Fibrillar collagens I and III, nonfibrillar collagen IV, and the glycoproteins fibronectin and laminin, are elements of the myocardial extracellular matrix (ECM). Alterations in the normal concentrations and ratios of these elements may reflect remodeling in response to physiologic stress. In the case of patients' post-heart transplantation (HTx), specific patterns of alteration may herald myocardial dysfunction. Right ventricular biopsies were taken from the same 28 HTx patients before implantation and 1 week, 2 weeks, and 1, 2, and 3 years after HTx. The above-noted five ECM proteins, six matrix metalloproteinases (MMPs) and two of their tissue inhibitors (TIMPs) were detected by immunohistochemistry and scored as cells per square millimeter or semiquantitatively. The total connective tissue fibers were detected by connective tissue stain and morphometry. Variations in these ECM components were followed in the same patient cohort over 3 years. In summary, during the first 2 weeks after HTx, a predominant increase in connective tissue occurred. Increases in MMP-8 and MMP-9 were found. By 3 years after transplantation, there was a decrease of connective tissue fibers and a significant reduction of all ECM components and an increase in MMPs and TIMPs. These findings may reflect a pattern of remodeling specific to the transplanted heart.
Of 22 patients with the classical clinical signs of pulmonary oedema (orthopnoe, cyanosis, sweating and rales heard at a distance) 15 (Group A) were observed clinically, while seven (Group B) underwent haemodynamic studies. Those in Group A were given 0.8-2.4 mg nitroglycerin sublingually one to six times at 5--10 minute intervals. Within five minutes of nitroglycerin administration 7 of the 15 had their first signs of clinical improvement. In 11 patients the rales had disappeared after 15--20 minutes or had regressed. In the remainder the dyspnoea had decreased so that at this point in 14 of the 15 patients various degrees of improvement had occurred. Four patients were completely without clinical signs after 30 minutes. The increased arterial blood pressure and heart rate had fallen markedly. In the seven patients of Group B mean left ventricular filling pressure fell within ten minutes of nitroglycerin administration (1.6 mg) from 33 +/- 10 to 24 +/- 8 mmHg, cardiac output rising sifnificantly from 3.3 +/- 0.8 to 3.7 +/- 0.8 1/min. Such favourable results with nitroglycerin are to be expected only if the pulmonary oedema is of cardiac origin.
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