What: The Ponce School of Medicine and the Agency for Toxic Substances and Disease Registry (ATSDR), a public health agency of the U.S. Dept. of Health and Human Services, today jointly are releasing the Summary Report for the Vieques Heart Study Expert Panel Review.

In January 2001, the government of Puerto Rico notified federal authorities about the results of a pilot study indicating possible abnormalities of heart valves and thickening of the pericardium (lining surrounding the heart) among some Vieques residents. The U.S. Dept. of Health and Human Services asked ATSDR to investigate the issues raised by the study. Concurrent with this request, the Ponce School of Medicine (PSM), led by President and Dean Dr. Manuel Martinez Maldonado, launched a more definitive study of possible heart abnormalities among Vieques fishermen.

In March 2001, ATSDR and PSM representatives agreed to jointly select a panel of independent experts to review and interpret the new study's findings and to independently re-read the study's echocardiograms. Eight accomplished physician-scientists were chosen as reviewers. The panelists were from research institutes and universities. Four were from the United States, two were from Mexico and two were from Spain. Half the panel members were experts in cardiology and echocardiography; the others were epidemiologists.

Because of its reputation and extensive experience, the echocardiography laboratory at the Mayo Clinic in Rochester, Minn., was chosen to review the study's echocardiograms.

In July 2001, the panel met in San Juan. Co-chairs of the meeting were Dr. Martinez Maldonado and Dr. David Fleming, ATSDR Deputy Administrator. The purpose of the meeting was to review the methods, results and public health significance of PSM's Vieques Heart Study, considering the echocardiography readings of both PSM and the Mayo Clinic.

Panel Findings: The panel found that the well-executed PSM study showed no indication of abnormal heart function attributable to pericardial thickening. Other observations included:

• By PSM's measurements, the average pericardial thickness was slightly greater among Vieques fishermen than among Ponce Playa fishermen (1.20 mm vs. 1.05 mm), and this difference was statistically significant.

• The values measured by the Mayo Clinic were within the same range as those measured by PSM, but they did not show a statistically significant difference between the Ponce and Vieques fishermen.

• The panel experts also concluded that the measurements of pericardial thickness made both by PSM and Mayo were similar and were all within the normal range. The small differences between Ponce and Mayo findings were attributed to the limited precision of the trans-thoracic echocardiography measurement technique. Although a small average difference between the Vieques fishermen and control groups could not be ruled out with certainty, the panel experts observed that no subject showed any indication of abnormal heart function attributable to pericardial thickening.

• Reviewers noted that since the study focused specifically on the heart, it could not rule out other potential health outcomes associated with living in Vieques, including other potential effects of noise and vibration. Also, a study of commercial fishermen, a single occupational group, may not be representative of the entire population.

When: The Summary Report for the Vieques Heart Study Expert Panel Review is publicly available on Oct. 23, 2001.

For more information: For a copy of the report, call toll free, 1-888-42-ATSDR (1-888-422-8737). Callers should refer to the "Vieques Heart Study." Or, see the ATSDR web site: http://www.atsdr.cdc.gov.