Routine Use of Bilateral Skeletonized Internal Thoracic Artery Grafting

The efficacy of minimally invasive coronary artery bypass grafting (mics cabg) for patients with coronary artery diseases and diabetes: a single center retrospective study

BACKGROUND

conventional coronary artery bypass grafting (CCABG) tends to cause severe complications in patients with comorbid Coronary Artery Diseases (CAD) and diabetes. On the other hand, the Minimally Invasive Cardiac Surgery Coronary Artery Bypass Grafting (MICS CABG) via transthoracic incision is associated with rapid recovery and reduced complications. Adding to the limited literature, this study compares CCABG and MICS CABG in terms of efficacy and safety.

METHODS

Herein, 104 CCABG and MICS CABG cases (52 cases each) were included. The patients were recruited from the Minimally Invasive Cardiac Surgery Center, Anzhen Hospital, between January 2017 and December 2021 and were selected based on the Propensity Score Matching (PSM) model. The key outcomes included All-cause Death, Myocardial Infarction (MI), Cerebrovascular Events, revascularization, Adverse Wound Healing Events and one-year patency of the graft by coronary CTA.

RESULTS

Compared to CCABG, MICS CABG had longer surgical durations [4.25 (1.50) h vs.4.00 (1.13) h, P = 0.028], but showed a reduced intraoperative blood loss [600.00 (400.00) mL vs.700.00 (300.00) mL, P  = 0.032] and a lower secondary incision debridement and suturing rate (5.8% vs.19.2%, P = 0.038). In follow up, no statistically significant differences were found between the two groups in the cumulative Major Adverse Cardiovascular and Cerebrovascular Events (MACCEs) incidence (7.7% vs. 5.9%), all-cause mortality (0 vs. 0), MI incidence (1.9% vs. 2.0%), cerebral apoplexy incidence (5.8% vs. 3.9%), and repeated revascularization incidence (0 vs. 0) (P > 0.05). Additionally, coronary CTA results revealed that the two groups' one-year graft patency (94.2% vs. 90.2%, P = 0.761) showed no statistically significant difference.

CONCLUSION

In patients with comorbid CAD and diabetes, MICS CABG and CCABG had comparable revascularization performances. Moreover, MICS CABG can effectively reduce, if not prevent, poor clinical outcomes/complications, including incision healing, sternal infection and prolonged length of stay in diabetes patients.

Saphenous Vein versus Arterial Graft to the Right System in Left-sided Arterial Revascularization

BACKGROUND

To investigate clinical outcomes of various arterial grafts (AGs) vs. saphenous vein grafts (VGs) to the right coronary system in patients who received left-side bilateral internal thoracic artery revascularization.

METHODS

We compared short- and long-term outcomes of all the patients operated in our center during 1996-2011, who received left-sided bilateral internal thoracic artery (left anterior descending and left circumflex) grafting and either a VG or an AG to the right coronary system.

RESULTS

Of 1691 patients, 983 received a VG and 708 received an AG to the right coronary system: 387 gastroepiploic arteries and 321 internal thoracic artery grafts. The median follow-up was 15.7 ± 0.32 years. For the VG and AG groups, early mortality (1.6% for VG and 1.3% for AG, p=0.55) and other early adverse outcomes did not differ. Long-term (up to 20 years) survival was similar (34.1 +/- 3.4% for VG vs. 36.0 +/-2% for AG, p=0.86). In multivariable analysis, VG to the right coronary artery was not found to be a predictor of inferior survival (hazard ratio: 0.99 95%CI 0.836-1.194, p=0.99). Comparing two propensity matched groups of 349 pairs with a VG or an AG, and accounting for the severity of the right coronary lesion, did not demonstrate differences in early outcome or late survival between the groups.

CONCLUSIONS

Early outcomes and long-term survival were comparable among patients who received left-sided bilateral internal thoracic artery revascularization, between various graft types to the right coronary system.

Patients Submitted to Myocardial Revascularization with the Use of Bilateral Internal Thoracic Arteries: Diabetics vs. Non-Diabetics

INTRODUCTION

Use of bilateral internal thoracic artery (BITA) as graft in coronary artery bypass grafting (CABG) is controversial because it is related to higher in-hospital mortality, incidence of sternal wound-related infection, and an increase in surgical time. The primary objective of this study is to evaluate in-hospital mortality and mortality within 30 days from discharge. The secondary objective is to evaluate the occurrence of deep sternal wound infection in a 90-day follow-up.

