Author + information
- Received May 27, 2016
- Revision received August 2, 2016
- Accepted August 11, 2016
- Published online October 24, 2016.
- S1936879816313164-d05e8da58143050af01c47226873293eNicolas Debry, MDa,
- S1936879816313164-6e1496561989791cc644e044d6cb2b0bCédric Delhaye, MDa,
- S1936879816313164-e12a3382cf3a92c7afde42737b5ff3beAlexandre Azmoun, MDb,
- S1936879816313164-9f6a4e2a6acc2572d0a7f26d15bd1d67Ramzi Ramadan, MDb,
- S1936879816313164-94a601fbb4ebf1a5a3086e28257478e1Sahbi Fradi, MDb,
- S1936879816313164-f7ddc8ecc96e36173b4834c8c69fb345Philippe Brenot, MDb,
- S1936879816313164-8de0ae2d6efdb9bda4c74e1f7be8c987Arnaud Sudre, MDa,
- S1936879816313164-4b2779b5f63c163894448f804e42259cMouhamed Djahoum Moussa, MDa,
- S1936879816313164-1d89a3a268baebf88bf7199a2278dc1fDidier Tchetche, MDc,
- S1936879816313164-8253f294a5af5a5403d155591c420106Said Ghostine, MDb,
- S1936879816313164-dc94e6e86982a722efaf58282ff097e1Darren Mylotte, MDd and
- S1936879816313164-fda91c7007aa45cb0efa898292e3539cThomas Modine, MD, PhDa,∗ ()
- aHeart Team, Cardiology and Cardiovascular Surgery Departments, Institut Cardiopulmonaire, CHRU Lille, Lille, France
- bHeart Team, Cardiology and Cardiovascular Surgery Departments, Centre Médico-Chirurgical Marie Lannelongue (CCML), Le Plessis-Robinson, France
- cClinique Pasteur, Toulouse, France
- dGalway University Hospitals, Galway, Ireland
- ↵∗Reprint requests and correspondence:
Dr. Thomas Modine, Boulevard du Professeur Jules Leclercq, Hôpital Cardiologique, CHRU Lille, Lille 59000, France.
Objectives The study sought to assess the safety and efficacy of a minimally invasive strategy (MIS) (local anesthesia and conscious sedation) compared to general anesthesia (GA) among the largest published cohort of patients undergoing transcarotid transcatheter aortic valve replacement (TAVR).
Background Transcarotid TAVR has been shown to be feasible and safe. There is, however, no information pertaining to the mode anesthesia in these procedures.
Methods Between 2009 and 2014, 174 patients underwent transcarotid TAVR at 2 French centers. All patients were unsuitable for transfemoral TAVR due to severe peripheral vascular disease. An MIS was undertaken in 29.8% (n = 52) and GA in 70.1% (n = 122). One-year clinical outcomes were available in all patients and were described according to the Valve Academic Research Consortium-2 consensus.
Results Transcarotid vascular access and transcatheter valve deployment was successful in all cases. Thirty-day mortality was 7.4% (n = 13) and 1-year all-cause and cardiovascular mortality were 12.6% (n = 22) and 8.0% (n = 14), respectively. According to the type of anesthesia, there was no between group difference in 30-day mortality (GA 7.3% vs. MIS 7.6%; p = 0.94), 1-year mortality (GA 13.9% vs. MIS 9.6%; p = 0.43), 1-month clinical efficacy (GA 85.2% vs. MIS 94.2%; p = 0.09), and early safety (GA 77.8% vs. MIS 86.5%; p = 0.18). There were 10 (5.7%) periprocedural cerebrovascular events: 4 strokes (2.2%) and 6 transient ischemic attacks (3.4%) among those treated with GA. There was neither stroke nor transient ischemic attack in the MIS group (p < 0.001).
Conclusions The transcarotid approach for TAVR is feasible using general or local anesthesia. A higher rate of perioperative strokes was observed with GA.
