It is possible to predict mortality after ICD implantation?

Abstract

Abstract Introduction Implantable Cardioverter Defibrillators (ICD) therapy is not recommended in patients who do not have a reasonable expectation of survival for at least 1 year, although specific recommendations regarding clinical or functional status evaluation are lacking. Purpose To identify predictors of all-cause mortality in patients who implanted an ICD. Methods Prospective single-center study of patients who implanted ICD between 2015 and 2019. Clinical characteristics were evaluated at baseline and mortality was assessed using the national registry of citizens. We performed uni and multivariate analysis to compare clinical characteristics of patients who died and who survived using Cox regression and Kaplan-Meier methods. For the predictor creatinine, we assessed the discrimination power and the best cut-off using the area under the ROC curve (AUC) method. Results From 2015–2019, 414 ICDs were implanted (81% male, 62±12 years-old), and 50 (13%) of the patients died after a median follow-up of 23 [11–41] months. Patients who died during the follow-up were older (67±9 vs 61±12, p=0.002), had more diabetes (48% vs 33%, p=0.033) and a higher creatinine (1.23 [0.84–1.86] vs 1.00 [0.84–1.22], p<0.001). The remaining comorbidities were similar between groups (Fig. 1). Patients who died had more frequently an ICD implanted after complication associated with a previous device or as a pacemaker upgrade (6% vs 2%, p=0.030). They also had a higher frequency of ischaemic cardiomyopathy (i-CMP) (82% vs 56%, p=0.002) and of ejection fraction (EF) ≤50% (96% vs 82%, p=0.040). The best cut-off value of creatinine to predict mortality with a sensitivity of 65% and a specificity of 72% was 1.2mg/dl (AUC 0.650; CI95% 0.53–0.77). After adjusting for diabetes, i-CMP, EF ≤50% and upgrade/re-implantation after complication, we found that age (HR 1.033; 95% CI 1.00–1.06, p=0.041) and creatinine ≥1.2mg/dl (HR 2.134; 95% CI 1.09–4.19, p=0.028) were independent predictors of all-cause mortality. Conclusion In our cohort of patients who underwent ICD implantation for primary or secondary sudden cardiac death prevention, the all-cause mortality over a median follow-up period of 23 [11–41] months was 13%. We found that in addition to age, a baseline creatinine level ≥1.2mg/dl increases by 2-fold mortality in patients who undergo ICD implantation. Decisions regarding ICD candidacy should not be based on age alone but should also consider creatinine that predisposes to mortality despite ICD implantation. Funding Acknowledgement Type of funding sources: None. All cause mortality