Significance of permanent atrial fibrillation in idiopathic dilated cardiomyopathy

The significance of atrial fibrillation (AF) in idiopathic dilated cardiomyopathy (IDCM) remains discussed. The purpose of the study was to evaluate the clinical significance of permanent atrial fibrillation in patients with IDCM.

Methods

Systematic noninvasive and invasive studies including Holter monitoring, measurement of left ventricular ejection fraction (LVEF), electrophysiological study and coronary angiography were performed in 323 patients with IDCM; all patients had a left ventricular ejection fraction (LVEF) < 40%. The studies were indicated for spontaneous ventricular tachycardia (VT) in 69 patients, syncope in 103 patients and nonsustained VT on Holter monitoring in 151 asymptomatic patients. Sixty-five patients were in permanent AF (group I). Remaining patients were in sinus rhythm at the time of evaluation (group II). Programmed ventricular stimulation using up to 3 extrastimuli in control state and if necessary after isoproterenol was systematic. Patients were followed 3 ± 2 years.

Results

Mean age was significantly older in group I (61±8 years) than in group II (52 ± 12) (P < 0.01). Syncope (31 vs 36%), spontaneous sustained VT (18 vs 23%); mean LVEF (28 ± 9% vs 29 ± 9%), VT induction (25 vs 35%) were similar in both groups. During the follow-up, there were no statistical differences between groups I and II concerning each event: sudden death occurred in 13 patients, 1.5% of group I patients and 5% of group II patients (NS); a death related to heart failure occurred 22 patients, 5% of group I patients and 7% of group II patients (NS); heart transplantation was performed in 13 patients, 8% of group I patients and 3% of group II patients (NS).

Conclusions

An older age is the only significant clinical factor associated with the presence of a permanent atrial fibrillation in idiopathic dilated cardiomyopathy. The presence of permanent AF does not increase the induction of a sustained ventricular tachycardia and does not affect the general prognosis of IDCM.     

Reversible dilated cardiomyopathy associated with glucagonoma

An association between dilated cardiomyopathy and glucagonoma has not previously been described. A case of a 54 year old woman with tachycardia and congestive heart failure is described. Initial evaluation included an echocardiogram, which showed dilated cardiomyopathy with an ejection fraction of 15%. Coronary angiography and endomyocardial biopsy did not identify a secondary cause of her cardiomyopathy. She subsequently developed necrolytic migratory erythema, and imaging of her pancreas identified a pancreatic mass with a major increase of her serum glucagon concentration. Tachycardia persisted despite treatment with beta blockers. After resection of her tumour, her heart rate normalised and subsequently her heart returned to normal size and function. Glucagon is used to treat overdoses of beta blockers and calcium channel blockers, increasing heart rate by increasing myocardial cyclic AMP concentrations. Although rare, in the appropriate clinical setting, glucagonoma should be considered in the differential diagnosis for tachycardia and dilated cardiomyopathy.     

Reversible dilated cardiomyopathy related to hyperthyroidism

Heart failure is one of the most known complications of hyperthyroidism, more commonly high-output heart failure, but some patients may develop dilated cardiomyopathy with low ejection fraction. We report a 35-year-old man, with hyperthyroidism, atrial fibrillation, and severe heart failure with 43% of ejection fraction. After the definitive treatment of the hyperthyroidism with radioiodine, heart failure was reverted, with symptomatic improvement and echocardiographic normalization including a normal ejection fraction (69%). There are several cases of reversion of heart failure due to hyperthyroidism treatment, but most of them with a high-output heart failure. Mechanisms by which hyperthyroidism can lead to heart failure and its treatment are discussed. We conclude that treatment of hyperthyroidism may reverse this thyroid related heart failure, even in severe cases with systolic dysfunction.     

Reversible dilated cardiomyopathy induced by methamphetamine

This brief report details the case of a woman who was thought, after extensive evaluation, to have idiopathic congestive cardiomyopathy. It was subsequently found that systolic ventricular dysfunction was due to amphetamine abuse, and that ventricular function normalized after discontinuation of this drug.     

