Motomaru Masutani

Hyogo College of Medicine, Nishinomiya, Hyōgo, Japan

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Publications (46)163.07 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: We reported a case of 78-year-old male who had a severe stenosis in the right coronary artery (RCA) and an intermediate stenosis in the left anterior descending artery (LAD) without visible collateral flow to the RCA on angiogram. Fractional flow reserve (FFR) in the LAD lesion, which revealed significant value as 0.70, increased to 0.78 after revascularization of the RCA lesion. The FFR in an intermediate stenosis should be performed after PCI for severe stenosis in the other coronary arteries. Otherwise, the severity of the stenosis could be overestimated due to the presence of invisible collateral circulation.
    Cardiovascular Intervention and Therapeutics 06/2014; DOI:10.1007/s12928-014-0275-3
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    ABSTRACT: Background: Although previous intravascular ultrasound (IVUS) studies reported that the drug-eluting stent (DES) has successfully decreased in-stent restenosis (ISR) by inhibiting neointimal hyperplasia (NIH) in the coronary artery lesion, no IVUS data for vascular response after DES implantation in the superficial femoral artery (SFA) have been published. Methods and Results: We retrospectively analyzed 38 de novo SFA lesions from 32 patients who underwent endovascular therapy (EVT) with self-expanding bare-metal nitinol stent (25 lesions; BMS group) or self-expanding paclitaxel-eluting nitinol stents (13 lesions; PES group). At 6 months after EVT, follow-up IVUS was done to evaluate NIH. Serial IVUS volumetric analysis was done after stent deployment and at follow-up. Mean stent, lumen and neointimal areas were calculated as the volume divided by the stent length. The primary endpoint of this study was mean late lumen loss at 6-month follow-up. The mean follow-up period was 189±39 days. Mean neointimal area was smaller in the PES group compared to the BMS group (3.3±1.0mm(2) vs. 10.2±4.1mm(2), P<0.001). Mean late lumen loss was significantly lower in the PES group compared to the BMS group (-2.3±3.7mm(2) vs. 2.1±4.7mm(2), P<0.05). Conclusions: EVT with DES in SFA lesions might decrease NIH associated with ISR in short-term follow-up.
    Circulation Journal 04/2014; 78(6). DOI:10.1253/circj.CJ-13-1508 · 3.69 Impact Factor
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    ABSTRACT: The frequency of radial artery occlusion was compared between patients receiving 4Fr versus 6Fr transradial coronary interventions (TRIs) in an open-label randomized trial ( identifier: NCT00815997). The primary outcome measure was radial artery occlusion on the day after TRI. The secondary outcome measures were the procedural success, major advanced cardiac events, access site-related complications, procedural times, fluoroscopy times, and contrast dye usage. A total of 160 patients were included. The procedure was successful in 79 of 80 patients (99%) in both groups. Whereas the 4Fr group showed no access site-related complications, the 6Fr developed 5 (6%), including 3 radial artery occlusions and 2 bleedings (1 radial artery perforation and 1 massive hematoma; p = 0.02). Although the radial artery occlusion rate was lower in the 4Fr versus the 6Fr groups, the difference was not significant (0% vs 4%, p = 0.08). The mean hemostasis time was significantly shorter in the 4Fr than in the 6Fr groups (237 ± 105 vs 320 ± 238 minutes, p = 0.007). In conclusion, these findings suggest that 4Fr TRI may become a less invasive alternative to 6Fr TRI in treating coronary artery diseases.
