胺碘酮治疗非瓣膜病心房颤动的疗效和安全性

本文报告胺碘酮治疗非瓣膜病心房颤动 (房颤 )的疗效与安全性。1.资料与方法 :5 5例非瓣膜病房颤患者 ,男 33例 ,女 2 2例 ;年龄 44～ 78(6 0 .9± 7.5 )岁 ,房颤病程 0 .5～ 2 0 (5 .0± 4.2 )年 ,左房直径 2 .80～ 5 .10 (3.6 4± 0 .5 0 )ｍｍ。入选标准 :阵发性房颤共 47例 ,每周至少发作 2次 ,每次至少持续 1ｈ ;或每日发作数次 ,每次持续数分钟以上。持续性房颤共 8例 ,房颤至少 1个月、但不超过 1年。用药方法 :胺碘酮负荷量0 .2ｇ、3次 /ｄ、共 1周 ,0 .2ｇ、2次 /ｄ、共 1周 ,有效或显效者从第 3周开始服用维持量。用药 2周仍无效…     

持续性心房颤动经导管射频消融治疗的方法探讨(附三例报告)

探讨经导管射频消融治疗持续性心房颤动 (简称房颤 )的可行性。 3例房颤患者房颤持续时间 2个月至 1年4个月。术前口服胺碘酮 ,1例转为窦性心律伴频发房性早搏 (简称房早 ) ,1例转为房早与短阵房颤和阵发心房扑动 (简称房扑 ) ,1例转为房早与阵发房性心动过速 (简称房速 )。经导管作点状消融或点状消融加房扑线性消融 ,2例术中房早消失 ,1例房早显著减少 ,经快速心房刺激或静脉点滴异丙肾上腺素均不能诱发房颤。 1例术后有短阵房颤发作 ,服用莫雷西嗪 ,房颤未再发作。结论 :某些持续性房颤用药物后可转复成窦性心律伴频发房早、房扑或房速 ,局部单点消融或单点消融加线性消融可以达到治疗目的。     

口服胺碘酮治疗非瓣膜病阵发性心房颤动的疗效及安全性

探讨口服胺碘酮治疗非瓣膜病阵发性心房颤动(简称房颤)的疗性和安全性,选取64例非瓣膜病阵发性房颤为随访观察对象。给药方法:负荷量,第一周每天0.6g,第二周每天0.4g,维持量每天0.1~0.2g。结果:随访1.7±1.6年。有效52例(81.3%),复发7例(13.5%)。22例出现不良反应(34.4%)。多因素Logistic回归分析显示:房颤发作时间和诱因、以及是否应用血管紧张素转换酶抑制剂(ACEI)或紧张素受体拮抗剂(ARB)为影响胺碘酮治疗阵发性房颤疗效的独立预测因素,胺碘酮对于白天发作、且与劳累或生气等因素有关的阵发性房颤疗效较高(OR6.22,P=0.05),服用ACEI或ARB可能有助于阵发性房颤的治疗(OR21.65,P=0.03)。甲状腺功能异常9例(14.1%),心率减慢8例(12.5%),恶心、厌食2例,光过敏1例,皮疹1例,复视1例,嗜睡1例,咳嗽及肺部阴影各1例。结论:①胺碘酮治疗非瓣膜病阵发性房颤疗效较高、相对安全;②胺碘酮对于多于白天发作、且与劳累或生气等因素有关的阵发性房颤疗效较高;③ACEI或ARB可能有助于阵发性房颤的治疗。     

胺碘酮治疗心房颤动临床疗效的观察

目的 :探讨胺碘酮治疗心房颤动的效果。方法 :依据房颤的频度及持续时间分为阵发性房颤 （间歇发作 ） 30例、持续性房颤 2 0例及慢性房颤 14例。结果 :使用胺碘酮治疗 8个月后总有效率分别为 87% ,70 % ,6 4 % ,治疗 12个月后总有效率分别为 80 %、6 2 %及 5 4 % ;疗效与左房大小、房颤持续时间等因素有关。服用药物期间 ,除 3例出现甲低而停药 ;1例因严重腹泻发生扭转性室速 （Tdp）外 ,其余病例无严重不良反应。结论 :胺碘酮治疗房颤安全有效 ,可以作为首选药物     

