A 45-year-old previously healthy male with a known history of polysubstance use (tobacco, ethanol, and cocaine) presented to the emergency department with sudden onset left-sided facial droop, hemiparesis, hemisensory loss, and dysarthria. The patient reported using cocaine twelve hours previously. On arrival, the EKG revealed complete atrial ventricular dissociation with a ventricular escape rhythm at a rate of 45 beats/minute with right bundle branch morphology and a QRS interval of 158 ms. Although his initial national institute of stroke scale was 6, his neurologic deficits resolved spontaneously within 60 minutes of presentation without administration of tissue plasminogen activator. Laboratory studies were notable for positive cocaine in urine, normal CBC, electrolytes, blood glucose, hepatic and renal function, lipid and coagulation panel, TSH, and Troponin I. MRI of brain revealed small acute infarcts in the right external capsule and basal ganglia with suspected thrombus or embolism in the distal right M1 segment. Transthoracic echocardiogram revealed an ejection fraction (EF) of 19% and a severely dilated left ventricle with global hypokinesis and moderate mitral regurgitation. As no evidence of coronary artery disease was demonstrated with coronary angiogram, the patient was diagnosed with dilated cardiomyopathy of unknown etiology. Third degree AV block secondary to central cerebral parasympathetic/vagal stimulation was considered in the differential. However, the patient remained neurologically intact with a persistent arrhythmia for several days excluding this diagnosis. A cardiac MRI revealed an EF of 12% with a ratio of noncompacted to compacted myocardium of 2.3. This finding was diagnostic for noncompaction cardiomyopathy, a rare congenital abnormality that explained the patient’s left ventricular dysfunction and embolic stroke. The patient was discharged on lifelong anticoagulation after receiving cardiac re-synchronization therapy through the implant of a biventricular implantable cardioverter defibrillator.
Noncompaction cardiomyopathy is a rare congenital abnormality characterized by prominent intraventricular trabeculae secondary to failure of intrauterine ventricle formation. Common initial presentations include heart failure, ventricular and atrial arrhythmias, and thromboembolism. Noncompaction cardiomyopathy complicated by both thromboembolic stroke and complete heart block has not been described in the literature. A diagnosis of noncompaction cardiomyopathy should be considered in the differential for an otherwise healthy patient presenting with these findings. Therapies that follow the diagnosis include: ICD for sudden cardiac death prevention, cardiac re-synchronization to address the heart block and improve EF in patients with RBBB morphology with a QRS > 150 ms, and lifelong anticoagulation for recurrent stroke prevention.
A diagnosis of noncompaction cardiomyopathy should be considered in the differential for an otherwise healthy patient presenting with concurrent embolic stroke and complete atrioventricular block.