Background The study was to access the feasibility and effectiveness of permanent left bundle branch pacing(LBBP)in patients with bradycardia after cardiac surgery,in comparison with conventional right ventricular out...Background The study was to access the feasibility and effectiveness of permanent left bundle branch pacing(LBBP)in patients with bradycardia after cardiac surgery,in comparison with conventional right ventricular outflow tract septal pacing(RVOSP).Methods A total of 50 patients with cardiac surgery who underwent permanent pacemaker implantation(PPI)were enrolled,21 patients underwent LBBP(LBBP group)and 29 patients underwent RVOSP(RVOSP group).Pacing electrical parameters,QRS duration(QRSd),echocardiographic measurements,lead and device related complications were obtained at procedure and during follow-ups.Results There were no statistically significant differences between the LBBP group and the RVOSP group at procedure and at the twelfth month’s follow-up in pacing thresholds(0.64±0.16 V vs.0.63±0.22 V)and(0.91±0.28 V vs.0.85±0.20 V),R-wave amplitude(16.68±4.52 mV vs.15.09±4.53 mV)and(14.41±8.65 mV vs.12.65±6.17 mV),pacing impedances(719.24±152.65Ωvs.639.13±177.04Ω)and(534.01±96.92Ωvs.499.18±77.87Ω).But the average ventricular pacing percentage(VP%)at the first month’s follow-up(81.96±32.06%vs.58.37±42.96%)and at the twelfth month’s follow-up(84.65±35.84%vs.53.57±38.47%)showed significant difference between two groups(P<0.05);The LBBP group produced narrower QRSd(121.13±23.91 ms)than the RVOSP group(158.00±9.69 ms)(P=0.011).There were no significant differences between the LBBP group and the RVOSP group at pre-procedure and at the twelfth month’s follow-up in echocardiographic parameters,which included left ventricular end-diastolic dimension(LVEDD)(48.76±7.08 mm vs.47.34±6.91 mm)and(50.58±10.33 mm vs.45.97±7.11 mm),left ventricular ejection fraction(LVEF)(58.33±12.64%vs.61.50±8.40%)and(55.85±16.35%vs.61.50±10.52%),and area of tricuspid regurgitation(TR)(2.79±3.65 cm2 vs.2.85±2.26 cm2)and(3.09±2.34 cm2 vs.2.95±1.92 cm2).No lead and device related complication was observed during follow-ups.Conclusions LBBP is feasible and effective in patients with bradycardia after cardiac surgery.LBBP produces narrow QRSd,which may be a preferred pacing strategy for patients after cardiac surgery.[S Chin J Cardiol 2021;22(1):13-20]展开更多
Background There is little information on the factors that have influenced the long-term success rate of radiofrequency ablation of ventricular arrhythmias(VAs)at different targets.The objective of this study was to i...Background There is little information on the factors that have influenced the long-term success rate of radiofrequency ablation of ventricular arrhythmias(VAs)at different targets.The objective of this study was to investigate the characteristics of the ablation of VAs and the factors influencing the long-term success rate in our center.Methods Totally,2751 consecutive patients(mean ages 44±15 years,male/female 58.6%/41.4%)with VAs underwent radiofrequency ablation in Guangdong Provincial People’s Hospital from 2013 to 2018 were analyzed.Baseline data were retrieved from the medical record system.Long-term follow-up data were obtained by telephone interview.We mainly recorded the patient’s last post-ablation holter,and the symptoms after ablation.Multivariable regressions were applied to assess the relationship between the long-term success rate and the influence factors.Results Through the baseline data of 2751 patients,we found that the acute success rate of ablation was 95.1%.The average follow-up time was 16±5 months(ranging from 1 to 80).In all,304 patients(11%)lost follow-up,while 2447 patients(89%)were successfully followed.The long-term success rate of ablation was 82.56%.By means of multivariable regression analyses,it was discovered that cardiovascular diseases,such as coronary heart disease(OR:0.568,95%CI:0.327-0.987),hypertension(OR:1.554,95%CI:1.100-2.198),were independently associated with the long-term success rate,as well as ablation approaches(OR:0.212,95%CI:0.082-0.550).Lower ablation success rates of the patients whose VAs were originated from some uncommon region,like left ventricular papillary muscle,Summit,etc.were observed.Conclusions Ablation approaches,concomitant cardiovascular diseases,and ablation targets were related to the long-term clinical outcome of VAs ablation.展开更多
