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Coronary Artery Fistulas (CAF) are inappropriate connections between a coronary artery and a major vessel or a cardiac chamber. These fistulas may or may not present with symptoms, but they need to be detected as early as possible in order to decide the most appropriate treatment methodology (i.e. surgery vs. conservative management). We report the case of a 67-year-old female with no modifiable cardiovascular risk factors who had an unwitnessed sudden death at home during her ongoing evaluation of a fistula detected incidentally between the Left Anterior Descending Artery (LAD) and the Pulmonary Artery (PA). This case highlights that early diagnosis and treatment of symptomatic CAF are crucial to minimize the risk of sudden cardiac death. Although the symptomatic fistula of LAD to PA has been reported in the literature multiple times, it has been rarely reported that this fistula can result in sudden cardiac death.

Phase change materials (PCMs) have a large number of applications for thermal energy storage (TES) and temperature reduction in buildings due to their thermal characteristics and latent heat storage capabilities. The thermal mass of typical brick walls can be substantially increased using a suitable PCM primarily based on phase change temperature and heat of fusion for different weather conditions in summer and winter. This study proposed a novel dual-layer PCM configuration for brick walls to maintain human comfort for hot and cold climatic conditions in Islamabad, Pakistan. Numerical simulations were performed using Ansys Fluent for dual PCMs layered within a brick wall for June and January with melting temperatures of 29 °C and 13 °C. This study examined and discussed the charging and discharging cycles of PCMs over an extended period (one month) to establish whether the efficacy of PCMs is hindered due to difficulties in discharging. The results show that the combined use of both PCMs stated above provides better human comfort with reduced energy requirements in Islamabad throughout the year than using a single PCM (29 °C) for summer or winter (13 °C) alone.

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