    The American journal of cardiology 04/2014; 113(12). DOI:10.1016/j.amjcard.2014.03.040 · 3.58 Impact Factor
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    ABSTRACT: Despite a sufficient coronary blood flow after primary percutaneous coronary intervention for patients with ST-segment-elevation myocardial infarction; some patients have a poor outcome because of microcirculatory damage. This study evaluates whether the thermodilution-derived coronary blood flow parameters immediately after primary percutaneous coronary intervention predict early microvascular damage and midterm outcomes in patients with ST-segment-elevation myocardial infarction. Using a pressure sensor/thermistor-tipped guidewire, we measured the index of microcirculatory resistance at maximum hyperemia, and coronary blood flow pattern was assessed from the thermodilution curves after successful primary percutaneous coronary intervention in 88 patients with ST-segment-elevation myocardial infarction. Coronary blood flow pattern was classified into 3 groups according to the shape of thermodilution curve: a narrow unimodal (n=41), a wide unimodal (n=32), or bimodal (n=15). All patients had contrast-enhanced cardiac magnetic resonance scans within 2 weeks. The index of microcirculatory resistance values were significantly higher both in a wide unimodal and in a bimodal groups than in a narrow unimodal group (65±41 and 76±38 versus 20±9U; P<0.001). Bimodal group had higher prevalence of microvascular obstruction on contrast-enhanced cardiac magnetic resonance when compared with the other groups (100%, 78%, and 30%; P<0.001). Patients in bimodal group had a higher risk of death and heart failure rehospitalization at 6 months (73%, 6.3%, 7.3%; P<0.001). Multivariate analysis revealed that bimodal shape of the thermodilution curve was the only independent predictor of cardiac death at 6 months after ST-segment-elevation myocardial infarction (P<0.01). A bimodal shape of the thermodilution curve, which may indicate myocardial edema and consequent extrinsic compression of the capillary network, is associated with microcirculatory damage and poor midterm clinical outcomes rather than index of microcirculatory resistance value itself.
    Circulation Cardiovascular Interventions 02/2014; 7(3). DOI:10.1161/CIRCINTERVENTIONS.113.000505 · 6.54 Impact Factor
  • Journal of Cardiology Cases 12/2013; 8(6):190–192. DOI:10.1016/j.jccase.2013.08.008
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    ABSTRACT: Background: Previous intravascular ultrasound (IVUS) studies have reported that a tiny reference cross-sectional area (CSA), stent under-expansion, stent asymmetry, stent edge dissection, and tissue protrusion are associated with target lesion revascularization (TLR) after coronary intervention. In the lower limb, however, it has not been reported that these findings correlate with TLR after endovascular therapy (EVT). Methods and Results: A total of 236 consecutive superficial femoral artery (SFA) lesions in patients who underwent IVUS after self-expanding nitinol stent implantation, were analyzed. Stent expansion ratio was calculated as minimum stent CSA/reference lumen CSA, radial stent symmetry index as minimum/maximum stent diameter, and axial stent symmetry index as minimum/maximum stent CSA. TLR was defined as clinically driven revascularization with ≥75% restenosis of the target lesion. The mean follow-up period was 34±15 months. TLR were performed in 42 lesions (17.8%). There were no significant differences in stent expansion ratio, stent symmetry indices, and tissue protrusion between the TLR and no-TLR groups. Multivariate analysis indicated that total stent length (odds ratio [OR], 1.004; P<0.05), distal reference CSA (OR, 0.91; P<0.01), and stent edge dissection (OR, 3.51; P<0.01) were independent predictors of TLR. Conclusions: Stent implantation in tiny vessels and stent edge dissection in SFA lesions are indicators of high risk of TLR. Post-procedural stent under-expansion and stent asymmetry, however, were not associated with TLR.
    Circulation Journal 03/2013; 77(6). DOI:10.1253/circj.CJ-12-1182 · 3.69 Impact Factor
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    ABSTRACT: Aims: The main cause of acute myocardial infarction (AMI) is the disruption of a thin-cap fibroatheroma (TCFA) and subsequent thrombosis. Mortality increases in diabetic patients due to cardiovascular events; there may be differences in the vulnerable plaques between diabetic and non-diabetic patients. We used optical coherence tomography (OCT) to assess the incidence of vulnerable plaques in diabetic patients with AMI. Methods and results: OCT was performed in all three major coronary arteries of 70 AMI patients: 48 non-diabetic and 22 diabetic patients. The OCT criterion for TCFA was the presence of both a lipid-rich plaque composition and a fibrotic cap thickness of <65 µm. A ruptured plaque contains a cavity in contact with a lumen and a residual fibrous cap. OCT identified 68 plaque ruptures (1.0 per patient; range, 0-3) and 162 TCFAs (2.3 per patient; range, 0-5). The incidences of plaque rupture and TCFA at culprit lesions were similar. However, non-culprit-lesion TCFAs were observed more frequently in diabetic patients than in non-diabetic patients. Conclusions: Although the prevalence of vulnerable plaque in culprit lesions was similar between diabetic and non-diabetic patients, vulnerable plaques were observed in non-culprit lesions more in diabetic patients than in non-diabetic patients.
    EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 12/2012; 8(8):955-61. DOI:10.4244/EIJV8I8A145 · 3.17 Impact Factor
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    ABSTRACT: Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute myocardial ischemia and is associated with various pathophysiologies, such as pregnancy, postpartum, and collagen diseases. It is frequently fatal and most cases are diagnosed at autopsy. Therefore, the early diagnosis of SCAD and initiation of treatment may be life saving. In this report, we describe a case of SCAD of right coronary artery, possibly triggered by transient high blood pressure, with no apparent atherosclerotic involvement detected by intravascular ultrasound (IVUS) and successfully treated with stent implantation. The IVUS helped us to confirm the diagnosis, navigate the guidewire into the true lumen, and understand the mechanism for the appearance of a lotus root formation.
    Journal of Cardiology Cases 09/2012; 6(3):e78-e80. DOI:10.1016/j.jccase.2012.05.007
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    ABSTRACT: Carbon dioxide (CO(2)) has been used as an arterial contrast agent for high-risk patients who were allergic to iodinated contrast material and for those with chronic kidney disease (CKD). The feasibility, safety, imaging quality and therapeutic role of CO(2) angiography in the endovascular therapy (EVT) for patients with CKD was evaluated. EVT was performed in 107 consecutive patients with iliofemoral artery disease (148 limbs; mean age, 73±9 years) who were admitted to our hospital from January 2010 to April 2011. Intravascular ultrasound (IVUS)-guided EVT with CO(2) was applied for the treatment of 50 patients (70 limbs) with CKD (group 1). IVUS-guided EVT with iodinated contrast media was applied for the treatment of 57 patients (78 limbs) without CKD (group 2). CO(2) was injected by hand using a simple homemade delivery system. The overall technical success was 100% in both groups without any major complication. Preprocedure and postprocedure ankle-brachial indices significantly improved in the both groups (0.93±0.11 vs. 0.59±0.19, P<0.01; 0.95±0.13 vs. 0.62±0.22, P<0.01, respectively). All of the CO(2) arteriograms were good or acceptable imaging quality if assessed by 2 independent observers. CO(2) arteriograms, using an inexpensive simple homemade delivery system, are feasible and safe in patients with CKD in the evaluation and for EVT of iliofemoral artery disease.
    Circulation Journal 04/2012; 76(7):1722-8. DOI:10.1253/circj.CJ-11-1382 · 3.69 Impact Factor
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    ABSTRACT: Previous studies described that inadequate tissue perfusion after primary angioplasty in ST-elevation myocardial infarction (STEMI) patients is associated with adverse cardiac events. This study evaluated whether plaque morphological intravascular ultrasound (IVUS) characteristics affects tissue perfusion after stent implantation in STEMI patients. A total of consecutive 306 STEMI patients who underwent primary angioplasty with IVUS were analyzed. Maximum ST-segment elevation before angioplasty was compared with ST-segment levels 60min after angioplasty. Percent ST-segment resolution (STR) was calculated and categorized as complete (>70%), partial (30-70%), and absent (<30%). Qualitative and quantitative IVUS analyses were performed using standard methods. Plaque with ultrasound attenuation was defined as IVUS finding with backward signal attenuation behind plaque >180° without dense calcium. One-hundred-fifty patients had complete, 101 had partial, and 55 had absent STR. The incidence of in-hospital death tended to be higher in absent STR than in partial and complete STR groups. Multivariate analysis indicated that remodeling index (P=0.004), the presence of ultrasound attenuation (P=0.02), percentage stent expansion (P=0.03), and the presence of deep calcium (P=0.049) were the independent predictors related to the occurrence of absent STR after angioplasty. Positive vessel remodeling, plaque with ultrasound attenuation >180°, deep calcium, and stent overexpansion as assessed by IVUS are associated with the absence of STR after primary angioplasty in patients with STEMI.
