Coronary artery bypass grafting: Factors affecting outcomes

Impact of specialized nursing outpatient case management on post-coronary artery bypass grafting patients

BACKGROUND

Some patients with coronary atherosclerotic heart disease experience major adverse cardiac events (MACE) and require readmission after Coronary Artery Bypass Grafting (CABG) surgery. This is often attributed to patients' unhealthy lifestyles and dietary habits, inadequate understanding of the disease, and poor disease management compliance. Thus, searching for more targeted nursing intervention models that can enhance patients' self-management abilities and reduce the risk of readmission after CABG surgery is significant.

AIM

To observe the impact of specialized nursing outpatient case management on patients after CABG surgery.

METHODS

A total of 103 patients who underwent CABG surgery in our hospital between April 2021 and April 2022 comprised the study sample. The patients were divided into two groups using an odd-even number grouping method. The control group received routine nursing care, while the case management group received specialized nursing outpatient case management. The differences in psychological status, adherence to medical treatment, self-care ability, knowledge mastery, quality of life scores, and the occurrence rate of MACE were compared between the two groups.

RESULTS

After the intervention, the case management group had lower scores on the self-rating depression scale and self-rating anxiety scale and lower MACE rate, as well as higher scores for adherence to a healthy diet, medication adherence, good lifestyle habits, regular exercise, and timely follow-up, higher scores on the Coronary Heart Disease Self-Management Scale, higher scores for managing adverse habits, symptoms, emotional cognition, emergency response, disease knowledge, general lifestyle, and treatment adherence, higher scores for understanding coronary heart disease, recognizing the importance of medication adherence, understanding self-care points after CABG surgery, and being aware of post-CABG precautions, higher scores for physical well-being, disease condition, general health, social-psychological well-being, and work-related aspects (P < 0.05).

CONCLUSION

Specialized nursing outpatient case management can enhance patient adherence to medical treatment, knowledge mastery, psychological well-being, and overall quality of life in patients after CABG surgery.

The Effect of Gender on Triple Heart Valve Surgery Outcomes; Reinforcing Women's Health

Female gender is a risk factor in several cardiac surgery risk stratification systems. This study explored the differences in the outcomes following triple heart valve surgery in men vs women. The study included 250 patients (males n = 101; females n = 149) who underwent triple valve surgery from 2009 to 2020. BMI (body mass index) was higher in females (29.6 vs 26.5 kg/m2, P < .001), and diabetes was more common in males (44 vs 42%, P = .012). The ejection fraction was higher in females (55 vs 50%, P < .001). The severity of mitral valve stenosis and tricuspid valve regurgitation was significantly greater in females (33.11 vs 27.72%, P = .003 and 44.30 vs 19.8%, P < .001, respectively). Mitral valve replacement was more common in females (P < .001), and they had lower concomitant coronary artery bypass grafting (P = .001). Bleeding and renal failure were lower in females (P = .021 and <0.001, respectively). Hospital mortality, readmission, and reintervention were not significantly different between genders. By multivariable analysis, male gender was a risk factor for lower survival [HR (hazard ratio): 2.18; P = .024]. Triple valve surgery can be performed safely in both genders, with better long-term survival in females. Female gender was not a risk factor in patients undergoing triple valve surgery.

TIMP-1 in the prognosis of patients who underwent coronary artery bypass surgery: a 12-year follow-up study

Introduction

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been linked to clinical outcomes in patients with coronary artery disease (CAD). However, the prognostic value of TIMP-1 in patients with CAD who underwent coronary artery bypass grafting (CABG) has not been elucidated. We aimed to investigate the correlations of TIMP-1 with high-sensitivity C-reactive protein (hs-CRP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in the long-term prognosis of consecutive patients who underwent CABG.

Methods

A total of 234 patients (age: 70.4 ± 10.5 years, 84.6% men) with CAD who underwent CABG were prospectively enrolled. Preoperative levels of MMPs, TIMP-1, hs-CRP, and NT-proBNP were recorded. Major adverse cardiovascular events (MACE) were defined as non-fatal myocardial infarction, non-fatal stroke, and cardiovascular death.

Results

During a median follow-up of 12.1 years, 120 deaths were recorded. The deceased were older, had more manifest acute coronary syndrome (ACS), a lower left ventricular ejection fraction (LVEF), and an estimated glomerular filtration rate (eGFR), but significantly higher MMP13, TIMP-1, hs-CRP, and NT-proBNP compared with the survivors. After adjusting for age, sex, manifest ACS, eGFR, LVEF, total cholesterol, and triglycerides, TIMP-1 (hazard ratio and 95% confidence intervals per SD: 1.506, 1.183-1.917), hs-CRP (1.349, 1.183-1.561), and NT-ProBNP (1.707, 1.326-2.199) were all independently associated with all-cause mortality. The mediation analysis revealed that the mortality risks of TIMP-1 were partially mediated by NT-proBNP (62.2%) and hs-CRP (25.3%). The associations of TIMP-1 with MACE were partially mediated by NT-proBNP (54.4%) but not hs-CRP.

