CKD accelerates recurrence of ventricular tachyarrhythmias in ICD recipients
Chronic kidney disease (CKD) appears to increase the rate of recurrent ventricular tachyarrhythmia in recipients of implantable cardioverter defibrillators (ICDs), according to a recent study.
“The present study evaluates the prognostic impact of CKD on recurrences of ventricular tachyarrhythmias, device-related therapies, rehospitalization and all-cause mortality at 5 years of follow-up in consecutive ICD recipients surviving episodes of ventricular tachyarrhythmias,” said researchers.
Of the 585 consecutive ICD patients included, majority did not have CKD (57 percent; n=333; median age, 56 years; 79 percent male). The remaining 43 percent did (n=252; median age, 56 years; 80 percent male). After propensity score matching, 218 non-CKD and 217 CKD participants were left. Most of the participants had an activated transvenous ICD. [Heart Vessels 2019;doi:10.1007/s00380-019-01415-z]
Over a follow-up period of 5 years, 50 percent of all CKD patients developed the primary endpoint of first recurrence of ventricular tachyarrhythmias. This was significantly higher than that in non-CKD participants (40 percent; log-rank p=0.008), leading to a significant difference in calculated risk (hazard ratio [HR], 1.398; 95 percent CI, 1.087–1.770; p=0.009).
The above trend remained regardless of whether ICD was a primary (HR, 1.468; 0.986–2.186; p=0.059) or secondary (HR, 1.306; 0.959–1.778; p=0.090) preventive ICD indication.
In terms of secondary endpoints, patients with CKD were significantly less likely to experience freedom from first appropriate device therapy (41 percent vs 30 percent; log-rank p=0.002; HR, 1.532; 1.163–2.018; p=0.002). All-cause mortality was likewise significantly elevated in CKD participants (30 percent vs 14 percent; p=0.001; HR, 2.451; 1.707–3.519; p=0.001).
No such between-group differences were observed in terms of recurrence of inappropriate device therapies.
However, multivariable adjusted Cox regression analysis showed that CKD did not significantly increase the risk of first-recurrence ventricular tachyarrhythmia (HR, 1.201; 0.921–1.568; p=0.177). This was further reflected in the matched cohort (41 percent vs 48 percent; p=0.111). The secondary outcome of recurrence of appropriate device therapy remained borderline significant (39 percent vs 33 percent; log-rank p=0.076; HR, 1.329; 0.865–1.823; p=0.077).
“This observational and retrospective registry-based analysis reflects a realistic picture of consecutive healthcare supply of high-risk patients presenting with ventricular tachyarrhythmias,” said researchers, noting that attrition over the follow-up period was minimal and that all included information were reliably documented by attending cardiologists.
However, CKD was assessed only upon patient presentation, and no subsequent evaluations were obtained during follow-up. This necessitates further validation in larger, more representative samples, with a special focus on the effect of CKD in selected patient subgroups.
“Whether CKD patients may significantly benefit from ICD implantation is still unclear, even when focusing on primary or secondary preventive indication,” said researchers. “It may be speculated whether the risk of device-related complications may justify the potential, not yet proven, benefits for the prevention of ventricular tachyarrhythmias in CKD patients compared to the general population.”
“Accordingly, the present study contributes to a better understanding of this important high-risk subgroup. The use of epicardial or subcutaneous leads may further prevent central venous thrombosis and device-related infections in future,” they added.