METHODS

This is a retrospective review of the medical records of 152 patients undergoing elective CABG with the use of BITA and cardiopulmonary bypass (CPB). These patients were divided into two groups, diabetics and non-diabetics. Patients with acute myocardial infarction and concomitant valvular disease were not included in the sample.

RESULTS

Preoperative characteristics did not show significant differences between the groups, which allowed a comparative analysis. The variables electrocardiography time and aortic clamping time were higher in the diabetic group, with a significant statistical difference (P<0.0001). In-hospital mortality occurred in three patients, and there was no mortality up to 30 days in both groups. There was no significant difference in the primary end point between groups (P=0.56). Deep sternal wound infection was present in only one patient and showed no significant difference in the secondary outcome between groups (P=0.40).

CONCLUSION

We did not observe a higher mortality and occurrence of deep sternal wound infection with the use of BITA in diabetic patients compared to non-diabetics, even with greater CPB and aortic clamping times in diabetics.

Early and late outcomes of single versus bilateral internal thoracic artery revascularization for patients in critical condition

OBJECTIVE

The optimal surgical approach for critically ill patients with complex coronary disease remains uncertain. We compared outcomes of bilateral internal thoracic artery (BITA) versus single ITA (SITA) revascularization in critical patients.

METHODS

We evaluated 394 consecutive critical patients with multi-vessel disease who underwent CABG during 1996-2001. Outcomes measured were early mortality, strokes, myocardial-infarctions, sternal infections, revisions for bleeding, and late survival. The critical preoperative state was acknowledged concisely by one or more of the following: preoperative ventricular tachycardia/fibrillation, aborted sudden cardiac death, or the need for mechanical ventilation or for preoperative insertion of intra-aortic-balloon counter-pulsation.

RESULTS

During the study period, 193 of our patients who underwent SITA and 201 who underwent BITA were in critical condition. The SITA group was older (mean 68.0 vs. 63.3 years, p = 0.001) and higher proportions were females (28.5% vs. 18.9% p = 0.025), after recent-MI (69.9% vs. 57.2% p = 0.009) and with left-main disease (38.3% vs. 49.3% p = .029); the median logistic EuroSCORE was higher (0.2898 vs. 0.1597, p<0.001). No statistically significant differences were observed between the SITA and BITA groups in 30-day mortality; and in rates of early CVA, MI and sternal infections (13.0% vs. 8.5%, p = 0.148; 4.1% vs. 6.0%, p = 0.49; 6.7% vs. 4.5%, p = 0.32 and 2.1% vs. 2.5%, p>0.99, respectively). Long-term survival (median follow-up of 15 years, interquartile-range: 13.57-15) was better in the BITA group (median 14.39 vs. 9.31± 0.9 years, p = 0.001). Propensity-score matching (132 matched pairs) also yielded similar early outcomes and improved long-term survival (median follow-up of 15 years, interquartile-range: 13.56-15) for the BITA group (median 12.49±1.71 vs. 7.63±0.99 years, p = 0.002). In multivariable analysis, BITA revascularization was found to be a predictor for improved survival (hazard-ratio of 0.419, 95%CI 0.23-0.76, p = 0.004).

CONCLUSIONS

This study demonstrated long-term survival benefit for BITA revascularization in patients in a critical pre-operative state who presented for surgical revascularization.

Single versus bilateral internal thoracic artery grafting in patients with low ejection fraction

Coronary artery bypass grafting (CABG) is the standard of care for the treatment of complex coronary artery disease. However, the optimal surgical treatment for patients with reduced left ventricular function with low ejection fraction (EF) is inconclusive. In our center, left-sided coronary grafting with bilateral internal thoracic artery (BITA) is generally the preferred method for surgical revascularization, also for patients with low EF. We compared early and long-term outcomes between BITA grafting and single internal thoracic artery (SITA) grafting in patients with low EF.We evaluated short- and long-term outcomes of all patients who underwent surgical revascularization in our center during 1996 to 2011, according to EF ≥30% and <30%. Univariate and multivariate analyses were performed. In addition, patients who underwent BITA and SITA grafting were matched using propensity score matching.In total, 5337 patients with multivessel disease underwent surgical revascularization during the study period. Of them, 394 had low EF. Among these, 188 underwent SITA revascularization and 206 BITA grafting. Those who underwent SITA were more likely to have comorbidities such as chronic obstructive pulmonary disease, diabetes, congestive heart failure, chronic renal failure, and a critical preoperative condition including preoperative intra-aortic balloon pump insertion.Statistically significant differences were not observed between the SITA and BITA groups in 30-day mortality (8.5% vs 6.8%, P = .55), sternal wound infection (2.7% vs 1.0%, P = .27), stroke (3.7% vs 6.3%, P = .24), and perioperative myocardial infarction (5.9% vs 2.9%, P = .15). Long-term survival (median follow up of 14 years, interquartile range, 11.2-18.9) was also similar between the groups. Propensity score matching (129 matched pairs) yielded similar early and long-term outcomes for the groups.This study did not demonstrate any clinical benefit for BITA compared with SITA revascularization in individuals with low EF.

