QTc Interval Predicts Outcome of Catheter Ablation in Paroxysmal Atrial Fibrillation Patients with Type 2 Diabetes Mellitus

Catheter ablation has been recommended as a treatment option for paroxysmal atrial fibrillation（PAF） patients complicated with type 2 diabetes mellitus（T2DM）. PAF patients with T2 DM have a higher recurrence rate after catheter ablation. Prolongation of corrected QT（QTc） interval has been linked to poor outcomes in T2 DM patients. Whether the abnormal QTc interval is associated with the ablation outcome in the PAF patients with T2 DM remains unknown. In this study, 134 PAF patients with T2 DM undergoing primary catheter ablation were retrospectively enrolled. Pre-procedural QTc interval was corrected by using the Bazett＇s formula. Cox proportional hazards models were constructed to assess the relationship between QTc interval and the recurrence of AF. After a 29.1-month follow-up period, 61 patients experienced atrial tachyarrhythmia recurrence. Recurrent patients had a longer QTc interval than non-recurrent patients（425.2±21.5 ms vs. 414.1±13.4 ms, P=0.002）. Multivariate Cox regression analysis revealed that QTc interval [hazard ratio（HR）=1.026, 95% confidence interval（CI） 1.012–1.040, P=0.005] and left atrial diameter（LAD）（HR=1.125, 95% CI 1.062–1.192, P=0.003） were independent predictors of recurrent atrial tachyarrhythmia. Receiver operating characteristic analysis demonstrated that the cut-off value of QTc（418 ms） predicted arrhythmia recurrence with a sensitivity of 55.7% and a specificity of 69.9%. A combination of LAD and QTc was more effective than LAD alone（P〈0.001） in predicting arrhythmia recurrence after the procedure. QTc interval could be used as an independent predictor of arrhythmia recurrence in T2 DM patients undergoing AF ablation, thus providing a simple method to identify those patients who likely have a better outcome following the procedure.

Up to Date Management of DCIS and Future Directions

Ductal carcinoma in situ (DCIS) is a non-invasive malignancy confined within the basement membrane of the breast ductal system. There is a lot of disparity in the natural history of DCIS with an estimated incidence of progression to invasive ductal carcinoma between 20% to 53% over ten or more years after initial diagnosis. The surgical and adjuvant management of DCIS has advanced significantly in the last couple of decades. Nonetheless, surgeons, medical oncologists, and radiation oncologists, along with their patients, still depend on conventional clinical and pathologic risk factors to make management decisions. Irrespective of the management strategy, long-term survival is excellent. The debate around DCIS relates to preventing either under-treatment or over-treatment. In this paper, we will review the incidence and management options of DCIS. Additionally, we will focus on several current disputes related to the management of DCIS, including breast conserving surgery, the role of radiation in breast conservation surgery, sentinel node biopsy in DCIS, hormonal therapy, various risk stratification schemes, and the option of active surveillance for low-risk DCIS.