经食管超声心动图分析左心耳内部形态结构对左心耳封堵术的指导价值

目的:探讨经食管超声心动图（TEE）分析左心耳内部形态结构对左心耳封堵术的指导价值。方法:选取行左心耳封堵术患者110例,术前均给予TEE检查,分析左心耳开口最大径、梳状肌至开口距离等参数。结果:110例患者左心耳封堵术均成功,出现残余分流19例,无残余分流91例;手术时间17~80 min,平均手术时间（45.49±13.30） min;辐射量560~2 100 mGy,平均辐射量（980.50±112.40） mGy;曝光时间520~1 950 s,平均曝光时间（890.50±120.40） s;ACP封堵器尺寸18~33 mm,平均（25.50±2.50） mm;TEE所测左心耳开口最大径为（23.12±2.24）mm,小于ACP封堵器尺寸（P<0.05）;TEE所测左心耳开口最大径与ACP封堵器尺寸呈正相关（r=0.426, P<0.05）;手术时间<45 min和≥45 min患者左心耳开口最大径、左心耳深度及开口与深度比值比差异无统计学意义（P>0.05）;手术时间<45 min患者梳状肌到开口距离为（16.60±3.22） mm,明显大于手术时间≥45 min患者（P<0.05）;梳状肌到开口距离与手术时间呈负相关（r=-0.524, P<0.05）。结论:TEE分析左心耳内部形态结构对左心耳封堵术有一定指导价值,值得临床使用。     

经皮穿刺封堵左心耳的应用解剖

目的:了解正常人左心耳解剖学特征,为经皮穿刺封堵左心耳提供相关的应用解剖.方法:解剖测量30例(男21,女9)正常成年人的心脏标本.结果:左心耳开口的长径、短径及长、短径的最大伸展径分别为(18.5±6.3)、(10.9±5.0)、(24.8±6.3)和(17.6±6.1)mm.左心耳开口周长为(51.7±15.3)mm.左心耳腔的深度为(20.5±6.4)mm;腔的长径、短径及其最大伸展径分别为(15.8±5.7)、(10.4±4.9)、(19.7±5.9)和(14.4±5.8)mm.左心耳与左上、左下肺静脉口的距离及与二尖瓣环的最短距离分别为(4.8±1.9)、(7.8±2.7)和(10.3±3.4)mm.结论:根据本文测量结果,经皮穿刺封堵左心耳是可行的,封堵器心房面的大小应根据左心耳开口的大小及与周边结构的距离来选择.     

Impact of sex differences on outcomes in patients with non-valvular atrial fibrillation undergoing left atrial appendage closure: A single-center experience

Female patients affected by non-valvular atrial fibrillation (NVAF) have a higher risk of stroke compared with male patients. Left atrial appendage (LAA) closure has been demonstrated as a reasonable alternative to warfarin therapy for stroke prevention in patients with NVAF. However, the impact of sex-related differences on outcomes in patients undergoing LAA closure (LAAC) remains unclear. Our study investigated the differences in LAAC efficacy and safety endpoints between sexes. 387 consecutive patients undergoing WATCHMAN device implantation were enrolled and stratified by sex. Baseline clinical characteristics, procedural data, severe peri-procedural complications and long-term outcomes were compared between men and women. Measurements of LAA width and depth, device implantation success rate, and the frequency of severe peri-procedural complications were comparable between the two groups. After an average follow-up length of two years post LAAC, no significant differences were observed in the risks for composite thromboembolic events (P = 0.096), major bleeding (P = 0.129), and combined primary (co-primary) efficacy events (P = 0.231) between sexes, but the risk of all-cause death decreased significantly in women compared with men (P = 0.045). After performing propensity matching adjustment for residual confounders, the sex-related differences in the cumulative ratio of freedom from all-cause death did not reach statistical significance (P = 0.062), as was also observed with the cumulative ratio of freedom from composite thromboembolic events (P = 0.104), major bleeding (P = 0.134), and co-primary efficacy events (P = 0.241). The observed annual rate of thromboembolic events was significantly decreased by 67.1% (P < 0.01) and 52.5% (P < 0.05) and the observed annual rate of bleeding was reduced by 33.6% (P < 0.05) and 43.5% (P < 0.05) in men and women when compared with the predicted risk based on CHA₂DS₂VASc score and HAS-BLED score, respectively. LAAC can be considered as an effective and safe strategy in preventing thromboembolic events and decreasing bleeding risks in NVAF patients, regardless of sex. LAAC appears to normalize the sex-specific differences in NVAF patients both in terms of safety and efficacy.     

