Risk Of Postoperative Myocardial Infarction Research Articles

Postoperative myocardial injury after major head and neck cancer surgery

Background/objective: This narrative review aims to assess the causes and evaluate the scientific evidence concerning the increased risk of postoperative myocardial infarction (PMI) in patients undergoing major head and neck surgery. Method: A comprehensive review of literature was conducted and findings from clinical trials, meta-analysis as well as observational studies were incorporated to explore the risk factors associated with PMI after a major head and neck surgery. Preoperative risk factors, appropriate diagnostic plans, biomarkers, risk stratification strategies, and treatment options were also assessed. Result: The review highlights that patients undergoing head and neck surgery are at a significant risk of developing PMI primarily due to surgical trauma, anesthesia, and the extensive nature of head and neck surgeries. However, pre-existing conditions like renal insufficiency, cerebrovascular diseases, and diabetes may also exacerbate this risk. Moreover, ECG and regular observation of troponin has proven to be successful in detecting PMI, which can be easily masked due to its ambiguous symptoms in postoperative patients that are receiving pain reducing medications. Once diagnosed, PMI is treated with standard medication for myocardial infarction, however, more emphasis has been put on its timely diagnosis through routine troponin testing. Conclusion: Head and neck cancers are prevalent in developing nations such as Pakistan where the use of tobacco is widespread. As a result of such aggressive cancer, patients may undergo surgery, which places them at a risk of developing PMI. This can be avoided through routine troponin testing which still requires further research on localized patient population considering the physiologic differences.

The Significance of Equipment Availability and Anesthesia Educational Conferences to Decision-Making for EKG Lead V5 Abnormalities.

Introduction To predict postoperative myocardial infarction rates in patients who undergo noncardiac surgery, the Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management recommends assessment of brain natriuretic peptide (BNP) in certain patients. Serial troponins are measured if the BNP level is elevated. In certain cases, Revised Cardiac Risk Index (RCRI) alone does not perform well, for example, during vascular surgery. Cardiac events occur in 20% of all vascular surgery patients. The odds ratio for such events is 9.2 if ST segments were depressed by 1 mm intraoperatively (relative to the PR interval) within the first 48 hours postoperatively. Increasing the number of cables and pads from three to five for electrocardiogram (EKG) increases the sensitivity from around 30% to over 80% for ischemic events relative to a formal EKG stress test, and then the monitor continuously displays not only lead II but also lead V5. Methods Our hypothesis was that raising awareness about diagnostic and therapeutic options to reduce the risk of postoperative myocardial infarction would increase the use of five pads. We conducted open-ended surveys at six hospitals to assess the reasons for choosing three pads. In our university hospital practice, we measured a cross-sectional incidence of using three pads before and, once again, a month after an intervention during a single morning. Several resident conferences encouraged the use of five pads. Education included weekly lectures and informal discussions with other staff during surgery, demonstrating that using five pads allows interrogation of an entire 12-lead EKG. In comparison, three pads only allow viewing three leads. Results At baseline, only three pads were available in 96% of our 23 operating rooms. Five cables were available in eight of those surgeries, but two were taped off to the side. Surveys unveiled scarcity of equipment and, more importantly, disempowerment (i.e., knowing how to diagnose or when to treat ischemia). After several conferences, the prevalence of equipment availability of only three pads fell to 47%. Conclusions Education enumerated details of recognizing ischemic configurations of ST depression. Next, education revealed methods to interrupt the progression of ischemia to infarction such as elevated blood pressure and hematocrit, reducing heart rate, and calling a cardiology consultant if the anesthesiologist wishes to draw serial troponins. Barriers to implementing an enhanced recovery after surgery (ERAS) pathway began with a need for more access to manage stress tests or optimize blood pressure medications after a preoperative anesthesia evaluation. The intraoperative barrier was knowing what to do if ST depression occurs. Therefore, we began raising awareness by encouraging the addition of an element of a future ERAS pathway, adding a cost of only $1 to monitor lead V5. Future ERAS pathways can include preoperative stress tests and consults, as found in published guidelines.

Cardiovascular Disease in Total Knee Arthroplasty: An Analysis of Hospital Outcomes, Complications, and Mortality.

