Management of early postoperative coronary artery bypass graft failure

Evaluation of the Patients with Recurrent Angina After Coronary Artery Bypass Grafting

INTRODUCTION

In this study, we aimed to evaluate the most common causes of recurrent angina after coronary artery bypass grafting (CABG) and our treatment approaches applied in these patients.

METHODS

We included all patients who underwent CABG, with or without percutaneous coronary intervention after CABG, at our hospital from September 2013 to December 2019. Patients were divided into two groups according to the time of onset of anginal pain after CABG. Forty-five patients (58.16 ± 8.78 years) had recurrent angina in the first postoperative year after CABG and were specified as group I (early recurrence). Group II (late recurrence) comprised 82 patients (58.05 ± 8.95 years) with angina after the first year of CABG.

RESULTS

The mean preoperative left ventricular ejection fraction was 53.22 ± 8.87% in group I, and 54.7 ± 8.58% in group II (P=0.38). No significant difference was registered between groups I and II regarding preoperative angiographic findings (P>0.05). Failed grafts were found in 27.7% (n=28/101) of the grafts in group I as compared to 26.8% (n=51/190) in group II (P>0.05). Twenty-four (53.3%) patients were treated medically in group I, compared with 54 (65.8%) patients in group II (P=0.098). There was a need for intervention in 46.6% (n=21) of group I patients, and in 34.1% (n=28) of group II patients.

CONCLUSION

Recurrent angina is a complaint that should not be neglected because most of the patients with recurrent angina are diagnosed with either native coronary or graft pathology in coronary angiography performed.

[Comparative analysis of in-hospital and long-term results of patients with acute dysfunction of coronary bypass grafts depending on treatment tactics]

OBJECTIVE

Comparative analysis of in-hospital and long-term mortality of patients in whom acute dysfunction of coronary bypass grafts was detected in the early postoperative period depending on conservative or surgical tactics.

MATERIAL AND METHODS

The study is a retrospective analysis of data from 8801 patients who underwent elective coronary artery bypass grafting (CABG) between 2011 and 2022 at the Federal Center for Cardiovascular Surgery (Russia, Chelyabinsk). Among them, 196 patients underwent emergency coronary artery bypass grafting due to suspected perioperative myocardial infarction in the early postoperative period. In 119 patients, dysfunction of coronary bypass grafts was detected, in 77 patients no pathological changes were found. The criteria for inclusion in the study were patients with dysfunction of coronary bypass grafts (n=119). The 1st group included patients who underwent conservative therapy (n=33), the 2nd group (n=86) included those who underwent repeated myocardial revascularization. The primary endpoint was hospital mortality, secondary endpoints were long-term mortality and adverse cardiovascular events (myocardial infarction, stroke, repeat myocardial revascularization). Patients were surveyed via telephone.

RESULTS

In-hospital mortality in the group of surgical reintervention was 8.1%, in the group of conservative treatment - 9.1% (p=0.867). According to the results of multivariate analysis, predictors of hospital mortality in patients of both groups were extracorporeal membrane oxygenation (p=0.014), time of artificial circulation (p=0.031), duration of artificial ventilation (p=0.001), number of days in intensive care (p<0.001). When analyzing long-term mortality using the Kaplan-Meier method in group 1 and group 2, no statistically significant differences were found; in the group of conservative therapy - 85±9.6 [66.2-103.7] months versus 108.2±4.8 [98.8-117.6] months in the surgery group (log-rank p=0.06). When analyzing long-term mortality from cardiovascular causes and the occurrence of adverse cardiovascular events, statistically significant differences were determined: in the group of conservative therapy - 92.5±9.3 [74.2-110.7] months versus 117.8±3.3 [111.2-124.3] months in the surgical treatment group (log-rank p=0.007) and 78.1±9.2 [60-96.3] months versus 98.9±3.9 [91.3-106.5] months (log-rank p=0.008), respectively.