左心耳封堵器体外疲劳耐久性试验方法

目的心房颤动是临床上常见的心律失常之一,左心耳封堵术是在传统药物治疗之外发展的通过微创介入封堵左心耳以达到预防血栓栓塞目的的新技术。左心耳封堵器在体内承受周期循环载荷可能会导致封堵器的固定盘发生疲劳断裂,威胁患者生命,并且血流对阻流膜的冲击造成阻流膜破裂导致封堵效果不佳。因此需要建立一种疲劳耐久性试验方法去评估封堵器在人体中的耐疲劳性能。方法首先根据医药行业标准YY 0808—2010确定疲劳试验采用直径控制法;然后确定在疲劳试验中左心耳封堵器的规格、振幅;最后进行疲劳试验获得封堵器在1900万次疲劳(内皮化时间点)和3.8亿次疲劳(10年疲劳时间点)后的状态。结果1900万次疲劳后,阻流膜无破损、缝合线无松脱掉落、金属部位无断裂,封堵器未移动;3.8亿次疲劳后,左心耳封堵器金属部位无断裂、无磨损。结论本研究可为研发和生产左心耳封堵器的企业及科研机构提供一种便捷、高效的疲劳耐久性评价方法。     

心房颤动患者心房Ⅰ型胶原重构与左心房扩大

目的：探讨心房颤动患者心房Ⅰ型胶原重构与左心房扩大在房颤发病机制中可能的作用以及它们之间的关系。方法:取24例心脏病患者的右心耳组织(房颤12 例,为房颤组；窦性心律12 例，为窦律组)。（1）HE染色，观察房颤组与窦律组心肌纤维以及细胞核、细胞外基质的差异。（2）免疫组化染色，在普通显微镜下观察窦律组与房颤组心房Ⅰ型胶原并使用图像分析系统分析2组的胶原含量分数（collagen volume fraction, CVF），统计2组间Ⅰ型胶原含量分数（CVF-Ⅰ）的差异。（3）〖JP+1〗对CVF-I与左房直径进行Pearson相关分析。结果:(1)房颤组CVF-Ⅰ高于窦律组(CVF-I: 9.29 ±0.85 vs 6.90±1.47, P<0.01)；（2）房颤组心房大于窦律组（6.16±1.01 vs 4.47±0.99， P<0.01）；（3）心房大小与Ⅰ型胶原含量不存在相关性（r=0.33, P>0.05）。 结论:房颤患者的心房纤维化程度增加、左心房扩大，纤维化与左房扩大可能通过一定的途径，直接或间接参与了房颤的发病过程。     

Morphology of the left atrial appendage

Background: When examining the left atrial appendage by transesophageal echocardiography, differences in size and shape of the left atrial appendage are to be observed. The study was carried out with the aim of investigating the morphology of the left atrial appendage and to find associations with pathologic cardiac findings. Methods and results: In 220 cases (106 female, 114 male, mean age 72 ± 13 years) a cast of the left atrial appendage was made after the post mortem examination by using synthetic resin. In 198 cases an ECG was available (sinus rhythm n = 143, atrial fibrillation n = 55). The casts were described in respect to course and ramifications of the principal axis. The casts were measured concerning orifice diameters, outline, and volume. Most frequently (42%) the course of the principal axis was angulated below 100°. More than five ramifications of the principal axis were found in 56% of the casts. The volume ranged from 770–19,270 mm³ (mean 5,220 ± 3,041). When comparing the clinical and autopsy-data of the patients with the morphology of the casts, associations could be found between the volume of the casts and atrial fibrillation (7,060 mm³ as compared to 4,645 mm³ in sinus rhythm, P < 0.01), left ventricular hypertrophy (5,740 mm³ as compared to 4,639 mm³ without hypertrophy, P < 0.01), myocardial scars (5,923 mm³ as compared to 4,891 mm³ without scars, P < 0.05), closed foramen ovale (5,515 mm³ as compared to 4,037 mm³ with patent foramen ovale, P < 0.01), and left atrial appendage thrombi (8,566 mm³ as compared to 5,027 mm³ without thrombi, P < 0.01). Conclusion: Left atrial appendages are formations greatly varying in volume and shape. This variability should be considered when interpreting images of the left atrial appendage, and in particular when diagnosing thrombi. © 1995 Wiley-Liss, Inc.     