Reversible dilated cardiomyopathy induced by ventricular asynchrony

The authors present the case of a patient who developed left bundle branch block with asynchrony of left ventricular contraction and, secondarily, a dilated hypokinetic cardiomyopathy. There were no signs of an ischaemic, toxic or inflammatory cause for the cardiomyopathy whereas cardiac resynchronisation by biventricular stimulation rapidly restored a normal left ventricular ejection fraction. This suggests that asynchrony of left ventricular contraction is not necessarily the consequence of a dilated hypokinetic cardiomyopathy but it may also be considered as a possible cause.     

扩张型心肌病合并心房颤动的临床特征及危险因素分析

目的 探讨扩张型心肌病（dilated cardiomyopathy,DCM）合并心房颤动（atrial fibrillation,AF）患者的临床特征和危险因素。方法 回顾性分析2015年1月至2018年5月间于我院住院的DCM患者79例（DCM组）及DCM合并AF患者35例（DCM-AF）为研究对象,收集患者临床资料及相关检查结果,比较其临床特征,并采用多因素Logistic回归分析研究DCM患者发生AF的危险因素。结果 单因素结果分析显示,DCM-AF组与DCM组在年龄［（61.14±6.91）岁比（53.94±6.06）岁］、NYHA分级［（3.14±0.69）比（2.44±0.51）］、病程［4.5（2.0,7.0）年比1.5（1.0,2.0）年］、肺动脉高压［23（65.71%）比33（41.77%）］、氨基末端脑钠肽前体（N terminal pro brain natriuretic peptide,NT-proBNP）［3297.50（599.25,8219.75）pg/ml比2015.50（617.50,2812.50）pg/ml］、尿酸［（492.86±107.59）μmol/L比（414.19±79.31）μmol/L］、总胆固醇［（3.92±0.95）mmol/L比（3.61±0.79）mmol/L］、甘油三酯［（1.54±0.89）mmol/L比（1.19±0.63）mmol/L］、左心房内径（left atrial diameter,LAD）［（49.53±5.94）mm比（44.67±4.72）］、左心室收缩末期内径（left ventricular end systolic diameter,LVESD）［（51.73±4.89）mm比（56.07±6.76）mm］、左室射血分数（left ventricular ejection fraction,LVEF）［（35.29±7.46）%比（32.06±6.73）%］的差异均有统计学意义（P<0.05）。多因素Logistic回归分析发现,年龄、NYHA分级、病程、尿酸、左心房内径是DCM患者发生AF的影响因素（P均<0.05）。结论 年龄大、NYHA分级差、病程长、尿酸高、左心房内径大是DCM患者发生AF的独立危险因素。     

RF ablation of longstanding persistent atrial fibrillation in patient with familial dilated cardiomyopathy

A vicious circle of interactions between dilated cardiomyopathy and longstanding persistent AF/AFL may cause symptoms of advanced congestive heart failure. In a 31-year-old patient with diagnosis of familial dilated cardiomyopathy and permanent AF lasting for five years, gradually decreased left ventricular ejection fraction (LVEF) and increased diameter of heart chambers - left ventricular diastolic dimension (LVdD) 7.7 cm, left atrium (LA) 5.4 cm, and LVEF 15% were noted. Pharmacological treatment was ineffective Successful RF ablation of AF/AFL substrate (CTI block, PVs isolation, CFAE ablation, roof and MIG line, CS applications) reversed symptoms of significant heart remodeling (LVdD 5.9 cm, LA 4.3 cm, LVEF 50%).     

Left ventricular dysfunction due to atrial fibrillation in patients initially believed to have idiopathic dilated cardiomyopathy.

