Success of Revascularization Vs Clinical Outcomes
If the mechanism of cardiac event-free and overall survival with CABG is due to revascularization, then the technical success in achieving revascularization should predict the clinical outcomes. Studies purporting to show a significant relationship between completeness of revascularization and symptomatic outcomes and survival have several methodologic problems. These include:
Few patients;
Variable definitions of revascularization[28];
Using exercise tolerance as the end point without documenting the extent of exercise rehabilitation post surgery[29]; and
Defining complete vs incomplete revascularization by follow-up angiograms taken 2-12 months after the CABG.[30]
Jones and colleagues[31] reported an 8% survival advantage with complete revascularization compared with incomplete revascularization at 8 years. However, at entry into the study, the incompletely revascularized patients had a greater percentage of 3-vessel disease (P < .001), more previous AMIs (P < .001), and lower ejection fractions (P < .001).
The CASS registry involved more patients with 3-vessel CAD who received CABG than all of the other studies combined (n = 3372) and followed them for cardiac-event-free and overall survival. This study demonstrated no difference in survival or cardiac-event-free survival at 6 years related to the success of revascularization.[32]
In the Bypass Angioplasty Revascularization Investigation (BARI), which randomized patients with multivessel disease to CABG or angioplasty, the practice of intended incomplete revascularization in the angioplasty group did not result in a lower mortality.[33]
© 2002 Medscape
Cite this: Coronary Artery Bypass Grafting (CABG): Reassessing Efficacy, Safety, and Cost - Medscape - Jun 19, 2002.
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