Coronary stenting in small vessels: reply

Pierfrancesco Agostoni

Interventional Cardiology Unit
S. Raffaele Hospital
"Vita e Salute" University
University of Milan
Via Olgettina
60 20132 Milan, Italy
Tel.: +39-349-4303888
Fax: +39-(0)45-914727
E-mail address: agostonipf{at}genie.it

Giuseppe G.L. Biondi-Zoccai

Interventional Cardiology Unit
S. Raffaele Hospital
"Vita e Salute" University
University of Milan

Gabriele L. Gasparini

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona, Italy

Maurizio Anselmi

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona, Italy

Giorgio Morando

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona, Italy

Marco Turri

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona, Italy

Antonio Abbate

Department of Medicine
Virginia Commonwealth University
Medical College of Virginia Campus
Richmond
VA, USA

Eugene P. McFadden

Thoraxcenter
Erasmus MC
Rotterdam,
The Netherlands

Corrado Vassanelli

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona, Italy

Piero Zardini

Department of Biomedical and Surgical
Sciences
Section of Cardiology
University of Verona
Verona
Italy

Antonio Colombo

Interventional Cardiology Unit
S. Raffaele Hospital
"Vita e Salute" University
University of Milan

Patrick W. Serruys

Thoraxcenter
Erasmus MC
Rotterdam,
The Netherlands

We deeply appreciate the interest of Moreno et al. on our meta-analysis and we welcome the continuous debate regarding this issue. Unfortunately, we partially disagree with Moreno et al. on their response1 to our previous letter2 to the editor published in the Journal of the American College of Cardiology, and on their present criticisms.

In particular, concerning their previous reply letter in the Journal of the American College of Cardiology,1 we believe that they did not sufficiently evaluate the importance of statistical heterogeneity among trials, present both in our and their meta-analyses. Although a quantitative estimate may be obtained also in the case of statistical heterogeneity, using the random effect model, further analyses should be utilized to better investigate this heterogeneity and its possible value. Indeed, in all the meta-analyses we published, we always performed prehoc or posthoc subgroup analyses in order to confirm whether the main result was sufficiently robust to be maintained in the subgroups or if there were different trends, related to some other variables, that could explain the presence of heterogeneity. In addition, meta-regression, attempted by Moreno et al.1 should be performed based on standard methods, as clearly explained in Biondi-Zoccai et al.3 Next, the trial by Kinsara et al.,4 included in our meta-analysis, should have also been included in their meta-analysis, as long as it was published as an abstract in 1999.5

Regarding their present criticisms, first, we believe that, as a meta-analysis may be considered an original investigation, it should have its own primary endpoint which need not necessarily be the same as the one present in the trials included in the systematic review. Indeed, the major strength of a meta-analysis comes from the higher power (because of the larger sample size) to detect differences in outcomes that could not be adequately investigated by single trials.5,6 In addition, our predefined criterion for optimal balloon angioplasty (diameter stenosis <20%), although arbitrary as correctly stated by Moreno et al., in their current letter, came from previous suggestions and analyses done by experts (as we stated in our methods section) and it was a predefined form of subgroup analysis to assess whether the main result was also maintained in the subgroups, or there were different trends, as previously explained. Indeed, we also performed other subgroup analyses, but they were all burdened by significant heterogeneity. Moreover, the references 4 and 5 used by Moreno et al. in their current letter refer to two studies performed in coronary vessels with a large range of vessel size and not only small ones, thus the cut-off of 35% after angioplasty as residual stenosis indicating suboptimal result may not correctly apply to small vessels. Finally, in our opinion, the intention-to-treat analysis (including cross-over from balloon angioplasty to stent, considered in each trial as bail-out and not provisional) was the best approach as we did not want to simply compare stenting with balloon, but we would like to understand why there were different results in trials with similar design and whether the possible benefit of routine stenting was real or could be balanced by a strategy of provisional stenting.

The real value of a meta-analysis relies on the correct selection of data and also on the right statistical methods used.6,7 The best approach to reconcile Moreno's and our work would be an individual patient data meta-analysis, scientifically intriguing, but logistically and economically demanding.7

References

  1. Moreno R, Fernandez C, Macaya C. Coronary stenting in small vessels. Reply. J Am Coll Cardiol 2005;45:324–325.[Free Full Text]
  2. Agostoni P, Biondi-Zoccai GG, Abbate A. Coronary stenting in small vessels. Letter to the Editor. J Am Coll Cardiol 2005;45:323–324.[Free Full Text]
  3. Biondi-Zoccai GG, Abbate A, Agostoni P, Testa L, Burzotta F, Lotrionte M, Trani C, Biasucci LM. Long-term benefits of an early invasive management in acute coronary syndromes depend on intracoronary stenting and aggressive antiplatelet treatment: a metaregression. Am Heart J 2005;149:504–511.[CrossRef][ISI][Medline]
  4. Kinsara AJ, Niazi K, Patel I, Amoudi O. Effectiveness of stents in small coronary arteries. Am J Cardiol 2003;92:584–587.[CrossRef][ISI][Medline]
  5. Niazi K. Stents in small coronary vessels: a prospective, randomized study (Abstract). Circulation 1999; (Suppl. I):1–510.
  6. Biondi-Zoccai GG, Testa L, Agostoni P. A practical algorithm for systematic reviews in cardiovascular medicine. Ital Heart J 2004;5:486–487.[Medline]
  7. Biondi-Zoccai GG, Agostoni P, Abbate A. Parallel hierarchy of scientific studies in cardiovascular medicine. Ital Heart J 2003;4:819–820.




This Article
Full Text (PDF)
All Versions of this Article:
26/15/1562-a    most recent
ehi345v1
Alert me when this article is cited
Alert me if a correction is posted
Services
Email this article to a friend
Similar articles in this journal
Similar articles in ISI Web of Science
Similar articles in PubMed
Alert me to new issues of the journal
Add to My Personal Archive
Download to citation manager
Request Permissions
Google Scholar
Articles by Agostoni, P.
Articles by Serruys, P. W.
PubMed
PubMed Citation
Articles by Agostoni, P.
Articles by Serruys, P. W.