Ten patients aged 22 to 80 years (median 57) with severe left ventricular (LV) dysfunction and atrial fibrillation (AF) with rapid ventricular response were evaluated after therapy. Because most patients were unaware of their arrhythmia, duration was usually unknown. All patients had heart failure symptoms; 9 presented with New York Heart Association class III or IV disability, and 1 with class II disability. Initial LV ejection fraction ranged from 12 to 30% (median 25). No patient had symptomatic coronary artery disease (4 underwent angiography). Myocarditis and infiltrative processes were excluded by biopsy in 5 patients. All patients were considered initially to have idiopathic dilated cardiomyopathy with secondary AF. Ventricular rate was controlled in all patients, with sinus rhythm restored in 5. At follow-up (median 30 months, range 3 to 56), all patients were asymptomatic. LV ejection fraction after treatment ranged from 40 to 64% (median 52). It is concluded that in some patients initially considered to have idiopathic dilated cardiomyopathy, AF with rapid ventricular response may be the primary cause rather than the consequence of severe LV dysfunction. LV dysfunction may be completely reversible with ventricular rate control.     

瑞舒伐他汀对扩张型心肌病心脏再同步化治疗后阵发性房颤的影响

目的 观察瑞舒伐他汀对扩张型心肌病（dilated cardiomyopathy,DCM）患者心脏再同步化治疗（cardiac resynchronization therapy,CRT）后阵发性心房颤动（paroxysmal atrial fibrillation,PAF）的影响并探讨其机制。方法 入选我院DCM行CRT后患者44例,随机分为瑞舒伐他汀治疗组（试药组）和常规治疗组（对照组）各22例,所有患者试验前及18个月后检测低密度脂蛋白胆固醇(LDL-C)、脑钠尿肽(BNP)、超敏C反应蛋白(hs-CRP)水平并行超声心动图检查,跟踪分析起搏器中记录到的心房颤动事件。结果 两组患者在基线状态差异均无统计学意义。18个月后,共42人完成随访,与基线数据相比较,试验组hs-CRP、BNP、左房内径(LAD)、左室舒张末内径(LVEDD)均显著降低（P<0.05,P<0.01）,对照组仅BNP、LVEDD显著降低（P<0.05）,两组左室射血分数(LVEF)均显著升高（P<0.05),两组LDL-C均有所降低,但差异无统计学意义,试药组PAF发生率显著低于对照组〔10%(2/21) vs. 38%(8/21),P<0.05〕。结论 瑞舒伐他汀可显著降低DCM患者CRT后PAF的发生率,其作用机制可能通过减轻炎症反应而非依赖降脂作用。     

Effect of cardioversion of atrial fibrillation on left ventricular function in dilated cardiomyopathy. A multicenter study

A group of 73 patients with idiopathic dilated cardiomyopathy were followed up for an average of 22 +/- 7 months to assess the medium term evolution of echocardiographic parameters of left ventricular function and, in particular, the consequences of cardioversion of atrial fibrillation. Seventy nine per cent of patients presented with cardiac failure. Left bundle branch block was observed in 20% and ventricular arrhythmias were frequent in 31%, complex in 62% with episodes of non-sustained ventricular tachycardia in 10% of cases. Left ventricular dilatation was greater in patients with complete left bundle branch block (p less than 0.003). Atrial fibrillation was present in 14 patients (19%) who were generally older than the rest of the study population (p less than 0.02) and was associated with less severe left ventricular dysfunction (p less than 0.01). Return to sinus rhythm was obtained in 9 patients. Echocardiographic data was obtained in 64 patients after an average of 6.2 +/- 1.7 months. Left ventricular function improved during the follow-up period and returned to normal in 12% of cases. Reduction of atrial fibrillation to sinus rhythm was the only predictive factor of normalisation of left ventricular function (p less than 0.02). The changes in left ventricular end diastolic dimension and fractional shortening was less marked in the group of 56 patients in sinus rhythm or chronic atrial fibrillation (normalisation of left ventricular function in 8% of cases) than in the group of 8 patients in which atrial fibrillation was converted to sinus rhythm (normalisation of left ventricular function in 50% of cases).(ABSTRACT TRUNCATED AT 250 WORDS)     

