Ne pacing (A) and during programmed ventricular stimulation (PVS) (B). Basic cycle length (S1 1) was 500 ms, respectively. (A) Action potential durations (APD) were measured from MAP onset to the 90 repolarization level (APD90). Diastolic interval (DI) span from APD90 of the preceding MAP to the onset of the current MAP. (B) MAP recordings were obtained during PVS using three extrastimuli. In this example, the first two extrastimuli (S2 and S3) were already delivered at the shortest coupling intervals (S1 2 235 ms, S2 3 218 ms), while the introduction of the third 11967625 extrastimulus (S4) was still in progress and the shortest possible S3 4 interval had not been reached yet. doi:10.1371/journal.pone.0054768.gResults Clinical findingsPatients of the two groups were predominantly male and had comparable LVEFs (ICM: 3267 ; DCM: 2869 ; p = 0.06) (Table 1). When compared with the DCM group, patients of the ICM group were significantly older. Digoxin use was significantly more Ipatasertib chemical information frequent in patients with DCM. In addition to the preexisting medication, amiodarone therapy was initiated later than the EP recordings in 15 patients (47 ) with ICM and in five patients (12 ) with DCM. Of the 26 TWA patients, 17 (65 ) were graded positive, 7 (27 ) negative, and 2 (8 ) indeterminate. Positive and indeterminate tests were grouped as non-negative.Baseline pacingAPD90 was prolonged along with the increase in BCL (274642 ms [600 ms] vs. 258635 ms [500 ms] vs. 237629 ms [400 ms] vs. 219624 ms [330 ms]; p,0.05 respectively). No significant differences could be found between the 2 recording sites (i.e. RVA vs. RVOT) or patient groups (i.e. ICM vs. DCM) with respect to all 4 BCLs. Figure 1A illustrates ventricular MAPs during baseline pacing at a BCL of 500 ms.Restitution slope of HMPL-013 supplier APDFigure 1B shows a representative example of MAP recordings during PVS using three extrastimuli (S2 4). A total of 282 APD90 restitution curves were constructed. A complete set of APD90 restitution curves from a stimulation site consisted of 3 curves each (S2, S3, and S4). Complete evaluation of three restitution curves (one set) originating from the RVA could be accomplished in all 74 study patients. At the RVOT, only 5 sets (16 ) were analyzable in the ICM group and 15 sets (36 ) in the DCM group (Table 2) due to instability 10457188 of signals and catheter. Figure 2 shows an example of six APD90 restitution curves in a given patient (two sets). Regression lines for the steepest segment are superimposed revealing a maximum slope 1 in each of the 6 curves. Maximum APD90 restitution slopes did not differ significantly between patients with ICM and those with DCM and there were no significant differences between RVA and RVOT (Table 2). The prevalence of maximum slope 1 was similar (mean average prevalence of 78 ) among both groups with no significant differences between the 2 recording sites or the 3 extrastimuli. NoInducibility at PVS and ICD treatmentSustained ventricular arrhythmias were inducible in 22/74 patients (30 ) (Table 1). Subsequent prophylactic ICD implantation was performed in 12/13 (92 ) of inducible and in 7 of noninducible ICM patients. In the DCM group, a total of 4 patients underwent ICD implantation, 3 of them were inducible. Eventually, therapy with amiodarone was administered to 16/19 (84 ) of ICD patients with ICM and 2/4 (50 ) with DCM. Restitution slopes for S2 (1.4160.65 vs. 1.5060.53; p = 0.51), S3 (1.3460.40 vs. 1.4360.48; p = 0.44) and S4 (1.3660.57 vs. 1.2860.53; p.Ne pacing (A) and during programmed ventricular stimulation (PVS) (B). Basic cycle length (S1 1) was 500 ms, respectively. (A) Action potential durations (APD) were measured from MAP onset to the 90 repolarization level (APD90). Diastolic interval (DI) span from APD90 of the preceding MAP to the onset of the current MAP. (B) MAP recordings were obtained during PVS using three extrastimuli. In this example, the first two extrastimuli (S2 and S3) were already delivered at the shortest coupling intervals (S1 2 235 ms, S2 3 218 ms), while the introduction of the third 11967625 extrastimulus (S4) was still in progress and the shortest possible S3 4 interval had not been reached yet. doi:10.1371/journal.pone.0054768.gResults Clinical findingsPatients of the two groups were predominantly male and had comparable LVEFs (ICM: 3267 ; DCM: 2869 ; p = 0.06) (Table 1). When compared with the DCM group, patients of the ICM group were significantly older. Digoxin use was significantly more frequent in patients with DCM. In addition to the preexisting medication, amiodarone therapy was initiated later than the EP recordings in 15 patients (47 ) with ICM and in five patients (12 ) with DCM. Of the 26 TWA patients, 17 (65 ) were graded positive, 7 (27 ) negative, and 2 (8 ) indeterminate. Positive and indeterminate tests were grouped as non-negative.Baseline pacingAPD90 was prolonged along with the increase in BCL (274642 ms [600 ms] vs. 258635 ms [500 ms] vs. 237629 ms [400 ms] vs. 219624 ms [330 ms]; p,0.05 respectively). No significant differences could be found between the 2 recording sites (i.e. RVA vs. RVOT) or patient groups (i.e. ICM vs. DCM) with respect to all 4 BCLs. Figure 1A illustrates ventricular MAPs during baseline pacing at a BCL of 500 ms.Restitution slope of APDFigure 1B shows a representative example of MAP recordings during PVS using three extrastimuli (S2 4). A total of 282 APD90 restitution curves were constructed. A complete set of APD90 restitution curves from a stimulation site consisted of 3 curves each (S2, S3, and S4). Complete evaluation of three restitution curves (one set) originating from the RVA could be accomplished in all 74 study patients. At the RVOT, only 5 sets (16 ) were analyzable in the ICM group and 15 sets (36 ) in the DCM group (Table 2) due to instability 10457188 of signals and catheter. Figure 2 shows an example of six APD90 restitution curves in a given patient (two sets). Regression lines for the steepest segment are superimposed revealing a maximum slope 1 in each of the 6 curves. Maximum APD90 restitution slopes did not differ significantly between patients with ICM and those with DCM and there were no significant differences between RVA and RVOT (Table 2). The prevalence of maximum slope 1 was similar (mean average prevalence of 78 ) among both groups with no significant differences between the 2 recording sites or the 3 extrastimuli. NoInducibility at PVS and ICD treatmentSustained ventricular arrhythmias were inducible in 22/74 patients (30 ) (Table 1). Subsequent prophylactic ICD implantation was performed in 12/13 (92 ) of inducible and in 7 of noninducible ICM patients. In the DCM group, a total of 4 patients underwent ICD implantation, 3 of them were inducible. Eventually, therapy with amiodarone was administered to 16/19 (84 ) of ICD patients with ICM and 2/4 (50 ) with DCM. Restitution slopes for S2 (1.4160.65 vs. 1.5060.53; p = 0.51), S3 (1.3460.40 vs. 1.4360.48; p = 0.44) and S4 (1.3660.57 vs. 1.2860.53; p.
