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Objective: To investigate the importance of transthyretin (TTR) gene mutations in explaining the phenotypic expression in patients diagnosed with hypertrophic cardiomyopathy (HCM) in northern Sweden., Background: Hypertrophic cardiomyopathy is relatively common and often caused by mutations in sarcomeric protein genes. Mutations in the TTR gene are also common, one of which causes familial amyloid polyneuropathy (FAP), with peripheral polyneuropathy and frequently, cardiac hypertrophy. These circumstances were highlighted by the finding of an index case with amyloidosis, presenting itself as HCM. Initial rectal and fat biopsies did not show amyloid deposits. Later on, the patient was shown to carry a TTR gene mutation, and cardiac amyloidosis was confirmed by myocardial biopsy. Only then was a repeated fat biopsy positive for amyloid deposits., Design: Cross-sectional study., Setting: Cardiology tertiary referral centre., Subjects: Forty-six unrelated individuals with HCM and the index case were included. Common diagnostic criteria for HCM were used. The 46 patients with HCM were previously analysed for mutations in eight sarcomeric protein genes and the TTR gene was now analysed by denaturing high-performance liquid chromatography and direct sequencing., Results: One mutation in the TTR gene (Val30Met) was found in three individuals and the index case., Conclusions: Three of the 46 cases with HCM carried the Val30Met mutation, and were considered likely to have cardiac amyloidosis, like the index case. As a correct diagnosis of cardiac amyloidosis is mandatory for a potentially life-saving treatment, TTR mutation analysis should be considered in cases of HCM not explained by mutations in sarcomeric protein genes.

Impairment of left ventricular (LV) function has previously been reported in patients with systemic sclerosis (SScl). An intermittent vasospastic process in the myocardium may contribute to the development of myocardial dysfunction. Vasodilators may therefore be potentially useful in the treatment of cardiac dysfunction in patients with SScl. This study was designed to evaluate the long-term effects of captopril on the myocardial function of patients with SScl. Twenty-two patients with SScl (15 patients with diffuse scleroderma and 7 patients with CREST syndrome, i.e. calcinosis. Raynaud's phenomenon, oesophageal hypomotility, sclerodactyly, telangiectasia) were investigated by means of Doppler and echophonocardiography before and after treatment with captopril (1.3 mg kg-1 body weight d-1) for 11-15 months. There were no significant differences in heart rate, systolic and diastolic blood pressure, end-systolic blood pressure, total peripheral resistance or LV diameters before or after treatment. However, captopril treatment exerted significant effects on LV function: the pre-ejection period (PEP) and the ratio of pre-ejection period to LV ejection time decreased significantly (P less than 0.05). Mitral E-point septal separation decreased significantly (P less than 0.01), even after adjustment for LV end-diastolic diameter (P less than 0.01). The ejection fraction increased significantly (P less than 0.05), and the isovolumic relaxation time decreased (P less than 0.01). The left atrial emptying index increased (P less than 0.01). The Doppler peak late to early ventricular filling velocity decreased (P less than 0.05), and the isovolumic index was also reduced (P less than 0.05). We conclude that both systolic and diastolic LV function indices improved in patients with SScl after captopril treatment for a mean period of 1 year. The effects of captopril might be due to vasodilation of the myocardial vessels and/or a direct effect on the renin-angiotensin system of the heart.

To evaluate the extent of left ventricular (LV) diastolic impairment in systemic sclerosis, we examined 30 consecutive patients (15 men and 15 women) with this condition, and compared the findings with the data for 48 age- and sex-matched randomly sampled controls. All patients were investigated by phonocardiography, pulse curve recording, and M-mode echocardiography. Twenty-three of 30 (77%) patients had LV hypertrophy and/or diastolic impairment. Interventricular septum (P = 0.0001), LV posterior wall (P less than 0.05), and the wall thickness to cavity dimension ratio (P less than 0.001) were increased in patients compared to controls, as was LV mass index (P less than 0.002). Five patients had asymmetric septal hypertrophy. LV end-diastolic dimension did not differ between groups. LV distensibility was impaired, as judged from apexcardiographic a/H ratio (P less than 0.05) and from an increased left atrial index (P less than 0.005). LV early filling was impaired, with a reduced left atrial emptying index (P = 0.0001), and a reduced rate of dimension increase in digitized M-mode (P less than 0.02). We found no evidence of impaired LV relaxation. Blood pressure did not differ between patients and controls. With longer duration of the disease, left atrial dimension appeared to increase (r = 0.42, P less than 0.05), while other variables were not related to disease duration. The impaired LV filling was not secondary to systolic dysfunction. We conclude that systemic sclerosis patients have an increased LV wall thickness, with impaired early filling properties and LV distensibility.