Arrhythmogenic right ventricular cardiomyopathy characterized by recurrent syncope during exercise: A case report

BACKGROUNDArrhythmogenic right ventricular (RV) cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty tissue. It may be asymptomatic or symptomatic (palpitations or syncope) and may induce sudden cardiac death, especially during exercise. To prevent adverse events such as sudden cardiac death and heart failure, early diagnosis and treatment of arrhythmogenic RV cardiomyopathy (ARVC) are crucial. We report a patient with ARVC characterized by recurrent syncope during exercise who was successfully treated with combined endocardial and epicardial catheter ablation.CASE SUMMARYA 43-year-old man was referred for an episode of syncope during exercise. Previously, the patient experienced two episodes of syncope without a firm etiological diagnosis. An electrocardiogram obtained at admission indicated ventricular tachycardia originating from the inferior wall of the right ventricle. The ventricular tachycardia was terminated with intravenous propafenone. A repeat electrocardiogram showed a regular sinus rhythm with negative T waves and a delayed S-wave upstroke from leads V1 to V4. Cardiac magnetic resonance imaging showed RV free wall thinning, regional RV akinesia, RV dilatation and fibrofatty infiltration (RV ejection fraction of 38%). An electrophysiological study showed multiple inducible ventricular tachycardia as of a focal mechanism from the right ventricle. Endocardial and epicardial voltage mapping demonstrated scar tissue in the anterior wall, free wall and posterior wall of the right ventricle. Late potentials were also recorded. The patient was diagnosed with ARVC and treated with combined endocardial and epicardial catheter ablation with a very satisfactory follow-up result.CONCLUSIONClinicians should be aware of ARVC, and further workup, including imaging with multiple modalities, should be pursued. The combination of epicardial and endocardial catheter ablation can lead to a good outcome.     

A case of arrhythmogenic right ventricular cardiomyopathy in a 70-year-old patient

A 70-year-old man was admitted because of syncope and dyspnea. Two months before admission, exertional dyspnea occurred with syncope. Ventricular tachycardia with a monomorphic left bundle-branch block configuration was detected. An echocardiographic examination showed severe dilatation and diffuse, severe hypokinesis of the right ventricle, with thrombus formation in the right ventricular apex. Based on the clinical picture, the patient was diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC). This case emphasizes the need for early identification of RV abnormalities in patients with ARVC to determine appropriate therapy.     

Arrhythmogenic right ventricular cardiomyopathy/dysplasia: a review and update

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a predominantly genetically determined and heritable form of cardiomyopathy that is characterized pathologically by the replacement of myocytes by adipose and fibrous tissue and leads to right ventricular failure, arrhythmias, and sudden cardiac death. The estimated prevalence of ARVC/D in the general population ranges from 1 in 2,000 to 1 in 5,000, men are more frequently affected than women, with an approximate ratio of 3:1. ARVC/D can be inherited as an autosomal dominant disease with reduced penetrance and variable expression, autosomal recessive inheritance is also described. There have been 12 genes identified which are linked to ARVC/D, encoding several components of the cardiac desmosome. Dysfunctional desmosomes resulting in defective cell adhesion proteins, such as plakoglobin (JUP), desmoplakin (DSP), plakophilin-2 (PKP-2), and desmoglein-2 (DSG-2) consequently cause loss of electrical coupling between cardiac myocytes, leading to myocyte cell death, fibrofatty replacement and arrhythmias. Diagnosis is based on the finding a combination of characteristic abnormalities in family history, electrocardiography, cardiac imaging as well as endomyocardial biopsy (original task force criteria). Therapeutic options remain limited because of the progressive nature of ARVC/D. Competitive athletics should be avoided. Patients with ARVC/D with a history of having been resuscitated from sudden cardiac death, patients with syncope, very young patients, and those who have marked right ventricular involvement are at the highest risk for arrhythmic death and also, the presence of left ventricular involvement is a risk factor. Several authors concluded that patients who meet the Task Force criteria for ARVC/D are at high risk for sudden cardiac death and should undergo ICD placement for primary and secondary prevention, regardless of electrophysiologic testing results. The role of electrophysiologic study and VT catheter ablation in ARVC/D remains poorly defined, and is frequently used as a palliative measure for patients with refractory VT. The progressive nature of ARVC/D suggests that catheter ablation would not be a long-term curative procedure. Sotalol proved to be highly effective in patients with ARVC/D and inducible as well as non-inducible ventricular tachycardia; if it is ineffective in inducible ventricular tachycardia response to other antiarrhythmic drugs is unlikely and therefore non-pharmacological therapy without further drug testing should be considered. Orthotopic heart transplantation is considered in patients with progressive heart failure and intractable recurrent ventricular arrhythmias     

