1. The Effect of Carotid Calcification on Outcomes of Transfemoral and Transcarotid Artery Stenting in the VQI
Michael neilson, MD1
Mahmoud malas, MD, MHS2
Grace wang, MD3
Vikram Kashyap, MD4
Raghu motaganahalli, MBBS4
Marc Schermerhorn, MD5
Jack cronenwett, MD6
Jens Eldrup-Jorgensen, MD1
Brian Nolan, MD1
1-Maine Medical Center, 2-UCSD, 3-UPENN, 4 Indiana University, 5- Beth Israel Deconess, 6-Dartmouth

2. No disclosures

3. 1
Introduction
Carotid artery calcification has been previously reported as a risk factor for post-operative neurologic outcomes following transfemoral carotid stenting (TF-CAS).1
Transcarotid Artery Revascularization (TCAR) has been shown to be safe and effective treatment of carotid stenosis, especially in otherwise high risk individuals.2
1.AbuRahma AF, DerDerian T, Hairi N et al. Anatomic and technical predictors of perioperative clinical outcomes after carotid artery stenting. J Vasc Surg. 2017;66(2):
2. Wang Sk, Fajardo A, Sawchuk AP, et al. Outcomes associated with Transcarotid artery revascularization-centered protocol in high risk carotid revascularization using the ENROUE neuroprotection system. J Vasc Surg. 2019;69(3):

4. Carotid Calcification in VQI
Reported since 2016
Subjective report of degree of calcification of carotid lesion
Reported as degree of circumferential calcification
<25%, 25-50%, 51-99%, 100%
Since 2016 the degree of calcification of the target lesion has been reported to the VQI. This is done in four ranges, ie < 25%, 25-50%, 51-99% or 100% circumferential calcification.

5. Objective
Compare outcomes of TF-CAS and TCAR stratified by degree of circumferential carotid calcification in the VQI

6. Methods Retrospective cohort study of all CAS in the VQI, 2016-2019
Analyzed by degree of calcification
<25%, 25-50%, 51-99%, 100%
Primary endpoint
Stroke occurring during index hospitalization
Secondary Endpoints
Major adverse cardiac events (MACE), hemodynamic suppression
Multivariate logistic regression analysis to predict carotid calcification
MACE included MI, dysrhythmia, or CHF while hemodynamic suppression included hypotension or bradycardia
Multivariate logistic regression was used to identify risk factors for carotid calcification

7. Results Carotid Stenting in VQI, 2016-2019 N=4834 (n=1890) (n=2944)
39%
(n=1890)
61%
(n=2944)
Between 2016 and 2019 there were 4,834 CAS procedures done in the VQI, 61% were TF with 39% being TCAR

8. Degree of Calicification
Patient Demographics
Degree of Calicification
<=25% (n=2400)
26-50% (n=885)
51-99% (n=1,361)
100% (n=188)
p-value
Age 68 71 72 73
0.022
Female
35%
34%
37%
43%
0.050
Symptomatic (stroke or TIA)
61%
64%
60%
0.409
Primary lesion
70%
86%
87%
88%
0.001
Hypertension
84%
91%
MI or agina
25%
26%
30%
23%
0.006
Prior PCI or CABG
32%
40%
Prior dysrhythmia
16%
20%
24%
CHF
14%
19%
Current smoker
38%
39%
0.971
COPD
28%
29%
27%
ESRD 1% 2%
0.162
Current ASA
83%
85%
Current P2Y
73%
78%
80%
71%
Current statin
Triple therapy
58%
63%
66%
Non-white race
13%
10% 9%
0.015
Patient demographics stratified by degree of calcification showed a high burden of traditional risk factors for atherosclerosis, there appeared to be an association between increases degrees of calfication and age, female sex, CHF, and primary lesion as opposed to redo lesion. Increasing degrees of calcification was not associated with symptom status.

