Patients with atrial fibrillation undergoing coronary artery bypass grafting have a higher survival advantage if they received surgical ablation during the procedure compared to patients who did not, according to a study published June 3 in the Annals of Thoracic Surgery.
Despite this advantage, only 22% of Medicare patients with preexisting atrial fibrillation who underwent CABG received surgical ablation between 2008 and 2019, with only 27% of patients receiving surgical ablation in 2019.
Justin Schaffer, MD, medical director of surgical outcomes at Baylor Scott & White The Heart Hospital and the study’s lead author, shared with Becker’s what the findings mean for clinical guidance and why ablation remains underutilized.
Editor’s note: Responses have been lightly edited for clarity and length.
Question: Your study found a significant survival benefit linked to surgical ablation during CABG, yet only 1 in 4 eligible patients received surgical ablation in 2019. What are the main barriers preventing more widespread adoption?
Dr. Justin Schaffer: A study was performed by Dr. Mehaffey [James Mehaffey, MD, co-director of research in the division of cardiac surgery at Morgantown, W.Va.-based WVU Heart & Vascular Institute] and colleagues that attempted to tackle this very question.
Performing surgical ablation at the time of CABG or valvular heart surgery adds additional surgical time. This includes both time on the heart-lung machine as well as cross-clamp time. Additional time on the heart-lung machine and/or cross-clamp time where the heart is ischemic may increase operative risk.
Notably, several studies have noted minimally different operative risk when ablation is added to cardiac surgery. However, the additional interventions may still be perceived as adding risk to the surgery, and this, in my opinion, likely represents the largest factor why ablation is infrequently performed in patients with preexisting atrial fibrillation.
Q: How can health systems work to overcome them?
JS: Surgical ablation during cardiac surgery requires capital expenditure by health systems.
Surgeons require a functioning “ablation generator” and/or “cryothermy generator” to create the “burn” or “freeze” lines used during the procedure. Aside from ensuring that these surgical ablation platforms are available to their cardiac surgeons, health systems can have an open conversation with surgeons regarding whether other barriers — OR staffing issues, surgeon concerns regarding operative risk, lack of conviction regarding efficacy of ablation therapies, etc. — underlie their decisions to withhold ablation therapies in patients with preexisting atrial fibrillation.
Q: What are the potential downstream benefits of surgical ablation during CABG that hospital administrators should be aware of in the context of population health and outcomes-based care?
JS: Our analysis focused on survival as an endpoint, so we can only hypothesize regarding the mechanism by which surgical ablation during CABG improves outcomes in patients with preexisting atrial fibrillation.
However, randomized studies have clearly demonstrated a reduction in the prevalence of atrial fibrillation if surgical ablation is performed at the time of cardiac surgery in patients with preexisting atrial fibrillation. This reduction in the burden of atrial fibrillation may help prevent tachycardia-related patient readmissions, which we imagine would be of interest to hospital administrators. Fewer readmissions after cardiac surgery is an endpoint everyone can get excited about.
We also hypothesize that over the long term, patients with preexisting atrial fibrillation who undergo surgical ablation may be subject to fewer tachyarrhythmia-related heart failure episodes which often result in hospital admission, and that is this reduction in tachyarrhythmia-related heart failure is what ultimately leads to the improved late survival in ablation recipients.
Q: What long-term value considerations should leaders take into account in terms of financial investment and operational strategy?
JS: To be frank, we are under-educated regarding the financial implications of supporting a surgical ablation program at the hospital level. However, given The Society of Thoracic Surgeons’ Class I indication for surgical ablation as well as left atrial appendage exclusion at the time of cardiac surgery, and the growing body of evidence noting improved late survival in ablation recipients, we believe that essentially all cardiac surgical centers should be able to offer their patients surgical ablation for patients with preexisting atrial fibrillation.