扩张性心肌病患者心房Cx43蛋白的表达及其意义

目的:观察扩张性心肌病（dilated cardiomyopathy,DCM）患者心房连接蛋白43（Cx43）的表达、磷酸化的Cx43（pCx43）及其分布特征。探讨Cx43与房颤（atrial fibrillation,AF）之间的关系。方法: 18例接受心脏移植术的DCM患者中,8例无AF史且手术时为窦性心律（SR,SR组）,6例有AF史但手术时为SR（AF+SR组）,4例有AF史且手术时有AF（AF+AF组）。用超声心动图(ECG)测定左心房大小与左心室收缩功能;用免疫印迹法及免疫荧光染色法检测Cx43、pCx43及其分布。结果: DCM患者的左心房直径(LAD)、左室射血分数(LVEF)在SR、AF+SR、AF+AF组间均没有显著差异。与SR组相比,AF+SR组心房组织中Cx43和pCx43无显著差异;AF+AF组总Cx43的表达量及pCx43显著升高(P<0.01及P<0.05)。病理观察提示,AF+AF组Cx43和pCx43升高,Cx43向细胞两侧分布,且pCx43升高。结论: DCM患者的房颤节律伴随Cx43的表达、磷酸化及其分布异常。     

Left atrial deformation and nonischemic dilated cardiomyopathy

Background

Left ventricular filling pressure (LVFP) is raised by the compromised contraction and impaired ventricular compliance in dilated hearts with systolic dysfunction. Timely recognition and staging of this condition are important for planning of the treatment strategy and making the prognosis. Two-dimensional speckle- tracking echocardiography (2D-STE) has recently enabled the quantification of left atrial (LA) myocardial deformation dynamics. In this study, echocardiographic indicators of increased LVFP and NT-pro-BNP were compared with LA strain measured by 2D-STE.

Methods

A total of 49 nonischemic dilated cardiomyopathy (DCMP) patients were included in the study. All patients underwent standard 2D echocardiography. In the 2D-STE analysis of the LA, global longitudinal LA strain during ventricular systole (GLAs-res) and strain during late diastole (GLAs-pump) were obtained. NT-pro-BNP levels were measured. The patients were divided into two groups—normal (group 1) and increased (group 2) LVFP—according to E/A ratio, E velocity, and E/E’ ratio.

Results

LAVi-max, LAVi-min, and NT-pro-BNP were higher in group 2, whereas LAtotalEF, LAactiveEF, GLAs-res, and GLAs-pump were lower. In univariate analysis, a good negative correlation was seen between GLAs-res vs. NT-pro-BNP, GLAs-res vs. LAVi-max, and GLAs-res vs. E/E’ ratio; a good negative correlation was present between GLAs-pump vs. NT-pro-BNP, GLAs-pump vs. LAVi-max, and GLAs-pump vs. E/E’ ratio. LAVi-max, LAactiveEF, NT-pro-BNP, GLas-res, and GLAs-pump were studied by logistic regression analysis. GLAs-res (p?=?0.009, OR?=?0.593, 95?% CI 0.4–0.877), NT-pro-BNP (p?=?0.028, OR?=?1.027, 95?% CI 1.003–1.052), and LAactiveEF (p?=?0.022, OR?=?0.001, 95?% CI 0.001–0.024) were found to be independent predictors of increased LVFP.

Conclusion

2D-STE-based LA function is impaired in patients with nonischemic DCMP. LA reservoir and pump function parameters together with NT-pro-BNP levels might be useful in estimating LVFP in this patient group.     

