The vasodilator stress ECG: Should depression cause anxiety?

Excerpt

For more than a century, the resting electrocardiogram (ECG) has endured as the cornerstone in the diagnosis of cardiac disease. The information provided from the modern day version of Einthoven’s string galvanometer1 remains at times more useful than other more sophisticated technology, as evidenced by its central role in the management of acute chest pain, with the decision to pursue a reperfusion strategy based almost exclusively on the presence of diagnostic ECG findings.2 The ECG also provides us with important information regarding the potential presence of coronary artery disease (CAD) and ischemia when interpreted during exercise and pharmacologic stress testing. While a very sensitive instrument, it suffers from a lack of specificity and consequent false positive results. As newer modalities to assess myocardial ischemia with imaging have evolved, diagnostic accuracy has increased, and many studies have demonstrated that imaging adds both incremental diagnostic and prognostic information to that predicted by the clinical data and ECG alone.3 Ischemic ECG changes during exercise stress testing have been demonstrated to provide additional prognostic information in the setting of perfusion abnormalities, but considered as “false-positive” when perfusion images are normal.4,5 Similar to exercise stress, stress ECG changes during pharmacologic stress can also be important. However, the diagnostic and prognostic significance of vasodilator-induced ischemic ECG changes in the setting of normal perfusion is less certain, as previous studies of this unique finding have demonstrated discordant results.6-9 …