LAUSR

This editorial refers to the article published by Peix et al. titled ‘Value of intraventricular dyssynchrony assessment by gated-SPECT myocardial perfusion imaging in the management of heart failure patients undergoing cardiac resynchronization therapy (VISIONCRT)’ on the Journal of Nuclear Cardiology. This study shows the importance of the current problem in cardiac resynchronization therapy (CRT). In this study, we observe multiple variables that can affect the CRT response in clinical practice: patients with or without previous myocardial infarction, patients in ischemic cardiomyopathy phase, patients with or without myocardial ischemia, patients with or without coronary revascularization before gated SPECT study, patients with complete or incomplete revascularization, patients with or without myocardial viability criteria, patients with different large infarct size, patients with or without medical treatment optimizations during the follow-up, the cut-off value to define significant dyssynchrony, responder and non-responder patients, on-target group patients and off-target group patients, acquisition of images with different frames (8 or 16 frames), and different algorithms to guide left ventricular (LV) lead position placement, and the selected variables for the multivariate analysis. The importance of perspective and the future direction of intraventricular dyssynchrony assessment lies in the multiple variables that must be taken into account, and the fact that the heart failure (HF) represents a rapidly growing epidemic. Approximately 5.8 million patients in the United States currently suffer from HF, and over 670,000 of them are newly diagnosed with HF each year. Currently, the prediction is that in the United States by 2035, [ 9 million will have HF; the 5-year mortality after a diagnosis of HF is approximately 50%. Also, in United Kingdom, Conrad et al. 5 observed that from 2002 to 2014, HF incidence decreased, similarly for men and women. However, the estimated absolute number of individuals with newly diagnosed HF in the UK increased by 12% (from 170727 in 2002 to 190798 in 2014), largely due to an increase in population size and age. The estimated absolute number of prevalent HF cases in the UK increased even more, by 23% (from 750127 to 920616). The most important issue to be resolved in the future is, how to improve the criteria for cardiac resynchronization therapy (CRT)? Recently, Lyons et al. identified 25,102 hospitalizations for HF that included patients with a LV ejection fraction (LVEF) B 35% from 283 hospitals. Observed, that 49.1% (n = 12,336) of patients with HF, an LVEF B 35%, and no documented contraindication were eligible for CRT on the basis of historical guidelines (LVEF B 35%, QRS duration C 120 ms, and NYHA functional class III or IV), and 33.1% (n = 8299) of patients were eligible for CRT on the basis of current guidelines (LVEF B 35%, left bundle branch block [LBBB] with a QRS duration Reprint requests: Guillermo Romero-Farina, MD, PhD, FESC, FASNC, Cardiology Department, Hospital Universitari Vall d’Hebron, Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Paseo Vall d’Hebron 119-129, 08035 Barcelona, Spain; [email protected] J Nucl Cardiol 2021;28:65–71. 1071-3581/$34.00 Copyright 2019 American Society of Nuclear Cardiology.