About this research group

Message from the Chairperson and Co-Chairs

Representative of the Japanese Society for Coronary Microcirculatory Disorders (J-CMD)
Professor and Head of the Department of Cardiovascular Medicine, Graduate School of Life Sciences,
Kumamoto University
Kenichi Tsujita

I am pleased to announce that I have been appointed as the Chair of the Japan Society for Coronary Microcirculatory Disorders (J-CMD). I am deeply honored to succeed Dr. Hiroaki Shimokawa, who has led this society to date, and to assume this important responsibility; at the same time, I feel a deep sense of duty and commitment.

Under the outstanding leadership of Dr. Shimokawa, this research group has worked to raise awareness of the importance of coronary microvascular dysfunction (CMD) both domestically and internationally, and has been advancing the establishment of a nationwide clinical network and research infrastructure. In recent years, CMD has garnered international attention as a key pathophysiological mechanism in ischemic heart disease, and there is a strong demand for a deeper understanding of CMD in the diagnosis and treatment of INOCA and microvascular angina. Furthermore, the number of facilities performing CMD testing in Japan has been steadily increasing, and the activities of this research group have expanded significantly, including through multicenter and international collaborative studies.

Serving as the chairperson during such a critical time is a great responsibility, but I intend to devote myself to the further development of this research group while continuing to seek guidance from Professor Shimokawa as co-chair.

Moving forward, J-CMD’s activities will focus on:

・Promoting multicenter collaborative research aimed at elucidating the pathophysiology of CMD and generating evidence

・Standardizing the diagnosis and treatment of CMD and disseminating these practices to clinical settings

・Fostering the development of young researchers and clinicians

・Promoting global academic exchange, including international collaborative research

Through these efforts, we aim to share evidence originating from Japan with the world.

Coronary microcirculatory dysfunction is a condition that has not been sufficiently visualized to date, and it represents one of the most critical areas of focus in future cardiovascular medicine. We are committed to working closely with the organizing committee and all participating institutions to ensure that this study group serves as a hub for research, clinical care, and education regarding CMD, thereby contributing to the improvement of patient care.

We sincerely appreciate your continued guidance and support.

April 2026

Co-Representative of the Japan Cerebral Microcirculation Disorder Research Society (J-CMD)
Professor Emeritus at Tohoku University
Specially Appointed Professor at International University of Health and Welfare
Hiroaki Shimokawa

As co-chair of the Japanese Association of Coronary Microvascular Dysfunction (J-CMD), I would like to extend my greetings.

Regarding coronary artery spasm, a key factor in the pathogenesis of ischemic heart disease in the Japanese population, I served as the representative and, with funding from the Japan Heart Foundation, conducted the academic activities of the “Coronary Spasm Study Group” for a total of 15 years (three five-year terms) from 2006 to 2021. This study group involved 85 institutions nationwide and conducted nationwide registry studies, among other initiatives, resulting in active academic activities such as the publication of numerous papers (1–8) and presentations at academic conferences.

Internationally, in 2012, ten researchers with an interest in coronary vasomotor disorders established the international collaborative research organization “Coronary Vasomotor Disorders International Study Group, COVADIS” (URL: https://covadis.online/), and I have participated in its activities as one of the founding members (9–18). This group also proposed diagnostic criteria for microvascular angina (MVA) (15).

Among the 10 founding members are Professor Filippo Crea, who currently serves as Editor-in-Chief of the *European Heart Journal*, and Professor Paolo Camici, Editor-in-Chief of the *International Journal of Cardiology*.

Ischemic heart disease is classified into acute coronary syndrome (ACS) and chronic coronary syndrome (CCS). The mechanisms underlying CCS include: (1) stenosis or occlusion of large coronary arteries, (2) spasm of large coronary arteries, and (3) impaired coronary microcirculation (Figures 1 and 2). Mechanisms ② and ③ are collectively referred to as Ischemia with No Obstructive Coronary Artery Disease (INOCA) (Figure 3). Furthermore, it is important to note that these three mechanisms coexist in the same patient in varying proportions (Figure 3). Additionally, the causes of coronary microcirculatory dysfunction include two mechanisms: increased contractility and decreased dilation of the coronary microvasculature (Figure 4). Our research has revealed that these two mechanisms also coexist in the same patient in varying proportions (Figure 5). Crucially, the prognosis is worst when these coronary functional abnormalities occur in both the large coronary arteries and the coronary microvasculature (Figure 6).