Backgrounds Whether the contact force(CF)-sensing catheter could improve the efficiency of pace mapping(PM)in right ventricle outflow tract(RVOT)has not been fully studied.The present study was the first investigation...Backgrounds Whether the contact force(CF)-sensing catheter could improve the efficiency of pace mapping(PM)in right ventricle outflow tract(RVOT)has not been fully studied.The present study was the first investigation of the CF distribution in the right ventricle(RV)by using a CF-sensing catheter and the relationship between CF and capture threshold in RVOT.Methods In total,4543 mapping points with CF were recorded in 15 patients.Operators were blinded to CF data and data were analyzed according to 10 predefined RV segments.PM were performed at 6 different RVOT segments with 3 different intentional CF levels and 3 different pacing setup.The pacing threshold in RVOT and pacing capture level were recorded.The morphology matching score were recorded and analyzed.Results Median CF during RV mapping was 8(5-12)g and coefficient of variation was 71.64%.Median CF ranged from 9.5(5.8-16)g at the posterior-outflow tract freewall(OTFW)to 7(4-10)g at the apex.Distribution of CF≥20 g in RV predefined segments mainly located in the OTFW.Distribution of CF≤2 g in RV predefined segments mainly located in the inflow tract freewall(ITFW),anterior-OTFW,and apex.A total of 810 pacing were performed at RVOT with different CF and output.Stable capture rate could be significantly improved via increasing CF level under 2 mA output(46.7%/2-5 g vs.50%/6-9 g vs.91.1%/≥10 g),and no capture rate could be significantly declined simultaneously(16.7%/2-5 g vs.8.9%/6-9 g vs.2.2%/≥10 g).Conclusions A marked variability in CF was observed among the different predefined segments.CF mapping could improve the safety and efficacy of catheter ablation of premature ventricular contraction(PVC)/ventricular tachycardia(VT)in RV.CF was an essential factor in RVOT pace mapping process,especially under low-pacing output.[S Chin J Cardiol 2021;22(1):21-29]展开更多
Background Atrial tachycardia(AT)with cycle length(CL)alternans is uncommon and conventional mapping of this AT remains challenging. We used an ultrahigh density mapping system to rapidly map complicated circuits with...Background Atrial tachycardia(AT)with cycle length(CL)alternans is uncommon and conventional mapping of this AT remains challenging. We used an ultrahigh density mapping system to rapidly map complicated circuits with sufficient spatial resolution and electrogram quality to elucidate the precise mechanism of this special ATs. Methods Of 210 consecutive patients with clinical ATs who underwent catheter ablation with the ultrahigh density mapping system,4 patients(1.9%)with CL alternans were identified. The AT alternating cycles mapped by the Rhythmia mapping system for long CL were 317±51(range 245-355)ms and for short CL were 282±51(range 235-333)ms. Both long and short cycles followed in 1∶1 sequence in all 4 patients(longshort-long-short). Results By comparing the separate maps with long and short CL,we classified ATs with CL alternans into 2 types. In type 1,CL alternans resulted from an intermittent 2∶1 conduction block through the slow conduction channel in the small circuit. In type 2,CL alternans caused by the alternated conduction velocity passing through the conduction gap were manifested. Ablation at the fractionated potentials contributes to the termination of AT in 3 of the 4 patients. Conclusions Ultrahigh density mapping system can accurately identify the mechanism of complex ATs with alternating CL. The CL alternans may be related to the intermittent conduction block within the channel of the small circuitor different conduction velocity through the identical channel. Fractionated electrogram recorded in the common isthmus or some"conduction gaps"may be a reasonable approach to terminate these ATs.展开更多
