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Background: Chronic progressive external ophthalmoplegia (CPEO), which includes Kearns-Sayre syndrome, is a mitochondrial disorder with large deletions of mitochondrial DNA. Recently, mtDNA deletions in cardiac muscle cells were thought to be a cause of dilated cardiomyopathy. However, the cardiac involvement in patients with CPEO is generally considered to be limited to the cardiac conduction system. Hypothesis: The purpose of this study was to evaluate left ventricular function in patients with CPEO. Methods: We evaluated the cardiac function of five patients with CPEO by means of carotid pulse recording and Doppler echocardiography. Results: The ratio of the pre-ejection period to ejection time was increased to 0.67 in one patient and to 0.50 in another. Echocardiography showed left ventricular dilatation and diffuse hypokinetic wall motion in both cases. Left ventricular fractional shortening was decreased to 5 and 19%, respectively, and the mean rate of circumferential shortening was decreased to 0.12 and 0.63 circ/s, respectively. One of the two patients died of congestive heart failure 2 months after the study. The Doppler pattern of left ventricular filling in the three remaining patients showed a decrease in the ratio of peak flow velocity in early diastole to that in late diastole, with an increase in deceleration time. Conclusion: Although cardiac involvement in patients with CPEO is generally considered to be limited to the cardiac conduction system, left ventricular dysfunction may be present and should receive more attention in the management of patients with CPEO.

OBJECTIVES Mutational analysis of the sterol 27-hydroxylase ( CYP27 ) gene was performed on three patients from two Japanese families who had cerebrotendinous xanthomatosis (CTX) associated with parkinsonism. METHODS Clinical evaluations, brain MRI studies, and laboratory analyses were completed on the three patients. The CYP27 gene was analysed for mutations by PCR amplification of gene segments followed by direct sequencing. RESULTS Two different, homozygous mutations were identified in these families. One is a novel transition, substituting T for G at Glu162 (GAG) resulting in a stop codon (TAG). The other is also a transition, substituting T for C at Arg441 (CGG) resulting in Trp (TGG). The second is located in two amino acids ahead of the heme ligand binding site (Cys443) of the protein likely rendering it non-functional. It is the most common CTX mutation in Japanese patients. CONCLUSIONS CTX with parkinsonism is caused by mutations with a severe impact on enzyme function. The two mutations described here are likely to cause loss of function because they are chain terminating or affect an essential site in the protein.