Cardiovascular comorbidities have been identified as a significant risk factor for adverse outcomes following surgery. The purpose of this study was to investigate its prevalence and impact on postoperative outcomes, hospital metrics, and mortality in patients undergoing total knee arthroplasty (TKA). Our hypothesis was that patients with cardiovascular comorbidities would have worse outcomes, greater postoperative complication rates, and increased mortality compared to patients without cardiovascular disease. In this retrospective study, data from the National Inpatient Sample database from 2011 to 2020 were queried for patients who underwent TKA with preexisting cardiac comorbidities, including congestive heart failure (CHF), coronary artery disease (CAD), valvular dysfunction, and arrhythmia. Multivariate logistic regression analyses compared hospital metrics (length of stay, costs, and adverse discharge disposition), postoperative complications, and mortality rates while adjusting for demographic and clinical variables. All statistical analyses were performed using R studio 4.2.2 and Stata MP 17 and 18 with Python package. A total of 385,585 patients were identified. Those with preexisting CHF, CAD, valvular dysfunction, or arrhythmias were found to be older and at higher risk of adverse outcomes, including prolonged length of stay, increased hospital charges, and increased mortality (p < 0.001). Additionally, all preexisting cardiac diagnoses led to an increased risk of postoperative myocardial infarction, acute kidney injury (AKI), and need for transfusion (p < 0.001). The presence of valvular dysfunction, arrhythmia, or CHF was associated with an increased risk of thromboembolic events (p < 0.001). The presence of CAD and valvular dysfunction was associated with an increased risk of urologic infection (p < 0.001). This study demonstrated that CHF, CAD, valvular dysfunction, and arrhythmia are prevalent among TKA patients and associated with worse hospital metrics, higher risk of perioperative complications, and increased mortality. As our use of TKA rises, a lower threshold for preoperative cardiology referral in older individuals and early preoperative counseling/intervention in those with known cardiac disease may be necessary to reduce adverse outcomes.

Geriatric approach to the treatment of senile patients with colorectal cancer

Introduction. The lack of consensus guidelines for the treatment of colorectal cancer (CRC) in senile patients, the high incidence of early postoperative complications after radical surgery caused the search for the most optimal approach to the management of this category of patients.The aim is to introduce a geriatric approach to the treatment of colorectal cancer in senile patients, reduce the incidence of Clavien–Dindo grade 4 early postoperative complications.Materials and methods. 190 senile patients who underwent radical surgery with D3 lymphadenectomy with stage II and III colorectal cancer were enrolled in the study. They were divided into two groups: the control group included 100 patients who underwent standard treatment, the study group included 90 patients, to whom the geriatric approach with a comprehensive geriatric assessment (CGA) and subsequent pre-rehabilitation was applied. A comparative intergroup analysis was performed on the basis of obtained data.Results. The study group differed from the control group in higher polymorbidity and high operational and anesthetic risk (p &lt;0.001). Implementation of geriatric pre-rehabilitation with due account for CGA results and correction of polymorbidity improved chances of providing surgical care using laparoscopic and robotic technologies. The frequency of intraoperative blood transfusion and prolonged mechanical ventilation in the study group was reduced (p &lt;0.001 and p = 0.009, respectively). Predictors that increase the chances of developing acute postoperative myocardial infarction were identified. They included the patient’s male gender (p = 0.004), redo surgery after development of early postoperative complications (p = 0.043), prolonged mechanical ventilation (p = 0.052), increased length of stay in the intensive care unit (p = 0.011), and comorbidity (p = 0.022). The introduction of the geriatric approach made it possible to reduce the risk of postoperative myocardial infarction by 17.86 times (p = 0.007).Conclusion. The geriatric approach to the senile patients with colorectal cancer makes it possible to expand the indications for radical treatment in severe polymorbidity and senile asthenia, as well as to reduce the incidence of early postoperative complications.

Postoperative mortality in hip fracture patients stratified by the Revised Cardiac Risk Index: a Swedish nationwide retrospective cohort study

ObjectivesThe Revised Cardiac Risk Index (RCRI) is a tool that can be used to evaluate the 30-day risk of postoperative myocardial infarction, cardiac arrest and mortality. This study aims to...

