito, Kenshi Fujii
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    ABSTRACT: Angiographic no-reflow occurs occasionally during percutaneous coronary intervention in patients with acute myocardial infarction. Recently, we reported that coronary embolic particles can be detected as high-intensity transient signals with the Doppler guidewire. In the present study, the Doppler guidewire revealed that embolization of a cluster of embolic particles liberated by balloon inflation was responsible for angiographic no-reflow.
    The Journal of invasive cardiology 08/2007; 19(7):E210-3. · 1.57 Impact Factor
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    ABSTRACT: Aims: We have sometimes encountered difficulty in stent positioning, and managed to achieve optimal positioning of the stent by luck when there was extensive movement of the stent delivery system in association with the cardiac cycle. We assessed the safety and efficacy of rapid ventricular pacing in order to achieve precise positioning of the stent in this percutaneous coronary intervention (PCI) situation.Methods and results: Among 363 patients who underwent PCI, difficulty in positioning of the stent was encountered in 7 consecutive patients due to extensive movement of the stent delivery system. We applied rapid ventricular pacing in these 7 patients. We measured the length of motion of the stent delivery system relative to the coronary artery and systolic blood pressure before and under rapid ventricular pacing at a rate of 160 min-1. The extent of motion was markedly reduced by rapid ventricular pacing (7.3+/-2.6 mm to 1.7+/-0.6 mm; p<0.001). Systolic blood pressure was decreased slightly by rapid ventricular pacing (116+/-15 mmHg to 90+/-7 mmHg; p=0.002), but there were no cases of haemodynamic degeneration or ventricular arrhythmia. Conclusions: Rapid ventricular pacing is a safe and promising option for precise stent positioning, when movement of the stent delivery system prevents precise deployment.
    EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 08/2007; 3(2):239-42. · 3.17 Impact Factor
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    ABSTRACT: We detected embolic particles liberated from plaque during percutaneous coronary intervention (PCI) as high-intensity transient signals (HITS) with a Doppler guidewire and studied their impact on coronary flow dynamics and the myocardium in patients with stable angina pectoris. These embolic particles during PCI may cause myocardial injury. However, this was difficult to confirm because it was impossible to detect embolic particles. We performed balloon angioplasty followed by stenting in 31 patients while monitoring coronary flow velocity. After PCI, we measured average peak velocity at baseline and after infusion of adenosine 5'-triphosphate to calculate coronary flow velocity reserve (CFVR) and coronary resistance index (CRI). In patients with PCI to the left coronary artery (n = 21), we calculated relative CFVR as the ratio of CFVR in the target vessel to that in the reference vessel. We measured cardiac troponin T (cTnT) the day after PCI. HITS were detected in 27 (87%) of 31 patients and the majority were observed after stenting. The total number of HITS was correlated with CRI (r = 0.36, P = 0.049) or relative CFVR (r = 0.65, P = 0.0036) but not with CFVR (r = 0.048, P = 0.82). Thirteen patients showed elevated cTnT (range, 0.05-0.31 ng/ml) and the total number of HITS was greater in those with elevated cTnT than in those without elevated cTnT (24 +/- 9 vs. 10 +/- 7, P = 0.0007). Embolic particles are frequently observed during PCI to stable plaque and the majority are liberated after stenting. There appears to be a quantitative relationship between amounts of HITS and coronary microvessel dysfunction and minor myocardial injury.
