Left Atrial Strain to Predict Postoperative Atrial Fibrillation in Patients Undergoing Off-pump Coronary Artery Bypass Graft.

OBJECTIVE: Postoperative atrial fibrillation (POAF) is associated with increased morbidity, mortality, and length of hospital stay. The objective of this study was to assess the utility of left atrial strain (LAS) to predict POAF in patients undergoing off-pump coronary artery bypass grafting (OPCABG). DESIGN: Retrospective observational study. SETTING: Tertiary care hospital. PARTICIPANTS: 103 patients undergoing OPCABG. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: In addition to comprehensive transthoracic echocardiography, LAS was measured for reservoir (R), conduction (CD), and contraction (CT) components. POAF was defined as new electrocardiographic evidence of AF requiring treatment. Logistic regression was done to assess factors associated with POAF. The diagnostic accuracy of variables in predicting POAF was assessed by receiver operating characteristic analysis. POAF was documented in 24 (23.3%) patients. There was no difference in ejection fraction, average global longitudinal strain, or proportion of left ventricular diastolic dysfunction grades between patients with POAF and patients without POAF. All three components of LAS: LAS R (19.2 ± 4.7 v 23.5 ± 4.8, p < 0.001), LAS CD (8.9 ± 3.7 v 12.3 ± 4.8, p = 0.1), and LAS CT (10.3 ± 3.9 v 12.1 ± 4.1, p = 0.04), were significantly lower among patients with POAF compared with patients without POAF, respectively. According to univariate analysis, all components of LAS were statistically significant predictors of POAF. In multivariate analysis, only age (odds ratio = 1.08, p = 0.025) and LAS R (odds ratio = 0.84, p = 0.004) were independently associated with POAF. LAS R was a better predictor of POAF, with an area under the curve (AUC) of 0.758, than LAS CD (AUC = 0.67) and LAS CT (AUC = 0.62). LAS R had an optimal cutoff of 23% with sensitivity of 95.8% (confidence interval: 78.9-99.9%) and specificity of 49.4% (37.9-60.9%) to predict POAF. CONCLUSIONS: LAS R is a significant predictor of POAF, and its use can be recommended for screening of OPCABG patients at high risk of POAF.

Effect of Buteyko Breathing Technique as an Adjunct to Routine Physiotherapy on Pulmonary Functions in Patients Undergoing Off-pump Coronary Artery Bypass Surgery: A Randomized Controlled Trial.

Background: Coronary artery disease (CAD) poses a substantial and increasing public health concern in India, particularly among individuals aged 20 and above. The postoperative phase following coronary artery bypass graft (CABG) surgery presents potential complications, notably impacting the pulmonary system. Emerging evidence suggests that the Buteyko breathing technique not only improves lung function but also positively influences the psychological well-being of CABG patients. This study seeks to assess the impact of the Buteyko breathing technique on pulmonary functions in individuals who have undergone off-pump CABG. Materials and methods: In this randomized controlled trial, patients undergoing off-pump CABG were allocated to either the Buteyko breathing technique group (n = 35) or the control group (n = 35). The intervention group received supervised Buteyko breathing technique sessions twice daily for 15 minutes, concurrently with cardiac rehabilitation from postoperative day (POD-2 to POD-7). The control group underwent phase I cardiac rehabilitation. Outcome measures, including pulmonary function test (PFT), chest expansion, and breath-holding tests were evaluated at baseline (POD-2) and conclusion (POD-7). Results: Statistical analyses were conducted with a significance level set at p < 0.05. Both the control and intervention groups exhibited statistically significant improvements in pulmonary function, chest expansion at three levels, and breath-holding time (p = 0.0001). However, the Buteyko breathing group demonstrated a more significant improvement compared with the control group. Conclusion: The integration of the Buteyko breathing technique into conventional physiotherapy proves to be a beneficial strategy, leading to improvements in pulmonary function, breath-holding duration, and chest expansion for individuals who underwent off-pump CABG surgery. How to cite this article: Mavkar SS, Shukla MP. Effect of Buteyko Breathing Technique as an Adjunct to Routine Physiotherapy on Pulmonary Functions in Patients Undergoing Off-pump Coronary Artery Bypass Surgery: A Randomized Controlled Trial. Indian J Crit Care Med 2024;28(3):280-285.TRI Number: CTRI/2022/12/048295.

