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Young Stroke: An Unusual Presentation of Arrhythmogenic Right Ventricular Dysplasia
Correspondence Address: Source of Support: None, Conflict of Interest: None DOI: 10.4103/0028-3886.273639
Keywords: Arrhythmogenic right ventricular dysplasia, cerebrovascular accident, magnetic resonance imaging, right ventricle
Sir, Only 3 decades have passed since the initial description of the clinical profile of arrhythmogenic right ventricular dysplasia (ARVD) by Fontaine and co-workers.[1] Since then, this entity has been found to have a prevalence of about 1 in 5000 individuals [2] and is well recognized all over the world including in the U.S., Europe and Asia. The usual clinical presentation of ARVD is that of palpitations, nonsustained or sustained ventricular tachyarrhythmia and sudden cardiac death.[3] Most patients with this condition experience the onset of these symptoms between the ages of 20 and 40 years, and the disease shows a predisposition to occur in men.[4] A familial incidence is also noted in the description of the disease.[5] The pathophysiology of arrhythmogenic right ventricular dysplasia (ARVD) is still poorly understood and is often an underdiagnosed cardiomyopathy.[6] A 23-year-old gentleman (a Hindu priest) was brought to the emergency room with complaints of sudden onset vomiting and headache followed by a slurring of his speech, an inability to open his eyes with progressive weakness of all four limbs. He did not have any clinical symptoms previously. He was found to have delirium with bilateral ptosis, unequal pupils, and quadriparesis of the upper motor neuron-type disease clinically. He underwent a MRI of the brain with contrast study including MR angiography of the brain which revealed bilateral brainstem and cerebellar acute ischemic infarcts without any evidence of hemorrhage/hemorrhagic transformation of infarcts and normal intracranial major vessels [Figure 1]. With the bilateral ischemic infarcts in brain and the younger age of the patient, the possibility of cardioembolic event was considered and cardiac evaluation was initiated.
The patient did not have any cardiac symptoms or any family history of cardiac disease in the past. On admission, he was hemodynamically stable and was not in heart failure. ECG revealed sinus tachycardia with frequent ventricular premature complexes of Left Bundle Branch Block (LBBB) morphology and right atrial enlargement with T-wave inversions in V1–V4 leads [Figure 2]. His cardiac enzymes (troponin I and CPK–CPK MB) and D-dimer results were normal. The initial chest X-ray was normal.
Subsequently, echocardiography was done which showed a dilated right atrium and right ventricle with thinning and outpouchings of right ventricular free wall with marked right ventricular systolic dysfunction. Left ventricular posterior wall was also hypokinetic with overall mild left ventricular (LV) systolic dysfunction. The interventricular septum had paradoxical motion consistent with right ventricular (RV) volume overload. There were no intracardiac clots or septal defects to support a cardioembolic event [Figure 3]. A transesophageal echocardiographic (TEE) study was done which ruled out intracardiac clot and right-to-left shunt (on contrast study with adequate valsalva maneuver).
With the suspicion of ARVD on echocardiography, a cardiac MRI was done. On ECG-gated cine MR images, there was diffuse global hypokinesis of the right ventricular free wall with severe RV systolic dysfunction (Right Ventricular Ejection Fraction (RVEF) =25%). The thinning of the RV free wall with multiple outpouchings was noted. The delayed enhancement images revealed contrast enhancement of the thinned out right ventricular free wall compatible with fibro-fatty degeneration of the same [Figure 4]. Predominant RV involvement with thinned out RV free wall and multiple outpouchings of the RV free wall with delayed enhancement of RV free wall confirmed the diagnosis of ARVD.