胺碘酮治疗58例心房颤动患者的体会

1资料与方法本院从2003年1~12月收治老年心房颤动(房颤)住院患者58例,其中男36例,女22例,年龄68~80(65.4±6.28)岁,房颤病程6个月~15年,阵发性房颤37例,持续性房颤21例。其中冠心病28例,高血压心脏病19例,老年退行性心瓣膜病11例。阵发性房颤每月发作3~5次,发作时间最长持续30m     

三维标测与肺静脉环状标测联合应用于心房颤动导管消融术

目的　探讨左心房三维电解剖标测与肺静脉环状标测联合指导下行心房颤动 (房颤 )导管消融术治疗房颤的可行性。方法　连续 14例药物治疗无效的房颤患者 ,男 10例 ,女 4例 ,平均年龄 5 2 4± 12 8(2 8～ 74 )岁 ,平均左心房内径 4 6 7± 5 4mm。其中阵发性房颤 10例、永久性房颤 3例、持续性房颤 1例。首先在三维标测系统指导下行左心房基质改良术 ,然后在肺静脉环状标测指导下行肺静脉节段性消融术。消融终点包括以下三点 :(1)完成所有预设的左心房消融径线 ;(2 )全部肺静脉均达电隔离 ;(3)阴性诱发结果。结果　 (1) 10例 (71 4 % )阵发性房颤达到消融终点 ;(2 )手术的总操作时间和X线曝光时间分别为 2 92± 4 9min和 5 4± 9min ;(3)随访 5 2± 5 7(1～ 2 3)周 ,7例 (5 0 % )阵发性房颤患者可以无需抗心律失常药物而维持窦性心律 ,3例 (2 1 4 % )阵发性房颤发作显著减少 ,4例 (2 8 6 % )持续性 永久性房颤仍为房颤 ;(4 )术中及随访期无任何操作相关并发症。结论　左心房三维标测与肺静脉环状标测联合应用于房颤的导管消融术安全可行 ,对于左心房增大的阵发性房颤患者具有一定效果     

胺碘酮对预激综合征合并心房颤动患者射频消融时心房颤动发作的预防作用

探讨胺碘酮对预激综合征合并阵发性心房颤动 (简称房颤 )患者房室旁道电生理特性的影响及其在射频消融术中对房颤发作的预防价值。选择有阵发性房颤史的预激综合征患者 4 7例 ,在行射频消融术前 2周口服胺碘酮0 .2g,每日 2次 ;4 5例未服胺碘酮和其他抗心律失常药者作对照组。心电生理检查测定旁道前传、逆传不应期(ERP) ,记录房室折返性心动过速 (AVRT)的诱发率和房颤的发生次数、发作时间及发作时的心室率 ,所有患者均同时行射频消融治疗。结果 :胺碘酮组旁道前传、逆传ERP均较对照组显著延长 ( 3 19± 4 8vs 2 3 5± 2 6ms ;3 0 5± 5 6vs2 4 0± 2 3ms,P均 <0 .0 1)。射频消融术中旁道存在逆传者在两组间无显著差别 ( 85 .1%vs 87.2 %) ,而胺碘酮组房颤的发作次数显著降低 ( 19.1%vs 60 .0 %,P <0 .0 1) ,发作时间显著缩短 ( 8.2± 4 .3vs2 3 .6± 11.7min ,P <0 .0 1) ,房颤发作时的心室率显著减慢 ( 12 7± 2 8vs 165± 3 4次 /分 ,P <0 .0 1) ,胺碘酮组消融治疗成功率与对照组无显著性差异 ( 10 0 %vs 95 .6%,P >0 .0 5 ) ,但手术操作与X线透视时间均显著低于对照组 ( 115 .6± 4 1.2vs 15 3 .1± 5 0 .6min ;3 5 .8± 16.4vs 4 9.3± 2 0 .2min ,P均 <0 .0 1)。结论 :胺碘酮可以有效预防射频消融     

