Sequential composite BIMA grafting for 3v-CAD: factors that predict successful outcome of the one-inflow and two-inflow revascularization techniques

OBJECTIVE

The effect of one-inflow and two-inflow coronary surgical revascularization techniques inclosing skeletonized double mammary artery (BIMA) as T-graft on outcome is studied.

METHODS

Early ad mid-term outcome of complete BIMA revascularization (C-T-BIMA) versus left-sided BIMA with right-sided aorto-coronary bypass (L-T-BIMA + R-CABG) is quantified and analyzed by multivariate logistic regression, Cox-regression, and Kaplan-Meier analysis in a series of 204 consecutive patients treated for triple-vessel coronary disease (3v-CAD).

RESULTS

The L-T-BIMA + R-CABG technique (n = 104) enables higher number of total (4.02 ± 0.87 vs. 3.71 ± 0.69, p = 0.015) and right-sided (1.21 ± 0.43 vs. 1.02 ± 0.32, p = 0.001) coronary anastomoses, improves total bypass flow (125.88 ± 92.41 vs. 82.50 ± 49.26 ml, p < 0.0001) and bypass flow/anastomosis (31.83 ± 23.9 vs.22.77 ± 14.23, p = 0.001), and enhances completeness of revascularization (84% vs.69%, p = 0.014) compared to C-T-BIMA strategy (n = 100), respectively. Although the incidence of MACCE was comparable in the two groups (8% vs.1.2%, p = 0.055), the progression of functional mitral regurgitation (FMR) was significantly lower after L-T-BIMA + R-CABG, then after C-T-BIMA (47% vs.64%, p = 0.017). The use of C-T-BIMA-technique (HR = 4.2, p = 0.01) and preoperative RCA occlusion (HR = 3.006, p = 0.023) predicted FMR progression, whereas L-T-Graft + R-CABG technique protected against it (X2 = 14.04, p < 0.0001) independent of the anatomic and clinical complexity (Syntax score I: HR = 16.2, p = 0.156, Syntax score II: HR = 1.901, p = 0.751), of early- (0.96% vs.2%, p = 0.617) and mid-term mortality (5.8% vs.4%, p = 0.748) when compared to C-T-BIMA, respectively.

CONCLUSIONS

The two-inflow coronary revascularization by L-T-BIMA + R-CABG better protects against FMR progression without increasing MACCE and mortality. Older patients with RCA occlusion and reduced LV-EF benefit most from the two-inflow L-T-BIMA + R-CABG technique. Younger 3v-CAD patients with normal LV-EF can preferentially be managed with the one-inflow C-T-BIMA; however, long-term outcome remains to be revealed.

Spontaneous avulsion of left internal mammary artery graft a complication of coronary artery bypass surgery: case report and review of the literature

BACKGROUND

Coronary artery bypass grafting (CABG) surgery is a common procedure for managing multi-vessel coronary artery disease to revascularize the myocardium. Among the various conduits used, the left internal mammary artery (LIMA) is preferred due to its better long-term patency rate. However, CABG procedures involving LIMA may result in rare but serious complications, such as avulsion of the LIMA post-CABG, which leads to disruption of blood flow to the myocardium and the development of fatal cardiac tamponade.

CASE PRESENTATION

We hereby present a unique case of spontaneous avulsion of a LIMA graft to the left anterior descending artery (LAD) away from the site of anastomosis, twenty-four hours following CABG surgery in a 67-year-old male patient. Emergency re-exploration and repair of the LIMA with interposition vein graft were performed and resulted in successful stabilization of the patient's critical condition. However, this was followed by a complicated recovery period involving atrial fibrillation, acute kidney injury, and wound infection.

CONCLUSION

Avulsion of LIMA graft following CABG is rare, yet a fatal complication that requires high clinical suspicion and prompt management. Avulsion has been reported a few times in literature following both minimal invasive and conventional CABG. Understanding the etiology, clinical presentation, and management of this complication is crucial to avoid catastrophic outcomes.

Surgical Myocardial Revascularization with a Composite T-graft from the Left Internal Mammary Artery-Comparison of the Great Saphenous Vein with the Radial Artery

BACKGROUND

 Composite T-grafts between left internal mammary artery (LIMA) and radial artery (RA) are a common concept in complete arterial myocardial revascularization. The aim of the present study was to investigate whether the use of the great saphenous vein (SV) instead of RA leads to comparably good results in terms of outcome in this context.

METHODS

 Patients who underwent myocardial revascularization with a T-graft using RA or a segment of SV to the right coronary artery or circumflex artery between the beginning of 2014 and the end of 2019 at the Department of Cardiovascular Surgery, University Hospital Schleswig-Holstein, Campus Kiel were included. To minimize surgical variation, only patients were observed by a single senior surgeon in the department. Exclusion criteria were previous cardiac surgery, preoperative extracorporeal circulatory support, off-pump surgery, additional aortocoronary bypasses, and cardiac combination procedures.

