Masaru Sawazaki
Nagoya University
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Featured researches published by Masaru Sawazaki.
Annals of Surgery | 1998
Kenzo Yasuura; Hiroshi Okamoto; Shin Morita; Yutaka Ogawa; Masaru Sawazaki; Akira Seki; Hiroshi Masumoto; Akio Matsuura; Takashi Maseki; Shuhei Torii
OBJECTIVE Our experience with omental flap transposition in the treatment of deep sternal wound infections is reviewed here with an emphasis on efficacy, risk factors for in-hospital mortality rates, and long-term results. SUMMARY BACKGROUND DATA Even with improvements in muscle and omental flap transposition, the timing of closure and the surgical strategy are controversial. METHODS Forty-four consecutive patients with deep sternal wound infections were treated using the omental flap transposition from 1985 through 1994. The strategies included debridement with delayed omental flap transposition or single-stage management, which consisted of debridement of the sternal wound and omental flap transposition. Methicillin-resistant Staphylococcus aureus was cultured from more than 50% of the wounds. A logistic regression analysis was used to identify the predictors of in-hospital death after omental flap transposition. RESULTS There were seven (16%) in-hospital deaths. Univariate analysis demonstrated that hemodialysis and ventilatory support at the time of omental flap transposition were significantly associated with in-hospital mortality rates (p = 0.0023 and p = 0.0075, respectively). Thirty-seven patients whose wounds healed well were discharged from the hospital. Two patients with cultures positive for methicillin-resistant Staphylococcus aureus had recurrent sternal infections. Patients without positive methicillin-resistant Staphylococcus aureus cultures had good long-term results after reconstructive surgery. CONCLUSIONS Transposition of an omental flap is a reliable option in the treatment of deep sternal wound infections, unless the patients require ventilatory support or hemodialysis at the time of transposition.
The Annals of Thoracic Surgery | 1995
Toshiaki Itoh; Hiroshi Okamoto; Takao Nimi; Shin Morita; Masaru Sawazaki; Yutaka Ogawa; Teiji Asakura; Kenzo Yasuura; Toshio Abe; Mitsuya Murase
BACKGROUND This study examined whether the atrial fibrillation that commonly occurs in patients with a mitral valve operation could be eliminated by a concomitant maze operation. METHODS Left atrial function after Coxs maze operation performed concomitantly with a mitral valve operation was evaluated in 10 patients ranging in age from 38 to 67 years (mean age, 54 years). Seven patients who had had coronary artery bypass grafting served as the control group. Using transthoracic echocardiography, the ratio between the peak speed of the early filling wave and that of the atrial contraction wave (A/E ratio) and the atrial filling fraction (AFF) were determined from transmitral flow measurements. These two indices have been considered to represent the contribution of left atrial active contraction to ventricular filling. RESULTS The A/E ratio and the AFF were significantly lower in the maze group (0.35 +/- 0.17 versus 0.97 +/- 0.28 [p < 0.01] and 17.6% +/- 8.8% versus 36.8% +/- 6.4% [p < 0.01], respectively). The A/E ratio and the AFF correlated inversely with age (r = -0.72, p < 0.05 and r = 0.76, p < 0.05, respectively) in the maze group. In an angiographic study, the mean left atrial maximal volume index in the maze group was approximately three times larger than that in the control group (117.5 +/- 24.3 mL/m2 versus 35.3 +/- 6.6 mL/m2 [p < 0.01]). The left atrial active emptying volume index was significantly smaller in patients in the maze group (7.2 +/- 2.5 mL/m2 versus 13.1 +/- 4.6 mL/m2 [p < 0.01]). CONCLUSIONS After the maze procedure performed concomitantly with a mitral valve operation in patients with a dilated left atrium, left atrial contraction is detectable but incomplete in the elderly.
The Annals of Thoracic Surgery | 1992
Kenzo Yasuura; Yutaka Ogawa; Hiroshi Okamoto; Teiji Asakura; Motoaki Hoshino; Masaru Sawazaki; Akio Matsuura; Takashi Maseki; Toshio Abe
The use of profound hypothermia and total circulatory arrest in the surgical treatment of aortic dissection has previously been reported. However, the safe period of prolonged circulatory arrest with hypothermia remains controversial. We have developed a technique of hypothermic total body retrograde perfusion to achieve systemic organ protection: cerebral protection by continuous retrograde perfusion through the superior vena cava, myocardial protection by coronary sinus infusion, and abdominal visceral organ perfusion by continuous retrograde perfusion through the inferior vena cava. Our technique yields a relatively bloodless operating field and avoids hypoperfusion of vital organs through a false lumen.
The Annals of Thoracic Surgery | 1994
Toshiaki Itoh; Masaru Sawazaki; Yutaka Ogawa; Akio Matsuura; Kenzo Yasuura; Toshio Abe
A new accessory instrument to the self-retaining internal mammary artery retractor was developed. This instrument presses the chest wall inward, relieves the concavity of the inner surface of the chest wall, and provides good exposure of the internal mammary artery.
