ACC/AHA 2004 Guideline Update for Coronary Artery Bypass Graft Surgery: Summary Article

Staged Versus Concomitant Carotid Endarterectomy and Aortic Valve Replacement: A Case Report and Literature Review

Stroke is a common complication of cardiac surgery, and carotid artery stenosis is an established risk factor for stroke. Therefore, patients with carotid artery stenosis who are undergoing cardiac surgery require proper management of the former either simultaneously or before cardiac surgery. We present a challenging case of a 67-year-old male patient who presented with generalized weakness, severe aortic stenosis, and significant bilateral carotid artery stenosis. The coexistence of these findings sparked a debate about whether to perform a carotid endarterectomy first or an aortic valve replacement. Moreover, a past history of percutaneous coronary intervention and coronary artery bypass grafts made the decision more challenging. Multiple approaches have been employed for the management of coexisting carotid artery stenosis with cardiac surgery; however, no definitive guidelines exist, especially for surgeries other than coronary artery bypass grafts or where the carotid stenosis is bilateral and severe.

Associations of ApoE Polymorphisms with Postoperative Atrial Fibrillation and Cardiac Injury in Patients with Coronary Artery Bypass Graft Surgery

Genetic factors may be involved in postoperative atrial fibrillation (PoAF) development and cardiac injury. However, the associations of the apolipoprotein E (ApoE) gene polymorphisms with PoAF and cardiac injury after coronary artery bypass graft surgery (CABG) remain unclear.We recruited 150 patients with CABG, comprising 92 and 58 cases for the ApoE4 and ApoE3 groups, respectively, and analyzed PoAF incidence and the levels of cardiac biomarkers, including N-terminal prohormone of brain natriuretic peptide, cardiac troponin T (cTnT), and cardiac troponin I (cTnI). The linear regression model or logistic regression analysis was applied to investigate the associations of ApoE gene polymorphisms with PoAF and biomarkers for cardiac injury.A total of 58 (38.7%) patients with CABG developed PoAF, with 40 and 18 cases in the ApoE4 and ApoE3 groups (43.5% versus 31.0%, P < 0.05), respectively. Logistic regression analysis revealed that the ApoE4 allele was an independent risk factor for PoAF (OR = 3.340, P = 0.001), while the ApoE3 allele was a protective factor for the PoAF (OR = 0.841, P = 0.043). Patients carrying the ApoE4 allele had higher levels of cTnT and cTnI than those carrying the ApoE3 allele. ApoE3 was a protective factor for cardiac injury (β = -0.220, P = 0.001), whereas ApoE4 was a risk factor for cTnI (β = 0.335, P = 0.015).Our study reveals that the ApoE allele contributes to the occurrence of PoAF and severity of cardiac injury in an allele-dependent manner, with the ApoE4 allele increasing the risk and the ApoE3 allele reducing the risk.

The Role of Systemic Immune Inflammation Index for Predicting Saphenous Vein Graft Disease in Patients with Coronary Artery Bypass Grafting

As inflammation plays a significant role in the development of coronary artery disease, we hypothesized that there may be a relation between the systemic immune inflammation index (SII) and saphenous vein graft disease (SVGD). The study population consisted of 716 consecutive patients who underwent elective coronary angiography (CAG) >1 year after bypass grafting. The patients were divided into 2 groups depending on the extent of SVG patency. SII value was significantly higher in the SVGD(+) group compared with the SVGD(-) group (P < .001). In multivariate logistic regression analysis, SII (P < .001, odds ratio (OR) = 3.27, 95% CI = 1.94-5.65) and neutrophil-to-lymphocyte ratio (NLR) (P < .001, OR = 2.08, 95% CI = 1.59-3.11) were found to be independent predictors of SVGD. An SII value of >935 (x10³/ml) has 89.2% sensitivity and 70.6% specificity for the prediction of the SVGD, and an NLR value of >4.15 has 54.6% sensitivity and 68.5% specificity for the prediction of the SVGD. The AUC of SII was found to be greater than the AUC of NLR (P = .002), platelet-to-lymphocyte ratio (PLR) (P = .009), lymphocyte-to-monocyte ratio (LMR) (P = .013), MPV (P = .011), and C-reactive protein (CRP) (P = .034) in predicting SVGD. In conclusion, we demonstrated that SII, which is among the new inflammation indexes, is a more reliable predictor in determining SVGD than the NLR, PLR, and LMR.

Impaired fibrin clot lysis is associated with increased mortality in patients after coronary artery bypass grafting: A long-term follow-up study

BACKGROUND

Mortality after coronary artery bypass grafting (CABG) is primarily thromboembolic by nature. We investigated whether impaired fibrinolysis observed in cardiovascular diseases is associated with long-term mortality following CABG.

METHODS

The study population comprised 292 consecutive patients (aged 64.6 ± 8.1 years) who underwent scheduled CABG. We measured plasma clot lysis time (CLT) preoperatively as a measure of fibrinolysis capacity. Cardiovascular and all-cause deaths were recorded during a median follow-up of 13.8 years.

RESULT

CLT positively correlated with age (r = .56, p < .001), fibrinogen (r = .25, p = .002) and EuroSCORE I (r = .32, p < .001). The cardiovascular and overall mortality rates were 3.0 and 4.9 per 100 patient-years (32.4% vs 52.8%) respectively. In patients who died from cardiovascular and all causes, CLT was prolonged compared with survivors (both p < .050). Multivariable Cox regression analysis adjusted for potential confounders showed that long-term cardiovascular and all-cause deaths were associated with CLT (HR per 10 min 1.206; 95% CI 1.037-1.402, p = .015 and HR 1.164; 96% CI 1.032-1.309, p = .012), low-density lipoprotein cholesterol (HR per 1 mmol/L 1.556; 95% CI 1.205-2.010, p < .001 and HR 1.388; 96% CI 1.125-1.703, p = .002), C-reactive protein (HR per 10 mg/L 1.171; 95% CI 1.046-1.312, p = .006 and HR 1.127; 95% CI 1.005-1.237, p = .022) and EuroSCORE I (HR 1.173; 95% CI 1.016-1.355, p = .030 and HR 1.183; 95% CI 1.059-1.317, p = .003 respectively). Type 2 diabetes was solely associated with overall mortality (HR 1.594; 96% CI 1.088-2.334, p = .017).