    Circulation Journal 08/2011; 75(11):2642-7. DOI:10.1253/circj.CJ-11-0011 · 3.69 Impact Factor
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    ABSTRACT: This study evaluated the effect of pravastatin pre-treatment on post-procedural index of microcirculatory resistance (IMR) values that are introduced for assessing the status of the microcirculation independently of the epicardial area. Pre-treatment with statins decreased the incidence of cardiac enzyme increase after percutaneous coronary intervention (PCI). However, 2 different etiologies, distal embolization of atheroma or ischemia caused by side-branch occlusion, cannot be differentiated by measuring cardiac enzyme levels. Eighty patients with stable angina were randomly assigned to either pravastatin treatment (20 mg/day, n = 40) or no treatment (n = 40) 4 weeks before elective PCI. An intracoronary pressure/temperature sensor-tipped guidewire was used. Thermodilution curves were obtained during maximal hyperemia. The IMR was calculated from the ratio of the mean distal coronary pressure at maximal hyperemia to the inverse of mean hyperemic transit time. Creatine kinase-myocardial band and troponin I values were measured at baseline and at 8 and 24 h after PCI. Post-PCI troponin I levels tended to be lower in patients with pravastatin treatment (median: 0.13 [interquartile range (IQR): 0.10 to 0.31] vs. 0.22 [IQR: 0.10 to 0.74] ng/ml, p = 0.1). However, patients with pravastatin treatment had significantly lower IMR than did patients without pravastatin treatment (median: 12.6 [IQR: 8.8 to 18.0] vs. 17.6 [IQR: 9.7 to 33.9], p = 0.007). Multivariate analysis revealed that the lack of pravastatin pre-treatment was the only independent predictor of post-PCI impaired IMR (p = 0.03). Post-PCI measurement of the IMR confirmed that pre-treatment with pravastatin was associated with reduced microvascular dysfunction induced by PCI regardless of side branch occlusions. These data suggest that pre-treatment with statin is desired in patients undergoing elective PCI. (The Impact of Pravastatin Pretreatment on Periprocedural Microcirculatory Damage After Percutaneous Coronary Intervention; UMIN000002885).
    JACC. Cardiovascular Interventions 05/2011; 4(5):513-20. DOI:10.1016/j.jcin.2011.02.005 · 7.40 Impact Factor
  • Nihon Naika Gakkai Zasshi 04/2011; 100(4):1008-29.
  • Motomaru Masutani
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    ABSTRACT: Currently the 0.014-inch guidewire is commonly used for coronary intervention and all devices are 0.014 inch-compatible. The size of common guiding catheters is 6Fr. However, PCI requires oral administration of dual antiplatelet agents, and punctured-site complications such as hemorrhage and hematoma occur more frequently with use of a 6Fr guiding catheter compared to a 5Fr guiding catheter. Moreover, 6Fr or larger guiding catheters may cause radial arterial occlusion, although the transradial approach causes less punctured-site complications compared to the transfemoral approach. Recently, 0.010-inch guidewires applicable for the kissing balloon technique (KBT) using a 5Fr guiding catheter and 0.010-inch guidewire-compatible balloons have been developed in Japan, and a 3Fr angiography catheter has also been developed. We refer to these devices as the "slender system", and we have used this system for active treatment of bifurcation lesions and chronic total occlusion (CTO). In this report, we describe angiography using a 3Fr catheter, the KBT using a 5Fr guiding catheter and 0.010-inch guidewires, and treatment of CTO using a 5Fr catheter and 0.010-inch guidewires. For CTO treated using the slender system at our facility, the transradial arterial approach was used in 90.7% of cases, treatment using the slender system alone succeeded in 65.1%, and the overall success rate was 89.5%. Therefore, our results show that complex lesions may be treatable using the slender system, and that not all complex lesions require a 6Fr or larger guiding catheters, a femoral arterial approach, or bilateral guiding catheters.
