Angiographic investigation of the pathophysiology of perioperative myocardial infarction

Polygenic Risk Scores in Myocardial Injury After Noncardiac Surgery: A VISION Substudy

BACKGROUND

Myocardial injury after noncardiac surgery (MINS) is the most prevalent vascular complication following surgical procedures. Although the revised cardiac risk index (RCRI) is widely used to predict postoperative cardiovascular complications, its predictive accuracy is suboptimal.

OBJECTIVES

Considering genetic influences may improve risk prediction. The authors propose integrating polygenic risk scores (PRS) with the RCRI to enhance MINS prediction. Identification of PRS associated with MINS could provide pathophysiological insights.

METHODS

This is a case-control study nested within the Vascular Events in Noncardiac Surgery Participants Cohort Evaluation cohort, including patients aged 45 and above who underwent noncardiac surgery. Daily troponin levels were measured preoperatively and on days 1, 2, and 3 postoperatively. PRS was computed for MINS risk factors using publicly available summary statistics. Logistic regression models were used to assess the association between each PRS and MINS. PRS discrimination was assessed independently and in combination with RCRI.

RESULTS

A total of 253 MINS cases were matched with 253 controls, adjusted for age, sex, and limited to individuals of European ancestry (ntotal = 506). The type II diabetes (T2D) PRS (OR: 1.26; 95% CI: 1.00-1.58; P = 0.047) and the HbA1c PRS (OR: 1.26; 95% CI: 1.03-1.54; P = 0.026) were associated with MINS. No other PRS, including those for coronary artery disease, stroke, and lipid biomarkers, showed significant associations.

CONCLUSIONS

The T2D PRS and the HbA1c PRS were associated with an increased risk of MINS. The findings may reflect the multifactorial pathophysiology of MINS. Larger genetic studies and trials evaluating perioperative glucose management warrant consideration.

The relationship between the atherogenic index of plasma and postoperative myocardial injury following non-cardiac surgery under general anaesthesia: a retrospective cohort study

BACKGROUND

The atherogenic index of plasma (AIP) is a reliable lipid marker associated with coronary artery stenosis (CAS) and cardiovascular events. However, the relationship between AIP and myocardial injury after non-cardiac surgery (MINS) remains insufficiently explored.

METHODS

This retrospective study included adult patients who underwent non-cardiac surgery under general anaesthesia. The primary exposure was preoperative AIP, with MINS as the primary outcome. The predictive accuracy of AIP for MINS was assessed using the area under the curve (AUC). Restricted cubic splines (RCS) were used to explore the potential nonlinear relationship between AIP and MINS. Logistic regression analysis was conducted to examine the association of AIP with MINS. Subgroup and interaction analyses were carried out across multiple factors, including age, gender, body mass index, medical history, and the type of surgery (emergency or elective).

RESULTS

The cohort consisted of 1,160 adult patients, with a median preoperative AIP of -0.05. The incidence of MINS was 7.9%. The AUC for AIP in predicting MINS was 0.719, surpassing the AUCs of triglycerides and high-density lipoprotein cholesterol (0.644 and 0.683, respectively). RCS analysis demonstrated a linear relationship between AIP and MINS (P for nonlinear = 0.165). Patients in the highest quartile of AIP had significantly higher odds of developing MINS than those in the lowest quartile (adjusted OR, 8.05; 95% confidence interval [CI], 3.44 to 18.80; P < 0.001). The results across most subgroups were consistent with the primary analysis, showing no significant interaction effects.

CONCLUSIONS

A significant and independent linear relationship exists between preoperative AIP and the risk of MINS. As an economical and easily accessible lipid marker, AIP holds potential for preoperative screening of patients at risk of postoperative cardiovascular events.

Preventing, identifying and managing myocardial injury after non cardiac surgery - a narrative review

PURPOSE OF REVIEW

There is mounting and convincing evidence that patients with postoperative troponin elevation, with or without any clinical symptoms, are at higher risk for both, short- and long-term morbidity and mortality. Myocardial injury after noncardiac surgery (MINS) is a relatively newly described syndrome, and the pathogenesis is not fully understood yet. MINS is now an established syndrome and multiple guidelines address potential etiologies, triggers, as well as preventive and management strategies.

RECENT FINDINGS

Surveillance in high-risk patients is required, as most MINS would otherwise be missed. There is no reliable and established preventive strategy, but several potentially avoidable triggers like hypotension, pain and anemia have been identified. Managing patients with MINS postoperatively includes minimizing triggers (such as hemodynamic abnormalities and anemia) that can continue the damage. Long-term pharmacologic strategies include beta-blockers, statins, antiplatelet agents, and anticoagulation.

SUMMARY

MINS affects up to 20% of surgical patients, remains clinically mostly silent, but is associated with elevated morbidity and mortality. A multidisciplinary approach, that includes involvement of anesthesiologists, for the prevention, diagnosis, and treatment of MINS is recommended.

Periprocedural myocardial infarction and injury

Periprocedural myocardial infarction (PMI) and injury, pertinent to both cardiac and non-cardiac procedures, have gained increasing recognition in clinical practice. Over time, diverse definitions for diagnosing PMI have been developed and validated among patient populations undergoing coronary revascularization. However, this variety in definitions presents considerable challenges in clinical settings and complicates both the design and interpretation of clinical trials. The necessity to accurately diagnose PMI has spurred significant interest in establishing universally accepted and prognostically meaningful thresholds for cardiac biomarkers elevation and supportive ancillary criteria. In fact, elevations in cardiac biomarkers in line with the 4th Universal Definition of Myocardial Infarction, have been extensively confirmed to be associated with increased mortality and cardiovascular events. In the context of non-coronary cardiac procedures, such as Transcatheter Aortic Valve Implantation, there is a growing acknowledgment of both the high incidence rates and the adverse impact of PMI on patient outcomes. Similarly, emerging research underscores the significance of PMI and injury in non-cardiac surgery, highlighting the urgent need for effective prevention and risk management strategies in this domain.

