Prostaglandins have been shown to contribute to the pathogenesis, progression and exacerbation of ischemic heart disease. Prostaglandins have also reported to contribute to the arrhythmogenesis of lethal arrhythmias during ischemia and reperfusion. In this review article, The electrophysiologic effects of prostacyclin, its stable analogues, thromboxane A₂ and its stable analogue were reviewed, and described the in vitro effects of a stable analogue of prostaglandin, and a stable analogue of thromboxane A₂ in our laboratory. Finally, the electrophysiologic and metabolic effects of a thromboxane A₂ synthetase inhibitor on the coronary artery occlusion/reperfusion model were studied in our laboratory. The prostacyclin analogue shortened the action potential duration in a normal Tyrode′s solution, and shifted the Vmax - resting membrane potential curve rightward. The TXA₂ analogue did not exhibit any electrophysiologic effects on the normal, high K⁺, and simulated ischemia conditions. Intracoronary administration of the TXA₂ analogue led to marked surface and epicardial ECG ST segment elevation and the subsequent development of ventricular tachycardia. The thromboxane A₂ synthetase inhibitor elicited significant reduction of ventricular premature contractions and tended to reduce reperfusion-induced ventricular fibrillation. The rise in extracellular K⁺ concentration of the ischemic myocardium was markedly decreased in the thromboxane A₂ synthetase inhibitortreated group. Therefore, prostacyclin may be antiarrhythmic through its direct electrophysiologic effects, i.e., recovery of Vmax leading to improvement of conduction delay during ischemia, and thromboxane A₂ may be arrhythmogenic not through its direct electrophysiologic effects on the ischemic myocardium, but through exacerbation of ischemia due to its potent vaso-constrictive effects.

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Background: Flipped classroom methodologies have gained popularity and undergone much research scrutiny in recent years. However, there have been no studies examining the effects of flipping an English, first-year, basic medical history taking, oral communication skills course in Japan. Methods: A 1-year prospective cohort of students (n = 135) enrolled in an English, basic medical history taking course (30 hours) was taught using a flipped approach. A historical cohort of students (n = 128) was taught using a more conventional task-based communicative approach (45 hours) for comparison. Baseline metrics indicated that there was adequate similarity for comparison between the two groups. Performance examination scores were analyzed to assess effectiveness in 4 categories: Spoken English Proficiency (SEP); Communication and Interpersonal Skills (CIS); Integrated Clinical Encounter (ICE); Comprehension (Comp.). Results: The overall average examination score increased from 67.5 ± 1.5% (mean ± SE) in 2014 to 77.5 ± 1.5% in 2015 (mean difference between the groups, 9.6%; [95 percent CI, 5.5% to 13.7%], P ⟨ .001) indicating a significant improvement in student performance. Largest gains were observed in SEP and CIS and there were no significant changes in the ICE and Comp. categories. Conclusion: It appears that students performed significantly better in a basic history taking examination with a simulated patient in English after having been taught using the “Flipped Classroom” method, despite having had 15 fewer classroom hours. Therefore, it is worth considering this innovative methodology as a means to improve educational effectiveness.

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ST-T alternans during ischemia is associated with ventricular arrhythmias and reflects primary changes in repolarization, and changes secondary to 2:1 conduction block. We studied the effect of pinacidil, an ATP-sensitive K⁺ channel activator, on the incidence of ST-T alternans during ischemia. K⁺- and pH-sensitive electrodes and unipolar and bipolar electrodes were inserted into the midmyocardium in 9 open-chested pigs. Transmembrane action potentials were recorded from the epicardial surface. The carotid artery was shunted to the left anterior descending artery via a roller pump, and 25 μM pinacidil was infused. Prior to pinacidil administration, ST-T alternans occurred in all 9 pigs during control ischemia, at a mean onset time of 4 minutes 23 seconds ± 22 seconds. After pinacidil infusion, no ST-T alternans occurred during the 8-minute ischemic period. Furthermore, after pinacidil infusion, the final rise in extracellular K⁺ ([K⁺]_e) and the fall in extracellular pH (pH_e) were similar to the those at the onset of ST-T alternans under control conditions ([K⁺]_e : 7.6 ± 0.9 vs. 6.9 ± 0.9 mM; pH_e: 7.08 ± 0.78 vs. 7.05 ± 0.18). Activation delay was also similar with pinacidil administration compared with that at the onset of ST-T alternans, under the control condition (27 ± 18 ms vs. 34 ± 24 ms). With pinacidil, the action potential duration after 8 minutes of ischemia was decreased by 50% (from 250 ± 36 ms to 127 ± 15 ms). The complete suppression of ST-T alternans by pinacidil may reflect an increase in the diastolic interval.

