Bilateral Internal Thoracic Artery Grafting: Is It Reasonable in Octogenarians?

Meta-analysis of BITA versus SITA grafting in diabetic patients: evidence from propensity score-matched studies

BACKGROUND

It has been demonstrated that the use of bilateral internal thoracic artery (BITA) grafting in coronary artery bypass grafting (CABG) improves long-term survival in comparison to the use of a single internal thoracic artery (SITA) graft. However, the optimal transplantation technique for diabetic patients remains undetermined. The purpose of this meta-analysis was to compare the effectiveness and safety of BITA and SITA CABG in diabetic patients.

METHODS

A comprehensive search of Google Scholar, Science Direct, and PubMed was conducted for studies with propensity score-matched comparing between BITA and SITA grafting in diabetic patients. The main goal was to know mid- to long-term mortality, and the supplementary results included incidence of deep sternal wound infection, 30-day mortality, and incidence of reoperation due to hemorrhage.

RESULTS

The meta-analysis included 11 studies involving 3762 diabetic patients with matched propensity scores. Compared to SITA grafting, BITA grafting was associated with a significant reduction in long-term mortality (HR 0.78; 95% CI 0.67-0.91), P = 0.03, I2 = 54%. There were no significant differences between the two groups in terms of 30-day mortality, reoperation for bleeding, cerebrovascular accident, or renal failure.

CONCLUSIONS

BITA grafting appears to provide better overall survival than SITA grafting in patients with diabetes. However, using BITA grafting is associated with a greater risk of deep sternal wound infection. These findings may help guide the choice of grafting technique in diabetic patients undergoing CABG.

Impact of Graft Strategies on the Outcome of Octogenarians Undergoing Coronary Artery Bypass Grafting

PURPOSE

To analyse the outcome of coronary artery bypass grafting (CABG) in octogenarians with coronary multivessel disease and the impact of different graft strategies and other factors.

METHODS

Out of 1654 patients with multivessel disease who underwent CABG at our institution between January 2014 and March 2020, we investigated 225 consecutive patients with a median age of 82.1 years for survival prediction and need for coronary reintervention; a detailed outcome analysis was performed.

RESULTS

At mean follow-up of 3.3 years, the overall survival was 76.4%. An indication for emergency operation (p = 0.002), age (p <0.001), chronic pulmonary disease (p = 0.024), and reduced renal or ventricular function (p <0.001) had the highest impact on limited survival. The combination outcome of survival and coronary reintervention was 1.7-fold improved (p = 0.024) after use of the bilateral internal thoracic artery (BITA) (66.2%). Off-pump CABG (12%) revealed no impact on survival. Smokers showed a poorer outcome (p = 0.004). The logistic European System for Cardiac Operative Risk Evaluation was highly effective for evaluating long-term outcomes (p <0.001).

CONCLUSIONS

BITA grafting normalizes survival and reveals a better outcome in octogenarians with multivessel disease. However, patients at risk of poorer survival were operated under emergency conditions and those with pulmonary disease and reduced ventricular or renal function.

Meta-Analysis of Bilateral Versus Single Internal Thoracic Artery Grafting in Patients ≥70 Years of Age

The optimal choice of graft material in patients ≥70 years of age undergoing coronary artery bypass grafting remains unknown. A systematic review of literature was conducted by searching PubMed, Embase, Web of Science, and Cochrane Library databases for original publications that compared bilateral internal thoracic artery (BITA) grafting with single internal thoracic artery grafting in patients ≥70 years of age. Data were extracted by 2 independent investigators and meta-analyzed with the use of random effects. A total of 10 studies, including 11,185 patients, met the inclusion criteria. No differences in early mortality and morbidity, with the exemption of sternal wound complications which were more frequently observed in the BITA group (odds ratio 1.72, 95% 1.00 to 2.96 confidence interval [CI], p = 0.05; propensity score-matched population odds ratio 1.58, 95% CI 1.09 to 2.29, p = 0.02), were observed. Overall survival was superior in the overall patient population (hazard ratio [HR] 0.76, 95% CI 0.66 to 0.86, p <0.001), after applying a blanking period of 3 months to the overall patient population (HR 0.77, 95% CI 0.64 to 0.92, p = 0.005) as well as in the matched population (HR 0.72, 95% CI 0.58 to 0.89, p = 0.002); in all cases, a benefit was readily seen within a few years after surgery. The difference in freedom from major adverse cardiac and cerebrovascular events failed to reach statistical significance (overall patient population HR 0.55, 95% CI 0.27 to 1.13, p = 0.10; matched population HR 0.52, 95% CI 0.23 to 1.16, p = 0.11). In conclusion, BITA grafting can be safely performed in patients ≥70 years of age as late clinical benefits are expected to manifest themselves readily within a few years after surgery.