CONCLUSION

In-hospital mortality was comparable between groups. Long-term mortality from cardiovascular causes and the number of adverse cardiovascular events were significantly higher in the conservative therapy group. With timely detection of acute dysfunction of coronary bypass grafts, an active surgical approach has an advantage over conservative tactics and can improve the long-term prognosis of patients.

Healthcare costs and outcomes associated with surgical site infections after coronary artery bypass grafting surgeries in Oman

BACKGROUND

Surgical site infection (SSI) after coronary artery bypass graft (CABG) surgeries is considered a key indicator of the quality of healthcare services.

OBJECTIVE

This study aimed to estimate the healthcare outcomes associated with SSIs after CABG surgeries in Oman in terms of mortality rate, case-fatality rate, LOS, readmission rate and healthcare costs.

METHODS

The nested case-control study design was used based on retrospective data, which was conducted from 2016 to 2017. The case group encompassed all CABG patients with confirmed SSIs within 30 days of the surgery (n = 104) while controls were CABG patients without SSIs (n = 404).

RESULTS

Forty-four (42.3%) of the SSI patients were readmitted to the hospital compared to eight (2%) of the control group (p < .001). Patients in the case group had a longer LOS (M = 24.4, SD = 44.6 days) compared to those in the control group (M = 11, SD = 21 days, p = .003). The mean healthcare costs of cases (M = Omani Rial [OMR] 3823, SD = OMR 2516) were significantly greater than controls (M = OMR 3154, SD = OMR 1415, p = .010).

CONCLUSION

Results from this study can be baseline data for formulating new hypotheses and testing the causal relationship between SSIs after CABG surgeries and the readmission rate, LOS and health care costs.Key messagesSurgical Site Infections (SSIs) are still a major complication after cardiac surgeries in Oman.SSIs after cardiac surgeries are associated with substantially increased healthcare costs and length of stay.SSIs after cardiac surgeries are associated with negative outcomes such as mortality and case-fatality rates.

Considerations on the Management of Acute Postoperative Ischemia After Cardiac Surgery: A Scientific Statement From the American Heart Association

Acute postoperative myocardial ischemia (PMI) after cardiac surgery is an infrequent event that can evolve rapidly and become a potentially life-threatening complication. Multiple factors are associated with acute PMI after cardiac surgery and may vary by the type of surgical procedure performed. Although the criteria defining nonprocedural myocardial ischemia are well established, there are no universally accepted criteria for the diagnosis of acute PMI. In addition, current evidence on the management of acute PMI after cardiac surgery is sparse and generally of low methodological quality. Once acute PMI is suspected, prompt diagnosis and treatment are imperative, and options range from conservative strategies to percutaneous coronary intervention and redo coronary artery bypass grafting. In this document, a multidisciplinary group including experts in cardiac surgery, cardiology, anesthesiology, and postoperative care summarizes the existing evidence on diagnosis and treatment of acute PMI and provides clinical guidance.

Ninety-day all-cause emergency room use among coronary artery bypass grafting patients associated with near-infrared fluorescence imaging: a retrospective cohort study

Reducing emergency room (ER) use may indicate the improved quality of patient care at index hospitalization. The aim of this study is to determine whether the use of near-infrared fluorescence (NIRF) imaging with indocyanine green (ICG) during coronary artery bypass grafting (CABG) surgery is associated with a lowered 90-day all-cause ER use.

Materials and Methods

This retrospective cohort study included adult patients with inpatient hospitalizations between January 2016 and June 2020 for an isolated CABG procedure at a US hospital. Propensity score matching was used to create matched cohorts to address the differences in patient, payer type, hospital, and clinical characteristics. A multivariable regression analysis was conducted to determine the association of NIRF imaging with ICG on ER use within 90 days of discharge after controlling for patient, payer type, hospital, and clinical covariates.

