Surgical Volume-to-Outcome Relationship and Monitoring of Technical Performance in Pediatric Cardiac Surgery

A significant inverse relationship of surgical institutional and surgeon volumes to outcome has been demonstrated in many high-stakes surgical specialties. By and large, the same results were found in pediatric cardiac surgery, for which a more thorough analysis has shown that this relationship depends on case complexity and type of surgical procedures. Lower-volume programs tend to underperform larger-volume programs as case complexity increases. High-volume pediatric cardiac surgeons also tend to have better results than low-volume surgeons, especially at the more complex end of the surgery spectrum (e.g., the Norwood procedure). Nevertheless, this trend for lower mortality rates at larger centers is not universal. All larger programs do not perform better than all smaller programs. Moreover, surgical volume seems to account for only a small proportion of the overall between-center variation in outcome. Intraoperative technical performance is one of the most important parts, if not the most important part, of the therapeutic process and a critical component of postoperative outcome. Thus, the use of center-specific, risk-adjusted outcome as a tool for quality assessment together with monitoring of technical performance using a specific score may be more reliable than relying on volume alone. However, the relationship between surgical volume and outcome in pediatric cardiac surgery is strong enough that it ought to support adapted and well-balanced health care strategies that take advantage of the positive influence that higher center and surgeon volumes have on outcome.     

Dietary patterns and risk for Crohn's disease in children

BACKGROUND: Some dietary foods are considered protective (vegetables and fruits), whereas others (fatty foods) are thought to enhance the risk for Crohn's disease (CD). The evidence, however, is inconsistent. METHODS: We postulated that specific dietary patterns may influence the risk for CD. A case-control study was carried out. Newly diagnosed CD cases with population and/or hospital-based controls < or =20 years were selected from 3 tertiary hospitals across Canada. Pre-disease diet was assessed using a validated food frequency questionnaire (FFQ) administered within 1 month of diagnosis. Factor analyses and unconditional logistic regression (adjusted) was used to determine gender-specific dietary patterns and assess associated risks for CD. Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were estimated. RESULTS: A total of 149 cases and 251 controls were included. The mean age (range) of the cases was 13.3 (2.6-20 years). There were more boys (61.1%). Four dietary patterns each were observed among both boys and girls. Pattern 1 in girls, characterized by meats, fatty foods, and desserts, was positively associated with CD (OR 4.7, 95% CI 1.6-14.2). Pattern 2, common to both boys and girls, was characterized by vegetables, fruits, olive oil, fish, grains, and nuts and was inversely associated with CD in both genders (girls: OR 0.3, 95% CI 0.1-0.9; boys: OR 0.2, 95% CI 0.1-0.5). CONCLUSIONS: Our results suggest that specific dietary patterns could be associated with higher or lower risks for CD in children. Larger prospective studies are required to confirm these findings.     

Epstein-Barr virus-associated lymphoproliferative disease occurring in a patient with sarcoidosis treated by methotrexate and methylprednisolone

We describe the case of a 51-yr-old man with systemic sarcoidosis, complicated by the occurrence of a lymphoproliferative disease following a 36-month (duration) immunosuppressive treatment with methotrexate (MTX) and methylprednisolone. Four years after the onset of sarcoidosis, the patient presented a large necrotizing anal fistula. Pathological examination of this lesion showed a diffuse polymorphic infiltrate containing large Epstein-Barr virus (EBV)-positive lymphoid cells associated with areas of necrosis, all features similar to classical B-cell lymphoproliferative disorders occurring in immunosuppressed solid-organ recipients. MTX has been recently implicated in the development of lymphoproliferative disease in connective tissue diseases. This case supports the hypothesis that immunosuppression therapy may contribute to an increased risk for the development of EBV-associated lymphoproliferative disorders in patients suffering from sarcoidosis.     