CONCLUSIONS

In this study, we showed that reduced fibrin clot susceptibility to fibrinolysis is weekly associated with long-term mortality in advanced CAD.

Serum FGF21 Levels Predict the MACE in Patients With Myocardial Infarction After Coronary Artery Bypass Graft Surgery

Objectives

Prognosis evaluation in myocardial infarction (MI) patients with major adverse clinical events (MACE) who have undergone coronary artery bypass graft (CABG) is greatly important to identify high-risk patients. Elevated metabolic hormone fibroblast growth factor 21 (FGF21) is associated with the risk of MI. The aim of this study is to assess the relationship between FGF21 and the incidence of MACE in patients with MI after CABG surgery.

Methods

Patients with three-vessel disease who were scheduled for first-time isolated CABG were enrolled in this project and underwent to evaluate the incidence of MACE during 48 h after CABG surgery, as well as to collect serum samples for FGF21 levels in both preoperative- and postoperative-CABG (pre-CABG and post-CABG).

Results

A total of 265 patients with MI undergoing CABG were enrolled in this study, 21 patients experienced MACE during the 48 h after CAGB surgery. Serum FGF21 levels of patients with MACE at post-CABG were significantly higher than that in patients without MACE [553.7 (433.6) vs. 291.7 (334.4), p &lt; 0.001]. Furthermore, among 81 individuals of these 265 patients, a lower level of FGF21 in preoperative-CABG (pre-CABG) and a higher level of FGF21 at postoperative-CABG (post-CABG) were observed in MI patients with MACE as compared to those without MACE respectively [ (275.0 (260.4) vs. 410.3 (420.7), p = 0.049; 550.7 (519.9) vs. 370.6 (441.2), p = 0.031]. In addition, serum FGF21 levels of MI patients with MACE at post-CABG were significantly increased compared with the baseline levels in pre-CABG [550.7 (519.9) vs.275.0 (260.4) p &lt; 0.001]. However, these profiles were not observed in patients without MACE [410.3 (420.7) vs. 370.6 (441.2), p=0.2137]. Logistic regression analysis demonstrated that both serum FGF21 and CK-MB levels at post-CABG were independently associated with the incidence of MACE in patients with MI after CABG surgery. Finally, ROC analysis for FGF21 levels of 265 MI patients at post-CABG identified 455.4 pg/ml as an optimal cut-off value to predict MACE, with a sensitivity and specificity of 91.7 and 68.4% respectively.

Conclusion

Serum FGF21 levels at post-CABG are independently associated with the incidence of MACE in patients with MI who have undergone CABG. Measurement of FGF21 may help distinguish patients with MI at a high risk of MACE after CABG surgery.

8-Isoprostanes and Asymmetric Dimethylarginine as Predictors of Mortality in Patients Following Coronary Bypass Surgery: A Long-Term Follow-Up Study

BACKGROUND

We previously demonstrated that enhanced oxidative stress and reduced nitric oxide bioavailability are associated with unfavorable outcomes early after coronary artery bypass grafting. It is not known whether these processes may impact long-term results. We sought to assess whether during long-term follow-up, markers of oxidative stress and nitric oxide bioavailability may predict cardiovascular mortality following bypass surgery.

METHODS

We studied 152 consecutive patients (118 men, age 65.2 ± 8.3 years) who underwent elective, primary, isolated on-pump bypass surgery. We measured plasma 8-iso-prostaglandin F2α and asymmetric dimethylarginine before surgery and twice after surgery (18-36 h and 5-7 days). We assessed all-cause and cardiovascular death in relation to these two biomarkers during a mean follow-up time of 11.7 years.

RESULTS

The overall mortality was 44.7% (4.7 per 100 patient-years) and cardiovascular mortality was 21.0% (2.2 per 100 patient-years). Baseline 8-iso-prostaglandin F2α was associated with cardiovascular mortality (HR 1 pg/mL 1.010, 95% CI 1.001-1.021, p = 0.036) with the optimal cut-off ≤ 364 pg/mL for higher survival rate (HR 0.460, 95% CI 0.224-0.942, p = 0.030). Asymmetric dimethylarginine > 1.01 μmol/L measured 18-36 h after surgery also predicted cardiovascular death (HR 2.467, 95% CI 1.140-5.340, p = 0.020). Additionally, elevated 8-iso-prostaglandin F2α measured at the same time point associated with all-cause mortality (HR 1 pg/mL 1.007, 95% CI 1.000-1.014, p = 0.048).

CONCLUSIONS

Our findings indicate that in advanced coronary disease, increased oxidative stress, reflected by 8-iso-prostaglandin F2α before bypass surgery and enhanced asymmetric dimethylarginine accumulation just after the surgery are associated with cardiovascular death during long-term follow-up.

Mini-extracorporeal circulation surgery produces less inflammation than off-pump coronary surgery

OBJECTIVES

Both off-pump coronary artery bypass grafting surgery (OPCABG) and mini-extracorporeal circulation (MECC) have been associated with lower morbidity and mortality and less inflammation than conventional cardiopulmonary bypass. However, studies comparing the 2 techniques are scarce and the results are controversial. We compared the clinical outcomes and inflammatory response of low-risk patients undergoing coronary bypass grafting with MECC versus OPCABG.

METHODS

We conducted a prospective, randomized study in patients undergoing coronary heart surgery. Two hundred and thirty consecutive low-risk patients were randomly assigned to either receive OPCABG (n = 117) or MECC (n = 113). Clinical outcomes and postoperative biochemical results were analysed in both groups. We also analysed 19 circulating inflammatory markers in a subgroup of 40 patients at 4 perioperative time points. The area under the curve for each marker was calculated to monitor differences in the inflammatory response.

RESULTS

No significant differences were found between groups regarding perioperative clinical complications and no deaths occurred during the trial. Plasma levels in 9 of the 19 inflammatory markers were undetectable or showed no temporal variation, 3 were higher in the MECC group [interleukin (IL)-10, macrophage inflammatory protein-1β and epidermal growth factor] and 7 were higher in the OPCABG group (growth regulator oncogene, IL-6, IL-8, soluble CD40 ligand, monocyte chemoattractant protein-1, monocyte chemoattractant protein-3 and tumour necrosis factor-α). Differences in 2 proinflammatory cytokines, IL-6 and monocyte chemoattractant protein 1, between the 2 surgical procedures were statistically significant.