Heart rate variability in dilated cardiomyopathy

Chronic heart failure is associated with excessive neurohormonal activation. Analysis of heart rate variability is considered a valid technique for assessment of the autonomic balance of the heart. Twenty symptomatic patients of dilated cardiomyopathy in NYHA class II-IV symptomatic status and as many normal controls were subjected to 24 hours Holter monitoring to assess the heart rate variability with both time domain and frequency domain analysis. Age of the patients ranged from 12 to 67 years (mean +/- SD 38.6 +/- 7 years), the male-female ratio was 4:1. The left ventricular ejection fraction of the patients was between 18-42 percent (mean +/- SD 30.2 +/- 9%) and all received diuretics, digoxin and angiotensin-converting enzyme inhibitors. Heart rate variability parameters measured included mean heart rate with standard deviation, hourly heart rate with SD and the mean of all normal RR intervals from the 24-hour recording. Time domain measures calculated were SD of all normal RR intervals, SD of 5 minute mean RR intervals and root mean square of difference of successive RR intervals. Using spectral plots, frequency domain subsets of low frequency and high frequency were analysed and expressed in normalised units. Total power was also measured. In the dilated cardiomyopathy patients, mean 24-hour heart rate in beats per minute was significantly higher in comparison to controls (82 +/- 13 vs 72 +/- 8; p < 0.001) whereas mean hourly heart rate with standard deviation (msec) was significantly lower (97 +/- 41 vs 232 +/- 25; p < 0.001), SD of all normal RR intervals (msec) was 85.5 +/- 26.3 vs 139.4 +/- 16.9 in controls (p < 0.001), SD of 5 minute mean RR intervals (msec) was also significantly less in patients in comparison to controls (75.8 +/- 39.6 vs 130.8 +/- 20.3; p < 0.001). However, although root mean square of difference of successive RR intervals (msec) was reduced in patients (30.1 +/- 9.3 vs 37.3 +/- 11.7; p < 0.05), the difference was non-significant. Low frequency power (0.05-0.15 Hz) (normalised units) was reduced in the dilated cardiomyopathy group (0.0721 +/- 0.003 vs 0.136 +/- 0.047 in the control group; p < 0.001). High frequency power (0.35-0.50 Hz) (normalised units) (0.08 +/- 0.05 in patients vs 0.09 +/- 0.02 in controls; p > 0.1) and total power frequency (0.02-0.50 Hz) (normalised units) (0.34 +/- 0.05 in patients vs 0.35 +/- 0.12 in controls; p > 0.1) was non-significantly different in the two groups. Regression analysis showed a significant decrease in SD of all normal RR intervals, SD of 5 minute mean RR intervals, low frequency, high frequency, total power and a non-significant decrease in root mean square of difference of successive RR intervals with a decrease in ejection fraction percent whereas there was a significant decrease in SD of all normal RR intervals, SD of 5 minute mean RR intervals, low frequency and total power and a less significant decrease in root mean square of difference of successive RR intervals and high frequency power with an increase in NYHA class. At 6 months duration, 6 patients were lost to follow-up, 3 patients were readmitted (2 for congestive cardiac failure, one of paroxysmal supraventricular tachycardia). One patient who was NYHA class IV at baseline was readmitted for congestive cardiac failure and showed much lower heart rate variability parameters compared to the average of the patients. We conclude that in symptomatic dilated cardiomyopathy patients, heart rate variability parameters are significantly reduced in comparison to control subjects.     

Increase in radionuclide left ventricular ejection fraction after cardioversion of chronic atrial fibrillation in idiopathic dilated cardiomyopathy.