Conclusions

TIMP-1 was an independent predictor of long-term outcomes after CABG, with possible roles in subclinical inflammation and postoperative cardiac remodeling.

Sex-specific disparities in patients undergoing isolated CABG

Study objective

Examine sex-specific characteristics in patients undergoing coronary artery bypass grafting (CABG) at our institution.

Design

Retrospective chart review was performed utilizing our institutional Society of Thoracic Surgeons (STS) database.

Setting

An academic, quaternary care center from 2010 to 2021.

Participants

3163 females and 9573 males underwent isolated CABG.

Interventions

The institutional STS database was queried for preoperative, intraoperative, and postoperative variables.

Main outcome measures

Univariate comparisons between female and male groups were performed using chi-squared tests or fisher exact tests. Multivariate logistic regression was used to assess risk factors for 30-day mortality.

Results

Females had more preoperative comorbidities than males, including hypertension, diabetes, peripheral arterial disease, cerebrovascular disease, renal failure, and prior myocardial infarction. Females more frequently underwent urgent (61 % vs. 58 %) or emergent CABG (5.8 % vs. 4.3 %) compared to males (p < 0.0001). Females experienced longer total intensive care unit (ICU) hours (48.3 h vs. 43.5 h) (p < 0.0001), were more frequently discharged to an extended care facility (13 % vs. 6.4 %) (p < 0.0001) and prescribed less aspirin and beta blocker therapy at discharge than males. In-hospital mortality was higher in females (1.9 % vs. 1.2 %, p = 0.002), as was 30-day mortality (2.7 % vs. 1.6 %, p = 0.0001). Female sex was an independent risk factor for 30-day mortality (odds ratio = 1.46, 95 % CI: 1.06, 2.03, p = 0.02).

Conclusion

Over the past decade, females undergoing CABG had more preoperative comorbidities, urgent and emergent operations, longer postoperative ICU stay and a higher risk of mortality than their male counterparts. Further studies must investigate these disparities to improve outcomes for females undergoing CABG.

Activated Partial Thromboplastin Time and Mortality in Coronary Artery Bypass Grafting Patients

Background. To evaluate the prognostic value of preoperative activated partial thromboplastin time (APTT) in patients who underwent coronary artery bypass grafting (CABG). Methods. All data were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. The study population was divided to two groups according to the optimal cut-off value of APTT calculated by X-tile software, and Cox proportional hazard model was used to define independent effect of APTT on 4-year mortality. Survival curves were estimated by the Kaplan-Meier method, and the area under the receiver-operating characteristic curve (AUC) was calculated to compare APTT with other severity scores. Propensity score matching (PSM) analysis were applied to ensure the robustness of this study. Results. A total of 2,706 patients were included. The optimal cut-off value of APTT for 4-year mortality was 44 seconds. The Cox proportional hazard model showed that patients with $\text{APTT}\ge 44$ had a significantly higher risk of all-cause death than those with $\text{APTT}<44$ both before (HR (95% CI), 1.42 (1.16-1.74), $P<0.001$ ) and after PSM (HR (95% CI), 1.47 (1.14-1.89), $P=0.003$ ). The survival curves showed that patients with longer APTT had a significantly lower 1-year and 4-year cumulative survival probability. The ROC of APTT combined with other severity scores significantly increased predictive ability for 1-year and 4-year mortality. Conclusions. A longer APTT (≥44) was associated with a higher risk of mortality and can serve as a prognostic predictor in CABG patients.

Vasoactive inotropic score as a predictor of long-term mortality in patients after off-pump coronary artery bypass grafting

Increased vasoactive-inotropic score (VIS) is a reliable predictor of mortality and morbidity after cardiac surgery. Here, we retrospectively evaluated the association between VIS and adverse outcomes in adult patients after off-pump coronary artery bypass grafting (OPCAB). We included 2149 patients who underwent OPCAB. The maximal VIS was calculated for the initial 48 postoperative hours using standard formulae. The primary outcome was 1-year death. The composite adverse outcome was death, resuscitation or mechanical support, myocardial infarction, revascularization, new-onset atrial fibrillation, infection requiring antibacterial therapy, acute kidney injury, and stroke. Path-analysis was conducted using lactate and prognostic nutritional index (PNI). VIS was associated with 1-year death (odds ratio [OR] 1.07 [1.04–1.10], p < 0.001) and 1-year composite outcome (OR 1.02 [1.0–1.03], p = 0.008). In path-analysis, high VIS showed a direct effect on the increased risk of 1-year death and composite outcome. In the pathway using lactate as a mediating variable, VIS showed an indirect effect on the composite outcome but no significant effect on death. Low PNI directly affected the increased risk of 1-year death and composite outcome, and had an indirect effect on both outcomes, even when VIS was used as a mediating variable. In patients undergoing OPCAB, high VIS independently predicted morbidity and 1-year death. Patients with increased lactate levels following high VIS had an increased risk of postoperative complications, although not necessarily resulting in death. However, patients with poor preoperative nutritional status had an increased risk of unfavourable outcomes, including death, implying the importance of preoperative nutritional support.