RESULTS

 A total of 115 patients were studied. In 55 patients, the T-graft was placed between the LIMA and SV, and in 60 patients, the T-graft was placed between the LIMA and RA. Patients in the SV group were older (70.6 ± 7.8 vs. 58.5 ± 10.0 years; p < 0.001), suffered more frequently from non-ST elevation myocardial infarction (12.7 vs. 1.7%; p = 0.027), arterial hypertension (83.6 vs. 61.7%; p = 0.009), and atrial fibrillation (18.2 vs. 1.7%; p = 0.003). They were less likely to be active smokers (16.4 vs. 38.3%; p = 0.009) and less likely to have a history of variceal surgery (0 vs. 15.0%; p = 0.003). Calcification of the ascending aorta was also found more frequently in the saphenous group (18.2 vs. 3.3%, p = 0.009). Operative times and number of distal anastomoses did not differ significantly between the two groups. Postoperative deliriums (16.7 vs. 5.0%; p = 0.043) were observed more frequently in venous patients. Wound healing disorders of the leg (11.1 vs. 0%; p = 0.011) did only occur in SV group and wound infections of the arm only in the RA group. Complete follow-up was achieved in 74.8% of cases. Median follow-up was 60.3 (39.6; 73.2) months. Serious adverse cardiac-cerebral events (19.0 vs. 22.7%; p = 0.675) and mortality (14.5 vs. 6.7%; p = 0.167) did not differ significantly between the groups at follow-up. Myocardial infarction (0 vs. 2.5%; p = 1.000) and stroke (0 vs. 7.5%; p = 0.245) were observed exclusively in RA group. Percutaneous coronary intervention was required in single patients of RA group (0 vs. 15.0%; p = 0.028). No patient from either group underwent repeat coronary artery bypass grafting (CABG). The patients of SV group had angiographically competent grafts and open anastomoses. Graft failure was noted in a single patient in RA group, in which case both grafts and native coronary vessels were stented. Kaplan-Meier analysis revealed no significant survival disadvantage for SV group compared with RA group.

CONCLUSION

 CABG with a composite T-graft between LIMA and a segment of SV may be comparable to bypass surgery with a composite T-graft between LIMA and RA. This might be true in terms of morbidity and mortality over an intermediate-term observation period. The results of our studies give rise to the hypothesis that the decision not to perform aortic bypass anastomosis may be more important than the choice of graft material.

Superior Outcomes of Dual-Arterial Coronary Artery Bypass Grafting Are Maintained in the Veterans Health Administration

INTRODUCTION

Controversy surrounds the long-term clinical benefit of coronary artery bypass grafting (CABG) using dual arterial grafts (DAGs) compared to single arterial grafts (SAGs). We investigated outcomes of DAG, using single internal thoracic artery and radial artery (DAG-RA) or bilateral internal thoracic artery grafts (DAG-BITA), compared to SAG, using the left internal thoracic artery and saphenous vein grafts, in the U.S. Veterans Health Administration (VA).

METHODS

We conducted a cross-sectional study of U.S. Veterans undergoing isolated on-pump CABG between 2005 and 2015 at 44 VA medical centers. The primary composite outcome was first occurrence of a major adverse cardiac and cerebrovascular event (MACCE), comprised of death from any cause, myocardial infarction, stroke, or repeat revascularization.

RESULTS

Among 25,969 Veterans undergoing isolated CABG, 1261 (4.9%) underwent DAG (66.8% DAG-RA and 33.2% DAG-BITA). Over a 5-y follow-up, DAG was associated with lower rates of all-cause death (adjusted hazard ratio [AHR] 0.70, 95% confidence interval [CI] 0.58-0.85), MACCE (AHR 0.80, 95% CI 0.71-0.91), and stroke (AHR 0.74, 95% CI 0.57-0.96) versus SAG. DAG-BITA was associated with lower rates of all-cause death (AHR 0.52, 95% CI 0.35-0.77) and MACCE (AHR 0.66, 95% CI 0.51-0.84) than SAG, while DAG-RA was associated with lower rates of all-cause death (AHR 0.79, 95% CI 0.64-0.99).

CONCLUSIONS

In the VA, DAG was associated with improved long-term MACCE outcomes compared to SAG. These results suggest that the practice of DAG in the VA benefits Veterans and should be promoted further.

Predominant Use of Bilateral Internal Mammary Arteries in Off-Pump Coronary Artery Bypass Surgery

Bilateral internal mammary artery (BIMA) in coronary artery bypass grafting (CABG) has been shown to provide long-term clinical benefits over single internal mammary artery (SIMA) grafting. Nevertheless, the perceived technical complexity of the procedure and concerns about potential early postoperative complications, particularly, sternal wound infections, have led to a utilization rate of BIMA grafting of less than 5% in the United States. We systematically compared early (30-day) postoperative outcomes between the BIMA and SIMA cohorts in patients with similar baseline characteristics. A retrospective single-center study was conducted on matched patients, using stabilized inverse probability treatment weighting to mitigate bias between the 2 study cohorts. From 546 patients who underwent off-pump CABG initially identified, we examined 328 BIMA and 213 SIMA grafts from the matched samples. Despite using 60.4% BIMA grafts, we observed similar rates of 30-day overall and cardiac mortality between the BIMA and SIMA groups. The rates of 30-day postoperative complications, including superficial and deep sternal wound infections, stroke, sepsis, acute kidney injury, and cardiac arrest, were similar between the 2 groups. The rates of 30-day overall and cardiac readmission were also similar. In addition, the median length of hospital stays, intensive care unit stay, and ventilation times were similar between the 2 groups. In conclusion, our data suggest that a BIMA utilization rate of 60.4% in off-pump CABG procedures is achievable without causing any significant increment in early postoperative complications, including deep sternal wound infection.

