Trends in isolated coronary artery bypass grafting: An analysis of the Society of Thoracic Surgeons adult cardiac surgery database

No improvements in long-term outcome after coronary artery bypass grafting with arterial grafts as a second conduit: a Swedish nationwide registry study

OBJECTIVES

Coronary artery bypass grafting using saphenous vein grafts (SVGs) in addition to the left internal mammary artery (IMA) graft is vitiated by poor long-term patency of the vein grafts. Hypothetically, the increased use of arterial grafts could confer even better outcomes. Our goal was to evaluate results after coronary artery bypass grafting in Sweden, where arterial grafts were used as a second conduit.

METHODS

Within the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART) registry, we identified patients who had coronary artery bypass grafting from 2001 to 2015 using the IMA and the SVG, the radial artery (RA) or the additional IMA [bilateral IMA (BIMA)] as a second conduit. Deaths, postoperative incidence of coronary angiography and need for reintervention were recorded, and multivariable adjusted hazard ratios were calculated for different types of grafts.

RESULTS

The study population comprised 46 343 cases of IMA + SVG, 1036 cases of IMA + RA and 862 cases of BIMA. The mean follow-up time (SD) was 9.3 (4.2) years for IMA + SVG, 10.7 (4.1) years for IMA + RA grafts and 5.5 (5.0) years for the BIMA graft. The adjusted hazard ratio for death was (95% confidence interval) 1.01 (0.89-1.14) for IMA + RA and 0.87 (0.72-1.06) for BIMA grafts compared with IMA + SVG. The adjusted hazard ratio for the first angiographic examination was (95% confidence interval) 0.96 (0.84-1.10) for IMA + RA and 1.13 (0.95-1.35) for BIMA grafts. The adjusted hazard ratio for the need for reintervention was (95% confidence interval) 0.91 (0.75-1.09) for IMA + RA and 1.26 (1.00-1.58) for BIMA grafts.

CONCLUSIONS

Patients who had arterial grafts as second conduits did not demonstrate a better outcome in any of the studied end-points. Radial artery grafts seem to be preferable to BIMA grafts as an alternative to an SVG.

The no-touch saphenous vein is an excellent alternative conduit to the radial artery 8 years after coronary artery bypass grafting: A randomized trial

BACKGROUND

In 2004, a prospective randomized trial demonstrated that after 3 years, saphenous veins (SVs) harvested with a no touch (NT) technique had a greater patency than radial grafts for coronary bypass surgery. Here we report the 8-year follow-up data of this trial.

METHODS

The trial included 108 patients undergoing coronary artery bypass grafting (CABG). Each patient was assigned to receive 1 NT SV and 1 radial artery (RA) graft to either the left or right coronary territory to complement the left internal thoracic artery (LITA). Sequential grafting was common, so overall graft patency as well as the patency of each anastomosis were assessed.

RESULTS

Angiography was performed in 84 patients (78%) at mean of 97 months postoperatively. Graft patency were high and similar for both NT and RA: 86% for NT versus 79% for RA (P = .22). The patency of coronary anastomoses was significantly higher with the NT SV grafts (91% vs 81%; P = .046). The NT grafts also had excellent patency in coronary arteries with <90% stenosis (93% patency) and in coronary arteries of small diameter (87% patency) or with mild calcification (88% patency). Patency for the LITA was 92%.

CONCLUSIONS

NT SV grafts have excellent patency similar to that of RA grafts after 8 years. In addition, NT SV grafts can be used in situations that are not ideal for RA grafts.

Synchronous versus Staged Carotid Endarterectomy and Coronary Artery Bypass Graft for Patients with Concomitant Severe Coronary and Carotid Artery Stenosis: A Systematic Review and Meta-analysis

BACKGROUND

Due to the systemic nature of atherosclerosis, arteries at different sites are commonly simultaneously affected. As a result, severe coronary artery disease (CAD) requiring coronary artery bypass grafting (CABG) frequently coexists with significant carotid stenosis that warrants revascularization. To compare simultaneous carotid endarterectomy (CEA) and CABG versus staged CEA and CABG for patients with concomitant CAD and carotid artery stenosis in terms of perioperative outcomes.

METHODS

This study was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. A meta-analysis was conducted with the use of a random effects model. The I² statistic was used to assess for heterogeneity.

RESULTS

Eleven studies comprising 44,895 patients were included in this meta-analysis (21,710 in the synchronous group and 23,185 patients in the staged group). The synchronous CEA and CABG group had a statistically significant lower risk for myocardial infarction (MI) (odds ratio [OR] 0.15, 95% CI 0.04-0.61, I² = 0%) and higher risk for stroke (OR 1.51, 95% CI 1.34-1.71, I² = 0%) and death (OR 1.33, 95% CI 1.01-1.75, I² = 47.8%). Transient ischemic attacks (TIAs) (OR 1.27, 95% CI 1.00-1.61, I² = 0.0%), postoperative bleeding (OR 0.82, 95% CI 0.22-3.05, I² = 0.0%), and pulmonary complications (OR 1.52, 95% CI 0.24-9.60, I² = 67.5%) were similar between the 2 groups.

