Table I.

Comparison of measured ultrasonic myocardial velocities of the current study with previous measurements from other laboratories (mean ± one standard deviation).

	Velocity Parallel to Myofibers (m/s)	Velocity Perpendicular to Myofibers (m/s)	Magnitude of Anisotropy Of Velocity (m/s)	Ratio of Parallel to Perpendicular
Results of Current Study:
Freshly Excised Bovine Myocardium	1565 ± 5	1557 ± 4	8 ± 3	0.51%
Freshly Excised Ovine Myocardium	1565 ± 4	1556 ± 4	9 ± 2	0.58%
Formalin-Fixed Ovine Myocardium	1581 ± 4	1568 ± 3	12 ± 3	0.83%
Results of Previous Studies:
Freshly Excised Bovine 23 ± 1°C, 20–40 MHz (Akashi et al. 1995)	1565 – 1570a		-	-
Freshly Excised Calf 22 ± 1°C, 5 MHz (Shung & Reid 1977 & 1978)	-	1546 ± 4	-	-
Freshly Excised Bovine 23 ± 0.5°C, 5 MHz (Fei, Shung, & Wilson 1987)	-	1558 ± 4	-	-
Freshly Excised Canine 20 ± 2°C, 5 MHz (Mol & Breddels 1982)	1558 ± 6	1550 ± 6	7 ± 3	0.52%
Formalin-Fixed Calf 22 ± 1°C, 5 MHz (Shung & Reid 1977)	-	1559 ± 7	-	-
Formalin-Fixed Human 18.1 ± 1.2°C, 5 MHz (Verdonk, Wickline, Miller 1992)	1550 ± 5	1530 ± 3	20 ± 6 (reportedb) 12 (re-analyzed using RF correlationb)	-

^aangle of insonification relative to predominant direction of myofibers not specified

^bsee Appendix