Long-term clinical and angiographic outcomes in patients with diabetes undergoing coronary artery bypass graft surgery: results from the Project of Ex-vivo Vein Graft Engineering via Transfection IV trial

Surgical ablation for atrial fibrillation: impact of Diabetes Mellitus type 2

BACKGROUND

Diabetes mellitus (DM) type 2 is an independent risk factor for atrial fibrillation (AF). Surgical ablation or "maze procedure" is an option for patients with AF undergoing concomitant or isolated cardiac surgery. The aim of this study was to evaluate the impact of DM type 2 on early and long-term outcomes of patients following surgical AF ablation.

METHODS

We performed an observational cohort study in Israel's largest tertiary care center. All data of patients who underwent surgical AF ablation, between 2006 and 2021 were extracted from our departmental database. Patients were divided into Group I (non-diabetic patients) and Group II (DM type 2 patients). We compared the two groups with respect to freedom from recurrent atrial arrhythmia, and mortality rate.

RESULTS

The study population included 606 patients. Group I (non-DM patients), consisting of 484 patients, and Group II (DM type 2 patients), comprised 122 patients. Patients with DM were older, had more hypertension and incidence of cerebrovascular accident (CVA)/transient ischemic attack (TIA), higher EuroSCORE (p < .05 for all), and a longer bypass time-130 ± 40 vs. 122 ± 36 min (p = 0.028). The mean follow-up duration was 39.0 ± 22.7 months. Freedom from atrial fibrillation was similar between the non-DM and DM type 2 groups after a 1-year follow-up, 414 (88.2%) vs. 101 (87.1%) (p = 0.511), after a 3-year follow-up, 360 (86.3%) vs. 84 (79.9%) (p = 0.290) and after a 5-year follow-up, 226 (74.1%) vs. 55 (71.5%) (p = 0.622) respectively. Furthermore, 1- and 3-year mortality was similar between non-DM and DM type 2 groups, 2.5% vs. 4.9%, (p = 0.226) and 5.6% vs. 10.5% (p = 0.076) respectively. 5-year mortality was higher in Group II (DM type 2 patients) compared with Group I (non-DM patients), 11.1% vs. 23.4% (p = 0.009).

CONCLUSION

Surgical ablation had a high success rate, with freedom from recurrent atrial arrhythmia at 1- 3- and 5- years follow-up in both the DM type 2 and non-DM groups. Furthermore,1- and 3-year mortality after surgical ablation was also similar in both groups. However, 5-year mortality was higher in the DM type 2 group.

Impact of diabetes mellitus on long-term clinical and graft outcomes after off-pump coronary artery bypass grafting with pure bilateral skeletonized internal thoracic artery grafts

BACKGROUND

The effect of diabetes mellitus (DM) on the long-term outcomes of coronary artery bypass graft (CABG) remained debatable and various strategies exist for CABG; hence, clarifying the effects of DM on CABG outcomes is difficult. The current study aimed to evaluate the effect of DM on clinical and graft-related outcomes after CABG with bilateral internal thoracic artery (BITA) grafts.

METHODS

From January 2001 to December 2017, 3395 patients who underwent off-pump CABG (OPCAB) with BITA grafts were enrolled. The study population was stratified according to preoperative DM. The primary endpoint was cardiac death and the secondary endpoints were myocardial infarction (MI), revascularization, graft failure, stroke, postoperative wound infection, and a composite endpoint of cardiac death, MI, and revascularization. Multiple sensitivity analyses, including Cox proportional hazard regression and propensity-score matching analyses, were performed to adjust baseline differences.

RESULTS

After CABG, the DM group showed similar rates of cardiac death, MI, or revascularization and lower rates of graft failure at 10 years (DM vs. non-DM, 19.0% vs. 24.3%, hazard ratio [HR] 0.711, 95% confidence interval [CI] 0.549-0.925; P = 0.009) compared to the non-DM group. These findings were consistent after multiple sensitivity analyses. In the subgroup analysis, the well-controlled DM group, which is defined as preoperative hemoglobin A1c (HbA1c) of < 7%, showed lower postoperative wound infection rates (well-controlled DM vs. poorly controlled DM, 3.7% vs. 7.3%, HR 0.411, 95% CI 0.225-0.751; P = 0.004) compared to the poorly controlled DM group, which was consistent after propensity-score matched analysis.