Late Mortality After Myocardial Injury in Critical Care Non-Cardiac Surgery Patients Using Machine Learning Analysis

Myocardial injury after noncardiac surgery (MINS) increases mortality within 30 days. We aimed to evaluate the long-term impact of myocardial injury in a large cohort of patients admitted to intensive care after noncardiac surgery. All patients who stayed, at least, overnight with measurement of high-sensitive cardiac troponin were included. Clinical characteristics and occurrence of MINS were assessed between patients who died and survivors using chi-square test and Student t test. Variables with p <0.01 in the univariate model were included in the Cox regression model to identify predictor variables. Survival decision tree (SDT), a machine learning model, was also used to find the predictors and their correlations. We included 2,230 patients with mean age of 63.8±16.3 years, with most (55.6%) being women. The prevalence of MINS was 9.4% (209 patients) and there were 556 deaths (24.9%) in a median follow-up of 6.7 years. Univariate analysis showed variables associated with late mortality, namely: MINS, arterial hypertension, previous myocardial infarction, atrial fibrillation, dementia, urgent surgery, peripheral artery disease (PAD), chronic health status, and age. These variables were included in the Cox regression model and SDT. The predictor variables of all-cause death were MINS (hazard ratio [HR] 2.21; 95% confidence interval [CI] 1.77 to 2.76), previous myocardial infarction (HR 1.47; 95% CI 1.14 to 1.89); urgent surgery (HR 1.24; 95% CI 1.01 to 1.52), PAD (HR 1.83; 95% CI 1.23 to 2.73), dementia (HR 2.54; 95% CI 1.86 to 3.46) and age (HR 1.05; 95% CI 1.04 to 1.06). SDT had the same predictors, except PAD. In conclusion, increased high-sensitive troponin levels in patients who underwent noncardiac surgery raised the risk of short and late mortality.

The Impact of Perioperative Morbidities, Lack of Discharge Aspirin, and Lack of Discharge Statin on Long Term Survival Following EVAR

OBJECTIVE

Adverse perioperative events and discharge medications both have the potential to impact survival following endovascular abdominal aortic aneurysm repair (EVAR). We hypothesize that variables such as blood loss, reoperation in the same hospital admission, and lack of discharge statin/aspirin have significant effect on long term survival following EVAR. Similarly, other perioperative morbidities, are hypothesized to affect long term mortality. Quantifying the mortality effect of perioperative events and treatment emphasizes to physicians the critical nature of preoperative optimization, case planning, operative execution and postoperative patient management.

METHODS

All EVAR in the Vascular Quality Initiative between 2003 and 2021 were queried. Exclusions were: ruptured/symptomatic aneurysm; concomitant renal artery or supra-renal intervention at the time of EVAR; conversion to open aneurysm repair at the time of initial operation; and undocumented mortality status at the 5 year mark postoperatively. 18,710 patients met inclusion criteria. Multivariable Cox regression time dependent analysis was performed to investigate the strength of mortality association of the exposure variables. Standard demographic variables and pre-existing major co-morbidities were included in the regression analysis to account for disproportionate, deleterious co-variables amongst those experiencing the various morbidities. Kaplan-Meier survival analysis was performed to provide survival curves for the key variables.

RESULTS

Mean follow up was 5.99 years and 5-year survival for included patients was 69.2%. Cox regression revealed increased long term mortality to be associated with the following perioperative events: reoperation during the index hospital admission (HR 1.21, P = .034), perioperative leg ischemia (HR 1.34, P = .014), perioperative acute renal insufficiency (HR 1.24, P = .013), perioperative myocardial infarction (HR 1.87, P < .001), perioperative intestinal ischemia (HR 2.13, P < .001), perioperative respiratory failure (HR 2.15, P < .001), lack of discharge aspirin (HR 1.26, P < .001), and lack of discharge statin (HR 1.26, P < .001). The following pre-existing co-morbidities correlated with increased long term mortality (P < .001 for all) : body mass index under 20 kg/m2, hypertension, diabetes, coronary artery disease, reported history congestive heart failure, chronic obstructive pulmonary disease, peripheral artery disease, advancing age, baseline renal insufficiency and left ventricular ejection fraction less than 50%. Females were more likely to have EBL >300 mL, reoperation, perioperative MI, limb ischemia and acute renal insufficiency than males (P < .01 for all). Female sex trended but was not associated with increased long term mortality risk (HR 1.06, 95% CI .995-1.14, P = .072).

CONCLUSIONS

Survival after EVAR is improved with optimal operative planning to facilitate evading the need for reoperation and ensuring patients without contra-indication are discharged with aspirin and statin medications. Females and patients with pre-existing co-morbidity are at particularly higher risk for perioperative limb ischemia, renal insufficiency, intestinal ischemia and myocardial ischemia necessitating appropriate preparation and preventative measures.

NT-proBNP level as a substitute for myocardial perfusion scan in preoperative cardiovascular risk assessment in noncardiac surgery

BACKGROUND

Preoperative cardiovascular risk assessment is one of the main principles before noncardiac surgeries. Cardiac stress imaging, such as myocardial perfusion scan (MPS), is a proposed cardiovascular risk evaluation method according to the latest guidelines. Yet, its efficacy, along with the cost-effectiveness of the method, has been questioned in previous studies. Our study aims to evaluate the utility of N-terminal pro-b-type natriuretic peptide (NT-proBNP) level measurement in predicting postoperative cardiovascular complications in candidates who have undergone an MPS before surgery and compare the results.

METHODS

A cohort of 80 patients with a revised cardiac risk index score of one or more who were scheduled for moderate to high-risk noncardiac surgeries and met the criteria to undergo an MPS for risk assessment were included in the study. All of them underwent an MPS one week before surgery. Their preoperative NT-proBNP, troponin levels, and electrocardiograms were obtained one day before surgery and again on day three postoperative. The predictive efficacy of NT-proBNP levels and MPS were compared.

RESULTS

Seventy-eight patients underwent surgery, three of which exhibited a rise in troponin level, six showed changes on electrocardiogram, and pulmonary edema was detected in one, three days after surgery. There was no mortality in our patients. The sensitivity and specificity of the MPS for predicting postoperative cardiovascular complications were 100% and 66%, respectively. MPS also had a positive predictive value of 20% and a negative predictive value of 100% in our study. A 332.5 pg/ml cut-off value for NT-proBNP level yielded a sensitivity of 100%, specificity of 79.2%, positive predictive value of 40%, and negative predictive value of 100%.