To assess the potential improvement in left ventricular ejection fraction after cardioversion of chronic atrial fibrillation to sinus rhythm in idiopathic dilated cardiomyopathy, we studied prospectively 17 patients, aged 58 +/- 6 years, by radionuclide angiocardiography at rest. Left ventricular ejection fraction was determined before treatment and at a mean delay of 4.7 months after cardioversion. Return to sinus rhythm was obtained in 12 patients, pharmacologically or by electrical cardioversion. Five patients remained in atrial fibrillation. No clinical, echocardiographic or haemodynamic finding could predict the success of cardioversion. In chronic atrial fibrillation, the ejection fraction did not change significantly: 30.0 +/- 9.1% (19 to 44%) at the first evaluation and 29.5 +/- 8.3% (22 to 41%) after 4.7 months. After successful cardioversion, left ventricular ejection fraction improved from 32.1 +/- 5.3% (24 to 41%) to 52.9 +/- 9.7% (37 to 71%) (P less than 0.001). The difference was 20.8 +/- 11.3% and left ventricular ejection fraction was normalized in 50% (6/12) of the patients. There was a significant reduction in the cardiothoracic ratio on chest X-rays and of the left ventricular end-diastolic diameter on echocardiography; fractional shortening increased (27.7 +/- 4.3% vs 20.3 +/- 2.7%, P less than 0.01). A third evaluation was realized after a mean delay of 11.7 months in the patients with successful cardioversion. Sinus rhythm was present in 83% (10/12) of the patients: seven patients were reevaluated by radionuclide angiography. The improvement in left ventricular function observed at the 4.7 months evaluation was still present. In two patients with recurrence of atrial fibrillation, there was a severe deterioration of left ventricular systolic function.(ABSTRACT TRUNCATED AT 250 WORDS)     

扩张型心肌病合并心房静止与传导阻滞一家系

目的分析一家系扩张型心肌病(DCM)合并心房静止与传导阻滞患者的临床与心电表现,探讨其可能的发病机制。方法对一DCM合并心房静止与传导阻滞家系进行调查,并分析体表心电图及食管和心腔内电图。结果该家系3例患病(先证者,以及其姐和其兄),其母50岁猝死。2例表现为全心房静止,1例为部分心房静止,并合并左前分支和不完全性右束支阻滞,超声心动图示心房无收缩、房室扩大。2例因心房不能起搏,改为置入VVI起搏器,1例直接行VVI起搏。结论该家系符合遗传性DCM合并传导系统疾病的诊断。     

应变率成像技术评价扩张型心肌病患者左房功能的研究

目的应用应变率成像（SRI）技术评价扩张型心肌病患者左房功能,探讨应变率成像技术在临床评价左房功能的应用价值。方法对19例扩张型心肌病患者（DCM组）和22例健康者（对照组）,采用SRI技术测量左房各壁收缩期、舒张早期、舒张晚期应变率峰值（SSR、ESR、ASR）,求各组平均值并比较分析。结果DCM组左房壁ESR、ASR、SSR均较健康对照组减低,差异均有统计学意义（P〈0．05）。结论SRI可定量评估扩张型心肌病患者左房功能的改变。     

Autoantibodies against M2-muscarinic acetylcholine receptors: new upstream targets in atrial fibrillation in patients with dilated cardiomyopathy.

AIM: To characterise the clinical significance of M2-muscarinic acetylcholine receptor autoantibodies (M2-AAB) in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: Sera from 104 patients with DCM, age-matched with 104 patients with idiopathic atrial fibrillation (Af) and 104 healthy control subjects, were screened for M2-AAB by enzyme-linked immunosorbent assay (ELISA). IgG purified by Protein-A column was also used as a primary antibody in ELISA. In DCM, M2-AAB were detected in 40% of patients using whole sera and in 36% of patients using purified IgG. M2-AAB were also found in several patients with idiopathic Af (23%, 23%), and these frequencies were significantly higher than those in healthy subjects (8%, 8%). Af was more common in AAB-positive than in AAB-negative patients with DCM. Multivariable analysis confirmed that M2-AAB were independent predictors of the presence of Af in such patients. We determined electrophysiological changes by adding patient purified M2-AAB to chick embryos. Purified IgG from both Af and DCM patients exhibited negative chronotropic effects and induced supraventricular arrhythmias. CONCLUSION: M2-AAB may play a role in mediating the development of Af in patients with DCM.