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Editorial. Examines adrenergic-receptor polymorphisms and heart failure. Study by Small et al in the same issue; Causes of congestive heart failure; Sequence variation in genes within the general population; Basic components of cardiac adrenergic signaling; Higher morbidity and mortality from heart failure among black patients; Limitation to genetic-association studies.

Background: Inherited mutations cause approximately 35 percent of cases of dilated cardiomyopathy; however, few genes associated with this disease have been identified. Previously, we located a gene defect that was responsible for autosomal dominant dilated cardiomyopathy and conduction-system disease on chromosome 1p1–q21, where nuclear-envelope proteins lamin A and lamin C are encoded by the LMNA (lamin A/C) gene. Mutations in the head or tail domain of this gene cause Emery–Dreifuss muscular dystrophy, a childhood-onset disease characterized by joint contractures and in some cases by abnormalities of cardiac conduction during adulthood. Methods: We evaluated 11 families with autosomal dominant dilated cardiomyopathy and conduction-system disease. Sequences of the lamin A/C exons were determined in probands from each family, and variants were confirmed by restriction-enzyme digestion. The genotypes of the family members were ascertained. Results: Five novel missense mutations were identified: four in the α-helical rod domain of the lamin A/C gene, and one in the lamin C tail domain. Each mutation caused heritable, progressive conduction-system disease (sinus bradycardia, atrioventricular conduction block, or atrial arrhythmias) and dilated cardiomyopathy. Heart failure and sudden death occurred frequently within these families. No family members with mutations had either joint contractures or skeletal myopathy. Serum creatine kinase levels were normal in family members with mutations of the lamin rod but mildly elevated in some family members with a defect in the tail domain of lamin C. Conclusions: Genetic defects in distinct domains of the nuclear-envelope proteins lamin A and lamin C selectively cause dilated cardiomyopathy with conduction-system disease or autosomal dominant Emery–Dreifuss muscular dystrophy. Missense mutations in the rod domain of the lamin A/C gene provide a genetic cause for dilated cardiomyopathy and indicate that this intermediate filament protein has an important role in cardiac conduction and contractility. (N Engl J Med 1999;341:1715-24.) [ABSTRACT FROM AUTHOR]

This article presents a letter to the editor regarding familial atrial fibrillation, as reported in the March 27, 2007, issue.

In the article, the authors examine the need to accelerate information technology (IT) innovations in the health sector as of September 2016. Also cited are the perceived factors that restrict innovation in the sector like technical integration issues and regulations that limit the flow of data to protect patient privacy, and some recommended strategies like the introduction of continuous innovation programs that foster long-term collaboration between developers and users.

A letter to the editor is presented in response to an article in the May 8, 2003 issue about a genotype-based risk-stratification algorithm for the long-QT syndrome.