Dr. Joseph and his group1recently reported data in CHEST (November 2004) on the role of transthoracic echocardiography (TTE) in identifying cardiac etiologies of shock in the ICU. I congratulate the authors on their high rate of “adequate” TTE images (99%), but I find that it is a rate far exceeding the more common 80% “adequate” rate that is seen in many clinical practices, even with tissue harmonic imaging. Of note, the authors do not strictly define their criteria for image “adequacy,” which is the crux of the study. Further, there is no mention of the role of echogenic contrast agents, which have been shown to consistently improve image quality in difficult-to-image patients.2 Cardiac index, certainly a key value in patients who are in shock, was only able to be measured by TTE in 46% of the patients, whereas transesophageal echocardiography (TEE) studies can routinely derive this value in at least 90% of patients.3–4 Post-cardiac surgery patients were excluded from this study, as the authors note, but this is a very important group of patients who are at high risk for cardiogenic shock in whom TEE has been well-validated. Further, this study does not directly compare TTE to TEE. All of these points make me a bit hesitant to agree with the authors’ concluding statement, “TTE should be considered not only the initial, but also the principal echocardiographic test in the critical care environment.” As TTE technologies improve, this indeed may become the case, but the data presented here do not yet support such a change in clinical practice.