Efficacy of atrial fibrillation predictors including MVP ECG risk score compared between single or bilateral internal thoracic artery use

BACKGROUND

Atrial fibrillation (AF) is the most common complication after Coronary Artery Bypass Surgery (CABG). Despite advanced treatment methods, primary prevention is crucial. Many factors have been investigated as markers for AF, but further research is required. CABG is currently superior to Primary Coronary Intervention (PCI) in some cases due to Left Anterior Descending Artery (LAD)- Internal Thoracic Artery (ITA) anastomosis. However, graft choice for non-LAD vessels is still controversial. Our study compared the incidence of arrhythmia between patients with single ITA or bilateral ITA (BITA).

METHODS

The study included 84 isolated CABG patients. The patients were divided into two groups: single ITA and BITA. Patients who developed AF were recorded and compared.

RESULTS

73.8%(n = 62) of the patients were male and 26.2%(n = 22) were female. While single ITA was used in 48.8%(n = 41) of the patients, BITA was used in 51.2%(n = 43). AF was detected in 15.5%(n = 13) of the patients. AF was observed in 5(12.2%) patients in the single ITA group and 8(18.6%) in the BITA group. 76.9%(n = 10) of the patients with AF rhythm had Diabetes Mellitus (DM)(p = 0.011). Biphasic P wave, length of P wave duration, and total Morpholog-Voltage-P Wave ECG (MVP ECG) score height were statistically significantly different.

CONCLUSIONS

The development of AF was similar in both groups. The presence of DM, high blood glucose levels, and ECG findings can detect a predisposition to postoperative AF. MVP ECG risk score is effective as an AF marker and can be used in surgical patient groups.

Coronary angiography was used to assess the effect of diabetes on off-pump coronary artery bypass graft patency

This study aimed to examine the influence of diabetes on the left internal mammary artery (LIMA) and saphenous vein (SV) graft failure for 5-year follow-up. We enrolled 202 patients who underwent isolated off-pump coronary artery bypass grafting (CABG) surgery in 2014, angiographic follow-up occurred at 5 years after surgery. Angiographic outcomes in patients with or without diabetes were analyzed. Multivariate logistic regression analysis was used to identify independent predictors of graft dysfunction. A total of 66 (32.7%) patients had diabetes. Five-year rates of LIMA and SV graft failure were similar in patients with and without diabetes. In addition, in diabetics, the proportion of complete graft failure was significantly lower in the LIMA grafts (12/66, 18.2%) than in the SV grafts (57/133, 42.9%) (P = .001). In nondiabetic, the proportion of complete graft failure was also significantly lower in the LIMA grafts (28/136, 20.6%) than in the SV grafts (105/275, 38.2%) (P < .001). Multivariate logistic regression analysis showed that mean graft flow (MGF) was an independent predictor factor for LIMA (odds ratio = 1.186, 95% CI = 1.114-1.263, P < .001) and SV (odds ratio = 1.056, 95% CI = 1.035-1.077, P < .001) graft failure. Diabetes did not influence the patency of LIMA or SV grafts over a 5-year follow-up. LIMA grafts should be maximized in patients undergoing off-pump CABG surgery. Diabetes does not affect the patency of grafts CABG. Using angiography, our study proved that diabetes does not affect the patency of grafted vessels after CABG for 5 years.

Rationale and design of a single-center randomized trial to compare the graft patency between the radial artery and the no-touch saphenous vein in coronary artery bypass grafting surgery (GRAFT-CAB Study)

BACKGROUND

Previous studies suggested only the radial artery and the No-touch (NT) technique were effective in reducing graft occlusion after coronary artery bypass grafting (CABG) surgery. However, there is no randomized trial comparing these 2 graft conduits. The optimum second conduit for CABG remains undetermined.

MATERIALS AND METHODS

This study is a prospective, single-center randomized clinical trial, aiming to compare the graft patency between the radial artery and the NT vein graft. All patients undergoing isolated CABG with left internal mammary artery (LIMA) plus at least 2 additional grafts will be considered eligible. About 774 cases (516 in the radial artery group and 258 in the NT vein group) will be enrolled in over 1 to 2 years. Participants will be randomized and allocated to two bypass strategies: the LIMA plus 1 radial artery and 1 conventional vein graft, or the LIMA plus 2 NT vein grafts. The primary outcome is graft occlusion at 1 year after CABG evaluated by CT angiography. The secondary outcomes include graft occlusion at 3 and 5 years and major adverse cardiac or cerebrovascular events at 1, 3, and 5 years follow-ups.

