Ventricular fibrillation waveform characteristics are different in ischemic heart failure compared with structurally normal hearts.

@article{citeulike:3024214, abstract = {BACKGROUND: For prolonged VF, perfusion of the myocardium by pre-shock chest compressions can improve myocardial readiness for successful defibrillation. Characteristics of the VF waveform correlate with the duration of VF when there is no structural heart disease. A "smart" automated external defibrillator (AED) could therefore analyze the VF waveform, determine if VF has been prolonged, and then direct rescuers to either deliver a shock first or chest compressions first. We hypothesized that ischemic heart failure might alter the waveform content of ventricular fibrillation compared with normal hearts, complicating the determination of VF duration. METHODS: Myocardial infarction was induced by ligating the proximal left coronary artery. Six weeks later, VF was then induced in 10 rats with myocardial infarction and heart failure (MI-CHF) and 9 control rats. Waveforms were analyzed for total signal amplitude, median frequency, dominant frequency and bandwidth (the frequency interval containing 50\% of the total amplitude about the median frequency). RESULTS: All of these VF waveform characteristics were altered substantially in MI-CHF rats compared to normal controls. In particular, MI-CHF rats had decreased signal amplitude early in VF (p=0.02), a broader bandwidth (p=0.001) and different frequency characteristics over time (p<0.001). CONCLUSIONS: VF waveforms vary over time in a typical manner among rats with and without ischemic heart failure. However, the time-course and waveform characteristics of ventricular fibrillation are altered in rats with myocardial infarctions and ischemic heart failure compared to normal controls. These findings have important implications regarding the use of waveform analyses to determine the duration of VF.}, address = {Sarver Heart Center, University of Arizona College of Medicine, 1501 N. Campbell Avenue, Tucson, AZ 85724-5037, USA. jindik@email.arizona.edu}, author = {Indik, J. H. and Donnerstein, R. L. and Kern, K. B. and Goldman, S. and Gaballa, M. A. and Berg, R. A. }, citeulike-article-id = {3024214}, doi = {10.1016/j.resuscitation.2005.10.017}, issn = {0300-9572}, journal = {Resuscitation}, keywords = {arrest, cardiovascular, ecg, vf, wavelet}, month = {June}, number = {3}, pages = {471--477}, posted-at = {2008-07-21 12:59:00}, priority = {2}, title = {Ventricular fibrillation waveform characteristics are different in ischemic heart failure compared with structurally normal hearts.}, url = {http://dx.doi.org/10.1016/j.resuscitation.2005.10.017}, volume = {69}, year = {2006} }

TY - JOUR ID - citeulike:3024214 L3 - citeulike-article-id:3024214 TI - Ventricular fibrillation waveform characteristics are different in ischemic heart failure compared with structurally normal hearts. JF - Resuscitation VL - 69 IS - 3 SP - 471 EP - 477 AD - Sarver Heart Center, University of Arizona College of Medicine, 1501 N. Campbell Avenue, Tucson, AZ 85724-5037, USA. jindik@email.arizona.edu SN - 0300-9572 N2 - BACKGROUND: For prolonged VF, perfusion of the myocardium by pre-shock chest compressions can improve myocardial readiness for successful defibrillation. Characteristics of the VF waveform correlate with the duration of VF when there is no structural heart disease. A "smart" automated external defibrillator (AED) could therefore analyze the VF waveform, determine if VF has been prolonged, and then direct rescuers to either deliver a shock first or chest compressions first. We hypothesized that ischemic heart failure might alter the waveform content of ventricular fibrillation compared with normal hearts, complicating the determination of VF duration. METHODS: Myocardial infarction was induced by ligating the proximal left coronary artery. Six weeks later, VF was then induced in 10 rats with myocardial infarction and heart failure (MI-CHF) and 9 control rats. Waveforms were analyzed for total signal amplitude, median frequency, dominant frequency and bandwidth (the frequency interval containing 50% of the total amplitude about the median frequency). RESULTS: All of these VF waveform characteristics were altered substantially in MI-CHF rats compared to normal controls. In particular, MI-CHF rats had decreased signal amplitude early in VF (p=0.02), a broader bandwidth (p=0.001) and different frequency characteristics over time (p<0.001). CONCLUSIONS: VF waveforms vary over time in a typical manner among rats with and without ischemic heart failure. However, the time-course and waveform characteristics of ventricular fibrillation are altered in rats with myocardial infarctions and ischemic heart failure compared to normal controls. These findings have important implications regarding the use of waveform analyses to determine the duration of VF. KW - arrest KW - cardiovascular KW - ecg KW - vf KW - wavelet AU - Indik, JH AU - Donnerstein, RL AU - Kern, KB AU - Goldman, S AU - Gaballa, MA AU - Berg, RA PY - 2006/06// UR - http://dx.doi.org/10.1016/j.resuscitation.2005.10.017 ER -