Arrhythmogenic right ventricular cardiomyopathy with left ventricular involvement and aortic dissection

Ten years ago, a 59-year-old patient presented with ventricular fibrillations. The resting ECG showed findings typical for ARVC. Echocardiography and ventriculography confirmed the diagnosis of ARVC showing a dilated right ventricle with aneurysms. MRI showed additional fatty replacement of the LV. Furthermore, the diagnosis of a chronic aortic dissection was established. Two years after ICD implantation, the patient died of progressive right heart failure. On autopsy, most of the RV and parts of the LV were replaced by fatty tissue, and the media of the aorta showed degenerative changes. A pathogenetic link between the two diseases remains speculative at this time.     

Characterization of familial and sporadic arrhythmogenic right ventricular cardiomyopathy in Finland

Background: Autosomal dominant inheritance is reported in arrhythmogenic right ventricular cardiomyopathy (ARVC) but the prevalence of the familial and sporadic forms in the general population is unknown.

Aim: To evaluate the familial occurrence and clinical features of ARVC in the genetically homogenous Finnish population.

Methods: The study included 29 Finnish ARVC index patients and 135 relatives from 21 families evaluated. They underwent echocardiography, 24‐hour electrocardiographic monitoring, signal‐averaged electrocardiography, and exercise stress test.

Results: Twenty‐two index patients had ventricular arrhythmias as first manifestation, and three developed arrhythmias later. The right ventricle (RV) was mildly affected in 22 and strongly dilated in 7 index patients. Patients with dilated RV manifested first symptoms at younger age (mean 28 years) than those without RV dilatation (mean 38 years). Of the 135 relatives, ARVC was present in 12 (9%) patients belonging to 5 of the 21 families studied, resulting in 24% familial involvement. In addition, 46 relatives (34%) had subtle cardiac abnormalities, suggesting subclinical presentation.

Conclusions: The ARVC in Finland presents with distinct arrhythmic and RV dilative subtypes. The sporadic disease is similar to the familial one which may reflect low penetration in relatives. The proportion of familial manifestation of ARVC in Finland seems comparable to that elsewhere in Europe.     

Right ventricular volume analysis by angiography in right ventricular cardiomyopathy

Imaging of the right ventricle (RV) for the diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is commonly performed by echocardiography or magnetic resonance imaging (MRI). Angiography is an alternative modality, particularly when MRI cannot be performed. We hypothesized that RV volume and ejection fraction computed by angiography would correlate with these quantities as computed by MRI. RV volumes and ejection fraction were computed for subjects enrolled in the North American ARVC/D Registry, with both RV angiography and MRI studies. Angiography was performed in the 30° right anterior oblique (RAO) and 60° left anterior oblique (LAO) views. Angiographic volumes were computed by RAO view and two-view (RAO and LAO) formulae. 17 subjects were analyzed (11 men and 6 women), with 15 subjects classified as affected, and two as unaffected by modified Task Force criteria. The correlation coefficient of MRI to the two-view angiographic analysis was 0.72 (P = 0.003) for end-diastolic volume and 0.68 (P = 0.005) for ejection fraction. Angiographically derived volumes were larger than MRI derived volume (P = 0.009) and with the slope in a linear relationship equal to 0.8 for end diastolic volume, and 0.9 for RV ejection fraction (P < 0.001), computed by the two view formula. End-diastolic volumes and ejection fractions of the RV obtained by dual view angiography correlate with these quantities by MRI. RV end-diastolic volumes are larger by RV angiography in comparison with MRI.     

