Echocardiography|Research Team


Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine

Department of Cardiovascular Biology and Medicine,
Juntendo University Graduate School of Medicine

Specially Appointed Associate Professor Sakiko Miyazaki

Using echocardiography for early detection of cardiac dysfunction in cancer patients due to anti-cancer drugs.

Echocardiography is one of the most commonly used tests for diagnosing heart diseases because it is non-invasive and can be performed repeatedly. Observation of moving images in 3D has become commonplace, and this type of imaging is becoming increasingly important as a diagnostic imaging technique. In spite of the remarkable development in diagnostic equipment, there are only a limited number of doctors who currently specialize in it. Fascinated by the possibilities of ultrasonography, Dr. Sakiko Miyazaki is working in cooperation with various departments for early-stage detection and diagnosis of cardiovascular complications associated with complex heart diseases and systemic diseases.

Interest in echocardiography technique led to a strong desire for research

After graduating from medical school, I underwent initial training at the Japanese Red Cross Medical Center located in Hiroo. At the time of the training, I had not yet decided to pursue the field of cardiovascular medicine. However, by repeatedly seeing how patients in critical condition brought to the hospital by ambulance were discharged with a smile, I began to feel that cardiovascular medical treatment is very worthwhile and appealing. Although it is interesting to treat diseases over an extended period of time, I was very attracted to the fact that I can experience the effects of treatment from day to day. My superior at the time recommended that the field of cardiovascular medicine would suit me, so I chose to pursue this field.

After joining the Department of Cardiovascular Medicine of Juntendo Clinic, I was assigned to Juntendo University Shizuoka Hospital, which also provides tertiary emergency care, and gained clinical experience there. Ever since then, I have been interested in echocardiography; however, Juntendo University did not have a doctor specializing in echocardiography at that time. Thereafter, Dr. Masao Daimon (currently with the University of Tokyo), who is a leading authority in the field of echocardiography in Japan, was appointed as head of the echocardiography team. I thought this was a unique opportunity for me to study echocardiography, so I decided to go on to graduate school and study echocardiography under Dr. Daimon.

It has been more than 10 years since I started researching ultrasound using echocardiography. Initially, I mainly studied cardiac valvular disease, and in my bachelor's thesis also I studied aortic stenosis. Thereafter, while studying in Italy, I researched the role of echocardiography during catheter treatment for aortic valve stenosis and published my findings in a paper. However, after returning to Japan, my interests and research targets were no longer limited to valvular disease, but also came to include various cardiomyopathy, congenital heart disease, and cancer patients who undergo cardiotoxic chemotherapy.

Possibility of early diagnosis of cardiac dysfunction associated with cancer treatment by using echocardiography

Although cancer is rarely treated in cardiovascular medicine, it is not uncommon for patients with breast cancer, hematological malignancies, and lung cancer, etc. to experience heart failure when using anticancer drugs. Early detection and appropriate treatment are required to avoid situations where the cancer is cured but the heart has deteriorated. Conducting research on the early diagnosis of cardiovascular complications caused by cancer treatment is one of initiatives that I am working on with the utmost enthusiasm at the moment.

I would like to participate in large-scale international multicenter research and connect it to daily clinical practice

Most recently, I have been participating in an international joint research on whether echocardiographic evaluation of cardiac function by using speckle tracking is useful for early detection and early treatment of cardiotoxicity in breast cancer patients treated with cancer drugs (SUCCOUR trial). The other day, an interim report of this study was accepted by JACC (a major academic journal in the field of circulatory organs). Since such large-scale research that attracts international attention cannot be conducted at one facility, I would like to eagerly participate in joint research with other facilities and to be proactively involved in initiatives that affect daily clinical practice.

If such research outcomes are reflected in the guidelines and the number of facilities following the standardized pattern increases, I believe that the level of medical care for cardiovascular complications associated with cancer may be enhanced overall rather than at individual facilities. Over the last few years, many Japanese researchers have won awards at international echocardiography conferences. I feel that research presentations made by Japanese researchers are drawing much attention.

The joy of overcoming difficulties in collaboration with laboratory technicians and doctors from other departments

All scientific and medical research has standard methods and echocardiography research is also carried out accordingly. Nonetheless, echocardiography research uses images taken by the laboratory technicians with an ultrasound device; therefore, the results are dependent on the technique of ultrasound technicians. In producing reliable results, apart from the ideas of researchers, it is important to ensure that the technicians of the facilities participating in the research have stable and high-quality skills.
Just as surgery depends on the skill of the surgeon, echocardiography also requires research that takes into account reproducibility and leads to the same direction at all hospitals, which make it difficult as well as interesting.

Congenital heart disease is the most difficult disease to diagnose with echocardiography. It is even more complicated after surgery. Once a month, doctors of cardiac surgery, cardiovascular medicine and pediatric cardiology, as well as ultrasound technicians meet to discuss the cases.
Furthermore, there are many opportunities for collaboration with clinical departments in addition to the cardiovascular department, such as pulmonary hypertension associated with collagen disease and cardiac amyloidosis associated with blood diseases, contributing to the endless research topics on echocardiography. In collaboration with the Department of Neurology, the diagnosis and treatment of cerebral infarction of unknown embolism source have recently drawn much attention, and we are actively performing examinations by using transesophageal echocardiography.

The physiology laboratory of our hospital is equipped with roughly 10 latest ultrasound machines from different manufacturers, and examinations are performed in collaboration with trained technicians. As an overwhelmingly large number of cases of ultrasound examinations are being carried out at Juntendo University Hospital, we are proud of being able to acquire a wide range of in-depth techniques and conduct research based thereon.

Doctor's experience and high level of expertise are the key to final diagnosis

Presently, with regard to ultrasonic diagnostic imaging equipment, several manufacturers in Japan and overseas are developing 3D and image analysis software with their respective unique features. 3D has become an easily accessible technology, and recently the image quality has improved to the extent that it is comparable to the images in the surgical field seen by surgeons during surgery.
Due to the outbreak of COVID-19 pandemic, doctors and technicians are avoiding examinations that require long-term contact with patients. The time may come in the future when all image analysis will be automated and examinations are conducted within a short time. Technologies using 3D, automation, and AI have the potential to develop significantly in the future, and there is still plenty of room for growth leading into the future.
Even with automation, the final diagnosis requires the experience of doctors. There are still only a limited number of doctors who specialize in echocardiography across Japan. I believe having echocardiography specialists will become even more important in the future.

Sakiko Miyazaki

Sakiko Miyazaki

2000 Graduated from Juntendo University School of Medicine. 2011 Doctor of Medicine, Juntendo University Graduate School of Medicine. 2012 Master of Public Health, the University of Tokyo.
Area of specialization is cardiovascular diagnostic imaging (Certified Specialist of The Japan Society of Ultrasonics in Medicine)