Selecting persistent atrial fibrillation patients for pulmonary vein isolation based on the response to amiodarone: efficacy of the "one step back" strategy.

PURPOSE: Pulmonary vein isolation (PVI) by catheter ablation has reduced efficacy for the treatment of persistent atrial fibrillation (persAF), as compared to paroxysmal atrial fibrillation (paroxAF). We investigated whether the selection of persAF patients for PVI who "step back" to the paroxysmal stage on amiodarone offers a success rate comparable to that of patients with paroxAF. METHODS: Sixty-two consecutive persAF patients and 62 matched control patients with paroxAF were included. Persistent patients were started on amiodarone and cardioverted to sinus rhythm (SR). PVI was performed after 3 months in those who "stepped back" and had sustained SR and in all paroxAF patients. RESULTS: Five of the 62 (8%) study patients returned to persAF after cardioversion; despite amiodarone, they did not undergo PVI. The rest received PVI and was followed for a mean of 31 ± 14 months. Redo procedures were performed in 44% and 29% in the persAF and paroxAF group (p = 0.093), respectively. The recurrence rate after multiple procedures without antiarrhythmic drugs was similar among the persAF and paroxAF patients (11% and 7%) at 6 months (p = 0.510), but increased in the persAF group at 1 year (21% and 9%, p = 0.065) and exceeded that of the paroxAF group at the end of the follow-up (26% and 12%, p = 0.046). Kaplan-Meier survival analysis showed shorter time to recurrence in the persAF group (p = 0.045). CONCLUSION: PersAF patients who "step back" to the paroxysmal stage on amiodarone can expect long-term success of a PVI-only strategy in more than 70% of the time. However, late recurrences are more common compared to paroxAF.

Oxidative stress and antioxidant defense mechanism in glomerular diseases.

The changes in red blood cell (RBC) lipid peroxidation [measured via the malonyl dialdehyde (MDA) concentration], reduced (GSH), and oxidized glutathione (GSSG) levels, hemoglobin (Hb) oxidation and antioxidant enzyme [catalase (Cat), glutathione peroxidase, and superoxide dismutase (SOD)] activities were studied in 45 pediatric patients with various glomerular diseases [minimal change nephrotic syndrome (MCNS) in relapse or in remission, lupus nephropathy (SLE), poststreptococcal glomerulonephritis (APSGN), IgA nephropathy (IGA gn)], and in 20 adult patients with IGA gn and also in 15 pediatric and 14 adult controls. The in vitro effects of hydrogen peroxide [acetyl phenylhydrazine (APH) test] on the GSH and Hb metabolisms were likewise investigated. There was an increased oxidative stress in MCNS with relapse, IGA gn, SLE gn, and APSGN, which could be detected in the GSH and Hb oxidation and in the lipid peroxidation on the peripheral RBC-s. The RBC SOD and Cat activities were significantly lower in all patients than in the controls. The RBC GSSG level was significantly elevated in all patients, with the exception of MCNS in remission. This stimulated a compensatory GSH production in MCNS with relapse and in IGA gn, but not in SLE or APSGN. The regeneration of GSH from GSSG was reduced in MCNS with relapse, SLE, and IGA gn, but not in APSGN. In remission, the GSH-GSSG redox system normalizes, but in vitro the APH test stimulates an intensive Hb oxidation. In conclusion, there is a correlation between the presence of active glomerular disease and the evidence of oxidative changes in the various parameters measured in peripheral RBCs.