evidence for endarterectomy in severely diseased coronary arteries during CABG

1. Ten-Year Experience of Coronary
Endarterectomy for the Diffusely Diseased
Left Anterior Descending Artery
Kosaku Nishigawa, MD, Toshihiro Fukui, MD, Masataka Yamazaki, MD, and
Shuichiro Takanashi, MD
Department of Cardiovascular Surgery, Sakakibara Heart Institute, Tokyo, Japan
JOURNAL CLUB
Dr. Anuj Mehta
DNB-CTU
GKNM Hospital,Coimbatore

2. • Coronary endarterectomy (CE) is a surgical option for a diffusely dis
eased coronary artery.
• This study evaluated the clinical and angiographic outcomes
• of CE for a diffusely diseased left anterior descending
• artery (LAD) using the internal thoracic artery (ITA).

3. Patients and Methods
• The Sakakibara Heart Institute
• Retrospective observational study
Patient Characteristics
• September 2004 to September 2014,
• 1,894 patients underwent isolated CABG
• 188 underwent CABG with concomitant CE for a diffusely
diseased LAD and were included in the analysis.

5. OPERATIVE
TECHNIQUE
• Complete myocardial revascularization by using the off-pump
technique whenever feasible.
• CE combined with off-pump CABG performed to avoid the
adverse effects of cardio- pulmonary bypass.
• All arterial grafts were harvested in a skeletonized fashion
• Before the endarterectomy of the LAD, the other target vessels
were bypassed in the usual manner.

6. • CE when the atheromatous plaques were severe and
circumferential,
• which could not be excluded by extensive
reconstruction without CE and affected its side
branches (septal perforators and diagonal branches)
• or the needle could not pass the vessel wall because
of severely calcified plaques.
• CE with stent removal for long-segment in-stent
restenosis involving the side branches .

7. • The coronary arteriotomy was begun in the middle portion of the LAD
• Dissection- fine forceps and a spatula.
• The proximal end - distal to the most proximal lesion (to prevent competitive
flow through the native coronary artery.)
• The distal incision was extended to the nondiseased segment.The divided
intima was tacked with 8-0 polypropylene sutures to prevent flap formation.
• The ITA was anastomosed using 8-0 polypropylene sutures in onlay- patch
fashion .
• After completing all anastomoses, and a transit-time flow meter were used to
confirm graft patency.

8. Anticoagulation Protocol
• a continuous I.V. infusion of LMWH(5,000 IU/d) continued un
• Low- dose aspirin (100 mg/d)- indefinitely.
• Clopidogrel (75 mg/d) -1 year
• Warfarin - 3 months
• Target INR 2.0 to 2.5

9. • Early postoperative - before discharge.
• Diagnostic angiography - on symptomatic patients .
• 1 year after the operation .
• Patients who died, refused angiography, > 75 years, or had renal dysfunction (serum
• Since mid-2012, optical coherence tomography (OCT) to assess the luminal charac
Angiographic Evaluation and Clinical Follow-Up

10. • Follow-up -review of medical records, mailed questionnaire, or tel
• Follow-up was continued until an end point of death or completion
• 7 patients were lost; completed in 96.3% of patients.
• The median follow-up period was 5.8 years (range, 0.1 to 11.0 years

11. • IBM SPSS Statistics 19.0 software (IBM Corp, Armonk, NY).
• Normally distributed continuous variables- expressed as the mean ` SD,
• skewed continuous variables- the median with the range.
• Categoric variables - frequencies and percentages.
• Preoperative and postoperative EF was compared using the paired Student t test.
• p value <.05 - statistically significant.
• Cumulative survival rate and the MACCE-free rate were estimated using the Kaplan-Meier method.
Statistical Analysis

12. • The left ITA (LITA) in 179 patients (95.2%)
• the right ITA in 9 patients (4.8%).
• Off-pump CABG was performed in 185 patients (98.4%);
• 9 patients required on-pump conversion, for a conversion rate of 4.9%.
• POMI occurred in 17 patients (9.0%).
• The mean postoperative EF- 0.54
• There were 2 operative deaths (1.1%)
• During follow-up, there were 27 deaths (14.4%), including operative deaths (5 cardiac and 22
noncardiac deaths).
• 30 patients underwent PCI and 1 underwent redo CABG during the same period;
• no late MIs
• Cerebrovascular accidents were observed in 11 patients.
Results