Results

In total, 230 506 adult patients underwent an isolated CABG procedure. Less than 1% (n=1965) were assessed with NIRF imaging using ICG. There were differences in patient demographic and hospital characteristics between the treatment group (i.e. NIRF with ICG) and the comparison group (i.e. no NIRF with ICG). After controlling for covariates, a statistically significant lower 90-day all-cause ER use was documented among the treatment group (adjusted odds ratio=0.84, 95% confidence interval=0.73-0.96, P<0.009). Reasons associated with ER use were similar between the two groups.

Conclusion

Routine intraoperative graft patency assessment with NIRF imaging using ICG may help to improve a patient's care experience and reduce subsequent resource utilization. Intraoperative graft patency assessment with NIRF imaging using ICG is associated with a 90-day all-cause ER use reduction among CABG patients. Further studies are needed to compare the ER usage among centers that used this technique versus those that did not to determine if associated reductions in ER use are a center or technique-specific phenomenon.

Contemporary coronary artery bypass graft surgery and subsequent percutaneous revascularization

Patients who have undergone coronary artery bypass graft (CABG) surgery are susceptible to bypass graft failure and progression of native coronary artery disease. Although the saphenous vein graft (SVG) was traditionally the most-used conduit, arterial grafts (including the left and right internal thoracic arteries and the radial artery) have improved patency rates. However, the need for secondary revascularization remains common, and percutaneous coronary intervention (PCI) has become the most common modality of secondary revascularization after CABG surgery. Procedural characteristics and clinical outcomes differ considerably from those associated with PCI in patients without previous CABG surgery, owing to altered coronary anatomy and differences in conduit pathophysiology. In particular, SVG PCI carries an increased risk of complications, and operators are shifting their focus towards embolic protection strategies and complex native-vessel interventions, increasingly using SVGs as conduits to facilitate native-vessel PCI rather than pursuing SVG PCI. In this Review, we discuss the differences in conduit pathophysiology, changes in CABG surgery techniques, and the latest evidence in terms of PCI in patients with previous CABG surgery, with a particular emphasis on safety and long-term efficacy. We explore the subject of contemporary CABG surgery and subsequent percutaneous revascularization in this complex patient population.

Translational model of vein graft failure following coronary artery bypass graft in atherosclerotic microswine

OBJECTIVE

Vein graft failure is a major complication following coronary artery bypass graft surgery. There is no translational model to understand the molecular mechanisms underlying vein-graft failure. We established a clinically relevant bypass graft model to investigate the underlying pathophysiological mechanisms of vein-graft failure and identify molecular targets for novel therapies.

METHODS

Six female Yucatan microswine fed with high cholesterol diet underwent off-pump bypass, using superficial epigastric vein graft, which was anastomosed to an internal mammary artery and distal left anterior descending artery. Vein-graft patency was examined 10-months after bypass surgery by echocardiography, coronary angiography, and optical coherence tomography followed by euthanasia. Coronary tissues were collected for histomorphometry studies.

RESULTS

Atherosclerotic microswine were highly susceptible to sudden ventricular fibrillation with any cardiac intervention. Two out of six animals died during surgery due to ventricular fibrillation. Selection of the anesthetics and titration of their doses with careful use of inotropic drugs were the key to successful swine cardiac anesthesia. The hypotensive effects of amiodarone and the incidence of arrhythmia were avoided by the administration of magnesium sulfate. The vein-graft control tissue displayed intact endothelium with well-organized medial layer. The grafted vessels revealed complete occlusion and were covered with fibrous tissues. Expression of CD31 in the graft was irregular as the layers were not clearly defined due to fibrosis.

CONCLUSION

This model represents the clinical vein-graft failure and offers a novel platform to investigate the underlying molecular mechanisms of vein-graft disease and investigate novel therapeutic approaches to prevent its progression.

