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

Perioperative stroke: pathophysiology and management

Although perioperative stroke is uncommon during low-risk non-vascular surgery, if it occurs, it can negatively impact recovery from the surgery and functional outcome. Based on the Society for Neuroscience in Anesthesiology and Critical Care Consensus Statement, perioperative stroke includes intraoperative stroke, as well as postoperative stroke developing within 30 days after surgery. Factors related to perioperative stroke include age, sex, a history of stroke or transient ischemic attack, cardiac surgery (aortic surgery, mitral valve surgery, or coronary artery bypass graft surgery), and neurosurgery (external carotid-internal carotid bypass surgery, carotid endarterectomy, or aneurysm clipping). Concomitant carotid and cardiac surgery may further increase the risk of perioperative stroke. Preventive strategies should be individualized based on patient factors, including cerebrovascular reserve capacity and the time interval since the previous stroke.

Epidemiology of new-onset atrial fibrillation following coronary artery bypass graft surgery

OBJECTIVES

Postoperative atrial fibrillation (AF) following coronary artery bypass graft surgery (CABG) is significantly associated with reduced survival, but poor characterisation and inconsistent definitions present barriers to developing effective prophylaxis and management. We sought to address this knowledge gap.

METHODS

From 2002 to 2010, 11 239 consecutive patients without AF underwent isolated CABG at five sites. Clinical data collected for the Society of Thoracic Surgeons (STS) Database were augmented with details on AF detected via continuous in-hospital ECG/telemetry monitoring to assess new-onset post-CABG AF (adjusted for STS risk of mortality); time to first AF; durations of first and longest AF episodes; total in-hospital time in AF; number of in-hospital AF episodes; operative mortality; stroke; discharge in AF; and length of stay (LOS).

RESULTS

Unadjusted incidence of new-onset post-CABG AF was 29.5%. Risk-adjusted incidence was 33.1% and varied little over time (P=0.139). Among 3312 patients with post-CABG AF, adjusted median time to first AF was 52 (IQR: 48-55) hours; mean (SD) duration of first and longest events were 7.2 (5.3,9.1) and 13.1 (10.4,15.9) hours, respectively, and adjusted median total time in AF was 22 (IQR: 18-26) hours. Adjusted rates of operative mortality, stroke and discharge in AF did not vary significantly over time (P=0.156, P=0.965 and P=0.347, respectively). LOS varied (P=0.035), but in no discernible pattern.

CONCLUSIONS

Each year, ~800 000 people undergo CABG worldwide; >264 000 will develop post-CABG AF. Onset is typically 2-3 days post-CABG and episodes last, on average, several hours. Effective prophylaxis and management is urgently needed to reduce associated risks of adverse outcomes.

Total arterial revascularization in patients with acute myocardial infarction - feasibility and outcomes

BACKGROUND

In acute situations such as acute myocardial infarction (AMI) with indication for coronary artery bypass grafting (CABG), total arterial revascularization (TAR) is often rejected in favour of saphenous vein (SV) grafting, which is assumed to allow for quicker vessel harvesting, a simpler anastomosis technique, and thus quicker revascularization and fewer bleeding complications. The aim of this study was to evaluate whether reluctance to apply TAR in AMI is still justified from a technical point of view in the current era and whether superiority of TAR results is also evident in emergency patients with AMI undergoing CABG.

METHODS

In this retrospective analysis of 434 consecutive patients undergoing CABG for AMI with either TAR or with a combination of one internal mammary artery and SV grafts between 2008 and 2014, procedural data, short-term and mid-term outcome were compared. Propensity score matching of the groups was performed.

RESULTS

After propensity score matching, 250 patients were included in the analysis (TAR group: n = 98; SV group n = 152). The procedural time (TAR group: 211 min vs. SV group: 200 min, p = 0.46) did not differ between the groups. Erythrocyte transfusion rates were higher in the SV group (76% vs. 57%; p < 0.001). Rates of re-exploration for bleeding did not differ. Thirty-day mortality rates were comparable (TAR group: 3.4% vs. SV group: 4.5%, p = 0.68). Kaplan-Meier analysis until 7 years postoperatively revealed a tendency for improved survival after TAR (75% vs. 62%; log-rank p = 0.12).

CONCLUSION

TAR neither impairs rapid revascularization nor reduces its safety in patients with AMI. It may result in improved long-term outcome and should be preferred in the clinical setting of AMI.

In Situ Skeletonized Right Internal Mammary Artery Bypass Grafting to Left Anterior Descending Artery