The use of both internal thoracic arteries for coronary revascularization increases the estimate of post-operative lower limb ischemia in patients with peripheral artery disease

Background

Patients with a history of peripheral arterial disease (PAD) undergoing coronary artery bypass grafting (CABG) exhibit higher rates of complications. There are conflicting data on the survival benefits for bilateral thoracic artery (BITA) grafting compared with left internal thoracic artery (LITA) CABG in patients with PAD. The aim of the study was to explore the influence of the use of BITA grafts vs. LITA for CABG on post-operative acute lower limb ischemia (ALLI) and main post-operative complications in patients with concomitant PAD.

Methods

We used a propensity-score (PS) based analysis to compare outcomes between the two surgical procedures, BITA and LITA. The inverse probability of treatment weighting PS technique was applied to adjust for pre- and intra-operative confounders, and to get optimal balancing of the pre-operative data. The primary outcome was the estimate of postoperative ALLI. Secondary outcomes included overall death and death of cardiac causes within 30 days of surgery, stroke and acute kidney disease (AKD).

Results

The study population consisted of 1961 patients. The LITA procedure was performed in 1768 patients whereas 193 patients underwent a BITA technique. The estimate of ALLI was 14% higher in the BITA compared to the LITA (p < 0.001) group. Thirty-day mortality, cardiac death, occurrence of stroke and AKI did not differ significantly between the groups.

Conclusions

The use of both ITAs led to a significant increase in ALLI. This result was most likely caused by the complete disruption of the ITA collateral providing additional blood supply to the lower extremities. Based on our data, BITA should be used with extreme caution in PAD patients. Further research on this topic is necessary to confirm our findings.

Bilateral internal thoracic artery grafting in patients with left main disease: a single-center experience

OBJECTIVE

We compared early and long-term outcomes between bilateral internal thoracic artery (BITA) grafting and single internal thoracic artery (SITA) grafting in patients with LM disease.

METHODS

We evaluated the outcomes of all patients with LM disease who underwent revascularization in our center during 1996-2011. Variables that were adjusted for in a multivariate analysis and in propensity matching included age, sex, comorbid diseases, repeat operation, the number of diseased vessels, other conduits used, the use of sequential grafting, the number of grafts constructed, and the operative era (1996-2000 vs. 2001-2011).

RESULTS

In total, 949 patients with LM disease underwent BITA grafting and 564 underwent SITA grafting during the study period. SITA patients were more often female and more likely to have comorbidities such as chronic obstructive pulmonary disease, ejection fraction <30%, recent myocardial infarction, diabetes, congestive heart failure, chronic renal failure, and peripheral vascular disease, and to have undergone an emergency operation. We found no statistically significant difference between the SITA and BITA groups in 30-day mortality (4.8% vs. 3.3%, P = 0.136), sternal wound infection (2.0% vs. 2.4%, P = 0.548), and stroke (3.2% vs. 4.4%, P = 0.234). BITA patients had improved long-term survival (70.1% vs. 52.0% p<0.001), median follow-up of 15 years. In multivariate analysis, after propensity score matching (477 matched pairs), this finding was not statistically significant (P = 0.135).

CONCLUSION

This study did not demonstrate a clear benefit of BITA grafts among patients with LM disease.

Are two internal thoracic grafts better than one in patients with peripheral vascular disease?

BACKGROUND

The use of two bilateral internal thoracic artery grafting (BITA) was shown to lead to survival benefit. However, operators are reluctant to use BITA with peripheral vascular disease (PVD) because of concerns of increased rates of sternal wound infection and lack of studies supporting survival benefit compared with single internal thoracic artery (SITA) grafting. The aim of this study is to compare outcome BITA grafting versus of SITA and vein grafts in PVD patients.

PATIENTS AND METHODS

Six hundred and twenty-one PVD patients who underwent BITA between 1996 and 2011 were compared with 372 patients who underwent SITA.