Effect of bilateral internal thoracic artery harvesting on deep sternal wound infection in diabetic patients: Review of literature

Instead of its documented superiority of patency and long-term outcomes, the bilateral internal thoracic artery grafts are underused in the general population, and its use is controversial and debatable in diabetic patients due to long surgery duration, post-surgical bleeding, and sternal wound complications such as sternal wound infection, mediastinitis, and sternal wound dehiscence. This review article is particularly focused on deep sternal wound infection (DSWI) of bilateral internal thoracic artery (BITA) grafts in diabetic patients with comparison to single internal thoracic artery (SITA) graft.

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Bilateral internal thoracic artery grafting is superior to single internal thoracic artery grafting in terms of outcomes.

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Bilateral internal thoracic artery grafting is underused, especially in diabetic patients.

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The risk of DSWI in skeletonized BITA grafting in diabetic patients is almost similar to SITA grafting.

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Skeletonized BITA grafting should be encouraged in selected diabetic patients.

Short-term results of bilateral internal mammary arterial grafting for patients aged 60-75 years - a retrospective study

BACKGROUND

Bilateral internal mammary artery (BIMA) grafting has a good long-term survival rate and graft patency rate, but it is only recommended in young patients due to its high technical requirements and high incidence of sternal complications. Previous studies indicated that BIMA grafting has a significant benefit in patients aged 50-59 years, but this benefit does not extend to patients aged > 60 years. Thus, this study was designed to analyse the immediate artery graft function, short-term (3 months) results, and experience in preventing sternal complications for BIMA grafting in elderly patients (60-75 years old).

METHODS

Clinical records and echocardiographic and coronary artery computed tomography angiography data of 155 patients who underwent BIMA grafting for coronary artery disease between 2015 and 2017 in our hospital were analysed retrospectively to summarise the operative experience and short-term (3 months) results. Patients were divided into two groups: Group A (n = 95), aged < 60 years and Group B (n = 60), aged 60-75 years. The operation time, aortic clamp time, and cardiopulmonary bypass time of these two groups were compared to analyse the operation difficulty and the flow and pulsatility index were compared to analyse the immediate artery graft function. The left ventricular end-diastolic dimension (LVEDD) and left ventricular ejection fraction (LVEF) of these two groups were compared to analyse heart function.

RESULTS

There were no significant differences in the operation time, aortic clamp time, and cardiopulmonary bypass time as well as the flow and pulsatility index between these two groups (P > 0.05). There was no significant difference in the incidence of sternal wound complications, graft occlusion, and other common complications 3 months post-BIMA grafting between these two groups (P > 0.05). Furthermore, there was no significant difference in LVEDD and LVEF between the groups 3 months post-operation (P > 0.05).

CONCLUSIONS

BIMA grafting was safe and effective for older patients (60-75 years). Similar to younger patients (< 60 years), BIMA grafting in elderly patients (60-75 years) can also achieve a satisfactory short-term (3 months) result. Thus, advanced age (60-75 years) should not be a contraindication for BIMA grafting.

Is Bilateral Internal Mammary Arterial Grafting Beneficial for Patients Aged 75 Years or Older?

BACKGROUND

Although bilateral internal mammary artery (BIMA) grafting is performed with increasing regularity in elderly patients, whether it is truly beneficial, and therefore indicated, in these patients remains uncertain. We retrospectively investigated early and late outcomes of BIMA grafting in patients aged ≥75 years.

METHODS AND RESULTS

We identified 460 patients aged ≥75 years from among 2,618 patients who underwent either single internal mammary artery (SIMA) grafting (n=293) or BIMA grafting (n=107). Early outcomes did not differ between the SIMA and BIMA patients (30-day mortality: 1.7% vs. 0%, P=0.39; sternal wound infection: 1.0% vs. 4.7%; P=0.057). Late outcomes, 10-year survival in particular, were improved in the BIMA group (36.6% vs. 48.1%, P=0.033). In the analysis of the results in propensity score-matched groups (196 patients in the SIMA group, 98 patients in the BIMA group), improved 10-year survival was documented in the BIMA group (34.8% vs. 47.6%, P=0.030). Cox proportional regression analysis showed SIMA usage (non-use of BIMA) to be a predictor for late mortality (hazard ratio: 0.65, 95% confidence interval: 0.43-0.98, P=0.042). We further compared outcomes between the total non-elderly patients (n=2,158) and total elderly patients (n=460). BIMA usage was similar, as was 30-day mortality (1.0% vs. 1.3%, respectively).

CONCLUSIONS

A survival advantage, with no increase in early mortality, can be expected from BIMA grafting in patients aged ≥75 years. (Circ J 2016; 80: 1756-1763).