This study aimed to evaluate the feasibility and the mid-term efficacy of an in situ skeletonized right internal mammary artery (IMA) bypass grafting to a left anterior descending artery (LAD), and to determine risk factors for IMA graft failure in a single-center study.From January 2012 to December 2015, 189 patients (173 males, 50.6 ± 6.0 years old) undergoing first isolated coronary artery bypass grafting surgery with the in situ skeletonized right IMA grafting to the LAD were included in this study. Baseline characteristics, peroperative data, and follow-up outcomes were investigated and analyzed.The length of the in situ skeletonized right IMA grafts was 18.6 ± 1.2 cm (17.0-22.0 cm). Intraoperative graft flow of the in situ skeletonized right IMA grafting to LAD was 42 ± 9 mL/minute (18-72 mL/minute) associated with measured pulsatility index of 0.8-4.3. In-hospital mortality was 0.5%. Postoperative morbidity included acute myocardial infarction (0.5%), stroke (0.5%), and deep sternal wound infections (1.1%). The mid-term survival was 97.2% and the incidence of repeat revascularization was 0.6%. The patency rate of the in situ skeletonized right IMA grafting to the LAD was 97.1% by computed tomography angiography examination during the follow-up period of 23.2 ± 9.7 months. Additionally, logistic regression analysis showed that intraoperative graft flow had an independent influence on the risk of the mid-term right IMA graft failure.The strategy of the in situ skeletonized right IMA grafting to the LAD is feasible and effective. Intraoperative graft flow was an independent risk factor for the mid-term right IMA graft failure.

National Trends and Geographic Variation in Bilateral Internal Mammary Artery Use in the United States

BACKGROUND

The goal of this study was to characterize the adoption rate and regional variation in bilateral internal mammary artery (BIMA) use during coronary artery bypass grafting (CABG) in the United States.

METHODS

Observational study of 100% sample of fee-for-service Medicare beneficiaries aged 65 years or older, continuously enrolled in Parts A and B from 2009 to 2014 (n = 162,860,439). Rates of beneficiaries receiving a BIMA versus single internal mammary artery (SIMA) during CABG are expressed per 1,000 beneficiaries and aggregated by Hospital Referral Region (HRR). An HRR is a validated unit for quantifying regional variation in health care.

RESULTS

The absolute national rate of BIMA use declined during the study period from 0.21 claims per 1,000 beneficiaries in 2009 to 0.13 in 2014 (p < 0.001). When indexed to overall CABG volume, no change was seen in the frequency of BIMA use over time (p = 0.883). SIMA use ranged from 1.3 to 8.5 claims per 1,000 Medicare beneficiaries, whereas BIMA use ranged from 0 to 1.5 (p < 0.001). A significant correlation was found between regional volume of SIMA use and likelihood of BIMA use (correlation coefficient 0.673, p < 0.001). Although both SIMA and BIMA use correlated with regional volume of diagnostic cardiac catheterization, the correlation was stronger for SIMA use (correlation coefficient 0.962 versus 0.682, p < 0.001).

CONCLUSIONS

Over the past 5 years, no growth was seen in BIMA use among Medicare beneficiaries, and the frequency of BIMA use during CABG remained low. There was significant regional variation in BIMA use, however, which demonstrates opportunity for continued growth of BIMA grafting.

Bilateral Internal Mammary Artery Use Can Be Safely Taught Without Increasing Morbidity or Mortality

BACKGROUND

Evidence shows a likely survival benefit with the use of bilateral internal mammary arteries (BIMA) compared with a single internal mammary artery (SIMA). Nonetheless, BIMA use is often not used or taught because of a perceived increase in operative time and complexity. This study aimed to evaluate operative time, morbidity, and mortality in both resident and nonresident cases using BIMA compared with SIMA.

METHODS

Consecutive patients undergoing isolated coronary artery bypass grafting (October 2012 to April 2015) at a single institution were reviewed. Cases were stratified on the basis of the use of SIMA versus BIMA and resident teaching versus nonresident teaching cases. Primary outcomes included operative time, postoperative morbidity, and mortality.

RESULTS

A total of 416 patients were identified; 335 of 416 (81%) patients received a SIMA, and 81 of 416 (19%) patients received BIMA. A total of 184 of 416 (44%) were resident cases: 143 of the 335 (43%) SIMA cases and 41 of the 81 (51%) BIMA cases. Use of BIMA in resident cases was associated with a longer operative and cardiopulmonary bypass (CPB) time than resident SIMA cases, but this increased time did not affect morbidity or mortality. Use of SIMA versus BIMA in nonresident cases had no significant difference on total operative time, CPB time, postoperative morbidity, or mortality. Overall, operative and 1-year mortality rates were similar in the SIMA and BIMA groups (SIMA: 1.2%, 1.8%, respectively; BIMA: 0%, 0%, respectively; p = NS).

CONCLUSIONS

In the hands of an experienced surgeon, BIMA use can be effectively performed without an increase in operative or CPB time. In resident teaching cases, BIMA use may increase operative time, but it can be safely taught without affecting morbidity or mortality.

Cardioprotection mediated by exosomes is impaired in the setting of type II diabetes but can be rescued by the use of non-diabetic exosomes in vitro