Midterm outcome of off-pump CABG for severe LV dysfunction-Does LV size and function predict their midterm outcome?

BACKGROUND: The superiority of surgical revascularization in ischemic cardiomyopathy is established beyond doubt, and off-pump CABG (OP-CABG) is a safe way of revascularization in this high-risk subset. Data on the effect of postoperative ventricular function and size on their midterm outcome is scarce. MATERIALS AND METHODS: A retrospective study was done on 211 consecutive patients with severe LV dysfunction who underwent OP-CABG from January 2017 to December 2018. Data were collected from the institutional database. Their operative and midterm outcomes were statistically analyzed. RESULTS: The mean age of the cohort was 58.4 ± 8.3 years. An average number of grafts was 3.1 ± 0.8 (cumulative intended number of grafts-3). Operative mortality was 10.9%. Preoperative NYHA class (p < .0001; OR, 19.72) and postoperative IABP insertion (p < .008; OR, 88.75) were independent predictors of operative mortality. The mean follow-up period was 3.14 ± 0.07 years, was 97.4% complete with cardiac mortality of 5.8%. Postoperative LVEF (p = .002; OR, 0.868) and LV dimensions (systole & diastole) (p = .013, OR = 1.182 and p = .036, OR = 1.184, respectively) were independent predictors of midterm mortality. Midterm major adverse cardiovascular event-free survival of operative survivors was 89%. There was no correlation between postoperative LV dimension and NYHA status(p > .05). Myocardial viability was not associated with early (p = .17) or midterm mortality (p = .676). CONCLUSION: OP-CABG can achieve complete revascularization in patients with severe LV dysfunction with good midterm outcomes, albeit with high early operative mortality. Postoperative change in LV dimension and EF are predictors of midterm mortality.

Off pump coronary artery bypass in patients with an ejection fraction of <20%. What is our strategy?

Patients with left ventricular dysfunction and low ejection fraction (EF) are at high risk of complication and mortality after coronary artery bypass grafting (CABG). The potential success of off-pump CABG in this high-risk population has yet to be illustrated. Herein, we present our experience in regards to surgical planning and strategy on how to perform off-pump CABG in patients with very low EF.

The expansion of no-touch harvesting sequential vein graft after off-pump coronary artery bypass grafting.

BACKGROUND AND AIM OF THE STUDY: Many studies support that the no-touch (NT) procedure can improve the patency rate of vein grafts. However, it is not clear that the sequential vein graft early expansion in the NT technique during off-pump coronary artery bypass grafting (CABG). This study will explore this issue. METHODS: This was a prospective single-center randomized controlled clinical trial. A total of 100 patients undergoing off-pump CABG with the sequential saphenous graft were randomly assigned to two groups: the NT and conventional (CON) groups. Perioperative and postoperative data were collected during the hospital stay. The mean diameter of sequential grafts was measured using cardiac computed tomography angiography 3 months after the operation. RESULTS: There was a significant difference in the average diameter of sequential grafts between the two groups (NT: [2.98 ± 0.42], CON: [3.26 ± 0.51], p = .005). There was no difference in occlusion of sequential venous grafts between the two groups (NT: 4/48 [8.3%], CON: 5/49 [10.2%], p = 1.000). There were differences in surgery time between the two groups (NT: 220 [188,240], CON: 190 [175,230], p = .009). CONCLUSIONS: The sequential graft early expansion in the NT technique is not as pronounced as that in the conventional technique, which may have a long-term protective effect on the grafts.

Acute myocardial infarction in a patient with active actinic rectitis bleeding: Between the sword and the wall.

A The coronary artery bypass graft (CABG) is common. Sometimes can be challenging. Here we present a 79-year-old man presented with unstable angina and simultaneous activelower gastrointestinal bleeding (hemoglobin level, 5.1 g/L) due to actinic rectitis after radiation therapy for prostate carcinoma performed 1 year previously. Coronary angiography showed marked stenosis of the left anterior descending artery. Antiplatelet aggregation therapy, such as percutaneous coronary intervention or systemic heparin therapy for coronary artery bypass, was not feasible owing to the active rectal bleeding. Therefore, off-pump CABG has performed without systemic heparin therapy and the patient recovered well. For specific cases, CABG without systemic heparin therapy can be safely performed.

