Hrev_master [page 69] [Emergency Care Journal 2017; 13:7144] Global T waves inversion and QT prolongation. An uncommon presentation of acute pulmonary embolism Simone Savastano,1 Martina Querio,2 Ernesto Anesi,3 Rita Camporotondo4 1Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia; 2School of Cardiovascular Disease, University of Pavia; 3Emergency Department, Fondazione IRCCS Policlinico San Matteo, Pavia; 4Intensive Coronary Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy Abstract This is the case of a man presenting to the emergency department for dyspnea. Despite a very common symptom he pre- sented an uncommon twelve leads electro- cardiogram (ECG). At a first glance it could have suggested an acute coronary syn- drome, a Takotsubo cardiomyopathy or a hypertrophic cardiomyopathy. However the further investigations showed an acute pul- monary embolism (APE) whose pre-test probability was low with a Wells score of 0 and a Geneva simplified score of 1. Negative T waves have been described in APE, however, such a morphology associat- ed with QT prolongation is a very rare pres- entation. This case confirms how the diag- nosis of APE could be often insidious repre- senting a challenge for the emergency physician. Case Report This is the case of a 82-year-old male who presented to the emergency department of our Hospital after four days of exertional dyspnea. He used to lead an active life until the onset of symptoms. Dyspnea appeared suddenly with a constant progression to ever-smaller efforts. His past medical histo- ry was negative, with the exception of arte- rial hypertension. No past cardiac diseases or other comorbidities were known. On physical examination lung and heart sounds were clear with a systolic murmur in cen- trum cordis; abdomen examitation’s find- ings were negative, no peripheral edema or jugular vein distension were detected. Laboratory tests showed a normal complete blood count, serum creatinine was 1.82 mg/dL, cardiac troponine I was 0.06 ng/mL (URL 0,04 ng/mL). Figure 1 shows the ECG at admission. The ECG shows a regular sinus rhythm at 66 beats per minute, a normal atrio-ven- tricular conduction, a normal QRS duration and global large and symmetrical T waves inversion (max 9 mm in V3) with a QT pro- longation (QT/QTc = 600/632 ms). Despite a very low pretest probability with a Wells score of 0 and a Geneva sim- plified score of 1 the echocardiographycal examination showed a right ventricle dilata- tion with reduced systolic function and sys- tolic compression of the left ventricle which showed a preserved systolic function. A compression ultrasound examination of the lower limbs was provided outlining a deep venous thrombosis involving the left femoral and popliteal veins. The arterial blood gas test showed hypoxia (PaO2 = 52.9 mmHg) and hypocapnia (PaCO2 = 24 mmHg), potassium level was normal (4.6 mmol/L); the D-dimer DD10 was 12105 µg/L (URL 500 µg/L). Finally a chest CT scan confirmed the diagnosis of massive pulmonary embolism (Figure 2). Discussion Negative T waves have been described in many clinical conditions such as acute coronary syndromes, Takotsubo cardiomy- opathy, hypertrophic cardiomyopathy, acute cerebrovascular events, ionic disorders and acute pulmonary embolism (APE). The first description of negative T waves in APE was by Lowe et al.1 in 1938. A case series by Ferrari et al.2 published in 1997 analyzed the different ECG manifestations of APE and it was pointed out that T wave inversion in the anterior leads may be present in about 60% of the patients. Usually this presenta- tion suggests a worse prognosis and can appear some days after the onset of symp- toms. A more recent paper3 sought for dif- ferences among T waves morphology occurring in acute coronary syndromes, in Takotsubo cardiomyopathy and in APE. In APE T waves usually remain positive in I, aVL (as in our case) and only in few cases T waves may be negative in V5, V6 and II. In the same paper the maximal T wav nega- tivity was also compared and it was shown that in APE T waves were less negative than in the other two conditions with a maximal negativity of 3.4 mm. In our case T wave inversion was in some ways atypical for APE as T waves were negative also in II e V5 and mostly in V6 with a maximal negativity of about 9 mm; there was no sinus tachycardia also frequent in APE, and the QT interval was prolonged. The underlying mechanism of T waves inversion in APE is not completely known and some theories have been proposed. The first and the most accredited is the coronary insufficiency due to the decreased perfusion of the right ventricle caused by the increase of ventricular pressures and by the increase of afterload. Another possible explanation may be the effect of an increased release of catecholamine due to hypoxia and hypoten- sion. The most recent theory lies on the potential effect of histamine release. The suffering lung tissue may release histamine which can induce myocardial ischemia and coronary vasospasm. From our perspective it appears quite difficult to find out a single mechanism which can justify the ECG pat- tern. The most likely hypothesis is a combi- nation of the various mechanisms described above. In particular the prolongation of the QT interval suggest an underlying ischemia. Of course a previous ECG could have been interesting but it was not available. Conclusions In conclusion the current ECG with its atypical elements provides the occasion to meditate on the diagnosis of APE which is Emergency Care Journal 2017; volume 13:7144 Correspondence: Simone Savastano, Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Piazzale Golgi, 27100 Pavia, Italy. Tel.: +39.0382.501590 - Fax: +39.0382.503161. E-mail: s.savastano@smatteo.pv.it Key words: ECG, pulmonary embolism, T waves. Contributions: SS, cardiologist, evaluated the patients in the emergency department; MQ, fellow in cardiology, was present during the evaluation in the emergency department and recovered the material for the drafting of the clinical case; EA, physician, took care of the patient in the emergency department; RC, car- diologist, took care of the patient in the inten- sive coronary unit. Conflict of interest: the authors declare no potential conflict of interest. Received for publication: 15 October 2017. Revision received: 12 January 2018. Accepted for publication: 20 February 2018. This work is licensed under a Creative Commons Attribution 4.0 License (by-nc 4.0). ©Copyright S. Savastano et al., 2017 Licensee PAGEPress, Italy Emergency Care Journal 2017; 13:7144 doi:10.4081/ecj.2017.7144 Non -co mmerc ial us e o nly very often difficult and insidious represent- ing a challenge for the emergency physi- cian. References 1. Lowe WS, Brugler GW, Winslow N. Electrocardiographic studies of clinical and experimental pulmonary emoboli- sation. Ann Intern Med 1938;11:2109- 23. 2. Ferrari E, Imbert A, Chevalier T, et al. The ECG in pulmonary embolism. Predictive value of negative T waves in precordial leads 80 case reports. Chest 1997;111:537-43. 3. Kosuge M, Ebina T, Hibi K, et al. Differences in negative T waves among acute coronary syndrome, acute pul- monary embolism, and Takotsubo car- diomyopathy. Eur Heart J Acute Cardiovasc Care 2012;1:349-57. Case Report Figure 1. ECG at admission showing regular sinus rhythm, normal atrio-ventricular con- duction and giant, global symmetrical T waves inversion and QT prolongation. Figure 2. Chest CT scan images outlining a subocclusive thrombosis of the right pul- monary artery and of the superior branch of the left pulmonary artery. [Emergency Care Journal 2017; 13:7144] [page 70] Non -co mmerc ial us e o nly