Discussion
Cardiovascular operators have not yet reached a definitive consensus
regarding the best treatment strategy in the presence of co-existing
coronary artery and/or valve disease and extra-cranial carotid lesions
amenable of operative repair.2 During the last decade
there have not been systematic high-level evidence published, and two
randomized clinical trials failed to establish which should be the
recommended treatment strategy due to lack of adequate power and/or
because of slow enrollment.3-16 Still a pending matter
of debate, we believe that the choice to perform a single stage
intervention may still be reasonable based on our institutional
experience, especially in the presence of a homogeneous treatment
protocol among the centers involved.10 The 3.9%
postoperative mortality rate at 30-days observed in our cohort is
acceptable considering the magnitude of intervention and the high-risk
profile of the cohort: it is in line with the mean 5.1% in-hospital
mortality reported in the larger cohort of the National Inpatient Sample
analysis of isolated coronary artery bypass grafting, as well as not
significantly inferior to the 3.8% reported for the staged treatment of
the concomitant diseases.7,8,18-20
One modality for optimizing risk assessment is to use a predictive score
but, currently, there are no mortality predictive scoring systems for
single stage CVS and CEA.8,14,21,22 The predictors
identified in our series are reliable since they have been associated
with mortality in other experiences. When it comes to the carotid
revascularization component of this complex clinical scenario, the risk
of neurologic complications has been correlated to the clinical
relevance of the carotid stenosis, namely a history of
stroke.15,22,23 While there is no unquestionable
evidence that the majority of patients undergoing coronary artery bypass
grafting may benefit from CEA, high-grade extra-cranial carotid artery
stenosis poses a higher risk of stroke than patients without carotid
disease.1,2,23 The fact that stroke rate was lowest at
1.9% in the staged group of the vast cohort of the National Inpatient
Sample may support this observation. Furthermore, most of the strokes
have been mechanistically unrelated to pre-existing carotid artery
occlusive disease.1,2,18 For the sake of
comparability, the 1.3% rate found in our experience is favorable in
comparison with the 2.8% reported in a recent meta-analysis by Ursoet al .24 in patients undergoing isolated
coronary artery bypass grafting, and like the 2.5% in those undergoing
isolated percutaneous coronary intervention with drug-eluting stents.
Also, in our experience we did not observe a difference in occurrence of
new strokes between patients who had symptomatic or asymptomatic carotid
lesions. Taking into consideration that the recent clinical practice
guidelines of the European Society for Vascular Surgery (ESVS) reported
that CEA should be considered in patients with a history of stroke, and
considering the favorable data in our cohort, we consider single stage
CVS and CEA safe and effective in selected high-risk
patients.10
Considering that outcomes in patients undergoing carotid artery stenting
(CAS) markedly improved in recent years, CAS has been proposed as an
alternative strategy for carotid lesions, as transcatheter aortic valve
implantation for valve disease. In the cohort of the National Inpatient
Sample, the staged approach with CAS preceding coronary-artery bypass
grafting showed the lowest risk of mortality. However, CAS was
associated with highest risk of stroke, and a higher risk of stroke and
higher interstage risk of myocardial infarction for a total number of
staged CAS-first strategy that was twenty times fewer than single stage
coronary-artery bypass grafting and CEA.4 Thus, in
these patients with concomitant diseases there is minimal reasonable
evidence to widely support a CAS-first strategy.7,9,11