三维标测系统指引导管消融治疗心房颤动——单中心800例总结

目的评价三维标测系统(CARTO或EnSite-NavX)指引导管消融治疗心房颤动(房颤)的总体疗效和安全性。方法2004年9月至2006年12月期间入选800例房颤患者,男性482例,女性318例,平均年龄62.1±15.6(18～82)岁。其中阵发性房颤611例,持续性房颤189例,平均左心房内径38.4±9.2(30～60)mm。采用EnSite-NavX系统260例,CARTO系统540例。对于阵发性房颤采取环肺静脉前庭电隔离,对于持续性房颤采取环肺静脉前庭电隔离 心房碎裂电位消融 二尖瓣峡部消融。术后口服华法林及ⅠC类和Ⅲ类抗心律失常药物1～3个月,每月随访心电图、24小时动态心电图一次。对于术后1个月的房颤或房性心动过速(房速)复发进行再次标测和消融。结果795例完成手术。平均手术时间161±33(140～245)min,X线透视时间17±13(12～45)min。左肺静脉电隔离率为96.5%,右肺静脉电隔离率为98.6%。阵发性房颤术中发作98例,消融终止房颤90例。阵发性房颤术后2周内早期复发137例(22.5%),103例2周后不再发作,共57例接受再次消融(6例接受三次消融)。持续性房颤环肺静脉消融恢复窦性心律30例(16.1%),转变为房速/心房扑动(房扑)15例(8.1%)。心房碎裂电位消融恢复窦性心律20例(10.8%),转变为房速/房扑23例(12.4%)。持续性房颤术后早期复发78例(41.9%),14例随访中不再发作。65例再次消融(10例接受三次消融)。所有病例房颤消融术后房扑/房速104例(13.1%),68例随访中自愈,30例再次消融,23例消融成功。并发症:心脏压塞5例(0.6%,3例内科保守治疗成功,2例外科修补),肺静脉狭窄6例(0.7%),一过性脑缺血(TIA)1例,脑栓塞2例,肠系膜动脉栓塞1例。血胸1例,气胸1例。股动脉假性动脉瘤3例,股动静脉瘘1例。术后平均随访16.2±5.7(3～27)个月,阵发性房颤550例(90.3%)无房性快速性心律失常发作(9.4%再次消融,11.5%口服抗心律失常药物);持续性房颤159例(85.5%)无房性快速心律失常发作(34.9%再次消融,28.5%服用抗心律失常药物)。结论三维标测系统(CARTO或EnSite-NavX)指引导管消融治疗房颤疗效较高,安全性好。对于阵发房颤采用环肺静脉前庭电隔离术式即有良好效果;对于持续性房颤结合碎裂电位消融、二尖瓣峡部消融等方法,而且40%患者需要多次消融以提高成功率。     

硫氮(卓)酮治疗阵发性心房颤动的长期临床观察

目的 :探讨硫氮酮对阵发性心房颤动 (房颤 )的治疗效果。方法 :选择 6 2例阵发性房颤患者 ,随机分为硫氮酮组 (31例 )和对照组 (31例 ) ,随访 3年 ,观察房颤年发作次数、持续时间和转变为持续性房颤的情况。结果 :①硫氮酮明显减少房颤年发作次数、持续时间 (P <0 .0 1) ,但用药后 1～ 2年间差异无显著性意义(P >0 .0 5 ) ;②对照组房颤年发作次数、持续时间逐年增加 ,年与年之间差异有非常显著性意义 (P <0 .0 1) ;③随访期间 ,对照组有 6例而硫氮酮组无一例转变为持续性房颤 ,两组间差异有显著性意义 (P <0 .0 5 )。结论 :硫氮酮可明显减少阵发性房颤发作次数和持续时间 ,在阻止其转变为持续性房颤也有一定的作用 ,推测与硫氮酮阻止房颤电重构的发生有关     

