Background-Observational studies have suggested that psychological stress increases the incidence of sudden cardiac death. Whether emotional or physical stressors can trigger spontaneous ventricular arrhythmias in patients at risk has not been systematically evaluated. Methods and Results-Patients with implantable cardioverter-defibrillators (ICDs) were given diaries to record levels of defined mood states and physical activity, using a 5-point intensity scale, during 2 periods preceding spontaneously occurring ICD shocks (0 to 15 minutes and 15 minutes to 2 hours) and during control periods 1 week later. ICD-stored electrograms confirmed the rhythm at the time of shock. A total of 107 confirmed ventricular arrhythmias requiring shock were reported by 42 patients (33 men; mean age, 65 years; 78% had coronary artery disease) between August 1996 and September 1999. In the 15 minutes preceding shock, an anger level Ն3 preceded 15% of events compared with 3% of control periods (PϽ0.04; odds ratio, 1.83; 95% confidence intervals, 1.04 to 3.16) Other mood states (anxiety, worry, sadness, happiness, challenge, feeling in control, or interest) did not differ. Patients were more physically active preceding shock than in control periods. Anger and physical activity were independently associated with the preshock period. Conclusions-Anger and physical activity can trigger ventricular arrhythmias in patients with ICDs. Future investigations of therapies aimed at blocking a response to these stressors may decrease ventricular arrhythmias and shocks in these

The frequency of cardiovascular abnormalities was evaluated in 71 consecutive patients with acute injury to the spinal cord. Persistent bradycardia was universal in all 31 patients with severe cervical cord injury and less common in milder cervical injury (6 of 17) or thoracolumbar injury (3 of 23) (p less than 0.00001). Marked sinus slowing (71 versus 12 versus 4%, respectively, p less than 0.00001), hypotension (68 versus 0 versus 0%, p less than 0.00001), supraventricular arrhythmias (19 versus 6 versus 0%, p = 0.05) and primary cardiac arrest (16 versus 0 versus 0%, p less than 0.05) were significantly more frequent in the severe cervical injury group. The frequency of bradyarrhythmias peaked on day 4 after injury and gradually declined thereafter. All observed abnormalities resolved spontaneously within 2 to 6 weeks. The primary mechanism underlying these observations appears to involve the acute autonomic imbalance created by the disruption of sympathetic pathways located in the cervical cord. Acute severe injury to the cervical spinal cord is regularly accompanied by arrhythmias and hemodynamic abnormalities not found with thoracolumbar cord trauma. These abnormalities are limited to the first 14 days after injury, a period in which life-threatening disturbances must be anticipated.

Mental stress alters VT cycle length and termination without evidence of ischemia. This suggests that mental stress may lead to sudden death through the facilitation of lethal ventricular arrhythmias.

Background-Stratifiers of sudden and total mortality risk are needed to optimally target preventive therapies in patients with coronary artery disease and impaired ventricular function. We assessed the prognostic significance of ECG markers of conduction abnormalities and left ventricular hypertrophy in the Multicenter Unsustained Tachycardia Trial (MUSTT). Methods and Results-We analyzed the ECGs of 1638 patients from MUSTT who did not receive antiarrhythmic therapy (antiarrhythmic medication or implantable cardioverter-defibrillator). After adjustment for other significant factors, left bundle-branch block and intraventricular conduction delay were associated with a 50% increase in the risk of both arrhythmic and total mortality. Right bundle-branch block was not associated with arrhythmic or total mortality. Left ventricular hypertrophy was the only ECG predictor of arrhythmic (hazard ratio, 1.35; 95% CI, 1.08 to 1.69) but not total mortality. Conclusions-In patients with coronary artery disease, depressed left ventricular function, and nonsustained ventricular tachycardia, QRS prolongation resulting from left bundle-branch block or intraventricular conduction delay but not right bundle-branch block provided prognostic information about the risk of arrhythmic and total mortality independently of electrophysiological evaluation and ejection fraction. Left ventricular hypertrophy was associated with increased arrhythmic but not total mortality.

As the use of ICDs increases, more young patients will be eligible to receive these devices. Such patients may have different concerns than older patients who more commonly receive ICDs. We investigated quality-of-life issues in patients followed by the Yale electrophysiology service who were < or = 40 years old (mean = 28) at the time of ICD implant. Mean time since ICD placement was 3.3 years. Each patient received a modified SF-36 health questionnaire; 16 (88%) of 18 responded. Nine were women; ten were married. The highest education level attained was high school for 6 (37%), and college or beyond for 10 (63%). Ten patients were employed; eight held the same job before and after ICD placement. Four women conceived after ICD implantation; one experienced ICD discharge during pregnancy. All delivered healthy infants. All patients felt their health was good to excellent, with 6 (38%) reporting an improvement in health since ICD placement. All felt capable of performing the activities of daily living, while 68% engaged freely in moderate physical activities. All patients felt they were average to very attractive. However, 63% worried about how their clothes fit with the ICD. Three quarters of the patients felt the ICD interfered with social interactions, while 50% were concerned about sexual encounters. Thus, even though these young patients have body image concerns and may limit their activities to some degree, they are productive, active members of society who have benefitted from ICD placement.

Psychological stress increased TWA, Tamp, and Tarea. Autonomically mediated repolarization changes may be a pathophysiologic link between emotion and arrhythmia in susceptible patients.

Stable psychological factors are associated with risk for ICD-shock triggered by concordant strong emotion.

In patients with coronary artery disease, sustained VT displays circadian variation with peak frequency in the morning, similar to that for sudden death. Individual patients who display specific patterns of circadian variation over time can be identified using defibrillator logs. Investigation of circadian variation of other phenomena to elucidate mechanisms of VT should focus on these patients.