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Ectopic excitability in pulmonary veins (PVs) is the major cause of atrial fibrillation. We previously reported that the inositol trisphosphate receptor in rat PV cardiomyocytes cooperates with the Na+-Ca2+ exchanger to provoke ectopic automaticity in response to norepinephrine. Here, we focused on adenylyl cyclase (AC) as another effector of norepinephrine stimulation. RT-PCR, immunohistochemistry, and Western blotting revealed that the abundant expression of Ca2+-stimulable AC3 was restricted to the supraventricular area, including the PVs. All the other AC isotypes hardly displayed any region-specific expressions. Immunostaining of isolated cardiomyocytes showed an enriched expression of AC3 along the t-tubules in PV myocytes. The cAMP-dependent response of L-type Ca2+ currents in the PV and LA cells is strengthened by the 0.1 mM intracellular Ca2+ condition, unlike in the ventricular cells. The norepinephrine-induced automaticity of PV cardiomyocytes was reversibly suppressed by 100 µM SQ22536, an adenine-like AC inhibitor. These findings suggest that the specific expression of AC3 along t-tubules may contribute to arrhythmogenic automaticity in rat PV cardiomyocytes. [ABSTRACT FROM AUTHOR]

Open thoracic aortic surgery is believed to necessitate more intensive rehabilitation. This study aimed to compare the progress of postoperative rehabilitation between standard and delayed mobilization. A retrospective review was conducted on 199 patients who underwent isolated total aortic arch replacement via median sternotomy. Cases of in-hospital mortality and postoperative stroke were excluded. Based on the current guidelines for cardiovascular rehabilitation of the Japanese Circulation Society, patients were categorized into standard mobilization (could sit on the edge of bed within 2 days) and delayed mobilization (could not do so) groups. Rehabilitation progress was compared among both groups. Initial mobilization was delayed in 100 patients (delayed mobilization group), primarily because of respiratory failure (46.0%). Preoperative risk characteristics, including EuroSCORE II (median, 2.9 versus 3.5), were similar between the standard and delayed mobilization groups. The delayed mobilization group had longer operation (median, 6.1 versus 8.0 hours, P < 0.001) and cardiopulmonary bypass (median, 3.2 versus 4.1 hours, P < 0.001) times. Independent ambulation occurred earlier in the standard mobilization group (median, 6.0 versus 8.0 days, P < 0.001).In conclusion, early initiation of sitting on the edge of the bed within 2 days was associated with earlier independent ambulation during postoperative rehabilitation, which supports the current guidelines. Longer operation and cardiopulmonary bypass times were associated with delayed mobilization initiation, suggesting the need for more tailored approaches in such cases.

Background: Acute aortic dissection (AAD) is a life-threatening condition that imposes a significant socioeconomic burden on society. The Tohoku Registry of Acute Aortic Dissection (TRAD) is a collaboration of 13 tertiary referral hospitals in the Tohoku region of Japan designed to investigate all aspects of AAD treatment in this district, and to address significant clinical questions to help understand its dynamic pathology and develop optimal strategies for treating AAD., Methods and Results: Comprehensive cases developing type A and type B AAD, including those with prehospital cardiopulmonary arrest transported to TRAD centers, over 5 years from 2017 to 2022 are registered. The TRAD dataset encompasses prehospital information, diagnostic imaging findings, treatment modalities, and outcomes for each case. After discharge, patients will be followed up for 10 years for survival, aortic events and inspection data., Conclusions: We believe that this multicenter registry of AAD analyses will clarify the current short-term outcomes of recent surgical, endovascular, and medical treatments in the Tohoku region, and provide insights into the long-term outcomes of different treatment modalities to achieve extended life expectancy in reasonably good health., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2024, THE JAPANESE CIRCULATION SOCIETY.)