辛伐他汀对高血压并发阵发性心房颤动的作用及机制

目的:研究辛伐他汀对高血压并发阵发性心房颤动(房颤)患者房颤再发率和持续性房颤发生率的影响以及其对血高敏C反应蛋白(hsCRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)以及肾素、血管紧张素Ⅱ(AngⅡ)的水平的影响.方法:将87例高血压并发阵发性房颤患者随机分为2组:辛伐他汀组45例,常规治疗的同时,予口服辛伐他汀20 mg/d;对照组42例,仅给予常规治疗.追踪24个月,观察2组治疗1年后阵发性房颤再发率和持续性房颤的发生率,并检测治疗前及治疗1年后hsCRP、IL-6、TNF-α、肾素、AngⅡ的表达水平.结果:辛伐他汀组房颤再次发作7例(15.6%),明显低于对照组(14例,33.4%);辛伐他汀组转为持续性房颤2例(4.5%),亦明显低于对照组(5例,11.9%);差异均有统计学意义(P<0.05).辛伐他汀组治疗后血清hsCRP、IL-6、TNF-α、肾素、AngⅡ的水平,与对照组比较均下降,差异有统计学意义(P<0.05).所有再发房颤患者的血清hsCRP、IL-6、TNF-α、肾素、AngⅡ水平均比未再发房颤患者的明显升高,差异有统计学意义(P<0.01).结论:高血压并发阵发性房颤的患者应用辛伐他汀治疗,能够降低阵发性房颤的再发率,减少持续性房颤的发生率,而且降低血清hsCRP、IL-6、TNF-α、肾素、AngⅡ的水平,后者可能与房颤再发相关,提示炎症反应及肾素-血管紧张素-醛固酮系统的激活具有促进心房颤动的发生和持续的作用.     

Effect of low-dose amiodarone on atrial fibrillation or flutter in Japanese patients with heart failure.

The efficacy and safety of amiodarone in the management of atrial fibrillation (AF) or flutter in 108 Japanese patients with heart failure was retrospectively examined. Thirty-four (41%) of the 82 patients who were in sinus rhythm after 1 month of amiodarone administration had their first recurrence, 70% of cases occurring within 1 year of initiation. The cumulative rates of maintenance of sinus rhythm were 0.68, 0.55, and 0.47 at 1, 3, and 5 years, respectively. Amiodarone was more effective in maintaining sinus rhythm in patients with paroxysmal AF or flutter than in those with the persistent form (p<0.05). The cumulative rates for cases that remained in permanent AF were 0.04, 0.11, and 0.14 at 1, 3, and 5 years, respectively. Apart from suppressing AF, the mean heart rate during Holter monitoring was significantly decreased with amiodarone therapy in cases of permanent AF. Adverse effects requiring the discontinuation of amiodarone therapy occurred in 16% of patients. Low-dose amiodarone therapy may prevent AF or flutter in Japanese patients with heart failure.     

Role of oral amiodarone in patients with atrial fibrillation and congestive heart failure

Background

Amiodarone is recognized as the most effective therapy for maintaining sinus rhythm (SR) post cardioversion in patients with atrial fibrillation (AF). It is also recommended for controlling AF in patients with congestive heart failure (CHF). We retrospectively examined the efficacy and safety of oral amiodarone in patients with AF and CHF.

Methods

Forty-eight consecutive AF patients whose left ventricular ejection fraction (LVEF) was less than 50% and B-type natriuretic peptide (BNP) was higher than 100 pg/ml were investigated retrospectively, and divided into 3 groups: paroxysmal AF, 16 patients; persistent AF, 9 patients; and permanent AF, 23 patients.

Results

The permanent AF group had a longer history of AF, larger left ventricular end-diastolic diameter (LVDd) and left atrial diameter (LAD) than paroxysmal and persistent AF groups (p < 0.05). After median follow-up of 265 days, amiodarone suppressed paroxysms in 88% of paroxysmal AF patients, while SR was maintained in all persistent AF patients, and 35% of permanent AF patients. Of the 32 persistent and permanent AF patients, 12 (71%) out of 17 maintained SR after successful electrical cardioversion, and conversion to SR occurred spontaneously in 5 (33%) out of 15. The effective group had significantly smaller LVDd and LAD than the ineffective group. In the effective group, BNP decreased significantly from 723 ± 566 pg/ml to 248 ± 252 pg/ml, (p < 0.0005) and LVEF increased significantly from 33 ± 7% to 50 ± 13% (p < 0.0005) during follow up, while no changes were observed in the ineffective group. The patients with low LVEF (≤30%) benefited comparably from amiodarone to the patients with LVEF >30%. Complications occurred in 24 (50%) patients leading to discontinuation of amiodarone in 11 (23%).