Regional left atrial interstitial remodeling in patients with chronic atrial fibrillation undergoing mitral-valve surgery

Ablation of the left atrial free wall around the pulmonary vein ostia (LAFW) may be effective in the treatment of chronic atrial fibrillation associated with mitral disease (CAF-MVD). Using light and conventional electron microscopy analyses, we wanted to evaluate, in CAF-MVD, the interstitial remodeling in the LAFW as well as in a more remote region, such as the left atrial appendage (LAA). LAFW and LAA samples were obtained from 33 CAF-MVD patients during combined mitral surgery and radiofrequency ablation and from 16 autoptic controls. Interstitial fibrosis (IF) and perivascular fibrosis (PF), capillary densities and the maximal oxygen diffusion distance were morphometrically determined. In CAF-MVD patients, the LAFW, compared with the LAA, showed a higher percentage of IF (7.16±3.23% versus 2.51±1.40%, respectively), a lower myocardial capillary density per mm² (830±106 versus 989±173) and an increased oxygen maximal diffusion distance (19.70±1.27 m versus 18.13±1.58 m). All these values were also significantly different than controls. No differences were found in evaluating PF. At variance with the LAA, in CAF-MVD patients, the LAFW around the pulmonary vein ostia is a region characterized by a marked interstitial remodeling such that it may be morphologically indicated as an appropriate target for ablation treatment aimed at sinus rhythm restoration.     

右心房梗死伴左心房高频起搏诱发慢性房颤的电生理特性研究

目的： 建立右心房梗死伴左心房高频起搏新型慢性心房颤动(AF)模型并探讨其电生理特性。方法： 24只健康新西兰大白兔随机分为3组：对照组(C)、起搏组(P)、心房梗死+起搏组(I)。C组：在左心房外膜缝合固定一起搏电极,但不起搏;P组：在左心房外膜缝合固定一起搏电极并以1 000 beats/min的频率高频起搏;I组：结扎右冠状动脉心房分支,并在左心房外膜缝合固定一起搏电极,以1 000 beats/min的频率高频起搏。采用心外膜程序起搏技术测定心房肌的电生理特性。结果： (1) I组:起搏3周后AF诱发成功率高达100%。(2) I组、P组在起搏1 h、1周、3周后心房有效不应期（ERPA）均缩短;I组、P组、C组：起搏3周后在基本起搏周期（PCL）200 ms时的ERPA分别为(87.5±12.8) ms、(81.3±12.5) ms、(115.0±7.6) ms,I组、P组与C组比较,显著差异（P<0.01）。(3)在频率适应性方面,I组、P组均表现为频率适应不良,在术后3周时表现明显,与C组比较差异显著(分别P<0.01,P<0.05)。 (4) I组在起搏3周后P波时限延长与P组、C组比较差异显著(P<0.05,P<0.01)。（5）I组：快速起搏后1 h至3周,均表现为ERPA缩短、心房相对不应期(RRPA)延长与C组比较显著差异（P<0.01）、房间传导时间（IACD）延长与P组、C组比较显著差异（均P<0.01）。结论：右心房梗死+左心房高频起搏建立兔慢性AF与传统的单纯心房起搏相比,AF诱发成功率高并且稳定,其电生理参数有特征性意义,表现为ERPA缩短,频率适应不良,RRPA延长,IACD延长。     

Use of new liquid nitrogen cryocatheter in the surgical treatment of atrial fibrillation: clinical experience, mid- and long-term results

Surgical treatment of atrial fibrillation (AF) evolves to less invasive, safer and technically easier procedures mostly due to the electrophysiological studies, technological progress and creativeness in ablation systems construction. We present first clinical experience, mid- and long-term results of AF treatment with new liquid nitrogen cryothermy device for endocardial application. In 26 patients we have proved the feasibility and clinical effectiveness of liquid nitrogen cryocatheter ablation reaching more than 70% of sinus rhythm rate in long follow-up from 3 up to 24 months.     