CONCLUSIONS

OPCAB with BITA grafts showed excellent and comparable long-term clinical outcomes in patients with and without DM. DM might have a protective effect on competition and graft failure of ITA. Strict preoperative hyperglycemia control with target HbA1c of < 7% might reduce postoperative wound infection and facilitate the use of BITA in CABG.

A five-parameter score for predicting saphenous vein graft degenerative and/or occlusive disease in recurring ischemic symptoms after one year post coronary artery bypass grafting

BACKGROUND

The recurrence rate of ischemic symptoms after coronary artery bypass grafting (CABG) is increasing in recent years. How to prevent and treat saphenous vein graft disease (SVGD [symptomatic ⩾50% stenosis in at least one Saphenous vein graft]) has been a clinical challenge to date. Different pathogenesis may exist in SVGD of different periods. There are currently few available scores for estimating the risk of SVGD after one year post CABG.

OBJECTIVE

We sought to develop and validate a simple predictive clinical risk score for SVGD with recurring ischemia after one year post CABG.

METHODS AND RESULTS

This was a cross-sectional study and the results were validated using bootstrap resampling on a separate cohort. A nomogram and risk scoring system were developed based on retrospective data from a training cohort of 606 consecutive patients with recurring ischemia >1 year after CABG. Logistic regression model was used to find the predictive factors and to build a nomogram. To assess the generalization, models were validated using bootstrap resampling and an external cross-sectional study of 187 consecutive patients in four other hospitals. In multivariable analysis of the primary cohort, native lesion vessel number, SVG age, recurring ischemia type, very low-density lipoprotein level, and left ventricular end-diastolic diameter were independent predictors. A summary risk score was derived from nomogram, with a cut-off value of 15. In internal and external validation, the C-index was 0.86 and 0.82, indicating good discrimination. The calibration curve for probability of SVGD showed optimal agreement between actual observations and risk score prediction.

CONCLUSION

A simple-to-use risk scoring system based on five easily variables was developed and validated to predict the risk of SVGD among patients who recurring ischemia after one year post CABG. This score may be useful for providing patients with individualized estimates of SVGD risk.

Influence of Baseline HbA1c and Antiplatelet Therapy on 1-Year Vein Graft Outcome

BACKGROUND

The influence of baseline HbA1c levels on vein graft outcomes post coronary artery bypass grafting (CABG) remains unclear.

OBJECTIVE

The purpose of this study was to assess the association between baseline HbA1c and 1-year vein graft patency, and the effects of antiplatelet therapy on the 1-year vein graft patency after CABG in patients with baseline HbA1c <6.5% vs ≥6.5%.

METHODS

We examined the subgroups with baseline HbA1c <6.5% vs ≥6.5% from the DACAB trial (NCT02201771), in which 500 patients were randomly allocated to receive ticagrelor plus aspirin (T+A), ticagrelor alone (T), or aspirin alone (A) for 1 year after CABG. The primary outcome was the vein graft patency (FitzGibbon grade A) at 1 year.

RESULTS

A total of 405 patients with available baseline HbA1c data were included in this subgroup analysis. Of them, there were 233 patients (678 vein grafts) with baseline HbA1c <6.5% and 172 patients (512 vein grafts) with baseline HbA1c ≥6.5%. Compared with the HbA1c <6.5% subgroup, the HbA1c ≥6.5% subgroup showed worse 1-year vein graft patency (adjusted odds ratio [OR] for nonpatency: 1.69, 95% confidence interval [CI]: 1.08-2.64). T+A showed higher vein graft patency than A in both HbA1c <6.5% (adjusted OR for nonpatency: 0.34, 95% CI: 0.15-0.75) and HbA1c ≥6.5% subgroups (adjusted OR for nonpatency: 0.45, 95% CI: 0.19-1.09), without an interaction effect (P for interaction = 0.335), whereas T did not show more significant improvement than A in both subgroups.