Heart team 2.0: A decision tree for minimally invasive and hybrid myocardial revascularization

Recent years have seen an important shift in the target population for myocardial revascularization. Patients are increasingly presenting with more complex coronary artery disease (CAD), but also with multiple comorbidities and frailty. At the same time, minimally invasive strategies such as Minimally Invasive Direct Coronary Artery Bypass Grafting (MIDCAB) and Percutaneous Coronary Interventions (PCI) have been developed, which might be more appealing for this group of patients. As a result, the landscape of options for myocardial revascularization is evolving while adequate use of all resources is required to ensure optimal patient care. Heart Teams are confronted with the challenge of incorporating the new minimally invasive strategies into the decision process, yet current guidelines do not fully address this challenge. In this review, the current evidence regarding outcomes, indications, benefits, and risks of off-pump coronary artery bypass grafting (OPCAB), MIDCAB, PCI, and hybrid coronary revascularization (HCR) are discussed. Based on this evidence and on experiences from Heart Team discussions, a new decision tree is proposed that incorporates recent advances in minimally invasive revascularization strategies, thereby optimizing adequate delivery of care for each individual patient's needs. Introducing all important considerations in a logical way, this tool facilitates the decision-making process and might ensure appropriate use of resources and optimal care for individual patients.

Management of perioperative myocardial ischaemia after isolated coronary artery bypass graft surgery

Objectives

Updated knowledge about perioperative myocardial ischaemia (MI) after coronary artery bypass grafting (CABG) and treatment of acute graft failure is needed. We analysed main factors associated with perioperative MI and effects of immediate coronary angiography-based treatment strategy on patient outcome.

Methods

Among 1119 consecutive patients with coronary artery disease who underwent isolated CABG between January 2011 and December 2015, 43 (3.8%) patients underwent urgent coronary angiography due to suspected perioperative MI. All the data were prospectively collected and retrospectively analysed. The primary endpoint was 30-day mortality; postoperative left ventricular ejection fraction) and major adverse cardiac events were secondary endpoints.

Results

Overall, 30-day mortality in patients with CABG was 1.4% while in patients who developed perioperative MI was 9% (4 patients). Angiographic findings included incorrect graft anastomosis, graft spasm, dissection, acute coronary artery thrombotic occlusion and ischaemia due to incomplete revascularisation. Emergency reoperation (Redo) was performed in 14 (32%), acute percutaneous coronary intervention (PCI) in 15 (36%) and conservative treatment (Non-op) in 14 patients. Demographic and preoperative clinical characteristics between the groups were comparable. Postoperative LVEF was significantly reduced in the Redo group (45% post-op vs 53% pre-op) and did not change in groups PCI (56% post-op vs 57% pre-op) and Non-op (58% post-op vs 57% pre-op).

Conclusions

Urgent angiography allows identification of the various underlying causes of perioperative MI and urgent treatment when this is needed. Urgent PCI may be associated with improved clinical outcome in patients with early graft failure.

Coronary artery bypass grafting in patients with low ejection fraction: what are the risk factors?

BACKGROUND

Left ventricular (LV) dysfunction alone is insufficient as an independent predictor of postoperative complications and mortality in coronary artery bypass graft (CABG) surgery. Our objective was to identify additional independent risk factors in patients with low left ventricle ejection fraction (EF) who underwent CABG.

METHODS

We retrospectively analyzed CABG results of 346 consecutive patients with low EF (≤30%) in a single institution between 2009 and 2015. The primary study endpoint was 30-day all-cause mortality. The secondary endpoints were the development of major adverse cardiac events (MACE) and renal complications after operation. A subgroup of patients underwent additional analyses of the interaction between extents of viable myocardium and postoperative endpoints.

RESULTS

The analysis showed that preoperative hemodynamic instability (AOR=4.57; 95% CI: 1.53-13.7, P=0.007) and serum creatinine >166 µmol/L (AOR=3.46; 95% CI: 1.12-10.7, P=0.031) were independent predictors of 30-day death. Both urgent and emergency operations were predictors for MACE (P=0.038; P=0.005) and renal complications (P=0.004; P=0.007). Pre-existing diabetes mellitus increased the likelihood of renal complications (P=0.020). In the sub-analysis of patients with viable myocardium, the mortality was significantly lower with predicted mortality (P=0.014).

