Cardiovascular Journal of Africa: Vol 30 No 1 (January/February 2019)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 30, No 1, January/February 2019

AFRICA

side branches.

Incomplete revascularisation is an important

factor increasing peri-operative mortality and morbidity rates.

Different surgical alternatives have been reported in diffuse LAD

lesions in order to avoid this.

Kato

et al

reported that in patients treated with long-

segment LITA patchplasty in diffuse coronary artery disease,

patients with and without endarterectomy had similar operative

and long-term outcomes. Similarly, patients who underwent

LITA patchplasty without endarterectomy were reported

to have similar results to patients treated with conventional

CABG.

In our patients with LITA onlay patchplasty without

endarterectomy on the beating heart, peri-operative MI was

found to be 3.7% and the mortality rate was 5%. Our results are

acceptable for patients with diffuse LAD lesions.

The most important advantage of endarterectomy is to

increase perfusion of the myocardial tissue from the side

branches.

However, in patients undergoing endarterectomy,

peri-operative MI and postoperative complications in the first 30

days (low cardiac output, MI, renal dysfunction) are seen most

frequently.

After endarterectomy, peri-operative MI and hospital

mortality has been reported as 1.5–8% and 2–6.5%, respectively.

For patients undergoing endarterectomy, the mortality rate

increased 3.9-fold and peri-operative MI increased 2.9-fold in

diffuse LAD lesions compared to isolated CABG.

With increased surgical experience and equipment, even

though operative mortality rates after endarterectomy were close

to that of conventional surgery, the rate of postoperative MI was

higher in patients undergoing endarterectomy.

In a study where

99 patients who underwent patch angioplasty on the LAD artery

and 71 patients who underwent endarterectomy were compared,

early and long-term survival were found to be similar.

In a meta-analysis in which 63 730 CABG patients were

evaluated, the early-stage results of endarterectomy were

reported to be poor, especially in diffuse LAD lesions and high-

risk patients.

Therefore in consecutive LAD lesions, bypass on

two intact regions of the LAD may be preferred, or patchplasty

without endartercetomy could be performed on diffuse LAD

lesions. In our clinic, in consecutive LAD lesions, we extend

the arteriotomy from the distal part of the first stenosis to the

distal part of the second stenosis. Then we apply onlay LITA

patchplasty to this area.

Due to the low risk of atherosclerosis, long-term patency

rates after LITA patchplasty are higher.

In the study of Myers

et al

where saphenous vein patchplasty and LITA onlay

patchplasty were compared after LAD endarterectomy, although

peri-operative MI and mortality rates were found to be similar

(4%) in both groups, five- and 10-year survival rate was 87.1 and

49.4% in the group with patchplasty with the LITA, and it was

78.6 and 45.4% in the saphenous vein patchplasty group.

In another study, peri-operative mortality and MI rates of

LAD endarterectomy and LITA patchplasty were reported at 2.7

and 12.2%, respectively.

In 128 patients who underwent a control

angiography after LITA patchplasty, the five-year patency rate

was found to be 91%.

In our clinic, we routinely use the LITA

during application of patchplasty to the LAD. Appropriate to

the incision of the LAD artery, we perform onlay patchplasty by

preparing the LITA graft without plaque exclusion.

In diffuse LAD lesions, onlay patchplasty can be performed

with the saphenous vein or LITA without excising the plaque.

In the study by Fukui

et al

with 252 patients, where they used

a LITA patch without LAD endarterectomy in 73% of the

patients, they performed the arteriotomy at an average of 4.3

cm and reported the operative mortality rate to be 1.6% and the

peri-operative MI rate at 6.4%.

In diffuse coronary artery disease, Kato

et al

reported a

10-year survival rate of 74% after LAD reconstruction with the

LITA, and a freedom from cardiac-related death at 92%. In this

group, no difference was found in terms of survival rate between

patients who did or did not undergo endarterectomy.

In our

patient group, postoperative MI rate was 3.7% and mortality was

5.5%. Although these are acceptable rates, there is a need for a

larger study series.

There is more collateral development in diffuse disease

of the LAD and patients better tolerate off-pump CABG.

Therefore off-pump CABG and endarterectomy can be safely

used in diffuse LAD lesions. Open endarterectomy and LITA

onlay patchplasty of diffuse LAD lesions on the beating heart

improves postoperative results.

Fukui

et al

applied bypass on

the beating heart in 80% of 252 patients who underwent LITA

patchplasty with or without endartectomy. However, Nishigawa

et al

reported a peri-operative MI rate of 9% in patients who

underwent patchplasty with LITA after endarterectomy on the

beating heart. This rate was higher than that of conventional

surgery and our postoperative MI rates.

Prabhu

et al

successfully performed LITA patchplasty

without endarterectomy on the beating heart in 104 patients,

and control angiography of 16 patients revealed that the grafts

were patent.

In our patients, we performed the operation on

the beating heart. All of the patients tolerated off-pump CABG

surgery and no emergency conversion to cardiopulmonary

bypass was needed in any patient.

During the endarterectomy, where the endothelial layer is

dissected, the subendothelial tissue increases the risk of early-

stage thrombotic occlusion in the anastomotic line. Nishigawa

et al

reported the thrombotic occlusion rate of a reconstructed

LAD at 6.4% despite a dual anti-aggregant and anticoagulant

combination in patients with LITA onlay patchplasty after

endarterectomy.

Prevention of endothelial damage prevents complications

arising from intimal damage in the early postoperative period.

When a simple bypass cannot be performed due to diffuse LAD

Table 2. Operative findings

Variables

Value

No of coronary artery anastomoses,

(%)

CABG × 1

2 (3.7)

CABG × 2

15 (27.8)

CABG × 3

25 (46.3)

CABG × 4

11 (20.4)

CABG × 5

1 (1.8)

Length of LAD arteriotomy (mm)

42.8

13.3

Drainage (ml)

451

255

Revision,

Erythrocyte replacement (units)

0.5

IABP,

(%)

5 (9.3)

Postoperative EF (%)

50.2

6.1

Postoperative atrial fibrillation,

(%)

6 (11.1)

Duration of hospitalisation (days)

9.3

7.1

CPB: cardiopulmonary bypass, EF: ejection fraction, IABP: intraaortic balloon

pump, LAD: left anterior descending artery.