CONCLUSIONS

Our study reveals the incremental specificity and positive predictive value of NT-proBNP level measurement in preoperative cardiovascular risk evaluation compared to MPS. Given the low feasibility, high costs, and disappointing predictive value of MPS, preoperative NT-proBNP level assessment can be substituted. This method can assist anesthesiologists and surgeons with precisely detecting at-risk patients resulting in taking proper measures to reduce the morbidity and mortality of the proposed patients before and during surgeries.

Long-term outcomes of perioperative myocardial infarction/injury after non-cardiac surgery

AIMS

Perioperative myocardial infarction/injury (PMI) following non-cardiac surgery is a frequent cardiac complication. Better understanding of the underlying aetiologies and outcomes is urgently needed.

METHODS AND RESULTS

Aetiologies of PMIs detected within an active surveillance and response programme were centrally adjudicated by two independent physicians based on all information obtained during clinically indicated PMI work-up including cardiac imaging among consecutive high-risk patients undergoing major non-cardiac surgery in a prospective multicentre study. PMI aetiologies were hierarchically classified into 'extra-cardiac' if caused by a primarily extra-cardiac disease such as severe sepsis or pulmonary embolism; and 'cardiac', further subtyped into type 1 myocardial infarction (T1MI), tachyarrhythmia, acute heart failure (AHF), or likely type 2 myocardial infarction (lT2MI). Major adverse cardiac events (MACEs) including acute myocardial infarction, AHF (both only from day 3 to avoid inclusion bias), life-threatening arrhythmia, and cardiovascular death as well as all-cause death were assessed during 1-year follow-up. Among 7754 patients (age 45-98 years, 45% women), PMI occurred in 1016 (13.1%). At least one MACE occurred in 684/7754 patients (8.8%) and 818/7754 patients died (10.5%) within 1 year. Outcomes differed starkly according to aetiology: in patients with extra-cardiac PMI, T1MI, tachyarrhythmia, AHF, and lT2MI 51%, 41%, 57%, 64%, and 25% had MACE, and 38%, 27%, 40%, 49%, and 17% patients died within 1 year, respectively, compared to 7% and 9% in patients without PMI. These associations persisted in multivariable analysis.

CONCLUSION

At 1 year, most PMI aetiologies have unacceptably high rates of MACE and all-cause death, highlighting the urgent need for more intensive treatments.

STUDY REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02573532.

Chest pain in patients recovering from noncardiac surgery: A retrospective analysis

STUDY OBJECTIVE

Chest pain is relatively common postoperatively. Myocardial infarction (MI) is one cause of chest pain after surgery, but chest pain also results from less severe conditions. Because of its potential severity, chest pain usually prompts the activation of Rapid Response Systems (RRS). While chest pain is a cardinal symptom of myocardial ischemia in the non-surgical setting, the significance and relevance of chest pain after noncardiac surgery remains unclear.

DESIGN

We conducted a retrospective analysis of noncardiac surgical inpatients for whom postoperative chest pain triggered our multidisciplinary RRS.

SETTING

Surgical wards at Cleveland Clinic, Cleveland, OH.

PATIENTS

Postsurgical patients after noncardiac surgery in whom the RSS system was activated for chest pain.

INTERVENTIONS

RRS specified interventions like ECG readings, troponin measurements, transfer to ICU.

MEASUREMENTS

Our primary outcome was MI. Secondary outcomes included the proportion of patients who had an ECG performed, troponin measurements, echocardiography, cardiac catheterization, and were admitted to the Intensive Care Unit (ICU).

MAIN RESULTS

5850 surgical patients experienced postoperative chest pain and triggered an RRS activation between 2009 and 2019. A total of 3110 patients had troponin T measured within 6 h after RRS activation, and 538 of them (17%) had elevated troponin, meeting the Fourth Universal Definition criteria for MI. Additionally, 2 patients had ST-segment elevation infarction (STEMI) without troponin measurement. Among the 540 patients with MI, only 19 (3.5%) were diagnosed with a STEMI by ECG, 388 (72%) had echocardiography, 43 patients (8%) had cardiac catheterization, 8 patients (1.5%) required emergent cardiac surgery, and 424 (79%) were admitted to an ICU.

CONCLUSION

Chest pain is a serious clinical sign, often indicating a postoperative myocardial infarction, and therefore should be taken seriously. Troponin screening should be routinely considered in postsurgical patients who report chest pain.

Patient- and procedure-related factors in the pathophysiology of perioperative myocardial infarction/injury

BACKGROUND

Perioperative myocardial infarction/injury (PMI) is a frequent, often missed and incompletely understood complication of noncardiac surgery. The aim of this study was to evaluate whether patient- or procedure-related factors are more strongly associated to the development of PMI in patients undergoing repeated noncardiac surgery.

METHODS

In this prospective observational study, patient- and procedure-related factors were evaluated for contribution to PMI using: 1) logistic regression modelling with PMI as primary endpoint, 2) evaluation of concordance of PMI occurrence in the first and the second noncardiac surgery (surgery 1 and 2). and 3) the correlation of the extent of cardiomyocyte injury quantified by high-sensitivity cardiac troponin T between surgery 1 and 2. The secondary endpoint was all-cause mortality associated with PMI reoccurrence in surgery 2.

RESULTS

Among 784 patients undergoing repeated noncardiac surgery (in total 1'923 surgical procedures), 116 patients (14.8%) experienced PMI during surgery 1. Among these, PMI occurred again in surgery 2 in 35/116 (30.2%) patients. However, the vast majority of patients developing PMI during surgery 2 (96/131, 73.3%) had not developed PMI during surgery 1 (phi-coefficient 0.150, p < 0.001). The correlation between the extent of cardiomyocyte injury occurring during surgery 1 and 2 was 0.153. All-cause mortality following a second PMI in surgery 2 was dependent on time since surgery (adjusted hazard ratio 5.6 within 30 days and 2.4 within 360 days).

CONCLUSIONS

In high-risk patients, procedural factors are more strongly associated with occurrence of PMI than patient factors, but patient factors are also contributors to the occurrence of PMI.

