Tadao Kugai

Rupture in a mitral papillary muscle following blunt chest trauma

The successful surgical repair of an uncommon case of blunt chest trauma is described. A 28-year-old man was involved in a motorcycle accident during which the victim struck a pole at high speed. Extracorporeal membrane oxygenation was required with a tentative diagnosis of traumatic respiratory distress syndrome, but he nevertheless continued to show progressive deterioration. In the preoperative evaluation, transesophageal echocardiography clearly demonstrated an injury involving of mitral regurgitation secondary to total rupture of a papillary muscle. Mitral valve replacement was performed seven days after the accident. The importance of the diagnostic process and surgical treatment are emphasised.

Rescue Balloon Pulmonary Angioplasty Under Veno-Arterial Extracorporeal Membrane Oxygenation in a Patient With Acute Exacerbation of Chronic Thromboembolic Pulmonary Hypertension

We describe a case of a 41-year-old woman with acute exacerbation of chronic thromboembolic pulmonary hypertension (CTEPH) complicated by rapidly progressive respiratory failure and right heart failure with cardiogenic shock. A computed tomography (CT) showed thrombi in the right main pulmonary artery and bilateral peripheral pulmonary arteries, and echocardiography showed right ventricular dilatation and tricuspid regurgitation, with an estimated pressure gradient of 80 mmHg. The patient was initially diagnosed with acute pulmonary thromboembolism, and thrombolytic therapy was administered. Her condition subsequently deteriorated, however, necessitating mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We performed emergency catheter-directed thrombectomy and thrombus aspiration. Pulmonary hypertension (PH) temporarily improved, but subsequently worsened, and the patient was diagnosed with CTEPH. Pulmonary endarterectomy (PEA) was performed. After PEA, we were unable to wean the patient off VA-ECMO, and rescue balloon pulmonary angioplasty (BPA) to the middle and inferior lobe branches of the right lung was performed. Five days after BPA, the patient was removed from VA-ECMO and on the 57th day of hospitalization, she was weaned off the ventilator. The patient was discharged after 139 days of hospitalization. Rescue BPA represents a useful intervention for improving PH and weaning off VA-ECMO in a patient with acute exacerbation of CTEPH.

Clinical studies on the vasodilating and anti-platelet effects of OP-41483, a prostacyclin derivative

The vasodilating and anti-platelet actions of OP-41483 was studied to determine the effective dose of this drug for the treatment of ischemic lower limbs. The compound was given to 11 patients intravenously at rates of 2.5, 5.0 and 10.0 ng/kg/min. Infusion at a rate of 10 ng/kg/min increased the mean flow rate of the tibial arteries from 3.15±1.77 ml/min before the infusion, to 7.89±2.51 ml/min (p<0.001) and to 6.38±3.19 ml/min (p<0.001), at the time of, and 60 minutes after the cessation of the infusion, respectively. The peripheral flow resistance of the tibial arteries was reduced from 2.1±1.12×105 dyne·sec/cm5 before the infusion to 0.9 ±0.33×105 dyne·sec/cm5 (p<0.001) and to 1.2±0.78×105 dyne·sec/cm5 (p<0.05), at the time of, and 60 minutes after the cessation of the infusion. ADP-induced platelet aggregation was reduced from 73.3±17.6% before the infusion to 50.7±24.5% (p<0.01) and to 64.0±23.5% (p<0.05), at the time of, and 60 minutes after the cessation of the infusion, respectively. Collageninduced platelet aggregation was also reduced from 71.4±24.0% to 66.6±21.5% before and after the infusion (p<0.05).

Amiodarone-Induced Hyponatremia Masked by Tolvaptan in a Patient with an Implantable Left Ventricular Assist Device

A 43-year-old man was referred to our hospital in June 2014 because of severe heart failure. He was diagnosed with familial dilated cardiomyopathy and was administered oral tolvaptan and amiodarone for atrial and ventricular tachycardia. Since up-titration of carvedilol had failed and he was dependent on dobutamine, a left ventricular assist device (LVAD) was implanted. Tolvaptan and furosemide were both discontinued after LVAD implantation and he was discharged from the hospital. Thirteen months later, he was hospitalized for lethargy and hyponatremia of 108 mEq/L, with an antidiuretic hormone level of 2.5 pg/mL, which suggested syndrome of inappropriate antidiuretic hormone secretion (SIADH). We discontinued amiodarone and administered fludrocortisones. However, hyponatremia persisted for a few more days, eventually resulting in delirium and damage to the LVAD driveline. He received an urgent pump exchange and hyponatremia was gradually improved. We considered the possibility that amiodarone-induced SIADH was masked by tolvaptan therapy before LVAD implantation.

Life-Saving Resection of a Huge Intrapericardial Teratoma in a Newborn

生後5日目の女児,アプガー8点,34週,体重3,460gで出生した.生後2日目より多呼吸,心室性期外収縮,発熱のため当院に紹介入院となった.心エコーと胸部CTにて巨大な腫瘍と多量の心嚢液が心臓を圧迫し,心タンポナーデを呈していた.人工心肺stand-by下で腫瘍を完全に摘出した.腫瘍は上行大動脈から発生し,骨,気管上皮,唾液腺,中枢神経などを有するmature teratomaであった.AFPは術前25,910ng/mlから退院時630ng/ml,さらに現在1.5歳で6.7ng/mlと正常化し,再発傾向もない.心嚢内奇形腫は新生児心臓腫瘍のなかでもまれなもので,かつ進行性の呼吸循環不全に陥るため,救命には早期診断と早期手術が重要である.