The role of echocardiography in diagnosing double chambered right ventricle in adults

OBJECTIVE

To evaluate the utility of echocardiography in diagnosing double chambered right ventricle (DCRV) in adults.

DESIGN

A retrospective study.

SETTING

Department of Congenital Heart Diseases and Department of Cardiac Surgery, Institute of Cardiology, Warsaw, Poland.

PATIENTS

32 patients, mean age 32.5 years, 21 female, and 11 male.

INTERVENTION

Transthoracic (TTE) and transoesophageal (TOE) echocardiographic examination in patients with suspected DCRV.

MAIN OUTCOME MEASURES

Direct inspection during surgical treatment of 28 patients diagnosed as having DCRV as an isolated lesion or associated with other pathologies.

RESULTS

Echocardiography allowed the final diagnosis of DCRV in 26 patients (81%) out of 32 studied. TTE was diagnostic in 5 (15.6%) whereas TOE was diagnostic in 21 of 21 studied by this technique. Of 6 patients with negative TTE, DCRV was identified by cardiac catheterisation in 3 and directly during surgery in the remaining 3. Of 26 patients diagnosed by echocardiography, the anomalous muscle bundle was discrete in 20 (77%) and diffuse in 6 (23%). In 23 patients (88%) right ventricular outflow obstruction was localised low in the right ventricle, and in the remaining 3 (11.5%), the obstruction was localised high in the right ventricle. Abnormal bundles localised high were discrete, bundles localised in the lower part of right ventricle were discrete in 17 (74%) and diffuse in the remaining 6 (26%). DCRV was an isolated lesion in only 2 patients (6.2%). In all subjects surgical inspection confirmed echocardiographic data.

CONCLUSIONS

Echocardiography was very useful to diagnose DCRV in adults as well as to identify its anatomic type. Comparing two different approaches, TOE better defines the entire scope of pathology, including estimation of the resultant systolic pressure gradient within the right ventricular cavity.

[Arrhythmogenic right ventricular cardiomyopathy (dysplasia): etiology, clinical presentation, diagnosis and treatment]

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disorder characterised by progressive replacement of right ventricle myocardium by either segmental or diffuse fibro-fatty tissue, often with the involvement of the left ventricular wall and manifestations of arrhythmia. Familial occurrence with autosomal dominant inheritance, variable expression and incomplete penetrance is estimated as 1/5000. The recessive form called Naxos disease has also been reported. The etiology and pathogenesis of ARVC are still unknown. Advanced theories of inflammatory or infective etiology and possible mechanism of myocyte loss through apoptosis and/or transdifferentiation into adipocytes are presented in this article. The patterns of two distinct pathomorphology of ARVC based on the nature of myocardial replacement are also presented. The presentation encompasses the wide spectrum of clinical diagnostic features of the disease, including sudden death in the family and abnormalities in ECG, Echo, MRI, angiography, PES exhibiting morphologic and functional changes, and replacement of myocytes by fibro-fatty tissue observed in endomyocardial biopsy specimens. Special attention is drawn to the subtle clinical manifestations and ECG clues of the disease in children and young people. Treatment modalities including drug therapy, ablation, implantable cardioverter defibrillators, antiarrhythmic surgery or heart transplantation are also presented.

[Increased tension on the sympathetic nervous system in arrhythmogenic right ventricular dysplasia. Participation in etiopathogenesis?]

To evaluate the suspected role of sympathetic nerve tone in pathogenesis of arrhythmogenic right ventricle dysplasia (ARVD), noradrenaline (NOR) and adrenaline (AD) plasma levels were determined by radioenzymatic method in 10 pts with ARVD (mean age 36 y, VT-8 pts, syncope-5) at rest and during peak exercise. 9 healthy men (mean age 28 y) served as control.

RESULTS

[table: see text]

CONCLUSION

Significant increase of norepinephrine serum level during peak exercise suggests essential role of sympathetic nerve tone in pathogenesis of ARVD.

[Electrocardiography of high resolution in the diagnosis of arrhythmogenic dysplasia of the right ventricle]

To assess the diagnostic value of high resolution ECG in ARVD which is a rare and diagnostically difficult disease, cardiac micropotentials were evaluated in 32 pts with ventricular arrhythmias with LBBB pattern and right axis deviation. Typical ECG-, ECHO-, angiographic features of ARVD were found in 9 pts (mean age 36 y, VT 8 pts, MAS-5). Normal right ventricle (NRV) (Echo, Tc99) was seen in 23 pts (mean age 36 y, VT-14 pts, MAS-6). 25 healthy man (mean age 28 y) served as control (C).

RESULTS

[table: see text] Morphology of total QRS complex in pts with ARVD, comparing to NRV pts and C, was exceptionally characteristic: it was composed of high frequency notches seen not only as prolonged LP but also within fundamental QRS complex.

CONCLUSION

In pts with ARVD beside presence of LP, significantly prolonged TVAT and characteristic notches within QRS complex are observed, therefore the high resolution ECG is a promising method in noninvasive diagnosis of ARVD.