14. • Freedom from all-cause death at 5 years -
89.3% ` 2.4%
• Freedom from MACCEs at 5 years was
74.0% ` 3.3%

15. • Early postoperative angiography was performed in 178 patients (94.7%) at a median of 7 days (ra
• The rate of perfect patency - 91.6% (163 of 178).
• Occluded ITA and LAD - 4
• Occluded LAD with a patent ITA - 8
• Anastomotic stenosis -2
• Occlusion of the LITA caused by dissection - 1
• Of these 15 patients,
• 9 underwent PCI
• 6 were prescribed strict anticoagulation treatment and monitored.
Angiographic Outcomes

16. • Follow-up angiography was performed in 148 patients (78.7%) with a mean of 13 ` 6 months
after the operation.
• Follow-up angiography in 10 of 15 patients with anastomotic failure at early postoperative
angiography.
• Occluded ITA and LAD - 2
• Occluded LAD with a patent ITA - 1
• new diffuse luminal narrowing of the ITA (string sign) with a patent LAD - 2
• New occlusion of the ITA with a patent LAD -1
• Consequently, the rate of perfect patency of both the ITA and reconstructed LAD at follow-up
angiography was 96.6% (143 of 148)

17. the diameter of the reconstructed
LAD had decreased to match the
diameter of the LITA
patent LITA graft anastomosed
to the endarterectomized LAD

18. Early postoperative and follow-up optical coherence tomography (OCT )was performed in 8
patients.
complete endothelialization of the
endarterectomized LAD and a circumferential
ITA intima.
Early postoperative OCT showed the denuded
adventitia of the endarterectomized LAD had a
rough

20. • Shapira and colleagues found that death and morbidity after CABG with CE were similar to
those after CABG without CE and that CE itself was not an independent predictor of POMI.
• Tiruvoipati and colleagues observed that the higher mortality rate of CE - related more to
comorbidities, such as age, renal deficiency, diabetes mellitus, and decreased left ventricular
function, than to the CE procedure
• The CE procedure itself is no longer considered to be a risk factor for poor surgical outcomes.
• The relatively high rate of POMI (9.0%) in the present study could have resulted from the
inclusion of patients with an enzymatic definition of POMI even if they were asymptomatic and
had no echocardiographic or electrocardiographic findings.
• In the present study, the operative mortality of patients undergoing CE was 1.1%, which is
superior to other clinical reports .

21. • CE 1) closed (traction) 2) open (direct vision) methods.
• Closed endarterectomy is simpler and easier to reconstruct
• but complete removal of the atheromatous plaques is frequently difficult
• open endarterectomy allows complete removal of atheromatous plaques from the
main vessel and the side branches under direct vision

22. • Nishi and colleagues reported a better midterm angiographic patency rate for
CE with a long arteriotomy than for traction endarterectomy.
• The LAD has diagonal branches and septal perforators that occur in the 2
different planes.
• To achieve the complete removal of diffuse atheromatous plaques involving
these side branches, CE under direct vision with a long arteriotomy for a
diffusely diseased LAD has shown better results.

23. • Retrospective observational study at a single center,
• No control group.
• The number of patients was relatively small.
• Most of the patients in this series underwent CE with off-pump CABG. Th
• the outcomes of CE with off-pump CABG could not be compared with those of CE with
• Follow-up angiography was performed for only 78.7% of patients.
Study Limitations

24. • CE for a diffusely diseased LAD with onlay-patch grafting using the
skeletonized ITA provides satisfactory early and long-term outcomes.
• Favourable angiographic patency rates.
• When conventional grafting is difficult because of diffuse calcifications or
because diffuse atheromatous plaques affect the side branches
• CE may be the only surgical option to achieve complete revascularization
in patients with a diffusely diseased LAD.
Conclusions