RESULTS

SITA patients were older and more likely more likely to have comorbidities (female, insulin-dependent diabetes, chronic obstructive lung disease, congestive heart failure, previous coronary artery bypass grafting, renal insufficiency, cerebrovascular disease, and emergency operation). Operative mortality (5.1 vs. 4.5%, in the SITA and BITA, respectively, P=0.758), rate of sternal wound infection (5.1 vs. 3.9%, P=0.421), and strokes (4.8 vs. 7.4%, P=0.141) were not significantly different between groups. BITA patients did not have significantly better 10-year survival (52.6 vs. 45.9%, P=0.087) and after propensity score matching (302 well-matched pairs), BITA was not associated with improved survival (hazard ratio: 0.902; 95% confidence interval: 0.742-1.283; P=0.784) (Cox model).

CONCLUSION

The routine use of BITA versus SITA in PVD patients does not improve long-term survival. Selective use of BITA in lower risk patients might unmask the benefits of BITA.

A simple-to-use nomogram to predict long term survival of patients undergoing coronary artery bypass grafting (CABG) using bilateral internal thoracic artery grafting technique

BACKGROUND

Several risk scores have been created to predict long term mortality after coronary artery bypass grafting (CABG). Several studies demonstrated a reduction in long-term mortality following bilateral internal thoracic arteries (BITA) compared to single internal thoracic artery. However, these prediction models usually referred to long term survival as survival of up to 5 years. Moreover, none of these models were built specifically for operation incorporating BITA grafting.

METHODS

A historical cohort study of all patients who underwent isolated BITA grafting between 1996 and 2011 at Tel-Aviv Sourasky medical center, a tertiary referral university affiliated medical center with a 24-bed cardio-thoracic surgery department. Study population (N = 2,935) was randomly divided into 2 groups: learning group which was used to build the prediction model and validation group. Cox regression was used to predict death using pre-procedural risk factors (demographic data, patient comorbidities, cardiac characteristics and patient's status). The accuracy (discrimination and calibration) of the prediction model was evaluated.

METHODS AND FINDINGS

The learning (1,468 patients) and validation (1,467 patients) groups had similar preoperative characteristics and similar survival. Older age, diabetes mellitus, chronic obstructive lung disease, congestive heart failure, chronic renal failure, old MI, ejection fraction ≤30%, pre-operative use of intra-aortic balloon, and peripheral vascular disease, were significant predictors of mortality and were used to build the prediction model. The area under the ROC curves for 5, 10, and 15-year survival ranged between 0.742 and 0.762 for the learning group and between 0.766 and 0.770 for the validation group. The prediction model showed good calibration performance in both groups. A nomogram was built in order to introduce a simple-to-use tool for prediction of 5, 10, and 15-year survival.

CONCLUSIONS

A simple-to-use validated model can be used for a prediction of 5, 10, and 15-year mortality after CABG using the BITA grafting technique.

Are two internal thoracic grafts better than one in patients with chronic obstructive lung disease? Analysis of 387 cases between 1996-2011

Objectives

Bilateral internal thoracic artery (ITA) grafting is associated with improved survival. However, potential survival benefit of using two ITA`s in patients with chronic lung disease (CLD) is questionable due to their increased risk of sternal wound infection (SWI) compared to operations incorporating single ITA (SITA). The purpose of this study is to compare early and long-term outcome of bilateral internal thoracic artery (BITA) grafting to that of grafting with single internal thoracic grafts and vein grafts or radial artery (SITA) in CLD patients with multi-vessels coronary disease.

Methods

One hundred and forty eight CLD patients who underwent BITA between 1996 and 2011 were compared with 239 who underwent SITA at the same period.

Results

SITA patients were more often female, more likely to have insulin treated diabetes (DM), DM with end organ damage, neurologic dysfunction and unstable angina.

Despite of the difference in preoperative characteristics, early mortality (5.4% vs. 5.4%, in the SITA and BITA respectively, p = 0 < .999) and occurrences of SWI (6.3% vs 9.5%, p = 0.320) and strokes (3.8% vs 5.4%,p = 0.611) were not significantly different between groups. BITA patients did not have better Kaplan-Meier 10 year survival (52.8% vs. 42.6%, p = 0.088) and after matching, BITA and SITA had similar adjusted survival (HR 0.983[95%CI 0.755–1.280] p = 0.901) (cox model).