CONCLUSIONS

Patients in the simultaneous CEA and CABG group had a significantly higher risk of 30-day mortality and stroke and lower risk for MI as compared to staged CEA and CABG group. The rates of TIA, postoperative bleeding, and pulmonary complications were similar between the 2 groups. Future randomized trials or prospective cohorts are needed to validate our results.

Differences in Expression of Genes Involved in Bone Development and Morphogenesis in the Walls of Internal Thoracic Artery and Saphenous Vein Conduits May Provide Markers Useful for Evaluation Graft Patency

Coronary artery bypass grafting (CABG) is one of the most efficient procedures for patients with advanced coronary artery disease. From all the blood vessels with the potential to be used in this procedure, the internal thoracic artery (ITA) and the saphenous vein (SV) are the most commonly applied as aortocoronary conduits. Nevertheless, in order to evaluate the graft patency and efficiency effectively, basic knowledge should be constantly expanding at the molecular level as well, as the understanding of predictive factors is still limited. In this study, we have employed the expressive microarray approach, validated with Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR), to analyze the transcriptome of both venous and arterial grafts. Searching for potential molecular factors, we analyzed differentially expressed gene ontologies involved in bone development and morphogenesis, for the possibility of discovery of new markers for the evaluation of ITA and SV segment quality. Among three ontological groups of interest—“endochondral bone morphogenesis”, “ossification”, and “skeletal system development”—we found six genes common to all of them. BMP6, SHOX2, COL13A1, CSGALNACT1, RUNX2, and STC1 showed differential expression patterns in both analyzed vessels. STC1 and COL13A1 were upregulated in ITA samples, whereas others were upregulated in SV. With regard to the Runx2 protein function in osteogenic phenotype regulation, the RUNX2 gene seems to be of paramount importance in assessing the potential of ITA, SV, and other vessels used in the CABG procedure. Overall, the presented study provided valuable insight into the molecular background of conduit characterization, and thus indicated genes that may be the target of subsequent studies, also at the protein level. Moreover, it has been suggested that RUNX2 may be recognized as a molecular marker of osteogenic changes in human blood vessels.

Diagnosis and Management of Ischemic Mitral Regurgitation: Evidence-Based Clinical Decision Making at the Point of Care

Anatomical, functional, and pathophysiologic mechanisms of ischemic mitral regurgitation (IMR) are markedly different from the primary mitral regurgitation. The older and ubiquitous cutoff of EROA (effective regurgitant orifice area) and Rvol (regurgitant volume) for IMR has been reinstated in the new guideline after a brief hiatus. There had always been a lack of good-quality evidence for its introduction for guiding IMR severity in the previous guideline, and we still do not have quality evidences that could justify its reintroduction. Unlike primary MR, IMR is usually associated with reduced ejection fraction. Therefore, it appears unrealistic to keep the similar cutoff for primary MR and IMR. The cutoff of severity can be modified according to projected values of Rvol normalized to ejection fraction and EROA normalized to Rvol. In addition, the treatment outcome in these patients is determined by factors (left ventricular dyssynchrony, annular dilatation, tenting area, tenting height, tenting volume, and myocardial viability) other than the simple grading. In this review article, a series of graph have been constructed from the numerical data derived from the literatures on IMR to depict the relationship between EROA, Rvol, left ventricular end diastolic volume, and ejection fraction in order to obtain a reasonable projection formula for EROA and Rvol. Furthermore, a management algorithm has been proposed for patients with IMR undergoing coronary artery bypass grafting based on echocardiographic predictors that influence the postoperative outcome.

Multiarterial coronary artery bypass grafting: is the radial artery fulfilling the unkept promise of the right internal thoracic artery?

PURPOSE OF REVIEW

The debate on the second best conduit for CABG is still intense. In this review, we discuss the role of the radial artery and the right internal thoracic artery (RITA) compared with saphenous vein grafts (SVG).

RECENT FINDINGS

The recent RADIAL STUDY has been the first evidence based on randomized trials of a clinical benefit using a second arterial graft in CABG.On the other hand, the definitive 10-year results of the ART trial failed to show a clinical advantage associated with the use of bilateral internal thoracic artery (BITA). A thorough and contextualized analysis of this and other studies, however, may offer a different perspective.

SUMMARY

Arterial conduits in CABG have shown better patency rates than SVG. Whether this leads to better clinical outcomes is still debated. In this setting, the radial artery and the RITA seem to offer a similar advantage, although with different indications and contraindications.

