Yoshiro Matsui

Background: Left ventricular assist device (LVAD) therapy has improved the clinical outcomes in advanced heart failure patients, however, this may differ between countries. We aimed to compare outcomes between Japanese and US LVAD cohorts. Methods: For 416 consecutive LVAD patients who received HeartMate II LVAD implantation and completed a one-year follow-up, age-matched Japanese patients (the Japanese registry for mechanically assisted circulatory support (J-MACS) group) and the US patients were compared for their clinical outcomes. Results: 154 J-MACS patients and 77 US patients were compared. Survival, free from hemocompatibility-related adverse events (HRAEs) in the J-MACS was statistically comparable with the US (75% vs. 63%, p = 0.79). J-MACS had more disabling strokes than the US (0.221 vs. 0.052/patient-year, p = 0.005), whereas there was less nonsurgical bleeding (0.045 vs. 0.117/patient-year, p = 0.024). The net hemocompatibility score was statistically comparable between the groups (1.54 vs. 1.19 points/patient, p = 0.99). Post-LVAD prothrombin time with international normalized ratio (INR) 3.0 (odds ratio 5.71) was a risk factor in the US (p < 0.05 for both). Conclusion: In the age-matched cohorts, the J-MACS group experienced more strokes, while the US group had more bleedings. “Tailor-made” therapeutic strategy might be required for each country, given the unique variation of HRAE incidence among each country.

Atrial metabolic disturbance contributes to the onset and development of atrial fibrillation (AF). Autophagy plays a role in maintaining the cellular energy balance. We examined whether the altered atrial expression of genes related to fatty acid metabolism is linked to that related to autophagy in chronic AF. Right atrial tissue was obtained during heart surgery from 51 patients with sinus rhythm (SR, n=38) or chronic AF (n=13). Preoperative fasting serum free-fatty-acid levels were significantly higher in the AF patients. The atrial gene expression of fatty acid binding protein 3 ( FABP3 ), which is involved in the cells’ fatty acid uptake and intracellular fatty acid transport, was significantly increased in AF patients compared to SR patients; in the SR patients it was positively correlated with the right atrial diameter and intra-atrial EMD, parameters of structural and electrical atrial remodeling that was evaluated by an echocardiography. In contrast, the two groups’ atrial contents of diacylglycerol (DAG), a toxic fatty acid metabolite, were comparable. Importantly, the atrial gene expression of microtubule-associated protein light chain 3 ( LC3 ) was significantly increased in the AF patients, and autophagy-related genes including LC3 were positively correlated with the atrial expression of FABP3 . In conclusion, in chronic AF patients, the atrial expression of FABP3 was upregulated in association with autophagy-related genes without altered atrial DAG content. Our findings may support the hypothesis that dysregulated cardiac fatty acid metabolism contributes to the progression of AF and induction of autophagy has a cardioprotective effect against cardiac lipotoxicity in chronic AF.

This study aimed to determine the usefulness and limitations of videoassisted thoracoscopic (VATS) lobectomy using one-window and puncture method (1WPM). This study involved 14 patients who underwent lobectomy using the 1WPM at our institute from 2008 to 2017. The study patients comprised of 3 men and 11 women with a median age of 10.5 years (range, 0-72 years). There were eight cases in children younger than 18 years old and the youngest patient was 9 days old. The diagnoses were congenital pulmonary cystic disease (n = 7), primary lung cancer (n = 4), metastatic lung tumor (n = 1), and others (n = 2). The 1WPM was successful in 9 of 14 patients (64.3%) and, in 5 cases (35.7%), needed conversion to either two-window method (TWM) using additional port (n = 3) or open thoracotomy (n = 2). The causes for conversion were need for additional bronchoplasty or lymph node dissection (n = 3), failure of one-lung ventilation (n = 1), and presence of a small thoracic cavity that made the procedure extremely difficult (n = 1). In the group that was successfully treated with 1WPM, the median values were as follows: operation time, 193 min (range, 112-480 min); blood loss, 0 ml (range, 0-90 ml); drainage duration, 1 day (range, 1-4 days); and postoperative hospital stay, 7 days (range, 4-13 days). Lobectomy by 1WPM can be safely performed and has good postoperative course and this procedure can be applicable and effective in small infants.