CONCLUSIONS

No clinical differences were observed between in low-risk patients undergoing MECC or OPCABG surgery, but OPCABG was associated with an increased release of proinflammatory cytokines compared with MECC. Studies in larger cohorts and in patients at higher risk are needed to confirm these findings.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02118025.

Platelet transfusion for patients with platelet dysfunction: effectiveness, mechanisms, and unanswered questions

PURPOSE OF REVIEW

In this review, we discuss current clinical guidelines and potential underlying mechanisms regarding platelet transfusion therapy in patients at risk of bleeding, comparing management of patients with thrombocytopenia versus those with qualitative platelet disorders.

RECENT FINDINGS

Platelet transfusion therapy is highly effective in managing bleeding in patients with hypoproliferative thrombocytopenia. Clinical trials have demonstrated that platelet transfusion can be used at a lower trigger threshold and reduced platelet doses, and may be used therapeutically rather than prophylactically in some situations, although additional data are needed. In patients with inherited platelet disorders such as Glanzmann's Thrombasthenia or those with RASGRP2 mutations, platelet transfusion may be ineffective because of competition between transfused and endogenous platelets at the site of vascular injury. Successful management of these patients may require transfusion of additional platelet units, or mechanism-driven combination therapy with other pro-hemostatic agents. In patients on antiplatelet therapy, timing of transfusion and inhibitor mechanism-of-action are key in determining therapeutic success.

SUMMARY

Expanding our understanding of the mechanisms by which transfused platelets exert their pro-hemostatic function in various bleeding disorders will improve the appropriate use of platelet transfusion.

Impact of lipid levels and high-intensity statins on vein graft patency after CABG: Midterm results of the ACTIVE trial

BACKGROUND

High-dose atorvastatin did not improve 1-year vein graft patency in the recent Aggressive Cholesterol Therapy to Inhibit Vein Graft Events trial. However, it remains unknown whether high-intensity statins may impact graft disease in the years that follow.

METHODS

In the trial, patients (N = 173) were randomized to receive atorvastatin 10 or 80 mg for 1 year after coronary bypass surgery (CABG). Beyond 1 year, the choice of statin was left to the patient's physician. In this study of participants who agreed to follow-up (N = 76), low-density lipoprotein (LDL) levels were measured and graft patency was assessed 3 years after surgery.

RESULTS

The rate of vein graft disease 3 years after surgery was not significantly reduced with atorvastatin 80 mg during the first postoperative year or the use of open-label high-intensity statin thereafter (p = NS). However, a trend was observed between higher LDL levels during the first postoperative year and a greater incidence of vein graft disease at 3 years (p = .12). Among patients who had LDL levels more than 90 mg/dl in the first year after CABG, 38.5% had vein graft disease at 3 years, compared to 19.0% for those with LDL levels less than 90 mg/dl (p = .15). Higher mean LDL levels during the first postoperative year were associated with a higher rate of vein disease 3 years after surgery both at the graft level (p = .03) and at the patient level (p = .03) in multivariate analysis.

CONCLUSIONS

Higher LDL levels during the first postoperative year were associated with significantly greater vein graft disease 3 years after CABG.

Effects of physical exercise on the autonomic nervous system in patients with coronary artery disease: a systematic review

BACKGROUND

Imbalance in autonomic modulation can occur after a cardiac event, which can lead to deleterious consequences. Exercise has proven to be a therapy which affects this modulation and can be assessed through heart rate variability (HRV).

AREAS COVERED

The objective of this systematic review was to investigate the effects of physical exercise on heart rate variability in individuals with coronary artery disease (CAD). The PubMed, PEDro, Scielo, Lilacs and Cochrane databases were systematically searched, for articles which performed supervised exercises in phase II of cardiac rehabilitation in patients with CAD.

EXPERT OPINION

Given the differences between studies on interventions and population characteristics, it is difficult to justify similarities or divergences in terms of results. In addition to the variation in sample size, intervention duration, carrying out an additional program at home, and patients with different clinical presentations, it can be inferred that responses to exercise may vary for certain types/clinical profile of individuals with CAD. Thus, it is necessary to carry out more studies with greater methodological rigor, greater standardization of the variables studied and the evaluation forms, in order to increase the veracity of the results and the consequent clinical relevance and therapeutic application.

Rapid Self-Assembly of Bioengineered Cardiovascular Bypass Grafts From Scaffold-Stabilized, Tubular Bilevel Cell Sheets

BACKGROUND

Cardiovascular bypass grafting is an essential treatment for complex cases of atherosclerotic disease. Because the availability of autologous arterial and venous conduits is patient-limited, self-assembled cell-only grafts have been developed to serve as functional conduits with off-the-shelf availability. The unacceptably long production time required to generate these conduits, however, currently limits their clinical utility. Here, we introduce a novel technique to significantly accelerate the production process of self-assembled engineered vascular conduits.

METHODS

Human aortic smooth muscle cells and skin fibroblasts were used to construct bilevel cell sheets. Cell sheets were wrapped around a 22.5-gauge Angiocath needle to form tubular vessel constructs. A thin, flexible membrane of clinically approved biodegradable tissue glue (Dermabond Advanced) served as a temporary, external scaffold, allowing immediate perfusion and endothelialization of the vessel construct in a bioreactor. Subsequently, the matured vascular conduits were used as femoral artery interposition grafts in rats (n=20). Burst pressure, vasoreactivity, flow dynamics, perfusion, graft patency, and histological structure were assessed.

RESULTS

Compared with engineered vascular conduits formed without external stabilization, glue membrane-stabilized conduits reached maturity in the bioreactor in one-fifth the time. After only 2 weeks of perfusion, the matured conduits exhibited flow dynamics similar to that of control arteries, as well as physiological responses to vasoconstricting and vasodilating drugs. The matured conduits had burst pressures exceeding 500 mm Hg and had sufficient mechanical stability for surgical anastomoses. The patency rate of implanted conduits at 8 weeks was 100%, with flow rate and hind-limb perfusion similar to those of sham controls. Grafts explanted after 8 weeks showed a histological structure resembling that of typical arteries, including intima, media, adventitia, and internal and external elastic membrane layers.