DISCUSSION

This study will define whether or not the NT vein has a lower graft occlusion rate than the radial artery in short and mid-term follow-ups, and provide new evidence for the second conduit choice in CABG surgery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06014047. Registered on October 15th, 2023.

Clinical and financial outcomes associated with the utilization of right internal mammary artery versus radial artery in multivessel coronary artery bypass grafting

BACKGROUND

Multi-arterial coronary bypass grafting with the left internal mammary artery as a conduit has been shown to offer superior long-term survival compared to single-arterial coronary bypass grafting. Nevertheless, the selection of a secondary conduit between the right internal mammary artery and the radial artery remains controversial. Using a national cohort, we examined the relationships between the right internal mammary artery and the radial artery with acute clinical and financial outcomes.

METHODS

Adults undergoing on-pump multivessel coronary bypass grafting with left internal mammary artery as the first arterial conduit were identified in the 2016 to 2020 Nationwide Readmissions Database. Patients receiving either the right internal mammary artery or the radial artery, but not both, were included in the analysis. Multivariable regression models were fitted to examine the association between the conduits and in-hospital mortality, as well as additional secondary outcomes.

RESULTS

Of an estimated 49,798 patients undergoing multi-arterial coronary bypass grafting, 29,729 (59.7%) comprised the radial artery cohort. During the study period, the proportion of multi-arterial coronary bypass grafting utilizing the radial artery increased from 51.3% to 65.2% (nptrend <0.001). Following adjustment, the radial artery was associated with reduced odds of in-hospital mortality (adjusted odds ratio 0.44), prolonged mechanical ventilation (adjusted odds ratio 0.78), infectious complications (adjusted odds ratio 0.69), and 30-day nonelective readmission (adjusted odds ratio 0.77, all P < .05).

CONCLUSION

Despite no definite endorsement from surgical societies, the radial artery is increasingly utilized as a secondary conduit in multi-arterial coronary bypass grafting. Compared to the right internal mammary artery, the radial artery was associated with lower odds of in-hospital mortality, complications, and reduced healthcare expenditures. These results suggest that whenever feasible, the radial artery should be the favored conduit over the right internal mammary artery. Nevertheless, future studies examining long-term outcomes associated with these vessels remain necessary.

Outcomes of internal mammary artery perforator flap in head and neck reconstruction: A systematic review

This study aims to evaluate the functional and prognostic outcomes associated with the internal mammary artery perforator (IMAP) flap in various head and neck defect repairs, given the current lack of clarity on its effectiveness. We performed a systematic review of various databases: PubMed, Embase, Scopus, Web of Science, and ScienceDirect using keywords such as "Internal mammary artery perforator flap" and "IMAP." Screening and data extractions were performed by two individual reviewers. Articles were considered eligible if they included sufficient information on IMAP flap features, their applications in the head and neck, and outcomes. From 264 articles analyzed, 24 studies were included for qualitative analysis. Out of which, 125 patients who received internal mammary artery perforator flaps were included. Most of the patients, 103 (88%), received pedicled IMAP flaps, and 22 (12%) received IMAP free flaps. The second internal mammary artery (IMA) was favored as the single perforator (81.5%), with the combination of the first and second IMA being the primary choice for dual perforators (92.5%). IMAP flaps were predominantly single perforator flaps (65%), with 35% being dual perforator flaps. Among various applications, IMAP flaps are commonly employed in the reconstruction of neck defects (25.5%), pharyngocutaneous fistula repair (20.8%), and burn scar contracture restoration (8%). Only seven (5.6%) patients had flap complications, including venous congestion (1.6%), partial necrosis (1.6%), complete necrosis (1.6%), and incision dehiscence (0.8%). Donor sites were predominantly closed by the primary closure (92%). 3.2% of donor sites had minor complications. The average follow-up was 12.6 (IQR: 6-18) months. This systematic review highlights the effectiveness and safety of IMAP flaps in head and neck reconstruction, with positive outcomes and minimal complications.

The internal mammary artery perforator flap in pharyngoesophageal, cervical tracheal, and cutaneous neck reconstruction

The internal mammary artery perforator (IMAP) flap is an evolution of the deltopectoral flap that is harvested based upon a single perforator from the internal mammary artery. Its favorable characteristics include pliability as a fasciocutaneous flap, ease of harvest, and minimal donor site morbidity. In this paper, we report our harvest technique and the versatility of the IMAP flap for pharyngoesophageal, cervical tracheal, and cutaneous neck defects. We seek to highlight the IMAP as a useful regional reconstructive option in both the primary and salvage reconstructive setting. As such, this flap is an important option in the head and neck reconstructive surgeon's armamentarium.