CONCLUSIONS

Patients with significant LV dysfunction undergoing isolated CABG have fair short-term survival even with EF less than 30%. Hemodynamic instability prior to operation and preoperative kidney dysfunction are strong predictors of mortality in patients with low EF. Favorable coronary targets, meticulous operative techniques, and optimal surgical timing before hemodynamic deterioration occurs are essential to minimize the risk of revascularization complications and early postoperative mortality.

Impact of coronary angiography early after CABG for suspected postoperative myocardial ischemia

Background

The incidence of perioperative myocardial infarction is reported to 2–8%. The aim of the study (retrospectively registered) was to evaluate whether control coronary angiography after surgery is useful in case of suspected postoperative myocardial ischemia.

Methods

All patients who demonstrated signs of myocardial ischemia post CABG and underwent coronary angiography from 6/2008 to 06/2015 were retrospectively analyzed. Myocardial ischemia post CABG was defined as an increase of CK/CK-MB, occasionally associated with arrhythmias or low output syndrome.

Results

Overall, 108 patients (age 66 ± 9 years) demonstrated signs of myocardial ischemia post CABG and underwent coronary angiography corresponding to an incidence of 2.2%. Of them, 70 patients (65%) demonstrated graft pathologies. A therapeutic consequence was drawn in 62 Patients (57%), which consisted of redo surgery in 10 patients (9%) and PCI with stent placement in 52 patients (48%). Of the remaining 46 patients, 29 patients showed intact bypass grafts (27%), whereas 17 patients had minor pathologies (16%). Demographic data including the extent of the coronary artery disease, urgency of operation, comorbidities, EuroScore, surgical technique, postoperative lab tests and transfusion requirements were comparable among the groups. Redo surgery patients had prior PCI in 33% of patients, which was much higher than in the other groups. Patients with reintervention had a 30d-mortality rate of 13%, conservatively treated patients only 2.2%. Mortality was highest after redo surgery with 25%.

Conclusions

Postoperative coronary angiography is a useful tool with a significant therapeutic value. Pathological findings mandate further revascularization therapy in roughly half of the patients. PCI is a safe choice in the majority of patients, redo surgery is much less indicated.

Survival results of postoperative coronary angiogram for treatment of perioperative myocardial ischaemia following coronary artery bypass grafting: a single-centre experience

OBJECTIVES

Although perioperative myocardial ischaemia (PMI) is a well-known complication following coronary artery bypass grafting (CABG), standard strategies for its diagnosis and treatment are so far not defined. In this study, we sought to evaluate the impact on survival of postoperative coronary angiogram for management of patients with PMI after CABG.

METHODS

Overall, 4028 patients underwent isolated CABG in a single-centre institution between January 2006 and September 2013. A total of 168 (4.2%) patients received postoperative coronary angiogram because of diagnosis of PMI. These patients were matched on the basis of gender, age at surgery and date of surgery, with 336 (1:2 ratio) CABG patients without PMI to determine the impact of the PMI management.

RESULTS

A total of 476 grafts were examined (263 venous grafts, 196 internal mammary artery grafts and 17 radial artery grafts). Almost three-quarters of the 168 PMI (74.4%) patients underwent postoperative coronary angiogram within 24 h of surgery. Normal postoperative coronary angiogram, graft failure and new native vessels occlusion were observed in 23.2%, 52.4% and 24.4% of patients, respectively. A total of 30 (17.9%) patients underwent surgical revision of grafts, whereas 60 (35.7%) patients were treated with percutaneous coronary intervention. Eighteen (10.7%) PMI patients died during the hospital stay compared with 6 (1.8%) patients in the non-PMI group. Survival rates at 7 years were 62.5% in the PMI group and 81.1% in non-PMI group (P < 0.001). After multivariable adjustment PMI (P < 0.001; hazard ratio 3.17, 95% confidence interval 2.12-4.73) turned out to be an independent predictor of mortality on follow-up. Moreover, further subanalysis revealed that delayed postoperative coronary angiogram (>24 h after surgery) was an independent predictor of poorer mid-term survival (P = 0.008; hazard ratio 3.62, 95% confidence interval 1.41-9.33).