9. Primary Outcomes TCAR p= 0.943 TF-CAS p< 0.001
In terms of our primary outcome, in the tF-CAS cohort there was a statistically significant increasing risk of post-operative neurologic event in those with increasing degree of calcification with a a rate of 2.2% in those with minimal calcification, up to 9.3% in those with 100% calcification. In contrast, those in the TCAR group had no statistically significant deifference in neurologic outcome based on degree of calcification, with a range of 1.2&% to 2.3%.
TCAR p= 0.943
TF-CAS p< 0.001

10. Secondary Outcomes TF-CAS p< 0.001 TCAR p < 0.001
Patients with minimal rates of calcification in the TF-CAS had minimal rates of hemodynamic suppression, while those in the TCAR cohort had increasing rates of hemodynamic suppression with increasing rates of calcification.
TF-CAS p< 0.001
TCAR p < 0.001
** Hypotension and/or bradycardia

11. Secondary Outcomes TF-CAS p = 0.21 TCAR p = 0.02
Those undergoing TF-CAS had a trend towards increasing MACE for increasing degrees of calcification, though this was not statistically significant.
TF-CAS p = 0.21
TCAR p = 0.02

12. Predictors of Carotid CalcificationOR
p value
95% CI
Age > 80
2.22
0.001
1.80
2.74
Ae 70 to 79
1.69
1.41
2.03
Age 60 to 69
1.42
1.178
1.714
Atherosclerotic lesion
2.67
2.28
3.10
COPD
1.34
1.17
1.53
CHF
1.27
0.004
1.08
1.51
HTN
1.33
0.002
1.12
1.61
Prior CABG or PCI
1.13
0.048
1.01
1.30
Diabetes
0.015
1.03
Non white race
0.74
0.614
0.90
On multivariate logistric regression, increasing age, as well as a number of co-morbidities including atherosclerotic lesion, COPD< CHF, HTN, prior cardiac intervention and diabetes were also associated with carotic calcification. Non-white race was inversley associated with carotid calcification.

13. Limitations
Self reported degree of calcification within VQI, not adjudicated
Retrospective in nature, can only show association, not causation

14. Summary
Increasing degree of calcification is associated with increasing rates of post-operative CVA following TF-CAS
This is not seen after TCAR
Rate of hemodynamic suppression increases with increasing calcification following both procedures, particularly following TCAR, but this needs further investigation
Multiple risk factors for increasing degree of carotid calcification
Multiple risk factors for increasing degrees of calcification which may

15. Conclusions
TCAR may be an acceptable alternative even in patients with extensive calcification, though with caution
Can predict possibility of carotid calcification which may effect treatment type and pre-operative imaging
TCAR may be an acceptable alternative even in patients with extensive calcification, though caution must be taken in regards to possible hemodynamic suppression
Further research is needed in the form of a prospective trial to fully elucidate the relationship between carotid calcification and post operative events when considering CAS

16. Thank You

17. Degree of Calicification
Outcomes
Transfemoral
Degree of Calicification
<=25% (n=1568)
26-50% (n=512)
51-99% (n=757)
100% (n=107)
p-value
Postop Neuro event
2.2%
2.9%
4.4%
9.3%
0.001
Postop Hypotension
12%
17%
16%
0.015
Bradycardia
11%
15%
0.034
HD suppression
20%
26%
25%
23%
0.010
Cardiac event
2.8%
2.1%
5.6%
0.21
TCAR
<=25% (n=832)
26-50% (n=373)
51-99% (n=604)
100% (n=81)
Postop neuro event
2.3%
1.2%
0.943
Postop hypotension
0.004
10%
13%
0.139
21%
39%
Postop cardiac event
2.4%
0.3%
2.6%
0.02
In terms of our primary outcome, in the tF-CAS cohort there was a statistically significant increasing risk of post-operative neurologic event in those with increasing degree of calcification with a a rate of 2.2% in those with minimal calcification, up to 9.3% in those with 100% calcification. In contrast, those in the TCAR group had no statistically significant deifference in neurologic outcome based on degree of calcification, with a range of 1.2&% to 2.3%.

18. Results
P=0.001
P=0.001
P=0.04
P=0.253
There was a statistically significant difference between types of interventions at all levels of calcification except at 100% calcification.

19. Results: Procedural Details
Degree of Calicification
<=25% (n=2400)
26-50% (n=885)
51-99% (n=1,361)
100% (n=188)
Pre and postdilate
30%
28%
24%
25%
Pre dilate only 6% 5% 7%
Post dilate
65%
68%
69%
70%
The details of the procedure showed that there was an increasing use of post dilation balloon use with increasing degrees of calcification, which was statistically significant.
P=.0011