Skeletonized Versus Pedicled Harvesting of the Internal Thoracic Artery and Long-Term Clinical Outcomes in Coronary Artery Bypass Surgery

BACKGROUND

The internal thoracic artery (ITA) is the most important conduit for coronary artery bypass grafting. Recent evidence suggests that skeletonized ITA harvesting yields long-term outcomes inferior to those of pedicled harvesting. The aim was to investigate the impact of the ITA harvesting method on 10-year mortality and major adverse cardiovascular events.

METHODS AND RESULTS

In this observational cohort study, we identified all patients from the SWEDEHEART (Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) register who underwent isolated coronary artery bypass grafting using at least 1 ITA at Karolinska University Hospital from 2012 to 2021. The main outcome was all-cause mortality, and the secondary outcomes were a combination of myocardial infarction, repeat revascularization, heart failure, and stroke. Outcomes were ascertained using national health data registers and compared between the skeletonized and pedicled groups using weighted flexible parametric survival models. Among 3267 patients, 1657 (51%) underwent pedicled ITA harvesting and 1610 (49%) underwent skeletonized ITA harvesting. The patients' mean age was 66 years, and 15% were women. The weighted all-cause mortality incidence rate in the pedicled versus skeletonized ITA group was 2.6% (95CI, 2.2%-3.0%) versus 2.6% (95% CI, 2.2%-3.1%), respectively (hazard ratio (HR), 1.01 [95% CI, 0.81-1.27]). The weighted major adverse cardiovascular events incidence rate was 7.8% (95% CI, 7.1%-8.6%) versus 7.5% (95% CI, 6.7%-8.4%), respectively (HR, 0.94 [95% CI, 0.82-1.08]).

CONCLUSIONS

We found no significant differences in all-cause mortality or major adverse cardiovascular events rates between the 2 ITA harvesting methods.

Importance of the Internal Thoracic Artery as the Source of Collateral Circulation in CABG Patients with Leriche Syndrome

In coronary artery bypass grafting (CABG) the use of the internal thoracic artery (ITA), is a Class I indication for the left anterior descending (LAD) artery. Atherosclerosis is a systemic disease, and peripheral arterial disease (PAD) is an important complicator of CABG, present in about one-third of the patients with coronary disease. In Leriche Syndrome, ITA can be the source of collateral circulation for arteries below the level of occlusion. Its inadvertent use can lead to serious ischemic complications in the dependent territories.

Internal mammary artery perforator flap in the management of tracheoesophageal fistulae

BACKGROUND

A pathological communication between the trachea and oesophagus - a tracheoesophageal fistula - may be congenital or acquired, benign or malignant, necessitating a multidisciplinary approach. Conservative attempts at closure of this abnormal connection are ineffective; the interposition of healthy vascular tissue offers the least chance of recurrence.

METHODS

Outcomes of an islanded fasciocutaneous internal mammary artery perforator flap applied for tracheoesophageal fistula management were assessed in four radiated patients with laryngeal carcinoma using retrospective records.

RESULTS

Four male patients, with an average age of 60.75 years, underwent tracheoesophageal fistula closure between September 2017 and February 2021. A left-sided second internal mammary artery perforator flap was used in all cases, with an average dimension of 10.5 × 4.5 cm. There were no complications of tracheoesophageal leak, flap issues or donor site morbidity on follow up.

CONCLUSION

Recent advances in angiosomal territory mapping and microvascular dissection techniques, combined with an understanding of tracheoesophageal fistula pathology, have changed management perspectives in these difficult-to-treat patients.

From a Position of Known Angiographic Perfect Patency: What Happens Next?

BACKGROUND AND AIM

The biological behaviour of coronary graft conduits over time may be considered by serial angiography.

METHODS

A single institution retrospective cohort received mostly clinically indicated angiography between 1997 and 2020, following coronary bypass surgery. Only perfectly patent grafts (absence of any lumen irregularity) for each conduit type at the first postoperative angiogram were selected for a later comparison. The latest angiograms were at least 5 years postoperatively, and at least 1 year after first postoperative angiogram. Analysis was done according to each graft (anastomosis). Comparisons used generalised estimating equations, adjusted for binary logistic regression.

RESULTS

Of 143 patients, there were 410 of 468 (87.6%) perfectly patent grafts at the first angiogram, analysed at 6.8±4.0 years postoperative, of which 157 were internal mammary arteries, 228 were radial arteries, and 25 were saphenous veins. At the latest angiogram (12.2±3.8 years postoperative), comparison with the first angiogram for each individual graft found preserved perfect patency for internal mammary arteries, 156 of 157 (99.4%), and for radial arteries, 227 of 228 (99.6%) but saphenous veins deteriorated considerably, 13 of 25 (52.0%). The two arterial grafts (internal mammary and radial) were superior to vein grafts (odds ratio 163; 95% confidence interval [CI] 22-1,211; p<0.001), but not different from each other (odds ratio 0.95; 95% CI 0.78-1.16; p=0.584).

CONCLUSIONS

From a position of known angiographic perfect patency post-CABG, internal mammary artery and radial artery grafts retained their perfect patency in the longer term, but saphenous vein grafts did not.