A medical history of arterial thrombosis is a strong predictor of post-operative myocardial infarction and stroke in patients with hip fractures—a nationwide cohort study

Hip fractures lead to a substantial burden of disease and mortality among the elderly. Myocardial infarction (MI) and stroke are serious and overlooked complications, and their impact on mortality and morbidity may be underestimated. We investigated; 90-day absolute risk of stroke and MI following hip fracture surgery, and ii) anamnestic risk factors associated with elevated risk of postoperative MI and stroke. All Danish patients aged ≥60 undergoing first time hip fracture surgery in 2000-2017 were identified. Outcomes were MI or stroke 90 days after surgery. We performed gender-stratified cumulative incidence functions and multivariate Cox regression models adjusted for age and comorbidities. 124,660 patients were included. Incidence of MI was 2.2% and 1.3%, and incidence of stroke was 3.5% and 2.5%, in men and women, respectively. The most important risk factor for MI and stroke was a previous event. Hazard ratio (HR) of MI associated with previous MI was 2.43 (95% Confidence Interval (CI) 2.02-2.92) in men and 2.65 (95% CI 2.23-3.16) in women, while the HR of stroke associated with previous stroke was 4.17 (95% CI 3.73-4.67) and 3.73 (95% CI 3.43-4.08), respectively. Other risk factors of MI were; sex, age, and a history of heart failure, hypertension, peripheral artery disease or diabetes. For postoperative stroke; sex age, and atrial fibrillation were important risk factors. MI and stroke after hip fractures are overlooked and serious complications. Persons with elevated risk can be identified at admission, based on their medical history.

TransCarotid Revascularization With Dynamic Flow Reversal Versus Carotid Endarterectomy in the Vascular Quality Initiative Surveillance Project.

To compare the outcomes of TCAR with flow reversal to the gold standard CEA using data from the Society for Vascular Surgery Vascular Quality Initiative TCAR Surveillance Project. TCAR is a novel minimally invasive procedure for carotid revascularization in high-risk patients that is associated with significantly lower stroke rates compared with carotid artery stenting via the transfemoral approach. Patients in the United States and Canada who underwent TCAR and CEA for carotid artery stenosis (2016-2019) were included. Propensity scores were calculated based on baseline clinical variables and used to match patients in the 2 treatment groups (n = 6384 each). The primary endpoint was the combined outcome of perioperative stroke and/or death. No significant differences were observed between TCAR and CEA in terms of in-hospital stroke/death [TCAR, 1.6% vs CEA, 1.6%, RR (95% CI): 1.01 (0.77-1.33), P = 0.945], stroke [1.4% vs 1.4%, RR (95% CI): 1.02 (0.76-1.37), P = 0.881], or death [0.4% vs 0.3%, RR (95% CI): 1.14 (0.64-2.02), P = 0.662]. Compared to CEA, TCAR was associated with lower rates of in-hospital myocardial infarction [0.5% vs 0.9%, RR (95% CI): 0.53 (0.35-0.83), P = 0.005], cranial nerve injury [0.4% vs 2.7%, RR (95% CI): 0.14 (0.08-0.23), P < 0.001], and post-procedural hypertension [13% vs 18.8%, RR (95% CI): 0.69 (0.63-0.76), P < 0.001]. They were also less likely to stay in the hospital for more than 1 day [26.4% vs 30.1%, RR (95% CI): 0.88 (0.82-0.94), P < 0.001]. No significant interaction was observed between procedure and symptomatic status in predicting postoperative outcomes. At 1 year, the incidence of ipsilateral stroke or death was similar between the 2 groups [HR (95% CI): 1.09 (0.87-1.36), P = 0.44]. This propensity-score matched analysis demonstrated significant reduction in the risk of postoperative myocardial infarction and cranial nerve injury after TCAR compared to CEA, with no differences in the rates of stroke/death.

Gender Disparities in Presentation, Treatment, and Outcomes of Critical Limb Ischemia