Remodeling of sinus node function after catheter ablation of right atrial flutter

INTRODUCTION: The purpose of this study was to investigate the effect of ablation of right atrial flutter upon sinus node function in humans. METHODS AND RESULTS: This study enrolled 35 patients. Twenty-four patients (16 men and 8 women; age 68 +/- 11 years) were referred for ablation of persistent atrial flutter (duration 8 +/- 11 months). After ablation, there was abnormal sinus node function defined as a corrected sinus node recovery time (CSNRT) > or = 550 msec. The control group consisted of 11 patients who were undergoing pacemaker implantation for sinus node disease but did not have a history of atrial dysrhythmias or ablation. Within 24 hours of ablation or pacemaker implantation, baseline maximal CSNRT was measured through a permanent pacemaker by AAI pacing at six cycle lengths: 600, 550, 500, 450, 400, and 350 msec. CSNRT then was measured in the same manner at 48 hours, 14 days, and 3 months after ablation/pacemaker implantation. P wave amplitude and duration, and percent atrial sensing also were assessed at the same intervals. For patients undergoing atrial flutter ablation, there was progressive temporal recovery of CSNRT (1,204 +/- 671 msec at baseline vs 834 +/- 380 msec at 3 months; P < 0.001) and a significant increase in the percent atrial sensing and P wave amplitude at 3 months compared with baseline (P < 0.001). In control subjects, there was no change in the CSNRT, percent atrial pacing, or P wave amplitude. CONCLUSION: After ablation of persistent atrial flutter, there is temporal recovery of CSNRT and increase in spontaneous atrial activity. These findings suggest that atrial flutter induces reversible changes in sinus node function.     

Analysis of Th1 and Th2 cytokines expressing CD4+ and CD8+ T cells in rheumatoid arthritis by flow cytometry

OBJECTIVE: A Th1/Th2 cytokine imbalance with a predominance of Th1 cytokines has been suggested to be of pathogenetic importance in rheumatoid arthritis (RA). To evaluate the role of Th1/Th2 cytokines in RA, we used intracellular cytokine flow cytometry to determine cytokine profiles of CD4+ and CD8+ T cells in 34 peripheral blood (PB) and 10 synovial fluid (SF) samples from patients with RA. Results were compared with 10 PB samples from healthy controls (HC) and 5 SF samples from patients with non-RA synovitis. METHODS: After stimulating cells with PMA and ionomycin or alternatively with anti-CD3/CD28 in the presence of brefeldin A, intracellular levels of Th1 [interleukin 2 (IL-2), interferon-gamma (IFN-gamma)] and Th2 cytokines (IL-4, IL-5, IL-10, IL-13) were determined for CD3+CD8- (i.e., CD4+ Th1 and Th2 cells) and CD3+CD8+ (i.e., CD8+ Tc1 and Tc2 cells) T cells. RESULTS: The percentages of CD4+ and CD8+ Th1 and Th2 cytokines producing T cells (PB) were similar in patients with RA and healthy controls (HC), with a clear predominance of Th1 cytokines expressing, T cells. With regard to T cell subsets, IFN-gamma-producing T cells were significantly more frequently detected in the CD8+ subset [CD8+: median 45.1% (RA; p < 0.001), 38.2% (HC; p = 0.009) vs CD4+: 10.8%(RA), 17.0% (HC)]. Conversely, IL-2 was found in a higher percentage of CD4+ T cells [CD4+: median 33.4% (RA), 17.9% (HC) vs CD8+: 23.6% (RA), 12.3% (HC)]. Patients not in disease remission tended to have more IFN-gamma-producing CD8+ and IL-2-producing CD4+ T cells than patients in remission [CD8+: median 45.9% (IFN-gamma) vs 23.0% (IFN-gamma); CD4+: median 34.1% (IL-2) vs 18.2% (IL-2)1. In all PB samples, the proportion of T cells producing the Th2 cytokines IL-4, IL-5, IL-10, and IL-13 did not exceed 2%. Cytokine profiles did not differ between patients receiving immunosuppressive treatment and patients treated only with nonsteroidal antiinflammatory drugs. In comparison to PB, RA SF analysis revealed a significant increase in the percentage of IFN-gamma-producing CD4+ (p < 0.001) and CD8+ T cells (p < 0.001). In addition, the percentage of IL-10-producing CD4+ (p < 0.001) as well as CD8+ T cells (p = 0.001) was significantly elevated in SF. However, production of the other Th2 cytokines (IL-4, IL-5, IL-13) was similar in SF and PB. CONCLUSION: These data indicate similar cytokine profiles of T cells in PB of RA patients and healthy controls, with a strong predominance of Th1 cytokines producing T cells in the CD4+ and CD8+ T cell subset of both groups. PB cytokine profiles did not significantly differ in patients with active and non-active disease or between patients receiving and those not receiving immunosuppressive medication. In SF, the proportion of Th1 and Tcl cells was significantly elevated compared to PB, emphasizing the local importance of these cells for inflammation. CD8+ T cells (Tc1 cells) mainly contributed to the production of IFN-gamma, indicating an underestimated role of this cell subset for local cytokine production. The upregulation of IL-10-producing Th2 and Tc2 cells in SF may reflect an insufficient effort to down-regulate chronic inflammation in the joint. Modifying this cytokine imbalance in the joints may be a promising therapeutic approach in RA.     