CONCLUSIONS

PMI after CABG is associated with a significantly poorer survival. A prompt postoperative management must always be considered. Further prospective studies are required to confirm our results.

Coronary artery bypass graft surgery complications: A review for emergency clinicians

INTRODUCTION

Coronary artery bypass graft (CABG) surgery remains a high-risk procedure, and many patients require emergency department (ED) management for complications after surgery.

OBJECTIVE

This narrative review provides an evidence-based summary of the current data for the emergency medicine evaluation and management of post-CABG surgery complications.

DISCUSSION

While there has been a recent decline in all cardiac revascularization procedures, there remains over 200,000 CABG surgeries performed in the United States annually, with up to 14% of these patients presenting to the ED within 30 days of discharge with post-operative complications. Risk factors for perioperative mortality and morbidity after CABG surgery can be divided into three categories: patient characteristics, clinician characteristics, and postoperative factors. Emergency physicians will be faced with several postoperative complications, including sternal wound infections, pneumonia, thromboembolic phenomena, graft failure, atrial fibrillation, pulmonary hypertension, pericardial effusion, strokes, renal injury, gastrointestinal insults, and hemodynamic instability. Critical patients should be evaluated in the resuscitation bay, and consultation with the primary surgical team is needed, which improves patient outcomes. This review provides several guiding principles for management of acute complications. Understanding these complications and an approach to the management of hemodynamic instability is essential to optimizing patient care.

CONCLUSIONS

Postoperative complications of CABG surgery can result in significant morbidity and mortality. Physicians must rapidly diagnose these conditions while evaluating for other diseases. Early surgical consultation is imperative, as is optimizing the patient's hemodynamics, including preload, heart rate, cardiac rhythm, contractility, and afterload.

Control angiography for perioperative myocardial Ischemia after coronary surgery: meta-analysis

BACKGROUND

Perioperative myocardial ischemia (PMI) in patients undergoing coronary artery bypass grafting (CABG) is associated with poor outcome. The aim of this study was to pool the available data on the outcome after control angiography and repeat revascularization in patients with perioperative myocardial ischemia (PMI) after coronary artery bypass grafting (CABG).

METHODS

A literature review was performed through PubMed, Scopus, ScienceDirect and Google Scholar to identify studies published since 1990 evaluating the outcome of PMI after CABG.

RESULTS

Nine studies included 1104 patients with PMI after CABG and 1056 of them underwent control angiography early after CABG. Pooled early mortality after reoperation for PMI without control angiography was 43.6% (95%CI 29.7-57.6%) and 79.8% of them (95%CI 64.4-95.2%) had an acute graft failure detected at reoperation. Among patients who underwent control angiography for PMI, 31.7% had a negative finding at angiography (95%CI 25.6-37.8%) and 62.1% had an acute graft failure (95%CI 56.6-67.6%). Repeat revascularization was performed after early control angiography in 46.3% of patients (95%CI 39.9-52.6%; 54.2% underwent repeat surgical revascularization; 45.8% underwent percutaneous coronary intervention). Pooled early mortality after control angiography with or without repeat revascularization was 8.9% (95%CI 6.7-11.1%). Three studies reported on early mortality rates which did not differ between repeat surgical revascularization and PCI (11.7% vs. 9.2%, respectively; risk ratio 1.45, 95%CI 0.67-3.11). In these three series, early mortality after conservative treatment was 5.9% (95%CI 3.6-8.2%).

CONCLUSIONS

Control angiography seems to be a valid life-saving strategy to guide repeat revascularization in hemodynamically stable patients suffering PMI after CABG.