Infrared Thermographic Imaging of Chest Wall Perfusion in Patients Undergoing Coronary Artery Bypass Grafting

Coronary artery disease represents a leading cause of death worldwide, to which the coronary artery bypass graft (CABG) is the main method of treatment in advanced multiple vessel disease. The use of the internal mammary artery (IMA) as a graft insures an improved long-term survival, but impairment of chest wall perfusion often leads to surgical site infection and increased morbidity and mortality. Infrared thermography (IRT) has established itself in the past decades as a non-invasive diagnostic technique. The applications vary from veterinary to human medicine and from head to toe. In this study we used IRT in 42 patients receiving CABG to determine the changes in skin surface temperature preoperatively, two hours, 24 h and 6 days after surgery. The results showed a significant and independent drop of surface temperature 2 h after surgery on the whole surface of the chest wall, as well as a further reduction on the left side after harvesting the IMA. The temperature returned to normal after 24 h and remained so after 6 days. The study has shown that IRT is sufficiently sensitive to demonstrate the known, subtle reduction in chest wall perfusion associated with IMA harvesting.

Simultaneous coronary artery disease and achalasia surgery: A novel approach

A 69-year-old female patient presented to cardiac surgery department with unstable angina due to severe coronary artery disease. Coronary artery bypass grafting was indicated; however, the patient's symptoms of achalasia, previously treated by the pneumatic dilatation, exacerbated. Subsequently, the patient underwent simultaneous surgery. After sternotomy, on cardiopulmonary bypass, esophagus was exposed and Heller myotomy was performed. Following cardioplegia, coronary artery bypass grafting was completed. The postoperative course was uneventful, and the patient was discharged on postoperative Day 9. In conclusion, this novel surgical technique can be effectively used in such cases.

Comparative study of coronary artery bypass graft materials: reduced contraction and ADMA levels in internal mammary artery versus saphenous vein

BACKGROUND

Vasospasm and atherosclerosis due to low endothelial capacity are the most important causes of coronary artery bypass graft failure observed in internal mammary artery (IMA) and saphenous vein (SV). Vasospasm can be mimicked in in vitro studies by inducing vasoconstriction of graft materials. In the present study, we aimed to compare the vascular contraction induced by several spasmogens including prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2α), phenylephrine (PE), leukotriene C4 (LTC4), LTD4, potassium chloride (KCl), and arachidonic acid between IMA and SV preparations. Furthermore, endothelial capacity, nitrite and asymmetric dimethylarginine (ADMA) levels were compared between two grafts.

METHODS

By using organ bath, contractile responses induced by different spasmogens were compared between IMA and SV preparations derived from patients underwent coronary artery bypass surgery (n=35). The endothelial capacity was determined by acetylcholine (ACh) -induced relaxation in PE-precontracted vessels. Nitrite and ADMA levels were measured in organ culture supernatant of IMA and SV preparations.

RESULTS

Contractile responses induced by PGE2, PGF2α, PE, LTC4, LTD4, KCl and arachidonic acid were significantly lower in IMA preparations versus SV preparations. ACh-induced relaxation was significantly more prominent in IMA than SV preparations. Nitrite levels were greater and ADMA levels were lower in IMA versus SV preparations.

CONCLUSIONS

IMA has reduced capacity to constrict to several vasoconstrictor agents. Furthermore, IMA has greater endothelial capacity associated with higher nitrite levels and lower ADMA levels. Our results support the greater patency rate observed in IMA versus SV preparations.

Does Age Affect the Short- and Long-Term Outcomes of Coronary Bypass Grafting?

