The use of two Comfort Young Child Formulas in the dietary management of toddlers with functional constipation: a randomized controlled trial.

BACKGROUND: Pharmacological intervention with laxatives is the conventional treatment for functional constipation (FC). Data to support the dietary management of FC is lacking. This study compared the efficacy of two Comfort young child formulas (YCFs) with regards to the maintenance of healthy stooling parameters in toddlers with a history of constipation. It was registered in the Netherlands Trial Registry [identifier: NL7420 (NTR7653)], registration date 20/09/2018. METHODS: Ninety-five healthy toddlers, aged 12 to 32 months, diagnosed with FC (Rome III criteria) were randomized to receive one of two study formulas after pharmacological treatment. For the first month of the intervention, subjects received a laxative in a decreasing maintenance dose alongside a test or control formula (maintenance phase). Subsequently, subjects only consumed formula for another month (post-maintenance phase). Stooling parameters were obtained weekly using the Bristol Stool Scale and the modified Rome III Questionnaire on Paediatric Gastrointestinal Symptoms for infants and toddlers. Differences in percentages of hard stools (primary outcome) and other stooling parameters were analysed using analysis of covariance and Chi-Square methods. RESULTS: Both formulas resulted in similar overall percentage of hard stools during the intervention period, respectively 5.02% in the test and 2.99% in the control group (n.s.). In the test group, percentages dropped from 7.11% at the end of the maintenance phase, to 3.92% at the end of the post-maintenance phase. In contrast, the percentage of hard stools in the control group was similar at the end of the maintenance (3.18%) and post-maintenance phase (2.83%; n.s.). No difference was found in the overall stool frequency between groups. At the end of the maintenance phase, only 22% and 19% of toddlers consuming the test and control formulae, respectively, met 2 or more of the criteria for FC. At the end of the study, this percentage of subjects decreased further to 9% in the test group, which tended to be lower compared to the 21% found in the control (p = 0.107). No laxative use was reported in either study group during the post-maintenance phase. CONCLUSION: Both Comfort YCF support the maintenance of improved stooling over time in toddlers with a history of constipation. The percentage of subjects suffering from functional constipation tended to be lower after the intervention period when receiving the formula with intact protein.

Atrial mapping during pulmonary vein pacing to detect conduction gaps in a second pulmonary vein isolation procedure.

BACKGROUND: Finding the conduction gaps in redo PV isolation procedures is challenging, and several maneuvers have been described. In the present study, we analyze the pace and map (P&M) maneuver [atrial mapping during pulmonary vein (PV) pacing] to locate the gaps in redo PV isolation procedures. METHODS: Consecutive patients undergoing a second PV isolation procedure at a single institution over a 4-year period were included. For the last 2 years, all the patients (n = 38) studied underwent PV isolation based on the P&M maneuver and were compared to the previous patients (n = 45). The atrial side of the ablation line was mapped with the ablation catheter during PV pacing, and the earliest site was considered a gap site. RESULTS: Shorter radiofrequency time was required to obtain PV isolation in the P&M group (485 ± 374 vs. 864 ± 544 s; p < 0.001), which remained significant after adjusting for the number of reconnected PVs (p = 0.01). We did not find significant differences in the procedure duration (106 ± 46 vs. 112 ± 53 min; p = 0.57) and arrhythmia recurrence during 1-year follow-up (26.6 vs. 28.9%; p = 0.82) after adjusting for several confounding factors (HR 1.32; 95% CI 0.5-3.4; p = 0.57). CONCLUSIONS: P&M is a simple maneuver to identify the gaps in ablation lines around the PV. It remains efficacious in redo procedures despite the difficulties in localizing the ablation lines performed in the first procedure. The P&M maneuver reduced the radiofrequency time required to isolate the PV without compromising the efficacy.

Relationship between left atrium catheter contact force and pacing threshold.

PURPOSE: The purpose of this study is to analyze the relationship between contact force (CF) and pacing threshold in left atrium (LA). METHODS: Six to ten LA sites were studied in 28 consecutive patients with atrial fibrillation undergoing pulmonary vein isolation. Median CF, bipolar and unipolar electrogram voltage, impedance, and bipolar and unipolar thresholds for consistent constant capture and for consistent intermittent capture were measured at each site. RESULTS: Pacing threshold measurements were performed at 188 LA sites. Both unipolar and bipolar pacing thresholds correlated significantly with median CF; however, unipolar pacing threshold correlated better (unipolar: Pearson R -0.45; p < 0.001; Spearman Rho -0.62; p < 0.001, bipolar: Pearson R -0.39; p < 0.001; Spearman Rho -0.52; p < 0.001). Consistent constant capture threshold had better correlation with median CF than consistent intermittent capture threshold for both unipolar and bipolar pacing (Pearson R -0.45; p < 0.001 and Spearman Rho -0.62; p < 0.001 vs. Pearson R -0.35; p < 0.001; Spearman Rho -0.52; p < 0.001). The best pacing threshold cutoff point to detect a good CF (>10 g) was 3.25 mA for unipolar pacing with 69% specificity and 73% sensitivity. Both increased to 80% specificity and 74% sensitivity for sites with normal bipolar voltage and a pacing threshold cutoff value of 2.85 mA. CONCLUSIONS: Pacing thresholds correlate with CF in human not previously ablated LA. Since the combination of a normal bipolar voltage and a unipolar pacing threshold <2.85 mA provide reasonable parameters of validity, pacing threshold could be of interest as a surrogate for CF in LA.

Atrial mapping during pulmonary vein pacing: a novel maneuver to detect and close residual conduction gaps in an ablation line.

BACKGROUND: Location of residual conduction gaps on ablation lines around pulmonary veins (PV) is challenging, and several maneuvers have been described. Atrial mapping during PV pacing-the "pace and map" maneuver-could localize gaps. METHODS AND RESULTS: We prospectively studied 209 patients undergoing PV isolation at a single institution over a 25-month period. In 24 (11.4 %) patients, 26 PV remained connected after an ablation line and an initial conventional gap closure protocol. The atrial side of the ablation line was mapped with the ablation catheter during PV pacing, and the earliest site was considered a gap site. Ablation at these gap sites resulted in bidirectional PV conduction block in 22 PV (85 %) in 21 patients (88 %), after 2.2 ± 1.6 radiofrequency applications and 8.2 ± 4.8 min. Early PV reconnection (≥20 min) occurred in 0 PV (0 %). During a mean follow-up of 12 ± 6 months, eight patients (33 %) had arrhythmia recurrences. CONCLUSIONS: The "pace and map" maneuver is a relatively simple and efficacious means to identify gaps in ablation lines around PV, focusing on the atrial rather than the PV side of the line. It could be considered among the ways to eliminate residual conduction gaps.