Acute coronary angiography after coronary artery bypass grafting

OBJECTIVES

Coronary angiography is the golden standard when myocardial ischemia after CABG occurs. We summarize our experience of acute coronary angiography after CABG.

DESIGN

All 4446 patients (mean age 68 ± 9 years, 22% women) who underwent CABG 2007 to 2012 were included in this retrospective observational study. Incidence, indications, findings, measures of acute angiography after CABG was assessed. Outcome variables were compared between patients who underwent angiography and those who did not.

RESULTS

Eighty-seven patients (2%) underwent acute coronary angiography. Patients undergoing angiography had ECG changes (92%), echocardiographic alterations (48%), hemodynamic instability (28%), angina (15%), and/or arrhythmia (13%). Positive findings were detected in 69% of the cases. Only ECG changes as indication for angiography had a moderate association with positive findings, but the precision increased if other sign(s) of ischemia were present. Thirty-day mortality (7% versus 2%, p = 0.002) was higher and long-term-cumulative survival lower (77% versus 87% at five years, p = 0.043) in angiography patients.

CONCLUSIONS

Acute angiography is a rare event after CABG. Postoperative myocardial ischemia leading to acute coronary angiography is associated with increased short-term and long-term mortality.

Implementation of the third universal definition of myocardial infarction after coronary artery bypass grafting: a survey study in Western Europe

Background

Diagnosing a postoperative myocardial infarction in patients undergoing coronary artery bypass grafting is challenging, as the normally used criteria are more difficult to interpret. The rate of implementation of the consensus‐based new diagnostic criteria for postoperative myocardial infarction proposed by the third universal definition of myocardial infarction is unknown. Therefore, the primary objective of this study was to address the implementation of the third universal definition of postoperative myocardial infarction following coronary artery bypass grafting.

Methods and Results

We conducted a web‐based survey by sending 4 waves of invitations via e‐mail to cardiothoracic surgeons in 12 Western European countries. Of the 302 participating cardiothoracic specialists, from 182 different centers, 213 (71%) were aware that troponin is the preferred biomarker and 112 (37%) knew that using a cut‐off level of >10 times the 99th percentile is recommended. Overall, 90 (30%) participants (strongly) agreed with implementation of this cut‐off level in their clinical practice. Troponin was used in clinical practice by 149 (49%) of the participants. In total, 117 (89%) of the 131 participants with a local guideline confirmed ECG changes as a diagnostic criterion in that guideline. ST segmental changes (75, 64%) were used more often for diagnosing postoperative myocardial infarction than Q waves (64, 55%) or new left bundle branch blocks (34, 29%).

Conclusions

Cardiac biomarkers and ECG changes were not used in concordance with the third universal definition, and only a minority had a positive attitude toward implementation of the proposed cut‐off level for troponin in their clinical practice.

Angiography for Management of Perioperative Myocardial Ischemia: Does it Have Any Role?

Objective

Perioperative myocardial ischemia (PMI) is a relatively rare but potentially fatal complication after coronary artery bypass grafting and is due to graft-related problems in a significant proportion of cases. The usual indicators of MI in the postoperative setting are unreliable and therefore have uncertain diagnostic value. Angiography, the criterion standard for preoperative angina, remains underused for evaluation of PMI. The aim of this study was to evaluate the role of angiography in the management of PMI.

Methods

Between January 2011 and September 2012, a total of 2312 isolated primary consecutive coronary artery bypass graft surgeries were performed, of which 2057 (89%) were carried out on the beating heart. Twenty-six (1.12%) of these patients needed perioperative angiography. The patients needing angiography were selected on the basis of a number of clinical, biochemical, and other diagnostic parameters

Results

Twenty-six patients with PMI required angiography, of which 18 (69 %) were found to have graft-related issues. The mean (SD) time between operation and angiography was 24.58 (6.71) hours. Of the 18 patients, 17 (94.44%) required surgical intervention and 1 patient was treated with angioplasty. There were 2 deaths (11.1%) in the group undergoing intervention. Angiographic findings included occluded vein graft (n = 7), narrowing of the left internal mammary artery (n = 3), and kinking or stretching of grafts (n = 8).

