Dissertation: Epicardial ablation - a study evaluating thoracoscopic and surgical ablation procedures for patients with intractable atrial fibrillation

  • Date:
  • Location: Akademiska sjukhuset H:son Holmdahlsalen, Akademiska sjukhuset, ingång 100
  • Doctoral student: Johan Probst, Opponent: Rasmus Borgquist
  • Contact person: Carina Blomström-Lundqvist
  • Disputation

Johan Probst defends his thesis "Epicardial ablation - a study evaluating thoracoscopic and surgical ablation procedures for patients with intractable atrial fibrillation".

It is possible to view the dissertation through Zoom, https://uu-se.zoom.us/j/67350183587.

Abstract

Atrial fibrillation (AF) is a common condition, increasing in prevalence with age. Symptoms can be severe and quality of life is affected in patients suffering from AF. Treatment regimes aim to alleviate symptoms through rate or rhythm control. Rhythm control can be achieved effectively in early stages of AF with catheter ablation aiming for pulmonary vein isolation (PVI) however, in more advanced stages of the disease a surgical ablation is warranted if rhythm control is the goal.

The aim of this thesis was to evaluate the thoracoscopic epicardial left atrial surgical procedure for AF (TELA-AF) in patients suffering from highly symptomatic, mainly longstanding persistent AF (LPAF). The hypothesis was that TELA-AF would be effective in treating LPAF and that quality of life (QoL) would increase accordingly.

This thesis second hypothesis was that restoration of sinus rhythm would improve QoL in patients with permanent AF undergoing concomitant mitral valve surgery (MVS) and left atrial cryoablation compared to MVS alone.

The TELA-AF surgical technique included pulmonary vein isolation, left atrial "box-lesion" and partial vagal denervation. Patients were followed with clinical evaluation, seven-day Holter electrocardiogram, symptom severity questionnaire (SSQ)and a short form QoL questionnaire (SF-36), six and 12 months after surgery and again after ten years.

The concomitant MVS study was a sub-study of the randomized double-blinded SWEDMAF trial. Patients in permanent AF, accepted for MVS were randomized to MVS or MVS and cryo-ablation of the left atria. Patients self-reported QoL before and one year after surgery in the SF-36 questionnaire.

Twelve months after the TELA-AF procedure freedom from AF was 83 % although 12 % suffered from an iatrogenic atrial tachycardia post-surgery. The SSQ scores improved significantly from baseline. The SF-36 scores were similar to patients suffering from severe chronic disease at baseline but were not significantly different from an age-matched normal population at follow-up.

Ten years after surgery freedom from AF was 22 %, a significant reduction. Quality of life scores were however significantly better than baseline.

Patients randomized to concomitant surgery experienced a significant increase in QoL one year after surgery, but there was no difference in QoL scores compared to the MVS-alone group.

In conclusion, severe symptoms in AF patients translate to QoL scores as low as those observed in patients with severe chronic diseases. The TELA-AF procedure can alleviate AF related symptoms and improve QoL to the same level as a normal population in the short term. In the long term QoL can be maintained at a high level although displaying AF recurrence according to guidelines, challenging the concept of 30 seconds arrhythmia as a valid endpoint.

We could not show any benefit in a concomitant surgery for patients in permanent AF accepted for MVS. It is therefore important to balance the benefits and side effects in both short- and long-term perspective in order to justify the addition of a surgical AF ablation during MVS.