Table 2.

Summary statistics for echocardiographic measurements at each treatment phase

	Summary statistics by study phase				Regression modeling results
	Before placebo	After placebo	Before sildenafil	After sildenafil	Coefficient	95% CI	p	n
Ventricular inflow
E velocity (cm/s)	83 (23)	81 (22)	80 (21)	87 (20)	5.0	(−0.69, 11)	0.08	27
A velocity (cm/s)	49 (15)	47 (14)	47 (16)	48 (14)	0.83	(−2.0, 3.7)	0.55	24
Tissue Doppler
S′ velocity (cm/s)	6.7 (1.9)	7.1 (1.9)	6.9 (1.5)	7.3 (1.8)	0.24	(−0.26, 0.73)	0.33	23
E′ velocity (cm/s)	11.1 (4.5)	11.6 (4.0)	10.8 (4.0)	11.8 (4.2)	0.43	(−0.69, 1.6)	0.43	23
A′ velocity (cm/s)	4.4 (1.4)	5.0 (2.1)	4.9 (2.4)	4.6 (1.9)	−0.090	(−0.66, 0.48)	0.75	21
Diastolic performance
E velocity/A velocity	1.8 (0.74)	1.9 (0.72)	1.9 (0.71)	2.0 (0.74)	0.038	(−0.12, 0.20)	0.63	24
E velocity/E′ velocity	8.4 (3.6)	7.8 (3.5)	8.8 (6.4)	8.3 (3.7)	0.26	(−0.95, 1.5)	0.66	23
Systolic performance
VTI (cm)	21.0 (5.5)	21.0 (5.9)	21.4 (5.0)	21.9 (6.0)	1.2	(−0.12, 2.5)	0.07	27
Heart rate (bpm)	69.7 (14)	71.3 (13)	70.7 (17)	73.0 (15)	1.9	(−2.6, 6.4)	0.40	26
VTI × HR (cm × bpm)	1442 (350)	1451 (310)	1466 (290)	1562 (420)	110	(7.5, 220)	0.04	26
Global ventricular performance
MPI	0.37 (0.11)	0.38 (0.13)	0.42 (0.14)	0.35 (0.10)	−0.051	(−0.095, -0.0077)	0.02	26

Data are presented as mean (SD), and regression modeling results for echocardiographic measurements are presented as coefficient, 95% CI, and p value. Each regression coefficient corresponds to the difference in the average post-phase outcome between sildenafil and placebo adjusted for pre-phase values, study period, and treatment sequence

n number of subjects with a complete measurement series