- aortic stenosis
- general anesthesia
- local anesthesia
- transcarotid access
- transcatheter aortic valve replacement
Transcatheter aortic valve replacement (TAVR) is an alternative to conventional surgical aortic valve replacement for patients with symptomatic severe aortic valve stenosis at high operative risk (1). A transfemoral approach is the most commonly used vascular access for TAVR, however, many patients have concomitant peripheral vascular disease that may render this access impossible or at high risk of bleeding and vascular complications (2). We have previously described the technique of transcarotid vascular access for TAVR using either local or general anesthesia (GA) (3–5).
The use of anesthesia varies greatly during TAVR, with no clear consensus of the optimal strategy (6). Transfemoral TAVR with a minimally invasive strategy (MIS) (local anesthesia and conscious sedation) is the preferred strategy, and it has been associated with similar safety and efficacy to GA (7,8). There remain no comparative data for these strategies with the transcarotid approach.
The purpose of this study was to report early safety and efficacy for transcarotid TAVR managed with minimally invasive or GA strategies.
Between April 2009 and December 2014, consecutive patients undergoing transcarotid TAVR at 2 French institutions (Hôpital Cardiologique, CHRU Lille, Lille, France; Centre Médico-Chirurgical Marie Lannelongue CCML, Le Plessis-Robinson, France) were included in a dedicated prospective database (around 6% of total TAVR patients in these institutions). All patients had severe symptomatic aortic valve stenosis (indexed aortic valve area <0.6 cm2/m2) and multiple comorbidities. The institutional multidisciplinary heart teams agreed each patient should proceed to TAVR. In all cases, the transfemoral approach was precluded by severe peripheral arterial disease or prior iliofemoral intervention or surgery. Many patients also manifested relative contraindications to other alternate access routes for TAVR: subclavian access with patent internal thoracic arterial grafts, or transapical or direct aortic approach with respiratory dysfunction (9). All patients gave written informed consent for the procedures.
Suitable carotid artery anatomy was assessed with contrast angiography or more recently with pre-operative multislice computed tomography (MSCT). Patients with small caliber (≤6 mm), heavily calcified, severely tortuous, or stenotic iliofemoral anatomy, and those with significant descending aortic pathology were considered candidates for transcarotid TAVR. The dimensions of the carotid, subclavian, and vertebral arteries were carefully assessed using MSCT. Patients with significant (≥50%) common or internal carotid artery stenosis, plaque considered to be at high risk of embolization, or those with congenital variants of the aortic arch (e.g., Bovine arch) were not considered for transcarotid TAVR. A common carotid artery minimal luminal diameter threshold of ≥6.0 mm was consideration appropriate for transcarotid vascular access. Prior ipsilateral carotid artery intervention, contralateral carotid artery occlusion, or stenosis or occlusion of the vertebral arteries were also considered to be contraindications to transcarotid TAVR.
Cerebral magnetic resonance angiography (MRA) can accurately delineate the components of the circle of Willis and determine the adequacy of cerebral collateral blood flow (10). Screening cerebral MRA was performed and interpreted by neuroimaging specialists to evaluate collateral cerebral blood flow, and patients with suspected inadequate collateral flow were excluded. In cases with equivocal cerebral MRA, transcranial echo Doppler was used to further identify patients with the potential for cerebral hypoperfusion.
Procedures were performed in a hybrid operating theater by a multidisciplinary team including anesthesiologists, interventional cardiologists, and cardiac surgeons. Initially, the left common carotid artery was preferentially selected, as it afforded simpler cardiac catheterization and operating room configuration. With experience, however, the right side was chosen with increasing frequency. Selection of the bioprosthesis (Edwards SAPIEN [Edwards Lifesciences, Irvine, California], Medtronic CoreValve [Medtronic Inc., Minneapolis, Minnesota], Medtronic CoreValve Evolut R, or Boston Scientific Lotus Valve, [Boston Scientific, Marlborough, Massachusetts]) was determined following aortic root assessment using MSCT.
Standard transcarotid TAVR implantation technique was followed as previously described (4,11) (Figures 1 and 2). Procedures were performed using the same protocol and materials for both sides; however, the hybrid room setup was changed according to the access side. In selected cases, according to operator preference, a drain was placed at the carotid incision site. Prosthetic valve function was assessed by transthoracic echocardiography at the end of the procedure, post-operative day 1, prior to discharge, and at 30 days. Doppler imaging of the carotid artery was performed before discharge.