慢性房颤病人的AFW研究

利用房颤波谱分析系统（ASpectraAnalysisSystemforAtrialFibrillationWaves，简称AFW）对慢性持续心房颤动患者进行研究，其目的是评价该系统的临床实用价值。     

不同类型心房纤颤患者急性缺血性脑卒中的临床特点分析

目的心房纤颤(AF)是急性缺血性脑卒中(AIS)的一种重要危险因素。不同类型的AF危险因素及发病机制皆存在差异。比较阵发性心房纤颤(Pa AF)与持续性心房纤颤(Pe AF)患者AIS的临床特点,以明确两者发病机制存在的差别。方法242例AIS患者,其中男性103例,女性139例;年龄53~86岁,平均年龄为78.4岁。根据AF特点分为Pa AF组(57例)与Pe AF组(185例),分别比较两组患者的基本信息、危险因素、临床特点和影像学特点。结果与Pa AF组相比,Pe AF组患者年龄较大,女性患者所占比例偏高。Pe AF组入院时美国国立卫生院神经功能缺损(NIHSS)评分与出院时改良Rankin量表(m RS)评分皆高于Pa AF组。大脑中动脉(MCA)狭窄在Pa AF患者更普遍,而Pe AF组更多伴随左心房增大。结论与Pa AF相比,Pe AF患者AIS短期预后差。这可能与不同亚型AIS在两组中的不同发病率有关,也与两组患者左心房产生的血栓结构及体积存在差异相关。     

Assessment of atrial electromechanical interval using echocardiography after catheter ablation in patients with persistent atrial fibrillation

We sought to investigate variation of atrial electromechanical interval after catheter ablation procedure in patients with persistent atrial fibrillation using pulse Doppler (PW) and pulse tissue Doppler imaging (PW-TDI). A total of 25 consecutive in-patients with persistent atrial fibrillation, who restored sinus rhythm after ablation procedure, were recruited in our cardiac center. Echocardiography was performed on each patient at 2 hours, 1 day, 5 days, 1 month and 3 months after the ablation therapy, and atrial electromechanical delay was measured simultaneously by PW and PW-TDI. There was no significant difference between PW and TDI in measuring atrial electromechanical delay. However, at postoperative 2 hours, peak A detection rates were mathematically but nonsignificantly greater by PWTDI than by PW. Second, there was a significant decreasing trend in atrial electromechanical interval from postoperative 2 hours to 3 months, but only postoperative 2-hour atrial electromechanical interval was significantly greater than atrial electromechanical interval at other time. Lastly, patients without postoperative 2-hour atrial electromechanical interval had a significantly longer duration of atrial fibrillation as compared to those with postoperative 2-hour atrial electromechanical interval, by the PW or by PW-TDI, respectively. In patients with persistent atrial fibrillation, atrial electromechanical interval may decrease significantly within the first 24 hours after ablation but remain consistent later, and was significantly related to patients' duration of atrial fibrillation. Atrial electromechanical interval, as a potential predicted factor, is recommended to be measured by either PW or TDI after 24 hours, when patients had recovered sinus rhythm by radiofrequency ablation.     

Anatomical features and clinical importance of left atrial diverticula

To assess the anatomical features and clinical importance of left atrial diverticula and atrial accessory appendages in patients undergoing cardiac computed tomography with multidetector computed tomography. A total of 1305 consecutive patients (385 female, 29.5%; 920 male, 70.5%) were assessed using electrocardiogram‐gated computed tomography between May 2010 and June 2013. The anatomical features and the prevalences of left atrial diverticula and left atrial accessory appendages were retrospectively assessed by four radiologists. The relationships between the prevalence and size of the diverticula and the age and gender of the patients were assessed. Among the 1305 patients, 610 (46.7%) exhibited 708 left atrial diverticula, and 62 (4.8%) exhibited left atrial accessory appendages. The most common locations of the left atrial diverticula were the right anterior superior wall (n = 328, 46.3%) and the lateral superior wall (n = 96, 13.5%). In addition to classical cystic and tubular diverticula, 49 (3.7%) of the patients exhibited mixed (cystic‐tubular), conical, or hook‐shaped diverticula and diverticular forms containing mural calcifications. There was no significant relationship between the prevalence of diverticula and the age and gender of the patients (P > 0.05). In addition to tubular and cystic diverticula, the left atrial wall can host different diverticular forms (such as mixed, conical, calcific, and hook shaped). It could be beneficial to assess the left atrium using MDCT to determine the source of emboli in cryptogenic embolism and to reduce complications associated with interventional procedures performed for left atrial arrhythmias. Clin. Anat. 27:738–747, 2014. © 2013 Wiley Periodicals, Inc.     

