Risk Factors and Temporal Trends of Complications Associated With Transvenous Implantable Cardiac Defibrillator Leads

Prediction of mortality benefit based on periodic repolarisation dynamics in patients undergoing prophylactic implantation of a defibrillator: a prospective, controlled, multicentre cohort study

BACKGROUND

A small proportion of patients undergoing primary prophylactic implantation of implantable cardioverter defibrillators (ICDs) experiences malignant arrhythmias. We postulated that periodic repolarisation dynamics, a novel marker of sympathetic-activity-associated repolarisation instability, could be used to identify electrically vulnerable patients who would benefit from prophylactic implantation of ICDs by way of a reduction in mortality.

METHODS

We did a prespecified substudy of EUropean Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter Defibrillators (EU-CERT-ICD), a prospective, investigator-initiated, non-randomised, controlled cohort study done at 44 centres in 15 EU countries. Patients aged 18 years or older with ischaemic or non-ischaemic cardiomyopathy and reduced left ventricular ejection fraction (≤35%) were eligible for inclusion if they met guideline-based criteria for primary prophylactic implantation of ICDs. Periodic repolarisation dynamics from 24-h Holter recordings were assessed blindly in patients the day before ICD implantation or on the day of study enrolment in patients who were conservatively managed. The primary endpoint was all-cause mortality. Propensity scoring and multivariable models were used to assess the interaction between periodic repolarisation dynamics and the treatment effect of ICDs on mortality.

FINDINGS

Between May 12, 2014, and Sept 7, 2018, 1371 patients were enrolled in our study. 968 of these patients underwent ICD implantation, and 403 were treated conservatively. During follow-up (median 2·7 years [IQR 2·0-3·3] in the ICD group and 1·2 years [0·8-2·7] in the control group), 138 (14%) patients died in the ICD group and 64 (16%) patients died in the control group. We noted a 43% reduction in mortality in the ICD group compared with the control group (adjusted hazard ratio [HR] 0·57 [95% CI 0·41-0·79]; p=0·0008). Periodic repolarisation dynamics significantly predicted the treatment effect of ICDs on mortality (adjusted p=0·0307). The mortality benefits associated with ICD implantation were greater in patients with periodic repolarisation dynamics of 7·5 deg or higher (n=199; adjusted HR 0·25 [95% CI 0·13-0·47] for the ICD group vs the control group; p<0·0001) than in those with periodic repolarisation dynamics less than 7·5 deg (n=1166; adjusted HR 0·69 [95% CI 0·47-1·00]; p=0·0492; p_interaction=0·0056). The number needed to treat was 18·3 (95% CI 10·6-4895·3) in patients with periodic repolarisation dynamics less than 7·5 deg and 3·1 (2·6-4·8) in those with periodic repolarisation dynamics of 7·5 deg or higher.

INTERPRETATION

Periodic repolarisation dynamics predict mortality reductions associated with prophylactic implantation of ICDs in contemporarily treated patients with ischaemic or non-ischaemic cardiomyopathy. Periodic repolarisation dynamics could help to guide treatment decisions about prophylactic ICD implantation.

FUNDING

The European Community's 7th Framework Programme.

Iatrogeniа in internist practice

The article presents the history of the issue, the concept of iatrogenia, possible negative consequences of the interaction of the doctor and the patient in modern conditions. The main forms of iatrogenic (psychogenic, hospital, iatrogenic diagnostic procedures, medicinal, etc.) are given. An important place is occupied by implantation of iatrogenic (patients with artificial heart valves, cardio-implanted electronic devices, coronary stents, articular endoprostheses). The most vulnerable to the development of iatrogenic are elderly and senile patients. The interdisciplinarity of the iatrogenic problem and its educational significance for therapists, general practitioners, clinical pharmacologists, pathologists. Keywords: iatrogeniа, iatrogenic events, undesirable drug reactions, мedical error.

Healthcare utilization in patients with first-time implantable cardioverter defibrillators (data from the WEBCARE study)

BACKGROUND

Knowledge of the level of healthcare utilization (HCU) and the predictors of high HCU use in patients with an implantable cardioverter defibrillator (ICD) is lacking. We examined the level of HCU and predictors associated with increased HCU in first-time ICD patients, using a prospective study design.

METHODS

ICD patients (N = 201) completed a set of questionnaires at baseline and 3, 6, and 12 months after inclusion. A hierarchical multiple linear regression with three models was performed to examine predictors of HCU.

RESULTS

HCU was highest between baseline and 3 months postimplantation and gradually decreased during 12 months follow-up. During the first year postimplantation, only depression (β = 0.342, P = 0.002) was a significant predictor. Between baseline and 3 months follow-up, younger age (β = -0.220, P < 0.01), New York Heart Association class III/IV (β = 0.705, P = 0.01), and secondary indication (β = 0.148, P = 0.05) were independent predictors for increased HCU. Between 3 and 6 months follow-up, younger age (β = -0.151, P = 0.05) and depression (β = 0.370, P < 0.001) predicted increased HCU. Between 6 and 12 months only depression (β = 0.355, P = 0.001) remained a significant predictor.

CONCLUSIONS

Depression was an important predictor of increased HCU in ICD patients in the first year postimplantation, particularly after 3 months postimplantation. Identifying patients who need additional care and provide this on time might better meet patients' needs and lower future HCU.