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H U Sauer

Publications and source records attributed to H U Sauer.

2 recordsLinked to original sources

[Coronary fistulas--high prevalence in patients with heart transplantation].

Coronary artery fistulas have recently been reported to occur frequently in patients after heart transplantation due to repeated endomyocardial biopsies. To investigate if there is a relationship between development of coronary artery fistulas and the number of biopsies performed in transplanted patients, we studied the prevalence and localization of coronary artery fistulas in 168 patients after heart transplantation and in 100 control subjects. In addition to biplane ventriculography of the left ventricle, and in two-thirds of the patients the right ventricle as well, coronary angiography in multiple projections was performed at yearly intervals. The angiographic criterion for a coronary fistula was specified as visualization of a direct confluence from the arterial vascular lumen into a cardiac chamber, independent of size, which occurred prior to the venous phase, documented by opacification of the coronary sinus or great cardiac vein. The size of the fistula was assessed semi-quantitatively into one of three categories as small, barely detectable flow from a small arterial vessel with opacification of less than 10% of the involved chamber, large with direct flow from a large branch with opacification of more than one-third of the involved chamber (Figures 1a to 1c). Endomyocardial biopsies were performed weekly for the first three months after transplantation, thereafter, the interval was increased one week every three months. The prevalence of coronary fistulas in patients after heart transplantation was higher at 135/168 than in control subjects at 43/100. There were also more fistulas per patient (1.8 vs 0.67) in those transplanted than in control subjects (Figures 2a and 2b).(ABSTRACT TRUNCATED AT 250 WORDS)

Arteriovenous Fistula

[Directional atherectomy--current status].

To deal with the problem of restenosis after PTCA, several new methods and devices for treating atheromatous lesions have been developed. Among the promising techniques, is the opportunity to remove atheromatous material with the directional coronary atherectomy catheter designed by J.B. Simpson. The atherectomy catheter consists of a housing at the catheter tip with a concave cutting device which is rotated at a speed of 2000 r.p.m. The housing is positioned at the stenosis by means of a central guidewire; the material to be removed protrudes into the housing. With an inflatable balloon on the opposite side, the position of the housing is fixed in the coronary artery, the plaque is pressed further into the orifice and severed by the rotating blade. The material removed remains in the tip of the housing and can be used for morphologic examination as well as for functional studies with individual cell cultures. Experience published to date encompasses the results of 1032 treated stenoses. The majority of the treated lesions, 53%, were localized in the left anterior descending coronary artery; in 22% the lesion were located in the right coronary artery, in 17% in an aorto-coronary venous bypass graft. Due to the difficulty in positioning the relatively rigid atherectomy catheter, the method has only been employed in the circumflex artery in 6%. In a substantial number of patients, the stenoses had already been subjected to PTCA; in 57% of 963 patients treated with atherectomy, angioplasty had been performed previously, in 25% bypass grafting had been carried out. The primary success rate was 93%.(ABSTRACT TRUNCATED AT 250 WORDS)

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