Myocyte changes and their left atrial distribution in patients with chronic atrial fibrillation related to mitral valve disease

It has been found that the pulmonary veins and adjacent left atrial posterior wall (LAPW) are deeply involved in both the initiation and maintenance of atrial fibrillation (AF), and the identification of these high-risk sites has aroused great interest in investigating their histopathologic substrate. We used light and conventional electron microscopy to evaluate the differential myocyte and interstitial changes in LAPW and left atrial appendage (LAA) samples from 28 patients with chronic AF undergoing mitral valve surgery and from 12 autoptic controls. There were always more myocytes with loss of sarcomeres in the LAPW than in the LAA (19.9% +/- 7.7% versus 8.2% +/- 5.0%; P < .0001), and the LAPW showed more marked immunohistochemical evidence of dedifferentiation, characterized by the reexpression of smooth muscle actin. In pathological left atria, myocyte diameter in the LAPW and LAA was comparable (19.0 +/- 1.5 versus 18.5 +/- 2.0 microm; not significant) but larger than in the controls (11.9 +/- 0.8 and 12.1 +/- 1.3 microm, respectively; P < .0001). A terminal deoxynucleotidyltransferase assay did not reveal any myocyte apoptosis. The LAPW also showed more interstitial fibrosis than the LAA (7.49% +/- 3.34% versus 2.80% +/- 1.35%; P < .0001). Ultrastructural examination confirmed the presence of myocyte myocytolysis in the perinuclear area and showed changes in mitochondrial shape. In conclusion, the LAPW in patients with chronic AF related to mitral valve disease seems to be a particular anatomical site in which major myocyte and interstitial changes are concentrated, whereas the LAA is more protected. This remodeling may increase the heterogeneity of LAPW electrical conduction, thus confirming this location as an elective target for the ablation treatment of AF.     

心房颤动中间质纤维化的分子生物学研究

心房颤动是临床上最常见的一种心律失常,临床及实验均发现心房颤动中心房存在明显纤维化。心房纤维化被认为是发生心房颤动的结构基础,改变了心房的结构进而使心房功能受损。心房颤动心房纤维化的发生机制尚未完全明确。目前对心房颤动心房纤维化结构改变的研究发现：一系列细胞因子特别是肾素-血管紧张素系统、转化生长因子-β1、基质金属蛋白酶等在心房颤动及纤维化的发生、维持中作用明显。该文探讨了心房颤动心房纤维化的分子生物学发生机制及研究进展。     

The effects of a bidirectional cavo-tricuspid isthmus block in persistent atrial fibrillation

Purpose

Hybrid therapy with catheter ablation of the cavo-tricuspid isthmus (CTI) and continuation of anti-arrhythmic drugs (AAD), or electrical cardioversion with AADs might be alternative treatments for patients with persistent atrial fibrillation (AF). The goal of study was to assess the long term success rate of hybrid therapy for persistent AF compared to antiarrhythmic medication therapy after electrical cardioversion and identify the independent risk factors associated with recurrence after hybrid therapy.

Materials and Methods

A total of 32 patients with persistent AF who developed atrial flutter after the administration of a class Ic or III anti-arrhythmic drug were enrolled. This group was compared with a group (33 patients) who underwent cardioversion and received direct current cardioversion with AADs. Baseline data were collected, and electrocardiogram and symptom driven Holter monitoring were performed every 2-4 months.

Results

There was no significant difference in the baseline characteristics between the groups. The 12 month atrial arrhythmia free survival was better in the hybrid group, 49.0% vs. 33.1%, p=0.048. However, during a mean 55.7+/-43.0 months of follow up, the improved survival rate regressed (p=0.25). A larger left atrium size was an independent risk factor for the recurrence of AF after adjusting for confounding factors.

Conclusion

Despite favorable outcome during 12 month, the CTI block with AADs showed outcomes similar to AAD therapy after electrical cardioversion over a 12 month follow up period. Minimal substrate modification with AADs might be an alternative treatment for persistent AF with minimal atrial remodeling.     

