Transient attenuation of the amplitude of the QRS complexes in the diagnosis of Takotsubo syndrome

Abstract

Background and objectives: Currently, there are no specific diagnostic electrocardiogram (ECG) signs for Takotsubo syndrome (TTS) to differentiate it from acute coronary syndromes (ACS). Myocardial oedema has been detected by cardiac magnetic resonance imaging in patients with TTS. Recently it has been postulated that myocardial oedema may be the cause of low QRS voltage (LQRSV) in the admission ECG and attenuation of the amplitude of the QRS complexes (AAQRS) in serial ECGs, noted in a few published cases of patients with TTS. The objective of this study was to evaluate whether the admission ECG of patients with documented TTS reveals LQRSV and whether AAQRS is found when serial ECGs are compared in such patients.

Methods: This study evaluated the prevalence of LQRSV in the admission ECG and AAQRS in serial ECGs in patients with TTS. ECGs of 368 patients with TTS from published reports in the international literature were evaluated for LQRSV (≤5 mm in limb leads and/or ≤10 mm in precordial leads) and AAQRS in serial ECGs.

Results: LQRSV was seen in 91.5% of 200 patients with TTS and one ECG, with a distribution of 49.0, 42.8, 51.0, 52.0, and 46.9%, in lead aVR, and inferior, anterior, lateral, and high lateral ECG lead groups, respectively. AAQRS was seen in 93.5% of 168 patients with TTS and two or more ECGs, with a distribution of 78.3, 74.5, 60.1, 70.7, and 74.5% in lead aVR, and inferior, anterior, lateral, and high lateral ECG lead groups, respectively.

Conclusions: LQRSV and AAQRS are highly prevalent ECG signs in patients with TTS, and should be useful in aiding in its diagnosis and differentiation from ACS, on first contact with the patient on admission to the hospital, and the ensuing 24 hours, in conjunction with echocardiography and coronary arteriography.

Keywords: Attenuation of the QRS complexes; Takotsubo syndrome; cardiac magnetic resonance imaging; diagnosis; electrocardiogram; low ECG QRS voltage; myocardial oedema.

Figure 1.

Admission ECG of a 79-year-old woman who suffered an unprovoked attack of Takotsubo syndrome, showing low QRS voltage in all leads except V3 and V4. Reproduced from Teo B. A mimicry of an acute coronary syndrome. Emerg Med J 2007; 24: e25, with the permission of BMJ Publishing Group.

Figure 2.

Admission ECG of an 80-year-old woman who developed an attack of Takotsubo syndrome 30 minutes after attempting to resuscitate her husband who had suffered a cardiac arrest, showing low QRS voltage in all limb and V3–V6 ECG leads, along with ST-segment elevations and Q-waves. Reproduced from Van Der Bilt IAC, Van Dijk J, Van Den Brink RBA, et al. Examining the octopus pot: multimodality imaging of a typical Takotsubo cardiomyopathy. Echocardiography 2008; 25: 794–796, with the permission of John Wiley & Sons.

Figure 3.

ECGs on days 1 and 2 of hospitalization and at 30 days follow up (A–C, respectively) of a 59-year-old woman who suffered Takotsubo syndrome in the setting of an epileptic seizure. The reversible attenuation of the amplitude of the QRS complexes (day 2) in the ECG leads, is clearly shown in the limb leads and leads V1 and V2, in comparison with the QRS amplitude on days 1 and 30. Reproduced and adapted from Sakuragi S, Tokunaga N, Okawa K, et al. A case of takotsubo cardiomyopathy associated with epileptic seizure: reversible left ventricular wall motion abnormality and ST-segment elevation. Heart Vessels 2007; 22: 59–63, with the permission of Springer.

Figure 4.

ECGs of an 84-year-old woman on presentation with her fourth attack of Takotsubo syndrome after being emotionally distressed for 2 days, on the anniversary of her husband’s death. Note the attenuation of the amplitude of the QRS complexes in the admission ECG (A) in comparison with an ECG recorded 1 year earlier (B) in all ECG leads except V1 and V2, although partially this is due to magnification in B which is greater than it is in A, as appreciated from the calibration signal and the ECG grid thick-to-thick lines distance. Reproduced from Vittala SS, Najib MQ, Click RL, et al. Left anterior descending coronary artery stenosis in a patient with Takotsubo cardiomyopathy. Tex Heart Inst J 2012; 39: 125–128, with the permission of the Texas Heart Institute.