Kuniyasu Harimoto
Memorial Hospital of South Bend
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The Cardiology | 2010
Hiroyasu Ueda; Nobuhiro Mitsusada; Kuniyasu Harimoto; Masami Miyawaki; Yuji Yasuga; Hisatoyo Hiraoka
Objectives: Diabetes mellitus is associated with the risk of restenosis and mortality after coronary stenting, but the relation between glycosylated hemoglobin (hemoglobin A1c) and prognosis has not yet been fully elucidated in patients with diabetes mellitus. The purpose of this study was to evaluate whether hemoglobin A1c is associated with a risk of major adverse cardiac events (MACE) after successful drug-eluting stent (DES) implantation in patients with diabetes mellitus. Methods: In a retrospective study with a prospective follow-up, 206 patients with diabetes mellitus undergoing successful DES implantation were enrolled in this study. Hemoglobin A1c levels were measured within 1 month before coronary stenting. Results: During a period of 4,811 person-months, we confirmed 40 cases of MACE. Higher hemoglobin A1c levels increased the incidence of MACE. Based on multivariate analysis, hemoglobin A1c was a significant predictor of MACE. The multiple-adjusted hazard ratio for a 1% increase in hemoglobin A1c levels was 1.40 (95% CI: 1.13–1.74, p = 0.002) for MACE after adjustment for age, gender, ejection fraction, chronic renal failure on hemodialysis, and statins. Conclusions: Hemoglobin A1c is associated with an increased risk of MACE after successful DES implantation in patients with diabetes mellitus.
European Journal of Echocardiography | 2013
Tatsuya Kawasaki; Michiyo Yamano; Chieko Sakai; Kuniyasu Harimoto; Shigeyuki Miki; Tadaaki Kamitani; Hiroki Sugihara
AIMS Hypertrophic cardiomyopathy (HCM) patients often develop left--ventricular subendocardial ischaemia, a cause of chest symptoms, despite normal epicardial coronary arteries. The aim of this study was to examine whether ultrasonic tissue characterization or late gadolinium enhancement on cardiac magnetic resonance imaging can detect subendocardial ischaemia in patients with HCM. METHODS AND RESULTS Subendocardial ischaemia was quantified on exercise Tc-99m tetrofosmin myocardial scintigraphy in 29 non-obstructive HCM patients with asymmetric septal hypertrophy. Ultrasonic tissue characterization using cyclic variation of integrated backscatter (CV-IB) and late gadolinium enhancement on cardiac magnetic resonance imaging were analysed separately in the right halves and the left halves of the ventricular septum in relation to subendocardial ischaemia. Subendocardial ischaemia was identified in 17 (59%) patients. The ratio of CV-IB in the right-to-left halves of the ventricular septum was significantly higher in patients with subendocardial ischaemia (1.19 ± 0.10) than those without (0.84 ± 0.10, P = 0.04). The optimal cutoff for the detection of subendocardial ischaemia was the ratio of CV-IB >1.0, with a sensitivity of 80%, specificity of 71%, and accuracy of 76%. On the other hand, late gadolinium enhancement was not associated with subendocardial ischaemia in our cohort. CONCLUSION Ultrasonic tissue characterization using CV-IB separately in the right and left halves of the ventricular septum, but not late gadolinium enhancement on magnetic resonance imaging, provided useful information in detecting subendocardial ischaemia in patients with HCM. Ultrasonic tissue characterization may be useful in selecting patients who will benefit from medications to relieve chest symptoms.
Circulation | 2015
Tatsuya Kawasaki; Kuniyasu Harimoto; Sakiko Honda; Yoshimi Sato; Michiyo Yamano; Shigeyuki Miki; Tadaaki Kamitani
BACKGROUND Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial fibrosis in association with adverse cardiovascular events. Electrocardiography (ECG) could provide helpful information on myocardial fibrosis in HCM, as in coronary artery disease. METHODS AND RESULTS A total of 60 patients with HCM without bundle branch block underwent cardiac magnetic resonance imaging (CMR). The extent or location of late gadolinium enhancement (LGE) was examined in relation to 12-lead ECG. A notch on QRS was defined as at least 2 consecutive spikes in the same polarity with a reversal of direction ≥90° and the initial negative deflection ≥0.05 mV. LGE was associated with notched QRS, leftward QRS axis, and prolonged QRS duration, but not with any other findings such as abnormal Q waves, R-wave amplitude, or ST-T changes. Notched QRS was most useful in determining the presence or absence of myocardial fibrosis, with a sensitivity of 70% and a specificity of 81% using a cut-off of the number of leads with notched QRS ≥2. The number of notched QRS leads was positively correlated with LGE volume (P<0.01) and the lead distribution of notched QRS was informative about the location of LGE. CONCLUSIONS A notch on QRS was useful in estimating myocardial fibrosis as assessed on CMR LGE in HCM patients without bundle branch block.