Implications of coronary artery bypass grafting and percutaneous coronary intervention on disease progression and the resulting changes to the physiology and pathology of the native coronary arteries

Myocardial revascularization can be achieved through 2 different methods: coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). Clinical trials comparing PCI and CABG generally use the composite end points of death, stroke, myocardial infarction and target vessel revascularization to determine superiority. Other effects of these interventions, including the preservation of normal coronary physiology, the response of the coronary tree to stressors and the response of the vessel wall to the revascularization intervention, are not routinely considered, but these may have significant implications for patients in the medium and long term. For PCI, relatively small differences in clinical outcomes have been reported between bare metal and drug-eluting stents, and the latter seems to have inconsistent and somewhat unpredictable effects on the vascular biology of the coronary arteries. In coronary bypass, the use of arterial conduits is associated with superior clinical outcomes, better long-term patency and the preservation of essentially normal coronary function after intervention. This review assembles the clinical, physiological, angiographic and pathological literature currently available and attempts to provide a more complete picture of the effects of CABG and PCI on coronary arteries.

Long-term Outcomes of Multiple Arterial Coronary Artery Bypass Grafting: A Population-Based Study of Patients in British Columbia, Canada

Importance

Although the long-term survival advantage of multiple arterial grafting (MAG) vs the standard use of left internal thoracic artery (LITA) supplemented by saphenous vein grafts (LITA+SVG) has been demonstrated in several observational studies, to our knowledge its safety and other long-term clinical benefits in a large, population-based cohort are unknown.

Objective

To compare the safety and long-term outcomes of MAG vs LITA+SVG among overall and selected subgroups of patients.

Design, Setting, and Participants

In this population-based observational study, we included 20 076 adult patients with triple-vessel or left-main disease who underwent primary isolated coronary artery bypass grafting (MAG, n = 5580; LITA+SVG, n = 14 496) in the province of British Columbia, Canada, from January 2000 to December 2014, with follow-up to December 2015. We performed propensity-score analyses by weighting and matching and multivariable Cox regression to minimize treatment selection bias.

Exposures

Multiple arterial grafting or LITA+SVG.

Main Outcomes and Measures

Mortality, repeated revascularization, myocardial infarction, heart failure, and stroke.

Results

Of 5580 participants who underwent MAG, 586 (11%) were women and the mean (SD) age was 60 (8.7) years. Of 14 496 participants who underwent LITA+SVG, 2803 (19%) were women and the mean (SD) age was 68 (8.9) years. The median (interquartile range) follow-up time was 9.1 (5.1-12.6) years and 8.1 (4.5-11.7) years for the groups receiving MAG and LITA+SVG, respectively. Compared with LITA+SVG, MAG was associated with reduced mortality rates (hazard ratio [HR], 0.79; 95% CI, 0.72-0.87) and repeated revascularization rates (HR, 0.74; 95% CI, 0.66-0.84) in 15-year follow-up and reduced incidences of myocardial infarction (HR, 0.63; 95% CI, 0.47-0.85) and heart failure (HR, 0.79; 95% CI, 0.64-0.98) in 7-year follow-up. The long-term benefits were coherent by all 3 statistical methods and persisted among patient subgroups with diabetes, obesity, moderately impaired ejection fraction, chronic obstructive pulmonary disease, peripheral vascular disease, or renal disease. Multiple arterial grafting was not associated with increased morbidity or mortality rates at 30 days overall or within patient subgroups.

Conclusions and Relevance

Compared with LITA+SVG, MAG is associated with reduced mortality, repeated revascularization, myocardial infarction, and heart failure among patients with multivessel disease who are undergoing coronary artery bypass grafting without increased mortality or other adverse events at 30 days. The long-term benefits consistently observed across multiple outcomes and subgroups support the consideration of MAG for a broader spectrum of patients who are undergoing coronary artery bypass grafting in routine practice.

Falling hospital and postdischarge mortality following CABG in New South Wales from 2000 to 2013

Objectives

To describe changes in mortality among patients undergoing coronary artery bypass grafting (CABG) in New South Wales (NSW) Australia from 2000 to 2013.

Methods

Patients undergoing CABG were identified from the NSW Admission Patient Data Collection (APDC) registry, linked to the NSW state-wide death registry database. Changes in all-cause mortality over time were observed following stratification of the study cohort into two year groups.

Results

We identified 54 767 patients undergoing CABG during the study period. The risk profile of patients increased over time with significant increases in age, comorbidities and concomitant valve surgery (all p < 0.0001). During a median follow-up period of 6 years, a total 12 161 (22.2%) of patients had died. Survival curves and adjusted analyses showed a steady fall in mortality rate: those operated on during 2012–2013 had 40 % lower mortality than those operated on during 2000–2001 (HR 0.61; 95% CI 0.53 to 0.69). This was contributed to both by a fall in mortality both in hospital (HR 0.48, 95% CI 0.37 to 0.62) and postdischarge (HR 0.73; 95% CI 0.61 to 0.86).

Conclusions

We report a consistent reduction in medium-term mortality among a large unselected cohort of NSW patients undergoing CABG between 2000 and 2013. This fall is attributable both to an improvement in outcomes in hospital and in the postdischarge period.