Conclusions

Oral amiodarone helped restore SR in paroxysmal and persistent AF patients with CHF. The successful rhythm control by amiodarone resulted in the improvement of LV function and the decrease of BNP levels.     

普罗帕酮或胺碘酮联合福辛普利治疗心房颤动的研究

目的评价长期口服低剂量普罗帕酮或胺碘酮联合福辛普利治疗阵发性房颤的疗效及安全性。方法2004年1月～2005年1月在本院门诊及住院就诊的患者，共入选113例阵发性房颤患者，男性60例，女性53例，年龄61．2±5．4（52～72）岁，病程35．7±24．3（3～120）月，其中46例合并高血压，8例合并冠状动脉粥样硬化性心脏病。患者随机分为两组：胺碘酮组（A组）56例，普罗帕酮组（B组）57例。A组，先给予胺碘酮200meg次，3次，d，服用1周；继之200mg／次，2次，d，服用1周；第3周时剂量调整为200meg次，1次，d，以后维持此剂量。B组，给予普罗帕酮150mg／次，3次，d。所有患者均给予福辛普利，高血压患者10mg／d，血压正常者5mg／d。所有患者均随访1年。结果共有94例患者达到随访终点，其中A组46例，B组48例；在随访中，A组用药前1-4次／月，用药后为0．6次／月，p〈0．05，差异有显著性。用药前B组需住院或急诊治疗平均为1．2次／月，用药后为0．9次／月，差异没有显著性。随访结束时，B组复发者24例，47．8％患者仍维持窦律；A组复发者11例，77．1％的患者仍维持窦律，结果明显优于B组（p〈0．01）。A组11例复发者用药前3月平均发作14．2次，用药后3月、6月、9月、12月分别平均发作3．0次、2．6次、2．5次、2．4次，较用药前发作次数均有下降（p值均小于0．05），在随访中没有一例发展为持续性房颤。B组24例复发者用药前3月平均发作18．0次，用药后3月、6月、9月、12月分别平均发作9．5次、10．8次、12．1次、13．5次，较用药前发作次数均有下降（p值均小于0．05），但随着用药时间延长，发作次数呈上升趋势；而且在随访的一年内有3例发展为持续性心房颤动。结论长期低剂量口服普罗帕酮或胺碘酮联合福辛普利均能有效减少阵发性房颤发作的频率，?     

Acupuncture for paroxysmal and persistent atrial fibrillation: An effective non-pharmacological tool?

In Traditional Chinese Medicine,stimulation of the Neiguan spot has been utilized to treat palpitations and symptoms related to different cardiovascular diseases.We evaluated whether acupuncture might exert an antiarrhythmic effect on patients with paroxysmal or persistent atrial fibrillation(AF).Two sets of data are reviewed.The first included patients with persistent AF who underwent electrical cardioversion to restore sinus rhythm.The second included patients with symptomatic paroxysmal AF.All subjects had normal ventricular function.Acupuncture treatment consisted of 10 acupuncture sessions on a once a week basis with puncturing of the Neiguan,Shenmen and Xinshu spots.In patients with persistent AF,the recurrence rate after acupuncture treatment was similar to that observed in patients on amiodarone,but significantly smaller than that measured after sham acupuncture treatment or in the absence of any antiarrhythmic drugs.In a small group of patients with paroxysmal AF,acupuncture resulted in a significant reduction in the number and duration of symptomatic AF episodes.In conclusion,we observed that acupuncture of the Neiguan spot was associated with an antiarrhythmic effect,which was evident in patients with both persistent and paroxysmal AF.These preliminary data,observed in 2 small groups of AF patients,need to be validated in a larger population but strongly suggest that acupuncture may be an effective non-invasive and safe antiarrhythmic tool in the management of these patients.     

Efficacy of amiodarone for preventing the recurrence of symptomatic paroxysmal and persistent atrial fibrillation after cardioversion.

