Differences in Negative T Waves Between Acute Pulmonary Embolism and Acute Coronary Syndrome　― Reply ―

We thank Drs. Rubin and Montana for their interest in our study.¹ They propose a diagnostic approach using 3 ECG findings (i.e., the presence of both negative T waves (Neg T) in leads III and V1 and peak Neg T in leads V1–2, each finding alone, and the absence of both findings) for discriminating acute pulmonary embolism (APE) from acute coronary syndrome (ACS) caused by left anterior descending coronary artery disease.

We agree with their ECG approach, but make several comments about our study.¹ First, the ultimate goal of our study was to identify ECG criteria with higher sensitivity for the differential diagnosis of APE than that (88%) in our previous study.² The diagnosis of APE relies predominantly on the degree of clinical suspicion. We think that ECG criteria with high sensitivity for identifying APE are clinically important. They emphasize that the ECG criterion of both Neg T in leads III and V1 and peak Neg T in leads V1–2 strongly indicates APE, but the sensitivity was 76%. Second, each ECG finding alone is also important to raise the suspicion of APE. In our study patients with APE who had Neg T in leads III and V1, but not peak Neg T in leads V1–2, had very severe right ventricular dysfunction on echocardiography (data not shown). With increasing severity of right heart failure and dilation of the right ventricle towards the left, Neg T is thought to move towards the left; that is, from leads III to aVF to II in the limb leads and from leads V1 to V6 in the precordial leads. In these patients, the distribution of precordial Neg T is very similar to that of ACS, and therefore, more caution is required in differential diagnosis. In contrast, among the patients with APE who had peak Neg T in leads V1–2, but not Neg T in leads III and V1, most did not show right ventricular dysfunction on echocardiography (data not shown). In these patients, echocardiography did not contribute to the diagnosis of APE, and other imaging examinations, such as computed tomography or lung scanning, were required for a correct diagnosis. Finally, our ECG criteria (i.e., Neg T in leads III and V1 ‘ and/or’ peak Neg T in leads V1–2) are simple and identified APE with high predictive values (98% sensitivity, 92% specificity, 83% positive predictive value, and 99% negative predictive value).¹

We believe that our ECG criteria can be used for diagnosis in most physicians’ practices to help raise the suspicion of APE and indicate the need for further tests to establish a definitive diagnosis.

Disclosures

M.K. and K.K. are members of Circulation Journal’s Editorial Team.

• Masami Kosuge, MD
• Kazuo Kimura, MD
• The Division of Cardiology, Yokohama City University Medical Center, Yokohama, Japan

References

• 1.   Kosuge M, Ebina T, Hibi K, Tsukahara K, Iwahashi N, Umemura S, et al. Differences in negative T waves between acute pulmonary embolism and acute coronary syndrome. Circ J 2014; 78: 483–489.
• 2.   Kosuge M, Kimura K, Ishikawa T, Ebina T, Hibi K, Kusama I, et al. Electrocardiographic differentiation between acute pulmonary embolism and acute coronary syndromes on the basis of negative T waves. Am J Cardiol 2007; 99: 817–821.