Many patients with ischaemic heart disease also have diabetes. As myocardial infarction is a major cause of mortality and morbidity in these patients, treatments that increase cell survival in response to ischaemia and reperfusion are needed. Exosomes—nano‐sized, lipid vesicles released from cells—can protect the hearts of non‐diabetic rats. We previously showed that exosomal HSP70 activates a cardioprotective signalling pathway in cardiomyocytes culminating in ERK1/2 and HSP27 phosphorylation. Here, we investigated whether the exosomal cardioprotective pathway remains intact in the setting of type II diabetes. Exosomes were isolated by differential centrifugation from non‐diabetic and type II diabetic patients, from non‐diabetic and Goto Kakizaki type II diabetic rats, and from normoglycaemic and hyperglycaemic endothelial cells. Exosome size and number were not significantly altered by diabetes. CD81 and HSP70 exosome markers were increased in diabetic rat exosomes. However, exosomes from diabetic rats no longer activated the ERK1/2 and HSP27 cardioprotective pathway and were no longer protective in a primary rat cardiomyocytes model of hypoxia and reoxygenation injury. Hyperglycaemic culture conditions were sufficient to impair protection by endothelial exosomes. Importantly, however, exosomes from non‐diabetic rats retained the ability to protect cardiomyocytes from diabetic rats. Exosomes from diabetic plasma have lost the ability to protect cardiomyocytes, but protection can be restored with exosomes from non‐diabetic plasma. These results support the concept that exosomes may be used to protect cardiomyocytes against ischaemia and reperfusion injury, even in the setting of type II diabetes.

Favourable long-term outcome after coronary artery bypass grafting in a nationwide cohort

OBJECTIVES

In a nationwide cohort, we analyzed long-term outcome following coronary artery bypass grafting, using the combined strategy of left internal mammary artery to the left anterior descending artery and saphenous vein as secondary graft to other coronary targets.

METHODS

1,507 consecutive patients that underwent myocardial revascularization during 2001-2012 in Iceland. Mean follow-up was 6.8 years. Major adverse cardiac and cerebrovascular events were depicted using the Kaplan-Meier method. Cox-regression was used to define risk factors. Relative survival was estimated by comparing overall survival to the survival of Icelanders of the same age and gender.

RESULTS

Mean age was 66 years, 83% were males, mean EuroSCOREst was 4.5, and 23% of the procedures were performed off-pump. At 5 years, 19.7% had suffered a major adverse cardiac or cerebrovascular event, 4.5% a stroke, 2.2% myocardial infarction, and 6.2% needed repeat revascularization. Overall 5-year survival was 89.9%, with a relative survival of 0.990. Independent predictors of major adverse cardiac and cerebrovascular events were left ventricular ejection fraction ≤30%, a previous history of percutaneous coronary intervention, chronic obstructive lung disease, chronic kidney disease, diabetes, and old age. The same variables and an earlier year of operation were predictors of long-term mortality.

CONCLUSIONS

The long-term outcome following myocardial revascularization, using the left internal mammary artery and the great saphenous vein as conduits, is favourable and improving. This is reflected by the 5-year survival of 89.9%, deviating minimally from the survival rate of the general Icelandic population, together with a freedom from major adverse cardiac and cerebrovascular events of 80.3%.

Worldwide Trends in Multi-arterial Coronary Artery Bypass Grafting Surgery 2004-2014: A Tale of 2 Continents

Recent evidence shows that multi-arterial coronary artery bypass grafting (MABG) based on bilateral internal thoracic (BITA) or left internal thoracic (LITA) and radial artery (RA) improves long-term outcomes compared with single arterial coronary artery bypass grafting (SABG) (LITA + saphenous vein graft). How this evidence affected the worldwide use of MABG, if at all, is not well defined. Accordingly, we report 10-year temporal trends of MABG utilization from 2 continents. A study population of 1,683,434 non-emergent, primary, isolated LITA-based coronary artery bypass grafting (CABG) (≥2 grafts) patients was derived from the Society of Thoracic Surgeons (STS) (1,307,528 (79.5%) of 1,644,388 isolated CABG; total 1179 centers) and the Australia New Zealand Cardiothoracic (ANZ) Databases (34,213 (87%) of 39,046 isolated CABG; 24 centers) between 2004 and 2014. Patients were excluded based on the following: (1) no LITA, (2) if arterial grafts were other than RA or ITA, or (3) if grafting data were missing. The 3 MABG groups were LITA + RA, BITA, and BITA + RA, each with or without supplemental vein grafts. Grafting trends and their associated patient demographics were analyzed. SABG (89.3% STS, 51.4% ANZ) was the most common grafting strategy. MABG was most frequently accomplished by LITA + RA: (STS: 6.1%; ANZ: 42.6%), followed by BITA: (STS: 4.1%; ANZ: 4.3%), while ≥3 (BITA + RA) was rare in the STS (0.5%), but more common in ANZ (5.9%). In the STS, between 2004 and 2014, SABG rates systematically increased from 85.2% to 91.7%, BITA grafting was essentially unchanged from 3.6% to 4.3%, while RA use decreased systematically from 10.5% to 3.7%. In the ANZ, SABG rates increased from 17.3% to 51.4%, BITA grafting decreased from 6.3% to 3.6%, while RA grafting decreased from 65.8% to 39.0%. Compared with SABG patients, BITA patients were younger (STS: median age 59 vs 66, P < 0.001; ANZ: mean age 62 vs 68, P < 0.001), predominately male (STS: 84% vs 73%, P < 0.001; ANZ: 86% vs 79%, P < 0.001), less obese (body mass index >30 kg/m²) in STS (37% vs 42%, P < 0.001), more obese in ANZ (33% vs 32%, P = 0.001), and less diabetic (STS: 26% vs 43%, P < 0.001; ANZ: 25% vs 37%, P < 0.001), whereas RA patients were intermediate in age (STS: 61; ANZ: 65), in male sex (STS: 82%; ANZ: 81%), in the prevalence of diabetes (STS: 40%; ANZ: 34%), and were most obese (STS: 47%; ANZ: 34%). A decade-long analysis of STS data reveals a counterintuitive decline in the use (driven by decreasing RA use) of MABG: a potentially superior grafting strategy compared with SABG. In contra distinction, the smaller but growing ANZ data document a distinctly different CABG practice pattern, with a higher MABG utilization rate, but a similarly declining RA use. The reasons for these practice patterns and declining MABG are likely diverse and require further assessment.