文摘Background The study was to access the feasibility and effectiveness of permanent left bundle branch pacing(LBBP)in patients with bradycardia after cardiac surgery,in comparison with conventional right ventricular outflow tract septal pacing(RVOSP).Methods A total of 50 patients with cardiac surgery who underwent permanent pacemaker implantation(PPI)were enrolled,21 patients underwent LBBP(LBBP group)and 29 patients underwent RVOSP(RVOSP group).Pacing electrical parameters,QRS duration(QRSd),echocardiographic measurements,lead and device related complications were obtained at procedure and during follow-ups.Results There were no statistically significant differences between the LBBP group and the RVOSP group at procedure and at the twelfth month’s follow-up in pacing thresholds(0.64±0.16 V vs.0.63±0.22 V)and(0.91±0.28 V vs.0.85±0.20 V),R-wave amplitude(16.68±4.52 mV vs.15.09±4.53 mV)and(14.41±8.65 mV vs.12.65±6.17 mV),pacing impedances(719.24±152.65Ωvs.639.13±177.04Ω)and(534.01±96.92Ωvs.499.18±77.87Ω).But the average ventricular pacing percentage(VP%)at the first month’s follow-up(81.96±32.06%vs.58.37±42.96%)and at the twelfth month’s follow-up(84.65±35.84%vs.53.57±38.47%)showed significant difference between two groups(P<0.05);The LBBP group produced narrower QRSd(121.13±23.91 ms)than the RVOSP group(158.00±9.69 ms)(P=0.011).There were no significant differences between the LBBP group and the RVOSP group at pre-procedure and at the twelfth month’s follow-up in echocardiographic parameters,which included left ventricular end-diastolic dimension(LVEDD)(48.76±7.08 mm vs.47.34±6.91 mm)and(50.58±10.33 mm vs.45.97±7.11 mm),left ventricular ejection fraction(LVEF)(58.33±12.64%vs.61.50±8.40%)and(55.85±16.35%vs.61.50±10.52%),and area of tricuspid regurgitation(TR)(2.79±3.65 cm2 vs.2.85±2.26 cm2)and(3.09±2.34 cm2 vs.2.95±1.92 cm2).No lead and device related complication was observed during follow-ups.Conclusions LBBP is feasible and effective in patients with bradycardia after cardiac surgery.LBBP produces narrow QRSd,which may be a preferred pacing strategy for patients after cardiac surgery.[S Chin J Cardiol 2021;22(1):13-20]
文摘Background There is little information on the factors that have influenced the long-term success rate of radiofrequency ablation of ventricular arrhythmias(VAs)at different targets.The objective of this study was to investigate the characteristics of the ablation of VAs and the factors influencing the long-term success rate in our center.Methods Totally,2751 consecutive patients(mean ages 44±15 years,male/female 58.6%/41.4%)with VAs underwent radiofrequency ablation in Guangdong Provincial People’s Hospital from 2013 to 2018 were analyzed.Baseline data were retrieved from the medical record system.Long-term follow-up data were obtained by telephone interview.We mainly recorded the patient’s last post-ablation holter,and the symptoms after ablation.Multivariable regressions were applied to assess the relationship between the long-term success rate and the influence factors.Results Through the baseline data of 2751 patients,we found that the acute success rate of ablation was 95.1%.The average follow-up time was 16±5 months(ranging from 1 to 80).In all,304 patients(11%)lost follow-up,while 2447 patients(89%)were successfully followed.The long-term success rate of ablation was 82.56%.By means of multivariable regression analyses,it was discovered that cardiovascular diseases,such as coronary heart disease(OR:0.568,95%CI:0.327-0.987),hypertension(OR:1.554,95%CI:1.100-2.198),were independently associated with the long-term success rate,as well as ablation approaches(OR:0.212,95%CI:0.082-0.550).Lower ablation success rates of the patients whose VAs were originated from some uncommon region,like left ventricular papillary muscle,Summit,etc.were observed.Conclusions Ablation approaches,concomitant cardiovascular diseases,and ablation targets were related to the long-term clinical outcome of VAs ablation.
