title: Development and validation of a risk calculator predicting exercise-induced ventricular arrhythmia in patients with cardiovascular disease.
abstract: BACKGROUND
  Mortality due to cardiovascular disease is often associated with ventricular arrhythmias. Nowadays, patients with cardiovascular disease are more encouraged to take part in physical training programs. Nevertheless, high-intensity exercise is associated to a higher risk for sudden death, even in apparently healthy people. During an exercise testing (ET), health care professionals provide patients, in a controlled scenario, an intense physiological stimulus that could precipitate cardiac arrhythmia in high risk individuals. There is still no clinical or statistical tool to predict this incidence. The aim of this study was to develop a statistical model to predict the incidence of exercise-induced potentially life-threatening ventricular arrhythmia (PLVA) during high intensity exercise.
  
  
  RESULTS
  6415 patients underwent a symptom-limited ET with a Balke ramp protocol. A multivariate logistic regression model where the primary outcome was PLVA was performed. Incidence of PLVA was 548 cases (8.5%). After a bivariate model, thirty one clinical or ergometric variables were statistically associated with PLVA and were included in the regression model. In the multivariate model, 13 of these variables were found to be statistically significant. A regression model (G) with a X(2) of 283.987 and a p<0.001, was constructed. Significant variables included: heart failure, antiarrhythmic drugs, myocardial lower-VD, age and use of digoxin, nitrates, among others.
  
  
  CONCLUSIONS
  This study allows clinicians to identify patients at risk of ventricular tachycardia or couplets during exercise, and to take preventive measures or appropriate supervision.
authors.affiliation: Cardiac Rehabilitation Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico. Electronic address: hermes_ilarraza@yahoo.com.
authors.forename: Ilarraza-Lomelí
authors.initials: IL
authors.lastname: Hermes
authors.affiliation: Cardiac Rehabilitation Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico.
authors.forename: García-Saldivia
authors.initials: GS
authors.lastname: Marianna
authors.affiliation: Cardiac Rehabilitation Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico.
authors.forename: Rojano-Castillo
authors.initials: RC
authors.lastname: Jessica
authors.affiliation: Hospital La Concepción, Saltillo, Coahuila, Mexico.
authors.forename: Barrera-Ramírez
authors.initials: BR
authors.lastname: Carlos
authors.affiliation: Cardiac Rehabilitation Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico.
authors.forename: Chávez-Domínguez
authors.initials: CD
authors.lastname: Rafael
authors.affiliation: Cardiac Rehabilitation Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico.
authors.forename: Rius-Suárez
authors.initials: RS
authors.lastname: María Dolores
authors.affiliation: Electrocardiology Department, National Institute of Cardiology Ignacio Chavez, Mexico City, Mexico.
authors.forename: Iturralde
authors.initials: I
authors.lastname: Pedro
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000009:adverse effects* / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Arrhythmia; Exercise test; Heart failure; Myocardial infarction; Sudden death