Diagnostic Implications of Elevated Levels of Smooth-Muscle Myosin Heavy-Chain Protein in Acute Aortic Dissection: The Smooth Muscle Myosin Heavy Chain Study

3 October 2000 | Volume 133 Issue 7 | Pages 537-541

Background: A rapid 30-minute assay of circulating smooth-muscle myosin heavy-chain protein has been developed as a biochemical diagnostic tool for aortic dissection.

Objective: To determine the sensitivity and specificity of this assay.

Design: Cross-sectional study.

Setting: 8 major cardiovascular centers in Japan.

Patients: 95 patients with acute aortic dissection, 48 patients with acute myocardial infarction, and 131 healthy volunteers.

Measurements: Levels of circulating smooth-muscle myosin heavy-chain protein.

Results: Patients with acute aortic dissection who presented within 3 hours after onset had elevated levels of circulating smooth-muscle myosin heavy-chain protein. In these patients, the assay had a sensitivity of 90.9%, a specificity of 98% compared with healthy volunteers, and a specificity of 83% compared with patients who had acute myocardial infarction; the clinical decision limit was 2.5 µg/L. All patients with proximal lesions had elevated levels of smooth-muscle myosin heavy-chain protein, and only patients with distal lesions had decreased levels (<2.5 µg/L).

Conclusions: Levels of smooth-muscle myosin heavy-chain protein can be used to diagnose aortic dissection soon after symptom onset. The assay had the greatest diagnostic value in patients with proximal lesions.

Author and Article Information

From University of Tokyo, Tokyo Women's Medical University, Keio University, and Sakakibara Heart Institute, Tokyo; Gunma University, Gunma; Iwate Medical University, Iwate; Kagoshima University, Kagoshima; and Kokura Memorial Hospital, Kokurakita-ku, Japan.

Acknowledgments: The authors thank the diagnostics division of Yamasa Corp. for assistance in performing the assays.

Requests for Single Reprints: Toru Suzuki, MD, Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan; e-mail, torusuzu-tky{at}umin.ac.jp.

Current Author Addresses: Drs. Suzuki, Katoh, and Nagai: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.

Drs. Tsuchio, Hasegawa and Kurabayashi: Second Department of Internal Medicine, School of Medicine, Gunma University, 3-39-22 Showa-machi, Maebashi-shi, Gunma 371-8511, Japan.

Drs. Ohira and Hiramori: Second Department of Internal Medicine, School of Medicine, Iwate Medical University, 19-1 Uchimaru, Morioka-shi, Iwate 020-8505, Japan.

Drs. Sakomura and Kasanuki: Cardiology Department, Heart Institute of Japan, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan.

Drs. Hori and Aikawa: Department of Emergency and Critical Care Medicine, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582, Japan.

Drs. Abe and Tei: First Department of Internal Medicine, Faculty of Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima-shi, Kagoshima 890-8520, Japan.

Drs. Nakagawa and Nobuyoshi: Department of Cardiology, Kokura Memorial Hospital, 1-1 Kifune-machi, Kokurakita-ku, Kitakyushu 802-8555, Japan.

Drs. Misu and Sumiyoshi: Department of Cardiology, Sakakibara Heart Institute, 2-5-4 Yoyogi, Shibuya-ku, Tokyo 151-0053, Japan.

Author Contributions: Conception and design: T. Suzuki, H. Katoh, R. Nagai.

Analysis and interpretation of the data: T. Suzuki, H. Katoh, R. Nagai.

Drafting of the article: T. Suzuki, H. Katoh, R. Nagai.

Critical revision of the article for important intellectual content: T. Suzuki, H. Katoh, R. Nagai.

Final approval of the article: T. Suzuki, H. Katoh, R. Nagai, Y. Tsuchio, A. Hasegawa, M. Kurabayashi, A. Ohira, K. Hiramori, Y. Sakomura, H. Kasanuki, S. Hori, N. Aikawa, S. Abe, C. Tei, Y. Nakagawa, M. Nobuyoshi, K. Misu, T. Sumiyoshi.

Provision of study materials or patients: T. Suzuki, H. Katoh, R. Nagai, Y. Tsuchio, A. Hasegawa, M. Kurabayashi, A. Ohira, K. Hiramori, Y. Sakomura, H. Kasanuki, S. Hori, N. Aikawa, S. Abe, C. Tei, Y. Nakagawa, M. Nobuyoshi, K. Misu, T. Sumiyoshi.

Statistical expertise: T. Suzuki, H. Katoh, R. Nagai.

Obtaining of funding: T. Suzuki, H. Katoh, R. Nagai.

Administrative, technical, or logistic support: T. Suzuki, H. Katoh, R. Nagai.

Collection and assembly of data: T. Suzuki, H. Katoh, R. Nagai, Y. Tsuchio, M. Kurabayashi, A. Ohira, K. Hiramori, Y. Sakomura, H. Kasanuki, S. Hori, N. Aikawa, S. Abe, C. Tei, Y. Nakagawa, M. Nobuyoshi, K. Misu, T. Sumiyoshi.