CONCLUSIONS

In the DACAB trial, lower baseline HbA1c was associated with higher vein graft patency 1 year after CABG. T+A improved 1-year vein graft patency vs A, irrespective of baseline HbA1c.

Impact of Atherogenic Indexes in Saphenous Vein Graft Stenosis

Fundamento

Os enxertos de veias safenas (EVS) são frequentemente usados em pacientes submetidos a cirurgia de revascularização do miocárdio (CRM).

Objetivos

Avaliar as relações entre índices aterogênicos e estenose de EVS. Métodos: No total, 534 pacientes (27,7% mulheres, com idade média de 65±8,4 anos) submetidos a CRM e angiografia coronariana eletiva foram incluídos no estudo. Pacientes com pelo menos uma estenose EVS ≥50% foram alocados ao grupo estenose EVS (+) (n=259) e pacientes sem estenose foram classificados como EVS (-) (n=275). O índice aterogênico plasmático (IAP) e o coeficiente aterogênico (CA) foram calculados a partir dos parâmetros lipídicos de rotina dos pacientes. A significância foi estabelecida no nível p<0,05.

Resultados

O número de pacientes com histórico de hipertensão (HT), diabetes mellitus (DM), acidente vascular cerebral e insuficiência cardíaca (IC) se mostrou significativamente maior no grupo EVS (+) do que no grupo EVS (-). O colesterol total, triglicerídeos e colesterol LDL mostraram-se significativamente mais altos e o colesterol HDL mostrou-se menor no grupo EVS (+) do que no grupo EVS (-). IAP (p<0,001) e CA (p<0,001) apresentaram-se significativamente mais altos no grupo EVS (+) do que no grupo EVS (-). A análise ROC mostra que tanto o IAP quanto o CA mostraram-se melhores que o colesterol HDL, colesterol LDL e colesterol não HDL na predição de estenose de EVS. Na análise multivariada, histórico de DM, HT, acidente vascular cerebral, IC, número de enxertos de safena, colesterol HDL, colesterol LDL, colesterol não HDL, IAP e CA foram fatores de risco independentes para estenose de EVS.

Conclusão

O IAP e o CA foram preditores independentes de estenose de EVS. Além disso, tanto o IAP quanto o CA têm melhor desempenho na predição de estenose de EVS do que o colesterol LDL, colesterol HDL e colesterol não HDL. (Arq Bras Cardiol. 2020; 115(3):538-544)

Role of Urotensin-II in Saphenous Vein Graft Disease

Objective

To elucidate the effect of diabetes mellitus (DM) on the atherosclerotic process in saphenous vein grafts by determining urotensin-II (U-II) levels in harvested saphenous veins of patients who underwent coronary artery bypass grafting (CABG).

Methods

Coronary artery disease (CAD) patients who underwent CABG were divided into two groups: Group I (eight non-diabetic patients; CAD group) and Group II (13 patients; DM+CAD group). All patients underwent coronary angiography prior to surgery and Gensini score was used to determine the severity of coronary atherosclerosis. Saphenous vein samples were stained with hematoxylin-eosin and U-II, then damage score, H-Score, and vein layer thicknesses were calculated and statistically evaluated.

Results

In light microscopic evaluation, significant difference was observed between the groups in terms of endothelial cells damage, internal elastic lamina degradation, and tunica media vascular smooth muscle cells (VSMCs) damage (P<0.001). U-II immunoreactivity was increased in tunica adventitia in the DM+CAD group (P=0.002). The increase in foam cells was directly proportional to the thickening of the subendothelial layer, and this increased U-II immunoreactivity. Gensini score was higher in the DM+CAD group than in the CAD group (P=0.002).

Conclusion

Our results show that saphenous vein grafts are already atherosclerotic before they are grafted in CAD patients. This disease is more severe in diabetic CAD patients and these changes can be detected using U-II immunoreactivity.