微小RNA与心房颤动心房纤维化

心房纤维化是心房颤动(房颤)发生与维持的重要因素,微小RNA(microRNA,miRNA)通过调控纤维化相关靶基因,在房颤心房纤维化中起着重要作用。因此,深入研究miRNA在心房纤维化中的作用机制将为房颤的诊治提供新的思路。     

Cerebrovascular accidents differ between patients with atrial flutter and patients with atrial fibrillation

IntroductionFew studies have explored the potential impact of atrial flutter (AFl) on ischaemic stroke (IS) outcome. The aim of the present study was to compare the clinical course of IS in patients with AFl and patients with atrial fibrillation (AF).Material and methodsA retrospective analysis of patients consecutively admitted to a tertiary care centre between 2013 and 2015 due to IS or transient ischaemic attack with permanent AFl or permanent or persistent AF was performed.ResultsThe study groups consisted of 528 patients, including 490 (92.8%) patients with AF and 38 (7.2%) patients with AFl. The mean age and prestroke CHA2DS2-VASc scores were similar between the patients with AFl and those with AF. Most IS cases in the AF group were classified as cardioembolic strokes (74.9% vs. 39.5% in AFl, p < 0.01), and lacunar strokes were the most common in the AFl group (47.4% vs. 14.3% in AF, p < 0.01). The multivariable analysis revealed that the presence of AF (OR = 8.6, 95% CI: 1.2–57, p = 0.02), lacunar stroke (OR = 0.1, 95% CI: 0.03–0.31, p < 0.001), baseline Rankin scale score (OR = 16.6, 95% CI: 9.8–28), lack of prestroke therapeutic anticoagulation (OR = 6.1, 95% CI: 1.1–33), diabetes (OR = 2.9, 95% CI: 1.3–6.5, p < 0.01), chronic heart failure (OR = 14.2, 95% CI: 5.8–34, p < 0.001), and current smoking (OR = 0.92, 95% CI: 0.39–0.99, p < 0.01) were significantly associated with the stroke outcome.ConclusionsDisabling or fatal IS was observed less often in patients with AFl than in patients with AF. This finding can possibly be explained by the more frequent occurrence of lacunar strokes in the AFl group compared with that in the AF group.     

芳香烃受体在心房颤动患者心房组织中的表达及意义

目的:检测芳香烃受体(AhR)在风湿性心脏病(风心病)心房颤动患者右心耳组织中的表达,探讨其在心房纤维化中的作用及意义。方法:取风心病换瓣手术患者的右心耳组织为实验组,其中风心病窦性心律组25例和风心病慢性房颤组11例;取先天性心脏病(先心病)心脏手术患者的右心耳组织12例作为对照组。采用Masson染色法检测右心耳组织胶原含量,采用免疫组化技术检测AhR、AhR核转位蛋白(ARNT)和CYP1A1蛋白的表达和分布,采用实时荧光定量PCR检测AhR、ARNT和CYP1A1的mRNA表达,采用Western blot检测AhR、ARNT和CYP1A1的蛋白表达。结果:与先心病组相比,风心病窦律组和风心病慢性房颤组胶原含量和AhR、ARNT、CYP1A1的表达明显增高;与风心病窦律组相比,风心病慢性房颤组胶原含量和AhR、ARNT、CYP1A1的表达明显增高(P0.05)。结论:风心病患者心房组织中AhR的表达与纤维化程度相关;AhR/ARNT/CYP1A1在风心病患者中表达增加,可能参与风心病心房纤维化的发生发展。     

高频刺激左心房引起家兔慢性心房颤动

目的： 探讨以高频率起搏刺激左心房建立家兔慢性心房颤动模型的方法。 方法： 20只家兔随机分为实验组及对照组，对照组为假手术组，植入起搏器但不起搏，实验组10只家兔予开胸植入高频率起搏器(1 000 次/分)刺激左心房30 d，术后定期监测起搏、心房颤动的发生情况、房颤时心室率变化，同时测定起搏前及房颤发生后心房有效不应期（AERP）的变化。 结果： 实验组均完成了实验，术后第7 d，7只（70％）兔发生了房颤，2周时共有8只（80％）发生了房颤并能稳定维持（与对照组比较，P＜0.01），30 d时仍示房颤，其余2只兔至30 d时仍呈起搏心律，对照组则未发生任何心律失常情况。心房颤动时的心室率最初明显增快（P＜0.05），随后有所降低（P＜0.05），但仍高于基础心室率（P＜0.05）。AERP缩短，AERP频率适应不良，与基础状态相比有显著意义。 结论： 长期高频率起搏刺激家兔左心房是建立慢性房颤模型的有效方法。