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Background: Both contact force (CF)-guided radiofrequency ablation (RFA) based pulmonary vein isolation (PVI) and second-generation cryoballoon ablation (CBA) based PVI may improve the procedural outcome. However, the clinical outcome after RFA- and CBA-based PVI remains unclear. Adenosine or adenosine triphosphate (ATP) administration after PVI is useful to detect dormant PV conduction (DC) after the ablation procedure, and the presence of DC has been shown to be related to AF recurrence. Methods: Out of 100 patients with paroxysmal AF (PAF), 50 underwent CF-guided PVI (25-30 W, 30 sec for each ablation: CF-RFA group), and the remaining 50 patients underwent cryoballoon ablation-based PVI (3 min cooling + 2 min bonus cooling for each PV: CBA group). Thirty minutes after PVI, a 30-mg bolus of ATP was administered. We compared the success rate of PVI, and incidence of DC after PVI between the CF-RFA and CBA groups. Results: The subsequent response was assessed for each vein using a ring catheter. In the CBA group, 180 (90%) of 200 PVs were isolated and 20 PVs (10%) (2 left superior PV (LSPV), 3 left inferior PV (LIPV), 4 right superior PV (RSPV), 11 right inferior PV (RIPV) from 14 of 50 patients (28%) required additional RFA because of residual potential at the PV or PV antra. After a waiting period of 30 min after the last energy application, acute PV reconduction was observed spontaneously in 13 PVs (6.5%) (6 LSPV, 3 LIPV, 4 RSPV) from 12 patients (24%) in the CF-RFA group. The DC sites provoked by ATP were 13 PVs (6.5%) (5 LSPV, 3 LIPV, 2 RSPV, 3 RIPV) from 8 patients (16%) in the CF-RFA group, compared with 9 PVs (4.5%) (2 LSPV, 4 LIPV, 1 RSPV, 2 RIPV) from 9 CBA patients (18%) (P = 1.000). AF recurred in 6/50 (12%) in both the CF-RFA and CBA groups at 1 year after the ablation (P = 1.000). Conclusions: There was no significant difference in the incidence of DC after PVI and the 12-month AF-free rate between the second-generation CBA- and CF-based RFA.

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超低出生体重 (ELBWI)，慢性肺疾患 (CLD) に伴う肺高血圧 (PH) の既往のある8 か月男児について報告する．外来定期受診時にPH クリーゼとなり蘇生を要した．肺血管拡張薬を導入しPH は改善し，在宅酸素で退院した．ELBWI には高率にCLD を合併し，本症例のような重症例ではPH のため予後不良となる患者が存在する．ルーチンの心臓超音波検査だけでは過小評価となる可能性があり，適切なリスクの評価とさらなる注意深いフォローが求められる．

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1 歳女児が膿瘍形成を伴う皮膚軟部組織感染症を発症した．再発例でかつ家族内感染例であるため家族全員から検体を採取し，細菌培養検査から全て MRSA を検出し，遺伝子解析で USA300 株を同定した．家族全員に除菌を行い1 年が経過したが，母親以外に再発は認めず除菌は有効であったと考えた．母親が皮膚軟部組織感染症を再発した要因として，アトピー性皮膚炎のコントロール不良が考えられた．

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日本の結核患者数は減少傾向が続いているが，交通網が発達し，外国人労働者や訪日外国人が増加することに伴い，日本における外国人結核患者登録数は年々増加している．我々は，結核感染した外国籍の父と潜在性結核感染症と診断された外国籍の母から出生した児の1 例を経験した．今後，本症例のような潜在性結核感染母体からの出生例が増加することも考えられ，その対応について検討する必要がある．

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HALS (Hand-assisted laparoscopic surgery) は1995年にKusminsky RE が脾摘出術を報告してから，様々な疾患に応用されている．今回十二指腸潰瘍穿孔症例に対し，HALS を用いて大網充填を行い良好な術後経過を得たので報告する．症例は，43 歳男性．2016 年1 月心窩部痛出現し，徐々に増悪したため救急要請し当院に搬送された．同日，上部消化管穿孔の診断で緊急手術となった．上腹部正中切開にて開腹しGelPort^® を装着後，臍直下に12 mm，左側腹部に5 mm，右側腹部に12 mm と5 mm のトロッカーを挿入し，腹腔内洗浄後，直視下にて大網充填を行った．術後合併症は認めず，術後14 日目に退院となった．HALS は直視下手術の触覚と鏡視下手術の視野を得られるといった両方の側面を持っており上部消化管穿孔に対し有意な手術手技の1 つと考える．

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緊急開腹胆嚢摘出術を要した胆嚢捻転症の2 例を経験したので報告する．2 例とも超音波では急性胆嚢炎を示唆する胆嚢腫大と壁肥厚を認めた．しかし腹部CT では肝床部より尾側に大きくシフトした遊走胆嚢が確認されたため胆嚢捻転症と診断した．本疾患は比較的稀であるがその症状は特徴的ではなく，本疾患が示唆される際には緊急手術が必須となるため，急性胆嚢炎の鑑別疾患として本疾患を常に念頭におくべきである．

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症例は1 歳4 か月女児．高度肝機能障害のため当院に搬送された．急性肝不全と診断し，頸部リンパ節腫脹を除く川崎病主要症状5/6 を認めたことから，川崎病の併存を考えた．血漿交換を含む集学的治療を行い，肝移植可能な施設へ転院とした．生体肝移植が施行され，術後指趾の膜様落屑を認めた．川崎病に伴う急性肝不全は過去に報告がない．今後，川崎病と重症肝障害の症例が集積され，さらなる追究が行われることが望まれる．

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