<strong>Introduction</strong>: Cardiac myxomas represent the most frequent forms of primary tumors of the heart. The most frequent location is the interatrial septum. We report the clinical case of a myxom...<strong>Introduction</strong>: Cardiac myxomas represent the most frequent forms of primary tumors of the heart. The most frequent location is the interatrial septum. We report the clinical case of a myxoma of the left atrium and discuss its epidemiological and therapeutic aspects through a review of the literature. <strong>Observation</strong>: This was a 41-year-old female patient who presented with sudden rotational dizziness associated with vomiting. MRI revealed multiple punctiform bilateral supra and subtentorial strokes of different ages, recent and semi-recent, suggesting an embologenic etiology. Transesophageal echocardiography found a large pedunculated, homogeneous, avascular tumor hanging from the interatrial septum. The patient is operated on urgently under cardiopulmonary bypass for resection of a large tumor located in the left atrium. The pathological examination concluded with the diagnosis of myxoma of the left atrium. The postoperative follow-up was straightforward and the patient was discharged from the hospital via home hospitalization. <strong>Conclusion</strong>: The diagnosis of cardiac myxomas is suspected in the presence of symptoms associated with echocardiographic images of intracardiac masses and confirmed by histological study. Embolic accidents are one of the formidable complications of myxomas. Surgical management is urgent, especially in the presence of predictive morphological features of embolism on echocardiography.展开更多
在对57例受检者实施食管心房调搏过程中,分别在 P 波呈向下、双向及向上3种波形情况下固定电极进行起搏,以探讨最佳起搏部位。发现起搏成功率(依次为87.72%、82.46%、91.23%)及起搏阈值(依次为24.83±4.82,24.07±5.44,23.91...在对57例受检者实施食管心房调搏过程中,分别在 P 波呈向下、双向及向上3种波形情况下固定电极进行起搏,以探讨最佳起搏部位。发现起搏成功率(依次为87.72%、82.46%、91.23%)及起搏阈值(依次为24.83±4.82,24.07±5.44,23.91±4.24 V)分别相互进行比较,差异无显著性。进而固定起搏阈值20 V,在食管电极插入过程中记录到 P 波后,边起搏边调整电极位置,所有病例均能成功起搏,且3种 P 波出现机率相等。表明起搏阈值与心电图波形无关,只要食管导联记录到 P 波便可起搏,不必强求一定波形。展开更多
目的通过对快速心房起搏犬的电生理特性、收缩功能及超微结构的研究,观察短时间快速心房电活动是否可引起心房重构,并探讨其在房颤持续中的作用。方法健康杂种犬17只。实验组12只,经右心耳起搏450次/min,持续5小时。快速心房刺激前后分...目的通过对快速心房起搏犬的电生理特性、收缩功能及超微结构的研究,观察短时间快速心房电活动是否可引起心房重构,并探讨其在房颤持续中的作用。方法健康杂种犬17只。实验组12只,经右心耳起搏450次/min,持续5小时。快速心房刺激前后分别测量 P 波时程及心房有效不应期,并用多普勒超声评价二尖瓣前向血流变化。实验结束后取左心耳及梳状肌组织观察其超微结构。对照组5只,插入电极但不起搏,与实验组同步行各项检查。结果持续快速刺激5小时后,实验组心房有效不应期降低,P 波时程增加;二尖瓣心房收缩期血流速度降低了17%;检查发现部分心肌细胞出现肌原纤维的损失、糖原累积及线粒体大小及形状的改变;而对照组均未发现明显变化。结论短时间快速心房电活动可导致犬心房发生电重构、收缩重构及结构重构,而心房结构重构可能是心房发生电重构和收缩重构的原因之一。展开更多
文摘<strong>Introduction</strong>: Cardiac myxomas represent the most frequent forms of primary tumors of the heart. The most frequent location is the interatrial septum. We report the clinical case of a myxoma of the left atrium and discuss its epidemiological and therapeutic aspects through a review of the literature. <strong>Observation</strong>: This was a 41-year-old female patient who presented with sudden rotational dizziness associated with vomiting. MRI revealed multiple punctiform bilateral supra and subtentorial strokes of different ages, recent and semi-recent, suggesting an embologenic etiology. Transesophageal echocardiography found a large pedunculated, homogeneous, avascular tumor hanging from the interatrial septum. The patient is operated on urgently under cardiopulmonary bypass for resection of a large tumor located in the left atrium. The pathological examination concluded with the diagnosis of myxoma of the left atrium. The postoperative follow-up was straightforward and the patient was discharged from the hospital via home hospitalization. <strong>Conclusion</strong>: The diagnosis of cardiac myxomas is suspected in the presence of symptoms associated with echocardiographic images of intracardiac masses and confirmed by histological study. Embolic accidents are one of the formidable complications of myxomas. Surgical management is urgent, especially in the presence of predictive morphological features of embolism on echocardiography.
文摘在对57例受检者实施食管心房调搏过程中,分别在 P 波呈向下、双向及向上3种波形情况下固定电极进行起搏,以探讨最佳起搏部位。发现起搏成功率(依次为87.72%、82.46%、91.23%)及起搏阈值(依次为24.83±4.82,24.07±5.44,23.91±4.24 V)分别相互进行比较,差异无显著性。进而固定起搏阈值20 V,在食管电极插入过程中记录到 P 波后,边起搏边调整电极位置,所有病例均能成功起搏,且3种 P 波出现机率相等。表明起搏阈值与心电图波形无关,只要食管导联记录到 P 波便可起搏,不必强求一定波形。
文摘目的通过对快速心房起搏犬的电生理特性、收缩功能及超微结构的研究,观察短时间快速心房电活动是否可引起心房重构,并探讨其在房颤持续中的作用。方法健康杂种犬17只。实验组12只,经右心耳起搏450次/min,持续5小时。快速心房刺激前后分别测量 P 波时程及心房有效不应期,并用多普勒超声评价二尖瓣前向血流变化。实验结束后取左心耳及梳状肌组织观察其超微结构。对照组5只,插入电极但不起搏,与实验组同步行各项检查。结果持续快速刺激5小时后,实验组心房有效不应期降低,P 波时程增加;二尖瓣心房收缩期血流速度降低了17%;检查发现部分心肌细胞出现肌原纤维的损失、糖原累积及线粒体大小及形状的改变;而对照组均未发现明显变化。结论短时间快速心房电活动可导致犬心房发生电重构、收缩重构及结构重构,而心房结构重构可能是心房发生电重构和收缩重构的原因之一。