Gullain-Barré syndrome following off-pump coronary artery bypass grafting.

We report a case of Gullain-Barré syndrome after off-pump coronary artery bypass grafting surgery in a diabetic male with idiopathic thrombocytopenic purpura who recovered fully after treatment with intravenous immunoglobulin without any residual weakness.

Early outcomes of on-pump versus off-pump coronary artery bypass grafting.

OBJECTIVES: To see the early post-operative outcomes of off-pump versus on-pump coronary artery bypass graft surgery. METHODS: This retrospective analytical study was conducted at Ch. Pervaiz Elahi Institute of Cardiology Multan, Pakistan. Our Primary outcome variables were; necessity of inotropic support, nonfatal myocardial infarction, ICU stay, nonfatal stroke, new renal failure requiring dialysis and death within 30 days after operation. There were two groups of patients; Group-I (On-pump group) and Group-II (Off-pump Group). SPSS V17 was used for data analysis. Independent sample t-test and Mann Whitney U test were used to compare quantitative Variables. Chi-square test and Fisher's exact test were used to analyze qualitative variables. P-value ≤ 0.05 was considered significant. RESULTS: Three hundred patients were included in this study. There were no significant difference regarding risk factors except hyper-cholestrolemia which was high in off pump group (p-value 0.05). Angiographic and Echocardiographic characteristics e.g. preoperative ejection fraction, LV function grade and severity of CAD was same between the groups. Mortality risk scores and Priority status for surgery were also same. Regarding post-operative outcomes; Post-op CKMB Levels, need and duration of inotropic support, mechanical ventilation time and ICU stay was significantly less in Off-Pump group (p-value 0.001, <0.0001, 0.006, 0.025 and 0.001 resp.). Peri-operative chest drainage was significantly high in On-pump CABG group (p-value 0.027). Incidence of post-op complications was not statistically different between the groups. CONCLUSIONS: At 30 days follow-up, Incidence of myocardial infarction, necessity and duration of inotropic support, ICU stay period and peri-operative bleeding were significantly less in off-pump group. The incidence of neurologic, pulmonary and renal complications was same between the off-pump and on-pump groups.

Off-pump Bilateral Internal Thoracic Artery Grafting.

BACKGROUND: The long-term benefit of bilateral internal thoracic grafts (BITA) is well established. BITA grafting is often avoided in diabetic, female, obese, elderly and other high-risk patients because of concerns for deep sternal wound infection. The objective of this study is to analyse early results of our BITA grafting and to establish the safety of BITA use in all patients. METHODS: All cases of isolated consecutive unselected CABG were included in this retrospective study. BITA were used in-situ - one was used to graft left anterior descending artery and the other was used as inflow for a composite graft with radial artery. Dual inflow using in situ BITA grafting allows easy bailout by using an additional vein graft. RESULTS: BITA was used in 574 patients out of 602 (95.35%). Incidence of early death was 1.33% (8/602), stroke 0.5% (3/602), reoperation for bleeding 0.17% (1/602). Deep sternal wound infection was not seen in any patient but nine patients (1.5%) had superficial wound infection which healed with dressing. CONCLUSION: We have used BITA in 95% of our unselected, consecutive off-pump CABG patients without any major wound complications. Our limited experience has shown off-pump CABG using BITA grafting can be safely adopted routinely with excellent early result.

Off-pump versus on-pump revascularization in females: a meta-analysis of observational studies.