Type 2 diabetes mellitus increases the mortality risk after acute coronary syndrome treated with coronary artery bypass surgery

Background

Type 2 diabetes mellitus (DM) is a risk factor for cardiovascular diseases and is common among patients undergoing coronary artery bypass grafting (CABG) surgery. The main objective of our study was to investigate the impact of DM type 2, and its treatment subgroups, on short- and long-term mortality in patients with acute coronary syndrome (ACS) who undergo CABG.

Methods

The study included 1307 patients enrolled from the biennial Acute Coronary Syndrome Israeli Survey between 2000 and 2016, who were hospitalized for ACS and underwent CABG. Of them, 527 (40%) patients were with and 780 (60%) were without DM.

Results

Compared with the non-diabetic group, the diabetic group of patients comprised more women and had more comorbidities such as hypertension, dyslipidemia, renal impairment, peripheral vascular disease and prior ischemic heart disease. Overall 30-day mortality rate was similar between DM and non-DM patients (4.2% vs. 4%, p = 0.976). Ten-year mortality rate was higher in DM compared with non-diabetic patients (26.6% vs. 17.7%, log-rank p < 0.001), and higher in the subgroup of insulin-treated patients compared to non-insulin treated patients (31.5% vs. 25.6%, log-rank p = 0.019). Multivariable analysis showed that DM increased the mortality hazard by 1.61-fold, and insulin treatment among the diabetic patients increased the mortality hazard by 1.57-fold.

Conclusions

While type 2 DM did not influence the in-hospital mortality hazard, we showed that the presence of DM among patients with ACS referred to CABG, is a powerful risk factor for long-term mortality, especially when insulin was included in the diabetic treatment strategy.

Coronary artery bypass surgery in type 2 diabetic patients: predictors of mortality and morbidity

Background

Coronary artery bypass grafting has been widely admitted in the therapeutic arsenal of coronary artery disease in diabetics with low morbi-mortality. However, it requires special management which may be challenging in low-volume centers especially in African countries. We aimed to analyze the outcome of coronary artery bypass graft in our diabetic population and define predictors of adverse events.

Patients and methods

We retrospectively enrolled 529 consecutive diabetic patients (type 2) who underwent on-pump coronary artery bypass grafting at our institution between January 2000 and June 2018. The mean age was 61.1 ± 8.3 years with 4.04 as sex ratio (M/F) and 2.95 as mean EuroSCORE II. History of acute myocardial infarction, left main coronary artery stenosis, and three-vessel disease was present in respectively 58%, 26.1%, and 72.2% of patients. The average number of bypass was 2.4 ± 0.8. Duration of cardiopulmonary bypass and aortic cross-clamping were respectively 124.8 ± 43.5 and 79.7 ± 32.9 min.

Results

In-hospital mortality was 5.9% (n = 31) and the late mortality was 6.9% (n = 32). Duration of artificial ventilation, ICU stay, and postoperative stay were respectively 7 h, 44 h, and 13 days. Postoperative complications were myocardial infarction, superficial wound infection, mediastinitis, and low cardiac output syndrome in respectively 9.1%, 25.5%, 3.8%, and 12.7% of patients. Multivariable logistic regression analysis revealed that left ventricular ejection fraction < 40% (OR = 1.88; 95% CI 1.30–2.47; p = 0.03), poor perioperative glycemic control (OR = 1.53; 95% CI 1.12–2.38; p = 0.014), intra-aortic balloon pump insertion (OR = 2.29; 95% CI 1.47–3.10; p < 0.001), and postoperative cardiac complications (OR = 2.01; 95% CI 1.23–2.78; p < 0.001) were predictors of in-hospital mortality. Predictors of mediastinitis were obesity (OR = 5.86; 95% CI 1.43–23.95; p = 0.014), inotropic drugs use (OR = 8.14; 95% CI 1.57–42.34; p = 0.013), chest reopening for bleeding (OR = 4.01; 95% CI 0.62–25.85; p = 0.014), and blood transfusion (OR = 7.56; 95% CI 1.09–52.76; p = 0.041). Follow-up was 86.1% complete, with a mean follow-up of 63.5 ± 48.3 months (1–192 months), and cumulative survival at 5, 10, and 15 years was respectively 95.5 ± 1.1%, 86.3 ± 2.9%, and 76.9 ± 6.9%.