Conclusions

Angiography is useful in diagnosing graft-related problems in the perioperative period. In presence of signs of graft compromise, we suggest that having a low threshold for angiographic graft evaluation may be beneficial in a carefully selected subset of patients after coronary artery bypass.

Cardiac tamponade and para-aortic hematoma post elective surgical myocardial revascularization on a beating heart - a possible complication of the Lima-stitch and sequential venous anastomosis

Background

Off-pump coronary artery bypass (OPCAB) surgery can be associated with some intrinsic, but relatively rare complications. A pericardial effusion is a common finding after cardiac surgeries, but the prevalence of a cardiac tamponade does not exceed 2% and is less frequent after myocardial revascularization.

Authors believe that in our patient an injury of a nutritional pericardial or descending aorta vessel caused by the Lima stitch resulted in oozing bleeding, which gradually leaded to cardiac tamponade. The bleeding increased after introduction of double antiplatelet therapy and caused life-threatening hemodynamic destabilization. According to our knowledge it is the first report of such a complication after OPCAB.

Case presentation

We present a case of a 61-year old man, who underwent elective surgical myocardial revascularization on a beating heart. On the 11th postoperative day the patient was readmitted emergently to the intensive care unit for severe chest pain, dyspnoea and hypotension. Coronary angiographic control showed a patency of the bypass grafts and significant narrowing of circumflex artery, treated with angioplasty and stenting. The symptoms and hemodynamic instability exacerbated. A suspicion of dissection of the ascending aorta and para-aortic hematoma was stated on 16-slice cardiac computed tomography. The patient was referred to the Cardiovascular Surgery Clinic. Transthoracic echocardiography revealed cardiac tamponade. On transesophageal echocardiography there were no signs of the ascending aorta dissection, but a possible lesion of the descending aorta with para-aortic hematoma was visualized. Emergent rethoracotomy and cardiac tamponade decompression were performed. 12 days after intervention the control 64-slice computed tomography showed no lesions of the ascending or descending aorta. On one-year follow-up patient is in a good condition, the left ventricular function is preserved and there is no pathology in thoracic aorta on echocardiography.

Conclusions

Mechanical complications of surgical myocardial revascularization on a beating heart should be considered as a cause of the clinical and hemodynamic instability relatively early in the postoperative period. Echocardiographic examination must be the first step in diagnostics process in a patient after cardiac surgery.

Graft flow unaffected by full occlusion of left anterior descending artery during coronary artery bypass grafting in a porcine model

BACKGROUND

We investigated in a porcine model whether measuring both the flow distal to an anastomosis and the graft transit time flow (TTF) gives a more accurate picture of the true blood flow in the left anterior descending artery (LAD) than graft TTF measurement alone.

METHODS

We performed off-pump coronary artery bypass grafting (CABG)-left internal mammary artery (LIMA) to the LAD-on 5 Yorkshire-Landrace pigs. Snares were placed both proximal and distal to the anastomosis. Flow was measured with ultrasound and TTF. This was carried out on the LIMA and at 2 locations on the LAD. Measurements were performed at the following times: baseline, during proximal snaring, after proximal snare loosening, during distal snaring, after distal snare loosening, and during both proximal and distal snaring.

RESULTS

During distal snaring, the TTF dropped (P = .047), and the pulsatile index (PI) increased (P = .025), while the ultrasound flow in the LAD dropped (P = .002). During proximal and distal snaring, the ultrasound flow dropped (P = .005), but the TTF value did not change significantly, compared with baseline.

CONCLUSION

A high flow and a low PI were seen in the graft, both proximal and distal to the anastomosis, despite a fully occluded LAD. This result suggests that graft TTF measurement alone is not sufficient when performing CABG, and measurement of flow distal to the anastomosis is also necessary to determine the true blood flow in the LAD.