    Nippon rinsho. Japanese journal of clinical medicine 02/2011; 69(2):287-94.
  • Nihon Naika Gakkai Zasshi 01/2011; 100(4):1008-1029. DOI:10.2169/naika.100.1008
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    ABSTRACT: Zotarolimus-eluting stents (ZES) have a higher rate of neointimal coverage than the first-generation drug-eluting stents on optical coherence tomography (OCT). To determine whether neointimal coverage of stent struts detected by OCT can be used as a surrogate for endothelial function after ZES implantation. Cross-sectional observational study. Three months after ZES implantation. OCT was performed in 20 patients with a ZES at 3 months after stent implantation to evaluate strut coverage. Endothelium-dependent coronary vasomotion was estimated by infusing incremental doses of acetylcholine into the coronary ostium. The vascular response was measured in the 10&emsp14;mm segments proximal and distal to the stent. Of 20 ZES, 15 (75%) were covered completely with neointima, but the remaining 5 ZES had exposed struts. The high-dose acetylcholine infusion produced significant vasoconstriction in the proximal (-9.8±10.1%) and the distal stent segment (-29.7±22.7%). However, the degree of vasoconstriction to acetylcholine varied between individuals (from -0.6% to -77%). Although no relationship was observed between coronary vasomotor response (percentage change in diameter after acetylcholine administration) and average neointimal thickness, the number of cross-sections with uncovered struts showed an inverse correlation with coronary vasomotor response in proximal and distal stent segments (r=-0.57, p=0.007 and r=-0.83, p<0.001, respectively). The existence of exposed struts was associated with abnormal vasoconstriction to acetylcholine at 3 months after ZES implantation. The findings suggest that complete neointimal coverage of stent struts assessed by OCT could be used as a surrogate for vasomotion impairment at 3 months after ZES implantation.
    Heart (British Cardiac Society) 12/2010; 97(12):977-82. DOI:10.1136/hrt.2010.204594 · 6.02 Impact Factor
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    ABSTRACT: Generally, both the preprocedural evaluation and endovascular therapy (EVT) for lower limb arteries require contrast media that is harmful for patients with chronic renal insufficiency. In the present study these procedures were performed without using nephrotoxic contrast media in patients with preexisting renal insufficiency and iliofemoral artery disease. The 36 consecutive patients with chronic renal insufficiency underwent preprocedural evaluation with duplex examination, magnetic resonance angiography (MRA) without contrast media, and plain computed tomography (CT). A total of 51 lesions were treated using intravascular ultrasound (IVUS) without contrast media. The overall technical success was 100% without any complications. Pre- and postprocedural ankle-brachial indices changed from 0.59 ± 0.23 to 0.92 ± 0.14. The mean serum creatinine concentration before and after treatment, and 3 months after treatment did not change (2.1 ± 1.4, 2.0 ± 1.4, and 2.1 ± 1.6 mg/dl, respectively). The overall 3-month survival rate and limb salvage rate was 100%. EVT comprising duplex, MRA, and CT for preprocedural evaluation and IVUS-guided procedure is feasible and may avoid intra-arterial contrast injection in selected patients deemed at high risk for renal failure from nephrotoxic contrast material.
    Circulation Journal 12/2010; 75(1):179-84. DOI:10.1253/circj.CJ-10-0438 · 3.69 Impact Factor
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    ABSTRACT: Although there is a discussion on the outcome between percutaneous coronary intervention (PCI) and bypass surgery, PCI is clearly superior to bypass surgery in terms of less invasiveness. One of the further less invasive strategy is transradial approach (TRI). There have been several limitations such as low backup force of guiding catheters. However, mechanics studies showed that the backup force does not relate to approach site but to catheter shape and size. The other strategy is slender PCI using a 5 Fr or less guiding catheter. The slender PCI has also several limitations, however, some of these limitations have been overcome using new slender devices and new slender specific techniques. In this article, current progress in this field using new devices is reviewed. The less invasive strategy such as TRI and slender PCI may be the future direction of PCI because they prevent complications and improve quality of life.
