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The REBa2Cu3Oy (REBCO) superconducting magnet requires low-resistance and high-mechanical-strength splices from a standpoint of magnet manufacturing. In the previous study, we designed a prototype REBCO sextupole magnet. To fabricate the sextupole magnet, it is important to characterize low-temperature and high-magnetic-field performances of the splice resistance of REBCO tapes. For that reason, we measured the splice resistance of 4-mm-wide commercial REBCO tapes of three manufacturers at 77 and 4.2 K in this study. The magnetic field characteristics of the splice resistance was determined up to 10 T at 4.2 K. Parameters such as solder compositions and splicing orientations of two REBCO tapes were varied to clarify the impact of each on the splice resistance characteristics. The splice resistance was determined primarily by the splicing orientation of two REBCO tapes. The minimum splice resistance of the 40-mm-long joint was approximately 16.5 nΩ at 4.2 K and in self-field when REBCO layers of two tapes were in closest orientation. The critical current and n-value of the splice section showed no appreciable degradation compared to those of the original tape.

Background The clinical relevance of examining human atrial natriuretic peptide (HANP) or left atrial appendage (LAA) wall-motion velocity during sinus rhythm in paroxysmal atrial fibrillation (AF) patients has not been clearly elucidated. Methods The subjects were 38 patients with paroxysmal AF who underwent transesophageal and transthoracic echocardiography during sinus rhythm. The presence of spontaneous echocontrast (SEC) was examined with transesophageal echocardiography and LAA wall-motion velocity (LAAWV) was measured with transthoracic tissue Doppler echocardiography. Plasma HANP was measured within 3 hours after echocardiography. Results Human atrial natriuretic peptide ranged from 12 to 106 pg/mL with an average of 43 ± 24 pg/mL and had a significant correlation with LAAWV (r = −0.57) or LAA flow velocity (r = −0.41). HANP was significantly higher in patients with SEC than in patients without SEC (64 ± 29 vs. 34 ± 15 pg/mL, P = 0.008) and LAAWV was significantly lower in patients with SEC than in patients without SEC (13 ± 5 vs. 20 ± 5 cm/sec, P = 0.002). HANP >44 pg/mL had a sensitivity of 73% and specificity of 89% for diagnosing SEC. SEC was more frequently observed (73%) in patients with HANP >44 pg/mL and/or LAAWV

Left ventricular thrombus (LVT) after acute myocardial infarction (AMI) is a risk factor for embolic complications. Although warfarin has traditionally been used to treat LVT, it has relevant disadvantages that limit its use. We herein describe the case of a 78-year-old man with AMI who had a history of paroxysmal atrial fibrillation. Following 10 days of urgent coronary reperfusion therapy, transthoracic echocardiography revealed a moderately sized LVT in the apex, which subsequently disappeared after 18 days of treatment with dabigatran. This case demonstrates that dabigatran may represent an alternative to warfarin as a therapeutic option in patients with LVT after AMI.

This study examined the role of left atrial (LA) appendage wall velocity (LAAWV) measurement in addition to LA size for the noninvasive assessment of thrombogenesis in patients with atrial fibrillation (AF) and normal plasma D-dimer levels.In 58 non-valvular AF patients, LAAWV and the LA volume index (LAVI) were determined by transthoracic echocardiography. LA appendage flow velocity and severity of spontaneous echo contrast (SEC) were determined by transesophageal echocardiography.LAAWV was strongly correlated with LA appendage flow velocity (r = 0.82), and LAVI was weakly correlated with LA appendage flow velocity (r = -0.37). As SEC severity increased, LAAWV decreased (p0.001) and LAVI increased (p0.001). Among 52 patients with normal D-dimer levels, LAAWV10 cm/s had 71 % sensitivity and 94 % specificity for diagnosing severe SEC. Severe SEC was not found in 18/32 large LAVI patients (34 mL/m(2)), but 17 of the 18 patients (94 %) had LAAWV10 cm/s. Severe SEC was found in 3/20 patients with normal LAVI, but all of them showed LAAWV10 cm/s.The noninvasive measurement of transthoracic LAAWV in addition to LA volume is clinically relevant for quantitatively assessing thrombogenesis in AF patients with normal D-dimer levels.

Myocardial Mass in Sarcoidosis. Sarcoidosis is a granulomatous disease that may involve multiple organ systems. The prognosis of sarcoidosis is influenced by the presence and severity of cardiac lesions. Thinning of the wall in the ventricular septum has often been reported, whereas an interventricular septal mass is rare. We describe a case of cardiac sarcoidosis resulting in a myocardial mass in the basal portion of the interventricular septum that was sensitive to corticosteroid treatment.

High on-treatment platelet reactivity (HTPR) has been reportedly associated with adverse ischemic events after coronary intervention. A recent study showed “thrombo-restenosis” pattern in restenotic lesions after coronary stent implantation by using optical coherence tomography. However, an