Women with peripheral artery disease (PAD) experience higher rates of functional decline and may have worse clinical outcomes after invasive treatment for PAD compared to men. Despite this, women remain under-represented in contemporary PAD studies. We aim to use National Surgical Quality Improvement Program data to better understand differences in presentation, treatment, and short-term outcomes for women compared to men undergoing lower extremity (LE) revascularization for critical limb ischemia (CLI). We included 2018 patients. The National Surgical Quality Improvement Program database includes 30-day outcomes for inpatient operations at participating hospitals. Descriptive statistics and multivariable analyses were performed. There were a total of 32,902 LE interventions, of which 22,111 (67%) were for patients with CLI (rest pain or tissue loss). Women were significantly more likely to have CLI on presentation (71% vs 65%; P < .001) compared to men. In the cohort of patients undergoing LE intervention for CLI, women were more likely to be older (mean, 70 ± 12 years vs 68 ± 11 years; P < .001), black (25% vs 18%; P < .001), and hypertensive (86% vs 82%; P < .001), and less likely to be smokers (31% vs 38%; P < .001), on a statin medication (69% vs 71%; P < .001), or functionally independent (84% vs 89%; P < .001). Women were more likely to have a preoperative ankle-brachial index of <0.4 (20% vs 16%; P < .001) compared to men (Table I). Women with CLI were more likely to undergo endovascular intervention compared to men (44% vs 38%; P < .001) and were less likely to have distal/tibial artery revascularization (Table I). Women who underwent open operations had a higher risk of surgical site infection (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.3-1.6) and 30-day reintervention (OR, 1.2; 95% CI, 1.01-1.4) compared to men (Table II). Men with CLI who underwent endovascular intervention were more likely to undergo a major amputation within 30 days compared to women (OR, 1.3; 95% CI, 1.1-1.6). Overall, women had a higher risk of postoperative myocardial infarction (MI) and death compared to men (OR, 1.2; 95% CI, 1.02-1.4). Women undergoing LE revascularization for CLI are older, present with more advanced ischemia, and are more likely to undergo endovascular intervention compared to men. Despite increased use of less invasive strategies to treat CLI, women have higher rates of 30-day death and MI. Women with cardiovascular risk factors may benefit from more aggressive screening and medical treatment for PAD in order to mitigate the negative consequences of CLI.Table IBaseline patient and operative characteristicsFemale n = 8441Male n = 13,670P valueAge in years, mean (SD)70 (12)68 (11)<.001Race<.001 White4964 (59%)8944 (65%) Black or African American2078 (25%)2416 (18%) Other/unknown1399 (17%)2310 (17%)Diabetes4536 (54%)7619 (56%).004Hypertension7238 (86%)11,262 (82%)<.001Dialysis828 (10%)1450 (11%).06Smoking2635 (31%)5121 (38%)<.001Preoperative aspirin6804 (81%)10,974 (81%).55Preoperative statin5763 (69%)9684 (71%)<.001Preoperative beta-blocker5104 (61%)8369 (62%).23Preoperative function status<.001 Independent7122 (84%)12,196 (89%) Partially dependent1148 (14%)1256 (9%) Totally dependent118 (1%)134 (1%)Preoperative ABI <0.41698 (20%)2239 (16%)<.001Prior ipsilateral intervention3401 (40.3%)5146 (37.6%)<.001Open Intervention4717 (56%)8531 (62%)<.001 Operation type<.001Femoral popliteal bypass2623 (56%)3997 (47%)Femoral distal bypass1521 (32%)3152 (37%)Popliteal distal bypass435 (9%)1060 (13%)Femoral endarterectomy51 (1%)105 (1%) Conduit<.001Single segment vein2309 (49%)4411 (52%)Prosthetic/spliced vein2270 (48%)3798 (45%)Endovascular intervention3724 (44%)5139 (38%)<.001 Operation type<.001Femoral/popliteal angioplasty/stent2831 (77%)3362 (66%)Tibial angioplasty/stent867 (23%)1739 (34%)Operative time in minutes, mean (SD)186 (117)200 (121)<.001ABI, Ankle-brachial index; SD, standard deviation. Open table in a new tab Table IIThirty-day outcomesOpenEndovascularFemale n = 4717Male n = 8531P valueFemale n = 3724Male n = 5139P valueMyocardial infarction183 (3.9%)287 (3.3%)0.1284 (2.3%)92 (1.8%).12Surgical site infection496 (10.5%)639 (7.5%)<.00151 (1.4%)61 (1.2%).45Reintervention290 (6.1%)449 (5.3%)0.034152 (4.1%)258 (5.0%).038Major amputation209 (4.4%)375 (4.4%)0.93162 (4.4%)296 (5.8%).003Death77 (1.6%)119 (1.4%)0.2855 (1.5%)69 (1.3%).60 Open table in a new tab

Association of High Mortality With Postoperative Myocardial Infarction After Major Vascular Surgery Despite Use of Evidence-Based Therapies

