本文讨论罕见的心脏疾病病例，患者因持续1个月以上的反复发热及伴随头晕、乏力等症状入院就诊。其病史中包括晕厥事件、高血压病以及运动后晕倒的频繁发生。通过一系列的临床检查和影像学检查，包括心脏超声、胸部CT以及血液和骨髓培养，患者最终确诊为二尖瓣副瓣(AMVT)伴隐匿性左室流出道梗阻(LVOTO)。该病例的独特之处在于患者的症状与AMVT的静息状态下无关，而是在运动后才出现，这对于及时明确诊断和治疗提出了挑战。通过手术干预，患者得到了有效治疗，且术后随访结果正常。这个案例强调了在面对不明原因晕厥的患者时，应充分结合病史和运动激发的超声心动图检查，以明确是否存在隐匿性LVOTO，有助于准确评估病情并制定正确的诊断和治疗方案。此外，还需要注意与感染性心内膜炎和其他心脏疾病进行鉴别诊断，以排除其他可能性。

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