First impressions are good, but appearances can be deceptive!

Zahn et al. publish the latest analyses from the Carotid Artery Stent (CAS) Registry of the Arbeitsgemeinschaft Leitende Kardiologische Krankenhausartzte (ALKK) of Germany. This reports outcomes following CAS in octogenarians (n 1⁄4 321) compared with younger patients (n 1⁄4 2557). As indicated in the introduction, this analysis was prompted by conflicting published data regarding the safety of CAS in elderly patients. Having reviewed their experience, the authors conclude that ‘the in-hospital stroke or death rate does increase significantly with older age; however, there was no excess complication rate in octogenarians’. Is this conclusion valid and how should the ALKK findings influence practice? Notwithstanding the marked disparity in numbers between the two groups, the ALKK Registry make a number of important observations in patients aged .80 years undergoing CAS. (i)The case volume (proportional to the total annual workload) is increasing rapidly (6% in 1996 vs. 14% in 2005). (ii) CAS took longer to perform (45 vs. 40 min, P 1⁄4 0.008). (iii) CAS was associated with a higher incidence of residual stenosis at the end of the procedure (10 vs. 5%, P 1⁄4 0.006). (iv) CAS was more frequently aborted in patients aged .80 years (7 vs. 2%, P , 0.001). (v) Elderly patients were less likely to undergo CAS while receiving statin therapy (71 vs. 84%, P , 0.001). (vi) Elderly CAS patients faced no excess risk of access complications (2.5 vs. 1.3%, P 1⁄4 0.13). (vii) Octogenarian CAS patients did face a significantly higher in-hospital death/stroke rate (5.5 vs. 3.2% P 1⁄4 0.032). (viii) Not surprisingly, octogenarian CAS patients encountered a significantly higher in-hospital rate of death/stroke and TIA (11 vs. 6%, P 1⁄4 0.003). These findings will, of course, be open to individual interpretation. However, to this reader, observations (ii)–(iv) are interesting but probably unimportant; (v) is worrying, because it suggests sub-optimal medical therapy (a criticism common to many cardiovascular studies), whereas (vi) is reassuring. Observation (i) is only clinically important if the indications for intervening on patients aged .80 years are inappropriate, while everyone accepts that the inclusion of TIA within a ’hard’ peri-operative endpoint is unnecessary. Like its counterpart carotid endarterectomy (CEA), the rationale underlying CAS is that it is performed to prevent stroke. If randomized trials showed that the only difference in peri-operative risk was a higher incidence of TIA with CAS, then CEA would (almost certainly) become the ’silver’ standard overnight. Accordingly, the ’real meat’ of the debate is observations (i) and (vii). Fundamental to interpretation of observations (i) and (vii) is that the reader not only considers what the ALKK Registry has said, but more importantly what it has not said! Let us start with a simple question; ‘why do we treat octogenarian patients with severe carotid disease?’ The answer should be that these patients are (i) at higher risk of suffering a stroke if CAS/CEA is withheld and (ii) the procedural risks of CEA/ CAS are not so high that long-term stroke prevention is compromised. The answer cannot simply be that, ‘intervention is justified in symptomatic and asymptomatic patients over 80, the only debate being whether CAS is preferable to CEA!’. First, consider the symptomatic patient. Since the landmark trials published, we now have more evidence to guide practice than ever before. Symptomatic patients face a significantly higher risk of stroke than their asymptomatic counterparts. However, within this ‘recently symptomatic’ cohort, we know that several clinical and imaging features mark out those who gain greatly increased benefit from intervention provided the procedural risks are ,8%. These include male gender, hemispheric symptoms, recurring symptoms for .6 months, very recent symptoms (within one month), CEA performed within 4 weeks of the most recent event, contralateral occlusion, increasingly severe stenosis (but not near occlusion), plaque irregularity, tandem intracranial disease, failure to recruit intracranial collaterals, and patients aged .75 years. Previously, many clinicians thought that elderly, symptomatic patients gained little long-term benefit from CEA because it was assumed that the procedural risks would be The opinions expressed in this article are not necessarily those of the Editors of the European Heart Journal or of the European Society of Cardiology.