BACKGROUND: Coronary revascularization in female patients presents several challenges, including smaller target vessels and smaller conduits. Furthermore, late presentation and more co-morbidities than males may increase complication rates. The aim of this study was to assess whether off-pump coronary artery bypass (OPCAB) improves outcomes when compared to on-pump coronary artery bypass (ONCAB) in the female population. METHODS: A systematic literature review identified six observational studies, incorporating 23313 patients (n=9596 OPCAB, 13717 ONCAB). These were meta-analyzed using random effects modeling. Heterogeneity, subgroup analysis, quality scoring and publication bias were assessed. The primary endpoints were 30-day mortality and major cardiac, respiratory and renal complications. Secondary endpoints were the number of grafts per patient. RESULTS: No statistically significant difference was observed in 30-day mortality between the OPCAB and ONCAB groups (4.8% vs. 0.7%; OR 0.96; 95% CI [0.41, 2.24], p=0.92). Significant inter-study heterogeneity was also present (I2=94%) and was not explained by study size or quality. Peri-operative myocardial infarction (OR 0.65; 95% CI [0.51, 0.84], p=0.0009) was significantly lower with OPCAB without significant heterogeneity; however, OPCAB did not significantly alter other morbidity outcomes. OPCAB was associated with a trend towards fewer grafts per patient than ONCAB. CONCLUSIONS: OPCAB is a safe alternative to ONCAB in the surgical revascularisation of female patients and may reduce post-operative myocardial infarction (MI). However, this does not translate into a reduction in 30-day mortality and OPCAB does not significantly improve other cardiovascular, renal or neurological outcomes. Late outcome data remains lacking and a well-structured, randomized trial is required to answer vital questions regarding the effect of OPCAB on women in the long-term.

Controversy. On pump or off pump: what will I do when I grow up? A narrative systematic review.

The transition from the second to the third millennium happened to be a turning point in the history of myocardial revascularization on a beating heart, which moved from technical development to critical evaluation. This article describes how the initial acceptance and spread of off-pump coronary artery bypass grafting (OPCABG) was followed by the general perception that the technique could not fulfill the expectations placed in it and provides some insight on what should we do with the know-how of OPCABG in the present and the future of coronary surgical revascularization.

Short-Term Clinical Results of Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) Procedure.

Objectives: Minimally invasive direct coronary artery bypass (MIDCAB) is an alternative for revascularisation of the isolated left anterior descending (LAD) artery or as a multi-vessel (MV) procedure for the diagonal branch (RD) or the left circumflex coronary artery (LCX) region. Methods: From 2021 to 2022, 91 patients underwent MIDCAB or multi-vessel MIDCAB procedures in our heart center. The left internal mammary artery (LIMA) was anastomosed to the left anterior descending artery via the left minithoracotomy approach in all patients. Results: Of the patients, a total of 86.8% were male. Eighty percent of the patients had two- or three-vessel coronary artery disease. The mean age was 65.1 ± 10.1 years. The mean operation time was 2.6 ± 0.8 h. The 30-day mortality was 0. The mean required packed red blood cells (pRBC) was 0.4 ± 1.2 unit. The mean intensive care unit stay (ICU) was 1.5 ± 1.6 days. The mean follow-up time was 1.5 ± 0.5 years. One patient received percutaneous coronary intervention due to de novo stenosis of the RCA. Late mortality was 2.2%. The Kaplan-Meier survival rate was 98.8% at 1 and 2 years. Conclusions: The postoperative complication rate of our MIDCAB cohort is low, and the short-term survival is favorable. Our postoperative and short-term clinical results demonstrate that this procedure is safe and feasible.

Hybrid robotic-assisted coronary revascularization and transcatheter aortic valve replacement: a single-center experience.

OBJECTIVES: The efficacy of hybrid robotic-assisted coronary artery bypass grafting (CABG) and transcatheter aortic valve replacement (TAVR) for coronary and aortic valve disease is poorly reported. Herein, we report our experience with this hybrid approach. METHODS: Between January 2018 and June 2022, 10 (7 male, 3 female) patients with a mean age of 81 years underwent the hybrid procedure. Coronary revascularization was performed prior to TAVR with robotic-assisted left internal mammary artery-to-left anterior descending (LAD) bypass grafting for left main or proximal LAD lesions with or without multivessel disease with or without hybrid percutaneous coronary intervention (PCI). RESULTS: Five patients had left main disease, and 5 had proximal LAD disease with or without multivessel disease. All patients tolerated the robotic-assisted CABG procedure well; 9 patients were extubated in the operating room and all patients were ambulatory on postoperative day 1. Five patients underwent hybrid PCI for non-LAD lesions. TAVR was subsequently performed at intervals ranging from 3 days to 5 months after CABG. One patient with end-stage renal disease on hemodialysis required hospitalization for heart failure during the interval period. The 1-year mortality rate was 0%, and 3 patients died during late follow-up (24-43 months). CONCLUSIONS: This innovative, less invasive approach demonstrates the potential for early recovery in appropriately selected patients with complex coronary and aortic valve disease with promising mid-term outcomes.

