External validation and update of the J-ACCESS model in an Italian cohort of patients undergoing stress myocardial perfusion imaging

Abstract

Background Cardiovascular risk models are based on traditional risk factors and investigations such as imaging tests. External validation is important to determine reproducibility and generalizability of a prediction model. We performed an external validation of t the Japanese Assessment of Cardiac Events and Survival Study by Quantitative Gated SPECT (J-ACCESS) model, developed from a cohort of patients undergoing stress myocardial perfusion imaging. Methods We included 3623 patients with suspected or known coronary artery disease undergoing stress single-photon emission computer tomography (SPECT) myocardial perfusion imaging at our academic center between January 2001 and December 2019. Results In our study population, the J-ACCESS model underestimated the risk of major adverse cardiac events (cardiac death, nonfatal myocardial infarction, and severe heart failure requiring hospitalization) within three-year follow-up. The recalibrations and updated of the model slightly improved the initial performance: C-statistics increased from 0.664 to 0.666 and Brier score decreased from 0.075 to 0.073. Hosmer–Lemeshow test indicated a logistic regression fit only for the calibration slope (P = .45) and updated model (P = .22). In the update model, the intercept, diabetes, and severity of myocardial perfusion defects categorized coefficients were comparable with J-ACCESS. Conclusion The external validation of the J-ACCESS model as well as recalibration models have a limited value for predicting of three-year major adverse cardiac events in our patients. The performance in predicting risk of the updated model resulted superimposable to the calibration slope model.

Cardiovascular risk factors and development of nomograms in an Italian cohort of patients with suspected coronary artery disease undergoing SPECT or PET stress myocardial perfusion imaging

“…In fact, from models such as those obtained in this study, it is possible to perform external validations by multivariate logistic regression coefficients. The purpose of this technique is to verify whether a model is adaptable to other cohorts or from different countries from where it was obtained (22,23).…”

Age-Specific Cardiovascular Risk Factors for Major Adverse Cardiac Events in Patients Undergoing Myocardial Perfusion Imaging

“…In addition, although we included patients who were part of the ongoing prospective dedicated database, this is a retrospective study with all of the limitations inherent to retrospective investigations. Thus, the results may not be applicable in other study populations, as verified in some external validations performed for cardiovascular risk models [ 32 , 33 ]. Data related to follow-up such as cardiac events or mortality were not available on all patients undergoing MPI, who were not included in the study.…”

A cardiovascular risk model validated in Japan applied to an Italian cohort: Procedere con prudenza

“…In the present manuscript, 10 Drs. Petretta and Megna et al sought to externally validate the J-ACCESS risk estimation with an Italian cohort of 3623 patients who underwent nuclear stress testing between January 2001 and December 2019.…”