    Catheterization and Cardiovascular Interventions 03/2007; 69(3):425-31. · 2.51 Impact Factor
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    ABSTRACT: Atrial fibrillation (AF) may originate from catecholamine-sensitive vein of Marshall (VOM) or its ligament in addition to pulmonary veins (PVs). The anatomy of VOM and its relation to arrhythmogenic foci in the left atrium are unknown. We studied the anatomy of VOM and its relation to foci in patients with AF. The study population consisted of 100 patients with AF (mean age, 62 years; chronic AF, n = 15). AF sources were determined at baseline and after isoproterenol administration without sedation. VOM was identified by balloon-occluded coronary sinus (CS) angiography. We determined its anatomy in relation to left PVs. VOM was visualized in 73 patients (73%). Ninety-seven patients had 269 arrhythmogenic foci (PV, n = 77; non-PV, n = 48). Non-PV foci included left atrial posterior wall (24, 9%), left lateral area (12, 4.5%), roof (6, 2.2%), superior vena cava (28, 10.4%), crista terminalis (8, 3.0%), CS (10, 3.7%), and others (10, 3.7%). The incidence of PV foci in the left superior PV (LSPV) was significantly higher in patients with well-developed VOM than in those without (66% vs 42%, P < 0.05). Twenty-eight patients had 30 non-PV foci around the LSPV ostium. We successfully ablated the non-PV foci at the distal end of VOM in 11 patients. The ends of the VOM branches were good markers to search for non-PV foci. Seven of 11 (64%) patients with successful ablation of non-PV foci were free from arrhythmia, whereas only 6 of 17 (35%) were free from arrhythmia in those with residual non-PV foci. To determine VOM anatomy is important to identify non-PV foci around the ends of VOM.
    Journal of Cardiovascular Electrophysiology 11/2006; 17(10):1062-7. · 3.48 Impact Factor
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    ABSTRACT: High-resolution real-time 3-dimensional echocardiography (RT3DE) allows observation of the left ventricular endocardial surface in vivo. This study was performed to characterize the endocardial surface structure and its contractile function in the myocardial infarction (MI) zone in relation to the healing stage. RT3DE was performed in 90 subjects: 10 normal subjects, 50 patients with Q-wave MI 2 weeks after onset (acute MI), and 30 patients >2 months after onset (healed MI). Recordings of the left ventricular endocardial surface allowed observation of the endocardial structure in 76 patients (84%) from the apical window. The endocardial surface of normal myocardium has rough muscle folds that shrink during systole, implying endocardial contraction. In acute MI, the endocardial surface had lost systolic contraction, but appeared as normal surface structure and showed normal acoustic intensity. The endocardial surface of healed MI showed loss of systolic contraction, disappearance of folds (smooth surface), and high acoustic intensity. The frequencies of smooth surface and highest acoustic intensity were significantly higher in healed MI than acute MI (72% vs 32%, 68% vs 37%, p <0.05, respectively). Loss of systolic endocardial contraction was a common finding of Q-wave MI irrespective of the healing stage, and we could roughly estimate the size of the MI from the spatial extent of the noncontractile zone with reasonable reproducibility (r = 0.90, p <0.001). In conclusion, RT3DE is a new modality that allows observation of the structure and contraction of the endocardial surface of the left ventricular wall. We can make rough estimation of the size of the MI and its healing stage from endocardial observation with RT3DE.
    The American Journal of Cardiology 06/2006; 97(11):1578-81. · 3.21 Impact Factor
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    ABSTRACT: Effective regurgitant orifice area is a useful index of the severity of mitral regurgitation (MR). The calculation of regurgitant orifice area using the proximal isovelocity surface area (PISA) method has some technical limitations. Three-dimensional reconstruction of the MR jet was performed using the Live 3D system on a Sonos 7500 to measure regurgitant orifice area directly in 109 cases of MR. Regurgitant orifice area was also measured by quantitative 2-dimensional echocardiography and by the PISA method. To analyze the shape of the regurgitant orifice, the ratio of the long axis to the short axis of the orifice (the L/S ratio) was calculated. Regurgitant orifice area on 3-dimensional echocardiography showed an almost identical correlation with that obtained by quantitative echocardiography (r = 0.91, p <0.0001, slope = 0.97) regardless of the L/S ratio. It was also significantly correlated with orifice area obtained using the PISA method (r = 0.93, p <0.0001). However, orifice area on 3-dimensional echocardiography was significantly larger than that obtained using the PISA method in the whole study group and in the 62 cases of MR with L/S ratios >1.5, whereas the correlation was almost identical in cases of MR with L/S ratios < or =1.5. Orifice area obtained using the PISA method also underestimated that obtained by quantitative echocardiography in cases of MR with L/S ratios >1.5. Three-dimensional echocardiography provided robust values independent of the eccentricity of the MR jet or of cardiac rhythm. In conclusion, the direct measurement of the regurgitant orifice area of MR with 3-dimensional Doppler echocardiography could be a promising method to overcome the limitations of the PISA method, especially in cases of MR with elliptic orifice shapes.