Cardiovascular imaging following perioperative myocardial infarction/injury

Patients developing perioperative myocardial infarction/injury (PMI) have a high mortality. PMI work-up and therapy remain poorly defined. This prospective multicenter study included high-risk patients undergoing major non-cardiac surgery within a systematic PMI screening and clinical response program. The frequency of cardiovascular imaging during PMI work-up and its yield for possible type 1 myocardial infarction (T1MI) was assessed. Automated PMI detection triggered evaluation by the treating physician/cardiologist, who determined selection/timing of cardiovascular imaging. T1M1 was considered with the presence of a new wall motion abnormality within 30 days in transthoracic echocardiography (TTE), a new scar or ischemia within 90 days in myocardial perfusion imaging (MPI), and Ambrose-Type II or complex lesions within 7 days of PMI in coronary angiography (CA). In patients with PMI, 21% (268/1269) underwent at least one cardiac imaging modality. TTE was used in 13% (163/1269), MPI in 3% (37/1269), and CA in 5% (68/1269). Cardiology consultation was associated with higher use of cardiovascular imaging (27% versus 13%). Signs indicative of T1MI were found in 8% of TTE, 46% of MPI, and 63% of CA. Most patients with PMI did not undergo any cardiovascular imaging within their PMI work-up. If performed, MPI and CA showed high yield for signs indicative of T1MI.Trial registration: https://clinicaltrials.gov/ct2/show/NCT02573532 .

Perioperative Myocardial Infarction in Free Flap for Head and Neck Reconstruction

INTRODUCTION

Acute myocardial infarction (AMI) is a postoperative complication of major surgical procedures, including free flap surgery. It is the most common cause of postoperative morbidity and mortality. Moreover, patients receiving free flap reconstruction for the head and neck have significant risk factors such as coexisting coronary artery disease (CAD). Our primary aim was to ascertain predictors of perioperative AMI to enable early detection and consequently early treatment of perioperative AMI. Our secondary aim was to determine the group of patients who would be at a high risk for perioperative AMI after free flap surgery.

MATERIALS AND METHODS

This retrospective study enrolled patients who underwent free flap reconstruction surgery at the Division of Plastic and Reconstructive Surgery of Taipei Veterans General Hospital between 2013-01 and 2017-12.

RESULTS

This study included 444 patients and 481 free flap head and neck reconstruction surgeries. Fifteen (3.1%) patients were diagnosed with perioperative AMI. Statistical analysis of the variables revealed that patients with underlying CAD or cerebrovascular accident (CVA) were at a high risk of developing perioperative AMI (odds ratio: 6.89 and 11.11, respectively). The flap failure rate was also higher in patients with perioperative AMI compared with those without perioperative AMI (P = 0.015).

CONCLUSIONS

Patients with underlying diseases, such as CAD or CVA, constituted high-risk groups for perioperative AMI.

Type 2 MI and Myocardial Injury in the Era of High-sensitivity Troponin

Troponin has been the cornerstone of the definition of MI since its introduction to clinical practice. High-sensitivity troponin has allowed clinicians to detect degrees of myocardial damage at orders of magnitude smaller than previously and is challenging the definitions of MI, with implications for patient management and prognosis. Detection and diagnosis are no doubt enhanced by the greater sensitivity afforded by these markers, but perhaps at the expense of specificity and clarity. This review focuses on the definitions, pathophysiology, prognosis, prevention and management of type 2 MI and myocardial injury. The five types of MI were first defined in 2007 and were recently updated in 2018 in the fourth universal definition of MI. The authors explore how this pathophysiological classification is used in clinical practice, and discuss some of the unanswered questions in this era of availability of high-sensitivity troponin.

Pro-Con Debate: Cardiac Troponin Measurement as Part of Routine Follow-up of Myocardial Damage Following Noncardiac Surgery

Elevated troponin levels within 3 days of surgery, independent of the presence of symptoms, are strongly linked to increased risk of short- and long-term morbidity and mortality. However, the value of screening with troponin measurements is controversial. The Canadian Cardiovascular Society guidelines on perioperative cardiac risk assessment and management for patients who undergo noncardiac surgery recommends measuring daily troponin for 48 to 72 hours after surgery in high-risk patients. Nevertheless, others doubt this recommendation, in part because postoperative elevated levels of troponin describe very little in terms of disease or event-specific pathogenesis and etiology, and thus, tailoring an intervention remains a challenge. This Pro-Con debate offers evidence-based data to stimulate physician understanding of daily practice and its significance in this matter, and assist in determining whether to use (Pro) or not to use (Con) this surveillance.

Diagnosis and Management of Patients With Myocardial Injury After Noncardiac Surgery: A Scientific Statement From the American Heart Association

Myocardial injury after noncardiac surgery is defined by elevated postoperative cardiac troponin concentrations that exceed the 99th percentile of the upper reference limit of the assay and are attributable to a presumed ischemic mechanism, with or without concomitant symptoms or signs. Myocardial injury after noncardiac surgery occurs in ≈20% of patients who have major inpatient surgery, and most are asymptomatic. Myocardial injury after noncardiac surgery is independently and strongly associated with both short-term and long-term mortality, even in the absence of clinical symptoms, electrocardiographic changes, or imaging evidence of myocardial ischemia consistent with myocardial infarction. Consequently, surveillance of myocardial injury after noncardiac surgery is warranted in patients at high risk for perioperative cardiovascular complications. This scientific statement provides diagnostic criteria and reviews the epidemiology, pathophysiology, and prognosis of myocardial injury after noncardiac surgery. This scientific statement also presents surveillance strategies and treatment approaches.

Myocardial injury in noncardiac surgery

Myocardial injury is defined as an elevation of cardiac troponin (cTn) levels with or without associated ischemic symptoms. Robust evidence suggests that myocardial injury increases postoperative mortality after noncardiac surgery. The diagnostic criteria for myocardial injury after noncardiac surgery (MINS) include an elevation of cTn levels within 30 d of surgery without evidence of non-ischemic etiology. The majority of cases of MINS do not present with ischemic symptoms and are caused by a mismatch in oxygen supply and demand. Predictive models for general cardiac risk stratification can be considered for MINS. Risk factors include comorbidities, anemia, glucose levels, and intraoperative blood pressure. Modifiable factors may help prevent MINS; however, further studies are needed. Recent guidelines recommend routine monitoring of cTn levels during the first 48 h post-operation in high-risk patients since MINS most often occurs in the first 3 days after surgery without symptoms. The use of cardiovascular drugs, such as aspirin, antihypertensives, and statins, has had beneficial effects in patients with MINS, and direct oral anticoagulants have been shown to reduce the mortality associated with MINS in a randomized controlled trial. Myocardial injury detected before noncardiac surgery was also found to be associated with postoperative mortality, though further studies are needed.

