Danvers, Mass., July 20, 2004 -- ABIOMED, Inc. (NASDAQ: ABMD) today announced that 47 of the 50 top hospitals for heart and heart surgery, as determined by U.S.News & World Report's 2004 survey of best hospitals, are ABIOMED customers. These leading heart centers all possess either the BVS® 5000 or AB5000™ Circulatory Support Systems, both of which are life-saving systems designed to provide temporary support while the natural heart rests and potentially recovers.

"ABIOMED has become a leader in acute circulatory support by providing heart recovery and assist systems that are versatile, reliable and allow for patient ambulation and transport," said Dr. Nicholas Smedira, Surgical Director of Cardiac Transplantation and Mechanical Circulatory Support at the Cleveland Clinic, ranked number one among heart hospitals in the U.S. News survey. "Among patients transferred to our facility from local cardiac centers, we have observed that the more stable the patient is on transfer, the more likely they are to recover. The success of acute circulatory support systems like the AB5000 may be predicated on early use following a cardiac event, and early transfer to advanced cardiac centers. We consider this kind of advanced, life-saving technology to be critical to our high standard for cardiac care."

About the BVS 5000 and AB5000:

• The BVS 5000 is the most widely used advanced cardiac assist system in the world, installed in more than 700 leading medical centers worldwide.
• The BVS 5000 is the most widely used advanced cardiac assist system in the world, installed in more than 700 leading medical centers worldwide.
• The AB5000 is ABIOMED's newest product offering, based on technology developed for the AbioCor Implantable Replacement Heart and approved by the FDA in 2003.
• The AB5000 Console is an advanced computer system with upgradeable software. It offers the flexibility of driving either the BVS 5000 blood pump or the AB5000 ventricle to support the left, right or both ventricles of the heart.
• In ongoing bench testing, the AB5000 Circulatory Support System has maintained performance exceeding 190 days of operation.
• Unlike other ventricular assist systems that can require multiple drivers for a single patient, patients on the AB5000 require only a single console - regardless of condition.
• The AB5000 is designed to allow patients to leave their hospital rooms and walk within the hospital and on hospital grounds. Multiple studies have shown that patient ambulation, or walking, greatly assists the recovery process.
• The ease of use and transport capability of the AB5000 System makes it an important option for both regional and local cardiac centers. Patients can be put on the AB5000 or the BVS 5000 System at their local hospital and then be transported to more advanced cardiac centers if necessary.

"We are proud to be the leader for bridge to recovery devices, and to partner with so many of the nation's leading heart care centers. Over the past twelve years, we've been able to save thousands of lives of individuals who would have died if they had not received temporary support for their hearts," commented Michael R. Minogue, CEO and President of ABIOMED. "We are committed to providing our surgeons and their patients with heart assist technologies that offer continually improved reliability, mobility, and ease of use to support their missions of clinical excellence."

The U.S.News & World Report survey evaluated all of 6,012 U.S. medical centers based on rigorous standards. Only 177, or fewer than 1 in 30, were of high-enough quality to be ranked in even a single specialty this year. The complete report is available online at http://www.usnews.com/ and in the July 12, 2004 printed edition.

The ranking model used by U.S. News was devised and is conducted by the National Opinion Research Center, a social science research group at the University of Chicago. Rankings for 12 of the 17 specialties are based on a combination of factors including number of procedures performed, key technologies, reputation and care-related factors, such as nursing. Rankings for five other specialties --- ophthalmology, pediatrics, psychiatry, rehabilitation and rheumatology -- are based on reputation alone.

Based in Danvers, Massachusetts, ABIOMED, Inc. (pronounced “AB’-EE-O-MED”) is a leading developer, manufacturer and marketer of medical products designed to assist or replace the pumping function of the failing heart. ABIOMED currently manufactures and sells the AB5000™ Circulatory Support System and the BVS® 5000 Biventricular Support System for the temporary support of all patients with failing but potentially recoverable hearts. The Company’s AbioCor® Implantable Replacement Heart is the subject of an initial clinical trial being conducted under an Investigational Device Exemption from the United States Food and Drug Administration. The AbioCor has not been approved for commercial distribution, and is not available for use or sale outside of the initial clinical trial.

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Media Contact:
Andrea tenBroek
Communications Specialist
(978) 646-1419
mediarelations@abiomed.com

Investor Relations Contact:
Edward E. Berger, Ph.D.
Vice President for Policy, Reimbursement and External Relations
(978) 646-1411
ir@abiomed.com