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Stress Echocardiography—State of the Art
Table 1: Selected Studies Enrolling More than 100 Patients with Coronary Angiographic Data to
Evaluate the Accuracy of Stress Echocardiography
Study Type of SE Coronary Angiography Total Number Sensitivity Specificity Accuracy
Cut-off (%) of Patients (%) (%) (%)
Armstrong et al., 1987
105
Treadmill 50 123 88 86 88
Crouse et al., 1991
106
Treadmill ≥50 228 97 64 89
Laucevicius et al., 1991
107
Transesophageal atrial pacing ≥70 121 93 91 93
Marwick et al., 1992
12
Treadmill 50 150 84 86 85
Hecht et al., 1993
108
Supine bicycle exercise 50 180 93 86 92
Ryan et al., 1993
109
Upright bicycle exercise 50 309 91 78 88
Roger et al., 1994
110
* Treadmill ≥50 150 73 70 NA
Beleslin et al., 1994
111
Treadmill 88 82 87
Dobutamine ≥50 136 82 77 82
Dipyridamole 74 94 77
Roger et al., 1995
10
Treadmill >50 127 88 72 88
Marwick et al., 1995
112
Treadmill >50 161 80 81 81
Marwick et al., 1995
113
Treadmill >50 147 71 91 82
Luotolahti et al., 1996
114
Treadmill >50 118 94 70 92
Roger et al., 1997
115
†
Treadmill ≥50 340 78 44 69
Marcovitz et al., 1992
116
Dobutamine >50 141 96 66 89
Marangelli et al., 1994
117
Treadmill 89 91 88
Transesophageal atrial pacing >50 104 83 76 73
Dipyridamole 43 92 63
Dagianti et al., 1995
118
Treadmill 76 94 87
Dobutamine >70 100 72 97 87
Dipyridamole 52 97 78
Nedeljkovic et al., 2006
119
Dobutamine 96 92 94
Dipyridamole ≥50 166 93 92 92
Treadmill 90 87 90
†
SE = stress echocardiography; NA = not available. *Reported for multivessel disease. Reported in men.
To date, clinical evaluation of SE imaging is mainly performed using accuracy of SE generally parallels the severity of CAD; multivessel
visual (qualitative) assessment based on comparison of rest and stress disease detection has higher accuracy than single-vessel.
images for global and regional dysfunction. The diagnostic criteria of
stress echocardiographic testing are centered on describing four The accuracy of SE has been compared with that of other non-
response patterns, including ‘normal,’ ‘inducible ischemia,’ ‘fixed scar invasive diagnostic imaging techniques such as nuclear perfusion
(necrosis),’ and ‘stunned’ or ‘biphasic response,’ as may be seen in imaging. Compared with nuclear perfusion, all types of SE—including
dobutamine SE viability studies. Furthermore, the site, extent, and transesophageal pacing—had marginally superior specificity for
severity of abnormal myocardial function, and ischemic threshold, can detection of CAD, while nuclear perfusion had marginally better
be identified.
3
The subjective interpretation of SE is highly dependent sensitivity.
13–24
The finding that stress nuclear perfusion is slightly more
on the skill and experience of the reviewing physician. In addition, it is sensitive can be explained by the ischemic cascade, whereby
affected considerably by image quality, which in the ‘pre-contrast era’ perfusion abnormalities precede wall-motion abnormalities.
was reported to be the case in up to 30% of SE exams.
12
Clear Interestingly, when direct comparison of contrast SE was made with
definition of endocardial border is crucial for optimal interpretation. nuclear imaging, contrast SE was more sensitive and slightly less
The use of ultrasound contrast agents for LVO and assessment of specific.
25
Nevertheless, SE has numerous advantages overall: it is
myocardial perfusion have added yet another dimension to SE.
5
easier to perform, has a relatively lower cost and greater spatial
resolution, and does not entail the use of ionizing radiation.
Diagnostic Accuracy and Prognostic Role
The diagnostic accuracy of SE for detecting obstructive CAD is affected SE has been shown to play an important role in the prediction of
by several factors, including type of stressor, adequacy of stress, mortality and composite cardiac events in patients with known or
severity and location of coronary stenosis, lesion morphology, number suspected CAD (see Table 2). A normal exercise SE is associated with
of involved coronary vessels, presence of anti-ischemic drugs, and state a mortality of <1%/year, while normal pharmacological stress has
of collateral circulation. The choice of one stress test modality over been associated with mortality <1.5% (patients undergoing
another will depend on the individual patient characteristics. Exercise, pharmacological stress have more comorbidities and, hence, a
transesophageal atrial pacing, and pharmacological (inotropic or greater cardiovascular disease burden).
26–30
The prognostic value of SE
vasodilator) SE have comparable diagnostic accuracy, as shown in has been evaluated in head-to-head comparative studies with nuclear
selected large studies (with >100 patients enrolled) (see Table 1). The perfusion imaging. These studies have shown a comparable event
US CARDIOLOGY 17