Arrhythmogenic right ventricular cardiomyopathy mimics: role of cardiovascular magnetic resonance

Background

Cardiovascular magnetic resonance (CMR) is commonly used in patients with suspected arrhythmogenic right ventricular cardiomyopathy (ARVC) based on ECG, echocardiogram and Holter. However, various diseases may present with clinical characteristics resembling ARVC causing diagnostic dilemmas. The aim of this study was to explore the role of CMR in the differential diagnosis of patients with suspected ARVC.

Methods

657 CMR referrals suspicious for ARVC in a single tertiary referral centre were analysed. Standardized CMR imaging protocols for ARVC were performed. Potential ARVC mimics were grouped into: 1) displacement of the heart, 2) right ventricular overload, and 3) non ARVC-like cardiac scarring. For each, a judgment of clinical impact was made.

Results

Twenty patients (3.0%) fulfilled imaging ARVC criteria. Thirty (4.6%) had a potential ARVC mimic, of which 25 (3.8%) were considered clinically important: cardiac displacement (n=17), RV overload (n=7) and non-ARVC like myocardial scarring (n=4). One patient had two mimics; one patient had dual pathology with important mimic and ARVC. RV overload and scarring conditions were always thought clinically important whilst the importance of cardiac displacement depended on the degree of displacement from severe (partial absence of pericardium) to epiphenomenon (minor kyphoscoliosis).

Conclusions

Some patients referred for CMR with suspected ARVC fulfil ARVC imaging criteria (3%) but more have otherwise unrecognised diseases (4.6%) mimicking potentially ARVC. Clinical assessment should reflect this, emphasising the assessment and/or exclusion of potential mimics in parallel with the detection of ARVC major and minor criteria.     

Late enhancement: a new feature in MRI of arrhythmogenic right ventricular cardiomyopathy?

Aim of the study was to evaluate whether late enhancement (LE) in contrast-enhanced MRI can be used to characterize fibrofatty myocardial replacement in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC). Fifteen patients with suspected ARVC underwent CE-MRI using a 1.5 T scanner. Long and short axis SSFP cine images and T1-weighted fast spin echo images were collected in all patients. After injection of 0.2 mmol/kg Gd-DTPA (Magnevist, Schering, Berlin, Germany), inversion recovery gradient echo images were acquired in long and contiguous short axes to detect myocardial LE indicating areas of fibrous tissue within the myocardium. For definition of ARVC, the ESC Task force criteria were used. In 7 (47%) of 15 patients, ARVC was diagnosed based on the ESC criteria. In all of these 7 patients, MRI showed morphologic or functional criteria of ARVC according to the ESC. LE of the right ventricular myocardium was detected in 5 (71%) of the 7 ARVC patients, additional LE of the left ventricular myocardium in 2 of these patients. None of the 7 patients meeting the ARVC diagnostic criteria had fatty RV infiltration demonstrable by conventional T1-weighted imaging. Eight patients neither showed morphologic criteria of ARVC nor LE. In conclusion, late enhancement can be detected in the right and left ventricular myocardium in some ARVC patients. LE might represent intramyocardial areas of fibrous tissue.     

Arrhythmogenic right ventricular cardiomyopathy: a cause of sudden death in young people

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an increasingly recognized cause of ventricular tachycardia and sudden cardiac death in young people, notably young athletes. The best treatment is not clear, although options include antiarrhythmic drugs, radiofrequency ablation, and implantable defibrillators.     