Patients undergoing vascular surgery are at high risk of postoperative myocardial infarction (POMI). Postoperative myocardial infarction is independently associated with significant risk of in-hospital mortality. To examine the association of patient and procedural characteristics with the risk of POMI after vascular surgery and determine the association of evidence-based therapies with longer-term outcomes. A retrospective cohort study of prospectively collected data within a statewide quality improvement collaborative database between January 2012 and December 2017. Patient demographics, comorbid conditions, and perioperative medications were captured. Patients were grouped according to occurrence of POMI. Univariate analysis and logistic regression were used to identify factors associated with POMI. The collaborative collects data from private and academic hospitals in Michigan. Patients undergoing major vascular surgery, defined as endovascular aortic aneurysm repair, open abdominal aortic aneurysm, peripheral bypass, carotid endarterectomy, or carotid artery stenting were included. Analysis began December 2018. The presence of a POMI and 1-year mortality. Of 26 231 patients identified, 16 989 (65.8%) were men and the overall mean (SD) age was 69.35 (9.89) years. A total of 410 individuals (1.6%) experienced a POMI. Factors associated with higher rates of POMI were age (odds ratio [OR], 1.032 [95% CI, 1.019-1.045]; P < .001), diabetes (OR, 1.514 [95% CI, 1.201-1.907]; P < .001), congestive heart failure (OR, 1.519 [95% CI, 1.163-1.983]; P = .002), valvular disease (OR, 1.447 [95% CI, 1.024-2.046]; P = .04), coronary artery disease (OR, 1.381 [95% CI, 1.058-1.803]; P = .02), and preoperative P2Y12 antagonist use (OR, 1.37 [95% CI, 1.08-1.725]; P = .009). Procedurally, open abdominal aortic aneurysm (OR, 4.53 [95% CI, 2.73-7.517]; P < .001) and peripheral bypass (OR, 2.375 [95% CI, 1.818-3.102]; P < .001) were associated with the highest risk of POMI. After POMI, patients were discharged and received evidence-based therapy with high fidelity, including β-blockade (296 [82.7%]) and antiplatelet therapy (336 [95.7%]). A high portion of patients with POMI were dead at 1 year compared with patients without POMI (113 [37.42%] vs 993 [5.05%]; χ2 = 589.3; P < .001). Despite high rates of discharge with evidence-based therapies, the long-term burden of POMI is substantial, with a high mortality rate in the following year. Patients with diabetes mellitus, coronary artery disease, congestive heart failure, and valvular disease warrant additional consideration in the preoperative period. Further, aggressive strategies to treat patients who experience a POMI are needed to reduce the risk of postoperative mortality.

P6172Management of silent myocardial ischemia in patients with peripheral arterial disease needing surgery

Abstract Background Patients with peripheral arterial disease (PAD) needing surgery have increased risk for post-operative myocardial infarction (MI)/death due to coexisting coronary artery disease (CAD). Coronary CT angiography (CTA)-derived fractional flow reserve (FFRCT) can reliably identify ischemia-producing coronary stenosis in patients with suspected CAD but its value in PAD patients is unknown. Purpose To determine the prevalence of silent coronary ischemia in PAD patients undergoing surgery and to assess the value of FFRCT in guiding management of patients with multisite arterial ischemia. Methods Patients admitted for elective carotid, aortic or peripheral vascular surgery with no cardiac history or CAD symptoms were enrolled in a prospective, open-label, ethics committee-approved study and underwent pre-op CTA and FFRCT evaluation with results available to treating physicians. Ischemia-producing coronary stenosis was defined as FFRCT≤0.80 distal to stenosis in &gt;2mm diameter vessels. Patient management was guided by a multidisciplinary team of cardiologists, cardiovascular surgeons and anaesthesiologists. Primary endpoint was major adverse cardiac events (MACE= cardiac death, MI, urgent revasc) at 30 days with follow up at 3,6,12 months. Results Coronary CTA and FFRCT analysis was performed in 179 consecutive patients (age 66±8 years, male 78%, hypertension 79%, diabetes 10%, dyslipidemia 31%, smoking 37%). CTA revealed extensive coronary calcification (Agatston score 995±1004, range 0–4810) and ≥50% stenosis in 64% of patients. Ischemic coronary stenosis (FFRCT≤0.80) was present in 114 patients (64%) with FFRCT ≤0.75 in 97 (54%) and multivessel ischemia in 63 (35%). Clinically indicated vascular surgery was performed as planned in 170/179 patients (95%) with cardiac anaesthesia and close monitoring and postponed in 9 patients for coronary revascularization (3) or medical/other therapy (6). There were no post-op cardiac complications. Elective coronary angiography, performed 1–3 months post surgery in 86 patients with left main, severe or multivessel ischemia, confirmed significant stenosis in each patient with revascularization in 58 patients (53 PCI and 5 CABG) including 8 for LM disease. There have been no cardiovascular deaths; 3 patients have died of lung cancer which was first discovered on CTA. One patient had peri-procedural MI at time of PCI and one had MI and urgent PCI at 6 months. MACE at 30 days=0/179, 3 months = 1/154, 6 months=2/123, 12 months=0/65. Conclusions Patients undergoing elective PAD surgery have a high prevalence (64%) of unsuspected ischemia-producing coronary stenosis. Pre-op diagnosis with CTA- FFRCT can help guide a multidisciplinary team approach with optimum medical management and staged peripheral and coronary revascularization. Favourable early results are promising and suggest the need for prospective controlled studies to define the role of coronary revascularization in PAD patients. Acknowledgement/Funding Heartflow, Inc.; Mikrotikls Ltd