Radial Artery Versus Saphenous Vein Grafts in Coronary Artery Bypass Surgery: a Literature Review

PURPOSE OF REVIEW

Coronary artery bypass grafting is a preferred strategy for complete coronary revascularization in patients who have multi-vessel coronary artery disease, left ventricular dysfunction, and/or diabetes. Both arterial (internal thoracic artery/radial artery) and venous grafts are utilized to bypass the obstruction in native vessels. Despite having radial arterial grafts as a preferred second conduit for bypass, venous grafts are more commonly used.

RECENT FINDINGS

We review the existing literature and report the preferred conduit based on a recently published meta-analysis of 6 randomized controlled trials. The analysis concluded that radial artery grafts are associated with fewer adverse cardiac events and better graft patency at 5 years of follow-up. Although saphenous vein grafting is the most commonly used conduit in addition to ITA, current data suggests that total arterial bypass (using RA conduit in addition to ITA) may be the better strategy. Both the US and European consensus guidelines advocate for the use of arterial over SV grafting for most patients.

State-of-the-Art Coronary Artery Bypass Grafting: Patient Selection, Graft Selection, and Optimizing Outcomes

Despite the progressive expansion of clinical indications for percutaneous coronary intervention and the increasingly high risk profile of referred patients, coronary artery bypass grafting (CABG) remains the mainstay in multivessel disease, providing good long-term outcomes with low complication rates. Multiple arterial grafting, especially if associated with anaortic techniques, might provide the best longer-term outcomes. A surgical approach individualized to the patients' clinical and anatomic characteristics, and surgeon and team experience, are key to excellent outcomes. Current evidence regarding patient selection, indications, graft selection, and potential strategies to optimize outcomes in patients treated with CABG is summarized.

Long-term outcomes of multiple and single arterial off-pump coronary artery bypass grafting

BACKGROUND

To compare the clinical outcomes between multiple arterial (MA) and single arterial (SA) off-pump coronary artery bypass grafting (OPCAB) when applied to left main coronary disease or three-vessel disease.

METHODS

A total of 537 patients with left main coronary disease or three-vessel disease underwent MA OPCAB (n=114) or SA OPCAB (n=423) in our center from January 2006 to December 2008. The propensity score matching (PSM) was used to obtain the risk-adjusted outcome. Both the perioperative and long-term results were analyzed.

RESULTS

The median follow-up time was 117 months (interquartile range, 110 to 128 months). There was no statistical difference in postoperative mortality and the volume of drainage. The intensive care unit (ICU) length of stay (LOS) of the MA group was shorter than that of the SA group {1 [1-2] vs. 2 [1-3], P=0.001). In the long term, the mortality (5.7% vs. 17.5%, P=0.006), cardiac mortality (1.0% vs. 8.8%, P=0.008), fatal myocardial infarction (MI) rate (0.0% vs. 6.1%, P=0.015) and incidence of readmission for heart failure (19.8% vs. 37.7%, P=0.003) were lower in the MA group than in the SA group. The distributions of NYHA class (P<0.001) and CCS class (P<0.001) were better in the MA group than in the SA group. There was no significant difference in other outcomes. These results were consistent with the K-M curves of freedom from the adverse events.

CONCLUSIONS

MA OPCAB was as safe as SA OPCAB, providing better perioperative recovery and better long-term clinical outcomes in the treatment of left main coronary disease or three-vessel disease.

Coronary Artery Bypass Surgery in Brazil: Analysis of the National Reality Through the BYPASS Registry

INTRODUCTION

Coronary artery bypass grafting (CABG) is the most frequently performed heart surgery in Brazil. Recent international guidelines recommend that national societies establish a database on the practice and results of CABG. In anticipation of the recommendation, the BYPASS Registry was introduced in 2015.

OBJECTIVE

To analyze the profile, risk factors and outcomes of patients undergoing CABG in Brazil, as well as to examine the predominant surgical strategy, based on the data included in the BYPASS Registry.

METHODS

A cross-sectional study of 2292 patients undergoing CABG surgery and cataloged in the BYPASS Registry up to November 2018. Demographic data, clinical presentation, operative variables, and postoperative hospital outcomes were analyzed.

RESULTS

Patients referred to CABG in Brazil are predominantly male (71%), with prior myocardial infarction in 41.1% of cases, diabetes in 42.5%, and ejection fraction lower than 40% in 9.7%. The Heart Team indicated surgery in 32.9% of the cases. Most of the patients underwent cardiopulmonary bypass (87%), and cardioplegia was the strategy of myocardial protection chosen in 95.2% of the cases. The left internal thoracic artery was used as a graft in 91% of the cases; the right internal thoracic artery, in 5.6%; and the radial artery in 1.1%. The saphenous vein graft was used in 84.1% of the patients, being the only graft employed in 7.7% of the patients. The median number of coronary vessels treated was 3. Operative mortality was 2.8%, and the incidence of cerebrovascular accident was 1.2%.