Heart rate variability in arrhythmogenic right ventricular cardiomyopathy correlation with clinical and prognostic features

The identification of subjects with arrhythmogenic right ventricular cardiomyopathy (ARVC) at higher risk for sudden death is an unresolved issue. An influence of the autonomic activity on the genesis of ventricular arrhythmias was postulated. Heart rate variability (HRV) analysis provides a useful method to measure autonomic activity, and is a predictor of increased risk of death after myocardial infarction. For these reasons, the aim of the study was to evaluate HRV and its correlations with ventricular arrhythmias, heart function, and prognostic outcome in patients with ARVC. The study included 46 patients with ARVC who were not taking antiarrhythmic medications. The diagnosis was made by ECG, echocardiography, angiography, and endomyocardial biopsy. Exercise stress test and Holter monitoring were obtained in all patients. Time-domain analysis of HRV was expressed as the standard deviation of all normal to normal NN intervals (SDNN) detected during 24-hour Holter monitoring. Thirty healthy subjects represented a control group for HRV analysis. The mean follow-up was 10.8 +/- 1.86 years. SDNN was reduced in patients with ARVC in comparison with the control group (151 +/- 36 vs 176 +/- 34, P = 0.00042). Moreover, there was a significant correlation of this index with the age of the patients (r = - 0.59, P < 0.001), with the left (r = 0.44, P = 0.002) and right (r = 0.47, P = 0.001) ventricle ejection fraction, with the right ventricular end diastolic volume (r = - 0.62, P < 0.001), and with the ventricular arrhythmias, detected during the same Holter record used for HRV analysis (patients with isolated ventricular ectopic beats < 1,000/24 hours, 184 +/- 34; patients with isolated ventricular ectopic beats > 1,000/24 hours and/or couplets, 156 +/- 25; patients with repetitive ventricular ectopic beats (> or = 3) and/or ventricular tachycardia, 129 +/- 25; P < 0.001). During follow-up two patients showed a transient but significant reduction of SDNN and a concomitant increase of the arrhythmic events. In eight patients an episode of sustained ventricular tachycardia occurred, but the mean SDNN of this subgroup did not differ from the mean value of the remaining patients (152 +/- 15 vs 150 +/- 39; P = NS). Only one subject died after heart transplantation during follow-up (case censored). Time-domain analysis of HRV seems to be a useful method to assess the autonomic influences in ARVC. A reduction of vagal influences correlates with the extent of the disease. The significant correlation between SDNN and ventricular arrhythmias confirmed the influences of autonomic activity in the modulation of the electrical instability in ARVC patients. However, SDNN was not predictive of spontaneous episodes of sustained ventricular tachycardia.     

Multiplane two-dimensional strain echocardiography for segmental analysis of right ventricular mechanics

Introduction

Recent studies showed the prognostic value of strain measurements of the free right ventricular (RV) wall. The aim of this study was to evaluate the feasibility and the diagnostic value of the assessment of longitudinal mechanics of all segments of the RV by multiplane, two-dimensional transthoracic (2D) strain echocardiography.

Methods

A triplane apical visualization of the RV was attempted in each individual. RV systolic function was assessed with RV 2D strain, RV automated systolic index, real-time 3D echocardiography and RV parameters according to current guidelines.

Results

The study population (n = 118) consisted of 81 consecutive patients with overt right ventricular systolic dysfunction due to different etiologies, 13 patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and 24 healthy controls. Triplane assessment of the RV was possible in all examinations. 2D strain of 18 segments could be obtained in 75 %, 9 segments of the RV free wall in 84 % and 3 segments in four-chamber view in 96 % of the examinations. Contrary to established RV parameters, RV 2D strain detected impaired RV function in all patient groups compared to the control group. In regard to global RV function, RV 2D strain by multiplane assessment was not superior to a monoplane approach. However, segmental strain analysis was able to define the presence of impaired RV function in ARVC patients which otherwise would have been missed by current standard parameters.

Conclusion

Regional RV mechanics were reliably assessed by RV 2D strain in a multiplane apical chamber view mode.     