    The American Journal of Cardiology 06/2006; 97(11):1630-7. · 3.21 Impact Factor
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    ABSTRACT: Early statin treatment has beneficial effects on prognosis after acute coronary syndrome. The no-reflow phenomenon determines the prognosis after acute myocardial infarction. We investigated the effects of statin treatment before admission on the development of the no-reflow after infarction. We performed intracoronary myocardial contrast echocardiography in 293 consecutive patients with acute myocardial infarction undergoing successful primary percutaneous coronary intervention. There were no significant differences in the incidence of the no-reflow between the patients with and without hypercholesterolaemia. The 33 patients receiving chronic statin treatment before admission had lower incidence of the no-reflow than those without it (9.1 and 34.6%, P=0.003). They also showed better wall motion, smaller left ventricular dimensions, and better ejection fraction at 4.9+/-2.2 months later. Multivariable logistic regression analysis revealed that statin pre-treatment was a significant predictor of the no-reflow along with anterior wall infarction, ejection fraction on admission, and additional ST-elevation after reperfusion, whereas total cholesterol was not. Chronic pre-treatment with statins could preserve the microvascular integrity after acute myocardial infarction independent of lipid lowering, leading to better functional recovery.
    European Heart Journal 04/2006; 27(5):534-9. · 14.72 Impact Factor
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    ABSTRACT: Thrombolysis In Myocardial Infarction (TIMI) flow grade is widely used to evaluate myocardial tissue reperfusion in acute myocardial infarction (AMI), but the current grading system is incomplete. Therefore, we clarified the regulation of epicardial coronary flow velocity with the progression of microvascular dysfunction in AMI. We studied 36 patients with first anterior AMI. After intervention, we assessed TIMI flow grade and measured average peak velocity (APV) at baseline and after infusion of adenosine triphosphate (48 microg; baseline and hyperemic APVs, respectively) with a Doppler guidewire. We performed myocardial contrast echocardiography after 2 weeks to assess microvascular integrity (good reflow vs no reflow) and left ventriculography at admission and discharge (24 +/- 2 days) to measure regional wall motion (SD/chord). Patients were classified into 3 groups based on TIMI flow grade and microvascular integrity: TIMI grade 3 flow/good reflow (n = 16), TIMI grade 3 flow/no reflow (n = 12), and TIMI grade 2 flow (n = 8). Baseline APV was comparable in the patients with TIMI grade 3 flow but hyperemic APV was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow (hyperemic APV 59.3 +/- 25.8 vs 32.8 +/- 8.9 cm/s, p <0.01). All patients with TIMI grade 2 flow showed no reflow and the lowest values of baseline and hyperemic APVs. Regional wall motion at discharge was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow and TIMI grade 2 flow (-1.44 +/- 0.70, -2.69 +/- 0.31, and -2.88 +/- 0.48 SD/chord, respectively, p <0.01). In conclusion, compensatory reactive hyperemia preserves epicardial coronary flow velocity even in patients with microvascular damage, and with the progression of damage, this compensatory hyperemia can no longer preserve epicardial coronary flow velocity, and baseline APV is decreased in TIMI grade 2 flow.
