Discussion
For patients with gastrointestinal malignancies and severe coronary
stenosis, the choice between staged or simultaneous surgeries is still
controversial. Staged radical resection of the tumor following CABG has
been the traditional approach in the past 9, 10.
However, it has been reported that a second non-cardiac surgery within
30 days has a higher risk of death and cardiovascular complications. In
general, it is recommended that the subsequent operation be performed
six to 12 weeks after grafting 11. In addition, the
general nutritional status of gastrointestinal tumor patients was lower,
and the recovery time after CABG was longer. Takahashi and colleagues
reported that the second operation was delayed in three of nine patients
who received staged surgery due to slow recovery following CABG, with an
average interval of seven weeks 12. Importantly, the
tumor may progress while patients are awaiting radical surgery.
Additionally, heparinization during CABG and postoperative antiplatelet
therapy may lead to gastrointestinal malignancy bleeding, which could be
life-threatening. Therefore, to avoid the above shortcomings of staged
surgeries, concurrent surgeries may be a better option. In addition, the
concurrent surgeries can also reduce the immunosuppression caused by
twice the anesthesia, reduce the long-term recurrence rate of the tumor
caused by blood transfusions 13, reduce the pain
experienced by patients, and it has health and economic benefits.
More than 20 patients with gastric cancer and 10 patients with bowel
cancer have received simultaneous CABG and radical gastrointestinal
tumor resection 14-16. There were no perioperative
deaths, and no occurrences of postoperative myocardial infarction or
heart failure. A total of five patients at our center were discharged
smoothly without adverse events. There were no perioperative deaths, and
no serious cardiovascular events or anastomosis fistulas following the
concurrent surgeries. Two of the gastric cancer patients died at 28 and
37 months due to tumor metastasis, which may be related to the late
postoperative pathological stage. Our case series suggests that patients
with gastrointestinal tumors and severe coronary heart disease who
underwent concurrent OPCAB and radical resection of their
gastrointestinal tumors may have better short-term results, and the
long-term prognosis may be related to tumor staging.
Although concurrent surgeries have many advantages over staged
surgeries, combined surgery often takes a long time and is more
traumatic to the patient. Therefore, it is necessary to strictly control
the surgical indications for this type of surgery. Shapira et al.reported that CABG in patients with left ventricular ejection fraction
(LVEF) < 30% can be performed with low mortality, but with
higher morbidity and longer length of hospital stay compared to patients
with LVEF > 30% 17. Zhang and colleagues
proposed that concurrent surgery is not recommended for patients with
LVEF < 45% 18, and Davydov and colleagues
have stated that LVEF < 20% is a contraindication for
concurrent surgery 16. However, Takahashi et
al. reported that concurrent CABG and radical gastrointestinal tumor
resections were safe and feasible in patients with low LVEF14. At present, the ejection fraction (EF) value of
patients undergoing concurrent surgery is generally > 30%,
and the average LVEF in our study group was 56.8% (45-65%). In
general, low LVEF does not affect the simultaneous operations, but if it
is too low (especially < 20%), it may be contraindicated.
The management of patients with severe coronary stenosis who present
with acute heart failure may be a more difficult challenge for cardiac
surgeons. Most scholars believe that left heart failure that requires
large doses of cardiotonic drugs or mechanical circulatory support is a
contraindication to simultaneous surgery, and these patients should be
operated on in stages 14. Among our patients, OPCAB
was urgently performed on case 2 because of acute left heart failure.
After OPCAB, the patient had stable hemodynamics and no obvious bleeding
tendencies, so he immediately underwent radical resection of gastric
cancer. This is the first case of heart failure that underwent
simultaneous CABG and radical tumor resection, which has provided a
potential solution for the treatment of such patients.
In addition to the condition of the heart, the surgery required for the
abdominal tumor is also an important factor in considering whether to
perform the operations at the same time. Tsuji et al . reported
that CABG and total gastrectomy at the same time have a higher risk of
mediastinal infection, and proposed that CABG and total gastrectomy
should be performed in stages, with the total gastrectomy being
performed three to six weeks after CABG 10. Takahashi
suggested that patients with severe coronary heart disease undergoing
resection of high-risk tumors, such as esophageal cancer and pancreatic
cancer, should also undergo staged surgeries 14. In
addition, Komokata and colleagues published a report on an 83-year-old
patient with chronic obstructive pulmonary disease (COPD) who underwent
simultaneous aortic valve replacement and radical gastric cancer
surgery, and died of respiratory failure following the operation,
suggesting that advanced age and COPD are high risk factors for poor
outcomes in simultaneous surgeries 15.
CABG and percutaneous coronary intervention (PCI) are both strategies of
coronary revascularization, but making a choice between the two is still
controversial. The SYNTAX trail showed that CABG had a mortality benefit
over PCI in patients with multi-vessel disease, particularly in those
with diabetes and higher coronary complexity 19. For
patients with coronary heart disease undergoing non-cardiac surgery, it
is recommended to implant bare stents instead of drug-eluting stents,
because this can shorten the time interval between subsequent operations20. The ideal interval to perform non-cardiac surgery
after implantation of bare stents is three months, when the principle
negative events (death, myocardial infarction, stent thrombosis and
revascularization) are lowest 21. Therefore, CABG may
be a more reasonable choice for revascularization compared to PCI for
patients with multi-vessel disease undergoing surgery for
gastrointestinal cancer. After multidisciplinary discussions between
cardiologists and cardiac surgeons, we finally decided to adopt CABG as
the strategy of coronary revascularization.