Post-pneumonectomy coronary artery bypass graft surgery

Postpneumonectomy changes, including ipsilateral diaphragmatic elevation and rib crowding, mediastinal shifting of the heart and reduction of respiratory functional reserve by 45%-55%, make cardiac surgery challenging in terms of access to the heart and great vessels. There is a paucity of literature on coronary artery bypass graft (CABG) surgery in patients with a history of pneumonectomy. We report a case of a male in his 70s with a history of left pneumonectomy who underwent a successful on-pump CABG surgery using the left internal mammary artery graft and great saphenous vein graft. The patient was extubated postoperatively and discharged in a stable condition. With no consensus available for optimal preoperative, intraoperative and postoperative management for these high-risk patients, our case report adds to the rare literature regarding successful on-pump CABG after pneumonectomy.

Performance of left internal thoracic artery-left anterior descending artery anastomosis by residents versus attendings and coronary artery bypass grafting outcomes

OBJECTIVES

Performance of a technically sound left internal thoracic artery to left anterior descending artery (LITA-LAD) anastomosis during coronary artery bypass grafting (CABG) is critically important. We used prospectively collected data from the multicentre, randomized REGROUP (Randomized Endograft Vein Perspective) trial to investigate CABG outcomes based on whether a resident or an attending surgeon performed the LITA-LAD anastomosis.

METHODS

This was a post hoc subanalysis of the REGROUP trial, which randomized veterans undergoing isolated on-pump CABG to endoscopic versus open vein harvest from 2014 through 2017. The primary end point was major cardiac adverse events, defined as the composite of all-cause deaths, nonfatal myocardial infarctions or repeat revascularizations.

RESULTS

Among 1,084 patients, 344 (31.8%) LITA-LAD anastomoses were performed by residents and 740 (68.2%), by attending surgeons. Residents (compared to attendings) operated on fewer patients with high tercile SYNTAX scores (22.1% vs 37.4%, P < 0.001), performed fewer multiarterial CABGs (5.2% vs 14.6%, P < 0.001) and performed more anastomoses to distal targets with diameters > 2.0 mm (19.0% vs 10.9%, P < 0.001) and non-calcified landing zones (25.1% vs 21.6%, P < 0.001). During a median observation time of 4.7 years (interquartile range 3.84-5.45), major cardiac adverse events occurred in 77 patients (22.4%) in the group treated by residents and 169 patients (22.8%) in the group treated by attendings (unadjusted HR 1.00; 95% confidence interval, 0.76-1.33; P = 0.99). Outcomes persisted on adjusted analyses.

CONCLUSIONS

Based on this REGROUP trial subanalysis, under careful supervision and with appropriate patient selection, LITA-LAD anastomoses performed by the residents yielded clinical outcomes similar to those of the attendings.

Strategies for arterial graft optimization at the single-cell level

Common arterial grafts used in coronary artery bypass grafting include internal thoracic artery (ITA), radial artery (RA) and right gastroepiploic artery (RGA) grafts; of these, the ITA has the best clinical outcome. Here, by analyzing the single-cell transcriptome of different arterial grafts, we suggest optimization strategies for the RA and RGA based on the ITA as a reference. Compared with the ITA, the RA had more lipid-handling-related CD36+ endothelial cells. Vascular smooth muscle cells from the RGA were more susceptible to spasm, followed by those from the RA; comparison with the ITA suggested that potassium channel openers may counteract vasospasm. Fibroblasts from the RA and RGA highly expressed GDF10 and CREB5, respectively; both GDF10 and CREB5 are associated with extracellular matrix deposition. Cell-cell communication analysis revealed high levels of macrophage migration inhibitory factor signaling in the RA. Administration of macrophage migration inhibitory factor inhibitor to mice with partial carotid artery ligation blocked neointimal hyperplasia induced by disturbed flow. Modulation of identified targets may have protective effects on arterial grafts.

Transient time flow measurement in arterial grafts

Coronary artery bypass grafting (CABG) is one of the foundations of treatment for coronary artery disease. While it has improved substantially since its inception more than 50 years ago, including a rising use of multiple arterial grafting, intraoperative quality assessment is yet to be disseminated as an integral part of the procedure. Herein we review the fundamentals of intraoperative quality assessment in CABG using transient time flow measurement (TTFM) with a focus on its use in arterial grafting.

Radial artery vs right internal mammary artery as a second conduit during coronary artery bypass grafting

OBJECTIVE

To compare the clinical outcomes of radial artery (RA) grafts during CABG to those of right internal mammary artery (RIMA) grafts.

METHODS

This was a retrospective, single-institution cohort study of isolated CABG with multiple grafts between 2010-2022. To balance graft cohorts, propensity score matching (PSM) was performed using a 1:1 match ratio. Long-term postoperative survival was compared among RA and RIMA groups. Similarly, major adverse cardiac and cerebrovascular events (MACCE) were compared among both cohorts, with MACCE comprising death, myocardial infarction (MI), coronary revascularization, and stroke. Kaplan-Meier estimation was performed for mortality, while cumulative incidence estimation was utilized for MACCE.

