Effectiveness of respiratory-sinus-arrhythmia biofeedback on state-anxiety in patients undergoing coronary angiography.

AIM: This study is a report of a study conducted to evaluate the value of psychological assistance including respiratory-sinus-arrhythmia biofeedback training in its ability to reduce the level of anxiety in patients undergoing coronary angiography. BACKGROUND: Coronary angiography has been reported to cause anxiety and emotional stress. METHODS: Between March 2004 and January 2005, 212 patients undergoing routine elective coronary angiography for the evaluation of stable coronary artery disease were randomized into two groups. In the psychological support group (n = 106) a structured psychological conversation and respiratory-sinus-arrhythmia biofeedback training were offered prior to coronary angiography. In the control group (n = 106) standard care and information was provided without psychological support. State-anxiety was measured (scale 20-80) 1 day prior to and after coronary angiography, along with blood pressure and heart rate. FINDINGS: Prior to coronary angiography, state-anxiety was 54.8 +/- 11.5 (mean +/- SD) in the control group and 54.8 +/- 12.6 in the psychological support group. After coronary angiography, state-anxiety was 47.9 +/- 18.5 in the control group but 28.3 +/- 12.5 in the psychological support group (Wilcoxon rank sum test W = 7272, P < 0.001). Blood pressure was statistically significantly lower in the psychological support group prior to the intervention and the day after coronary angiography. CONCLUSION: Psychological support including respiratory-sinus-arrhythmia biofeedback is an effective and simple tool that could be used by nurses to reduce state-anxiety and emotional stress in patients undergoing coronary angiography.

Baseline vectorcardiography as a predictor of invasively determined acute hemodynamic response to cardiac resynchronization therapy.

AIMS: Identifying potential responders to cardiac resynchronization therapy (CRT) may be sometimes difficult and time consuming. Searching for a simple method, we chose vectorcardiography (VCG) for our study. The aim was to evaluate whether a VCG parameter can be used to predict invasively measured acute hemodynamic changes after CRT onset. METHODS AND RESULTS: Baseline VCG data were prospectively recorded just before initiation of CRT in a series of 126 consecutive patients (♂74 %, DCMP 60 %, ICMP 40 %, NYHA class III 100 %, QRS width 161 ± 27 ms, LV-EF 25 ± 6.5 %) prior to implantation at our specialized center. The time interval (TI) between the maximum vector and the end of the vector loop (initial description by Koglek W.) was correlated with acute hemodynamic change after CRT onset. Positive response to CRT was defined as an increase in dp/dt max >10 % or pulse pressure >5 %. According to these invasive hemodynamic parameters, 25 patients (20 %) were defined as non-responders. Using ROC analysis, the threshold value of the TI for responders was found to be 64 ms. TI is a predictor of acute hemodynamic response with a sensitivity of 96 %, a specificity of 76 %, a positive predictive value of 94 %, and a negative predictive value of 79 %. More non-responders are identified by TI than by using conventional QRS width in the 12-lead surface ECG. CONCLUSION: TI is a new method of evaluation based on baseline VCG analysis. It may be a useful diagnostic test for predicting acute hemodynamic response to CRT.