Mid-term results of endoscopic mitral valve repair in combination with endocardial or epicardial ablation

A systematic review of surgical ablation versus catheter ablation for atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is an increasingly prevalent condition in the ageing population, with significantly associated morbidity and mortality. Surgical and catheter ablative strategies both aim to reduce mortality and morbidity through freedom from AF. This review consolidates all currently available comparative data to evaluate these two interventions.

METHODS

A systematic search was conducted across MEDLINE, PubMed, Embase, Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews from January 2000 until August 2013. All studies were critically appraised and only those directly comparing surgical and catheter ablation were included.

RESULTS

Seven studies were deemed suitable for analysis according to the inclusion criteria. Freedom from AF was significantly higher in the surgical ablation group versus the catheter ablation group at 6-month, 12-month and study endpoint follow-up periods. Subgroup analysis demonstrated similar trends, with higher freedom from AF in the surgical ablation group for paroxysmal AF patients. The incidence of pacemaker implantation was higher, while no difference in stroke or cardiac tamponade was demonstrated for the surgical versus catheter ablation groups.

CONCLUSIONS

Current evidence suggests that epicardial ablative strategies are associated with higher freedom from AF, higher pacemaker implantation rates and comparable neurological complications and cardiac tamponade incidence to catheter ablative treatment. Other complications and risks were poorly reported, which warrants further randomized controlled trials (RCTs) of adequate power and follow-up duration.

Impact of epicardial ablation of concomitant atrial fibrillation on atrial natriuretic peptide levels and atrial function in 6 months follow-up: does preoperative ANP level predict outcome of ablation?

Background

Epicardial ablation concomitant to cardiac surgery is an easy and safe approach to treat atrial fibrillation (AF), but its efficacy in longstanding persistent (LsPe) AF remains intermediate. Although larger left atrial size has been associated with worse outcome after ablation, biochemical predictors of success are not well established. The aim of this study was to evaluate relationship between biochemical marker, echo-characteristic and cardiac rhythm in 6 months follow-up after epicardial ultrasound (HIFU) ablation.

Methods

We included 78 consecutive patients, who underwent elective cardiac surgery. 42 patients with AF (11.9% paroxysmal, 23.8% persistent, 64.3% LsPeAF) underwent concomitant HIFU ablation (AF ablation group), 16 with AF underwent cardiac surgery without ablation (AF control) and 20 had preoperatively normal sinus rhythm (SR control). We measured plasma ANP secretion before, on postoperative day (POD) 1, POD 7 as well as 3 and 6 months after surgery. Moreover, we estimated cardiac rhythm and atrial mechanical function by Atrial Filling Fraction (AFF) and A-wave velocity in follow-up.

Results

Baseline ANP levels were higher in patients with LsPeAF, as compared to the paroxysmal and permanent AF and to the SR control group. Patients with LsPeAF (n = 27) who converted to SR had preoperatively smaller left atrial diameter (LAD) and LA area (p < 0.05) and higher ANP level (p = 0.009) than those who remained in AF at 6 months after ablation. Multivariate regression analysis revealed that only preoperative ANP level was an independent predictor of cardiac rhythm after ablation. Patients with LsPeAF and preoperative ANP >7.5 nmol/l presented with SR in 80%, in contrast to those with ANP <7.5 nmol/l who converted to SR in 20%. We detected gradual increase of AFF and A-velocity at 6 months after ablation (p < 0.05) solely in AF ablation group. ANP levels were increased on POD 1 in ablation group (p < 0.05), without changes in further follow-up.

Conclusion

Our results indicate that preoperative ANP levels may be a new biochemical predictor of successful epicardial ablation in patients with concomitant LsPeAF. HIFU ablation caused a significant improvement of atrial mechanical function and gradual increase of AFF and did not associate with alteration of atrial endocrine secretion at 6 months follow-up.

Positioning of the ablation catheter in total endoscopic ablation

Minimally invasive ablation of atrial fibrillation is an option in patients not suitable for or refractory to catheter ablation. Total endoscopic ablation can be performed via a monolateral approach, whereby a left atrial box lesion is created. If the ablation is introduced from the right side, the positioning of the ablation catheter on the partly hidden left pulmonary veins is of vital importance. Using thoracoscopy in combination with multiplane transoesophageal echocardiography, the anatomical position of the ablation catheter can be established. Our experience in over 60 procedures has confirmed this to be a safe technique of total endoscopic ablation.