To study the inheritance of idiopathic dilated cardiomyopathy, we investigated a large kindred in which 11 young male members had definite or possible evidence of the disorder. The five affected males for whom we had complete clinical data survived for 5 to 12 months after the onset of symptoms, which occurred early in life (ages 15 to 21 years). In six other males, clinical data were incomplete but suggested possible cardiomyopathy. Three mothers of affected males were given a diagnosis of definite, and two of possible, late-onset dilated cardiomyopathy. These women presented in their 40s with atypical chest pain, and progressive congestive heart failure developed gradually over a period of 10 or more years. X-linked inheritance of dilated cardiomyopathy is suggested in this family by the early onset in males, late onset in females, and no evidence of male-to-male transmission. The late onset of the disease in females, in contrast to the early onset in hemizygous males, is compatible with heterozygosity for the mutant allele. Since most cases of genetically lethal X-linked syndromes appear to be sporadic, for every case of "idiopathic" dilated cardiomyopathy in which X-linked inheritance can be confirmed from family information, it is possible that there are several nonfamilial cases due to a mutation at the same locus.

Osteogenesis imperfecta (OI) is a rare inheritable disorder of connective tissue. While musculoskeletal abnormalities are well known, cardiovascular involvement is rare. Aortic root dilation is the most common cardiovascular manifestation. OI preferentially affects the left-sided heart valves, for unclear reasons, leading to aortic and mitral regurgitation. Valve replacement surgery carries a unique set of issues in this population, and fewer than 40 cases have been reported. We report a case of chronic severe aortic regurgitation in a patient with OI complicated by the development of a flail aortic valve leaflet and presenting with a transient ischemic attack. The patient subsequently underwent successful combined bioprosthetic aortic valve replacement and coronary artery bypass grafting. We review the literature on valvular disease and other cardiovascular manifestations in OI and the related surgical considerations relevant to this patient population.

To determine the constancy of hemodynamic and antianginal effects of the constant infusion of intravenous nitroglycerin (NTG) and their relationship to infusion rate and plasma NTG concentration, we administered maximal tolerated doses of intravenous NTG (range 10 to 120 ,g/min, mean = 52 + 33 ,ug/min) and placebo to 10 patients with chronic stable angina for 25 hr each in a randomized, double-blind fashion. Sublingual NTG (0.4 mg) was given at 24.5 hr of infusion as a positive control. Bicycle exercise time (NIH protocol), blood pressure, heart rate, exercise ST response, and venous plasma NTG were determined before and at 1, 4, 8, 24, and with widely varying slopes and intercepts. Intravenous NTG produced a sustained reduction in blood pressure and a rise in heart rate at rest, and a reduction in blood pressure during submaximal exercise at as late as 24 hr, associated with reduced submaximal ST segment abnormality. In contrast, exercise tolerance to onset of angina showed a marked initial increase on intravenous NTG but fell progressively and did not differ from that with placebo at 24 hr. Increased exercise tolerance was associated with an increase in maximal heart rate and double product (heart rate X blood pressure), suggesting that direct coronary vasodilation and/or reduced left ventricular volume were the principal determinants of increased exercise tolerance. The rates of fall in exercise tolerance over time varied widely among patients. Sublingual NTG produced a marked increase in exercise tolerance after a 24.5 hr placebo infusion, but not after intravenous NTG, despite similar exercise tolerance on intravenous NTG and placebo at 24 hr. The plasma NTG concentrations achieved with intravenous NTG were at least twice those reported for the peak sublingual NTG effect and up to 50 times those reported for 5 mg/24 hr release NTG patches. Thus, constant NTG infusion can result in constant high plasma NTG, but the initial marked increase in exercise tolerance diminishes progressively over 24 hr, as previously observed with NTG patches, consistent with development of tolerance. After prolonged high plasma NTG concentrations, the effect of sublingual NTG on exercise tolerance can be abolished. We conclude that rapid attenuation of antianginal effects during exercise is an inherent result of the continuous administration of NTG. It remains uncertain whether similar tolerance limits the efficacy of intravenous NTG in patients with cardiac ischemia at rest. Circulation 77, No. 6, 1376-1384, 1988 have shown marked attenuation of NTG patch effect over 24 hr, and little or no effect during long-term

In the light of technologic advances and the development of new imaging planes, the feasibility of two-dimensional echocardiographic visualization of coronary artery anatomy was reevaluated in the adult. Thirty-five subjects were studied using an ultrasonograph equipped with a 3.5 and 5.0 MHz annular array transducer, digital processing and cine loop review. There were 18 normal subjects and 17 patients with heart disease, including 9 patients with valvular, 5 patients with coronary, 2 patients with congenital and 1 patient with cardiomyopathic disease. The mean age was 47 +/- 18 years (range 17 to 79). Modifications of standard parasternal and apical views permitted high quality images of portions of each of the major epicardial vessels adequate for assessment of luminal diameter. The left main coronary artery was seen in 30 (86%) of the 35 subjects and its bifurcation was seen in 15. The left anterior descending coronary artery was seen in 30 subjects (mean length 3.9 +/- 2.3 cm, maximal length 7.5), the left circumflex artery in 11 (1.1 +/- 1.0, maximal 3.0) and the right coronary artery in 32 (5.6 +/- 2.6, maximal 12). Proximal and mid portions of the left anterior descending artery were seen in 23 and 11 subjects, respectively. The average proximal length visualized was 4.2 cm, and the average luminal diameter visualized was 4.9 mm. The average length of the mid left anterior descending coronary artery seen was 1.9 cm and the average luminal diameter seen was 4.6 mm. The proximal right coronary artery was seen in 17 subjects (average visualized length 2.7 cm and average diameter 3.1 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

To examine left ventricular function in mitral regurgitation (MR), we compared the ejection phase indexes of left ventricular contractility with maximal systolic elastance (Emax)