Management and Prevention of Saphenous Vein Graft Failure: A Review

Coronary artery bypass grafting (CABG) remains a vital treatment for patients with multivessel coronary artery disease (CAD), especially diabetics. The long-term benefit of the internal thoracic artery graft is well established and remains the gold standard for revascularization of severe CAD. It is not always possible to achieve complete revascularization through arterial grafts, necessitating the use of saphenous vein grafts (SVG). Unfortunately, SVGs do not have the same longevity, and their failure is associated with significant adverse cardiac outcomes and mortality. This paper reviews the pathogenesis of SVG failure, highlighting the difference between early, intermediate, and late failure. It also addresses the different surgical techniques that affect the incidence of SVG failure, as well as the medical and percutaneous prevention and treatment options in contemporary practice.

Radial Artery as a Coronary Artery Bypass Conduit: 20-Year Results

BACKGROUND

There is a lack of evidence for the choice of the second conduit in coronary surgery. The radial artery (RA) is a possible option, but few data on very-long-term outcomes exist.

OBJECTIVES

This study describes 20-year results of RA grafts used for coronary artery bypass grafting and the effects of RA removal on forearm circulation.

METHODS

We report the results of the prospective 20-year follow-up of the first 100 consecutive patients who received the RA as a coronary bypass conduit at our institution.

RESULTS

Follow-up was 100% complete. There were 64 deaths, 23 (35.9%) from cardiovascular causes. Kaplan-Meier 20-year survival was 31%. Of the 36 survivors, 33 (91.6%) underwent RA graft control at a mean of 19.0 ± 2.5 years after surgery. The RA was found to be patent in 24 cases (84.8% patency). In the overall population, probability of graft failure at 20 years was 19.0 ± 0.2% for the left internal thoracic artery (ITA), 25.0 ± 0.2% for the RA, and 55.0 ± 0.2% for the saphenous vein (p = 0.002 for RA vs. saphenous vein, 0.11 for RA vs. ITA, and p < 0.001 for ITA vs. saphenous vein). Target vessel stenosis >90%, but not location of distal anastomosis, significantly influenced long-term RA graft patency. No patients reported hand or forearm symptoms. The ulnar artery diameter was increased in the operated arm (2.44 ± 0.43 mm vs. 2.01 ± 0.47 mm; p < 0.05) and correlated with the peak systolic velocity of the second palmar digital artery (Pearson coefficient: 0.621; p < 0.05).

CONCLUSIONS

The 20-year patency rate of RA grafts is good, and not inferior to the ITA, especially when the conduit is used to graft a vessel with >90% stenosis. RA harvesting does not lead to hand or forearm symptoms, even at a very-long-term follow-up.

Pedicled Vein Grafts in Coronary Surgery: Perioperative Data From a Randomized Trial

BACKGROUND

Less-than-optimal long-term patency of the saphenous vein is one of the main obstacles for the success of coronary artery bypass grafting (CABG). Results from the IMPROVE-CABG trial has shown that harvesting the saphenous vein with a pedicle of perivascular tissue less than 5 mm while using manual distention provides comparable occlusion rates but significantly less intimal hyperplasia at early follow-up. The impact of pedicled veins on duration of operations, leg wound infections, and postoperative bleeding is unknown.

METHODS

One hundred patients undergoing first-time elective CABG were randomly assigned to conventional or pedicled vein harvesting. Perioperative and postoperative data were collected prospectively during the hospital stay and at follow-up.

RESULTS

Duration of extracorporeal circulation was significantly longer in the pedicled vein group (mean: 76 min versus 65 min, p = 0.006); however, no significant difference was found in the cross-clamp time. No significant difference was found in intraoperative vein graft flow, postoperative bleeding, or leg wound infections (4% in each group). No reoperations were due to vein graft bleeding.

CONCLUSIONS

Harvesting a pedicled vein provides comparable postoperative bleeding and leg wound infection rates in selected patients. The technique is associated with a slightly longer duration of extracorporeal circulation than harvesting conventional veins. Promising early results using the pedicled vein technique may contribute to a change in standard vein harvesting technique for CABG in selected patients.

Underestimation of the incidence of new-onset post-coronary artery bypass grafting atrial fibrillation and its impact on 30-day mortality

OBJECTIVE

Inconsistent definitions of atrial fibrillation after coronary artery bypass grafting have caused uncertainty about its incidence and risk. We examined the extent to which limiting the definition to post-coronary artery bypass grafting atrial fibrillation events requiring treatment underestimates its incidence and impact on 30-day mortality.

