End-Systolic Elastance and Ventricular-Arterial Coupling Reserve Predict Cardiac Events in Patients with Negative Stress Echocardiography

Table 2

Stress echocardiography induced variation in cardiovascular hemodynamics.

𝑛(%) or mean ± SD	Exercise stress echo	Dipyridamole stress echo	Dobutamine stress echo
Patients	172 (19%)	482 (54%)	237 (27%)
Age, years	59±13^§	63 ± 12	66 ± 10
Males	133 (77%)	287 (60%)*	173 (73%)
Body mass index (kg/m^2)	1.87 ± 0.18^‡	1.85 ± 0.2*	1.81 ± 0.18
Left ventricular ejection fraction (%)
Rest	53 ± 14^‡	50 ± 17*	39 ± 15
Peak stress	60 ± 17^‡	57 ± 18*	51 ± 17
Reserve	7 ± 9^‡	7 ± 8*	12 ± 9
Heart rate × systolic blood pressure
Rest	9,546 ± 2,461^‡	9,579 ± 2,393*	8,253 ± 2,058
Peak stress	22,652 ± 6,430^§	11,035 ± 2,749*	18,027 ± 6,118
Reserve	13,105 ± 5,875^§	1,455 ± 2,131*	9,773 ± 6,219
𝐸LVI/𝐸aI
Rest	1.33 ± 0.70^‡	1.23 ± 0.70*	0.79 ± 0.56
Peak stress	2 ± 1.34^‡	1.76 ± 1.15*	1.36 ± 0.98
Reserve	0.67 ± 0.96	0.53 ± 0.78	0.57 ± 0.62
𝐸LVI, mmHg·mL^−1·m^−2
Rest	5.86 ± 4.21^‡	5.37 ± 3.21*	3.17 ± 2.42
Peak stress	12 ± 9.1^§	6.28 ± 4.17	6.46 ± 6.12
Reserve	6.18 ± 6.1^§	0.91 ± 2.46*	3.29 ± 4.17
𝐸aI, mmHg·mL^−1·m^−2
Rest	4.28 ± 1.39^¶	4.97 ± 2.82*	4.13 ± 1.5
Peak stress	6.1 ± 2.7^§	4.19 ± 2.56	4.35 ± 1.76
Reserve	1.65±1.95^§	−0.78 ± 1.42*	0.22 ± 1.62
SWI, mmHg·mL^−1·m^−2
Rest	3,465 ± 1,156^‡	3,594 ± 1,457*	3,082 ± 1,235
Peak stress	4,963 ± 1,705^§	3,624 ± 1,440*	4,274 ± 1,665
Reserve	1,498 ± 1,607^¶	30 ± 1,035*	1,192 ± 1,330
PVA, mmHg·mL^−1·m^−2
Rest	5,248 ± 1,947^‡	5,971 ± 2,159	5,844 ± 2,234
Peak stress	6,852 ± 2,209^‡	5,202 ± 2,018*	6,728 ± 2,598
Reserve	1,604 ± 1,790^§	−395 ± 1,226*	884 ± 1,769
Stroke volume index (mL/m^2)
Rest	29.6 ± 8.6	29.3 ± 10.6	28.6 ± 9.5
Peak stress	30.2 ± 8.7^‡	32.3 ± 11.6	32.9 ± 10.2
Reserve	0.6±9.6^§	3.1 ± 7.5	4.4 ± 9.1
End-systolic pressure (mmHg)
Rest	117±19^§	122 ± 20*	107 ± 18
Peak stress	165±30^§	112 ± 19*	130 ± 28
Reserve	47±25^§	−10 ± 15*	23 ± 25
Heart rate (bpm)
Rest	73 ± 14	71 ± 14	70 ± 14
Peak stress	122±21^¶	89 ± 16*	123 ± 24
Reserve	49±19^¶	18 ± 13*	53 ± 28
Cardiac index (L·min·m^−2)
Rest	2.152 ± 704	2.044 ± 789	1.985 ± 746
Peak stress	3.693±1.246^§	2.847 ± 1.106*	4.008 ± 1.338
Reserve	1.540±1.153^§	803 ± 795*	2.023 ± 1.101
SVR (dyn·s^−1·cm^−5)
Rest	1,972 ± 696^¶	2,287 ± 1,113	2,187 ± 820
Peak stress	1,576 ± 880^‡	1,524 ± 911*	1,213 ± 481
Reserve	−442±619^§	−763 ± 668*	−974 ± 652

§Significant differences between exercise and both dipyridamole and dobutamine patients; ^‡significant differences between exercise and dobutamine pts; *significant differences between dipyridamole and dobutamine patients; ¶significant differences between exercise and dipyridamole patients.
𝐸_LVI/𝐸_aI: ventricular-arterial coupling ratio; 𝐸_aI: effective arterial elastance; 𝐸_LVI: left ventricular end-systolic elastance; PVA: pressure-volume area; SVR: systemic vascular resistance; and SWI: stroke work index.