Intraoperatively, cerebral perfusion was continually monitored using cerebral oximetry with near infrared spectrometry (Equanox 7600, Nonnin Medical Inc., North Plymouth, Minnesota). Systolic blood pressure was maintained above 100 mm Hg throughout the procedure. Since 2009, the number of procedures managed using an MIS (local sedation and conscious sedation) has increased gradually. In these patients, the level of sedation was controlled after a transient carotid artery cross-clamping test for 3 min. This entailed assessment of consciousness and clinical neurological status during transient carotid artery cross-clamping. Transesophageal echocardiography was not used in these patients. Exposure of the right or left carotid artery was performed under local anesthesia with lidocaine and an infusion of remifentanil. Among those undergoing TAVR with GA, pre-medication, induction, and maintenance of anesthesia was performed using standard techniques. Intraoperative cerebral monitoring was performed to maintain a bispectral cerebral monitoring index between 40 and 50. Transesophageal echocardiography was used in GA these patients when required.
The primary endpoints of interest were 1-month early safety and 1-month clinical efficacy, as defined by the updated Valve Academic Research Consortium (VARC)-2 consensus (12). Secondary endpoints included all-cause and cardiovascular mortality at 1 year as well as stroke. The latter was of particular interest, and was defined according to VARC-2 consensus (12). Stroke diagnosis required input from a stroke physician or diagnostic neuroimaging. Nonfocal global encephalopathy was not defined as stroke without neuroimaging evidence of cerebral infarction (12). The duration of symptoms or the demonstration of an ischemic or hemorrhagic lesion on neuroimaging further defined stroke (≥24 h; positive imaging) or transient ischemic attack (TIA) (<24 h; negative imaging).
Results for continuous variables were expressed as mean ± SD when data were symmetrically distributed or, otherwise, as median (interquartile range). The normality of distribution was assessed using Shapiro-Wilk test and normality diagrams. Results for categorical variables were expressed as frequencies and percentages. Comparative analyses were obtained using the chi-square test for categorical data; when not applicable because of the sample size, Fisher’s exact test was used. For numerical variables, we used an analysis of variance test or Kruskal-Wallis test if normality of distribution was not present. Survival was graphically depicted using Kaplan-Meier curves and between-group differences were compared using the log-rank test. Cox proportional hazards regression analysis was used to determine independent predictors of 1-year mortality. Only unique variables with a p value <0.10 in univariable analysis were entered into the final multivariable model. We considered p values <0.05 statistically significant. Statistical analysis was performed using commercial software (SAS version 9.3, SAS Institute, Cary, North Carolina).
The baseline demographic, clinical, and echocardiographic characteristics of the study population are summarized in Table 1. The mean patient age was 80.5 ± 7.9 years and most 55.1% (n = 96) were men. The average Society of Thoracic Surgeons predicted risk of mortality score was 8.4 ± 4.6%. There were few differences between the MIS and GA groups: the MIS cohort had significantly more coronary artery disease (p < 0.001) and prior revascularization (p = 0.001).
GA (n = 122) was the predominant anesthetic approach used in the first years of the study (95% GA vs. 5% MIS). In 2011, we performed the first MIS procedure, and this strategy has become more common over time, with 70% of cases using GA and 30% using MIS by the final year. Two patients in the MIS group had loss of consciousness occurring during the initial carotid cross-clamping test. In both cases, removal of the clamp afforded complete recovery within a few seconds. To ensure cerebral perfusion during these procedures, passive antegrade carotid perfusion was achieved through a temporary femoro-carotid shunt. This was achieved by inserting an 8-F sheath into the ipsilateral femoral artery and connecting this to a carotid shunt (POLYSHUNT, Perouse Medical, Ivry-le-Temple, France), which was introduced in a more distal segment of the carotid artery after a small arteriotomy. In both cases, a second cross-clamping test yielded no change in neurological status. In total, 4 patients (7.6%) converted from MIS to GA, due to patient discomfort (n = 2), or respiratory distress (n = 2), and were classified in the MIS group. They did not have any cerebrovascular or adverse events. Conversion to surgical aortic valve replacement did not occur.