The Cardiology | 2012
Tatsuya Kawasaki; Chieko Sakai; Kuniyasu Harimoto; Michiyo Yamano; Shigeyuki Miki; Tadaaki Kamitani; Hiroki Sugihara
Objectives: Limited data are available regarding Holter monitoring for cardiovascular events except for ventricular tachycardia as a risk marker for sudden death in hypertrophic cardiomyopathy (HCM). We aimed to examine Holter findings in relation to the long-term prognosis in patients with HCM. Methods: Ambulatory Holter monitoring was performed in 106 HCM patients with sinus rhythm. All were prospectively followed for the composite endpoint of sudden death, cardiovascular death, and hospitalization for heart failure or stroke associated with atrial fibrillation. Results: Cardiovascular events occurred in 19 patients during a mean follow-up of 10.1 years. Neither arrhythmia information nor autonomic information as assessed by heart rate variability and turbulence significantly differed between HCM patients with and without cardiovascular events. Average heart rates were lower in HCM patients with cardiovascular events (64.7 ± 11.2 beats/min) than in those without (73.7 ± 10.2 beats/min, p = 0.001). Multivariate Cox proportional hazards regression analysis after adjustment for baseline characteristics showed that lower average heart rate remained an independent predictor of cardiovascular events (HR: 0.47 per 10 increase; 95% CI: 0.25–0.87; p = 0.016). Conclusion: Average heart rate on Holter monitoring predicted long-term prognosis in our cohort. Further multicenter studies are needed to confirm our results.
Journal of Electrocardiology | 2014
Kuniyasu Harimoto; Tatsuya Kawasaki; Sakiko Honda; Shigeyuki Miki; Tadaaki Kamitani
BACKGROUND Right bundle branch block (RBBB) is associated with ventricular septal fibrosis in patients with hypertrophic cardiomyopathy (HCM) after alcohol septal ablation, but little data are available in HCM patients without a history of septal ablation. METHODS Magnetic resonance late gadolinium enhancement (LGE) was performed in 59 HCM patients with no history of alcohol septal ablation. The location and extent of LGE were examined in relation to electrocardiographic features including RBBB. RESULTS LGE volume was higher in 7 HCM patients with RBBB (7.3±7.4g/cm) than in patients without RBBB (2.9±7.4g/cm, p=0.016). LGE volume was positively correlated to QRS duration of RBBB (correlation coefficient=0.93, p=0.023). The diagnostic value of RBBB was highly specific for the detection of LGE in the ventricular septum, with sensitivity 21% and specificity 94%. CONCLUSIONS The presence of RBBB may be a simple marker for detecting ventricular septal fibrosis in HCM patients who had no history of alcohol septal ablation. Further studies are necessary to confirm our findings.
Journal of Cardiology Cases | 2012
Asumi Matsumoto; Tatsuya Kawasaki; Mayumi Takeoka; Michiyo Yamano; Chieko Sakai; Kuniyasu Harimoto; Shigeyuki Miki; Tadaaki Kamitani
Pulmonary artery dissection is an extremely rare and fatal disease that is difficult to diagnose. We report a case of a 97-year-old woman with heart failure, who was diagnosed as having silent pulmonary artery dissection by chance during transthoracic echocardiography. Surgical treatment for pulmonary artery dissection was not performed, but the patient has been doing well in a sanatorium for more than 2 years, being a centenarian.
Journal of Cardiology Cases | 2013
Kuniyasu Harimoto; Tatsuya Kawasaki; Hiroyuki Sakai; Hiroaki Murata; Chieko Sakai; Michiyo Yamano; Shigeyuki Miki; Tadaaki Kamitani
Chordoma is a rare neoplasm of bone that develops from the remnants of the primitive notochord. We present a 78-year-old woman with metastatic chordoma to the left ventricle. She had been diagnosed with sacral chordoma 5 years earlier, and chordoma gradually spread to numerous muscles, the ankle joint of the left leg, bilateral lungs, and the brain, despite repeated surgical excisions and carbon heavy-ion radiotherapy. Positron emission tomography/computed tomography showed an abnormal accumulation in the heart, with features similar to the other metastatic lesions. Transthoracic echocardiography could not provide a clear view of the heart, but multidetector computed tomography revealed that a giant abnormal mass was attached to the apical inferior segment of the left ventricle. The patient stated that she did not want to undergo surgical resection for the cardiac mass. The chordoma has been slowly increasing in size, but she has remained asymptomatic without cardiovascular events for more than a year since the diagnosis of cardiac metastasis. <Learning objective: Multidetector computed tomography provided information not only about the structure morphology of the left ventricular mass, but also about the pathological features using the attenuation values of computed tomography, enabling us to make a diagnosis of a metastatic lesion to the left ventricle from sacral chordoma.>.