BACKGROUND: It has been previously reported that the efficacy of class I antiarrhythmics in preventing the recurrence of symptomatic paroxysmal and persistent atrial fibrillation (AF) is limited when AF lasts for 48 h or more. However, it is unclear whether the efficacy of amiodarone, a class III drug, is superior to class I antiarrhythmics in patients with long-lasting AF. METHOD AND RESULTS: The relationship between the duration of tachycardia and the efficacy of amiodarone in preventing recurrence of tachycardia was examined in 55 patients (37 men, 18 women, mean age 68+/-9 years) to whom amiodarone was administered after electrical or pharmacological cardioversion for paroxysmal and persistent AF. In 26 patients, paroxysmal and persistent AF ceased within 48 h after onset (Group A), and in the other 29 patients, it ceased after 48 h (Group B). Patient characteristics and actuarial recurrence-free rates were compared between the 2 groups. The mean follow-up period was 30+/-11 months. No statistically significant difference between the groups was found in patient characteristics. Actuarial recurrence-free rates in Group A and B at 1, 3, 6, 9, and 12 months were 100%, 81%, 69%, 62%, and 54%, and 93%, 79%, 66%, 52%, and 48%, respectively (p=NS at 12 months). The period of maintenance of sinus rhythm was 14.7+/-3.2 months in group A and 13.3+/-3.3 months in group B (mean+/-SE, p=NS). CONCLUSION: In the case of amiodarone, efficacy for maintaining sinus rhythm after cardioversion of AF was not biased by the duration of arrhythmia. This observation suggests amiodarone is effective in maintaining normal sinus rhythm after cardioversion, even in patients with long-lasting AF and electrical atrial remodeling.     

Non-invasive assessment of fibrillatory activity in patients with paroxysmal and persistent atrial fibrillation using the Holter ECG

OBJECTIVE: Automatic analysis of the frequency content of the fibrillatory baseline on the surface ECG accurately reflects the average rate of atrial fibrillation (AF). This frequency measurement correlates with the behavior of AF and predicts the response to administration of ibutilide, a new antiarrhythmic drug. Neither the temporal pattern of fibrillatory frequency in spontaneous paroxysmal or persistent AF, nor its response to chronic antiarrhythmic medication has been studied so far. METHODS AND RESULTS: Holter ECG recordings were made in 20 patients during AF. One minute ECG segments were selected for analysis. The frequency content of the fibrillatory baseline was then quantified using digital signal processing. After high-pass filtering, the QRST complexes were subtracted using a template matching algorithm. The resulting fibrillatory baseline signal was subjected to Fourier transformation, displayed as a frequency power spectrum and the peak frequency (f) was determined. In 11 patients (7 male, 4 female, age 62 +/- 10 years) 31 paroxysmal AF episodes were analyzed. Duration ranged from 1 min to 665 min (115 +/- 175 min). Initial mean peak f measured 5.1 +/- 0.7 Hz (range 3.9 to 6.9 Hz). There was a positive correlation between f and AF duration (R = 0.53, p = 0.002). AF of less than 15 min duration (n = 13) showed a lower f (4.8 +/- 0.6 Hz) when compared with longer lasting episodes (n = 18, 5.3 +/- 0.7 Hz, p = 0.03). In short AF episodes f was constant, whereas in longer-lasting episodes f increased to 5.8 +/- 0.5 Hz (p < 0.001) within 5 min. In 9 patients (9 male, age 58 +/- 8 years) with persistent AF oral antiarrhythmic drugs (amiodarone n = 5, sotalol n = 3, flecainide n = 1) were given prior to electrical cardioversion for prophylaxis of AF recurrence. Frequency measurements were obtained at baseline and 3 to 5 days after initiation of drug administration. At baseline mean f measured 6.9 +/- 0.4 Hz. Frequency was reduced by antiarrhythmic drugs to 5.8 +/- 0.4 Hz (p < 0.001). CONCLUSIONS: (1) The duration of paroxysmal AF episodes can be predicted using spectral analysis of ECG recordings of AF episodes. (2) An increase in fibrillatory frequency is associated with AF persistence. (3) This technique can be used to monitor the response to antiarrhythmic medication.     