From 2015 to 2019, I served as the principal investigator of a multicenter prospective registry study on microvascular angina (MVA), involving 14 centers across seven countries, primarily centered around the COVADIS center (Figure 7). The results revealed that MVA patients enrolled according to the strict diagnostic criteria of COVADIS experienced major cardiovascular events (MACE)—primarily unstable angina—at an annual rate of 7.7%. Furthermore, after adjusting for clinical background, it became clear that MVA is a significant condition with no gender or racial differences in long-term prognosis (1,10). This result was comparable to the annual incidence of MACE (approximately 5%) in patients with coronary artery disease reported in the ISCHEMIA Study, published in the NEJM in 2000 (Figure 8). In response, the European Society of Cardiology (ESC) issued a press release concurrent with the publication of this paper, stating that “microcirculatory dysfunction of the coronary arteries is a significant global health issue” (Figure 9).

As noted above, while the importance of coronary microcirculatory dysfunction is gaining global recognition, awareness of it in clinical practice remains insufficient. In Japan, testing for coronary microcirculatory dysfunction is currently available only at a limited number of facilities, and it is believed that many patients across the country are suffering without receiving a proper diagnosis.

Against this medical and social backdrop, in August 2022, we reorganized the “Coronary Spasm Study Group” into the “Japan Coronary Microcirculation Disorder Study Group” to further advance our research and raise awareness of this condition within the medical community and the general public.

Starting in fiscal year 2026, we will pass the baton to Professor Kenichi Tsujita of the Department of Cardiology at Kumamoto University as the new Chairperson, and the secretariat will also be transferred to the Department of Cardiology at Kumamoto University. I will remain as Co-Chair and continue to contribute to the activities of this Society.

We sincerely ask for your continued support.

April 2026

Research Paper Presented by the Coronary Spasm Research Group

1.Shimokawa H, Suda A, Takahashi J, Berry C, Camici PG, Crea F, Escaned J, Ford T, Yii E, Kaski JC, Kiyooka T, Mehta PK, Ong P, Ozaki Y, Pepine C, Rimoldi O, Safdar B, Sechtem U, Tsujita K, Yasuda S, Beltrame JF, Merz CNB; the Coronary Vasomotor Disorders International Study (COVADIS) Group. Clinical characteristics and prognosis of patients with microvascular angina -An international and prospective cohort study by the Coronary Vasomotor Disorders International Study (COVADIS) Group-　Eur Heart J. 2021;42: 4592-4600.

2.Mori H, Takahashi J, Sato K, Miyata S, Takagi Y, Tsunoda R, Sumiyoshi T, Matsui M, Tanabe Y, Sueda S, Momomura S, Kaikita K, Yasuda S, Ogawa H, Shimokawa H, Suzuki H; Japanese Coronary Spasm Association. The impact of antiplatelet therapy on patients with vasospastic angina: A multicenter registry study of the Japanese Coronary Spasm Association. Int J Cardiol Heart Vasc. 2020 Jun 9;29:100561. doi: 10.1016/j.ijcha.2020.100561.

3.Sato K, Takahashi J, Odaka Y, Suda A, Sueda S, Teragawa H, Ishii K, Kiyooka T, Hirayama A, Sumiyoshi T, Tanabe Y, Kimura K, Kaikita K, Ong P, Sechtem U, Camici PG, Kaski JC, Crea F, Beltrame JF, Shimokawa H; Japanese Coronary Spasm Association. Clinical characteristics and long-term prognosis of contemporary patients with vasospastic angina: Ethnic differences detected in an international comparative study. Int J Cardiol. 2019;291:13-18.

4.Takahashi J, Nihei T, Takagi Y, Miyata S, Odaka Y, Tsunoda R, Seki A, Sumiyoshi T, Matsui M, Goto T, Tanabe Y, Sueda S, Momomura S, Yasuda S, Ogawa H, Shimokawa H; Japanese Coronary Spasm Association. Prognostic impact of chronic nitrate therapy in patients with vasospastic angina: multicenter registry study of the Japanese coronary spasm association. Eur Heart J. 2015;36:228-37.

5.Takagi Y, Takahashi J, Yasuda S, Miyata S, Tsunoda R, Ogata Y, Seki A, Sumiyoshi T, Matsui M, Goto T, Tanabe Y, Sueda S, Sato T, Ogawa S, Kubo N, Momomura S, Ogawa H, Shimokawa H; Japanese Coronary Spasm Association. Prognostic stratification of patients with vasospastic angina: a comprehensive clinical risk score developed by the Japanese Coronary Spasm Association. J Am Coll Cardiol. 2013;62:1144-53.

6.Kawana A, Takahashi J, Takagi Y, Yasuda S, Sakata Y, Tsunoda R, Ogata Y, Seki A, Sumiyoshi T, Matsui M, Goto T, Tanabe Y, Sueda S, Kubo N, Momomura S, Ogawa H, Shimokawa H; Japanese Coronary Spasm Association. Gender diff erences in the clinical characteristics and outcomes of patients with vasospastic angina. Circ J. 2013;77:1267-74.