Randomized controlled clinical trials have shown that OPCAB and on-pump
CABG have a similar early and late graft patency rate, revascularization
rate and long-term prognosis 22. For surgeons with
excellent surgical skills, the incidence of morbidity (stroke, atrial
fibrillation and infection) after OPCAB is lower 23.
Compared with on-pump CABG, OPCAB can reduce the risk of
gastrointestinal bleeding caused by heparinization, reduce the systemic
inflammatory response, and will not enhance tumor progression due to
cardiopulmonary bypass 24. Similar to the suggestion
offered by Komokata et al. , OPCAB may be more reasonable for
cancer patients. The use of arterial grafts is beneficial to the
long-term prognosis of CABG, especially the internal mammary artery. The
internal mammary artery was anastomosed to the anterior descending
branch. The radial artery is the second choice, and its long-term
patency is better than vein usage 25, but inferior to
the internal mammary artery 26. However, it takes
longer to obtain arterial grafts than venous grafts. We recommend that
it is necessary to combine the prognosis of patient and the state of the
surgery to decide which type of graft to use. If the long-term prognosis
is poor, a venous graft may be a more appropriate choice. If the tumor
stage is early and the life expectancy is long, total arterial grafts
should be used as far as possible. The preoperative tumor staging of
case 2 indicated that the gastric cancer stage was late and the patient
with acute left heart failure underwent emergency CABG, so the great
saphenous vein was selected as the grafting vessel. The patient of case
5 was younger, had a relatively early preoperative tumor stage, and has
colorectal cancer. Therefore, two arterial grafts from the left internal
mammary artery and radial artery were used.
Except in case 2, the remaining four patients in this study were all
associated with unstable angina. Before surgery, aspirin and clopidogrel
were stopped for seven days according to relevant guidelines, and low
molecular weight heparin was injected subcutaneously for bridging27. Gastric cancer patients were given a nutrient
solution and antiplatelet drugs through the nasal feeding tube on the
first day after surgery. Patients with colorectal cancer were given
intravenous nutrition after surgery, and low molecular weight heparin
was given subcutaneously before eating while oral antiplatelet drugs
were given after eating. By following this principle of discontinuation
and administration, none of the four patients experienced perioperative
severe angina pectoris or severe gastrointestinal bleeding. Case 4
showed signs of gastrointestinal bleeding after antiplatelet drugs were
given following surgery. When the antiplatelet drugs were stopped and
conservative treatment was provided, the patient improved after four
days. No cardiovascular symptoms such as chest tightness or shortness of
breath were seen during the withdrawal. According to our experience, an
indwelling small intestinal nutrition tube placed during the operation
has many advantages; not only can nutrition be supplied through the tube
as soon as possible to promote the early recovery of digestive tract
function, it can also be used to infuse antiplatelet drugs early to
reduce the risk of acute thrombosis of the coronary anastomosis.
We found that the concurrent radical resection of the gastrointestinal
tumor was performed under stable hemodynamics, and the radical resection
of the operation was not affected 28. The follow-up
data also suggest that the overall survival and relapse-free survival
after the concurrent surgeries are equivalent to those of radical
gastrointestinal surgery alone 29. A study of
concurrent surgery for gastric cancer and CABG suggested that the
long-term prognosis depends on the staging status of the gastric cancer
at the time of diagnosis 10.
Anastomotic leakage is a common and serious complication. There has been
no significant difference reported in the proportion of anastomotic
leakage between staged and simultaneous surgeries 15,
30. However, there are some special considerations for concurrent
surgeries, such as the location of the advanced tumor, that influence
whether or not to perform the extended radical operation. If there is
incomplete colonic obstruction before the operation, the surgeons need
to consider the pros and cons to decide whether to anastomose. Tsujiet al . recommended that aggressive concurrent surgical
interventions might bring a benefit to the patients whose survival
periods are expected to be more than six months 10. In
our group of patients, incomplete colonic obstruction was found
preoperatively in case 5, and tumor invasion of a section of the small
intestine was discovered during the operation. Considering the high risk
of the combined operations in the same period, OPCAB + colorectal cancer
resection + affected small intestinal resection + descending colostomy
were performed in the first stage, and then the colon was anastomosed
after the patient’s condition was improved. In addition, wound infection
and treatment are also issues that need to be considered. The incidence
of incision infection and mediastinal infection may be reduced by
closing the thoracic incision first, re-disinfecting strictly and then
performing the gastrointestinal surgery, isolating the thoracoabdominal
incision, and prophylactic use of antibiotics prior to the operation.
Timely reoperation for debridement, colostomy and omentum packing is
conducive to early wound healing and effective control of mediastinal
infection 10, 15.
This study still has some limitations. Firstly, because this study is a
retrospective analysis and the number of included cases is small, there
is a certain bias. Secondly, due to the limitation of the length of
follow-up, the long-term effect of the concurrent surgery needs to be
further followed up and observed. Additional in-depth studies are
necessary to provided more solid evidence.
In summary, for the treatment of patients with gastrointestinal tumors
and severe coronary heart disease, concurrent surgery is being accepted
by a growing number of surgeons. This study provides a useful
exploration of treatment strategies for patients with gastrointestinal
tumors and severe coronary heart disease.