The characteristics of the spectra of superior venae cavae in patients with right heart failure

Table 2 Peak velocities and VTI of D wave and their respiratory variation ratios ( ± s).

	Patients		Health subjects
	Peak velocity (cm/s)	VTI(mm)	Peak velocity (cm/s)	VTI(mm)
Inspiration	39.67 ± 26.52	0.0684 ± 0.0509	38.00 ± 9.15	0.0747 ± 0.0371
Expiration	34.43 ± 19.21	0.0580 ± 0.0354	24.73 ± 9.12	0.0454 ± 0.0243
Inspiratory variation ratio (%)	27.03 ± 16.34	33.72 ± 30.33	65.34 ± 44.38	86.18 ± 66.74
Expiratory variation ratio (%)	20.39 ± 13.40	29.98 ± 24.82	35.00 ± 17.96	45.16 ± 35.49

There were no differences in the peak velocities of D wave in inspiratory phase between the patient group and the control group (P > 0.05), but the peak velocities of D wave in expiratory phase were larger in the patient group than in the control group (P < 0.05), and the respiratory variation ratios of peak velocities of D wave were larger in the control group than in the patient group (P < 0.05); there were no differences in the VTI of D wave in respiratory cycle and its expiratory variation ratios between the patient group and the control group (P > 0.05), but the inspiratory variation ratios of VTI of D wave were larger in the control group than in the patient group (P < 0.05).

ISSN: 1476-7120