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Presentation Start/End Time:
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Tuesday, Apr
01, 2008, 10:00 AM -11:00 AM
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Author Block:
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Rachel
J. Lampert,
Vladimir Shusterman, Matthew Burg, William Batsford, Craig McPherson, Robert Soufer,
Yale University School of Medicine, New Haven, CT, University of Pittsburgh,
Pittsburgh, PA
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Background: Anger can precipitate ventricular arrhythmias, and induce T-wave alternans (TWA). However, whether anger-induced TWA
predicts future ventricular arrhythmias (VT/VF) is unknown.
Methods: Fifty-seven patients with ICDs (50
male, 63 ±12 years, 51 with CAD, 21 with history of prior clinical
arrhythmia) underwent ambulatory ECG monitoring during a laboratory mental
stress protocol including sequential resting-baseline and anger conditions,
three months after implant. Pacing was programmed VVI, 40 bpm,
resulting in sinus rhythm with native AV conduction in all. TWA was analyzed
continuously using time-domain methods. Patients were followed for ≥ 1
year (median 36 months) and ICD stored electrograms
and event details reviewed to determine incidence of VT/VF terminated by the
ICD.
Results: Patients with ICD-terminated VT/VF during follow-up (N=9) had
higher mean TWA induced by anger in the laboratory, 12.8± 1.0uV, compared to
those without subsequent VT/VF, 9.4±0.8uV (p<0.008). To evaluate the
predictive value of anger-induced TWA, the 15 subjects in the highest
quartile of anger-induced TWA were compared with the 41 in the bottom quartiles.
Patients in the top quartile were more likely to experience VT/VF by one year
than those in the lower quartile, 25% vs 5%,
(p<0.05), and during extended follow-up, 33% vs
9% (p<0.05.) After adjusting for heart rate during anger and length of
follow-up, the likelihood of VT/VF during follow-up for those in the top
quartile was 5.4 times that of the lower quartiles (95% CI 1.7-90,
p<0.03). In multivariable regression further controlling for ejection
fraction, history of prior clinical arrhythmia, and wide QRS, anger-induced
TWA was the only significant predictor of VT/VF, with likelihood in the top
quartile 7.8 times that of the lower(CI 1.2-81, p<0.05.) Kaplan-Meier
analysis confirmed that those in the top quartile were more likely to suffer
an ICD-terminated VT/VF (p<0.05)
Conclusion: Anger-induced TWA predicts future VT/VF in patients with ICDs, suggesting that emotion-induced repolarization
instability may be one mechanism linking stress and sudden death. Whether
there is a clinical role for anger-induced TWA testing requires further
study.
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