RESULTS

A total of 8,774 patients underwent CABG. Of those, 1,674 (19.1%) patients who underwent multiarterial CABG were included in this analysis. 326 (19.5%) patients received RA grafts and 1,348 (80.5%) received RIMA grafts. PSM yielded a cohort of 323 RA patients and 323 RIMA patients. After matching, groups were well-balanced across all baseline variables. No significant differences were observed in immediate postoperative complications or long-term survival, with 5-year survival estimates of 89.5% for the RA group vs 90.1% for the RIMA group. There was a nonsignificant trend toward a higher incidence of MACCE at 5 years in the RA group compared to the RIMA group (31.3% in the RA group vs 24.1% in the RIMA group), especially after 1-year follow-up (21.6% in the RA group vs 15.1% in the RIMA group). Specifically, for RA patients, there were higher rates of repeat revascularization in the 5-year postoperative period (14.7% in the RA group vs 5.3% in the RIMA group), particularly in the territory revascularized by the RA during the index operation (45.7% in the RA group vs 10.3% in the RIMA group).

CONCLUSION

Overall, RA and RIMA secondary conduits for CABG were associated with comparable immediate postoperative complications, 5-year MACCE, and 5-year survival after PSM. RA grafting was associated with significantly higher rates of repeat coronary revascularization at 5 years, specifically in the territory revascularized by the RA during the index operation.

Impact of coronary-subclavian steal after surgical myocardial revascularization with internal thoracic artery in chronic hemodialysis patients: A meta-analysis

Patients in hemodialysis with an arm arteriovenous fistula undergoing coronary artery bypass grafting (CABG) with an internal thoracic artery have been reported to suffer from coronary-subclavian steal (CSS) during dialysis session. However, its occurrence is still debated. A systematic literature review was performed to identify all studies investigating the occurrence of a CSS event in this subset of patients. The primary endpoint was the analysis of CSS and the following early and late survival outcomes. Independent determinants of CSS and the impact of the distance between the arteriovenous fistula (upper arm vs forearm) and the ipsilateral internal thoracic artery graft on CSS events and mortality were studied. Early and late survival outcomes were analyzed by comparing ipsilateral versus contralateral arteriovenous fistula. Of the 1,383 retrieved articles, 10 were included (n = 643 patients). The pooled event rate of CSS was 6.46% [95%CI=2.10-18.15], while of symptomatic CSS incidence was 3.99% [95%CI=0.95-15.25]. No survival differences were noted when comparing ipsilateral to contralateral arteriovenous fistula-internal thoracic artery combinations. On meta-regression, the upper arm was associated with more CSS events, while the forearm to lower late mortality rates. Independently from arteriovenous fistula-internal thoracic artery combination, CSS was not associated to higher mortality rates. Particular attention is warranted when selecting the type of conduits for CABG in patients with an arteriovenous fistula or if highly expected to need one in the near future after surgery. A contralateral arteriovenous fistula-internal thoracic artery combination is preferable. If this is not possible, a forearm arteriovenous fistula position should be preferred.

Long-term observational angiographic patency and perfect patency of radial artery compared with saphenous vein or internal mammary artery in coronary bypass surgery

OBJECTIVES

It is uncertain if the long-term biological behavior of the radial artery as a conduit for coronary bypass surgery has a similar resistance to the development of atherosclerosis as for the internal mammary artery. We aimed to examine long-term angiographic patency and disease-free patency (perfect patency) for internal mammary artery, radial artery, and saphenous vein grafts.

METHODS

A retrospective, single-center, individual patient cohort study of angiographic observations from patients' latest postoperative angiogram from 1997 to 2020 was performed. Analysis was per anastomosis and assessed for patency and perfect patency. A generalized linear mixed model premised upon logistic regression was used to minimize confounding bias.

RESULTS

A total of 983 patients with 3064 grafts were included, with a median follow-up of 8.6 (interquartile range, 4.4-12.6) years after the operation. Multivariable analysis revealed differences for radial (patency, 86.9%; perfect patency, 86.4%) and internal mammary artery (patency, 93.9%; perfect patency, 93.5%) versus saphenous vein graft (patency, 72.8%; perfect patency, 46.2%). There were no differences between the 2 arterial conduits for patency (odds ratio, 1.40; 95% CI, 0.85-2.33; P = .189) and perfect patency (odds ratio, 1.14; 95% CI, 0.71-1.84; P = .578). If a conduit was patent, then 99.4% of radial artery, 99.6% of internal mammary artery, and 63.5% of saphenous vein graft were reported as perfectly patent.

CONCLUSIONS

Radial artery and internal mammary artery had similar patency and perfect patency while both were superior to saphenous vein graft.

Comparative Analysis of Coronary Artery Bypass Grafting Outcomes in Women Using Different Conduits in the National UK Data Set

BACKGROUND

There is limited report of outcomes in women undergoing isolated coronary artery bypass grafting (CABG) with left internal thoracic artery and different second conduits (saphenous vein graft [SVG], radial artery [RA], and right internal thoracic artery [RITA]).