Successful carotid vascular access was achieved in all cases. We had no valve embolization. The implanted transcatheter valves were Medtronic CoreValve 79.8% (n = 139), Medtronic CoreValve Evolut R 2.2% (n = 4), Edwards SAPIEN 16.6% (XT n = 26, S3 n = 3), and Boston Scientific Lotus Valve 1.1% (n = 2). The distribution of valve types was similar between anesthesia groups, and device success was achieved in 88% and 93% of the MIS and GA patients, respectively (p = 0.26). Three patients (1.7%) required implantation of a second transcatheter valve during the index procedure due to low or high implantation. The series included 7 (4.0%) cases where a transcatheter valve was placed inside a failing aortic bioprosthesis.
In the entire cohort, 30-day mortality was 7% (n = 13), and all-cause and cardiovascular 1-year mortality was 12% (n = 22) and 8% (n = 14), respectively. There were 3 procedural deaths due to cardiac tamponade (left ventricular wire perforation, right ventricular pacing lead perforation, and annulus rupture). There was no difference in mortality according to the anesthesia strategy (log rank p = 0.21) (Figure 3).
On multivariate analysis, only post-operative stroke or TIA was significantly associated with 1-year mortality (odds ratio: 0.24; 95% confidence interval: 0.08 to 0.72; p = 0.01).
The VARC-2–defined 30-day combined safety and efficacy endpoint occurred in 80.4% (n = 140) and 87.9% (n = 153), respectively. Minor vascular complications occurred in 20 patients (11%): 11 involved the carotid vascular access and 9 involved the femoral venous access. There were no major vascular complications involving the carotid access. New permanent pacemaker was required in 18.9% (n = 33), all with self-expanding devices. There were 15 (8.6%) cases of new onset atrial fibrillation. No prosthesis thrombosis, endocarditis, or other prosthetic valve–associated complications were observed. Post-implantation hemodynamics demonstrated a reduction in transvalvular mean gradient from 44.4 ± 12.9 mm Hg to 8.4 ± 1.6 mm Hg (p < 0.001), and an increase in the effective orifice area from 0.76 ± 0.28 cm2 to 1.86 ± 0.32 cm2 (p < 0.001).
There was no difference in 30-day safety (86.5% MIS vs. 77.8% GA; p = 0.18) or efficacy (94.2% MIS vs. 85.2% GA; p = 0.09) between the anesthesia strategies. No significant differences between the 2 groups were observed in the incidence of VARC-2–defined complications (myocardial infarction, acute kidney injury, and vascular and bleeding complications) (Table 2). Post-procedural aortic regurgitation grade ≥2 occurred in 8.6% (n = 15) and was not significantly different between the anesthesia groups (9.6% MIS vs. 8.1% GA; p = 0.76). The average length of hospital stay was 9.2 ± 7.5 days, and was significantly longer in the GA group compared with the MIS group (11.3 ± 8.6 days vs. 6.0 ± 3.3 days; p < 0.001).
There were 10 (5.7%) 30-day VARC-2–defined cerebrovascular events (Table 3): 4 (2.2%) stroke (modified Rankin scale: 3, 2, 1, and 1) and 6 (3.4%) TIA, as assessed by clinical and neuroimaging criteria. These events only occurred in patients managed under GA (p < 0.001), and all occurred in the first two-thirds of our experience. Importantly, the duration of the procedure was not different between the anesthesia groups. The cerebrovascular events were localized as ipsilateral (n = 2) or contralateral (n = 6) to the carotid vascular access site. Clinical features of the events included confusion (n = 1), hemiparesis (n = 2), hemiplegia (n = 6), and aphasia (n = 1), neuroimaging showed new ischemic lesions in the 4 stroke cases (multiple embolic lesions). Two patients who suffered a stroke had pre-TAVR atrial fibrillation. Pre-operatively, all patients were prescribed antiplatelet therapy and all received intraprocedural heparin. Three additional cases of transient nonfocal global encephalopathy with normal neuroimaging were not defined as stroke/TIA.
At 30 days, the rate of stroke or TIA was 5.7%, increasing to 6.8% (n = 12) at 1 year. Late cerebrovascular events included 3 strokes: an ischemic stroke causing hemiparesis on day 34, an ischemic stroke causing aphasia and visual field defect on day 51, and later a hemorrhagic stroke on day 409. In all, 2 strokes were disabling, and 5 were nondisabling (modified Rankin scale: 3, 1, and 1). Patients who suffered a stroke or TIA had higher 1-year mortality than did those that did not (p < 0.001).