    The American Journal of Cardiology 03/2006; 97(5):617-23. · 3.21 Impact Factor
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    ABSTRACT: In acute myocardial infarction, the coronary blood flow velocity waveform changes with the damage in the infarcted myocardium. We developed a grading system using the shorter diastolic deceleration time (DDT), appearance of systolic flow reversal (SFR), and disappearance of systolic anterograde flow. We studied 72 patients with a first anterior acute myocardial infarction. Doppler guidewire monitoring and myocardial contrast echocardiography were performed 10 and 15 minutes after percutaneous coronary intervention, and left ventriculography was performed at discharge (24 +/- 2 days) to measure regional wall motion (SD/chord). Patients were classified into 4 groups according to the coronary blood flow velocity pattern: group I (n = 39), DDT >or=600 ms; group II (n = 10), DDT <600 ms; group III (n = 17), DDT <600 ms with SFR; and group IV (n = 14), DDT <600 ms with SFR and without systolic anterograde flow. The no-reflow phenomenon was observed in no patients in group I, in 3 in group II, in 11 in group III, and all 14 patients in group IV. Regional wall motion was highest in group I and decreased with increasing group number (groups I, II, III, and IV, -1.45 +/- 0.80, -2.36 +/- 0.60, -2.90 +/- 0.50, and -3.20 +/- 0.52 SD/chord, respectively). With the progression of damage in the infarcted myocardium, the DDT shortened first, followed by the appearance of SFR, and then the disappearance of systolic anterograde flow. In conclusion, analysis of the coronary blood flow velocity pattern allows assessment of the severity of microvascular dysfunction and prediction of left ventricular functional outcomes.
    The American Journal of Cardiology 10/2005; 96(7):927-32. · 3.21 Impact Factor
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    ABSTRACT: We investigated whether embolic particles could be detected as high-intensity transient signals (HITS) with a Doppler guide wire during percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) We also assessed whether these signals could be reduced using a distal protection (DP) device. Embolization of thrombi and plaque components to the microcirculation is a major complication of PCI in patients with AMI. Embolic particles running in the cerebral artery are detected as HITS by transcranial Doppler ultrasound. We prospectively studied 16 consecutive patients with AMI who underwent direct PCI within 24 h after the onset of symptoms. A PercuSurge GuardWire (MedtronicAVE, Santa Rosa, California) was used as the DP device. Eight patients were randomly assigned to the non-DP group, and the remaining eight were assigned to the DP group. Coronary flow velocity was recorded continuously from before the first balloon inflation to after balloon deflation. All patients in the non-DP group had HITS detected (12 +/- 9 counts) within five consecutive beats (4 +/- 1 beat) after balloon deflation, but none were detected in any of the patients in the DP group. The Doppler guide wire can be used to visually detect and count emboli as HITS, and the DP device is effective for prevention of distal embolization.
    Journal of the American College of Cardiology 02/2005; 45(2):212-5. · 14.09 Impact Factor
  • Journal of Echocardiography. 01/2005; 3(1):33-39.
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    ABSTRACT: This case report describes the treatment of atrial fibrillation (AF) in a patient with Brugada syndrome. We found the triggers of AF in the superior vena cava during electrophysiological study and the isolation of superior vena cava with catheter ablation successfully eliminated the recurrence of AF. This case suggests that abnormal myocardial repolarization due to Na+-channel abnormality is not always the etiology of AF in patients with Brugada syndrome. In case of the focal trigger related to the initiation of AF, catheter ablation can be an effective therapeutic strategy.
    Journal of Arrhythmia 01/2005; 21(4):470-474.

Publication Stats

787 Citations
329.22 Total Impact Points

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Institutions

  • 2002–2014
    • Sakurabashi Watanabe Hospital
      Ōsaka, Ōsaka, Japan
  • 2012
    • Hyogo College of Medicine
      Nishinomiya, Hyōgo, Japan
  • 2010–2011
    • University Hospital Medical Information Network
      Edo, Tōkyō, Japan
  • 2004–2011
    • Osaka City University
      • Department of Cardiovascular Medicine
      Ōsaka, Ōsaka, Japan