Clinical efficacy of flecainide acetate in atrial fibrillation

Seventy-seven patients with symptomatic atrial fibrillation (AF) received oral flecainide acetate (247 +/- 8 mg/day). In 66 patients, previous antiarrhythmic trials consisted of 1-9 drugs. In 55 cases, AF was paroxysmal. It was persistent in 22 patients. Conversion and/or no recurrence of AF was achieved in 40 patients (52%) by flecainide alone and in 11 (14%) by the combination of flecainide and amiodarone. The mean flecainide serum level was 535 +/- 46 ng/ml. Age, presence of coronary artery disease or electrocardiographic parameters were not useful for predicting clinical response. In persistent AF, flecainide efficacy decreased with the duration of arrhythmia. Side effects concerned conduction (26%) and congestive heart failure (5%).     

The acute treatment of supraventricular tachycardia with endovenous amiodarone

In the present study we evaluated 35 patients of both sexes, aged 21-84, with newly occurring supraventricular tachyarrhythmias, 19 atrial fibrillation (AF), 6 atrial flutter (FL) and 10 paroxysmal supraventricular tachycardias (PSVT). They were treated with a single amiodarone infusion up to two hours after the restoration of a stable sinus rhythm or to a maximus dose of 2,400 mg (in 24 hours). Plasma amiodarone concentration and QTc were measured at the restoration of sinus rhythm and twelve hours after the amiodarone withdrawal. Amiodarone infusion restored a stable sinus rhythm in all 10 patients of the PSVT group (100%), in 5 of the FL group (83%) and in 16 of the AF group (84%). The average dose needed to stop PSVT was lesser than for AF and FL (M + SE: 473.3 +/- 36.88 vs 1842.1 + 259.6 vs 1548.8 +/- 345.5 mg; p less than 0.001). The average plasma amiodarone concentration at the restoration of sinus rhythm was 2450.4 +/- 175.9 SE ng/ml in all the tachyarrhythmias as a whole without any statistically significant difference among PSVT, FL and AF. Moreover no correlation exists between plasma amiodarone concentrations and the amount of amiodarone infused. QTc showed a statistically significant transient lengthening at the restoration of sinus rhythm, but not twelve hours after amiodarone withdrawal. In conclusion, a single dose of amiodarone is effective and safe in all newly occurring supraventricular tachyarrhythmias, without any important side effect and with a high therapeutic index in pharmacologic cardioversion as alternative treatment to cardioversion.     

Characterization of paroxysmal and persistent atrial fibrillation in the human left atrium during initiation and sustained episodes

INTRODUCTION: Atrial fibrillation (AF) in the left atrium (LA) is poorly defined in terms of regional differences in the degree of organization, characteristics of paroxysmal and persistent variants, and electrophysiologic events that develop at the onset of episodes. METHODS AND RESULTS: The study population consisted of 21 patients (15 men and 6 women; mean age 58+/-9.4 years) with paroxysmal (10 patients) or persistent (11 patients) AF. Mapping of the LA during sustained episodes and the onset of AF was performed with a 64-electrode basket catheter. At the onset of AF, repetitive beats starting with atrial premature complexes and ending with generation of the earliest fibrillatory activity were defined as intermediary rhythm. Patients with paroxysmal AF had longer AF cycle lengths and more pronounced regional differences than patients with persistent AF. In total, AF cycle lengths in the LA in patients with persistent AF were 20% shorter than in patients with paroxysmal AF. Initiation of AF was preceded by an intermediary rhythm of 5.5+/-2.5 cycles (6.3+/-2.7 cycles in paroxysmal AF vs 4.2+/-1.0 cycles in persistent AF; P = 0.026). At the onset of AF, the earliest generators of fibrillatory activity were located more frequently in the posterior wall of the LA. CONCLUSION: AF in the LA displays substantial regional differences in terms of AF cycle lengths and degree of organization. Patients with persistent AF have shorter cycle lengths and a higher degree of disorganized activity than patients with paroxysmal AF. Intermediary rhythms play an important role in initiation of AF via activation of generator regions in the LA.