METHODS

We assessed in-hospital atrial fibrillation and 30-day mortality in 9268 consecutive patients without preoperative atrial fibrillation who underwent isolated coronary artery bypass grafting at 5 US hospitals (2004-2010). Patients who experienced 1 or more episode of post-coronary artery bypass grafting atrial fibrillation detected via continuous in-hospital electrocardiogram/telemetry monitoring were divided into those for whom Society of Thoracic Surgeons data (applying the definition "atrial fibrillation/flutter requiring treatment") also indicated atrial fibrillation versus those for whom it did not. Risk-adjusted 30-day mortality was compared between these 2 groups and with patients without post-coronary artery bypass grafting atrial fibrillation.

RESULTS

Risk-adjusted incidence of post-coronary artery bypass grafting atrial fibrillation incidence was 33.4% (27.0% recorded in Society of Thoracic Surgeons data, 6.4% missed). Patients with post-coronary artery bypass grafting atrial fibrillation missed by Society of Thoracic Surgeons data had a significantly greater risk of 30-day mortality (odds ratio, 2.08, 95% confidence interval, 1.17-3.69) than those captured. By applying the significant underestimation of post-coronary artery bypass grafting atrial fibrillation incidence we observed (odds ratio [Society of Thoracic Surgeons vs missed], 0.78; 95% confidence interval, 0.72-0.83) to the approximately 150,000 patients undergoing isolated coronary artery bypass grafting in the United States each year estimates this increased risk of mortality is carried by 9600 patients (95% confidence interval, 9420-9780) annually.

CONCLUSIONS

Defining post-coronary artery bypass grafting atrial fibrillation as episodes requiring treatment significantly underestimates incidence and misses patients at a significantly increased risk for mortality. Further research is needed to determine whether this increased risk carries over into long-term outcomes and whether it is mediated by differences in treatment and management.

Hospital Readmission and Length of Stay Over Time in Patients Undergoing Major Cardiovascular and Orthopedic Surgery: A Tale of 2 States

BACKGROUND

Readmission and length of stay (LOS) are increasingly accepted as quality measures for surgical care. Centers for Medicare & Medicaid Services will soon assess penalties for excessive readmissions after coronary artery bypass graft (CABG) surgery and hip and knee replacements.

OBJECTIVE

To determine and compare population level changes in LOS and relationship with 30-day readmission over time for patients undergoing CABG and hip and knee replacements. Secondary objective was to determine relationship between LOS and discharge disposition as well as mortality.

RESEARCH DESIGN

Observational cohort study of patients undergoing CABG and hip and knee replacements in New York and California. Temporal trends in LOS, discharge disposition, 30-day readmission, and mortality were examined. Generalized linear-mixed models, accounting for hospital clustering, were used to assess differences in outcomes.

SUBJECTS

Patients undergoing CABG and hip and knee replacements in New York and California between 2005 and 2011.

MEASURES

Trends in LOS, discharge disposition, 30-day readmission and mortality, and risk-adjusted odds of all-cause 30-day readmission.

RESULTS

We identified 206,784, 336,271, and 416,391 patients who underwent CABG, hip, and knee replacements, respectively, in New York State and California between 2005 and 2011. The risks of readmission within 30 days decreased over time in both states. LOS decreased by 1 day after hip and knee surgery and remained unchanged after CABG. Adjusted analysis confirmed these trends. In secondary analyses patients in New York had higher overall odds of 30-day readmission compared with patients in California.

CONCLUSIONS

We found no evidence of inverse relationship between LOS and readmission over time. In hip and knee replacement there is strong evidence that both LOS and readmission have been reduced simultaneously.

Coronary Perfusion Pressure during Antegrade Cardioplegia in On-Pump CABG Patients

OBJECTIVE:

The aim of this study was to investigate whether aortic tension estimated by palpation and cardioplegia infusion line pressure provide results equivalent to those obtained with direct aortic intraluminal pressure measurement.

METHODS:

Sixty consecutive patients who underwent coronary artery bypass graft surgeries with extracorporeal circulation were analyzed. Sanguineous cardioplegic solution in a ratio of 4:1 was administered using a triple lumen antegrade cannula. After crossclamping, cardioplegia was infused and aortic root pressure was recorded by surgeon (A) considering the aortic tension he felt in his fingertips. At the same time, another surgeon (B) recorded his results for the same measurement. Concomitantly, the anesthesiologist recorded intraluminal pressure in the aortic root and the perfusionist recorded delta pressure in cardioplegia infusion line. None of the participants involved in these measurements was allowed to be informed about the values provided by the other examiners.

RESULTS:

The Bland-Altman test showed that a considerable variation between aortic wall tension was found as measured by palpation and by intraluminal pressure, with a bias of -9.911±18.75% (95% limits of agreement: -46.7 to 26.9). No strong correlation was observed between intraluminal pressure and cardioplegia line pressure (Spearman's r=0.61, 95% confidence interval 0.5-0.7; P<0.0001).

CONCLUSION:

These findings reinforce that cardioplegia infusion should be controlled by measuring intraluminal pressure, and that palpation and cardioplegia line pressure are inaccurate methods, the latter should always be used to complement intraluminal measurement to ensure greater safety in handling the cardioplegia circuit.