CONCLUSIONS

Our technique reduces the production time of self-assembled, cell sheet-derived engineered vascular conduits to 2 weeks, thereby permitting their use as bypass grafts within the clinical time window for elective cardiovascular surgery. Furthermore, our method uses only clinically approved materials and can be adapted to various cell sources, simplifying the path toward future clinical translation.

Unplanned 30-Day Readmission after Coronary Artery Bypass in Patients with Acute Myocardial Infarction

BACKGROUND/PURPOSE

The Centers for Medicare and Medicaid services penalizes hospitals with higher than expected readmissions for coronary artery bypass graft surgery (CABG). Little information exists regarding outcomes in patients who sustain an acute myocardial infarction (MI) and undergo CABG as the primary revascularization strategy. Our goal was to determine the unplanned 30-day readmission rate in this high-risk population and predictors of readmission.

MATERIALS/METHODS

An institutional database was queried to identify patients from 2011 to 2017 who were admitted with an acute MI and underwent CABG within 30 days. Chart review was performed to collect demographics, medical comorbidities and clinical information related to hospital course and readmission status.

RESULTS

A total of 150 patients were included. The 30-day unplanned readmission rate was 23%, and the majority (80%) were non-cardiac related. Predictors of unplanned readmission included female sex (OR 2.61, 95% CI 1.042-6.549, p = 0.041), CABG performed <7 days following MI (OR 2.82, 95% CI 1.21-6.59, p = 0.017), and post-operative atrial fibrillation (OR 3.25, 95% CI 1.07-9.87, p = 0.038). Complications were identified in 32% of clinic visits in patients who did not require readmission.

CONCLUSIONS

Patients who undergo CABG following MI are a high-risk population with nearly one-quarter readmitted within 30 days. Female sex, <7 days between the index MI and CABG, and post-operative atrial fibrillation are strong predictors for readmission. Early outpatient follow-up may be an effective intervention to reduce hospital readmissions by reassuring patients that non-cardiac symptoms are in line with anticipated post-operative pain and healing.

Pre-cardiopulmonary bypass administration of dexmedetomidine decreases cardiac troponin I level following cardiac surgery with sevoflurane postconditioning

Objective

This study was performed to determine the effect of dexmedetomidine (DEX) administration on myocardial damage in cardiac surgery with sevoflurane postconditioning.

Methods

We retrospectively examined all cardiac valve replacement surgeries from 1 April 2016 to 30 April 2017. Eligible patients were divided into two groups based on whether DEX was infused. DEX infusion was permitted only between intubation and the beginning of cardiopulmonary bypass (CPB). Sevoflurane was inhaled via the standard postconditioning procedure starting at aortic declamping. The cardiac troponin I (cTnI) level was measured at different time points. The postoperative outcomes and complications were also analyzed.

Results

One hundred patients were included in the study (DEX group, n = 53; non-DEX group, n = 47). Increased cTnI levels were significantly correlated with the New York Heart Association classification, CPB time, and DEX use. DEX use and the CPB time were potential independent factors contributing to changes in the cTnI level. The cTnI level at 6, 12, and 24 hours postoperatively was remarkably lower in the DEX than non-DEX group by 1.14, 7.83, and 5.86 ng/mL, respectively.

Conclusions

DEX decreased the cTnI level after CPB when sevoflurane postconditioning was used, especially at 6, 12, and 24 hours postoperatively.

Elevated expression of the metalloproteinase ADAM8 associates with vascular diseases in mice and humans

BACKGROUND AND AIMS

Members of the family of a disintegrin and metalloproteinases (ADAMs) and their substrates have been previously shown to modulate the inflammatory response in cardiac diseases, but studies investigating the relevance of ADAM8 are still rare. Our aim is to provide evidence for the inflammatory dysregulation of ADAM8 in vascular diseases and its association with disease severity.

METHODS

Western-type diet fed Apoe^-/- and Ldlr^-/- mice and artery ligation served as murine model for atherosclerosis and myocardial infarction, respectively. Human bypass grafts were used to study the association with coronary artery disease (CAD), with the simplified acute physiology score II (SAPS II) as a measure of postoperative organ dysfunction. Human primary vascular and blood cells were analyzed under basal and inflammatory conditions. mRNA levels were determined by RT-qPCR, ADAM8 protein levels by ELISA, immunohistochemistry or flow cytometry.

RESULTS

ADAM8/ADAM8 expression is associated with atherosclerosis and CAD such as myocardial infarction in both mice and humans, especially in endothelial cells and leukocytes. We observed a strong in vivo and in vitro correlation of ADAM8 with the vascular disease markers VCAM-1, ICAM-1, TNF, IL-6, and CCL-2. Serum analysis revealed a significant elevation of soluble ADAM8 serum levels correlating with soluble CXCL16 levels and SAPS II.

CONCLUSIONS

We demonstrate a general association of ADAM8 with cardiovascular diseases in mice and humans predominantly acting in endothelial cells and leukocytes. The correlation with postoperative organ dysfunctions in CAD patients highlights the value of further studies investigating the specific function of ADAM8 in cardiovascular diseases.

Long-Term Outcome of Patients Undergoing Minimally Invasive Direct Coronary Artery Bypass Surgery: A Single-Center Experience

OBJECTIVE

The primary objective was to investigate the long-term survival of patients who underwent single-vessel coronary revascularization with minimally invasive direct coronary artery bypass surgery with or without hybrid revascularization. The secondary outcome measures were repeat revascularization either by coronary artery bypass grafting or by percutaneous coronary intervention and the incidence of myocardial infarction or recurrent angina.

METHODS

This is a retrospective study of prospectively collected data of patients who underwent minimally invasive direct coronary artery bypass procedure in our center between January 2001 and December 2015. Procedures were performed either through small left anterolateral thoracotomy or lower midline sternotomy.

