HEMODYNAMIC DETERIORATION FOLLOWING RADIOFREQUENCY ABLATION OF THE ATRIOVENTRICULAR-CONDUCTION SYSTEM

Radiofrequency ablation of the atrioventricular conduction system (ACS ) has become an established therapy for patients with drug refractory atrial fibrillation. We observed eight patients with hemodynamic deter ioration after radiofrequency ablation of the atrioventricular conduct ion system. As we found hemodynamic deterioration related to worsening mitral regurgitation, we compared the clinical history, electrophysio logical, and echocardiographic data from the patients with hemodynamic deterioration and worsening mitral regurgitation (group 1) to those w ithout hemodynamic deterioration and stable mitral regurgitation after the procedure (group 2). Eight out of 108 patients (7.4%) undergoing ablation of the ACS deteriorated hemodynamically with acute pulmonary edema in three and congestive heart failure in five patients occurring at a mean of 3 and 8 weeks, respectively after the procedure. Three o f these patients were referred for mitral valve surgery. Two patients underwent ablation using a left-sided approach. A right-sided approach was used in five patients. In one patient, a left-and right-sided app roach was used. Compared to group 2 patients, group 1 patients had sig nificantly higher left ventricular end-diastolic diameters (64 +/- 6 m m vs 56 +/- 9 mm) at baseline despite similar fractional shortening (3 2% +/- 11% vs 34% +/- 13%), left ventricular end-systolic diameters (4 3 +/- 9 mm vs 36 +/- 7 mm) and degree of mitral regurgitation (1.4 +/- 1.1 vs 1.4 +/- 0.7) on echocardiographic analysis. Thus, hemodynamic deterioration together with progression of mitral regurgitation is a p otential complication of ablation of the ACS (up to 7.4%). Patients wi th high left ventricular end-diastolic diameters and moderate mitral r egurgitation at baseline seem prone to this complication.