The no-touch saphenous vein graft in elderly coronary bypass patients with multiple comorbidities is a promising conduit to substitute the left internal thoracic artery

OBJECTIVES

We investigated the patency rates of no-touch saphenous vein grafts anastomosed to the left anterior descending artery compared with the left internal thoracic artery. Further, we compared the patency of no-touch vein grafts to the left anterior descending artery with the patency of no-touch vein grafts to other coronary arteries.

METHODS

Of 2635 consecutive patients undergoing coronary artery bypass grafting between 2003 and 2008, 168 (6.3%) were given at least a saphenous vein graft to the left anterior descending artery to avoid harvesting complications in high-risk patients or in response to a left internal thoracic artery injury. A total of 97 patients were consecutively included after informed consent. A clinical examination and computed tomography angiography were performed on 91 patients at a mean of 6 (4-9) years.

RESULTS

The mean age of patients was 75.6 ± 8.5 years. Postoperatively, 88.7% of patients (86/97) were free of angina. The 91 examined patients had 163 grafts with 286 distal anastomoses. Crude patency, according to distal anastomoses, was 94.4% (270/286). The patency of single versus sequential no-touch vein grafts to the left anterior descending artery was 98% (50/51) versus 92.5% (37/40). The total patency rate was 95.6% (87/91), similar to the reported patency rate for the left internal thoracic artery. The no-touch grafts to the left anterior descending artery versus other coronaries had a patency of 95.6% (87/91) versus 93.8% (183/195), a high similarity confirmed by an equivalence analysis.

CONCLUSIONS

In elderly coronary bypass patients with multiple comorbidities, a no-touch saphenous vein graft is a promising substitute for the left internal thoracic artery.

Bilateral internal thoracic artery grafting in India-Time to raise the bar

Objectives

Bilateral internal thoracic artery (BITA) grafting strategy is the current trend in coronary artery bypass grafting for multivessel coronary artery disease. Although better long-term outcomes have been shown, BITA grafting is underutilized as a main strategy for revascularization by most of the surgeons. The survey was conducted to ascertain the current usage and concerns of BITA grafting in India.

Methods

Database of 856 Indian cardiac surgeons currently with predominantly adult practice was prepared and a questionnaire was sent about use of single and bilateral ITA grafts and BITA grafting strategy in different clinical scenarios.

Results

A total of 112 surgeons (13.08%) from 75 institutions responded and 92 surgeons (10.7%) completed the survey. Single ITA is used by 79% of surgeons in more than 90% of their patients. 31% and 29% of surgeons use BITA grafting in 5–10% and 11–98% of their patients respectively. 53% of surgeons avoided the usage of BITA grafting in patients with smoking, 35% of surgeons in chronic obstructive pulmonary disease, 58% of surgeons in obesity and 62% of surgeons in acute coronary syndrome, 36% of surgeons in patients with left ventricular dysfunction and 61% of surgeons in patients with poor coronary anatomy. The concerns for BITA usage are risk of deep sternal wound infection (DSWI) (40%), increased operative time (27%), unknown superiority (12%) and limited length of right ITA (5%).

Conclusions

The usage of BITA grafting is restricted to 10% in India and main concerns are DSWI and increased operative time.

Trends in Coronary Revascularization and Ischemic Heart Disease-Related Mortality in Israel

BACKGROUND

We investigated national trends in volume and outcomes of percutaneous coronary angioplasty (PCI), coronary artery bypass grafting (CABG), and ischemic heart disease-related mortality in Israel.

METHODS AND RESULTS

Using International Classification of Diseases 9th and 10th revision codes, we linked 5 Israeli national databases, including the Israel Center for Disease Control National PCI and CABG Registries, the Ministry of Health Hospitalization Report, the Center of Bureau of Statistics, and the Ministry of Interior Mortality Report, to assess the annual PCI and CABG volume, procedural mortality, comorbidities, and ischemic heart disease-related mortality between 2002 and 2014. Trends over time were analyzed using linear regression, assuming a Poisson distribution. A total of 298 390 revascularization procedures (PCI: 255 724, CABG: 42 666) were performed during the study period. PCI volume increased by 9% from 2002 to 2008 (387.4/100 000 to 423.2/100 000), steadily decreasing by 10.5% to 378.5/100 000 in 2014 (P=0.70 for the trend). CABG volume decreased by 59% (109.0/100 000 to 45.2/100 000) from 2002 to 2013, leveling at 46.4/100 000 (P<0.0001). PCI/CABG ratio increased from 3.6 in 2002 to 8.5 in 2013, slightly decreasing to 8.2 by 2014 (P<0.0001). In-hospital procedural mortality remained stable (PCI: 1.2-1.6%, P=0.34, CABG: 3.7-4.4%, P=0.29) despite a significant change in patient clinical profile. During the course of the study, ischemic heart disease-related mortality decreased by 46% (84.6-46/100 000, P<0.001).

CONCLUSIONS

We observed a dramatic change in coronary revascularization procedures type and volume, and a marked decrease in ischemic heart disease-related mortality in Israel. The reasons for the observed changes remain unclear and need to be further investigated.