Conclusion

Our study results suggest that in patients with CLD, the choice of BITA grafting technique did not provide survival benefit compared to SITA with other conduits.

Should Bilateral Internal Thoracic Artery Grafting Be Used in Patients After Recent Myocardial Infarction?

Background

Bilateral internal thoracic artery grafting (BITA) is associated with improved survival. However, surgeons do not commonly use BITA in patients after myocardial infarction (MI) because survival is good with single internal thoracic artery grafting (SITA). We aimed to compare the outcomes of BITA with those of SITA and other approaches in patients with multivessel disease after recent MI.

Methods and Results

In total, 938 patients with recent MI (<3 months) who underwent BITA between 1996 and 2011 were compared with 682 who underwent SITA. SITA patients were older and more likely to have comorbidities (diabetes mellitus, chronic obstructive pulmonary disease, chronic renal failure, peripheral vascular disease), to be female, and to have had a previous MI. Acute MI and 3‐vessel disease were more prevalent in the BITA group. Operative mortality of BITA patients was lower (3.0% versus 5.8%, P=0.01), and sternal infections and strokes were similar. Median follow‐up was 15.21 years (range: 0–21.25 years). Survival of BITA patients was better (70.3% versus 52.5%, P<0.001). Propensity score matching was used to account for differences in preoperative characteristics between groups. Overall, 551 matched pairs had similar preoperative characteristics. BITA was a predictor of better survival in the matched groups (hazard ratio: 0.679; P=0.002; Cox model). Adjusted survival of emergency BITA and SITA patients was similar (hazard ratio: 0.883; P=0.447); however, in the nonemergency group, BITA was a predictor of better survival (hazard ratio: 0.790; P=0.009; Cox model).

Conclusions

This study suggests that survival is better with BITA compared with SITA in nonemergency cases after recent MI, with proper patient selection.

Liberal bilateral internal thoracic artery use in people with diabetes neutralizes the negative impact of insulin-requiring status

AIMS

Bilateral internal thoracic artery (BITA) grafts are underused in insulin-dependent diabetic patients because of increased risk of postoperative complications. The impact of the insulin-requiring status on outcomes after routine BITA grafting was investigated in this retrospective study.

METHODS

Skeletonized BITA grafts were used in 3228 (71.6%) of 4508 consecutive patients having multivessel coronary disease who underwent isolated coronary bypass surgery at the authors' institution from January 1999 to August 2015. Among these BITA patients, diabetes mellitus and the insulin-requiring status were present in 972 (30.1%) and 237 (7.3%) cases, respectively. After the one-to-one propensity score-matching, 215 pairs of insulin-dependent/noninsulin-dependent people with diabetes were compared as the postoperative outcomes. The operative risk was calculated for each patient according to the logistic European System for Cardiac Operative Risk Evaluation (logistic EuroSCORE).

RESULTS

As expected, insulin-dependent people with diabetes had higher risk profiles than noninsulin-dependent people with diabetes (median logistic EuroSCORE, 4.1 vs. 3.5%, P = 0.086). However, there were no differences in in-hospital mortality both in unmatched and propensity score-matched series (2.5 vs. 2%, P = 0.65 and 2.8 vs. 1.9%, P = 0.52, respectively). In propensity score-matched pairs, only prolonged invasive ventilation (P = 0.0039) and deep sternal wound infection (P = 0.071) were more frequent in insulin-dependent people with diabetes. No differences were found as the late outcomes.

CONCLUSION

In diabetic patients, the insulin-requiring status is by itself a risk factor neither for in-hospital death nor for poor late outcomes after routine BITA grafting. Only the risk of prolonged invasive ventilation and deep sternal wound infection are increased early after surgery.

Coronary artery bypass surgery in diabetic patients - risk factors for sternal wound infections

The incidence of sternal wound infections (SWI) after coronary artery bypass surgery (CABG) as reported worldwide is low. However, it is associated with significant increase of postoperative mortality and treatment costs. The major risk factors discussed are diabetes mellitus and bilateral IMA harvesting of the internal mammary artery. This study analyses data of 590 patients receiving CABG concerning the risk factors for SWI. Sternal wound infections occur significantly more often in diabetic patients, one crucial and significant additional risk factor is obesity.

The Impact of Diabetes on Early Outcomes after Routine Bilateral Internal Thoracic Artery Grafting

BACKGROUND

Increased risk of postoperative complications limits use of bilateral internal thoracic artery (BITA) grafting in diabetic patients. The authors' experience in routine BITA grafting was reviewed to investigate the impact of diabetes on early outcomes.