The etiology of coronary artery disease (CAD) is multifactorial, stemming from both modifiable and nonmodifiable risk factors such as age. Several studies have reported the effects of age on various outcomes of coronary artery bypass grafting (CABG). This article reviews age-related outcomes of CABG and offers direction for further studies in the field to create comprehensive, evidence-based guidelines for the treatment of CAD. Ninety-two primary sources were analyzed for relevance to the subject matter, of which 17 were selected for further analysis: 14 retrospective cohort studies, 2 randomized clinical trials, and 1 meta-analysis. Our review revealed four broad age ranges into which patients can be grouped: those with CAD (1) below the age of 40 years, (2) between the ages of 40 and 60 years, (3) between the ages of 60 and 80 years, and (4) at or above 80 years. Patients below the age of 40 years fare best overall with total arterial revascularization (TAR). Patients between the ages of 40 and 60 years also fare well with the use of multiarterial grafts (MAGs) whereas either MAGs or single-arterial grafts may be of significant benefit to patients at or above the age of 60 years, with younger and diabetic patients benefitting the most. Arterial grafting is superior to vein grafting until the age of 80 years, at which point there is promising evidence supporting the continued use of the saphenous vein as the favored graft substrate. Age is a factor affecting the outcomes of CABG but should not serve as a barrier to offering patients CABG at any age from either a cost or a health perspective. Operative intervention starts to show significant mortality consequences at the age of 80 years, but the increased risk is countered by maintenance or improvement to patients' quality of life.

Risk factors for in-hospital mortality after coronary artery bypass grafting in Colombia

BACKGROUND

To determine the factors associated with in-hospital mortality after a coronary artery bypass (CABG) in a high-complexity clinic in the city of Santiago de Cali.

METHODS

A retrospective case-control analytical study was performed. Cases were defined as adult patients that had undergone CABG and died within 30 days of the surgery. Patients aged ≥18 years that had undergone isolated surgeries, i.e. procedures without other interventions combined, were included. This study excluded patients that had missing data in their medical records, had previously been in a state of coma, or had previously undergone cardiac surgery other than a bypass procedure. Exposure variables were measured at three stages: preoperative, intraoperative, and postoperative.

RESULTS

The study included 77 cases and 308 controls. The most common cause of death was cardiogenic shock (53.2%), followed by sepsis (27.3%). The multinomial logistic regression model revealed an association of in-hospital mortality with preoperative variables of age >75 years (odds ratio [OR] 2.5, 95% confidence interval [CI95%]: 1.1-5.8, p = 0.032), low socioeconomic status (OR 2.3, CI95%: 1.1-5.2, p = 0.034), heart failure (HF) (OR 3.2, CI95%: 1.5-7.0, p = 0.002), unstable angina (OR 4.2, CI95%: 1.9-9.0, p = 0.000), acute myocardial infarction (AMI) ≤7 days (OR 3.9, CI95%: 1.1-13.7, p = 0.037), chronic kidney insufficiency (CKI) (OR 2.9, CI95%: 1.2-7.0, p = 0.018), peripheral vascular disease (PVD) (OR 2.8, CI95%: 1.2-6.8, p = 0.019), and urgent/emergent surgery (OR 8.2, CI95%: 2.0-34.5, p = 0.004). Of the intraoperative variables, the model showed an association between the use of inotropic agents (OR 2.8, CI95%: 1.3-6.4, p = 0.011) and cardiogenic shock (OR 50.6, CI95%: 7.5-339, p = 0.000).

CONCLUSIONS

This study identifies the factors during preoperative and intraoperative periods that are associated with in-hospital mortality in patients that have undergone CABG.

Mechanism of IL-6-related spontaneous atrial fibrillation after coronary artery grafting surgery: IL-6 knockout mouse study and human observation

Clinical observation and ex vivo studies have established a strong association between inflammation and postoperative atrial fibrillation (POAF). However, it is unclear whether the inflammatory phenotype is causally linked to this event or is an epiphenomenon, and it is not known which inflammatory meditators may increase susceptibility to POAF. The limitations of available animal models of spontaneous POAF (sPOAF) makes it difficult to select an experimental system. Here, we provide experimental and clinical evidence for mechanistic involvement of interleukin-6 (IL-6) in sPOAF.

PHASE I

We established a mouse model of cardiac surgery with nonpaced sPOAF. IL-6 knockout mice were protected from sPOAF compared with wild-type mice.

PHASE II

At 48 hours after surgery, the heart was separated into 6 regions and cultured. IL-6 was expressed in all regions, with highest abundance in the left atrium (LA). In PHASE III, we demonstrated that IL-6 in the LA elicited early profibrotic properties in atria via the pSTAT3/STAT3 signaling pathway and contributed to sPOAF.

PHASE IV

In a translational prospective clinical study, we demonstrated that humans with POAF had a higher IL-6 concentration in pericardial drainage (PD). This study provides preliminary evidence of a causal relationship between IL-6 and POAF in a novel nonpaced sPOAF mouse model. IL-6 is a crucial prerequisite for eliciting profibrotic properties in cardiac myocytes via the pSTAT3 pathway during the early postoperative period, leading to an increased susceptibility to POAF. Measuring IL-6 in PD could be a new noninvasive biomarker for the clinical prediction of POAF.