Signal-averaged electrocardiographic parameter progression as a marker of increased electrical instability in two cases with an overt form of arrhythmogenic right ventricular cardiomyopathy

In arrhythmogenic right ventricular cardiomyopathy (ARVC) the fibrofatty substitution of the RV myocardium constitutes the substrate for reentrant circuits, leading to the onset of ventricular arrhythmias. This pathological process also accounts for "delayed ventricular potentials" that could be recorded as late potentials using the signal-averaged ECG technique (SAECG). This study examined two patients affected by overt forms of ARVC who showed a worsening of the electrical instability associated with a fast progression of SAECG parameters, while all the other clinical findings remained unchanged. This suggests a possible role of SAECG parameter progression as a marker of increased electrical instability.     

Concordance between an electroanatomic mapping system and cardiac MRI in arrhythmogenic right ventricular cardiomyopathy

A 29-year-old man presenting with syncopal ventricular tachycardia was diagnosed with arrhythmogenic right ventricular (RV) cardiomyopathy. Cardiac magnetic resonance imaging (MRI) revealed an unequivocal dyskinetic segment at the basal portion of the RV lateral free wall. Three-dimensional electroanatomic voltage mapping using the EnSite NavX system recorded a low voltage area corresponding to the diseased portion of the right ventricle identified by MRI. This report describes concordance between cardiac MRI and this novel mapping system in arrhythmogenic RV cardiomyopathy.     

Ablation of nonsustained or hemodynamically unstable ventricular arrhythmia originating from the right ventricular outflow tract guided by noncontact mapping

Conventional activation or pacemapping is effective in guiding ablation of ventricular tachyarrhythmia originating from right ventricular outflow tract (RVOT). However, in selected patients with hemodynamically unstable or nonsustained tachycardia, noncontact mapping may be an effective alternative method to guide ablation in RVOT. Five patients with symptomatic hypotension during ventricular tachycardia (VT) or nonsustained tachyarrhythmia originating from the RVOT had radiofrequency ablation guided by noncontact mapping. All patients had a history of syncope and the tachyarrhythmias were refractory to antiarrhythmic therapy. Four patients had spontaneous sustained VT of a cycle length from 250 to 300 ms and one had symptomatic ventricular ectopic beats. Two patients were diagnosed to have arrhythmogenic right ventricular cardiomyopathy (ARVC). Sustained VT with hypotension was induced in two patients and nonsustained VT in three patients. Isopotential color maps were used to locate the earliest activation site of the tachyarrhythmia in RVOT. Three patients had tachyarrhythmia exit sites at the septal region and two at lateral region of RVOT. Low voltage area and diastolic activity were detected in the two patients with ARVC. Radiofrequency ablation guided by noncontact mapping was performed during sinus rhythm in all patients. The number of ablation attempts ranged from 1 to 14. After follow-up for 12 +/- 5.8 months, there was no recurrence of tachyarrhythmia and syncope in all five patients. Noncontact mapping is a safe and effective alternative method to guide ablation of hemodynamically unstable or nonsustained ventricular arrhythmia originating from RVOT.     

Reversible right ventricular dysfunction in patients with HIV infection

Human immunodeficiency virus-related cardiomyopathy is characterized by global left ventricular (LV) dysfunction commonly associated with biventricular dilation. Human immunodeficiency virus (HIV) cardiomyopathy carries a poor prognosis, and the role of antiretroviral therapy in the reversal of heart failure is not very clear. We report two patients with HIV infection who presented with severe right ventricular (RV) dysfunction in the absence of pulmonary parenchymal, pulmonary arterial and left ventricular myocardial involvement. During the period of intensive antiretroviral therapy, the symptoms of right heart failure progressively and remarkably improved. This was accompanied by normalization of right ventricular size and RV function documented by repeat echocardiograms. Given that the serologic tests for opportunistic infections were negative, and the RV function improvement correlated with a decrement in the viral load, it is likely that the cardiomyopathy was due to direct infection by HIV. These cases illustrate that there can be isolated involvement of the right heart in the absence of lung, significant pulmonary vascular and left ventricular disease, and also that the antiretroviral therapy might reverse the cardiomyopathy.     