Risk factors for postoperative myocardial infarct following cholecystectomy: a population-based study

BackgroundThe aim was to analyse the risk for myocardial infarction (MI) after cholecystectomy. MethodsThe study is based on data from the Swedish Register for Gallstone Surgery (GallRiks) 2006–2014. The cohort was cross-linked with the Swedish Patient Register. Standardised incidence ratio (SIR) was calculated by dividing the observed incidence of MI within 30 days after surgery with the expected incidence of the background population. ResultsAltogether 94,577 procedures were included. MI within 30 days postoperatively (30d-po) were registered in 87 cases (0.09%, SIR for MI 3.03; 95% CI 2.43–3.74). MI occurred more often in men (0.15% vs 0.06%), after open surgery (0.34% vs 0.04%), was age related (age >50 years OR 4.05 > 75 years OR 15.70) and occurred more frequently amongst those with gallstone complications and high ASA score (ASA 1; 0.02%, 2; 0.08%, ≥3; 0,64%). The risk for MI within 30d-po was 52.8% if the patient had suffered an infarct within 8 weeks preoperatively. Laparoscopy converted to open and primarily open surgery were independent risk factors (OR 3.05 vs 2.19). The mortality in the group with 30d-po MI was 11.5% vs 0.02%. ConclusionDelaying elective cholecystectomy for at least 8 weeks after a recent MI reduces the risk for postoperative MI.

Web Exclusive. Annals Consult Guys - Low Risk for Postoperative Myocardial Infarction: What Do We Really Know?

Web Exclusive. Annals Consult Guys - Low Risk for Postoperative Myocardial Infarction: What Do We Really Know?

Annals for Educators - 15 January 2019.

Annals for Educators - 15 January 2019.

Prediction of postoperative myocardial infarction after suprainguinal bypass using the Vascular Quality Initiative Cardiac Risk Index

BackgroundThe Vascular Quality Initiative (VQI) Cardiac Risk Index (CRI) was developed to estimate the risk of postoperative myocardial infarction (POMI) for noncardiac vascular procedures. Whereas suprainguinal bypass carried the second highest odds of POMI, the performance of the all-procedure model declined when it was applied to the suprainguinal subset. We sought to improve the VQI CRI for application in this high-risk group undergoing open revascularization for aortoiliac occlusive disease. MethodsThe VQI Suprainguinal Bypass Registry was queried for elective procedures performed between January 2010 and March 2017. Logistic regression was used to create a model for estimating the risk of in-hospital POMI with preoperative variables including demographics, comorbidities, and planned inflow source. After adjustment for overfitting, internal validation was performed using both bootstrapping and 10-fold cross-validation methods. ResultsAmong 8157 procedures, the incidence of POMI was 3.2% (n = 258). After bootstrapping variable selection, age, graft inflow, preoperative stress test, American Society of Anesthesiologists class, indication for procedure, and coronary artery disease were chosen for inclusion as predictors in the final risk model. The final model demonstrated good discrimination (area under the curve = 0.725). On internal validation, the model discriminated well (area under the curve = 0.713), with good calibration (plot intercept = 0.0006 and slope = 1.001). Using this model, POMI risk estimates ranged from 0.6% to 30.4%. ConclusionsWhereas the incidence of POMI among all suprainguinal bypasses was 3%, model-based estimates ranged 50-fold, from 0.6% to 30.4%. This underscores the heterogeneity of this cohort and the need for patient-specific risk estimation. Although some of the strongest predictors were nonmodifiable (eg, age), the model provided specific estimates according to graft inflow and stress testing. This supraspecific VQI CRI module risk predictor may enhance preoperative counseling by influencing the decision to pursue preoperative stress testing and ultimately the type of revascularization strategy chosen.