CONCLUSION

CABG data in Brazil provided by the BYPASS Registry analysis are representative of our national reality and practice. This database constitutes an important reference for indications and comparisons of therapeutic procedures, as well as to propose subsequent models to improve patient safety and the quality of surgical practice in the country.

Comparison of cardiovascular risk factors among coronary artery bypass graft patients in 2010 and 2016: A single-center study in Guilan province, Iran

BACKGROUND

There has been a change in the risk factor profile of patients with coronary artery disease (CAD) in the western world. We sought to compare the risk factor profile of patients undergoing coronary artery bypass graft (CABG) surgery in northern part of Iran in 2010 and 2016.

METHODS

In a cross-sectional study, medical records of 296 CABG patients in 2010 and 500 patients in 2016 were collected from a referral university hospital in Guilan province, Iran. We compared the risk factor profile using chi-square test or independent t-test as needed in the two time points, 2010 and 2016.

RESULTS

The age of CABG patients significantly decreased from 62.49 ± 8.05 to 58.09 ± 9.20 over time. The frequency of hypertension (HTN) (66.2% vs. 59.1%, P = 0.045), diabetes mellitus (DM) (51.8% vs. 43.6%, P = 0.025), smoking (35.6% vs. 28.0%, P = 0.028), and patients with multimorbidity (31.8% vs. 26.7%, P = 0.001) increased in the second period compared to the first period of study. Whereas, the prevalence of hypercholesterolemia and positive family history of coronary heart disease (CHD) remained stable over time (49.6% vs. 49.0%, P = 0.870; 10.5% vs. 11.1%, P = 0.810, respectively).

CONCLUSION

We observed a dramatic increase in DM, HTN, and cigarette smoking as well as the multimorbidity prevalence in 2016 compared to 2010. Even with considering all study limitations, primary and secondary prevention program to decrease cardiovascular disease is required.

Pretreatment with glucose-insulin-potassium improves ventricular performances after coronary artery bypass surgery: a randomized controlled trial

Heart failure is the main cause of poor outcome following open heart surgery and experimental studies have demonstrated that glucose–insulin–potassium (GIK) infusion exerts cardioprotective effects by reducing myocardial ischemia–reperfusion injuries. This randomized controlled trial was designed to assess the effects of GIK on left ventricular function in moderate-to-high risk patients undergoing on-pump isolated coronary artery bypass surgery (CABGS), or combined with aortic valve replacement. The primary outcomes were the effects of GIK on two- and three-dimensional left ventricular ejection fraction (2D and 3D-LVEF), and on transmitral flow propagation velocity (Vp), that occurred between the pre- and post-CPB periods. GIK administration was associated with favorable interaction effects (p < 0.001) on 2D-LVEF, 3D-LVEF and Vp changes over the study periods. In GIK pretreated patients (N = 54), 2-D and 3D-LVEF and Vp increased slightly during surgery (mean difference [MD] + 3.5%, 95% confidence interval [95% CI] − 0.2 to 7.1%, MD + 4.0%, 95% CI 0.6–7.4%, and MD + 22.2%, 95% CI 16.0–28.4%, respectively). In contrast, in the Placebo group (N = 46), 2D-and 3D-LVEF, as well as Vp all decreased after CPB (MD − 7.5% [− 11.6 to − 3.4%], MD − 12.0% [− 15.2 to − 8.8%] and MD − 21.3% [− 25.7 to − 16.9%], respectively). In conclusion, the administration of GIK resulted in better preservation of systolic and diastolic ventricular function in the early period following weaning from CPB.

Coronary Revascularization in High-Risk Stable Patients With Significant Comorbidities: Challenges in Decision-Making

PURPOSE OF REVIEW

There is a growing cohort of complex high-risk patients with stable ischemic heart disease (SIHD) who present for coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI). These patients are older, have complex coronary disease, and a substantial comorbidity burden including frailty. The procedural risks and outcomes of CABG and PCI in these patients are more difficult to assess based on the available literature, which has generally studied a younger population with a lower comorbidity burden.

RECENT FINDINGS

There have been initiatives to recalibrate and expand risk models derived from procedural registries to inform the care of complex higher-risk patients, including patients "turned down" for CABG. There is greater recognition of the need for improved assessment of risk, quality, and benefits of coronary revascularization in higher-risk SIHD patients with a substantial comorbidity burden. Clinicians and patients should be aware that there are significant evidence gaps regarding revascularization in complex high-risk patients. The limitations of procedural-derived risk scores should be understood when presenting treatment options. Future randomized controlled trials and expanded registries are greatly desired and should be achievable. Meanwhile, a multidisciplinary heart team approach should be employed for proper decision-making.

