The QS2/QT ratio as an index of appropriate left ventricular response to autonomic and inotropic stimuli. - Cokkinos, D.V.; Rivas, A; Perrakis, C; Diakoumakos, N; De, EG Puey; Burdine, JA; Leachman, RD; Hall, RJ (Acta cardiologica, 1986)