Metabolic Syndrome Increases Risk of Postoperative Myocardial Infarction Following Percutaneous Nephrolithotomy.

Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for upper tract stone burdens greater than 2 cm. Metabolic syndrome (MetS) is a constellation of conditions (diabetes mellitus, hypertension, dyslipidemia, and obesity) and is a risk factor for nephrolithiasis. Our objective was to investigate adverse cardiovascular outcomes of PCNL in patients with comorbid MetS diagnoses. Data from the Healthcare Cost and Utilization Project State Inpatient Database for Florida and California were used to identify PCNL patients (ICD9: 55.03, 55.04) between 2007 and 2011. Patients were categorized having 0, 1-2, or 3-4 components of MetS. Postoperative myocardial infarction (MI) and inhospital mortality rate outcomes were identified. Multivariate logistic regression was used to control for patient characteristics (age, race, and primary insurance provider) and medical comorbidities. PCNL was performed on 39,868 patients, of whom 17,932 (45.0%) had no MetS conditions, 19,268 (48.3%) had 1-2 MetS conditions, and 2668 (6.7%) had 3-4 MetS conditions. With increasing MetS conditions, patients had increased incidence of postoperative MI (0: 0.6%; 1-2: 1.0%; 3-4: 1.8%, p < 0.001). On multivariate analysis, the presence of 3-4 MetS comorbidities increased the odds of a postoperative MI (1-2: odds ratio [OR] 1.2, 95% confidence interval [CI] 0.94-1.53, p = 0.147; 3-4: OR 2.2, 95% CI 1.54-3.15, p < 0.001). MetS patients have an increased risk of MI following PCNL given their pre-existing comorbidities. Routine preoperative cardiac testing may benefit this population before PCNL.

P2661Impact of major bleeding on the risk of postoperative myocardial infarction in patients undergoing off-pump coronary artery bypass grafting

P2661Impact of major bleeding on the risk of postoperative myocardial infarction in patients undergoing off-pump coronary artery bypass grafting

IP127. Risk Factors for Major Adverse Clinical Events After Carotid Endarterectomy Based on Patient Age and Symptoms

Carotid endarterectomy (CEA) is a well-established surgical procedure in the treatment of symptomatic and asymptomatic carotid atherosclerosis. We reviewed the American College of Surgeons National Surgical Quality Improvement Program database to assess which factors contribute to major adverse clinical events (MACEs) in the 30-day postoperative period. The American College of Surgeons National Surgical Quality Improvement Program database was queried among all participating institutions for CEAs performed in 2011 to 2015. Patients’ demographic data, comorbid conditions, preprocedure medication use, and operative variables were analyzed using multivariate logistic regression analysis to determine predictors of postoperative MACEs. There were 17,888 patients who underwent CEA analyzed; the patients were grouped by age (<75 and ≥75 years old) and whether they presented symptomatically (SYM) or asymptomatically (AS) before the procedure. For AS patients <75 years, the rate of stroke, myocardial infarction (MI), death, and MACEs was 1.8%, 1.6%, 0.4%, and 3.6%, respectively; for patients ≥75 years, rates were 1.7%, 2.3%, 0.7%, and 4.3%. The rate of MI was significantly higher in older patients (P = .0133). The odds of postoperative stroke was 73% higher (P < .0011) in diabetics, 57% higher (P = .0109) with American Society of Anesthesiologists (ASA) score 4 or 5, and 34% higher with operative time >2.5 hours (P = .0189). SYM patients ≥75 years had 1.1 times higher risk of postoperative stroke if they had insulin-dependent diabetes (P = .0148). Reintubation and reoperation were associated with increased risk of postoperative stroke in both age groups, whether SYM or AS (P < .0001), as well as postoperative MI (P < .0001). AS patients <75 years had higher likelihood of postoperative MI if they had history of congestive heart failure (P = .0257) and operative time >2.5 hours (P = .0033). SYM patients ≥75 years had 46% higher likelihood of postoperative MI if operative time >2.5 hours (P = .0023). Mortality was higher in AS patients <75 years with ASA score 4 or 5 (P = .0006) and those ≥75 years (P = .0072) and in patients who were reintubated (P < .0001). In SYM patients <75 years, the rate of stroke, MI, death, and MACEs was 4.8%, 1.4%, 0.9%, and 6.3%, respectively. In those ≥75 years, rates were 4.9%, 2.6%, 1.6%, and 7.8%. Older patients had higher rates of MI and MACEs (P = .001 and P= .0103). SYM patients <75 years had higher mortality if they had chronic obstructive pulmonary disease (P = .0002) and diabetes (P = .0062). SYM patients of all ages had higher mortality with postoperative stroke or MI (P < 0.0001). Patients 75 years or older are at increased risk of postoperative MI after CEA regardless of symptomatic status. Diabetes, increased operative time, and ASA score 4 or 5 were associated with higher MACE rates among all age groups.