RESULTS

A total of 182 patients were identified: 100 underwent minimally invasive direct coronary artery bypass to the left anterior descending artery and 82 underwent hybrid revascularization (percutaneous coronary intervention to coronary arteries other than the left anterior descending artery along with minimally invasive direct coronary artery bypass to the left anterior descending artery). The mean ± SD age was 62 ± 10.1 years. Preoperatively 82% were male, and 72.5% patients had good left ventricular function. The median follow-up period was 10.9 years. There was no in-hospital or 30-day mortality. The 10-year actuarial survival was 84.8%. Freedom from repeat revascularization was 98.9% at 1 year and 89.9% at 10 years. At follow-up, freedom from myocardial infarction was 96.7% whereas freedom from angina was 92.9%.

CONCLUSIONS

Within the limitations imposed by retrospective analyses, our study demonstrates excellent long-term outcome in patients undergoing minimally invasive direct coronary artery bypass with or without hybrid revascularization. For isolated left anterior descending artery disease minimally invasive direct coronary artery bypass should be considered, whereas hybrid revascularization (percutaneous coronary intervention and minimally invasive direct coronary artery bypass) should be considered for multivessel disease.

Contemporary Management of Patients with Concomitant Coronary and Carotid Artery Disease

The ideal management of concomitant carotid and coronary artery occlusive disease remains elusive. Although researchers have advocated the potential benefits of varying treatment strategies based on either concomitant or staged surgical treatment, there is no consensus in treatment guidelines among national or international clinical societies. Clinical studies show that coronary artery bypass grafting (CABG) with either staged or synchronous carotid endarterectomy (CEA) is associated with a high procedural stroke or death rate. Recent clinical studies have found carotid artery stenting (CAS) prior to CABG can lead to superior treatment outcomes in asymptomatic patients who are deemed high risk of CEA. With emerging data suggesting favorable outcome of CAS compared to CEA in patients with critical coronary artery disease, physicians must consider these diverging therapeutic options when treating patients with concurrent carotid and coronary disease. This review examines the available clinical data on therapeutic strategies in patients with concomitant carotid and coronary artery disease. A treatment paradigm for considering CAS or CEA as well as CABG and percutaneous coronary intervention is discussed.

Vitamin C to Improve Organ Dysfunction in Cardiac Surgery Patients-Review and Pragmatic Approach

The pleiotropic biochemical and antioxidant functions of vitamin C have sparked recent interest in its application in intensive care. Vitamin C protects important organ systems (cardiovascular, neurologic and renal systems) during inflammation and oxidative stress. It also influences coagulation and inflammation; its application might prevent organ damage. The current evidence of vitamin C's effect on pathophysiological reactions during various acute stress events (such as sepsis, shock, trauma, burn and ischemia-reperfusion injury) questions whether the application of vitamin C might be especially beneficial for cardiac surgery patients who are routinely exposed to ischemia/reperfusion and subsequent inflammation, systematically affecting different organ systems. This review covers current knowledge about the role of vitamin C in cardiac surgery patients with focus on its influence on organ dysfunctions. The relationships between vitamin C and clinical health outcomes are reviewed with special emphasis on its application in cardiac surgery. Additionally, this review pragmatically discusses evidence on the administration of vitamin C in every day clinical practice, tackling the issues of safety, monitoring, dosage, and appropriate application strategy.

Predictive Ability of Novel Cardiac Biomarkers ST2, Galectin-3, and NT-ProBNP Before Cardiac Surgery

BACKGROUND

Current preoperative models use clinical risk factors alone in estimating risk of in-hospital mortality following cardiac surgery. However, novel biomarkers now exist to potentially improve preoperative prediction models. An assessment of Galectin-3, N-terminal pro b-type natriuretic peptide (NT-ProBNP), and soluble ST2 to improve the predictive ability of an existing prediction model of in-hospital mortality may improve our capacity to risk-stratify patients before surgery.

METHODS AND RESULTS

We measured preoperative biomarkers in the NNECDSG (Northern New England Cardiovascular Disease Study Group), a prospective cohort of 1554 patients undergoing coronary artery bypass graft surgery. Exposures of interest were preoperative levels of galectin-3, NT-ProBNP, and ST2. In-hospital mortality and adverse events occurring after coronary artery bypass graft were the outcomes. After adjustment, NT-ProBNP and ST2 showed a statistically significant association with both their median and third tercile categories with NT-ProBNP odds ratios of 2.89 (95% confidence interval [CI]: 1.04-8.05) and 5.43 (95% CI: 1.21-24.44) and ST2 odds ratios of 3.96 (95% CI: 1.60-9.82) and 3.21 (95% CI: 1.17-8.80), respectively. The model receiver operating characteristic score of the base prediction model (0.80 [95% CI: 0.72-0.89]) varied significantly from the new multi-marker model (0.85 [95% CI: 0.79-0.91]). Compared with the Northern New England (NNE) model alone, the full prediction model with biomarkers NT-proBNP and ST2 shows significant improvement in model classification of in-hospital mortality.

CONCLUSIONS

This study demonstrates a significant improvement of preoperative prediction of in-hospital mortality in patients undergoing coronary artery bypass graft and suggests that biomarkers can be used to identify patients at higher risk.

Physiotherapy mobility and walking management of uncomplicated coronary artery bypass graft (CABG) surgery patients: a survey of clinicians' perspectives in Australia and New Zealand

Background: This study aimed to determine current mobility and walking management by physiotherapists of patients undergoing coronary artery bypass graft (CABG) surgery, the clinical milestones expected and physiotherapists' perception of the severity of pain experienced by patients after surgery. Design: Cross sectional study using a questionnaire. Methods: All hospitals in Australia and New Zealand that perform cardiac surgery (n = 54) were invited to complete a questionnaire. Findings: Forty-one questionnaires were returned and analysed (response rate 76%). Walking distance was a clinical milestone after CABG surgery. Walking and transferring patients from bed to chair required the most time of physiotherapists during one treatment session. Physiotherapists perceived that patients experienced most pain on day one after surgery [mean (SD)] visual analogue scale (VAS) 41 (16) mm and this reduced by day four to VAS 15 (10) mm. Patients' pain was perceived to be significantly higher after physiotherapy sessions compared with before (p < 0.01). Thirty-seven respondents (90%) believed that patients' pain was well managed for physiotherapy treatments. A majority of the respondents (68%) believed that pain was not a limiting factor in the distance patients walked in a physiotherapy session and most (90%) believed that general fatigue limited walk distance. Conclusion: This research provides current mobility and walking management by physiotherapists of patients undergoing CABG surgery in Australia and New Zealand.