Management of atrial fibrillation in the post-cardiac surgery setting

New onset postcardiac surgery AF is a prevalent problem associated with increased morbidity, hospital expense, and length of stay. Those agents that inhibit beta-adrenergic receptors (class II beta-blockers, sotalol, and amiodarone) have been demonstrated to be successful prophylaxis against postoperative AF. Furthermore, those therapies that do not inhibit beta-receptors are not effective prophylactic agents. Until comparative trials demonstrate a significant reduction in postoperative AF without additional adverse effects for sotalol or amiodarone compared with beta-blockers, class II beta-blockers are the preferred prophylactic therapy. If patients are deemed unable to take beta-blockers, amiodarone is likely the best alternative. Although prophylaxis against postoperative AF seems prudent, the impact of prophylactic therapy on length of stay and hospital costs has not been a primary objective of any randomized trial. Furthermore, no studies have compared prophylactic therapy for every patient versus therapy only for those patients who experience AF after heart surgery. In the absence of data from randomized clinical trials, postoperative AF should be managed in a similar fashion to clinical AF with attention to rate control, anticoagulation, and restoration of sinus rhythm.     

Adenosine triphosphate/adenosine guided pulmonary vein isolation does not improve the outcomes of ablation: a meta-analysis of randomized controlled trials

Background: Successful pulmonary vein isolation (PVI) is the most reliable predictor of success after ablation in patients with atrial fibrillation (AF). Adenosine triphosphate (ATP) unmasks the dormant conduction and can be used to improve the effectiveness of PVI. The impact of ATP guided PVI on clinical outcomes is discordant in various randomized controlled trials (RCTs).

Objectives: To delineate the incremental benefit of ATP during PVI in patients with AF through a meta-analysis.

Methods and results: Database searches through January 2017 identified 5 RCTs (enrolling 2839 patients) comparing ATP guided PVI versus standard PVI (non-ATP). Four trials exclusively studied paroxysmal AF while one trial included both paroxysmal and non-paroxysmal AF patients. Baseline characteristics, dose of adenosine and ablation strategies were clearly identified among all the trials. The risk ratio (RR) for AF episodes lasting >30 s after 3-month blanking period was calculated with random effects meta-analysis and showed no difference at a median follow up of 12 months [RR: 1.02, 95 % Confidence interval (CI): 0.85 to 1.25; p = 0.82]. Similarly, the number of repeat ablation was similar in both groups [RR: 1.02, 95 % CI: 0.63, 1.56; p = 0.98].

Conclusions: ATP guided PVI does not decrease the recurrence of AF or the need for repeat ablation at 12 months.     

Anesthesia for subcutaneous implantable cardioverter‐defibrillator implantation: Perspectives from the clinical experience of a U.S. panel of physicians

1 Background and objective

Worldwide adoption of the subcutaneous implantable cardioverter‐defibrillator (S‐ICD) for preventing sudden cardiac death continues to increase, as longer‐term evidence demonstrating the safety and efficacy of the S‐ICD expands. As a relatively new technology, comprehensive anesthesia guidance for the management of patients undergoing S‐ICD placement is lacking. This article presents advantages and disadvantages of different periprocedural sedation and anesthesia options for S‐ICD implants including general anesthesia, monitored anesthesia care, regional anesthesia, and nonanesthesia personnel administered sedation and analgesia.

2 Methods

Guidance, for approaches to anesthesia care during S‐ICD implantation, is presented based upon literature review and consensus of a panel of high‐volume S‐ICD implanters, a regional anesthesiologist, and a cardiothoracic anesthesiologist with significant S‐ICD experience. The panel developed suggested actions for perioperative sedation, anesthesia, surgical practices, and a decision algorithm for S‐ICD implantation.

3 Conclusions

While S‐ICD implantation currently requires higher sedation than transvenous ICD systems, the panel consensus is that general anesthesia is not required or is obligatory for the majority of patients for the experienced S‐ICD implanter. The focus of the implanting physician and the anesthesia services should be to maximize patient comfort and take into consideration patient‐specific comorbidities, with a low threshold to consult the anesthesiology team.