Subsequently, 24-hour Holter monitoring was done which revealed a sinus rhythm with frequent ventricular premature contractions (total VPCs = 3892) of LBBB and Right Bundle Branch Block (RBBB) morphology (predominantly LBBB morphology) without obvious ventricular or atrial tachyarrhythmia. He was treated with antiplatelets, statin, anticoagulation, and β-blockers. He has been under medical follow-up for the last 2 years without recurrence of stroke or significant cardiac symptoms. ARVD is an idiopathic cardiomyopathy characterized by the progressive thinning and fibro-fatty degeneration of the right ventricle with resulting RV dysfunction.[7] Involvement of the left ventricle is less common and usually occurs in the terminal stages.[7] ARVD accounts for about 20% cases of sudden cardiac deaths in young individuals between 20 and 40 years with a further higher prevalence in young athletes.[8] The usual presenting symptoms range from mild palpitations to syncope and sudden cardiac death.[8] The overt electrical abnormalities include isolated VPCs to sustained ventricular tachycardia with LBBB morphology or ventricular fibrillation leading to cardiac arrest.[8] The common findings in baseline ECG are inverted T waves in right precordial leads (V1, V2, and V3) or beyond in individuals >14 years of age. QRS duration of >110 ms and Epsilon wave in right precordial leads are strongly indicative of ARVD. ECG during tachycardia classically reveals ventricular tachycardia of LBBB morphology with superior axis.[9] Echocardiography may demonstrate RV dilatation with thinning and outpunching of the RV free wall with RV systolic dysfunction.[9] Fibro-fatty replacement of RV myocardium in endomyocardial biopsy or cardiac MRI is diagnostic of ARVD.[9] The therapeutic management of patients with ARVD has evolved over the years and continues to be an important challenge. It requires lifelong treatment. Therapeutic options consist of lifestyle changes, pharmacological treatment, catheter ablation, Implantable Cardioverter Defibrillator (ICD), and heart transplantation. Patients with a definite diagnosis of ARVD should be restricted from participation in competitive sports, with the possible exception of recreational low-intensity sports. Pharmacological options in ARVC treatment consist of antiarrhythmic agents, β-blockers, and heart failure drug therapy. Because studies are not available to compare the efficacy of individual β-blockers and to define the most effective dosage, we recommend using nonvasodilating β-blockers titrated to the maximum tolerated dose for age and weight. For ARVD patients who developed right- and/or left-sided heart failure, standard pharmacological treatment with angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, β-blockers, and diuretics is recommended by European guidelines. Long-term oral anticoagulation is generally indicated for secondary prevention in patients with documented intracavitary thrombosis or venous/systemic thromboembolism. Prophylactic anticoagulation for primary prevention of thromboembolism on the basis of ventricular dilatation/dysfunction, either global or regional, is not recommended. Implantation of an ICD is recommended in ARVD patients who have experienced ≥1 episode of hemodynamically unstable, sustained Ventricular Tachycardia (VT) or Ventricular Fibrillation (VF) and for patients with severe systolic dysfunction of the RV, LV, or both, irrespective of arrhythmias. Catheter ablation of VT is recommended in ARVD patients with incessant VT or frequent appropriate ICD interventions on VT despite maximal pharmacological therapy, including amiodarone. Heart transplantation is recommended as a final therapeutic option in patients with either severe, unresponsive congestive heart failure or recurrent episodes of VT/VF which are refractory to catheter (and surgical) ablation in experienced centers and/or ICD therapy.[10] Our patient is a young gentleman presenting with acute ischemic stroke. Following the initial evaluation, suspicion of ARVD came only when the echocardiographic study revealed features suggestive of RV cardiomyopathy. On further evaluation, our patient fulfilled two major and one minor Task Force criteria [9] for ARVD: RV dysfunction with thinning/multiple outpouchings and fibro-fatty degeneration of the RV free wall, repolarization abnormalities in the ECG, and frequent VPCs in the Holter study. However, our patient is unique since he presented with acute bilateral ischemic stroke consistent with cardioembolic phenomenon which is a rare initial presentation of ARVD. Possible mechanisms of Cerebrovascular Accident (CVA) in a case of ARVD may be one of the following:
The detailed clinical examination and imaging in our patient was done to diagnose any of these possibilities. Transthoracic and TEE evaluation ruled out possibilities of thrombus or right-to-left shunt. MR angiography of brain and neck arteries ruled out vascular malformations. Transient cerebral hypoperfusion secondary to ventricular tachyarrhythmia leads to ischemia in a typical “water-shed” distribution which was not present in this case. The ECGs and the Holter study did not document atrial fibrillation. Atrial fibrillation is usually seen in the late stages of ARVD, and is especially associated with significant biventricular failure.[11] Initial presentation with atrial fibrillation rather than ventricular tachyarrhythmia is less common. Our patient did not have significant LV dysfunction or left atrial dilatation in the echocardiographic study. Paroxysmal atrial fibrillation can be the underlying mechanism for thromboembolism. There is a scarcity of data regarding cerebrovascular embolism in ARVD cases [Table 1].
Owing to their large size, cardiac emboli flow to the intracranial vessels in most cases and cause massive, superficial, single large striatocapsular, or multiple infarcts in the middle cerebral artery. Therefore, cardioembolic infarctions predominate in the carotid and middle cerebral artery distribution territories. Of emboli to the brain, approximately 80% involve the anterior circulation (i.e., carotid artery territory), whereas 20% involve the vertebrobasilar distribution, proportional to the distribution of cerebral blood flow.[12] Elzbieta et al.[13] noticed thromboembolic complications in 4% of patients with ARVD with an annual incidence of 0.5/100 patients. Out of 126 patients, 2 had pulmonary emboli, 1 patient had a thrombus in the RV outflow tract, whereas 2 patients with atrial fibrillation had CVA. Hence, in the absence of other possibilities, paroxysmal atrial fibrillation with cardioembolic phenomenon is the most convincing mechanism of ischemic stroke in our patient. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1]
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