1. From the Institute of Scientific Instruments (J.H., P.J.), Academy of Sciences; St Anne’s University Hospital (T.K., M.S., M.N., R.P., J.T., J.S.); and the Faculty of Medicine (Z.N.), Masaryk University, Brno, Czech Republic; Mayo Clinic (T.K., W.K.S., V.K.S.), Rochester, Minn; Chelsea & Westminster Hospital (D.P.F.), London; Colchester General Hospital (L.C.D.), Colchester; and the National Heart & Lung Institute (A.J.S.C.), London, UK.