Heart failure is a critical global public health issue, significantly impacting patients' quality of life and healthcare costs. In Japan, heart diseases rank among the leading causes of death, highlighting the urgent need for effective treatment strategies for heart failure patients. In recent years, guideline-directed medical therapy (GDMT) has been increasingly recommended, with particular focus on the use and optimization of specific therapeutic agents. Our study demonstrated that the reinforcement of GDMT in heart failure patients receiving pimobendan may contribute to a reduction in rehospitalization rates. This effect was particularly pronounced in patients with reduced ejection fraction (rEF), emphasizing the pivotal role of GDMT in heart failure management. This article explores the impact of the combination of pimobendan and GDMT on the prognosis of patients with heart failure.

A 6-year-old boy was referred to us after an abnormal shadow was detected in the left upper lung field on a chest X-ray taken as part of a school cardiac screening program. We suspected an intrathoracic lipoblastoma on the basis of blood test results and CT, MRI, and other imaging findings, and we performed a surgical resection for diagnostic and therapeutic purposes. The pathological diagnosis was also lipoblastoma, and two years have passed without any postoperative complications. Lipoblastoma is a relatively rare benign tumor that is most commonly found on the trunk and extremities of infants, but cases like this one of a lipoblastoma in the thoracic cavity are extremely rare.

Carnitine is abundant in red meat, especially in lean cuts, and promotes energy metabolism through β-oxidation. Carnitine deficiency can lead to hypoglycemia. Here, we report two cases of severe hypoglycemia resulting from carnitine deficiency.

Case 1: The patient was a 4-year-old boy with a history of selective eating, characterized by a preference for white rice and a dislike of meat and vegetables. He had viral bronchitis, which led to a loss of appetite. He then required emergency admission to the hospital for seizures. On arrival, his blood glucose and free carnitine levels were 15 mg/dL and 6.0 μmol/L, respectively, and carnitine deficiency was diagnosed.

Case 2: The patient was a 4-year-old girl with poor appetite and a history of depressive episodes caused by an inability to finish meals, although she had no history of developmental problems. She had been hospitalized four times previously because of vomiting and poor food intake. When she was admitted for the fifth time, her free carnitine level was 17.5 μmol/L, and carnitine deficiency was diagnosed. Testing revealed no congenital metabolic disorders; therefore, carnitine deficiency was attributed to food selectivity and reduced dietary intake.

Various cases of secondary carnitine deficiency related to tube feeding, valproic acid, and antibacterial agents containing pivoxel have been reported; however, only two reports of carnitine deficiency due to food selectivity have been published, both of which were caused by an extremely unbalanced diet associated with neurodevelopmental disorders. However, when recurrent hypoglycemia is encountered, serum free carnitine levels should be measured and carnitine supplementation be considered even in the absence of a history of neurodevelopmental disorders.