Effect of QRS morphology on clinical event reduction with cardiac resynchronization therapy: meta-analysis of randomized controlled trials.
ABSTRACT Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in systolic heart failure patients with a wide QRS. Previous retrospective studies suggest only patients with QRS prolongation due to a left bundle-branch block (LBBB) benefit from CRT. Our objective was to examine this by performing a meta-analysis of all randomized controlled trials of CRT.
Systematic searches of MEDLINE and the Food and Drug Administration official website were conducted for randomized controlled CRT trials. Trials reporting adverse clinical events (eg, all-cause mortality, heart failure hospitalizations) according to QRS morphology were included in the meta-analysis.
Four randomized trials totaling 5,356 patients met the inclusion criteria. In patients with LBBB at baseline, there was a highly significant reduction in composite adverse clinical events with CRT (RR = 0.64 [95% CI (0.52-0.77)], P = .00001). However no such benefit was observed for patients with non-LBBB conduction abnormalities (RR = 0.97 [95% CI (0.82-1.15)], P = .75). When examined separately, there was no benefit in patients with right-bundle branch block (RR = 0.91 [95% CI (0.69-1.20)], P = .49) or non-specific intraventricular conduction delay (RR = 1.19 [95% CI (0.87-1.63)], P = .28). There was no heterogeneity among the clinical trials with regards to the lack of benefit in non-LBBB patients (I(2) = 0%). When directly compared, the difference in effect of CRT between LBBB versus non-LBBB patients was highly statistically significant (P = .0001 by heterogeneity analysis).
While CRT was very effective in reducing clinical events in patients with LBBB, it did not reduce such events in patients with wide QRS due to other conduction abnormalities.
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ABSTRACT: This study used a computer-based emotional word-recognition task to assess the emotional processing styles of repressive–defensive youth. A hypothesis was tested proposing that adolescent repressive–defensive coping style is associated with rapid engagement and disengagement of emotional stimuli (negative and positive). Data were collected on a male adolescent sample enrolled in a juvenile diversion program allowing for the comparison of anxious, low-anxious, and repressive–defensive youth. Consistent with prediction, repressive–defensive participants exhibited facilitated responding to emotional relative to neutral word stimuli across valence category (i.e., positive and negative). In contrast, anxious participants exhibited a unique pattern of facilitated responding to positive word stimuli. The current findings represent a first attempt at investigating the processing impairments of repressive–defensive coping style in a nonadult sample. Results are interpreted in light of broader adult and child research findings on emotional processing and affective disturbance.Journal of Psychopathology and Behavioral Assessment 02/2005; 27(1):1-9. · 1.55 Impact Factor
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ABSTRACT: Recognition of facial expressions of emotions is very important for communication and social cognition. Neuroimaging studies showed that numerous brain regions participate in this complex function. To study spatiotemporal aspects of the neural representation of facial emotion recognition we recorded neuromagnetic activity in 12 healthy individuals by means of a whole head magnetoencephalography system. Source reconstructions revealed that several cortical and subcortical brain regions produced strong neural activity in response to emotional faces at latencies between 100 and 360 ms that were much stronger than those to neutral as well as to blurred faces. Orbitofrontal cortex and amygdala showed affect-related activity at short latencies already within 180 ms after stimulus onset. Some of the emotion-responsive regions were repeatedly activated during the stimulus presentation period pointing to the assumption that these reactivations represent indicators of a distributed interacting circuitry.Neuroscience Letters 06/2003; 342(1-2):101-4. · 2.03 Impact Factor
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ABSTRACT: Threat-related attentional disruptions in anxiety may relate to changes in cognitive control during task processing. The present study examined this question using the N2 event-related brain potential. It was predicted that threat stimuli will selectively influence the N2 for those showing elevated trait anxiety and that reduced N2 may reflect a compensatory process predicting better attention performance. EEG was recorded while 36 participants completed a cued flanker task with threat or nonthreat distracters. N2 amplitudes were greater to incongruent versus congruent flankers. Following threat, high trait anxious participants showed reduced modulation of the N2 by flanker type and greater N2 amplitudes to congruent flankers. Reduced N2 was associated with better attention performance. This study was among the first documenting the emotional modulation of the N2 related to the threat bias and its links with attention interference in anxiety.Psychophysiology 12/2008; 46(1):122-31. · 3.26 Impact Factor