Saphenous Vein Graft Aneurysm: A Case-Based Review of Percutaneous Management

SVG aneurysms are relatively rare clinical entities most often encountered discovered as an incidental finding in patients with prior CABG surgery. There is a substantial risk of complications including rupture and death, thus surgical or percutaneous management may be considered in particular in symptomatic patients. Here, three cases are presented highlighting various percutaneous management options and considerations, including covered stent placement, coil occlusion, and a combined approach with the use of a peripheral covered stent. Intervention within this patient population lacks large population long-term outcomes and as such should be performed carefully by experienced operators, often the guidance of a Heart Team based approach.

The effect of high-dose nitroglycerin on the cerebral saturation and renal function in cardiac surgery: A propensity score analysis

BACKGROUND

The aim of the study was to evaluate the effects of high-dose nitroglycerine administered during cardiopulmonary bypass on the intraoperative cerebral saturation and postoperative serum creatinine concentration in cardiac surgery.

METHODS

In a retrospective cohort study, a total of 239 patients undergoing cardiac surgery with cardiopulmonary bypass at a tertiary medical center were included. General anesthesia consisted of volatile anesthetic and either intravenous loading of high-dose nitroglycerin (infusion rate 10 to 20 mg·h with a total dose of ≥0.5 mg·kg) starting from rewarming of cardiopulmonary bypass throughout the end of the surgery (NTG group; N = 96) or without high-dose nitroglycerin (control group; N = 143). Data for intraoperative cerebral saturation and serum creatinine concentrations before and after cardiac surgery were collected. Propensity score method was used to adjust for potential confounders.

RESULTS

Patients receiving high-dose nitroglycerin had significantly lower mean arterial pressure and hematocrit levels during and after cardiopulmonary bypass. The risk of intraoperative cerebral desaturation was left-sided 23.9% versus 38.5% (p = 0.023), right-sided 28.1% versus 35.7% in the NTG and control groups, respectively. The risk of new-onset stroke and postoperative dialysis was 2.1% versus 6.3% and 1.0% versus 3.5% in the NTG and control groups, respectively.

CONCLUSION

An infusion of high-dose nitroglycerin initiating at rewarming of cardiopulmonary bypass and throughout the postbypass interval may induce hypotension and hemodilution in cardiac surgical patients. Cerebral saturation and renal function were well maintained without increasing the risk of stroke and renal replacement therapy after cardiac surgery with cardiopulmonary bypass.

Clopidogrel versus Ticagrelor for Secondary Prevention after Coronary Artery Bypass Grafting

We sought to evaluate the outcomes of postoperative three-month dual antiplatelet therapy in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) following off-pump coronary artery bypass grafting (OPCAB) with exclusively arterial grafts. Between 2013–2016, dual antiplatelet therapy (DAPT) with either aspirin + clopidogrel (ASA + CPD group, n = 100) or aspirin + ticagrelor (ASA + TCG group, n = 169) was prescribed postoperatively in 269 NSTE-ACS patients after total arterial OPCAB. Patients with indications for other oral anticoagulants were excluded from the study. Three-month DAPT was completed in 259 patients (96%); ASA + CPD group (n = 94) vs. ASA + TCG group (n = 165). A one-to-one propensity score matching was performed. Unadjusted comparison between the groups showed no significant difference in overall survival (P = 0.253) and composite outcome of major adverse cerebrovascular and cardiovascular event (MACCE) and major bleeding (P = 0.276). The rate of freedom from composite outcome at one year in the ASA + CPD and ASA + TCG groups was 91 ± 3% and 93 ± 2%, respectively. In multivariable analysis, being in the ASA + TCG group did not increase the risk of the composite outcome of MACCE and major bleeding (P = 0.972, hazard ratio: 1.0, 95% confidence interval: 0.4–2.3). Propensity score-matched comparison (76 pairs) showed no significant difference in the overall survival (P = 0.423) and composite outcome between the groups (P = 0.442). In the setting of exclusive arterial grafting, post-OPCAB three-month DAPT showed acceptable outcomes in patients with NSTE-ACS. There was no significant difference in overall survival or composite outcome of MACCE and major bleeding between the ASA + CPD and ASA + TCG groups.

Validation of the Fitbit Flex in an Acute Post-Cardiac Surgery Patient Population

