Assessment of heart rate variability for prognostication of life expectancy in patients with advanced cancer

Abstract

Objectives: The goal of the study was to assess heart rate variability as a lifeexpectancy prognostication measure for patients with advanced cancer.Method: The first stage of the research was to implement a QRS detection algorithmwhich accurately discriminates normal heart beats (regular QRS complex) fromabnormal events (e.g. Premature Ventricular Contractions) from holter data filesrecorded using an orthogonal lead configuration (X, Y, and Z). Heart rate variabilitywas then assessed by calculating the standard deviation of the beat to beat intervals(SDNN = Standard deviation of N-N interval).Results: The algorithm was tested using data from the REFINE (Noninvasive RiskAssessment Early After a Myocardial Infarction) Study. 304 data files were evaluated.Normal beats were correctly classified with an accuracy of 99.9%, which correspondswell to other QRS detection algorithms. We are currently in the process of validatingour heart rate variability measures.Conclusion: We have developed a tool to assess heart rate variability. It ishypothesized that heart rate variability parameters can be used to discriminate patientswith short life expectancy (less than one week) from those with longer life expectancies.