Dear Colleagues Hope you had a great Spring Break and back to the grind. In this issue of the journal we have several interesting original studies, case reports and review articles. Patten etal reviewed atrial fibrillation (AF) and hypertrophic cardiomyopathy (HCM) in a comprehensive fashion with greater depths of detail. Martin etal shared their 2-year outcomes on the ablation of complex fractionated electrograms. AF, characterized by rapid disorganized electrical activation of myocardium, is caused by and accompanied by remodeling of myocardial tissue. To explore this connection Buttner etal applied nonlinear optical microscopy (NLOM) to visualize typical myocardial features and atrial fibrillation effects in order to test a non-destructive imaging technology that in principle can be applied in vivo. Coherent anti-Stokes Raman scattering, endogenous two-photon excited fluorescence, and second harmonic generation were used to inspect unstained human atrial myocardium in patients who underwent surgical Cox-MAZE procedure with amputation of left atrial appendage. Development of in vivo application of the NLOM technique may represent a revolutionary approach in characterizing atrial fibrillation associated myocardial remodeling with important implications for therapy individualization and monitoring.