7.Takagi Y, Yasuda S, Takahashi J, Tsunoda R, Ogata Y, Seki A, Sumiyoshi T, Matsui M, Goto T, Tanabe Y, Sueda S, Sato T, Ogawa S, Kubo N, Momomura S, Ogawa H, Shimokawa H; Japanese Coronary Spasm Association. Clinical implications of provocation tests for coronary artery spasm: safety, arrhythmic complications, and prognostic impact: Multicentre Registry Study of the Japanese Coronary Spasm Association. Eur Heart J 2013;34:258-67.

8.Takagi Y, Yasuda S, Tsunoda R, Ogata Y, Seki A, Sumiyoshi T, Matsui M, Goto T, Tanabe Y, Sueda S, Sato T, Ogawa S, Kubo N, Momomura S, Ogawa H, Shimokawa H; Japanese Coronary Spasm Association. Clinical characteristics and long-term prognosis of vasospastic angina patients who survived out-of hospital cardiac arrest: multicenter registry study of the Japanese Coronary Spasm Association. Circ Arrhythm Electrophysiol 2011;4:295-302.

Research paper published by COVADIS

9.Bairey Merz CN, Beltrame JF, Berry C, Boden WE, Camici PE, Crea F, Hochman JS, Kaski JC, O’Gara PT, Ong P, Pepine CJ, Shimokawa H, Sechtem U, Stone GW.
Insights to advance our management of myocardial ischemia: From obstructive epicardial disease to functional coronary alterations Am Heart J Plus. Published Online 8 October 2021.

10.Shimokawa H, Suda A, Takahashi J, Berry C, Camici PG, Crea FE, Ford T, Yii E, Kaski JC, Kiyooka T, Mehta PK, Ong P, Ozaki Y, Pepine C, Rimoldi O, Safdar B, Sechtem U, Tsujita K, Beltrame JF, Bairey Merz CN. Clinical characteristics and prognosis of patients with microvascular angina: an international and prospective cohort study by the Coronary Vasomotor Disorders International Study (COVADIS) Group Eur Heart J. 2021;42: 4592-4600.

11.Suda A, Takahashi J, Beltrame JF, Berry C, Camici PG, Crea F, Escaned J, Ford T, Carlos Kaski J, Kiyooka T, Metha PK, Ong P, Ozaki Y, Pepine C, Rimoldi O, Safdar B, Sechtem U, Tsujita K, Yii E, Bairey Merz CN, Shimokawa H. International prospective cohort study of microvascular angina – Rationale and design Int J Cardiol Heart Vasc. 2020 31:100630.

12.Ford TJ, Ong P, Sechtem U, Beltrame J, Camici PG, Crea F, Kaski JC, Bairey Merz CN, Pepine CJ, Shimokawa H, Berry C. Assessment of Vascular Dysfunction in Patients Without Obstructive Coronary Artery Disease: Why, How, and When. JACC Cardiovasc Interv JACC Cardiovasc Interv. 2020;13(16):1847-1864.

13.Crea F, Bairey Merz CN, Beltrame JF, Berry C, Camici PG, Kaski JC, Ong P, Pepine CJ, Sechtem U, Shimokawa H. Mechanisms and diagnostic evaluation of persistent or recurrent angina following percutaneous coronary revascularization Eur Heart J. 2019;40(29):2455-2462.

14.Ong P, Camici PG, Beltrame JF, Crea F, Shimokawa H, Sechtem U, Kaski JC, Bairey Merz CN, Coronary Vasomotion Disorders International Study Group (COVADIS). Response to letter from Picichè: The microvascular network connecting extracardiac arteries to the heart. Int J Cardiol. 2018 15;259:56.

15.Ong P, Camici PG, Beltrame JF, Crea F, Shimokawa H, Sechtem U, Kaski JC, Bairey Merz CN. Coronary Vasomotion Disorders International Study Group (COVADIS).
International standardization of diagnostic criteria for microvascular angina.
Int J Cardiol. 2018 250:16-20.

16.Beltrame JF, Crea F, Kaski JC, Ogawa H, Ong P, Sechtem U, Shimokawa H, Bairey Merz CN. The Who, What, Why, When, How and Where of Vasospastic Angina
Circ J. 2016 80 (2): 289-298.

17.Crea F, Bairey Merz CN, Beltrame JF, Kaski JC, Ogawa H, Ong P, Sechtem U, Shimokawa H, Camici PG. The parallel tales of microvascular angina and heart failure with preserved ejection fraction: a paradigm shift Eur Heart J. 2016;38 (7): 473–477.

18.Beltrame JF, Crea F, Kaski JC, Ogawa H, Ong P, Sechtem U, Shimokawa H, Bairey Merz CN, On Behalf of the Coronary Vasomotion Disorders International Study Group (COVADIS). International standardization of diagnostic criteria for vasospastic angina Eur Heart J. 2015;38 (33): 2565–2568.