The CAVIAR response score accurately predicts long term survival after cardiac resynchronisation therapy
W Gerrits, C S L Chiu, P C Wouters, M J M Cramer, M Guglielmo, F J Van Slochteren, A H Maass, L Smit, K Vernooy, A M W Van Stipdonk, G Heltzel, F J De Lange, L Hopman, M Rienstra, M MeineAbstract
Background
In the MArkers and Response to Cardiac resynchronisation therapy (MARC) study predictors of response to cardiac resynchronisation therapy (CRT) were studied. The CRT-Age-Vectorcardiographic QRSAREA-Interventricular mechanical delay-Apical Rocking (CAVIAR) response score was designed and found to predict echocardiographic CRT response as well as short-term (<1 year) heart-failure hospitalisations and all-cause mortality. The MARC-Long-Term Outcome (LTO) extension of the study provides long-term follow-up of this CRT cohort.
Objective
To evaluate the association between the baseline CAVIAR response score and long-term (10 years) survival after CRT.
Methods
In the MARC study, patients received a CRT device between 2012 and 2013 according to guideline indications at the time. The CAVIAR score, consisting of a patients’ age, QRSAREA, apical rocking, and interventricular mechanical delay, was calculated at baseline and divided into tertiles: -1 to 1, 2 to 4, and 5 to 9. CRT response at six months was defined as ≥15% left-ventricular end-systolic volume reduction indexed to body-surface area on echocardiography. Patients’ electronic records were reviewed for survival status. Kaplan–Meier (KM) analysis, Cox regression, and receiver-operating-characteristic (ROC) curve analysis with corresponding area under the curve (AUC) values were performed at 5- and 10-year follow-up. The CAVIAR score tertile was analysed as an ordinal and categorical variable.
Results
Of 240 patients in de MARC study, data for 224 (93%) were available for LTO analysis. Median follow-up was 9.0 years (interquartile range 5.3-11.6). Mean age was 66 ± 10 years, 36% were women, 62% had left bundle branch block (LBBB), and 42% had an ischaemic cardiomyopathy (ICM). All-cause mortality was 23% at 5 years and 47% at 10 years. KM curves showed significantly better survival in higher CAVIAR tertiles (Figure 1). Unadjusted hazard ratios at 5- and 10-year follow-up showed that higher CAVIAR tertiles and CRT response were associated with a significantly lower risk of mortality (Table 1). In multivariable models (adjusted for LBBB, ICM, CRT response and CAVIAR score tertile), both higher CAVIAR tertile and CRT response remained independently associated with improved survival, whereas LBBB and ICM were not (data not shown). The CAVIAR tertile 5–9 vs –2 to 1 showed the greatest survival benefit (adjusted HR 0.26 at 10 years). ROC analysis demonstrated greater discriminative ability for the CAVIAR score (AUC 0.72 at 5 years and 0.71 at 10 years).
Conclusion
The four-variable CAVIAR response score, calculated at baseline, demonstrated an independent association with long-term survival after CRT and provided incremental discrimination beyond traditional markers such as LBBB and ICM.The CAVIAR score and Kaplan-MeierPredictors of all-cause mortality