Background: Secondary amenorrhea, defined as the absence of menstruation for three or more consecutive months in women with previously regular cycles, has a broad differential diagnosis that includes endocrine, metabolic, psychosocial, and systemic causes. Heart failure (HF) is a multisystem syndrome that may alter neurohormonal signaling and physiologic stress responses, creating a biologically plausible context for menstrual disturbance. We report a case in which menstrual function resumed after treatment and clinical stabilization of HF. Case Report: A 25-year-old female with a two-year history of secondary amenorrhea presented with exertional dyspnea, orthopnea, and bilateral lower extremity edema. Physical examination showed elevated jugular venous pressure and a systolic murmur. Echocardiography demonstrated mildly reduced left ventricular ejection fraction (44%), dextrocardia, left atrial enlargement, and moderate mitral regurgitation. She was diagnosed with congestive heart failure and treated with intravenous diuretics followed by guideline-directed medical therapy (beta-blocker, angiotensin-converting enzyme inhibitor, and mineralocorticoid receptor antagonist). Her symptoms improved clinically, and by the third month of follow-up she reported return of menstruation, with continued regular cycles during 9 months of follow-up. Conclusion: This case demonstrates a temporal association between HF treatment/clinical improvement and resolution of secondary amenorrhea, but it does not establish causality. The observation is hypothesis-generating and should be interpreted in the context of an incomplete endocrine-gynecologic etiologic evaluation and the absence of serial hormonal measurements. Nevertheless, the case supports clinical awareness of menstrual health in women with HF and motivates prospective studies using standardized reproductive and cardiovascular assessments to clarify mechanisms and determine whether this association is reproducible.
