91-year-old Emperor Emeritus Akihito of Japan released from the hospital: Diagnosed with silent myocardial ischemia, will begin a new medication regimen

On May 10, 2025, Emperor Emeritus Akihito of Japan, accompanied by Empress Emerita Michiko of Japan, was discharged from the University of Tokyo Medical School Hospital in Tokyo and returned to the Sento Imperial Residence. He had been hospitalized for five days for a cardiac examination and was diagnosed with asymptomatic myocardial ischemia, a condition where the heart muscle doesn't receive enough blood flow. The medical team adjusted his treatment plan, adding new medication and recommending the avoidance of excessive exercise to slow down the progression of arteriosclerosis. Emperor Emeritus Akihito had previously undergone coronary artery bypass surgery in 2012 and was diagnosed with right heart failure in 2022, and he continues to receive treatment for this condition.

Detailed Condition and Diagnosis Process

Emperor Emeritus Akihito, now 91 years old, was initially suspected of having myocardial ischemia during a routine health check in April. After further examinations at his residence on May 4, doctors considered the likelihood of myocardial ischemia to be very high, leading to his hospitalization on May 6 for more detailed cardiac examinations.

During his hospital stay, Akihito underwent several cardiac tests, including an electrocardiogram, X-ray, cardiac ultrasound, and coronary computed tomography (CT) scan. The results showed that although Akihito himself did not experience any subjective discomfort, there was a significant insufficiency in myocardial blood flow under a certain level of exercise load. Based on this, the medical team diagnosed him with "Silent Myocardial Ischemia," a cardiovascular disease common in elderly patients and closely related to the progression of arteriosclerosis.

Treatment Plan and Lifestyle Adjustments

According to the Imperial Household Agency and the medical team, Akihito will add new medication to his existing treatment to inhibit the progression of arteriosclerosis and improve coronary blood flow. Doctors also recommended adjusting daily physical activities to avoid excessive exercise load.

Specifically, although Akihito currently has no obstacles in daily activities such as conversation and walking, the medical team pointed out that overall physical exertion could still put stress on the heart. Therefore, future evaluations will be made regarding his stair walking and muscle strength maintenance exercises at the Sento Imperial Palace, with adjustments made as necessary.

Medical Background and Past Medical History

Emperor Emeritus Akihito has faced cardiovascular issues before. As early as February 2012, he underwent coronary artery bypass surgery to treat myocardial ischemia due to arterial narrowing. This major cardiac surgery is typically used for patients with severe narrowing or calcification of multiple coronary arteries, restoring myocardial blood flow by bypassing the blocked areas with grafted vessels.

Additionally, in July 2022, Akihito was diagnosed with right heart failure during a cardiac MRI at the University of Tokyo Hospital. Since then, he has continued to receive internal medicine treatment and follow medical advice, including fluid intake restrictions, with his condition gradually stabilizing.

Medical Team and Imperial Household Agency Statement

In a statement on May 10, the Imperial Household Agency stated that Akihito currently experiences no symptoms and his daily life remains unaffected. After close coordination with the medical team, it was decided to strengthen medication treatment on the existing treatment basis and continue to monitor the condition's development. Doctors also emphasized that Akihito's heart condition will be monitored more cautiously than before.

On the day of discharge, Akihito and Empress Emerita Michiko expressed gratitude to the medical team. Reports indicate that Michiko visited daily since Akihito's hospitalization, providing stable support for his emotions and recovery.

Hospitalization and Discharge Situation

Akihito was hospitalized on May 6 and left the University of Tokyo Hospital around 11:30 a.m. on May 10, accompanied by Michiko, returning to the Sento Imperial Palace in the Akasaka area of Tokyo. This marked his first hospitalization since his coronary artery bypass surgery in 2012.

This hospitalization did not affect Akihito's daily life arrangements. The Imperial Household Agency noted that he will continue his research on goby fish, one of his long-standing academic interests.