Postoperative Myocardial Injury in Patients Classified as Low Risk Preoperatively Is Associated With a Particularly Increased Risk of Long-Term Mortality After Noncardiac Surgery

Background

Prior studies have shown an association between myocardial injury after noncardiac surgery (MINS) and all‐cause mortality in patients following noncardiac surgery. However, the association between preoperative risk assessments, Revised Cardiac Risk Index and American College of Surgeons National Surgical Quality Improvement Program, and postoperative troponin elevations and long‐term mortality is unknown.

Methods and Results

A retrospective chart review identified 548 patients who had a troponin I level drawn within 14 days of noncardiac surgery that required an overnight hospital stay. Patients aged 40 to 80 years with at least 2 cardiovascular risk factors were included, while those with trauma, pulmonary embolism, and neurosurgery were excluded. Kaplan–Meier survival and odds ratio (OR) with sensitivity/specificity analysis were performed to assess the association between preoperative risk and postoperative troponin elevation and all‐cause mortality at 1 year. Overall, 69%/31% were classified as low‐risk/high‐risk per the Revised Cardiac Risk Index and 66%/34% per American College of Surgeons National Surgical Quality Improvement Program. Comparing the low‐risk versus high‐risk groups, preoperative risk assessment was not associated with either postoperative troponin elevation or 1‐year mortality. MINS portended a 1‐year mortality of OR, 3.9 (95% CI, 2.44–6.33) in the total population. Patients classified as low risk preoperatively with MINS had the highest risk of 1‐year mortality (OR, 9.6; 95% CI, 4.27–24.38), with a low prevalence of statin use.

Conclusions

Current preoperative risk stratification tools do not prognosticate the risk of postoperative troponin elevation and all‐cause mortality at 1 year. Interestingly, patients classified as low risk preoperatively with MINS had a markedly higher 1‐year mortality risk compared with the general population, and most of them are not taking a statin. Our results suggest that evaluating preoperatively low‐risk patients for MINS presents an opportunity for prognostication, risk reclassification, and initiating therapies such as statins to mitigate long‐term risk.

Perioperative pharmacotherapy to prevent cardiac complications in patients undergoing noncardiac surgery

Introduction: Despite advances in surgical and anesthetic techniques, perioperative cardiovascular complications are a major cause of 30-day perioperative mortality. Major cardiovascular complications after noncardiac surgery include myocardial ischemia, congestive heart failure, arrhythmias, and cardiac arrest. Along with surgical risk assessment, perioperative medical optimization can reduce the rates and clinical impact of these complications.Areas Covered: In this review, the authors discuss the pharmacological basis, existing evidence, and professional society recommendations for drug management in preventing cardiovascular complications in patients undergoing noncardiac surgery.Expert opinion: Perioperative management of cardiovascular disease is an increasingly important and growing area of clinical practice. Societal guidelines regarding the use of most routine cardiovascular medications are based on a number of large clinical studies and provide a basic foundation to guide management. However, the heterogeneous nature of patients, as well as surgeries, makes it practically impossible to devise a 'one size fits all' recommendation in this setting. Thus, the importance of a more individualized approach to perioperative risk stratification and management is being increasingly recognized. The underlying comorbidities and cardiac profile as well as the risk of cardiac complications associated with the planned surgery must be factored in to understand the nuance of the management strategies.

Myocardial Injury After Noncardiac Surgery: Preoperative, Intraoperative, and Postoperative Aspects, Implications, and Directions

Myocardial injury after noncardiac surgery (MINS) differs from myocardial infarction in being defined by troponin elevation apparently from cardiac ischemia with or without signs and symptoms. Such myocardial injury is common, silent, and strongly associated with mortality. MINS is usually asymptomatic and only detected by routine troponin monitoring. There is currently no known safe and effective prophylaxis for perioperative myocardial injury. However, appropriate preoperative screening may help guide proactive postoperative preventative actions. Intraoperative hypotension is associated with myocardial injury, acute kidney injury, and death. Hypotension is common and largely undetected in the postoperative general care floor setting, and independently associated with myocardial injury and mortality. Critical care patients are especially sensitive to hypotension, and the risk appears to be present at blood pressures previously regarded as normal. Tachycardia appears to be less important. Available information suggests that clinicians would be prudent to avoid perioperative hypotension.

Non-cardiac surgery in patients with coronary artery disease: risk evaluation and periprocedural management

Perioperative cardiovascular complications are important causes of morbidity and mortality associated with non-cardiac surgery, particularly in patients with coronary artery disease (CAD). Although preoperative cardiac risk assessment can facilitate the identification of vulnerable patients and implementation of adequate preventive measures, excessive evaluation might lead to undue resource utilization and surgical delay. Owing to conflicting data, there remains some uncertainty regarding the most beneficial perioperative strategy for patients with CAD. Antithrombotic agents are the cornerstone of secondary prevention of ischaemic events but substantially increase the risk of bleeding. Given that 5-25% of patients undergoing coronary stent implantation require non-cardiac surgery within 2 years, surgery is the most common reason for premature cessation of dual antiplatelet therapy. Perioperative management of antiplatelet therapy, which necessitates concomitant evaluation of the individual thrombotic and bleeding risks related to both clinical and procedural factors, poses a recurring dilemma in clinical practice. Current guidelines do not provide detailed recommendations on this topic, and the optimal approach in these patients is yet to be determined. This Review summarizes the current data guiding preoperative risk stratification as well as periprocedural management of patients with CAD undergoing non-cardiac surgery, including those treated with stents.

Accuracy of Physicians in Differentiating Type 1 and Type 2 Myocardial Infarction Based on Clinical Information

Background

Physicians commonly judge whether a myocardial infarction (MI) is type 1 (thrombotic) vs type 2 (supply/demand mismatch) based on clinical information. Little is known about the accuracy of physicians’ clinical judgement in this regard. We aimed to determine the accuracy of physicians’ judgement in the classification of type 1 vs type 2 MI in perioperative and nonoperative settings.