Conduits Used in Coronary Artery Bypass Grafting: A Review of Morphological Studies

There is a significant variety of vascular conduits options for coronary bypass surgery. Adequate graft selection is the most important factor for the success of the intervention. To ensure durability, permeability, and bypass function, there must be a morphological similarity between the graft and the coronary artery. The objective of this review was to analyze the morphological characteristics of the grafts that are most commonly used in coronary bypass surgery and the coronary arteries that are most frequently occluded. We included clinical information regarding the characteristics that determine the behavior of the grafts and its permeability over time. Currently, the internal thoracic artery is the standard choice for bypass surgery because of the morphological characteristics of the wall that makes less prone to developing atherosclerosis and hyperplasia. The radial and right gastroepiploic arteries are the following second and third best options, respectively. The ulnar artery is the preferred choice when other conduits are not feasible.

Late results of the Cox-maze IV procedure in patients undergoing coronary artery bypass grafting

OBJECTIVE

Most patients with atrial fibrillation (AF) undergoing cardiac surgery do not receive concomitant ablation. This study reviewed outcomes of patients with AF undergoing Cox-maze IV (CMIV) procedure with radiofrequency and cryoablation and coronary artery bypass grafting (CABG) at our institution.

METHODS

Between the introduction of radiofrequency ablation in 2002 and 2015, 135 patients underwent left- or biatrial CMIV with CABG. Patients undergoing other cardiac procedures, except mitral valve repair, or who had emergent, reoperative, or off-pump procedures were excluded. Eighty-three patients remained in the study group after exclusion criteria were applied. Freedom from atrial tachyarrhythmias (ATAs) was ascertained using electrocardiogram, Holter monitor, or pacemaker interrogation at 1 to 5 years postoperatively.

RESULTS

Operative mortality was 3%. Freedom from ATAs at 1 year in the CMIV group was 98%, with 88% off antiarrhythmia drugs. Freedom from ATAs and antiarrhythmia drugs was 70% at 5 years.

CONCLUSIONS

The addition of CMIV to CABG resulted in excellent freedom from ATAs at 1 to 5 years. These patients are at increased risk for nonfatal complications compared with others undergoing concomitant surgical ablation.

The future of off-pump coronary artery bypass grafting: a North American perspective

Off-pump coronary artery bypass graft (OPCAB) is currently performed routinely in a minority of specialized centers and in many more centers, utilized only when a porcelain aorta mandates a no-touch aortic technique. The OPCAB literature can be summarized as follows: (I) large-scale randomized trials in relatively low risk patients that include surgeons with a range of experience demonstrating no consistent beneficial differences in major cardiovascular and cerebrovascular outcomes but lower transfusion rates and shorter length of stay, tempered by some reports of higher rates of incomplete revascularization and lower rates of long term graft patency; (II) smaller randomized controlled trials (RCTs) from highly specialized programs demonstrating equivalent or superior outcomes with OPCAB and similar completeness of revascularization and graft patency; and (III) observational data from large databases demonstrating a consistent benefit of OPCAB, especially in higher-risk patient subsets. Our rationale for OPCAB remains that if complete and precise revascularization can be safely and routinely accomplished, then the patient should benefit by avoiding the morbidities that can be attributed to aortic cannulation/clamping, cardiopulmonary bypass (CPB), hemodilution, hypothermia and global myocardial ischemia/cardioplegia. We further believe that OPCAB procedures should emphasize the use of arterial grafts to optimize long term patency and minimize aortic manipulation to limit the risk of stroke. Moving forward, the off-pump surgical community and specialty societies must address the challenge of training surgeons and their teams to master this technically demanding procedure. Furthermore, OPCAB opens the door to minimally-invasive surgical revascularization via hybrid coronary revascularization (HCR). A large NIH-funded RCT is currently underway to determine whether hybrid revascularization can offer a superior alternative to multi-vessel percutaneous coronary intervention for patients with low SYNTAX score and proximal LAD disease.

Sex Differences in the Epidemiology of New-Onset In-Hospital Post-Coronary Artery Bypass Graft Surgery Atrial Fibrillation: A Large Multicenter Study

BACKGROUND

New-onset atrial fibrillation (AF) after coronary artery bypass graft surgery (CABG) is associated with increased morbidity and poorer long-term survival. Although many studies show differences in outcome in women versus men after CABG, little is known about the sex-specific incidence and characteristics of post-CABG AF.

METHODS AND RESULTS

Overall, 11 236 consecutive patients without preoperative AF underwent isolated CABG from 2002 to 2010 at 4 US academic medical centers and 1 high-volume specialty cardiac hospital. Data routinely collected for the Society of Thoracic Surgeons database were augmented with details on new-onset post-CABG AF events detected via continuous in-hospital ECG/telemetry monitoring. Unadjusted incidence of post-CABG AF was 29.5% (3312/11 236) overall, 30.2% (2485/8214) in men, and 27.4% (827/3022) in women. After adjustment for Society of Thoracic Surgeons-recognized risk factors, women had significantly lower risk for post-CABG AF (odds ratio [95% confidence interval]=0.75 [0.64-0.89]), shorter first, longest, and total duration of AF episodes (mean difference [95% confidence interval]=-2.7 [-4.7 to -0.8] hours; -4.1 [-6.9 to -1.2] hours; -2.4 [-2.5 to -2.3] hours, respectively). At 48 hours, AF-free probabilities were 77% for women and 72% for men (P<0.001). Number of episodes (P=0.18), operative mortality (P=0.048), stroke (P=0.126), and discharge in AF (P=0.234) did not differ significantly by sex.