Conclusion

Even in low-volume centers in developing areas, coronary artery bypass surgery is an effective therapy for coronary artery disease in diabetic patients despite a relative high morbidity and mortality.

Left ventricular function outcome after coronary artery bypass grafting, King Abdullah Medical City (KAMC)- single-center experience

Background

Coronary artery bypass grafting is known to be associated with better outcome in ischemic heart disease patients with low ejection fraction. We aim to demonstrate the effect of coronary artery bypass grafting (CABG) on left ventricle (LV) systolic function and to identify the predictors that adversely lead to postoperative poor outcome.

Result

This is a cross-sectional prospective study; we included 110 patients with left ventricular ejection fraction (LVEF) < 50% who underwent CABG with a mean age of 56.1 ± 12.2 years old. Those patients were classified into two groups: group I, 76 (69%) patients with LVEF > 35%, and group II, 34 (31%) patients with LVEF < 35%. Our results as regards demographic and clinical data revealed that group II patients had a significantly higher prevalence of diabetes mellitus (DM) and Euro SCORE II compared to group I patients (p = 0.05 and < 0.001 respectively); otherwise, all other clinical predictors did not differ between the two studied groups. There was a significant improvement in LVEF post-surgery (p = 0.05) in both groups with observed no significant difference recorded for in-hospital mortality rate among patients with different groups. DM, significant diastolic dysfunction, and insertion of IABP are predictors of in-hospital mortality of the patients (p = 0.001, 0.03 and < 0.001, respectively)

Conclusion

We concluded that there is a significant improvement of LV systolic function after CABG and hence better survival rate. DM, significant diastolic dysfunction, and perioperative insertion of IABP are predictors of mortality after cardiac surgery. Special care should be provided to such patients to improve their outcome

Impact of type 2 diabetes mellitus on short- and long-term mortality after coronary artery bypass surgery

Background

Type 2 diabetes mellitus (DM) is a frequent co-morbidity among patients undergoing coronary artery bypass grafting (CABG) surgery. The aim of this study was to evaluate the impact of DM on the early- and long-term outcomes of patients who underwent isolated CABG.

Methods

We performed an observational cohort study in a large tertiary medical center over a period of 11 years. All data from patients who had undergone isolated CABG surgery between 2004 and 2014 were obtained from our departmental database. The study population included 2766 patients who were divided into two groups: Group I (1553 non-diabetic patients), and Group II (1213 patients suffering from type 2 DM). Group II patients were then divided into two subgroups: subgroup IIA (981 patients treated with oral antihyperglycemic medications) and subgroup IIB (232 insulin-treated patients with or without additional oral antihyperglycemic drugs). In-hospital, 1-, 3-, 5- and 10-year mortality outcome variables were evaluated. Mean follow-up was 97 ± 41 months.

Results

In-hospital mortality was similar between Group I and Group II patients (1.87% vs. 2.31%, p = 0.422) and between the subgroups IIA and IIB (2.14% vs. 3.02%, p = 0.464). Long-term mortality (1, 3, 5 and 10 years) was higher in Group II (DM type 2) compared with Group I (non-diabetic patients) (5.3% vs. 3.6%, p = 0.038; 9.3% vs. 5.6%, p < 0.001; 15.3% vs. 9.3%, p < 0.001 and 47.3% vs. 29.6% p < 0.001). Kaplan–Meier analysis demonstrated that all-cause mortality was higher in Group II compared with Group I (p < 0.001) and in subgroup IIB compared with subgroup IIA (p = 0.001). Multivariable analysis showed that DM increased the mortality hazard by twofold, and among diabetic patients, insulin treatment increased the mortality hazard by twofold.