Purpose: This study examined the validity of the Fitbit Flex activity monitor for step count and distance walked among post-cardiac surgery patients. Method: Participants (n=20) from a major urban cardiac surgery centre were recruited 1-2 days before hospital discharge. The Fitbit Flex step count and distance walked outputs and video recording of each participant performing the 6-minute walk test were collected. Fitbit Flex output was compared with criterion measures of manual step count obtained from the video recording and manual measurement of distance walked. Statistical analysis compared the output and criterion measures using paired sample t-tests, Pearson correlation coefficients, Lin's concordance correlations, and Bland-Altman plots. Sub-analysis compared slower walking (<0.8 m/s; n=11) and faster walking (≥0.8 m/s; n=8) group speeds (1 participant was excluded from analysis). Results: Steps counted and distance walked were significantly different between the Fitbit Flex outputs and criterion measures (p<0.05). The Fitbit Flex steps counted and distance walked showed moderate association with manual measure steps counted (r=0.67) and distance walked (r=0.45). Lin's concordance coefficients revealed a lack of agreement between the Fitbit Flex and the criterion measurement of both steps counted (concordance correlation coefficient [CCC]=0.43) and distance walked (CCC=0.36). The percentage of relative error was -18.6 (SD 22.7) for steps counted and 25.4 (SD 45.8) for distance walked. Conclusions: The Fitbit Flex activity monitor was not a valid measure of step count and distance walked in this sample of post-cardiac surgery patients. The lack of agreement between outputs and criterion measures suggests the Fitbit Flex alone would not be an acceptable clinical outcome measure for monitoring walking progression in the early postoperative period.

Angiographic appearance of patent saphenous vein grafts more than 25 years after coronary artery bypass grafting

Nine patients with ten angiographical patent saphenous vein grafts (SVG) more than 25 years after coronary artery bypass grafting (CABG) at Kawasaki Medical School Hospital between 1976 and 1992 were reviewed. Patent SVG disease was assessed using the FitzGibbon classification, and clinical characteristics which might affect the longevity of SVG were retrospectively evaluated. The mean duration between surgery and current coronary angiography was approximately 30 years (25-35 years). There were two perfectly patent SVGs (FitzGibbon AI, 35 and 32 years after surgery), both of which were bypass grafts to the left anterior descending arteries (LAD). The other eight grafts exhibited some vein graft disease (BII:3, BIII:5). The sequential anastomosis was performed for 5 SVGs. The SVGs bypassed to the good run-off LAD, sequential bypass, strict medical management including cessation of smoking and body weight control may contribute to the slow progression of vein graft disease after CABG.

Coronary artery bypass grafting-fifty years of quality initiatives since Favaloro

Coronary artery bypass grafting (CABG) remains one of the most commonly performed major surgical procedures worldwide and the most common procedure performed by cardiac surgeons. Rene Favaloro is widely credited with recognizing the true potential of CABG and subsequently popularizing the technique in a broad manner. Since the era of Favaloro in the late 1960s, the evolution of CABG can be understood through a series of quality initiatives that have defined which patients can benefit from the procedure and via which technique(s) they will derive the greatest benefit. Herein, we will review some of the key developments in CABG over the last 50 years with a focus on ongoing quality initiatives that will continue to refine the optimal applications and outcomes of CABG for the next 50 years.

Is there a role for fractional flow reserve in coronary artery bypass graft (CABG) planning?

The concept of significant lesions has substantially evolved over the last decade. With growing evidence for use of fractional flow reserve (FFR) as a determinant of lesion-specific ischemia and its superiority to angiography-guided revascularization and medical therapy, the field of percutaneous revascularization has shifted to rely exclusively on FFR instead of luminal stenosis alone in guiding revascularization. This transition to physiological assessment has not yet made it to the realm of surgical revascularization. FFR-guided therapy has been shown to be superior to angiography-guided therapy mainly by safe deferral of about 1/3rd of lesions, leading to less periprocedural events and better outcomes. Is it possible that utilization of FFR-guided CABG would lead to less complicated procedures, shorter operating times, more frequent off pump CABG procedures and more hybrid procedures? Can FFR-guided CABG improve the cardiovascular outcomes as compared to current standard of practice? In the following paragraphs we review the concept of FFR, the evidence behind FFR-guided therapy, the emerging data regarding use FFR-guided CABG and discuss where the revascularization field is headed.

Percutaneous coronary intervention versus coronary artery bypass grafting: where are we after NOBLE and EXCEL?

PURPOSE OF REVIEW

The publication of the NOBLE and EXCEL trials, with seemingly conflicting results, brought into question whether percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) is better for low-risk patients with left main coronary artery stenosis (LMCAS). This review appraises the methods and results of NOBLE and EXCEL, contextualizes them within the literature, and determines how they may affect clinical practice.

RECENT FINDINGS

We appraised the trials and describe differences in methodology and results. NOBLE recruited primarily isolated LMCAS, and found that CABG was superior to PCI. EXCEL's population included patients LMCAS in the context of multivessel CAD, and found PCI and CABG were comparable. Both trials enrolled young patients with few comorbidities, and there was more protocol-mandated consistency in the procedural techniques and medical therapy of patients receiving PCI.

SUMMARY

The generalizability of these trials is limited by the use of young, healthy patients at highly skilled centres that rarely reflect typical clinical practice. If these studies are to maintain relevance, trialists must address the lack of protocolization of surgical interventions and inconsistent medical therapies. Unfortunately, the limitations of NOBLE and EXCEL mean that we are no closer to answering the question of what is the optimal treatment for patients with LMCAS.

Bilateral internal thoracic arteries: what is the State of the ART?