CONCLUSIONS

These novel data on sex-specific characteristics of new-onset AF after isolated CABG show that women had lower adjusted risk for post-CABG AF and experienced shorter episodes. Investigation of sex-specific impacts on outcomes is needed to identify optimal strategies for prevention and management to ensure all patients achieve the best possible outcomes.

Trends in isolated coronary artery bypass grafting over the last decade

OBJECTIVES

The purpose of this study was to assess the impact on hospital mortality and morbidity of extensive myocardial revascularization, using arterial grafts in patients undergoing isolated coronary artery bypass grafting (CABG).

METHODS

Our prospective perioperative database was used to define two groups of patients who underwent isolated CABG with cardiopulmonary bypass, based on the years in which the operation was performed: Group A (2000-2003; 898 patients) and Group B (2009-2012; 1249 patients). The baseline and operative characteristics and outcomes were compared.

RESULTS

Several significant changes in perioperative variables were observed. Group B included higher percentages of patients aged over 80 years (+58.1%), with diabetes (+32.0%) and with a history of percutaneous coronary intervention (+24.9%). The mean EuroSCORE II was significantly increased from 2.5 ± 4.4% in Group A to 3.2 ± 5.7% in Group B (P= 0.001). The mean number of distal anastomoses was significantly increased over time (total: 2.6 ± 0.8 vs 3.1 ± 1.0, P< 0.0001 and with arterial grafts: 1.6 ± 0.8 vs 2.6 ± 0.9, P< 0.0001). In-hospital mortality was low and did not significantly differ between Groups A and B (1.3 vs 2.4%; P= 0.08). Significant increases of new-onset atrial fibrillation (11.7 vs 21.9%, P= 0.017) and deep sternal infection (0.2 vs 1.1%, P= 0.017) were observed in Group B, compared with Group A. In multivariate analysis, extensive use of arterial grafts was not a risk factor of hospital mortality or sternal morbidity.

CONCLUSIONS

Despite the increasing risk profiles of patients undergoing CABG, extensive myocardial revascularization using arterial grafts is associated with good early results.

Muscle strength differ between patients with diabetes and controls following heart surgery

BACKGROUND

The aim of our study was to analyze muscle strength in patients with recent surgical treatment for ischemic and combined ischemic-valvular heart disease, based on existence of diabetes mellitus. Connections existing between muscle strength and patient characteristics or conventional diagnostic tests were analyzed as well.

METHODS

Study prospectively included consecutive patients scheduled for cardiovascular rehabilitation 0-3months after heart surgery. Diagnostics covered drug utilization, anthropometrics, demographics, echocardiography, conventional laboratory, echocardiography, bioelectrical impedance analysis (BIA), and hand grip test (HGT). HGT was analyzed for dominant hand.

RESULTS

Patients with diabetes had significantly weaker muscle strength on HGT than controls; 29.4±12.2kg vs. 38.2±14.7kg (p=0.029), respectively. ROC analysis for HGT and existence of diabetes mellitus were significant; ≤40kg had sensitivity of 89.7% (95%CI: 72.6-97.8), specificity 43.7% (31.9-56.0); AUC 0.669 (0.568-0.760); p=0.002. HGT significantly correlated with hematocrit (Rho CC=0.247; p=0.013), whilst other laboratory or echocardiographic parameters were insignificant (all p>0.05). HGT also correlated with body weight (Rho CC=0.510; p<0.001); height (Rho CC=0.632; p<0.001); waist circumference (Rho CC=0.388; p<0.001); waist-to-hip ratio (Rho CC=0.274; p=0.006) and BIA (Rho CC=-0.412; p<0.001).

CONCLUSIONS

In postoperative recovery of patients with diabetes, muscle strength assessed by HGT is decreased and in relation with nutritional status. Clinically resourceful connections of HGT were also found to hematocrit and utilization of loop diuretics.

Does Previous Transradial Catheterization Preclude Use of the Radial Artery as a Conduit in Coronary Artery Bypass Surgery?

The radial artery (RA) is a commonly used conduit for coronary artery bypass grafting, and recent studies have demonstrated that it provides superior long-term patency rates to the saphenous vein in most situations. In addition, the RA is also being used with increasing frequency as the access point for coronary angiography and percutaneous coronary interventions. However, there has been concern for many years that these transradial procedures may have a detrimental impact on the function of RA grafts used in coronary artery bypass grafting, and there is now comprehensive evidence that such interventions cause morphologic and functional damage to the artery in situ. Despite this, there remain remarkably few studies investigating the use of previously cannulated RAs as grafts in coronary artery bypass surgery, and there are no clear guidelines on the use of the RA in coronary artery bypass grafting after its catheterization. This article will review concisely the evidence that transradial procedures cause damage to the RA, and discuss the impact this could have on previously cannulated RAs used as coronary artery bypass grafting conduits. On the basis of the evidence assessed, we make a number of recommendations to both surgeons and cardiologists regarding use of the RA in cardiovascular procedures.