Effect of physiotherapy on quality of life after coronary artery bypass graft surgery: A randomized study

Background:

This study aims to assess the impact that physiotherapy (PT) has on the quality of life (QoL) of patients who have undergone coronary artery bypass grafting (CABG) surgery. The objective of this study was to assess the effect of PT on physical and mental aspects of patients’ QoL.

Materials and Methods:

The study population consisted of 50 patients who aged between 60 and 70 years and who had previously undergone CABG surgery. The patients were randomly allocated to two groups: a PT group (n = 25) and a control group (n = 25). The physical characteristics of the participants were recorded at the outset of the study. The patients who were allocated to the PT group completed 16 sessions of classic PT. QoL assessments of all participants were performed before and after the program in the form of a short form-36 health survey. An independent sample t-test and an ANCOVA were performed for the purpose of statistical analyses.

Results:

The QoL scores of the patients (mean age = 62.08 years) who underwent PT significantly improved after the intervention (P < 0.001). A significant difference between groups was observed (P < 0.001) in both the mental component summary and physical component summary variables.

Conclusion:

PT can help relieve pain, reduce depression, help patients more effectively perform the tasks of everyday living, and help ease the symptoms of other disabilities associated with cardiac surgery. In the current study, the implementation of a PT program improved the patient's mental health and increased their QoL.

Incidence, predictors, clinical profile, management and outcome of patients with isolated left main coronary artery ostial disease

Objectives

Isolated left main coronary artery (LMCA) ostial disease is a rare variant of LMCA disease. Earlier studies on this disease are limited by small number of patients enrolled. The aim of the present study was to analyze the incidence, risk factors, clinical profile and long term outcome of patients with isolated LMCA ostial disease.

Methods

15,553 patients who underwent coronary angiogram in a single tertiary care cardiac hospital were analyzed for LMCA disease. 351(2.2%) patients were found to have significant LMCA disease out of which 28(0.18%) had isolated LMCA ostial disease. These 28 patients were compared with 323 non-ostial and non-isolated LMCA disease patients.

Results

The mean age of isolated LMCA ostial disease group was significantly less than the other group (p=0.009). Females were more affected than males (p=0.008). They also had low incidence of coronary risk factors (especially dyslipidemia, p=0.04). They tend to present more with stable angina and less with myocardial infarction. They had higher ejection fraction and normal regional wall motion (p=0.04). There was no mortality difference between two groups at the end of 1 year (p=0.234).

Conclusion

In one of the largest studies done in these patients, we found that isolated LMCA ostial disease is more common in middle aged females with few coronary risk factors. These patients also had a better ejection fraction and normal regional wall motion compared to patients with non-ostial and non-isolated LMCA disease. The clinical and angiographic profile of these patients suggests that they may represent a distinct clinical entity.

Resveratrol combined with total flavones of hawthorn alleviate the endothelial cells injury after coronary bypass graft surgery

OBJECTIVE

To explore the preventive and therapeutic effects of Resveratrol combined with total flavones of hawthorn, compatibility of traditional Chinese medicines, on the endothelial cells injury after artery bypass graft surgery.

METHODS

The animal model of coronary artery bypass grafting (CABG) was prepared by transplanting a segment of autologous jugular vein onto the transected common carotid artery in rabbits. After CABG surgery, the rabbits were administrated with saline (model group), aspirin (Aspirin group), resveratrol (Res group), total flavones of hawthorn (Haw group) and resveratrol combined with total flavones of hawthorn (Res+Haw group) once a day for eight weeks, respectively. Eight weeks later, the grafting arteries from all group were obtained for the pathomorphism observation, peripheral blood was collected to detect circulating endothelial cells (CECs) by flow cytometry. And the concentration of albumen and mRNA of ICAM-1 in the serum were measured by western blot and quantitative real-time polymerase chain reaction, respectively.

RESULTS

Compared with the model group, the level of CECs density and the expressions of albumen and mRNA of ICAM-1 were significantly decreased in the aspirin,resveratrol,total flavones of hawthorn and resveratrol combined with total flavones of hawthorn groups (P < .05). Of note, above all parameters were lower in Res group than aspirin group.

CONCLUSION

The Resveratrol combined with total flavones of hawthorn could protect the endothelial cells after coronary artery bypass graft.

Computer-Simulated Fluid Dynamics of Arterial Perfusion in Extracorporeal Circulation: From Reality to Virtual Simulation

Background

Atheroembolism due to aortic manipulation remains an unsolved problem in surgery for thoracic aortic aneurysm. The goal of the present study is to create a computer simulation (CS) model with which to analyze blood flow in the diseased aorta.

Method

A three-dimensional glass model of the aortic arch was constructed from CT images of a normal, healthy person and a patient with transverse aortic arch aneurysm. Separately, a CS model of the curved end-hole cannula was created, and flow from the aortic cannula was recreated using a numerical simulation.

Results

Comparison of the data obtained by the glass model analyses revealed that the flow velocity and the vector of the flow around the exit of the cannula were similar to that in the CS model. A high-velocity area was observed around the cannula exit in both the glass model and the CS model. The maximum flow velocity was as large as 1.0 m/s at 20 mm from the cannula exit and remained as large as 0.5 to 0.6 m/s within 50 mm of the exit. In the aortic arch aneurysm models, the rapid jet flow from the cannula moved straight toward the lesser curvature of the transverse aortic arch. The locations and intensities of the calculated vortices were slightly different from those obtained for the glass model.

Conclusions

The proposed CS method for the analysis of blood flow from the aortic cannulae during extracorporeal circulation can reproduce the flow velocity and flow pattern in the proximal and transverse aortic arches.

Oxygen uptake on-kinetics during six-minute walk test predicts short-term outcomes after off-pump coronary artery bypass surgery

PURPOSE

We aimed to investigate the ability of oxygen uptake kinetics to predict short-term outcomes after off-pump coronary artery bypass grafting.