METHODS

Among the 4508 consecutive patients with multivessel coronary artery disease who underwent isolated coronary bypass surgery from January 1999 throughout August 2015, skeletonised BITA grafts were used in 3228 (71.6%) patients, 972 diabetic and 2256 non-diabetic. After one-to-one propensity score (PS)-matched analysis, 819 pairs of diabetic/non-diabetic patients were compared for postoperative outcomes. The operative risk was calculated for each patient according to the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II).

RESULTS

Although diabetic had higher risk profiles than non-diabetic patients both in unmatched (EuroSCORE II: 5.3±7.3% vs. 3±4.2%, p<0.0001) and PS-matched series (EuroSCORE II: 5.1±7.1% vs. 3.6±4.3%, p<0.0001), there were no differences in hospital mortality (2.2% vs. 1.8%, p=0.52 and 2.1% vs. 2.3%, p=0.74, respectively). In PS-matched pairs, the use of adrenergic agonists (p=0.03), postoperative bleeding (p=0.0055) and deep incisional sternal wound infection (p=0.0018) were more frequent in diabetic patients who had a mean of longer hospital stays (p=0.023).

CONCLUSIONS

Bilateral internal thoracic artery grafting may be routinely performed even in diabetic patients despite higher risk profiles. Increased postoperative complications prolong hospital stay but do not impact on early mortality.

Pure Bilateral Internal Thoracic Artery Grafting in Diabetic Patients With Triple-Vessel Disease

BACKGROUND

Despite the documented superior long-term patency of bilateral internal thoracic artery (BITA) grafting, use of BITAs remains low, especially in diabetic patients. We analyzed the results of pure BITA grafting to determine whether the potential survival advantage outweighs the risk of wound infection in diabetic patients.

METHODS

We performed a retrospective analysis of 791 consecutive patients (389 diabetic, 402 nondiabetic) with triple-vessel disease who underwent off-pump coronary artery bypass using only skeletonized BITAs from 2001 to 2010. We used propensity score matching to match 315 nondiabetic patients with diabetic patients.

RESULTS

The groups did not differ significantly regarding 10-year survival (diabetic, 84.2% ± 4.5%; nondiabetic, 80.8% ± 4.7%; p = 0.828) or freedom from major adverse cardiovascular events (diabetic, 73.5% ± 5.2%; nondiabetic, 71.8% ± 5.3%; p = 0.431). Diabetes was not predictive of deep sternal infection (odds ratio, 1.11; 95% confidence interval, 0.23 to 5.31; p = 0.895). Results of stratified competing risks regression analysis showed that the risk of target vessel revascularization in diabetic patients was similar to that of nondiabetic patients (subdistribution hazard ratio, 0.67; 95% confidence interval, 0.16 to 2.80; p = 0.585).

CONCLUSIONS

Off-pump coronary artery bypass grafting using pure BITAs produced excellent clinical outcomes in both diabetic and nondiabetic patients. This strategy did not increase the incidence of deep sternal infection in diabetic patients. We recommend BITA grafting, which has proven long-term patency, as a strategy of choice in diabetic patients.

Coronary artery disease and diabetes mellitus

Diabetes mellitus (DM) is a major risk factor for cardiovascular disease. Near-normal glycemic control does not reduce cardiovascular events. For many patients with 1- or 2-vessel coronary artery disease, there is little benefit from any revascularization procedure over optimal medical therapy. For multivessel coronary disease, randomized trials demonstrated the superiority of coronary artery bypass grafting over multivessel percutaneous coronary intervention in patients with treated DM. However, selection of the optimal myocardial revascularization strategy requires a multidisciplinary team approach ('heart team'). This review summarizes the current evidence regarding the effectiveness of various medical therapies and revascularization strategies in patients with DM.

Bilateral internal thoracic artery grafting for peripheral arterial disease patients

BACKGROUND

Peripheral arterial disease (PAD) is known to have a poor prognosis. Some reports have also described poor late results after coronary artery bypass grafting (CABG). However, there have been few reports about whether bilateral internal thoracic artery grafting improves the long-term survival of PAD patients after CABG. We performed this study to clarify whether or not this is the case.

METHODS

One hundred and thirty-six PAD patients who underwent elective CABG with two or more grafts were enrolled in this study. Patients were divided into two groups, 71 patients in the bilateral internal thoracic artery (BITA) group and 65 patients in the single internal thoracic artery (SITA) group. The maximum follow-up period was 19 years, with a mean of 5.7 ± 4.4 years.