Circulation | 2017
Yoshimi Sato; Tatsuya Kawasaki; Sakiko Honda; Kuniyasu Harimoto; Shigeyuki Miki; Tadaaki Kamitani; Hirokazu Shiraishi; Satoaki Matoba
BACKGROUND The 4th heart sound (S4) is commonly heard in patients with hypertrophic cardiomyopathy (HCM). The 3rd heart sound (S3) is also audible in HCM patients regardless of the presence or absence of heart failure. These extra heart sounds may be associated with myocardial fibrosis because myocardial fibrosis has been suggested to affect left ventricular compliance.Methods and Results:The present retrospective study evaluated 53 consecutive HCM patients with sinus rhythm who had no symptoms of heart failure and underwent an initial assessment including phonocardiography, echocardiography, and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI). S3 was detected on phonocardiography in 13% of all patients, and S4 was recorded in 75% of patients. Patients with S3 had a higher incidence of LGE and larger LGE volumes (86% and 11.5±2.4 g/cm, respectively) than patients without S3 (33% and 2.5±0.8 g/cm, respectively; P=0.02 and P=0.002). The presence of S4 was not associated with MRI findings, including the incidence of LGE and LGE volume. The diagnostic value of S3 for the detection of LGE was highly specific (97%), with a low sensitivity (29%). CONCLUSIONS Myocardial fibrosis, as assessed by LGE, was associated with S3 but not with S4 in patients with HCM. These results may contribute to the risk stratification of patients with HCM.
Journal of Medical Ultrasonics | 2016
Yoshimi Sato; Tatsuya Kawasaki; Michiyo Yamano; Sakiko Honda; Kuniyasu Harimoto; Shigeyuki Miki; Tadaaki Kamitani; Satoaki Matoba
Aneurysms of the sinus of Valsalva are characterized by dilatation of at least one of the three aortic sinuses. We experienced a case with unruptured aneurysm of the right sinus of Valsalva, in which serial imaging studies were useful in assessing a rare complication after surgical repair. An asymptomatic 75-year-old man underwent patch closure of the aneurysm orifice because of progressive enlargement of the aneurysm. The postoperative course was uneventful, and computed tomography (CT), performed a week after the patch repair, showed no leakage of contrast medium into the isolated aneurysm. Three months later, echocardiography showed decreased size of the aneurysm with heterogeneous echogenicity and possible blood flow in the aneurysm, findings suggestive of thrombus formation and a recurrent fistula. CT with contrast medium showed partial recanalization between the patched aneurysm and the right sinus of Valsalva. Follow-up echocardiography, performed 1 year after surgery, revealed neither definite aneurysm nor shunt flow of Valsalva. The present case highlights that non-invasive follow-up can be an alternative option when carried out with caution in selected patients with incomplete closure of Valsalva aneurysm.
Journal of Cardiology Cases | 2013
Chieko Sakai; Tatsuya Kawasaki; Kuniyasu Harimoto; Michiyo Yamano; Shigeyuki Miki; Tadaaki Kamitani
Ventricular septal defect is a common congenital heart disease for which patch closure technique using cardiopulmonary bypass has been applied for a few decades, resulting in a low incidence of perioperative complications. We report a 26-year-old woman with bradycardia of 25-30 beats per minute, which was considered to be a late-onset complication of surgical closure of an isolated ventricular septal defect performed 21 years earlier. She has been stable for more than 9 months without an implanted pacemaker, although her heart rate was always around 40 beats per minute in scheduled follow-up visits. <Learning objective: We experienced a 26-year-old woman with bradycardia of 25-30 beats per minute, which was considered to be a late-onset complication of surgical closure of an isolated ventricular septal defect performed 21 years earlier. Our case highlights the importance of close follow-up for patients who underwent successful surgical closure of a ventricular septal defect and have shown nonsignificant bradycardia, even though they have no symptoms.>.