RESULTS	The VRR algorithm decreased rate variability ( RR30 : -7.36 + / - 8.8 ; P < 0.01 ) without increasing ventricular rate ( MR : -1.11 + / - 8.3 P = NS ) , while SLOPE improved significantly ( SLOPE : +15.41 + / - 16.8 P < 0.01 ) .\