Familial myocardial disease with and without obstruction to left ventricular outflow. Clinical, hemodynamic, and angiographic findings

Dominantly inherited dilated cardiomyopathy

We describe a family in which there is segregating an autosomal dominant gene determining a cardiomyopathy. The pathodynamics is that of pump failure associated with dilatation of the heart, generally having an overt clinical onset from the fourth through seventh decades. Dysrhythmia is a frequent concomitant feature. There may be an associated skeletal myopathy, either producing a very mild proximal weakness or proving detectable only upon biopsy. This family is similar to other reported cases of familial dominant "idiopathic" dilated cardiomyopathy, but the nature of the heterogeneity within this category remains to be elucidated. The roles of echocardiography, cardiac biopsy, and skeletal muscle biopsy in the presymptomatic detection of the heterozygote are noted.

Human lymphocyte antigens in hypertrophic cardiomyopathy

An increasing number of genetic studies in hypertrophic cardiomyopathy challenge conventional views on inheritance and suggest genetic heterogeneity or non-genetic disease. We have found changes in relative risk for some antigens with significantly increased frequency of HLA antigen DR4 in this condition. These findings are consistent with there being a genetic component in susceptibility to hypertrophic cardiomyopathy. No evidence was found for HLA linkage using either sib pair analysis or lod scores. This suggests that hypertrophic cardiomyopathy does not have a disease susceptibility gene related to the HLA region on the short arm of chromosome number six. Population HLA associations with hypertrophic cardiomyopathy must thus be explained by other influences of the genetic background on disease susceptibility.

Prenatal ultrasonic diagnosis of familial asymmetric septal hypertrophy

Hypertrophic cardiomyopathy usually manifests clinically in the second or third decade of life. Two dimensional echocardiography is a reliable indicator of the presence of the disease. This technique is of use in the screening of fetuses at risk for familial cardiomyopathy. This report describes the prenatal echocardiographic detection of hypertrophic cardiomyopathy in the fetus of a mother with hypertrophic cardiomyopathy localized to the apical region of the left ventricle.

Patterns of inheritance in hypertrophic cardiomyopathy: assessment by M-mode and two-dimensional echocardiography

To determine the mode of inheritance of hypertrophic cardiomyopathy (HC), 367 relatives from 70 families with HC were studied by M-mode and 2-dimensional echocardiography (2-D echo). Inspection of individual family pedigrees suggested that HC was genetically transmitted in 39 pedigrees (56%) and probably sporadic in 31 (44%). Of the 39 pedigrees with familial occurrence, 30 had patterns of inheritance that were most consistent with autosomal dominant transmission. A complex mathematical pedigree analysis determined that patterns of genetic transmission observed in the overall study group were not consistent with known models of autosomal dominant, autosomal recessive, or X-linked inheritance and did not support a unified concept of single-gene Mendelian transmission for all families. The proportion of first-degree relatives affected by HC was 22%, with HC most common in fathers of the proband and least common in offspring. About 20% of the affected relatives (10 of 53) appeared to have inherited a "subclinical" form of HC, in which the sole evidence of HC was the morphologic expression detectable only with echocardiography. Probands and affected relatives differed distinctly with regard to the expression of HC. Probands most often showed functional limitation (81%), subaortic obstruction at rest (53%), particularly diffuse distribution of left ventricular hypertrophy (59%) and marked septal thickening (mean 23 mm). In contrast, affected relatives were characterized by absence of functional limitation (72%) and subaortic obstruction (94%), localized and unusual sites of hypertrophy (60%) and only modest septal thickening (mean 17 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Two forms of hypertrophic cardiomyopathy distinguished by inheritance of HLA haplotypes and left ventricular outflow tract obstruction

In this study we have performed human leukocyte antigen (HLA)-A and B typing on nine patients with hypertrophic cardiomyopathy (HCM) and their relatives. Four patients had relatives who also had the disease. HLA typing of the familial form of HCM revealed a very close association of a given HLA-A,B haplotype with the occurrence of the disease. All four patients who had affected relatives had obstruction of left ventricular outflow (LVOT), while four patients with unaffected relatives did not have obstruction. One additional patient with obstruction and without familial incidence was an only child and had few living relatives. Thus, HCM can be divided into two subtypes: a familial form linked to the HLA-A,B system, which may be related to obstructive type, and a sporadic form not linked to HLA antigens. These data confirm the existence of at least two separate forms of hypertrophic cardiomyopathy. The study also confirms their existence in the Japanese population, with a completely different gene pool than the population from the southeastern United States in whom the observation was initially described.

Hypertrophic cardiomyopathy and human leukocyte antigen linkage: differentiation of two forms of hypertrophic cardiomyopathy

To determine whether hypertrophic cardiomyopathy is associated with a human leukocyte antigen (HLA) phenotype, we tissue-typed 70 unrelated afflicted patients and 86 of their asymptomatic family members (from nine separate kindreds). Forty-five per cent of the white patients had B-12 antigen as compared to 23 per cent in matched control subjects; 69 per cent of black patients had a B-5-complex antigen as compared to 33 per cent in matched controls. Patients with a B-12 or B-5-complex antigen were nonhypertensive and had family members with the disease. Patients without these antigens were severely hypertensive and had no affected family members. Linkage analysis of six families revealed a lod score of 7.7 for asymmetric septal hypertrophy and the HLA region of chromosome 6. We conclude that there is a heritable, nonhypertensive form of hypertrophic cardiomyopathy linked to the HLA loci on chromosome 6 and that a sporadic form is associated with severe, systemic hypertension.

Asymmetric septal hypertrophy in a large amish kindred

We report a large Amish kindred in which asymmetric septal hypertrophy (ASH) appeared to segregate as an autosomal dominant gene. This kindred was ascertained through a 3-month-old infant and her father. The striking differences between father and daughter regarding clinical presentation and course exemplify the variable expressivity of this condition. The importance of genetic factors in diagnosis and counseling are discussed. Previous reports of ASH in infants and children are reviewed.

Hypertrophic cardiomyopathy with unusual features in a family

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Hypertrophic cardiomyopathy

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