Patient-related factors influencing management and procedural outcomes of de novo cardiac electronic device implantation

Abstract

Cardiac implantable electronic devices (CIED) are an essential part of the management of patients with life threatening arrhythmias. While many patient-related factors have been previously shown to play a role in the choice of CIED type offered to patients as well as outcomes of CIED implantation procedures, many patient characteristics remain understudied. Furthermore, little is known about the rates and causes of short-term readmissions after CIED implantation.
The present thesis provides answers to some of the gaps in evidence around the relationship between several patient related factors and the management as well as outcomes of CIED implantation as a de novo procedure.
The first phase, presented in Chapter 4, examined patient characteristics that predict the choice of cardiac resynchronisation therapy (CRT) device offered to patients with severe left-sided heart failure. Factors such as patient sex, history of ventricular arrhythmias, active malignancy and renal failure were among the strongest predictors of the type of CRT offered to patients.
The second phase, which is discussed in Chapters 5 to 8 of this thesis, focused on the impact of several patient related factors on in-hospital outcomes after CIED implantation, including mortality and procedure-related complications (thoracic, cardiac and bleeding). Females were associated with worse in-hospital outcomes, despite adjustment for multiple confounders, as were patients with active cancer and intermediate to high-risk frailty. While the overall burden of comorbidity correlated with increased odds of in-hospital mortality and acute stroke, it did not confer worse procedure-related outcomes.
The third and final phase, in Chapter 9 of the thesis, looked at the rates and causes of 30- day readmissions after CIED implantation and showed that these were common (1 in 7 patients), with a significant proportion being due to cardiac and device-related causes. In the relevant chapter, I report several important patient characteristics that are predictive of 30-day cardiac readmission.
In my discussion, I reflect on the clinical implications of my findings including the need for risk scoring systems that incorporate the patient-related factors studies in this thesis as well as risk reduction technical strategies to address the inherent risk of procedural complications in certain high-risk patient groups.