Fumio Chikugo

Technique for Constructing the Pulmonary Trunk for Tetralogy of Fallot With Pulmonary Atresia

In expectation of the growth of a new pulmonary arterial trunk in total correction of tetralogy of Fallot with pulmonary atresia, we used pedicled autologous pericardium combined with left atrial appendage as the posterior wall of a new pulmonary arterial trunk. In cases of long discontinuity between the right ventricular infundibulum and left pulmonary artery, our technique could be recommended for early repair of tetralogy of Fallot with pulmonary atresia.

Angiotensin II as a stimulator of Na+-dependent Ca2+ efflux from freshly isolated adult rat cardiomyocytes

In cardiac tissues, angiotensin II causes inotropic and chronotropic effects on the heart. It is indicated that the mechanism of the inotropic effect of angiotensin II is attributed to an increase in cytosolic free calcium ([Ca2+]i) in cardiomyocytes. However, increased [Ca2+]i should be restored to a physiological level because cumulative elevation in [Ca2+]i leads to irreversible injury in cardiomyocytes. Whereas it is known that angiotensin II causes the increase in [Ca2+]i in cardiac cells, little is known about the mechanisms of decrease in [Ca2+]i in cardiomyocytes upon angiotensin II stimulation. In the present study, we examined the effect of angiotensin II on Ca2+ efflux from freshly isolated adult rat cardiomyocytes. Angiotensin II stimulated the efflux of 45Ca2+ from the cells in a concentration-dependent manner (10(-7)-10(-5) M). The 45Ca2+ efflux from the cells was inhibited by type 1 angiotensin II receptor inhibitor. The angiotensin II-stimulated 45Ca2+ efflux was not affected by deprivation of the extracellular Ca2+, but was dependent on the presence of extracellular Na+. These results indicate that angiotensin II stimulates extracellular Na(+)-dependent 45Ca2+ efflux from freshly isolated adult rat cardiomyocytes, probably through its stimulatory effect on the plasma membrane type 1 angiotensin II receptors which may couple to Na+/Ca2+ exchange.

Efficacy and Optimal Timing of Endovascular Treatment for Type B Aortic Dissection

OBJECTIVES To determine the efficacy and the optimal timing of thoracic endovascular aortic repair (TEVAR) for closing the primary entry in uncomplicated patients with chronic type B aortic dissection and a patent false lumen (FL). METHODS Thirteen patients underwent TEVAR for aortic dissection between 2008 and 2012. These patients had chronic dissection with a patent FL and expansion of the aorta. Early TEVAR was performed for five patients within 1-7 months from the index dissection (TEVAR-EC group) and delayed TEVAR was performed for eight patients within 1-16 years (TEVAR-DC group). Changes in the diameters and volumes of the true lumen (TL) and FL and the aortic remodeling were assessed by multidetector computed tomography for 3 years after TEVAR. RESULTS The reduction rate of FL in the thoracic aorta was notably higher in the TEVAR-EC group than in the TEVAR-DC group regardless of the presence or absence of distal retrograde flow. There was a significant TL expansion despite different timings of TEVAR. CONCLUSIONS Early TEVAR resulted in good prognosis and preferable aortic remodeling in uncomplicated patients with chronic type B aortic dissection and a patent FL, and we recommend early TEVAR within seven months after the index dissection.

Delayed aortic injury caused by sharp rib fracture.

A 55-year-old woman was transported to the hospital by ambulance after jumping in a suicide attempt. She was intubated immediately because of breathing difficulty with a flail chest. Computed tomography showed pulmonary contusion, multiple left rib (3th to 8th) fractures, and injury to the ascending thoracic aorta (Figure 1). We decided to delay aortic surgery until she recovered consciousness because of suicide-related injury. She underwent ascending aortic replacement on the 11th post-trauma day. Her hemodynamic measurements were stable, and 3 days after the operation, she was weaned from the ventilator. However, 3 h later, her systolic blood pressure suddenly changed to shock conditions. Computed tomography revealed that the bleeding source was a puncture site in the descending thoracic aorta (Figure 2). Her hemodynamic condition deteriorated, and she died before she was taken to operating room. The cause was determined to be a sharp bone particle of the 7th rib, which was angulated and perpendicular to its original position, and had lacerated the descending aorta (Figure 3).

A case of reoperation 24 years after repair of absent pulmonary valve syndrome with anomalous origin of the left pulmonary artery

We experienced a case of a 38-year-old woman with a persistent cough, 24 years after repair of absent pulmonary valve syndrome with anomalous origin of the left pulmonary artery. The right pulmonary artery was massively dilated, thus it caused the compression of the bronchi, which was thought to result in her respiratory symptom. This dilatation of the right pulmonary artery seemed to have progressed because of the following two reasons. The first is the pulmonary hypertension caused by the late reconstruction of the left pulmonary artery. The second is residual pulmonary stenosis and regurgitation after the initial operation without a pulmonary valve insertion. We performed a reoperation consisting of reconstruction of the right ventricular outflow tract using a valved conduit and plication of the right pulmonary artery. Her postoperative course has been without any complications and satisfactory for the past 2 years.

Surgical Therapy for Prosthetic Graft Infection.

治療に難渋した人工血管感染5症例について検討した. 年齢は57～81歳, 初回手術時の基礎疾患は Leriche 症候群1例を含む閉塞性動脈硬化症3例, 悪性腫瘍の動脈浸潤2例であった. 人工血管感染部位は鼠蹊部3例, 膝上部1例, 腹部1例で, うち4例の起炎菌は Staph. aureus (MRSA3例) であった. 感染原因となった人工血管の手術から感染発現までの期間は, 腹膜炎症例は10日と短く, 末梢側の感染では2か月～14年と長かった. 腹膜炎例を除いた症例での感染巣のドレナージ, 洗浄等の保存的治療期間は40～64 (平均50) 日であった. 手術はグラフトの感染部位のみの除去またはグラフト全部を摘出し, 新たな血行再建術を施行した. 感染グラフトはPTFE4例, Woven-Dacron 1例で, 再手術にも同様のグラフトを用いた. 感染部を避けるため, 閉鎖孔経由など3例で別経路を用いた. 感染人工血管の全摘出が困難な症例では, 感染巣部のみの人工血管摘除と健常な周囲組織での再建術を行い良好な結果を得た. 手術成績は全例生存, 敗血症や下肢切断等の重篤な合併症は認めなかった. 再手術から現在までの8か月～8年間, 全例開存し再感染も認めていない.