The Journal of Thoracic and Cardiovascular Surgery | 1994
Kenzo Yasuura; Hiroshi Okamoto; Yutaka Ogawa; Akio Matsuura; Teiji Asakura; Akira Seki; Motoaki Hoshino; Takashi Maseki; Masaru Sawazaki; Toshiaki Itoh; Toshio Abe
Aneurysms involving either the aortic arch or the proximal descending thoracic aorta in five patients were resected with the aid of profound hypothermic total body retrograde perfusion. Traditional surgical management of the aortic arch and the descending thoracic aorta necessitates clamping of the aorta. However, this technique may be associated with rupture or atheroembolism. Rupture occurring at the clamping site may be difficult to repair. Atheroembolism to the brain compromises the neurologic system, and multiple organ embolism is associated with disseminated intravascular coagulopathy. Atheroembolism in cardiovascular surgery has become increasingly prevalent. It is necessary to prevent clamp injuries and to preserve the function of the vital organs, such as the brain, heart, and liver, during aortic reconstruction. We applied a total body retrograde perfusion technique to operations for aortic aneurysms. Total body retrograde perfusion consists of cerebral protection by continuous perfusion through the superior vena cava, intermittent retrograde coronary perfusion through the coronary sinus, and continuous abdominal visceral perfusion through the inferior vena cava. It can yield a relatively bloodless operating field without the need for aortic clamping. We believe this new adjunct offers excellent results in the surgical treatment of aneurysms of the aortic arch or adjacent structures.
Scandinavian Cardiovascular Journal | 1996
Kenzo Yasuura; Akio Matsuura; Takashi Maseki; Ken Miyahara; Toshiaki Itoh; Toshiaki Ichihara; Masaru Sawazaki
Tricuspid regurgitation arising from chest trauma 46 years earlier was successfully corrected by valve reconstruction in a 67-year-old man. As the merits of valve repair are well established, it can be advocated for traumatic tricuspid regurgitation, regardless of the time from the causal injury.
The Japanese Journal of Thoracic and Cardiovascular Surgery | 2014
Masaru Sawazaki; Shiro Tomari; Kenta Zaikokuji; Yusuke Imaeda
Mitral valve plasty has superseded valve replacement as the standard technique for treating degenerative mitral valve prolapse. Quadrangular resection is considered the gold standard for posterior leaflet prolapse. Chordal replacement was first developed to treat the anterior leaflet and subsequently became widely used for the posterior leaflet, after which a new version of posterior leaflet resection was developed that did not involve local annular plication. In the era of the mini-thoracotomy, the premeasured loop technique is simple to adopt and is as durable as quadrangular resection. However, there is controversy surrounding whether resection or chordal replacement is the optimal technique. The resection technique is curative because it removes the main pathologic lesion. The disadvantage of the resection is that it can be complicated and often requires advanced surgical skills. In contrast, chordal replacement is not pathologically curative because it leaves behind a redundant leaflet. However, the long-term results appear to be equivalent in many reports. Functionally, chordal replacement retains greater posterior leaflet motion with a lower trans-mitral pressure gradient than quadrangular resection. Moreover, chordal replacement is simple and yields uniform results. The optimal technique depends on whether the anterior leaflet or posterior leaflet is involved, the Barlow or non-Barlow disease state, and whether a mini-thoracotomy or standard sternotomy approach is used. For mitral valve repair, the most superior and reliable technique for the posterior leaflet is resection using the newer resection technique with a sternotomy approach, which requires a skilled surgeon.
The Japanese Journal of Thoracic and Cardiovascular Surgery | 2017
Kenta Zaikokuji; Masaru Sawazaki; Shiro Tomari; Yusuke Imaeda
Unroofed coronary sinus syndrome (URCS) is a rare congenital cardiac anomaly. Recently, cardiac surgery using a minimally invasive approach has become the preferred treatment, affording better cosmetic results and a more rapid post-operative recovery than the traditional method. We report the case of a 54-year-old male in whom partial URCS was treated via a totally endoscopic repair technique featuring right mini-thoracotomy.
The Japanese Journal of Thoracic and Cardiovascular Surgery | 2015
Masaru Sawazaki; Shiro Tomari; Kenta Zaikokuji; Yusuke Imaeda
A mobile plaque in the ascending and transverse aorta increases the risk of cerebral infarction during treatment of an arch aneurysm. A previous report described an isolation technique for replacing the ascending and transverse aorta with a mobile atheroma by selective hypothermic antegrade cerebral perfusion (Shiiya et al., Ann Thorac Surg 72:1401–1402, 2001). Here, we present an improved isolation technique for more severe conditions, such as shaggy aorta and shaggy brachiocephalic artery, in two patients. First, we anastomosed both axillae arteries with grafts and placed drainage cannulae in the superior and inferior venae cavae prior to filling the cardio-pulmonary bypass system with blood. Next, we cannulated the right common carotid artery and selective cerebral perfusion was started prior to cannulation and perfusion of the left common carotid artery. Systemic perfusion was then initiated through the axillae grafts. Both patients who underwent this procedure recovered without neurologic complications.
The Japanese Journal of Thoracic and Cardiovascular Surgery | 2009
Koji Takai; Masaru Sawazaki; Shiro Tomari; Koji Yamana; Yutaka Ogawa
PurposePatient data related to cardiovascular surgery are usually managed separately by surgeons and clinical engineers in their respective data files. Recently, with our participation in the Japan Adult Cardiovascular Surgery Database (JACVSD), we newly prepared JACVSD-ready cardiovascular surgery data files by combining two data entry systems.MethodsWe constructed a cardiovascular surgery database system using FileMaker Pro and FileMaker Server. When preparing the data files, we attempted to eliminate excessive labor during data input and to enable easy distinction of items for which input has not been completed. In addition, we added some items required for clinical work so the files could be used not only for registration with the JACVSD but also for clinical work.ResultsAll the items for the cases in 2005 and 2006 were input by the end of each year. Registration in the JACVSD in 2005 and 2006 was completed by the set deadline, except in one case in which the patient remained hospitalized at the time of the deadline.ConclusionsOur newly developed JACVSD-ready data files have increased the interest of surgeons in data entry and in collecting data. With the new system, we can manage patient data more easily and more effectively at low cost.