Herein, we describe the largest series of patients undergoing transcarotid vascular access for TAVR. The main findings from this study are that transcarotid TAVR appears safe and feasible, with a 30-day stroke or TIA rate of 5.7%, and that it may be managed with minimally invasive or GA strategies.
Transcarotid TAVR with a self-expanding prosthesis was first performed using the Medtronic CoreValve in Lille, France, in 2009 (11). This technique has subsequently been adopted by other centers, and has evolved to include the use of local anesthesia (5) and other valve types (3). In the current study, we compared for the first time 2 anesthesia strategies for transcarotid TAVR. An MIS has previously been described for transfemoral TAVR with favorable results (13,14), but there are no data on this technique for transcarotid vascular access. We introduced the MIS technique on the basis of encouraging data from TAVR and carotid endarterectomy studies (15–17). Indeed, The EUROSTAR (European Stent/Graft Techniques for Aortic Aneurysm Repair) registry suggested reduced morbidity and possibly mortality with a locoregional anesthesia approach among high-risk patients undergoing endovascular aortic repair (17). Potential mechanisms by which an MIS may affect morbidity include early mobilization, avoidance of drugs potentially inducing hemodynamic compromise, avoidance of endotracheal intubation, mechanical ventilation (18), and thus avoidance of complications from these interventions. GA also involves volatile anesthetic agents that have been associated with immunosuppression and an increased risk of post-operative pneumonia (19).
Indeed, studies comparing local and GA with transfemoral TAVR have demonstrated shorter procedure time and mobilization when compared to GA (13,20). Consistent with these data, we observed a shorter hospital length of stay with the MIS compared with the GA group. Importantly, the MIS approach also affords the opportunity to assess cerebral perfusion during procedure. This appears to have been of vital importance to the 2 patients with positive carotid cross-clamp tests, who may have manifested post-operative stroke but for the ability to change the vascular access strategy. This test appears to be of additive value to the monitoring of cerebral oximetry (21).
Of course, the MIS for carotid TAVR requires a period of adjustment for the TAVR team. A formal detailed discussion with the patient and his or her family is of paramount importance, so as to avoid confusion during the procedure. Furthermore, communication between the team members during the procedure is critical to success, with 1 nurse staying with patient to monitor the clinical neurological status and no sedation until the cross clamp. The proximity of the vascular access to the patients’ head can create some potential problems for both patient and operator. Foremost among these is the potential for the patient to move during valve deployment due to access site discomfort. Generous local anesthesia and an appropriate level of sedation is therefore fundamental. Overall, the requirement to convert from an MIS to GA strategy was low (5.7%), and similar to rates reported for transfemoral TAVR (22).
In the current study, the 30-day stroke or TIA rate was 5.7%, with 4 strokes (2 major, 2 minor), and 6 TIAs at 30 days. This stroke rate is similar than that observed in real-world transfemoral TAVR registries (1). As previously described (4), the frequent contralateral localization of neurological events and the pattern of post-infarction magnetic resonance imaging suggests that many of these events may not related to implementation of the carotid artery. Rather, likely etiologies include: debris embolization during balloon valvuloplasty and valve deployment, hypotensive episodes triggered by anesthetic agents and rapid ventricular pacing, atrial fibrillation, and inadequate collateral perfusion through the circle of Willis. Nevertheless, carotid artery intervention, by its very nature, must be associated with a risk of stroke, and therefore should only be performed by clinicians with considerable experience of carotid artery surgery. The TAVR team should remain particular with respect to vascular screening, assessment of collateral blood flow, anticoagulant and antiplatelet therapy, and periprocedural management of the carotid artery.
We observed a significantly higher rate of cerebrovascular events with the GA strategy compared with the MIS (8.2% vs. 0%; p < 0.001). Potential explanations for this result include a procedural learning curve (first performed with GA; no stroke or TIA in the last one-third of GA procedures), the recent move toward less balloon aortic valvuloplasty (MIS is more recently used), and the play of chance (small numbers of events). However, the vascular access sheath size and procedural duration were identical between anesthesia groups. Furthermore, the positive carotid-cross clamp tests observed in this series suggests that the MIS may have real potential in reducing cerebrovascular events among these patients.