Conclusions

Diabetic and non-diabetic patients have similar in-hospital mortality rates. Survival rates of diabetic patients start to deteriorate 3 year after surgery. Type 2 DM is an independent predictor for long-term mortality after isolated CABG surgery. Mortality is even higher when the diabetes treatment strategy included insulin.

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0796-7) contains supplementary material, which is available to authorized users.

Review of risk factors, treatment, and prevention of saphenous vein graft disease after coronary artery bypass grafting

Saphenous vein graft disease (SVGD) is a type of vascular disease that may develop after coronary artery bypass grafting (CABG). SVGD seriously affects the short-term and long-term effects of CABG and increases the incidence of major adverse cardiovascular events. It is very important to identify patients at greatest risk and carry out prevention and treatment measures to determine the risk factors for SVGD. Many factors contribute to SVGD when the vein is grafted into an arterial environment, such as surgery-related factors, smoking, diabetes mellitus, hyperlipidemia, and others. In this review, we discuss the risk factors for SVGD, current surgical and pharmacologic therapies with which to manage SVGD, and the prevention of SVGD.

Which factor is the most effective one in metabolic Sydrome on the outcomes after coronary artery bypass graft surgery? A cohort study of 5 Years

Background

Metabolic Syndrome and diabetes mellitus are risk factors for cardiovascular disease. However, the effects of Metabolic Syndrome with or without diabetes on perioperative and long-term morbidity and mortality after Coronary Artery Bypass Graft remain unclear.

Methods

An retrospective study was performed on 1166 patients who received isolated primary Coronary Artery Bypass Graft in Fuwai hospital. They were divided into three groups: control, Metabolic Syndrome of three factors together with diabetes and Metabolic Syndrome of three factors without diabetes (n = 868, 76 and 222 respectively). Analysis of variance, Chi-rank test, Fisher’s exact test, Log-rank test, Cox and Logistic regression models were used for data processing. Outcomes were postoperative and 5-year survival and morbidities.

Results

There were no significant differences between groups in in-hospital postoperative complications, epinephrine use, stroke, atrial fibrillation, renal failure, coma, myocardial infarction and repeated revascularization. Patients in the Metabolic Syndrome with diabetes, Metabolic Syndrome without diabetes and control groups, respectively, showed significant difference in perioperative Major Adverse Cerebral Cardiovascular Events (30.3% vs. 21.2%, 16.7%, P = 0.0071) and mortality (11.8% vs. 2.7%, 3.11%, P = 0.0003). The Metabolic Syndrome with diabetes group had higher rates of perioperative mortality than Metabolic Syndrome without diabetes (P = 0.0017, P of Fisher Test = 0.0039). Compared with non-diabetic patients with Metabolic Syndrome, those with Metabolic Syndrome and diabetes had increased long-term mortality (Adjusted HR: 4.3; 95% CI: 1.4–13.3; P = 0.0113) and Major Adverse Cerebral Cardiovascular Events (Adjusted OR: 1.7; 95% CI: 1.0–2.8; P = 0.048). Control and non-diabetic Metabolic Syndrome groups did not differ in long-term mortality but controls had lower rates of Major Adverse Cerebral Cardiovascular Events (Adjusted OR: 0.79; 95% CI: 0.64–0.98; P = 0.0329).

Conclusions

There were significance differences between the three groups in perioperative Major Adverse Cerebral Cardiovascular Events and mortality after Coronary Artery Bypass Graft. Compared with non-diabetic Metabolic Syndrome patients, patients with Metabolic Syndrome and diabetes had higher long-term Major Adverse Cerebral Cardiovascular Events and mortality. While patients free of MetS and diabetes were associated with lower incidence of long-term Major Adverse Cerebral Cardiovascular Events after Coronary Artery Bypass Graft.