基金supported by National Nature Science Foundation of China(No.81370295)Science and Technology Program of Guangdong(No.201508020261/No.2017A020215054)Science and Technology Planning of Guangzhou(No.2014B070705005)
文摘Backgrounds Whether the contact force(CF)-sensing catheter could improve the efficiency of pace mapping(PM)in right ventricle outflow tract(RVOT)has not been fully studied.The present study was the first investigation of the CF distribution in the right ventricle(RV)by using a CF-sensing catheter and the relationship between CF and capture threshold in RVOT.Methods In total,4543 mapping points with CF were recorded in 15 patients.Operators were blinded to CF data and data were analyzed according to 10 predefined RV segments.PM were performed at 6 different RVOT segments with 3 different intentional CF levels and 3 different pacing setup.The pacing threshold in RVOT and pacing capture level were recorded.The morphology matching score were recorded and analyzed.Results Median CF during RV mapping was 8(5-12)g and coefficient of variation was 71.64%.Median CF ranged from 9.5(5.8-16)g at the posterior-outflow tract freewall(OTFW)to 7(4-10)g at the apex.Distribution of CF≥20 g in RV predefined segments mainly located in the OTFW.Distribution of CF≤2 g in RV predefined segments mainly located in the inflow tract freewall(ITFW),anterior-OTFW,and apex.A total of 810 pacing were performed at RVOT with different CF and output.Stable capture rate could be significantly improved via increasing CF level under 2 mA output(46.7%/2-5 g vs.50%/6-9 g vs.91.1%/≥10 g),and no capture rate could be significantly declined simultaneously(16.7%/2-5 g vs.8.9%/6-9 g vs.2.2%/≥10 g).Conclusions A marked variability in CF was observed among the different predefined segments.CF mapping could improve the safety and efficacy of catheter ablation of premature ventricular contraction(PVC)/ventricular tachycardia(VT)in RV.CF was an essential factor in RVOT pace mapping process,especially under low-pacing output.[S Chin J Cardiol 2021;22(1):21-29]
基金supported by the Key Research and Development Projects of Guangdong Province(No. 2019B020230004)the National Key Research and Development Projects (No. 2018YFC1312501/2018YFC1312502)the National Natural Science Foundation (No. 81870254)
文摘Background Atrial tachycardia(AT)with cycle length(CL)alternans is uncommon and conventional mapping of this AT remains challenging. We used an ultrahigh density mapping system to rapidly map complicated circuits with sufficient spatial resolution and electrogram quality to elucidate the precise mechanism of this special ATs. Methods Of 210 consecutive patients with clinical ATs who underwent catheter ablation with the ultrahigh density mapping system,4 patients(1.9%)with CL alternans were identified. The AT alternating cycles mapped by the Rhythmia mapping system for long CL were 317±51(range 245-355)ms and for short CL were 282±51(range 235-333)ms. Both long and short cycles followed in 1∶1 sequence in all 4 patients(longshort-long-short). Results By comparing the separate maps with long and short CL,we classified ATs with CL alternans into 2 types. In type 1,CL alternans resulted from an intermittent 2∶1 conduction block through the slow conduction channel in the small circuit. In type 2,CL alternans caused by the alternated conduction velocity passing through the conduction gap were manifested. Ablation at the fractionated potentials contributes to the termination of AT in 3 of the 4 patients. Conclusions Ultrahigh density mapping system can accurately identify the mechanism of complex ATs with alternating CL. The CL alternans may be related to the intermittent conduction block within the channel of the small circuitor different conduction velocity through the identical channel. Fractionated electrogram recorded in the common isthmus or some"conduction gaps"may be a reasonable approach to terminate these ATs.
