[1] Univ Maryland, Sch Med, Baltimore, MD 21201 USA
[2] Univ Washington, Med Ctr, Seattle, WA 98195 USA
[3] Lenox Hill Hosp, New York, NY 10021 USA
[4] OHSU, Portland, OR USA
[5] Univ Calif Los Angeles, Los Angeles, CA USA
[6] Johns Hopkins Bayview Med Ctr, Baltimore, MD USA
[7] Methodist Hosp, Houston, TX 77030 USA
[8] Univ Texas Med Sch Houston, Houston, TX USA
[9] Intermt Med Ctr, Murray, UT USA
[10] Univ N Carolina, Sch Med, Sanger Heart & Vasc Inst, Charlotte, NC 28223 USA
[11] Geisinger Med Ctr, Danville, PA 17822 USA
[12] Univ So Calif, Keck Sch Med, Los Angeles, CA 90033 USA
[13] Univ Rochester, Rochester, NY USA
[14] Baptist Hosp W Inc, Knoxville, TN USA
[15] So Illinois Univ, Springfield, IL USA
[16] Henry Ford Hosp, Detroit, MI 48202 USA
[17] Mayo Clin, Jacksonville, FL 32224 USA
[18] Univ Alabama Birmingham, Birmingham, AL USA