Role of magnesium alone or in combination with diltiazem and/or amiodarone in prevention of atrial fibrillation following off-pump coronary artery bypass grafting.

Objectives: In this study the authors have tried to examine the role of magnesium alone or in combination with diltiazem and / or amiodarone in prevention of atrial fibrillation (AF) following off-pump coronary artery bypass grafting (CABG). Background: AF after CABG is common and contributes to morbidity and mortality. Various pharmacological preventive measures including magnesium, amiodarone, diltiazem, and combination therapy among others have been tried to lower the incidence of AF. Most of the studies have been performed in patients undergoing conventional on-pump CABG. In this uncontrolled trial, efficacy of magnesium alone or in combination with amiodarone and / or diltiazem has been studied in patients undergoing off-pump CABG. Methods: One hundred and fifty patients undergoing off-pump CABG were divided into 3 groups, Group M (n=21) received intraoperative magnesium infusion at 30mg/ kg over 1 hour after midline sternotomy; Group MD (n=78) received magnesium infusion in similar manner with diltiazem infusion at 0.05 µg/kg/hr throughout the intraoperative period; Group AMD (n=51) received preoperative oral amiodarone at a dose of 200 mg three times a day for 3 days followed by 200 mg twice daily for another 3 days followed by 200 mg once daily till the day of surgery along with magnesium and diltiazem infusion as in other groups. AF lasting more than 10 min or requiring medical intervention was considered as AF. Results: The overall incidence of postoperative AF was 12.6% with 11.7% in group AMD, 19% in group M, and 11.5% in group MD, which was not statistically significant. Conclusions: It is concluded that the use of amiodarone and/or diltiazem in addition to magnesium did not result in additional benefit of lowering the incidence of AF.

Severe Refractory Vasoplegic Shock Syndrome after OPCABG Successfully Treated with Hydroxycobalamin: A Case Report and Review of the Literature.

BACKGROUND: Vasoplegic shock syndrome (VSS) after an off-pump coronary artery bypass graft (OPCABG) is an extremely rare condition. Inotropic support is usually the first-line therapy, though it can precipitate several complications or be ineffective. We report the first case of severe refractory VSS after OPCABG successfully treated with hydroxycobalamin. METHODS: A 77-year-old gentleman underwent OPCABG for three vessels coronary artery disease. Preoperative LV ejection fraction was 28%, and the patient before surgery started sacubitril/valsartan titrated, then, at the highest dose. Surgery was uneventful and, by the end of the procedure, TEE showed improved biventricular contractility. RESULTS: The patient was transferred to the ICU without inotropic support, but soon developed hypotension. TEE ruled out pericardial tamponade and confirmed fair contractility. Norepinephrine was titrated to a medium-high dose, vasopressin was started and a Swan-Ganz catheter was placed. SVR was 480 dyn·s·cm-5. Despite aggressive pharmacologic treatment (including methylprednisolone and methylene blue), no improvements were noticed. Ten grams of hydroxycobalamin were administered. One hour later, hemodynamic status re-assessment showed SVR > 800 dyn·s·cm-5. Afterward, vasopressors were gradually reduced. CONCLUSIONS: Our case demonstrated the importance of adequate early treatment in VSS after OPCABG. This case report shows, for the first time, that hydroxycobalamin was effectively used to restore homeostasis.

CABG Patients Develop Global DNA Hypermethylation, That Negatively Affect the Mitochondrial Function and Promote Post-Surgical Cognitive Decline: A Proof of Concept in Small Cohort.

