Pediatric Cardiology

Biography

Biography: Daniel Cortez

Abstract

Introduction. Tetralogy of Fallot patients carry a significant ventricular arrhythmia risk burden. If the risk burden is known then at the time of pulmonary valve replacement cryoablation lines can be placed to help treat these arrhthyhmias. Vectorcardiographic (VCG) principles may provide additional clinical information to the 12-lead electrocardiogram (ECG). We hypothesize that not only the QRS duration, but other QRS-specific VCG parameters may have predictive value for determining ventricular arrhythmia (VA) risk in on Tetralogy of Fallot (TOF) patients undergoing pulmonary valve replacements (PVR’s).
Results. Of the 73 patients analyzed, 11(15%) had newly diagnosed ventricular tachycardia. The RMSQRS and the QRSd showed significant differences between those with and those without newly diagnosed VA. RMSQRS for those with and without VA were 12.3±5.2mV vs. 16.5±7.3mV respectively (p<0.033), A cut-off value of 11.2dmV gave sensitivity and specificity of 73% and 77% respectively. The QRSd significantly differentiated those with VA versus those without, with values of 141.0±36.3ms vs. 165.6±25.0ms, respectively. At a cut-off value of 152ms the sensitivity and specificity were 73% and 53% respectively. For either RMSQRS of <11.2dmV or QRSd of 162ms, the sensitivity and specificity for VA was 91% and 92%, respectively with a relative risk of 11.2. No significant differences were found for the other parameters tested between these two groups.
Conclusion. In this retrospective analysis of TOF patients undergoing PVR’s, VCG evidence of quantifiable lower QRS voltage combined with QRSd give non-invasive significant and clinically useful ventricular arrhythmia risk stratification, similar to that reported for more invasive procedures.