RESULTS

We investigated the long-term results based on three factors; survival, freedom from cardiac death, and freedom from cardiac events. The 3-, 5- and 10-year survival rates in the BITA group were 83.0, 74.2, and 43.1%, respectively. And those in the SITA group were 79.4, 67.7, and 32.3%, respectively. There were no significant differences between the two groups (p = 0.5843). There were also no statistically significant differences between the two groups in terms of the freedom from cardiac death (p = 0.8589) or in the freedom from cardiac events (p = 0.9445).

CONCLUSION

No long-term advantage was observed for CABG with BITA in comparison to SITA alone in patients with PAD.

Long-term outcomes of coronary artery bypass grafting patients supported preoperatively with an intra-aortic balloon pump

OBJECTIVE

Most studies describing the outcome of coronary artery bypass grafting patients supported preoperatively with an intra-aortic balloon pump (IABP) have reported early results. The purpose of our study was to evaluate the early and long-term results.

METHODS

Of 2658 isolated coronary artery bypass grafting procedures performed from 1996 to 2001, 215 were supported preoperatively with an IABP. The indications for IABP insertion were cardiogenic shock in 18 (8.4%), acute evolving myocardial infarction in 38 (17.7%), clinical instability in 84 (39.1%), and critical coronary lesions in 75 (34.9%).

RESULTS

Operative mortality was 12.6%. The mortality of the cardiogenic shock patients was greater (22.2%; P=.174). Logistic regression analysis showed patient age (odds ratio, 1.057; 95% confidence interval, 1.010-1.108) and cardiopulmonary bypass (CPB) time (odds ratio, 1.020; 95% confidence interval, 1.008-1.031) were associated with increased operative mortality. An increased number of bypass grafts had a protective effect (odds ratio, 0.241; 95% confidence interval, 0.113-0.515). The actual early mortality was lower than the logistic EuroSCORE calculated mortality (12.6% vs 32.8%, P<.0001). The mean follow-up was 8±4 years. The Kaplan-Meier 10-year survival was 49%. The Cox adjusted overall (early and late) survival and major adverse cardiac events-free survival of the different IABP subgroups was similar. Cox analyses showed peripheral vascular disease, off-pump coronary artery bypass surgery, age, CPB time, female gender, and fewer bypass grafts were associated with decreased survival.

CONCLUSIONS

In patients supported preoperatively with an IABP, better early and long-term results were strongly related to younger age, a shorter CPB time, and a greater number of bypass grafts. Avoiding the use of CPB (off pump) in these emergency cases is not recommended.

Outcomes of off-pump coronary bypass grafting with the bilateral internal thoracic artery for left ventricular dysfunction

This study evaluated the outcomes of off-pump coronary artery bypass surgery (OPCAB) with severe left ventricular dysfunction using composite bilateral internal thoracic artery grafting. From January 2001 to December 2008, 1,842 patients underwent primary isolated OPCAB with composite bilateral internal thoracic artery grafting. A total of 131 of these patients were diagnosed with a severely depressed preoperative left ventricle ejection fraction (LVEF) (≤ 0.35). These patient outcomes were compared with the outcomes of 830 patients that had mildly or moderately depressed LVEF (0.36 to 0.59) and 881 patients with normal LVEF (>0.6). The early mortality for patients with severe LVEF was 2.3%. The 3-yr and 7-yr survival rate for patients with severe LV dysfunction was 86.0% and 82.8%, respectively. Multivariate analysis showed that severe LV dysfunction EF increased the risk of all-cause death (P=0.012; hazard ratio [HR],2.14; 95% confidence interval [CI],1.19-3.88) and the risk of cardiac-related death (P=0.008; HR,3.38; 95% CI, 1.37-8.341). The study identified positive surgical outcomes of OPCAB, although severe LVEF was associated with two-fold increase in mortality risk compared with patients who had normal LVEF.

Incidence and risk factors of sternal wound infection at site of incision after open-heart surgery

OBJECTIVE

To identify the incidence of sternal wound infection and the risk factors before, during and after open-heart surgery in an Iranian critical care unit.

METHOD

A descriptive, analytic study investigating all open-heart surgery patients from March 2010 to March 2011, in terms of the incidence of sternal wound infection and the risk factors before, during, and after surgery. Patients were examined for signs of infection at the site of surgical incision on presentation to the ward, daily during their stay, and on discharge. The same investigator reviewed all wounds, every day.