Methods

We performed an online survey using cases from the Optical Coherence Tomographic Imaging of Thrombus (OPTIMUS) Study, which investigated the prevalence of a culprit lesion thrombus based on intracoronary optical coherence tomography (OCT) in patients experiencing MI. Four MI cases, 2 perioperative and 2 nonoperative, were selected randomly, stratified by etiology. Physicians were provided with the patient’s medical history, laboratory parameters, and electrocardiograms. Physicians did not have access to intracoronary OCT results. The primary outcome was the accuracy of physicians' judgement of MI etiology, measured as raw agreement between physicians and intracoronary OCT findings. Fleiss’ kappa and Gwet’s AC1 were calculated to correct for chance.

Results

The response rate was 57% (308 of 536). Respondents were 62% male; median age was 45 years (standard deviation ± 11); 45% had been in practice for > 15 years. Respondents’ overall accuracy for MI etiology was 60% (95% confidence interval [CI] 57%-63%), including 63% (95% CI 60%-68%) for nonoperative cases, and 56% (95% CI 52%-60%) for perioperative cases. Overall chance-corrected agreement was poor (kappa = 0.05), consistent across specialties and clinical scenarios.

Conclusions

Physician accuracy in determining MI etiology based on clinical information is poor. Physicians should consider results from other testing, such as invasive coronary angiography, when determining MI etiology.

Use of a Polygenic Risk Score Improves Prediction of Myocardial Injury After Non-Cardiac Surgery

BACKGROUND

While postoperative myocardial injury remains a major driver of morbidity and mortality, the ability to accurately identify patients at risk remains limited despite decades of clinical research. The role of genetic information in predicting myocardial injury after noncardiac surgery (MINS) remains unknown and requires large scale electronic health record and genomic data sets.

METHODS

In this retrospective observational study of adult patients undergoing noncardiac surgery, we defined MINS as new troponin elevation within 30 days following surgery. To determine the incremental value of polygenic risk score (PRS) for coronary artery disease, we added the score to 3 models of MINS risk: revised cardiac risk index, a model comprised entirely of preoperative variables, and a model with combined preoperative plus intraoperative variables. We assessed performance without and with PRSs via area under the receiver operating characteristic curve and net reclassification index.

RESULTS

Among 90 053 procedures across 40 498 genotyped individuals, we observed 429 cases with MINS (0.5%). PRS for coronary artery disease was independently associated with MINS for each multivariable model created (odds ratio=1.12 [95% CI, 1.02-1.24], P=0.023 in the revised cardiac risk index-based model; odds ratio, 1.19 [95% CI, 1.07-1.31], P=0.001 in the preoperative model; and odds ratio, 1.17 [95% CI, 1.06-1.30], P=0.003 in the preoperative plus intraoperative model). The addition of clinical risk factors improved model discrimination. When PRS was included with preoperative and preoperative plus intraoperative models, up to 3.6% of procedures were shifted into a new outcome classification.

CONCLUSIONS

The addition of a PRS does not significantly improve discrimination but remains independently associated with MINS and improves goodness of fit. As genetic analysis becomes more common, clinicians will have an opportunity to use polygenic risk to predict perioperative complications. Further studies are necessary to determine if PRSs can inform MINS surveillance.

Perioperative Heart-Brain Axis Protection in Obese Surgical Patients: The Nutrigenomic Approach

The number of obese patients undergoing cardiac and noncardiac surgery is rapidly increasing because they are more prone to concomitant diseases, such as diabetes, thrombosis, sleep-disordered breathing, cardiovascular and cerebrovascular disorders. Even if guidelines are already available to manage anesthesia and surgery of obese patients, the assessment of the perioperative morbidity and mortality from heart and brain disorders in morbidly obese surgical patients will be challenging in the next years. The present review will recapitulate the new mechanisms underlying the Heart-brain Axis (HBA) vulnerability during the perioperative period in healthy and morbidly obese patients. Finally, we will describe the nutrigenomics approach, an emerging noninvasive dietary tool, to maintain a healthy body weight and to minimize the HBA propensity to injury in obese individuals undergoing all types of surgery by personalized intake of plant compounds that may regulate the switch from health to disease in an epigenetic manner. Our review provides current insights into the mechanisms underlying HBA response in obese surgical patients and how they are modulated by epigenetically active food constituents.

Type 2 Myocardial Infarction: JACC Review Topic of the Week

Acute myocardial infarction (MI) can occur from increased myocardial oxygen demand and/or reduced supply in the absence of acute atherothrombotic plaque disruption; a condition called type 2 myocardial infarction (T2MI). As with any MI subtype, there must be clinical evidence of myocardial ischemia to make the diagnosis. This condition is increasingly diagnosed due to the increasing sensitivity of cardiac troponin assays and is associated with adverse short-term and long-term prognoses. Limited data exist defining optimal management strategies because T2MI is a heterogeneous entity with varying etiologies and triggers. Thus, these patients require individualized care. A major barrier is the absence of a uniform definition that can be operationalized with high reproducibility. This document provides a synthesis of the data about T2MI to assist clinicians' understanding of its pathobiology, when to deploy the diagnosis, and its associated treatments. It also clarifies prognosis, identifies gaps in knowledge, and provides recommendations for moving forward.

Preoperative biomarker evaluation for the prediction of cardiovascular events after major vascular surgery

OBJECTIVE

The cause of perioperative myocardial infarction (PMI) is postulated to involve hemodynamic stress or coronary plaque destabilization. We aimed to evaluate perioperative factors in patients with peripheral artery disease (PAD) undergoing major vascular surgery to determine the likely mechanisms and predictors of PMI.

METHODS

This was a prospective cohort study of 133 patients undergoing major vascular surgery including open abdominal aortic aneurysm (AAA) repair (n = 40) and major suprainguinal or infrainguinal arterial bypasses (non-AAA; n = 93). Preoperative assessment with history, physical examination, and peripheral artery tonometry was performed in addition to plasma sampling of biomarkers associated with inflammation and coronary plaque instability. The primary outcome was occurrence of a 30-day cardiovascular event (CVE; composite of PMI [troponin I elevation >99th percentile reference of ≥0.1 μg/L], stroke, or death).

RESULTS

Of 133 patients, 36 patients (27%) developed a 30-day CVE after vascular surgery, and all were PMI. Patients with 30-day CVE were older (75 ± 8 years vs 69 ± 10 years, mean ± standard deviation; P = .001), had higher prevalence of hypertension (94% vs 79%; P = .01) and preoperative beta-blocker therapy (50% vs 29%; P = .02), and had longer duration of surgery (5.1 ± 1.8 hours vs 4.0 ± 1.1 hours; P < .0001). Significant elevations in cystatin C, N-terminal pro-B-type natriuretic peptide (NT-proBNP), troponin I, high-sensitivity troponin T, matrix metalloproteinase 3, and osteoprotegerin occurred in those who developed 30-day CVE (all P < .05). Multivariate binary logistic regression identified AAA surgery and log-transformed NT-proBNP to be independent preoperative predictors of 30-day CVE (area under the receiver operating characteristic curve = 0.81).