PURPOSE OF REVIEW

To provide a broad overview of the current state of knowledge of coronary artery bypass grafting with bilateral internal thoracic artery (BITA).

RECENT FINDINGS

There exists a large body of literature from mostly observational studies supporting the use of BITA in patients undergoing coronary artery bypass grafting but selection bias is a major issue with nonrandomized data. The precise method of BITA use does not appear to impact graft patency nor clinical outcomes - in other words, BITA in any configuration appears to be protective. The major downside is the increased risk of sternal complications, which can be mitigated with sternal-sparring adjuncts. The 5-year interim results of the landmark Arterial Revascularization Trial comparing BITA versus single internal thoracic artery did not show a clinical benefit for BITA but the end-of-trial results are pending. Despite wide guideline support for BITA use, uptake in the surgical community remains low and this is likely because of technical and institutional barriers.

SUMMARY

The published literature thus far supports surgical revascularization with BITA and we eagerly await the 10-year Arterial Revascularization Trial results. The general consensus is that a greater proportion of surgical revascularization should be performed using BITA.

The Impact of the Medicaid Healthcare-Associated Condition Program on Mediastinitis Following Coronary Artery Bypass Graft

OBJECTIVEIn 2012, the Centers for Medicare and Medicaid Services expanded a 2008 program that eliminated additional Medicare payment for mediastinitis following coronary artery bypass graft (CABG) to include Medicaid. We aimed to evaluate the impact of this Medicaid program on mediastinitis rates reported by the National Healthcare Safety Network (NHSN) compared with the rates of a condition not targeted by the program, deep-space surgical site infection (SSI) after knee replacement.DESIGNInterrupted time series with comparison group.METHODSWe included surveillance data from nonfederal acute-care hospitals participating in the NHSN and reporting CABG or knee replacement outcomes from January 2009 through June 2017. We examined the Medicaid program's impact on NHSN-reported infection rates, adjusting for secular trends. The data analysis used generalized estimating equations with robust sandwich variance estimators.RESULTSDuring the study period, 196 study hospitals reported 273,984 CABGs to the NHSN, resulting in 970 mediastinitis cases (0.35%), and 294 hospitals reported 555,395 knee replacements, with 1,751 resultant deep-space SSIs (0.32%). There was no significant change in incidence of either condition during the study. Mediastinitis models showed no effect of the 2012 Medicaid program on either secular trend during the postprogram versus preprogram periods (P=.70) or an immediate program effect (P=.83). Results were similar in sensitivity analyses when adjusting for hospital characteristics, restricting to hospitals with consistent NHSN reporting or incorporating a program implementation roll-in period. Knee replacement models also showed no program effect.CONCLUSIONSThe 2012 Medicaid program to eliminate additional payments for mediastinitis following CABG had no impact on reported mediastinitis rates.Infect Control Hosp Epidemiol 2018;39:694-700.

Radial-Artery or Saphenous-Vein Grafts in Coronary-Artery Bypass Surgery

BACKGROUND

The use of radial-artery grafts for coronary-artery bypass grafting (CABG) may result in better postoperative outcomes than the use of saphenous-vein grafts. However, randomized, controlled trials comparing radial-artery grafts and saphenous-vein grafts have been individually underpowered to detect differences in clinical outcomes. We performed a patient-level combined analysis of randomized, controlled trials to compare radial-artery grafts and saphenous-vein grafts for CABG.

METHODS

Six trials were identified. The primary outcome was a composite of death, myocardial infarction, or repeat revascularization. The secondary outcome was graft patency on follow-up angiography. Mixed-effects Cox regression models were used to estimate the treatment effect on the outcomes.

RESULTS

A total of 1036 patients were included in the analysis (534 patients with radial-artery grafts and 502 patients with saphenous-vein grafts). After a mean (±SD) follow-up time of 60±30 months, the incidence of adverse cardiac events was significantly lower in association with radial-artery grafts than with saphenous-vein grafts (hazard ratio, 0.67; 95% confidence interval [CI], 0.49 to 0.90; P=0.01). At follow-up angiography (mean follow-up, 50±30 months), the use of radial-artery grafts was also associated with a significantly lower risk of occlusion (hazard ratio, 0.44; 95% CI, 0.28 to 0.70; P<0.001). As compared with the use of saphenous-vein grafts, the use of radial-artery grafts was associated with a nominally lower incidence of myocardial infarction (hazard ratio, 0.72; 95% CI, 0.53 to 0.99; P=0.04) and a lower incidence of repeat revascularization (hazard ratio, 0.50; 95% CI, 0.40 to 0.63; P<0.001) but not a lower incidence of death from any cause (hazard ratio, 0.90; 95% CI, 0.59 to 1.41; P=0.68).

CONCLUSIONS

As compared with the use of saphenous-vein grafts, the use of radial-artery grafts for CABG resulted in a lower rate of adverse cardiac events and a higher rate of patency at 5 years of follow-up. (Funded by Weill Cornell Medicine and others.).