European Journal of Cardiovascular Medicine

Right ventricular dysfunction could be acute and/or chronic. Massive pulmonary embolism, severe LV dysfunction and right ventricular infarction commonly with inferior wall myocardial infarction are well known causes of right ventricle dilatation and dysfunction. Atrial septal defect is another common cause of long-standing right ventricle dilatation. Rare causes are arrhythmogenic cardiomyopathy principally with ventricular arrhythmia, giant cell myocarditis, eosinophilic with hypersensitivity reaction and lymphocytic myocarditis. Few cases of isolated right ventricular involvement in sarcoidosis are also reported.

Isolated right ventricle lymphocytic myocarditis is unique diagnosis. Usually the course of disease is acute fulminant and recovers with limited or no damage, as the peak myocardial inflammation subsides; however, some cases show irreversible myocardial damage. Lymphocytic myocarditis is ordinarily caused by a viral infection. Viral infections associated with the condition includes parvovirus B19, adenovirus, coxsackievirus B and enterovirus being the most frequent and many more. Rare to rare, does it progress as chronic inflammation and right ventricular dysfunction in isolation. Endomyocardial biopsy is the gold standard, but not constantly performed in these cases.

A 29 years old young female presented in out-patient with history of breathlessness on exertion (Grade 2) from last 2 years, both lower limb swelling and abdominal distention. No history of chest pain, palpitation, dizziness and syncope. No relevant family or drug history. Physical examination shows regular pulse 80bpm, BP of 124/78mmHg, Spo2 99% on room air, raised jugular venous pressure prominent ‘v’ wave, bilateral grade 3 pitting oedema, and pulsatile liver and systolic murmur in lower left parasternal area. (Figure 1) ECG shows regular rhythm, low-voltage QRS complexes and T wave inversion in anterior precordial leads with few VPCs.

Fig. 1 Showing electrocardiogram

TTE revealed massive right ventricle dilation and dysfunction with severe tricuspid regurgitation. Normal left side systolic, diastolic and valvular function. Mild pulmonary systolic pressure of 36 mmHg noted on echocardiography (Figure 2).

Transoesophageal Echocardiography was done revealed normal pulmonary vein drainage and no atrial septal defect. Routine investigations were ordered showed no significant abnormality except borderline positive HsTropT and BNP. Abdominal ultrasound showed mild ascites and mild hepatomegaly. 

Computed tomography pulmonary angiography (CTPA) and Bilateral lower limb venous Doppler showed no sign of venous thromboembolism (VTE).

Cardiac Magnetic Resonance imaging (CMR) manifest mild late gadolinium enhancement of right ventricle free wall suggestive of myocyte necrosis on top of right ventricular dysfunction (Figure 3).

Fig.3 Cardiac MR showing LGE of right ventricle free wall.

Genetic testing was done but no pathogenic or likely pathogenic variants causative of the phenotype was detected for genetic cardiomyopathies.

Ultimately, myocardial biopsy was done under fluoroscopic guidance that revealed myocardial tissue with multiple areas of fibrosis with lymphocytic infiltration i.e. chronic myocarditis. No fibrofatty replacement of myocyte. No granulomas, multinucleated giant cells or eosinophilic infiltration. Not at all, evidence of viral cytopathic changes seen (Figure 4).

Fig. 4 Myocardial biopsy with lymphocytic infiltration.

Patient was started on optimal medical treatment for heart failure for congestive symptoms and symptomatic relief. Low dose steroid therapy was moreover started.

Patient showed mild improvement in last few months only improving functional capacity but, insignificant improvement in echo findings.

We hereby presented a unique case of long standing myocarditis causing right ventricular dilatation and dysfunction where no other identifiable causes was found. Endomyocardial biopsy unveil the diagnosis of lymphocytic myocarditis. Isolated involvement of right ventricle is a rare cause, even if involved, chronic involvement is scarce. To our knowledge only two cases of acute and only one case of chronic isolated right ventricle lymphocytic myocarditis has been published in the literature. As of now immunosuppression therapy is the mainstay of treatment, corticosteroids use is controversial, not as like for eosinophilic and giant cell myocarditis. Anyhow, it is not clear whether therapy with immunosuppression is associated with cardiac function improvement or not. Dedicated case studies and long term follow up is indeed needed to clarify.

To the best of our knowledge only two cases of acute and only one case of chronic isolated right ventricle lymphocytic myocarditis has been published till date in the literature. As of now immunosuppression therapy is the mainstay of treatment, corticosteroids use is controversial, not as like for eosinophilic and giant cell myocarditis. It is not clear whether therapy with immunosuppression is associated with cardiac function improvement or not.

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