RESULTS

The incidence of sternal wound infection was found to be 10%. Multivariate regression analysis identified the following risk factors: diabetes (OR: 0.439; 95%CI: 0.21-0.95; p=0.04), age (OR: 1.033; 95%CI: 1.003-1.064; p=0.03), hyperlipidaemia (OR: 1.008; 95%CI: 1.005-1.011; p<0.001), history of respiratory disorders ([COPD] OR: 2.952; 95%CI: 1.3-6.4; p=0.007), female gender (OR: 2.06; 95%CI: 1.40-3.03; p<0.008), and history of addiction to opiates (OR: 2.33; 95%CI: 1.56-3.49; p<0.006).

CONCLUSION

This study found a high rate of surgical sternal wound infection in open-heart surgery patients in an Iranian critical care unit, suggesting that the medical and care-giving team in the cardiac intensive care unit need further education.

DECLARATION OF INTEREST

There were no external sources of funding for this study. The authors have no conflicts of interest to declare.

NUMERICAL INVESTIGATION OF PULSATILE FLOW IN AN S-TYPE BYPASS GRAFT

Intimal hyperplasia developed at the end-to-side anastomosis of artery bypass is closely related to unphysiological hemodynamics. The helical flow as a normal physiological phenomenon in arteries is beneficial to endothelial damage repair. To deeply understand the physiological flow properties in a S-type bypass (StB) graft, four end-to-side bypass models including 30°, 45°, 60° conventional bypasses and a 45° StB were compared numerically under physiological pulsatile flow. The results showed that strong helical flow was observed at the distal anastomosis of StB. The distribution of hemodynamic parameters such as helicity, average wall shear stress and oscillating shear index, etc. were significantly improved at the S-type anastomosis as compared with those of three conventional models. The area-averaged normalized helicity in StB reached maxima at the moments of maximum flow rate and systolic deceleration. The hemodynamic performance in a 45° StB was improved as compared with a 30° conventional model. It is concluded that large StB anastomosis angle can be taken to achieve good hemodynamic performance while much smaller anastomosis angle has to be adopted for conventional bypass. As such, a S-type anastomosis should be a feasible choice of clinical artery bypass grafting due to its significant improvement in hemodynamic performance.

Role of CABG in the management of obstructive coronary arterial disease in patients with diabetes mellitus

Multiple studies have shown that diabetes mellitus (DM) can affect the efficacy of revascularization therapies and subsequent clinical outcomes. Selection of the appropriate myocardial revascularization strategy is critically important in the setting of multivessel coronary disease. Optimal medical therapy is an appropriate first-line strategy in patients with DM and mild symptoms. When medical therapy does not adequately control symptoms, revascularization with either PCI or CABG may be used. In patients with treated DM, moderate to severe symptoms and complex multivessel coronary disease, coronary artery bypass graft surgery provides better survival, fewer recurrent infarctions and greater freedom from re-intervention. Decisions regarding revascularization in patients with DM must take into account multiple factors and as such require a multidisciplinary team approach ('heart team').

Is diabetic nephropathy a predicted risk factor?--Kaplan-Meier and multivariate analysis of confounding risk factors in off-pump coronary artery bypass grafting for chronic dialysis patients

BACKGROUND

The purpose of this study was to investigate the preoperative risk factors of performing off-pump coronary artery bypass grafting (OPCAB) in patients on chronic dialysis.

METHODS AND RESULTS

The 41 consecutive patients on chronic dialysis who underwent OPCAB from February 2000 to April 2006 at the National Cardiovascular Center were studied retrospectively. Of them, 29 had diabetic nephropathy (DN group) and the remaining 12 did not (NDN group). There were significant differences in the duration of dialysis before surgery (9.1 +/-7.5 years in NDN vs 4.2 +/-5.5 years in DN, P=0.028) and low cardiac function (left ventricular ejection fraction <30%), which was recognized only in the DN group (7/29, P=0.048). The early mortality rate was 6.9% (2/29) in the DN group and 16.7% (2/12) in the NDN group (P=0.349). The actuarial survival rates in the DN group were 85% at 1 year, 45% at 3 years, and 30% at 5 years, whereas in the NDN group they were 71%, 49%, and 49%, respectively (P=0.789). arteriosclerosis obliterans (ASO) and age (>65 YEARS) were independent risk factors of late death.

CONCLUSIONS

For patients on chronic dialysis ASO and aging were predicted risk factors for OPCAB, whereas diabetic nephropathy was not.