Statistical analyses
Data are reported as the means ± standard errors of the means (SEMs).
Statistical analysis was performed using IBM SPSS Statistics for Windows
(version 20.0, IBM, New York, USA). The concentration-response
relationships were analyzed using GraphPad Prism for Windows (version
6.02, GraphPad Software, Inc., San Diego, CA). When control/baseline and
treatment values were obtained from the same heart/cell, the
significance of the differences in the measures before and after
interventions was determined by repeated measures one-way ANOVA followed
by the Newman-Keul test. The χ2 test and Fisher’s test
were used to compare the incidences of atrial arrhythmias and trigger
activities. Differences were considered significant at p <
0.05.