Efficacy and safety of cryoablation of para-Hisian and mid-septal accessory pathways using a specific protocol: single-center experience in consecutive patients.

PURPOSE: Radiofrequency (RF) catheter ablation of para-Hisian (P-H) and mid-septal (M-S) accessory pathways (APs) is a potentially harmful procedure due to their close location to the A-V node. Conversely, cryoablation (CA) appears safer in this setting. The aim of this study was to assess the efficacy and safety of CA of these APs using a specific protocol. METHODS: Fifty-three patients undergoing CA for P-H (45) or M-S (8) APs were included. CA was performed with a 4-mm catheter at - 75 °C for 480 s in the site where conduction block over the AP was obtained by a specific cryomapping protocol. Optimal catheter-tissue contact was achieved by inferior or superior vena cava approach. In case of failure, a 6-mm catheter and/or trans-septal catheterization (TSC) were considered. Normal AV conduction was monitored throughout CA, which was interrupted in case of its inadvertent modifications. RESULTS: In 46 patients (87%), CA was successful. Reasons for failure were as follows: lack of AP interruption (3 patients), intraprocedure AP conduction resumption (3), or transient A-H interval prolongation (1). Failure was associated with more aggressive approach including multiple procedures, greater use of 6-mm catheters, TSC, and longer CA applications. No major complications were observed. Three out of 46 patients (6.5%) experienced relapse of AP conduction during follow-up and were successfully re-treated by CA. CONCLUSIONS: CA of P-H and M-S APs is highly safe and effective and a specific protocol for cryomapping and CA could lead to a low recurrence rate at follow-up.

Risk factors for contrast induced nephropathy: a study among Italian patients.

This study aimed to make a profile of patients at highest risk of developing contrast induced nephropathy (CIN) in order to take appropriate prevention measures. 591 patients undergoing coronary procedures were divided into two groups: patients with (CIN-group) and without (no-CIN) an increase in creatinine level equal or more than 25% from baseline values within 24-48 h after the coronary procedure. All patients underwent an accurate anamnesis, objective exam, hematochemical measurements, and diagnostic exams. The results of this study while confirming that, average age (p = 0.01), diabetes mellitus (p < 0.0001), base line renal insufficiency (p = 0.0001), diuretic therapy (p = 0.002), higher contrast doses (p = 0.01), are associated with a higher risk of contrast-induced nephropathy, also demonstrated that both clinical (p = 0.01) and subclinical (p < 0.0001) atherosclerosis, and higher preprocedural high sensitive C-reactive protein levels (hs- CRP) (p = 0.02) are risk factors for CIN.