Ablation of epicardial right ventricular tachycardia provoked by proarrhythmic RV pacing in a patient with dilated cardiomyopathy

Ventricular arrhythmias are common in the setting of nonischemic dilated cardiomyopathy (NIDCM). However, the characterization of the substrate and mechanism of epicardial ventricular tachycardia (VT) associated with NIDCM is limited, and to the best of our knowledge VT due to myocardial reentry within the right ventricular (RV) epicardium associated with NIDCM has not been reported. We report a case of RV epicardial VT provoked by RV pacing that was successfully ablated.     

Biventricular myocardial strain analysis in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) using cardiovascular magnetic resonance feature tracking

Background

Fibrofatty degeneration of myocardium in ARVC is associated with wall motion abnormalities. The aim of this study was to examine whether Cardiovascular Magnetic Resonance (CMR) based strain analysis using feature tracking (FT) can serve as a quantifiable measure to confirm global and regional ventricular dysfunction in ARVC patients and support the early detection of ARVC.

Methods

We enrolled 20 patients with ARVC, 30 with borderline ARVC and 22 subjects with a positive family history but no clinical signs of a manifest ARVC. 10 healthy volunteers (HV) served as controls. 15 ARVC patients received genotyping for Plakophilin-2 mutation (PKP-2), of which 7 were found to be positive. Cine MR datasets of all subjects were assessed for myocardial strain using FT (TomTec Diogenes Software). Global strain and strain rate in radial, circumferential and longitudinal mode were assessed for the right and left ventricle. In addition strain analysis at a segmental level was performed for the right ventricular free wall.

Results

RV global longitudinal strain rates in ARVC (−0.68 ± 0.36 sec⁻¹) and borderline ARVC (−0.85 ± 0.36 sec⁻¹) were significantly reduced in comparison with HV (−1.38 ± 0.52 sec⁻¹, p ≤ 0.05). Furthermore, in ARVC patients RV global circumferential strain and strain rates at the basal level were significantly reduced compared with HV (strain: −5.1 ± 2.7 vs. -9.2 ± 3.6%; strain rate: −0.31 ± 0.13 sec⁻¹ vs. -0.61 ± 0.21 sec⁻¹). Even for patients with ARVC or borderline ARVC and normal RV ejection fraction (n=30) global longitudinal strain rate proved to be significantly reduced compared with HV (−0.9 ± 0.3 vs. -1.4 ± 0.5 sec⁻¹; p < 0.005). In ARVC patients with PKP-2 mutation there was a clear trend towards a more pronounced impairment in RV global longitudinal strain rate. On ROC analysis RV global longitudinal strain rate and circumferential strain rate at the basal level proved to be the best discriminators between ARVC patients and HV (AUC: 0.9 and 0.92, respectively).

Conclusion

CMR based strain analysis using FT is an objective and useful measure for quantification of wall motion abnormalities in ARVC. It allows differentiation between manifest or borderline ARVC and HV, even if ejection fraction is still normal.     

Clinical significance of right ventricular dysfunction in left ventricular non-compaction cardiomyopathy