Global DNA hypermethylation and mitochondrial dysfunction are reported to be associated with the development of mild cognitive decline (MCI). The present study aims to generate preliminary data that connect the above association with post-surgical coronary artery bypass grafting (CABG) cognitive decline in patients. Data were collected from 70 CABG patients and 25 age-matched controls. Cognitive function was assessed using the Montreal Cognitive Assessment (MOCA) test on day 1 (before surgery) and on the day of discharge. Similarly, blood was collected before and one day after the CABG procedure for mitochondrial functional analysis and expression of DNA methylation genes. Test analysis score suggested 31 (44%) patients had MCI before discharge. These patients showed a significant decrease in complex I activity and an increase in malondialdehyde levels (p < 0.001) from the control blood samples. Post-surgical samples showed a significant reduction in blood MT-ND1 mRNA expression from control and from pre-surgical samples (p < 0.005), along with elevated DNMT1 gene expression (p < 0.047), with an insignificant increase in TET1 and TET3 gene expression. Correlation analysis showed a significant positive relation between cognitive decline and elevated blood DNMT1 and declined blood complex I activity, signifying that cognitive decline experienced by post-surgical CABG patients is associated with increased DNMT1 expression and declined complex I activity. Based on the data, we conclude that both DNA hypermethylation and mitochondrial dysfunction are associated with post-CABG MCI, where the former is negatively correlated, and the latter is positively correlated with post-surgical MCI in CABG cases. Additionally, a multimarker approach that comprises MOCA, DNA methylation, DNMT, and NQR activities can be utilized to stratify the population that is sensitive to developing post-CABG MCI.

Assessing the Patient Outcomes and Performance of a Cardiothoracic and Vascular Surgery (CTVS) Unit During Its First Two Years in a Tier-2 City in India: A Comprehensive Audit and Analysis.

This detailed article presents a comprehensive overview of the initial two-year experience in establishing a new cardiothoracic vascular surgery (CTVS) facility in a tier-2 city in India. The article discusses various aspects of setting up and operating a specialized healthcare facility. The first two years of developing the CTVS facility were included in the study period. The manpower included one cardiothoracic vascular surgeon, one cardiac anesthesiologist, two perfusionists, and two physician assistants, along with four other ancillary staff to assist in the smooth functioning of the operation theater. The CTVS recovery staff included 15 nursing officers. There was only one modular operation theater reserved for cardiothoracic vascular surgeries, along with a five-bed recovery room (CTVS intensive care unit). One-hundred-seventy-two procedures were done, including 122 open heart surgeries, 36 vascular procedures, and 14 thoracic procedures. The majority of patients were discharged by the seventh day postoperatively. Overall complication and mortality rates were 8% and 4.6%, respectively. This article also discusses relevant hospital policy, challenges faced, and future recommendations for similar endeavors. The findings highlight the successful implementation of the facility and its impact on providing specialized cardiac care to the local population.

Clinical outcomes of off-pump coronary artery bypass graft in patients with diabetes and non-diabetics: A systematic review and meta-analysis.

BACKGROUND AND AIM: Diabetes mellitus is a prevalent risk factor for developing coronary artery disease which worsens the clinical outcomes of patients undergoing coronary artery bypass grafting (CABG). This study aimed to determine the clinical outcomes of patients with diabetes and non-diabetic patients who underwent off-pump CABG surgery. METHOD: Medline, Scopus, Proquest, Embase, Web of Science, and Google scholar were searched until September 10, 2021. The effect sizes including unstandardized mean difference and odds ratio with 95% confidence interval were calculated using "Metan" package. The Cochran's Q-test and I2 statistic were used to assess heterogeneity, a random-effects model was applied to estimate the pooled effect sizes, and meta-regression was used to investigate the factors affecting heterogeneity between studies. RESULTS: 10 studies with 6200 sample sizes were included in the study. In groups with diabetes, Summary odds ratio (SOR) and 95% confidence interval of infection was 2.18 more than non-diabetic groups. Also, odds renal complication was 1.74 more than non-diabetic groups, and the odds cardiovascular complication in groups with diabetes was 1.30 more than non-diabetics. There were no differences in mortality, neurologic, respiratory and surgical complications between groups with diabetes and non-diabetics. Based on meta-regression results, age (Coefficient: 0.942; p = 0.009) had a significant direct relationship and sample size (Coefficient: 0.001; p = 0.009) had an indirect significant relationship with heterogeneity of neurologic outcomes. There was no significant publication bias in our results. CONCLUSION: Our study revealed that off-pump CABG led to some significant outcomes in patients with diabetes compared to non-diabetics. Renal and infection complications were higher in patients with diabetes but no significant differences were seen in most of other postoperative outcomes between the two groups.