METHODS

Fifty-two patients aged 60.9 ± 7.8 years waiting for off-pump coronary artery bypass surgery were evaluated. The 6-min walk test distance was performed pre-operatively, while simultaneously using a portable cardiopulmonary testing device. The transition of oxygen uptake kinetics from rest to exercise was recorded to calculate oxygen uptake kinetics fitting a monoexponential regression model. Oxygen uptake at steady state, constant time, and mean response time corrected by work rate were analysed. Short-term clinical outcomes were evaluated during the early post-operative of off-pump coronary artery bypass surgery.

RESULTS

Multivariate analysis showed body mass index, surgery time, and mean response time corrected by work rate as independent predictors for short-term outcomes. The optimal mean response time corrected by work rate cut-off to estimate short-term clinical outcomes was 1.51 × 10^-3 min²/ml. Patients with slower mean response time corrected by work rate demonstrated higher rates of hypertension, diabetes, EuroSCOREII, left ventricular dysfunction, and impaired 6-min walk test parameters. The per cent-predicted distance threshold of 66% in the pre-operative was associated with delayed oxygen uptake kinetics.

CONCLUSIONS

Pre-operative oxygen uptake kinetics during 6-min walk test predicts short-term clinical outcomes after off-pump coronary artery bypass surgery. From a clinically applicable perspective, a threshold of 66% of pre-operative predicted 6-min walk test distance indicated slower kinetics, which leads to longer intensive care unit and post-surgery hospital length of stay. Implications for rehabilitation Coronary artery bypass grafting is a treatment aimed to improve expectancy of life and prevent disability due to the disease progression; The use of pre-operative submaximal functional capacity test enabled the identification of patients with high risk of complications, where patients with delayed oxygen uptake kinetics exhibited worse short-term outcomes; Our findings suggest the importance of the rehabilitation in the pre-operative in order to "pre-habilitate" the patients to the surgical procedure; Faster oxygen uptake on-kinetics could be achieved by improving the oxidative capacity of muscles and cardiovascular conditioning through rehabilitation, adding better results following cardiac surgery.

Trends and Patterns of Corticosteroid Use During Coronary Artery Bypass Grafting Surgery in the United States

BACKGROUND

Several clinical trials have documented clinical benefits associated with prophylactic corticosteroid administration at the time of coronary artery bypass graft (CABG) surgery, including a reduction in the risk of atrial fibrillation and hospital length of stay. Despite the published data, the extent to which providers have adopted the perioperative use of corticosteroids remains unknown.

OBJECTIVES

To assess temporal trends, between-hospital variation, and determinants of perioperative intravenous corticosteroid use during CABG surgery.

METHODS

We identified all patients admitted for CABG surgery in the Premier Healthcare Database (2003-2014), a large US-based inpatient database. We determined the proportion of patients administered prophylactic corticosteroids on the day of CABG surgery. Linear time-series models were used to estimate the rate and trend of corticosteroid use over time. Separate multivariable generalized estimating equation models were used to quantify the variation in and determinants of perioperative corticosteroid use.

RESULTS

Of 401 788 eligible patients who underwent a CABG surgery between 2003 and 2014, 20% (n = 80 681) were administered intravenous prophylactic perioperative corticosteroids (methylprednisolone, dexamethasone, or hydrocortisone). Corticosteroid use increased from 17.5% in 2003 to 22.6% in 2014 (annual rate = 0.42%; P < .001). Individual hospitals accounted for >50% of variation in corticosteroid use. High between-hospital variation was also observed, and the probability of utilization was ≥32.4% in the upper versus ≤3.4% in the bottom quartiles of hospitals.

CONCLUSION

Prophylactic corticosteroid administration during CABG has increased gradually since 2003. To further evaluate the risk-benefit trade-off associated with their use, we believe a large-scale outcomes study is warranted to assess this highly variable practice.

The Influence of Comprehensive Cardiac Rehabilitation on Heart Rate Variability Indices after CABG is More Effective than after PCI

The aim of this study was to evaluate the influence of cardiac rehabilitation (CR) on heart rate variability (HRV) indices in men with coronary artery disease (CAD) treated with percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG). The study population consisted of 131 male patients with CAD prospectively and consecutively admitted to CR after PCI n = 72, or CABG n = 59. Participants performed cycle ergometer interval training for 45 min three times a week for 8 weeks. At baseline and after 8 weeks, all patients underwent the HRV assessment. HRV indices in CAGB survivals were significantly lower in comparison to PCI patients at baseline. Significant increases were seen for SDNN, rMSSD, and HF in the CABG group and only in HF component in PCI group after 8 weeks of CR. Eight weeks of CR seems to be more effective in CABG patients than patients after PCI.

Diagnostic accuracy of 256-row multidetector CT coronary angiography with prospective ECG-gating combined with fourth-generation iterative reconstruction algorithm in the assessment of coronary artery bypass: evaluation of dose reduction and image quality

BACKGROUND

Effective radiation dose in coronary CT angiography (CTCA) for coronary artery bypass graft (CABG) evaluation is remarkably high because of long scan lengths. Prospective electrocardiographic gating with iterative reconstruction can reduce effective radiation dose.

OBJECTIVES

To evaluate the diagnostic performance of low-kV CT angiography protocol with prospective ecg-gating technique and iterative reconstruction (IR) algorithm in follow-up of CABG patients compared with standard retrospective protocol.

METHODS

Seventy-four non-obese patients with known coronary disease treated with artery bypass grafting were prospectively enrolled. All the patients underwent 256 MDCT (Brilliance iCT, Philips) CTCA using low-dose protocol (100 kV; 800 mAs; rotation time: 0.275 s) combined with prospective ECG-triggering acquisition and fourth-generation IR technique (iDose⁴; Philips); all the lengths of the bypass graft were included in the evaluation. A control group of 42 similar patients was evaluated with a standard retrospective ECG-gated CTCA (100 kV; 800 mAs).On both CT examinations, ROIs were placed to calculate standard deviation of pixel values and intra-vessel density. Diagnostic quality was also evaluated using a 4-point quality scale.

RESULTS

Despite the statistically significant reduction of radiation dose evaluated with DLP (study group mean DLP: 274 mGy cm; control group mean DLP: 1224 mGy cm; P value < 0.001). No statistical differences were found between PGA group and RGH group regarding intra-vessel density absolute values and SNR. Qualitative analysis, evaluated by two radiologists in "double blind", did not reveal any significant difference in diagnostic quality of the two groups.

