PMC6875455_01
(A) On 12-lead electrocardiography (ECG) at the patient's first visit to our hospital, the V2 lead showed a coved-type ST segment elevation, while the V3 lead showed a slight saddleback ST segment elevation. (B) ECG findings in the precordial leads recorded from one intercostal space (ICS) above the usual position in the same examination as A. An obvious coved-type ST segment elevation in the right precordial leads at one (upper third) ICS was recorded. (C and D) Signal-averaged ECG was recorded from ventricle (C) and atrium(D), respectively. Both late potentials were clearly positive during the patient's first visit to our hospital. c-fPd, filtered P wave duration; c-fQRSd, filtered QRS interval duration; LAS40, low-amplitude signal duration under 40 mV; RMS20 and RMS40, root mean square voltages of the last 20 and 40 ms of the QRS complex, respectively.
1349-7235-58-3099-g001.jpg
PMC6875455_01_1349-7235-58-3099-g001.jpg
g001
During a medical examination, a 30-year-old woman was diagnosed to have BrS on ECG in which the right precordial leads indicated an obvious coved-type ST segment elevation (Fig. 1A and B).
(A) Twelve-lead Holter electrocardiography showed sinus arrest (4.34 seconds) at 11: 00 AM. An abrupt long pause due to sinus arrest was immediately followed by an augmented ST segment elevation in the right precordial leads. (B) A chest radiograph after the placement of an implantable cardioverter defibrillator, with a cardiothoracic ratio of 40.8%.
1349-7235-58-3099-g002.jpg
PMC6875455_01_1349-7235-58-3099-g002.jpg
g002
Despite ECG findings indicative of BrS, she had no symptoms; therefore, she was carefully observed at the outpatient clinic of our hospital. During follow-up, Holter ECG was performed because she reported occasional fainting spells and dizziness, and showed sinus node dysfunction (maximal RR interval, 4.34 seconds) was observed with frequent episodes of sinus arrest associated with dizziness (Fig. 2A). However, the sinus node dysfunction did not improve sufficiently, and therefore an ICD was placed (Fig. 2B).
(A) Five electrocardiograms (ECGs, leads V1 and V2) recorded at different times from the third intercostal space (ICS) during serial periods of nonpregnancy and pregnancy. ECGs were recorded during the 38th week of the first pregnancy and during the 21st week of the second pregnancy. (B) Changes in the value of J-point amplitudes in lead V2 (third ICS) during the same periods as the ECG recordings in part A. The J-point amplitudes decreased during pregnancy, but not during the nonpregnancy periods.
1349-7235-58-3099-g003.jpg
PMC6875455_01_1349-7235-58-3099-g003.jpg
g003
Furthermore, the ST segment elevations in the right precordial leads were attenuated during the second and third trimesters of pregnancy, in comparison to the periods when she was not pregnant (Fig. 3).