We describe a patient with relapsing polychondritis (RPC) who developed a complete heart block, mitral valve insufficiency and aortic root dilation. A 72-year-old man with a history of RPC presented with fatigue, lightheadedness and syncope, which was secondary to the new onset complete heart block (CHB). Further investigation showed an elevated C-reactive protein (CRP) level of 12.62mg/titer, erythrocyte sedimentation rate of 107mm/hour and cartilage inflammation confirmed by histology. The patient had no discernible cause for his CHB; he had no history of coronary artery disease, neuromuscular disorder, infectious disease, or metabolic derangements. Therefore, the CHB was likely a manifestation of his RPC.
Discussion:
RPC is a rare, episodic, and diffuse inflammatory disorder affecting cartilaginous tissues. Since patients are usually asymptomatic at disease onset, diagnosis is often delayed by an average of 2.9 years. Due to this delay, often times there is already significant structural and functional damage to multiple organ systems including the heart. Approximately 10% of patients with RPC have cardiac abnormalities that manifest most commonly as valvular and vascular anomalies because these structures are rich in cartilage and proteoglycan composition. However, as a systemic inflammatory disorder, RPC has the potential to affect the cardiac conduction system as well, causing varying degrees of heart block or other arrhythmias.
After diagnosis of CHB, our patient’s transthoracic echocardiogram revealed the two most common cardiac structural abnormalities associated with RPC: moderate mitral valve insufficiency and mild aortic root dilatation. Cardiac complications in RPC can be fatal; 18% of deaths in RPC are due to cardiovascular complications. In another study, 53% of patients with RPC died within 4 years of follow up due to cardiovascular complications. Due to this high morbidity and mortality, patients with RPC should be closely screened for cardiovascular disease even when they are in clinical remission. Screening tools such as annual detailed physical exams, electrocardiograms, and echocardiograms have been proposed by some authors as being effective.
Conclusions:
To date, there are only two other known cases of RPC associated heart block. This case report suggests that complete heart block should be recognized as a complication of RPC. Our case stresses the importance of keeping RPC in the differential as a cause of CHB, especially in the absence of other more common causes of CHB. Finally, close screening for cardiovascular disease is of paramount importance in patients with RPC because this disease’s ability to cause “silent inflammation”.