The New England Journal of Medicine
The authors reply:To the Editor: Clinical evaluation of the patients was routinely carried out in the outpatient clinic by physicians not directly involved in the study. Furthermore, quantitative analysis of the vessels was performed by two observers who were not involved in the study and were blinded to its aims.The size of the balloons and the inflation pressures used in our study were chosen to achieve a balloon:artery ratio close to 1:1, which is considered to be the ideal ratio for coronary angioplasty. 1 The diameter of the balloon should be chosen carefully; undersizing (balloon:artery ratio, Ͻ0.9) can result in substantial residual stenosis, whereas oversizing (balloon:artery ratio, у1.2) increases the risk of dissection and acute complications.1 In our study, the balloon:artery ratio was 0.97, which is quite close to the ideal size (this ratio can be derived from the data in Tables 1 and 3 of our article). Conversely, the use of PalmazSchatz stents requires a higher inflation pressure, and balloon oversizing is needed to achieve optimal expansion of the stent. Finally, we would like to emphasize that our prospective study shows a clear superiority of stenting over balloon angioplasty in terms of both the event rate and the restenosis rate in a well-selected and homogeneous group of patients (i.e., those with an isolated proximal stenosis of the left anterior descending coronary artery). In contrast, the two largest randomized, multicenter studies comparing stenting with coronary angioplasty 2,3 enrolled patients who were heterogeneous with regard to both the location of coronary stenoses and the number of diseased vessels, resulting in confounding of the findings. Indeed, in one of the studies, 2 the actuarial rate of late event-free survival did not differ statistically between patients treated with angioplasty and those treated with stenting, although the latter group had a larger luminal diameter at follow-up. In the other study, 3 patients who underwent stent implantation had a better actuarial rate of late event-free survival than those treated with angioplasty, although the luminal diameter at follow-up did not differ statistically between the two groups.
Disorders of the Autonomic Nervous SystemTo the Editor: In October 1995, a committee composed of members of the American Autonomic Society and members of the American Academy of Neurology met to develop consensus definitions of multiple-system atrophy (the Shy-Drager syndrome) and pure autonomic failure (idiopathic orthostatic hypotension, progressive autonomic failure, and the Bradbury-Eggleston syndrome). The previous nosologic classification, particularly the use of the term Shy-Drager syndrome, was misleading and did not reflect current knowledge about autonomic disorders. Although the scheme presented was not perfect, it is consistent with present information about these varied, complicated conditions.
1,2Goldstein et al. (March 6 issue) 3 propose a new classification of autonomic disorders based on ...