METHODS

The National Adult Cardiac Surgery Audit database was queried for women undergoing isolated CABG with left internal thoracic artery graft in the United Kingdom from 1996 to 2019. Propensity score-based pairwise comparisons were performed between graft types. The primary outcome was in-hospital mortality.

RESULTS

The study included 58,063 women (SVG, n = 48,881 [84.2%]; RA, n = 6136 [10.6%]; RITA, n = 2445 [4.2%]). SVG use was stable over the years; RA and RITA use decreased. In-hospital mortality was similar between the RA and RITA grafts (2.3% vs 2.8%; odds ratio [OR], 0.80; 95% CI, 0.53-1.22; P = .39) and between the RA and SVG (2.3% vs 2.0%; OR, 1.20; 95% CI, 0.93-1.55; P = .17) but higher in the RITA group compared with the SVG (2.7% vs 1.4%; OR, 2.04; 95% CI, 1.27-3.36; P = .004). Women receiving the RITA graft were more likely to have sternal wound infection (SWI) compared with the RA (0.6% vs 0.06%; P = .004) and the SVG (0.6% vs 0.2%; P = .032). SWI was consistently associated with higher risk of in-hospital mortality.

CONCLUSIONS

Conduit selection may affect operative outcomes in women undergoing CABG. The RA shows similar mortality and risk of deep SWI as the SVG.

Saphenous vein to the right coronary system from the right thoracic artery or the aorta. Long-term propensity-matched results of 2 groups

OBJECTIVES

Since 2000, we anastomosed the saphenous vein graft to the right coronary artery system using the stump of the right internal thoracic artery as inflow. The long-term results of patients where the right coronary artery was grafted with the right internal thoracic artery or the ascending aorta as saphenous vein inflow has not been reported.

METHODS

From 2000 to 2018, 699 consecutive patients had right internal thoracic artery elongated with saphenous vein (I-graft group, n = 358, 51.2%) or saphenous vein from the aorta (Ao-graft group, n = 341, 48.8%) on right coronary artery system. Inclusion criteria were age ≤75 years, bilateral internal thoracic arteries as a Y graft on the left system (three-vessel disease, n = 603, 86.3%) or as a left internal thoracic artery on left anterior descending and right internal thoracic artery elongated with saphenous vein on the right coronary artery system (two-vessel disease, n = 96, 13.7%), only 1 saphenous vein per patient. Propensity-matching identified 272 patients per group. One-hundred and twenty-two patients underwent coronary computed tomographic angiography to asses grafts patency after a median follow-up of 88 (65-93) months.

RESULTS

In the paired samples, there was no difference in the early outcome. Ten-year survival and freedom from death, non-fatal acute myocardial infarction and repeat revascularization were higher in I-graft group: 90.6 [standard error (SE): 2.0] vs 78.2 (SE: 5.3), P = 0.0266, and 85.2 (SE: 2.4) vs 69.9 (SE: 5.3), P = 0.0179. Saphenous vein graft, at a long-time follow-up, showed a higher patency rate (81.6% (SE: 7.0) vs 50.7% (SE: 7.9), P < 0.0001) and a smaller internal lumen diameter (2.7, standard deviation: 0.4 vs 3.4, standard deviation: 0.6 mm, P < 0.0001) when right internal thoracic artery was the inflow.

CONCLUSIONS

Grafting the right coronary artery with saphenous vein may entail higher patency rate and better outcome when the inflow is the right internal thoracic artery than when is the ascending aorta. Prospective randomized data are needed to test this hypothesis.

Effect of right internal mammary artery versus radial artery as a second graft vessel in coronary artery bypass grafting on postoperative wound infection in patients: A meta-analysis

Few studies have shown that radial artery (RA), which is used as a secondary arterial graft, offers superior results compared with right internal thoracic artery (RIMA) in coronary artery bypass grafting (CABG). In a meta-analysis of observational studies starting in 2023, we looked at the effect of re-operation on postoperative infection and haemorrhage in CABG with RA vs. RIMA. The electronic database up to October 2023 was examined in the course of the research. Analysis was carried out on the clinical trials of postoperative wound infections and haemorrhage re-surgery. Among 912 trials associated with CABG, we selected 8 trials to be included in the final data analysis. The main results were secondary wound infection and re-operation after surgery. The odds ratios (OR) and confidence intervals (CIs) were computed on the basis of a randomized or fixed-effect model of wound infection and re-operation. Seven trials showed a significant reduction in the risk of wound infection in RA treated as a secondary artery transplant compared with RIMA (OR, 1.60; 95% CI, 1.03, 2.47 p = 0.04); Four trials showed that RIMA was not significantly different from RA in the rate of re-operation for postoperative bleeding (OR, 1.31; 95% CI, 0.60, 2.88 p = 0.50). In CABG, RA is used as a secondary arterial conduit graft to lower the risk of wound infection in CABG patients.