The probability of subsequent low biventricular pacing percentage ( < 97 % ) was increased 3-fold ( odds ratio : 3.37 ; 95 % confidence interval : 1.74 to 6.50 ; p < 0.001 ) in patients with 0.1 % to 1.5 % ectopic beats and 13-fold ( odds ratio : 13.42 ; 95 % confidence interval : 7.02 to 25.66 ; p < 0.001 ) in patients with > 1.5 % ectopic beats compared with those with < 0.1 % ectopic beats .