Introduction:

implantable cardioverter defibrillator (ICD) has positively impacted the treatment of sudden cardiac death. However, appropriate or inappropriate shocks generate multiple adverse effects of diverse severity. Defining zones for therapies considering baseline pathology and using higher frequency ranges and longer detection times has been shown to decrease the number of therapies without increasing mortality. In Uruguay, there is no data on the impact of these programming changes on the incidence of appropriate and inappropriate shocks, nor have predictors of such events been evaluated.

Method:

observational retrospective cohort of 191 alive patients with ICD in the period from December 1991 to April 2016, at the Electrophysiology Service of Casa de Galicia. The implants were performedwith secondary prevention criteria in 82%. Mean age 55±16 y.o., predominantly male (78%). 46% of patientes had left ventricular ejection fraction (LVEF) >40% and 37% had ischemic heart disease. Cardiac resynchronization therapy (CRT) was associated in 20%. From 1/2013 the programming was adjusted to the current recommendations including 75 patients (39%). We considered the cumulative incidence of appropriate and inappropriate shocks and their association with programming through univariate analysis and binary logistic regression for the multivariate. We determined the incidence density and the density ratios between the two groups.

Result:

with a median follow-up of 3 years, the cumulative incidence of appropriate shocks was 31% (95% CI 24.4-37.9) and inappropriate shocks 17% (CI 95% 11.7-22.8%). With traditional programming, appropriate and inappropriate shocks were 40.5% and 23%, while with the new programming protocol it was 16% and 6.7% respectively. The predictors of inappropriate shocks identified were: appropriate shocks (OR 4.66 CI 95% 1.81-12 p=0.001) and traditional programming (OR 6.77 CI 95% 1.77-25.9 p = 0.005); For appropriate shocks the predictor was the traditional programming (OR 3.28 CI 95% 1.46-7.38 p = 0.002). The use of CRT (OR 0.036 IC95% 0.01-0.3 p = 0.002) was an independent protective factor. The incidence of inappropriate shocks is reduced by 27% with the current protocol while the incidence of appropriate shocks increases by 18%.

Conclusion:

the cumulative incidence of appropriate and inappropriate shocks is frequent in the studied population. The programming of the device according to current recommendations was significantly associated with less occurrence of inappropriate shocks. Traditional programming and appropriate shocks were independent predictors of inappropriate shocks while the use of CRT was independent predictor of appropriate discharges.

        · resumen en Español     · texto en Español     · Español ( pdf )