PR deviation as a risk marker for cardiac events in patients with Takotsubo syndrome
Masato Shimizu1, Hiroyuki Fujii1, Makoto Suzuki1
1Department of Cardiology, Yokohama Minami Kyosai Hospital, Yokohama, Japan.
Background:
PR segment deviation (PRD: defined as PR elevation in aVR and PR depression in lead II/III) on electrocardiography is frequently observed in patients with acute pericarditis; however, there have been few studies that explore the occurrence of PRD in patients with Takotsubo syndrome (TTS). The clinical significance of PRD in TTS is not clearly elucidated.
Methods & Results:
A total of 52 consecutive patients with TTS in sinus rhythm (73.9 ± 13.8 years, nine males) were enrolled in the study. The major cardiac events were defined as sustained ventricular tachycardia or ventricular fibrillation, Killip class 4 heart failure, and cardiac death within 30 days. PRD in the hyperacute phase (within 48 h from the onset of TTS) was observed in 15 patients (29%), and all PRDs disappeared or diminished at 1 week later. The PRD (+) group had a higher value of C-reactive protein level (median: 1.80 mg/dL [0.31-3.26] vs 0.20 mg/dL [0.06-0.81], P = 0.013) and creatine kinase-muscle/brain isoenzyme (median: 60 IU/L [28-75] vs 17 IU/L [13-26], P < 0.001) and a lower level of left ventricular ejection fraction (42.7 ± 7.2% vs 48.8 ± 9.4%, P = 0.041) than the PRD (-) group. Multivariate analysis showed that PRD was a significant and independent predictor for major cardiac events (odds ratio = 21.0, 95% confidence interval = 1.18-273).
Conclusions:
TTS patients with PRD in the hyperacute phase showed a high incidence of major cardiac events. Therefore, PRD may help to identify TTS patients at high risk for cardiac event.
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