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Background Mutations in the cardiac troponin T gene causing familial hypertrophic cardiomyopathy (HCM) are associated with a very poor prognosis but only mild hypertrophy. To date, the serial morphologic changes in patients with HCM linked to cardiac troponin T gene mutations have not been reported. Hypothesis The aim of this study was to determine the long-term course of patients with familial HCM caused by the cardiac troponin T gene mutation, Arg92Trp. Methods In all, 140 probands with familial HCM were screened for mutations in the cardiac troponin T gene. Results The Arg92Trp missense mutation was present in 10 individuals from two unrelated pedigrees. They exhibited different cardiac morphologies: three had dilated cardiomyopathy-like features, five had asymmetric septal hypertrophy with normal left ventricular systolic function, one had electrocardiographic abnormalities without hypertrophy, and one had the disease-causing mutation but did not fulfill the clinical criteria for the disease. The mean maximum wall thickness was 14.1 +/- 6.0 mm. The three patients with dilated cardiomyopathy-like features had progressive left ventricular dilation. Three individuals underwent right ventricular endomyocardial biopsy. There was a modest degree of myocardial hypertrophy (myocyte diameter: 18.9 +/- 5.2 microm), and minimal myocardial disarray and mild fibrosis were noted. Conclusion The Arg92Trp substitution in the cardiac troponin T gene shows a high degree of penetrance, moderate hypertrophy, and early progression to dilated cardiomyopathy in Japanese patients. Early identification of individuals with this mutation may provide the opportunity to evaluate the efficacy of early therapeutic interventions.

Background: In patients with essential hypertension (HT), proportional (symmetric) left ventricular hypertrophy (LVH) is common. In contrast, hypertrophic cardiomyopathy (HCM) is characterized by disproportional LVH and, in particular, asymmetric septal hypertrophy (ASH); however, some hypertensive patients also develop ASH. It has not been determined whether such cases represent a distinct type of hypertensive LVH or HCM combined with hypertension. Hypothesis: The study was undertaken to evaluate sympathetic activity in the interventricular septum in patients with HT and ASH or in patients with HCM. Methods: The patients were evaluated by I–123 metaiodobenzylguanidine (MIBG) and thallium-201 (201Tl) single-photon emission computed tomography (SPECT), respectively. They were divided into three groups: patients with essential HT and symmetric septal hypertrophy (Group A), patients with HT and ASH (Group B), and patients with HCM and ASH (Group C). Results: Compared with the lateral wall, early uptake of MIBG in the septum was significantly higher in Group B than in Group A, but not significantly different between Groups A and C. Compared with the lateral wall, early uptake of 201Tl in the septum did not differ among the three groups. No significant difference in the MIBG clearance in the lateral wall was seen among the three groups. By contrast, MIBG clearances in the septum and apex were significantly greater in Group C than in Groups A and B. There was an inverse correlation between systolic thickening and MIBG clearance in the septum. Conclusion: These findings suggest that sympathetic activity in the septum differs between patients with HT and ASH and patients with HCM.

Laparoscopy assisted colectomy with extracorporeal anastomosis was carried out in five patients. In three patients, the lesions were carcinoma with submucosal invasion and the histological results of the polypectomy specimen indicated the necessity of the subsequent colectomy. In the other two patients the lesions were either adenoma or carcinoma in adenoma. Under pneumoperitoneum, mobilization of the colon was performed using the laparoscopic technique. In three patients the mesenteric vessels of a segment of the colon were ligated and divided extracorporeally. In two patients the mesenteric vessels were clipped and divided intracorporeally. In all cases, extracorporeal resection of the colon and hand suture anastomosis were performed. Surgery time ranged from 3 hours and 20 minutes to 4 hours and 50 minutes. No postoperative complications were experinced. Four patients began to walk on the first postoperative day. Postoperative administration of analgesics was needed in four patients for two days or less after the operation. In all but one case, bowel sounds were audible from the first post-operative day onwards. In only one patient was the postoperative recovery delayed. Although sufficient future studies should be accumulated to confirm the advantages of this procedure, we can expect that laparoscopy assisted colectomy will become a useful procedure for benign and early malignant lesions in which colonoscopic removal was not possible or was suspected to be insufficient. (Dig Endosc 1944; 6 : 52–58)