Haptoglobin 2-2 Phenotype Is Associated With Increased Acute Kidney Injury After Elective Cardiac Surgery in Patients With Diabetes Mellitus

BACKGROUND

Recent studies reported an association between the 2-2 phenotype of haptoglobin (Hp 2-2) and increased cardiorenal morbidity in nonsurgical diabetic patients. Our goal was to determine whether the Hp 2-2 phenotype was associated with acute kidney injury (AKI) after elective cardiac surgery in patients with diabetes mellitus.

METHODS AND RESULTS

We prospectively enrolled 99 diabetic patients requiring elective cardiac surgery with cardiopulmonary bypass. Haptoglobin phenotypes were determined by gel electrophoresis. Cell-free hemoglobin, haptoglobin, and total serum bilirubin were quantified as hemolysis markers. The primary outcome was postoperative AKI, as defined by the Acute Kidney Injury Network classification. The incidence of AKI was significantly higher in Hp 2-2 patients compared with patients without this phenotype (non-Hp-2-2; 55.6% versus 27%, P<0.01). The need for renal replacement therapy was also significantly higher in the Hp 2-2 group (5 patients versus 1 patient, P=0.02). Thirty-day mortality (3 versus 0 patients, P=0.04) and 1-year mortality (5 versus 0 patients, P<0.01) were also significantly higher in patients with the Hp 2-2 phenotype. In multivariable analysis, Hp 2-2 was an independent predictor of postoperative AKI (P=0.01; odds ratio: 4.17; 95% confidence interval, 1.35-12.48).

CONCLUSIONS

Hp 2-2 phenotype is an independent predictor of postoperative AKI and is associated with decreased short and long-term survival after cardiac surgery in patients with diabetes mellitus.

Impact of type 2 diabetes mellitus on the long-term mortality in patients who were treated by coronary artery bypass surgery: A systematic review and meta-analysis

BACKGROUND

Recent scientific reports have mainly focused on the comparison between coronary artery bypass surgery (CABG) and percutaneous coronary intervention. However, the impact of type 2 diabetes mellitus (T2DM) on mortality in patients who were treated by CABG was often ignored. Therefore, we aimed to compare the long-term mortality following CABG in patients with and without T2DM.

METHODS

Studies comparing the long-term adverse outcomes following CABG in patients with and without T2DM were searched from electronic databases. Total number of deaths (primary outcome) and events of myocardial infarction (MI), major adverse cerebrovascular and cardiovascular events (MACCEs), stroke, and repeated revascularization (secondary outcomes) were carefully extracted. An analysis was carried out whereby odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the RevMan 5.3 software.

RESULTS

Eleven studies with a total number of 12,965 patients were included. Current results showed that mortality was significantly higher in patients with T2DM with OR: 1.54, 95% CI: 1.37 to 1.72, P < .00001; OR: 1.53, 95% CI: 1.36 to 1.72, P < .00001; and OR: 1.53, 95% CI: 1.26 to 1.87, P < .0001 at 1 to 15, 5 to 15, and 7 to 15 years, respectively. However, MI, repeated revascularization, MACCEs, and stroke were not significantly different with OR: 1.15, 95% CI: 0.81 to 1.64, P = .44; OR: 1.09, 95% CI: 0.88 to 1.36, P = .43; OR: 1.11, 95% CI: 0.83 to 1.48, P = .48; and OR: 1.69, 95% CI: 0.93 to 3.07, P = .08, respectively.

CONCLUSION

Following CABG, a significantly higher rate of mortality was continually observed in patients with T2DM compared to patients without T2DM showing that the former apparently has a high impact on the long-term mortality. However, even if T2DM is an independent risk factor for mortality, it should not be ignored that CABG remains the best revascularization strategy in these patients.

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.