CONCLUSIONS

The development of high-speed MDCT scans combined with modern IR allows an accurate evaluation of CABG with prospective ECG-gating protocols in a single breath hold, obtaining a significant reduction in radiation dose.

Diagnostic accuracy of chest X-ray dose-equivalent CT for assessing calcified atherosclerotic burden of the thoracic aorta

OBJECTIVE

To determine the value of ultralow-dose chest CT for estimating the calcified atherosclerotic burden of the thoracic aorta using tin-filter CT and compare its diagnostic accuracy with chest direct radiography.

METHODS

A total of 106 patients from a prospective, IRB-approved single-centre study were included and underwent standard dose chest CT (1.7 ± 0.7 mSv) by clinical indication followed by ultralow-dose CT with 100 kV and spectral shaping by a tin filter (0.13 ± 0.01 mSv) to achieve chest X-ray equivalent dose in the same session. Two independent radiologists reviewed the CT images, rated image quality and estimated presence and extent of calcification of aortic valve, ascending aorta and aortic arch. Conventional radiographs were also reviewed for presence of aortic calcifications.

RESULTS

The sensitivity of ultralow-dose CT for the detection of calcifications of the aortic valve, ascending aorta and aortic arch was 93.5, 96.2 and 96.2%, respectively, compared with standard dose CT. The sensitivity for the detection of thoracic aortic calcification was significantly lower on chest X-ray (52.3%) compared with ultralow-dose CT (p < 0.001).

CONCLUSION

A reliable estimation of calcified atherosclerotic burden of the thoracic aorta can be achieved with modern tin-filter CT at dose values comparable to chest direct radiography. Advances in knowledge: Our findings suggest that ultralow-dose CT is an excellent tool for assessing the calcified atherosclerotic burden of the thoracic aorta with higher diagnostic accuracy than conventional chest radiography and importantly without the additional cost of increased radiation dose.

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.

The Surgical Treatment of Coronary Artery Occlusive Disease: Modern Treatment Strategies for an Age Old Problem

Coronary artery disease remains a formidable challenge to clinicians. Percutaneous interventions and surgical techniques for myocardial revascularization continue to improve. Concurrently, in light of emerging data, multiple practice guidelines have been published guiding clinicians in their therapeutic decisions. The multidisciplinary Heart Team concept needs to be embraced by all cardiovascular providers to optimize patient outcomes.

Successful hybrid coronary artery revascularisation in a patient with severe cerebrovascular disease: a new treatment option to minimise the risk of stroke

Here we present a case involving a patient with severe distal left main coronary artery stenosis with extensive coexisting extracranial cerebrovascular disease where hybrid coronary artery revascularisation was successfully performed. This illustrates the potential for hybrid revascularisation in those patients with an inherit risk of stroke.

Fractional flow reserve in 2017: current data and everyday practice

INTRODUCTION

Fractional flow reserve (FFR) is an objective physiological index utilized in coronary angiography. It expresses the blood flow in the presence of a coronary artery stenosis as a fraction of the normal blood flow and gives information regarding the functional significance of the lesion. FFR guided percutaneous coronary intervention (PCI) has been shown to be superior to angiography guided PCI in several trials and registries. In addition, it appears that the use of FFR may also be preferable from an economic perspective. Areas covered: This article will cover the physiological principles underpinning FFR, the landmark clinical trials that have established its diagnostic utility and the current recommendations for the use of the procedure in daily practice. We will also examine potential future directions for the technology and try to predict how its use will evolve in the next five years. Expert commentary: We see FFR as an essential diagnostic tool in the modern catheterization laboratory, enabling physicians to make optimal decisions regarding percutaneous coronary intervention for an individual patient. It must be stated however that FFR is an adjunctive invasive functional tool that must be used in conjunction with sensible clinical history and exam findings pertaining to the individual patient. We expect that the results of FAME3 will further establish the role of FFR in risk stratifying patients with 3 vessel disease by utilizing a functional SYNTAX score.

Fractional Flow Reserve and Cardiac Events in Coronary Artery Disease: Data From a Prospective IRIS-FFR Registry (Interventional Cardiology Research Incooperation Society Fractional Flow Reserve)

BACKGROUND

We evaluated the prognosis of deferred and revascularized coronary stenoses after fractional flow reserve (FFR) measurement to assess its revascularization threshold in clinical practice.

METHODS

The IRIS-FFR registry (Interventional Cardiology Research In-cooperation Society Fractional Flow Reserve) prospectively enrolled 5846 patients with ≥1coronary lesion with FFR measurement. Revascularization was deferred in 6468 lesions and performed in 2165 lesions after FFR assessment. The primary end point was major adverse cardiac events (cardiac death, myocardial infarction, and repeat revascularization) at a median follow-up of 1.9 years and analyzed on a per-lesion basis. A marginal Cox model accounted for correlated data in patients with multiple lesions, and a model to predict per-lesion outcomes was adjusted for confounding factors.

RESULTS

For deferred lesions, the risk of major adverse cardiac events demonstrated a significant, inverse relationship with FFR (adjusted hazard ratio, 1.06; 95% confidence interval, 1.05-1.08; P<0.001). However, this relationship was not observed in revascularized lesions (adjusted hazard ratio, 1.00; 95% confidence interval, 0.98-1.02; P=0.70). For lesions with FFR ≥0.76, the risk of major adverse cardiac events was not significantly different between deferred and revascularized lesions. Conversely, in lesions with FFR ≤0.75, the risk of major adverse cardiac events was significantly lower in revascularized lesions than in deferred lesions (for FFR 0.71-0.75, adjusted hazard ratio, 0.47; 95% confidence interval, 0.24-0.89; P=0.021; for FFR ≤0.70, adjusted hazard ratio 0.47; 95% confidence interval, 0.26-0.84; P=0.012).

CONCLUSIONS

This large, prospective registry showed that the FFR value was linearly associated with the risk of cardiac events in deferred lesions. In addition, revascularization for coronary artery stenosis with a low FFR (≤0.75) was associated with better outcomes than the deferral, whereas for a stenosis with a high FFR (≥0.76), medical treatment would be a reasonable and safe treatment strategy.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01366404.