CONCLUSIONS

In patients with peripheral artery disease undergoing major vascular surgery, the likely mechanism of PMI appears to be the hemodynamic stress related to the type and duration of surgery. NT-proBNP was a useful independent predictor of CVE and thus may serve as an important biomarker of cardiovascular fitness for surgery.

[In-hospital Myocardial Infarction: Scale of the Problem]

All cases of acute myocardial infarction (AMI) can be divided into outpatient-onset AMI and in-hospital-onset AMI depending on the place and circumstances of their development. In this review we consider the problem of in-hospital AMI. Special attention is paid to specific features of its clinical manifestations and the scale of the clinical problem. Possible causes of difficulties in the diagnosis and treatment of this condition are presented in comparison with those in patients with outpatient-onset AMI.

Myocardial injury after non-cardiac surgery: diagnosis and management

Myocardial injury after non-cardiac surgery (MINS) is due to myocardial ischaemia (i.e. supply-demand mismatch or thrombus) and is associated with an increased risk of mortality and major vascular complications at 30 days and up to 2 years after non-cardiac surgery. The diagnostic criteria for MINS includes an elevated post-operative troponin measurement judged as resulting from myocardial ischaemia (i.e. no evidence of a non-ischaemic aetiology), during or within 30 days after non-cardiac surgery, and without the requirement of an ischaemic feature (e.g. ischaemic symptom, ischaemic electrocardiography finding). For patients with MINS who are not at high risk of bleeding, physicians should consider initiating dabigatran 110 mg twice daily and low-dose aspirin. Physicians should also consider initiating statin therapy in patients with MINS. Most MINS patients should only be referred to cardiac catheterization if they demonstrate recurrent instability (e.g. cardiac ischaemia, heart failure). Patients ≥65 years of age or with known atherosclerotic disease should have troponin measurements on days 1, 2, and 3 after surgery while the patient is in hospital to avoid missing &gt;90% of MINS and the opportunity to initiate secondary prophylactic measures and follow-up.

Etiology of Acute Coronary Syndrome after Noncardiac Surgery

BACKGROUND

The objective of this investigation was to determine the etiology of perioperative acute coronary syndrome with a particular emphasis on thrombosis versus demand ischemia.

METHODS

In this retrospective cohort study, adult patients were identified who underwent coronary angiography for acute coronary syndrome within 30 days of noncardiac surgery at a major tertiary hospital between January 2008 and July 2015. Angiograms were independently reviewed by two interventional cardiologists who were blinded to clinical data and outcomes. Acute coronary syndrome was classified as ST-elevation myocardial infarction, non-ST-elevation myocardial infarction, or unstable angina; myocardial infarctions were adjudicated as type 1 (plaque rupture), type 2 (demand ischemia), or type 4b (stent thrombosis).

RESULTS

Among 215,077 patients screened, 146 patients were identified who developed acute coronary syndrome: 117 were classified as non-ST-elevation myocardial infarction (80.1%); 21 (14.4%) were classified as ST-elevation myocardial infarction, and 8 (5.5%) were classified as unstable angina. After coronary angiography, most events were adjudicated as demand ischemia (type 2 myocardial infarction, n = 106, 72.6%) compared to acute coronary thrombosis (type 1 myocardial infarction, n = 37, 25.3%) and stent thrombosis (type 4B, n = 3, 2.1%). Absent or only mild, nonobstructive coronary artery disease was found in 39 patients (26.7%). In 14 patients (9.6%), acute coronary syndrome was likely due to stress-induced cardiomyopathy. Aggregate 30-day and 1-yr mortality rates were 7 and 14%, respectively.

CONCLUSIONS

The dominant mechanism of perioperative acute coronary syndrome in our cohort was demand ischemia. A subset of patients had no evidence of obstructive coronary artery disease, but findings were consistent with stress-induced cardiomyopathy.

Off-Pump Coronary Artery Bypass Grafting with Mini-Sternotomy in the Treatment of Triple-Vessel Coronary Artery Disease

We have developed off-pump coronary artery bypass approach with lower distal mini-sternotomy (TM-OPCAB) for multivessel coronary revascularization. The aim of this retrospective study is to provide evidence for the feasibility and safety of this technique in the treatment of triple-vessel diseases.Two hundred eighty-eight patients with triple-vessel coronary artery disease who underwent TM-OPCAB or standard off-pump coronary artery bypass surgery (S-OPCAB) were included in this study after propensity-score matching. We retrospectively reviewed the clinical data of all patients and compared their demographic data, intra- and perioperative details, as well as short-term and long-term outcomes.TM-OPCAB resulted in significantly shorter periods of time on ventilation (P = 0.0222), shorter postoperative in-hospital stays (P < 0.0001), and lower blood transfusion rates (P = 0.0013) than S-OPCAB. Transit-time flow measurement showed there was no significant difference in postoperative graft patency between both groups. Within the 30-day post-surgical period, no death or occurrence of stroke was observed in patients undergoing TM-OPCAB or S-OPCAB. After an average of 35 months of follow-up, Kaplan-Meier survival analysis indicated that overall survival and the percentage of patients freed from major adverse cardiac and cerebrovascular events were similar between both groups. Additionally, the rate of repeat revascularization was slightly lower in the TM-OPCAB group (1.4%) than in the S-OPCAB group (2.2%), although there was no statistical difference noted.Our findings suggest that TM-OPCAB is technically feasible and safe for use in revascularization procedures in patients with triple-vessel diseases.

Associations Between Cardiac Troponin, Mechanism of Myocardial Injury, and Long-Term Mortality After Noncardiac Vascular Surgery

BACKGROUND

The time-sensitive hazard of perioperative cardiac troponin T (cTnT) elevation and whether long-term mortality differs by mechanism of myocardial injury are poorly understood.

