Table 2.

Pressure-volume analysis, IVPD, and vorticity data

	BL Before PL	PL	BL Before VL	VL	MIL
Heart rate, beats/min	110 ± 10	118 ± 9	117 ± 11	145 ± 15†	147 ± 35
Ejection fraction, ml	45 ± 15	33 ± 13*	44 ± 20	42 ± 7	54 ± 11‡
End-systolic volume, ml	18 ± 5	27 ± 8*	21 ± 9	32 ± 6†	25 ± 9‡
End-diastolic volume, ml	30 ± 2	37 ± 6*	34 ± 5	50 ± 5†	45 ± 12
End-systolic pressure, mmHg	100 ± 12	144 ± 11*	104 ± 10	90 ± 10†	96 ± 13
End-diastolic pressure, mmHg	11 ± 7	17 ± 6*	11 ± 7	20 ± 8†	14 ± 7‡
dP/dtmax, mmHg/s	1,849 ± 530	1,832 ± 268	2,160 ± 743	2,500 ± 813	4,175 ± 1,633‡
dP/dtmin, mmHg/s	−2,777 ± 488	−3,133 ± 502*	−3,035 ± 532	−2,534 ± 339	−3,145 ± 684
dV/dtmax, ml/s	143 ± 61	130 ± 24	158 ± 44	296 ± 45†	297 ± 71‡
dV/dtmin, ml/s	−110 ± 30	−97 ± 18	−122 ± 30	−177 ± 33	−253 ± 85‡
τ, ms	32 ± 9	43 ± 6*	32 ± 10	35 ± 8	25 ± 8‡
Total IVPD, mmHg	1.8 ± 0.6	1.1 ± 0.3*	2.2 ± 0.7	3.3 ± 0.6†	5.3 ± 2.1
Basal IVPD, mmHg	0.9 ± 0.3	0.9 ± 0.2	1.3 ± 0.5	1.6 ± 0.5	2.3 ± 1.1
Mid IVPD, mmHg	0.8 ± 0.5	0.2 ± 0.2*	0.9 ± 0.6	1.5 ± 0.6	2.4 ± 0.8‡
Apical IVPD, mmHg	0.002 ± 0.002	0.03 ± 0.08	0.03 ± 0.06	0.2 ± 0.1†	0.6 ± 0.6
E-Vor, 1/s	335 ± 95	242 ± 84*	338 ± 93	451 ± 71	589 ± 122‡

Values are means ± SE. The time constant (τ) was prolonged with pressure loading (PL), unchanged with volume loading (VL), and shortened with mirlinone (MIL) administration. Both the mid intraventricular pressure difference (IVPD) and peak early diastolic vorticity (E-Vor) showed same changes as τ under various loading conditions. BL, baseline.

^*P < 0.05 compared with BL;

^†P < 0.05 compared with BL before VL;

^‡P < 0.05 compared with VL.