Comparison to nonfemoral approaches
Patients requiring a nonfemoral approach are typically at increased risk compared with those suitable for a femoral procedure (1). The transapical approach was initially considered the nonfemoral approach of choice. However, increased mortality compared to transfemoral TAVR, probably relating to increased myocardial injury and respiratory failure, have seen this approach diminish in popularity (23). A direct transaortic approach has more recently been developed (24). This approach continues to require GA and is not suitable in cases of porcelain aorta, or advanced respiratory failure. The reported 30-day mortality (8%) with this technique compares unfavorably to the current study, though the risk of stroke is low, at 2% (25). The 30-day mortality in patients undergoing the subclavian approach is reported to be 6%, with stroke rates of 2% to 3% (26). This technique may be unsuitable for patients with severe axillary or subclavian artery disease or among those with patent internal thoracic artery grafts. Taken together, these data suggest that in patients requiring nonfemoral TAVR an individualized approach to vascular access is appropriate.
Who should have MIS for this approach?
MIS may be more favorable in the following clinical situations: severe pulmonary disease or immunodeficiency (avoid pneumonia or delayed extubation), unstable hemodynamics (avoid risk of further hypotension with induction), and mild-moderate dementia (avoid further cognitive dysfunction or delirium with anesthesia). If the patient has anatomy with questionable cerebral perfusion secondary to inadequate collateral circulation, then an MIS may be beneficial. In the present series, 4 (7.6%) of the patients were converted from MIS to GA; however, because of the limited number of patients, no conclusions can be made regarding better patient selection.
The need for intraprocedural transesophagal echocardiography and significant patient discomfort under previous MIS procedures are relative contraindications to the MIS technique. A common carotid artery luminal diameter ≤6.0 mm and a short neck with significant adiposity are true contraindications. Furthermore, patients with anticipated difficult airway are unsuitable for this approach.
This prospective study is nonrandomized and is limited by the flaws inherent to this type of analysis, and in particular, the retrospective nature of data analysis, the small size of the cohort, and noncentralized data analysis and endpoint adjudications. These limitations can affect the validity of the study conclusions. Several factors, including the small number of patients, patient selection using MSCT, and operator experience of the technique could account for some of the difference between MIS and GA. Device iteration with smaller sheath size may also play a role.
The results achieved reflect those of 2 centers specialized in transcarotid TAVR and must be confirmed in a larger patient series. Importantly, it is possible that the rate of neurological events has been underestimated, as systematic evaluation by a neurologist was not performed prior to and following TAVR. We have been, however, very focused on neurological outcomes, and there was a low threshold for neurologist evaluation or neuroimaging. In addition, we mostly used first-generation transcatheter valves and new generation valves are likely to reduce vascular complications.
Transcarotid TAVR appears to be both feasible and appears safe, with high procedural success, 30-day mortality of 7.4%, and a 30-day stroke or TIA rate of 5.7%. These procedures may be performed using local or GA, and the former may have a lower risk of stroke. Further study is required to confirm these results.
WHAT IS KNOWN? Transcarotid TAVR has been shown to be feasible and safe.
WHAT IS NEW? Transcarotid TAVR procedures may be performed using local or GA with similar outcomes, and the former may have a lower risk of stroke.
WHAT IS NEXT? Transcarotid TAVR under MIS can be proposed as second choice approaches when transfemoral access is not available, with satisfying results at 1-year follow-up.
The authors would like to thank Alan Grant for his kind review of the manuscript.
Dr. Sudre has served as a consultant for Edwards Lifesciences and Medtronic. Dr. Modine has served as a proctor and consultant for Medtronic and Microport. Dr. Mylotte has served as a proctor for Medtronic and Microport. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Abbreviations and Acronyms
- general anesthesia
- minimally invasive strategy
- magnetic resonance angiography
- multislice computed tomography
- transient ischemic attack
- transcatheter aortic valve replacement
- Received May 27, 2016.
- Revision received August 2, 2016.
- Accepted August 11, 2016.
- American College of Cardiology Foundation
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