METHODS AND RESULTS

In this observational study of 12 882 patients who underwent noncardiac vascular surgery, patients were assessed for cTnT sampling within 96 hours postoperatively. Mortality out to 5-years was stratified by cTnT level and mechanism of myocardial injury. During a median follow-up of 26.9 months, there were 2149 (16.7%) deaths. By multivariable Cox proportional hazards analysis, there was a graded increase in mortality with any detectable cTnT compared to <0.01 ng/mL; cTnT 0.01 to 0.029 ng/mL hazard ratio (HR) 1.54 (95% CI 1.18-2.00, P=0.002), 0.03 to 0.099 ng/mL HR 1.86 (95% CI 1.49-2.31, P<0.001), 0.10 to 0.399 ng/mL HR 1.83 (95% CI 1.46-2.31, P<0.001), ≥0.40 ng/mL HR 2.62 (95% CI 2.06-3.32, P<0.001). Mortality for each mechanism of injury was greater than for patients with normal cTnT; baseline cTnT elevation HR 1.71 (95% CI 1.31-2.24; P<0.001), Type 2 myocardial infarction HR 1.88 (95% CI 1.57-2.24; P<0.001), Type 1 MI HR 2.56 (95% CI 2.56, 1.82-3.60; P<0.001). On Kaplan-Meier analysis, long-term survival did not differ between mechanisms. The hazard of mortality was greatest within the first 10 months postsurgery. Consistent results were obtained in confirmatory propensity-score matched analyses.

CONCLUSIONS

Any detectable cTnT ≥0.01 ng/mL is associated with increased long-term mortality after vascular surgery. This risk is greatest within the first 10 months postoperatively. While short-term mortality is greatest with Type 1 myocardial infarction, long-term mortality appears independent of the mechanism of injury.

Role of prophylactic coronary revascularisation in improving cardiovascular outcomes during non-cardiac surgery: A narrative review

Coronary revascularisation has been a topic of debate for over three decades in patients undergoing high-risk non-cardiac surgery. The paradigm shifted from routine coronary angiography toward stress test guided decision-making based on larger randomised trials. However, this paradigm is challenged by relatively newer data where routine coronary angiography and revascularisation is shown to improve perioperative cardiovascular outcomes. We review major studies performed over a long period including more contemporary data with regard to the 2014 American College of Cardiology/American Heart Association as well as 2014 European Society of Cardiology guideline on perioperative cardiovascular evaluation of patients undergoing non-cardiac surgery.

Coronary Angiography and Revascularization Prior to Noncardiac Surgery

OPINION STATEMENT

The role of coronary angiography and revascularization, including percutaneous coronary intervention (PCI) prior to noncardiac surgery remains poorly defined. The goal of preoperative angiography and PCI is improved risk stratification and ideally risk reduction of postoperative cardiovascular events, such as myocardial infarction (MI). By current guidelines, these procedures should be performed sparingly in high-risk stable coronary artery disease (CAD) patients and routinely in patients with acute coronary syndrome (ACS). Anatomic assessment of CAD by routine invasive angiography is discouraged, although noninvasive assessment may soon be possible. As prior trials have failed to show a clear benefit in outcomes, PCI should only be considered in patients with high-risk anatomic features. The ideal management of other anatomic disease discovered by angiography is currently unknown. Limited registry data suggest that PCI is used more frequently than recommended, although the features of these procedures remain poorly elaborated. In patients who do undergo preoperative PCI, careful attention must be paid to patient-specific factors including the nature and urgency of surgery and duration of dual antiplatelet therapy. In summary, substantial evidence gaps warrant further research in this important area.

Prognostic capabilities of coronary computed tomographic angiography before non-cardiac surgery: prospective cohort study

OBJECTIVES

To determine if coronary computed tomographic angiography enhances prediction of perioperative risk in patients before non-cardiac surgery and to assess the preoperative coronary anatomy in patients who experience a myocardial infarction after non-cardiac surgery.

DESIGN

Prospective cohort study.

SETTING

12 centers in eight countries.

PARTICIPANTS

955 patients with, or at risk of, atherosclerotic disease who underwent non-cardiac surgery.

INTERVENTIONS

Coronary computed tomographic angiography was performed preoperatively; clinicians were blinded to the results unless left main disease was suspected. Results were classified as normal, non-obstructive (<50% stenosis), obstructive (one or two vessels with ≥ 50% stenosis), or extensive obstructive (≥ 50% stenosis in two vessels including the proximal left anterior descending artery, three vessels, or left main).

MAIN OUTCOME MEASURE

Composite of cardiovascular death and non-fatal myocardial infarction within 30 days after surgery (primary outcome). This was the dependent variable in Cox regression. The independent variables were scores on the revised cardiac risk index and findings on coronary computed tomographic angiography.

RESULTS

The primary outcome occurred in 74 patients (8%). The model that included both scores on the revised cardiac risk index and findings on coronary computed tomographic angiography showed that coronary computed tomographic angiography provided independent prognostic information (P=0.014; C index=0.66). The adjusted hazard ratios were 1.51 (95% confidence interval 0.45 to 5.10) for non-obstructive disease; 2.05 (0.62 to 6.74) for obstructive disease; and 3.76 (1.12 to 12.62) for extensive obstructive disease. For the model with coronary computed tomographic angiography compared with the model based on the revised cardiac risk index alone, with 30 day risk categories of <5%, 5-15%, and >15% for the primary outcome, the results of risk reclassification indicate that in a sample of 1000 patients that coronary computed tomographic angiography would have resulted appropriately in 17 net patients receiving a higher risk estimation among the 77 patients who would have experienced the primary outcome (P<0.001). Coronary computed tomographic angiography, however, would have resulted inappropriately in 98 net patients receiving a higher risk estimation, among the 923 patients who would not have experienced the primary outcome (P<0.001). Among patients who had a perioperative myocardial infarction, preoperative coronary anatomy showed extensive obstructive disease in 31% (22/71), obstructive disease in 41% (29/71), non-obstructive disease in 24% (17/71), and normal findings in 4% (3/71).

CONCLUSIONS

Though findings on coronary computed tomographic angiography can improve estimation of risk for patients who will experience perioperative cardiovascular death or myocardial infarction, findings are more than five times as likely to lead to an inappropriate overestimation of risk among patients who will not experience these outcomes. Perioperative myocardial infarction occurs across the spectrum of coronary artery disease, suggesting that there could be several pathophysiologic mechanisms.