Advanced glycation end products impair the functions of saphenous vein but not thoracic artery smooth muscle cells through RAGE/MAPK signalling pathway in diabetes

Saphenous vein (SV) and internal thoracic artery (ITA) are commonly used bypass conduits. However, graft failure occurs in SV rather than in ITA, especially in diabetes (DM). The mechanism for this difference has not been fully understood. Accumulation of advanced glycation end products (AGEs) and activation of AGEs receptor (RAGE) could accelerate smooth muscle cells (SMC) proliferation in DM, we thus asked whether AGEs-RAGE could mediate the differences between SMC from SV (SMCV ) and from ITA (SMCA ). Twenty-five patients with DM and other 25 patients without DM were enclosed in DM and control group, respectively. AGEs (100 μg/ml) were added to cultured SMCA and SMCV obtained at coronary artery bypass graft (CABG) and proliferative rates were determined. Transcript expression, phosphorylation or protein expression levels of MAP kinase family (ERK, p38 and JNK), matrix metalloproteinases (MMP)-2 and MMP-9 were analysed by real-time PCR, Western-blot or immunofluorescence staining, respectively. Compared with paired SMCA , SMCV showed significantly increased proliferation rate, MAP kinase family phosphorylation, and MMP-2/9 expression in both groups, especially in DM group. The responses of SMCV induced by AGEs were significantly larger in DM than in control group, which could be suppressed by inhibition of RAGE and ERK. However, all the cellular events of SMCV were not found in paired SMCA . This study suggests that AGEs-RAGE could induce the proliferation of SMCV but not SMCA via MAP kinase pathway in DM. It is the intrinsic 'inactive' tendency of SMCA that contributes to the different rates of graft disease between SV and ITA after CABG.

Comparing the Clinical Outcomes Between Insulin-treated and Non-insulin-treated Patients With Type 2 Diabetes Mellitus After Coronary Artery Bypass Surgery: A Systematic Review and Meta-analysis

Several studies have shown coronary artery bypass surgery (CABG) to be beneficial in patients with type 2 diabetes mellitus (T2DM) and multivessel coronary artery diseases. Patients with insulin-treated T2DM (ITDM) are usually patients with poor glycemic control and are expected to suffer more complications compared with patients with non-insulin-treated T2DM (NITDM). However, the adverse clinical outcomes in patients with ITDM and NITDM after CABG are still not very clear. Hence, to solve this issue, we aim to compare the short-and long-term adverse clinical outcomes in a larger number of patients with ITDM and NITDM after CABG, respectively.Randomized controlled trials and observational studies comparing the adverse clinical outcomes such as mortality, major adverse events (MAEs), stroke, myocardial infarction, and repeated revascularization in patients with ITDM and NITDM after CABG have been searched from Medline, EMBASE, Cochrane, and PubMed databases. A short-term follow-up (≤30 days) and a long-term follow-up (≥1 year) were considered. Odds ratio (OR) with 95% confidence interval (CI) was used to express the pooled effect on discontinuous variables and the pooled analyses were performed with RevMan 5.3.Eleven studies involving a total of 64,152 patients with T2DM (23,781 patients with ITDM and 40,371 patients with NITDM) have been included in this meta-analysis. During the short-term follow-up period, patients with ITDM had a significantly higher mortality (OR: 1.47; 95% CI: 1.33-1.61, P < 0.00001) and MAEs (OR: 1.66; 95% CI: 1.48-1.87, P < 0.00001). During the long-term follow-up period, patients with ITDM still had a significantly higher rate of mortality, MAEs, and stroke (OR: 1.23, 95% CI: 1.02-1.49, P = 0.03; OR: 1.50, 95% CI: 1.07-2.12, P = 0.02; OR: 1.39, 95% CI: 1.22-1.59, P < 0.00001, respectively) after CABG. However, our results showed similar repeated revascularization rate between the ITDM and NITDM groups after CABG (OR: 1.31, 95% CI: 0.81-2.12, P = 0.27).According to this study, patients with ITDM had a significantly higher rate of mortality and MAEs compared with patients with NITDM after CABG. Stroke was also significantly higher in patients with ITDM during a long-term follow-up period. However, since the result for the long-term mortality had a higher heterogeneity as compared with the other subgroups, and because a similar revascularization rate was observed between the ITDM and NITDM groups after CABG maybe because of a limited number of patients analyzed, further studies still need to be conducted to completely solve this issue.