Since a displaced bronchus related to the left upper lobe is an uncommon anatomical anomaly, it has a risk of being accidentally resected during left upper lobe resection unless they are identified preoperatively. A case of video-assisted thoracic surgery (VATS) segmentectomy that was safely performed under preoperative identification of a displaced subsegmental bronchus and anomalous pulmonary vessels is presented. A 48-year-old woman visited our hospital because of an abnormal shadow on a radiograph on a health check. The chest computed tomography (CT) showed a multicystic mass with a diameter of 35 mm on dorsal interlobar parenchyma between the S1+2 and S6 segments in the left lung. The three-dimensional (3D) CT with multiplanar reconstruction showed that B1+2b+c passed to the dorsal side of the left main pulmonary artery (PA), which was considered a displaced bronchus. The branch of A6 arose from the left main PA at the level of the branches of A3 and A1+2, more proximal than the normal anatomy, and passed to the dorsal side of a displaced B1+2b+c. The branch of V1+2 passed between B6 and the bronchus to the basal segment and joined V6 at the dorsal side of the pulmonary hilum. Intraoperative findings of the anatomy of the bronchi and pulmonary vessels were exactly the same as the preoperative 3D CT findings, so segmentectomy of S1+2b+c and S6 by VATS was performed safely. Then there were accessory fissures between S1+2 and S3 and between S6 and the basal segment. The pathological diagnosis was a left lung abscess. A preoperative 3D CT may be helpful for identifying anatomical anomalies. An anatomical anomaly should be suspected if accessory fissure is found during surgery.

Ideally, an annuloplasty ring’s shape should be changed intraoperatively if mitral valve repair is unsuccessful because of a short coaptation length or systolic anterior motion. Several post-implantation adjustable rings have been developed, but they are not freely deformable and are unsuitable for asymmetric repair of the valvular annulus. We developed a novel thermally deformable mitral annuloplasty ring to address these problems and assessed the ring’s mechanical properties and its effect on the mitral valve anatomy. This ring was made of polycaprolactone. Tensile and bending tests were performed to evaluate the ring’s mechanical properties. The ratio of the transverse and septal–lateral length was determined as 4:3. Using 10 pig hearts, we measured the post-deformation coaptation length and minimum distance from the coaptation to the ventricular septum, which is a factor of abnormal systolic anterior motion of the mitral valve. In the mechanical tests, the ring’s yield point was greater than the deformation force of the annulus in humans. In pigs with deformation from “4:3” to “4:2”, the coaptation length was significantly increased in each mitral valve part. In pigs with deformation from “4:3” to “4:4”, the minimum distance from the coaptation to the ventricular septum was significantly increased. Asymmetrical ring deformation increased the coaptation length only at the deformed area. In conclusion, this new thermally deformable mitral annuloplasty ring could be “order-made” to effectively change the coaptation length in all parts of the mitral valve and the distance from the coaptation to septum post-deformation via intraoperative heating.

冠動脈肺動脈起始症（ACAPA）は稀な先天性冠動脈異常であり，多くは幼少期に手術介入を要する．右冠動脈肺動脈起始症（ARCAPA）は左冠動脈肺動脈起始症（ALCAPA）よりもさらに稀である．われわれは成人期のARCAPAに対する手術症例を経験した．症例は60代女性，主訴は胸痛．冠動脈CTおよび冠動脈造影で，左前下行枝・中隔枝より発達した側副血行路が右冠動脈を逆行性に灌流し，主肺動脈に流入することを確認した．肺体血流比は1.21であった．心臓MRIで右冠動脈と左前下行枝の領域に虚血所見を認めた．手術は，右冠動脈の上行大動脈への再移植（reimplantation）と肺動脈パッチ形成を施行した．術翌日に抜管し一般病棟へ転棟，術後18日目に退院となった．術後15カ月が経過した現在，胸部症状なく外来通院中である．成人期のARCAPAに対し手術を施行し良好な結果を得たので報告する．

Unicuspid aortic valve in an adult is extremely rare. In addition, 90% of the patients with aortic coarctation are reported to die before the age 50. A 60-year-old woman was admitted to our hospital for further examination of exertional dyspnea which had begun one year before. She had been under medical treatment for hypertension since early thirties, and had been also diagnosed with moderate aortic stenosis at 50 years of age. She was at 1st diagnosed with aortic coarctation combined with bicuspid aortic valve stenosis. The aortic valve was then found unicuspid and was replaced under cardiopulmonary bypass with perfusion to both the ascending aorta and the femoral artery. Repair of aortic coarctation was performed 3 months later through left thoracotomy without extracorporeal circulation due to the rich collateral circulation. She had no postoperative complications, and hypertension as well as ankle-brachial index improved to the normal levels.