Left ventricular non-compaction (LVNC) is described as the persistence of trabeculated myocardium in the left ventricle (LV) and is optimally assessed by cardiac magnetic resonance (CMR). Right ventricular (RV) involvement in LVNC remains poorly studied. Consecutive patients (N = 14) diagnosed with LVNC by CMR were studied. Their clinical data were analyzed. In addition, CMR assessment included quantification of LV and RV volumes, mass, ejection fraction (EF), LV wall motion score, LV non-compacted segments and non-compacted to compacted myocardium ratios. Average age of presentation was 33.1 ± 17.6 years old, with 9 males (64%). Of these patients, 7 (50%) presented with acute heart failure and 3 (21%) with syncope, including 1 documented ventricular tachycardia. RV EF < 35% was identified in 7 (50%) of these patients. Patients with RV EF < 35% presented at a higher median New York Heart Association class (1 [IQR 1-2] vs. 3 [IQR 2-4], P = 0.021) and had significantly lower LV EF (50.7% ± 15.4 vs. 21.8% ± 19.9, P = 0.029), higher LV end diastolic (100.9 ml/m(2) ± 22.3 vs. 159.1 ml/m(2) ± 36.0, P = 0.002) and systolic volume indices (52.0 ml/m(2) ± 25.8 vs. 129.1 ml/m(2) ± 48.4, P = 0.002), higher LV wall motion score index (1.3 ± 0.5 vs. 2.2 ± 0.6, P = 0.004) and higher ratio of LV non-compacted to compacted myocardium (3.3 ± 0.6 vs. 4.1 ± 0.8, P = 0.026). All 4 patients that had ventricular tachycardia also had RV dysfunction. RV dysfunction was present in half of patients with LVNC. Significant RV dysfunction seems to be a marker of advanced LVNC and may carry a worse prognosis. Further studies in a larger sample of patients are needed to confirm those observations.     

致心律不齐性右心室型心肌病患者右心室室壁脂肪浸润或纤维化程度与右心室功能及容积的相关性

目的 探讨致心律不齐性右心室型心肌病（ARVC）患者右心室室壁脂肪浸润或纤维化程度与右心室功能及容积的相关性。方法 对20例ARVC患者行多序列MR扫描,测量左右心室流出道横径、左右心室舒张末横径（EDD）、左右心室射血分数（EF）、左右心室舒张末容积指数（EDVI）、左右心室收缩末容积指数（ESVI）、左右心室心输出量指数（CI）、右心室心肌质量指数（MASSI）及室壁脂肪浸润或纤维化程度情况,采用线性相关分析观察右心室室壁脂肪浸润或纤维化程度与右心室功能及容积的相关性。结果 ARVC患者右心室流出道横径（52.42±11.80） mm,右心室EDD、EF、EDVI、ESVI、CI、MASSI分别为（50.13±8.71） mm、（18.13±6.71）%、（169.13±72.11） ml/m²、（117.01±67.31） ml/m²、（1.81±0.20） L/（min·m²）、（17.62±1.80） g/m²。20例右心室游离壁/前壁均受累,10例下壁受累,14例心尖部受累,15例右心室流出道受累;右心室室壁脂肪浸润或纤维化指数（70.00±22.33）%,与右心室EF值呈负相关（r=-0.627,P=0.003）,与右心室EDVI（r=0.695,P=0.001）和ESVI均呈正相关（r=0.676,P=0.001）。结论 右心室室壁脂肪浸润或纤维化程度与右心室功能及容积的相关性可反映ARVC患者心脏功能变化。     

致心律失常性右室心肌病20例临床分析

目的:探讨致心律失常性右室心肌病(ARVC)的临床和心电图特点。方法:收集、查阅2002-2005年20例诊断为ARVC患者入院病例资料,常规行临床资料、心电图、超声心动图、X线胸片、24h动态心电图及心内电生理检查的资料分析。结果:20例ARVC患者中有晕厥发作(65%)、心悸(100%)、频发室性早搏(100%)、右心室源性短阵室速(85%)。20例患者常规心电图检查中15例(75%)有右束支传导阻滞(RBBB),12例(60%)电轴右偏,7例(35%)出现Epsilon波,17例(85%)胸前导联V1～V3T波倒置,13例(65%)V1导联QRS波时限≥110ms,12例(60%)(V1+V2+V3导联QRS波时限之和)/(V4+V5+V6导联QRS波时限之和)比值>1.2。在无RBBB时,18例(90%)胸前导联V1～V3均可见延长的S波升支≥55ms。超声心动图示右心房内径为(48.00±8.81)mm,右心室内径为(50.90±10.30)mm,右心功能减退,射血分数为0.301±0.090。结论:ARVC多有发作性晕厥,心电图上可出现频发室早及呈左束支传导阻滞型室速,窦性心律时伴RBBB型或电轴...