    07/2010; 25(2):60-64. DOI:10.1007/s12928-010-0023-2
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    ABSTRACT: The aim of this study was to evaluate the safety and effectiveness of a 0.010-inch guidewire and a balloon catheter for treatment of chronic total occlusion (CTO). Pathological studies have shown that 60-70% of CTO lesions have microchannels of sizes equal to or less than 0.010 inch. The PIKACHU registry is a prospective, multicenter registry study. A 0.010-inch guidewire had to be used as the first guidewire to attempt to pass the CTO lesion. The primary endpoint was device success using a 0.010 system. A total of 141 patients with 141 lesions were enrolled. The median duration of occlusion was 9 months (range 3-156). Average guiding catheter size was 5.8 +/- 0.7 Fr. and TRI was 76.6 %. CTOs were mostly between 10-20 mm long, observed in 53 occlusions. There were 107 lesions (75.9%) with bending of more than 45 degrees. Calcification was seen in 91 lesions (64.5%). A 0.010-inch guidewire was successfully passed through in 97 of 141 lesions (68.8%). A 0.010-inch guidewire compatible balloon catheter was passed in 87 of the 97 lesions (88.7%) and final PCI success was achieved in all the cases. The overall clinical success rate was 87.9% (124/141). No MACE or bleeding complications were observed. The PIKACHU registry data suggest that the 0.010-inch system is safe and practicable for treatment of CTO lesions.
    Catheterization and Cardiovascular Interventions 06/2010; 75(7):1006-12. DOI:10.1002/ccd.22434 · 2.51 Impact Factor
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    ABSTRACT: We evaluated the geographic distribution of thin-cap fibroatheromas (TCFAs) in the coronary arteries using optical coherence tomography (OCT), a high-resolution imaging modality. Plaque rupture is the most frequent cause of acute myocardial infarction (AMI). It has been recognized that TCFA is the primary plaque type at the site of plaque rupture. We performed 3-vessel OCT examinations in 55 patients: 35 AMI and 20 stable angina pectoris patients. The criteria for TCFA in an OCT image was a lipid-rich plaque with fibrotic cap thickness <65 microm. The distance between each TCFA location and the respective coronary artery ostium was measured with motorized OCT imaging pullback. The total length of all 3 coronary arteries imaged by OCT pullbacks was 82 +/- 21 mm in the left anterior descending coronary artery (LAD), 67 +/- 26 mm in the left circumflex coronary artery (LCx), and 104 +/- 32 mm in the right coronary artery (RCA). OCT detected 94 TCFAs in 165 coronary arteries. The minimum fibrous-cap thickness of TCFAs was 57.4 +/- 5.4 microm in AMI patients, and 55.9 +/- 7.3 microm in stable angina pectoris patients (p = 0.4). Of the total of 94 TCFAs, 28 were detected in the LAD, 18 in the LCx, and 48 in the RCA. Most LAD TCFAs were located between 0 and 30 mm from the LAD ostium (76%). Conversely, LCx and RCA TCFAs were evenly distributed throughout the entire coronary length. The clustering of the TCFAs was similar in culprit segments as compared with nonculprit segments. In AMI patients, most LAD TCFAs were distributed near side branches, mainly positioned opposite the side branch bifurcation. Three-vessel OCT imaging showed that TCFAs tend to cluster in predictable spots within the proximal segment of the LAD, but develop relatively evenly in the LCx and RCA arteries.
    JACC. Cardiovascular imaging 02/2010; 3(2):168-75. DOI:10.1016/j.jcmg.2009.11.004 · 14.29 Impact Factor
  • EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 09/2009; 5(4):515-7. DOI:10.4244/EIJV5I4A82 · 3.76 Impact Factor