Predictors of Myocardial Infarction after Suprainguinal Bypass Using the Vascular Quality Initiative Cardiac Risk Index

Several models have been developed to estimate the risk of postoperative myocardial infarction (POMI). The Vascular Quality Initiative (VQI) Cardiac Risk Index (CRI) was developed specifically for vascular procedures; while suprainguinal bypass carried the second highest odds of POMI, the all-procedure-based model performance declined when applied to the suprainguinal subset. We sought to refine the VQI CRI for application in this high-risk group undergoing open revascularization for aortoiliac occlusive disease.

Prognostic Significance and Clinical Utility of Intraventricular Conduction Delays on the Preoperative Electrocardiogram

The prognostic significance of the preoperative electrocardiogram (ECG), particularly intraventricular conduction delays (IVCDs), on postoperative outcomes among patients undergoing noncardiac surgery is uncertain. In a retrospective cohort, we evaluated the risk associated with preoperative IVCDs on in-hospital death and postoperative myocardial infarction (POMI). The 152,479 patients who underwent noncardiac surgery were categorized by preoperative electrocardiographic findings: normal (36.1%), left bundle branch block (LBBB, 1.2%), right bundle branch block (2.9%), nonspecific IVCD (3.3%), and any other ECG abnormality (56.5%). The primary and secondary outcomes were postoperative in-hospital mortality and POMI, respectively. In multivariable-adjusted models, compared with normal ECGs, each electrocardiographic abnormality category was associated with increased risk of postoperative death: LBBB odds ratio (OR) 1.89 (95% confidence interval [CI] 1.35 to 2.65), right bundle branch block OR 1.73 (95% CI 1.33 to 2.24), nonspecific IVCD OR 1.95 (95% CI 1.53 to 2.48), and other abnormal ECG OR 1.94 (95% CI 1.68 to 2.25). ECGs with conduction delays did not confer increased risk of postoperative death compared with other ECG abnormalities. Moreover, receiver operating characteristic analysis of models incorporating demographic and co-morbidity data demonstrated marginal additive benefit of any electrocardiographic data. Risk of POMI was not significantly increased among ECGs with conduction delays compared with both normal and other abnormal ECGs. In conclusion, patients with intraventricular conduction disease, including LBBB, on preoperative ECG are not at greater risk of postoperative in-hospital death or POMI compared with patients with other ECG abnormalities. Furthermore, any preoperative electrocardiographic abnormalities, including intraventricular delays, provide marginal clinical utility beyond demographic and clinical history for predicting postoperative in-hospital death or POMI.

Estimating risk of adverse cardiac event after vascular surgery using currently available online calculators

BackgroundThe decision to proceed with vascular surgical interventions requires evaluation of cardiac risk. Recently, several online risk calculators were created to predict outcomes and to lead to a more informed conversation between surgeons and patients. The objective of this study was to compare and further validate these online calculators with actual adverse cardiac outcomes at a single institution. MethodsAll patients from January 2011 through December 2015 undergoing carotid endarterectomy (CEA), infrainguinal lower extremity bypass, open abdominal aortic aneurysm (AAA) repair, and endovascular aneurysm repair (EVAR) on the vascular surgical service were included using the Society for Vascular Surgery Vascular Quality Initiative database at our health system. Additional information was collected through retrospective chart review. Each patient was entered through three online risk calculators: (1) the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) estimates the risk of cardiac arrest and myocardial infarction (MI); (2) the Revised Cardiac Risk Index (RCRI) estimates risk of MI, pulmonary edema, ventricular fibrillation, primary cardiac arrest, and complete heart block; and (3) the Vascular Study Group of New England (VSGNE) Cardiac Risk Index estimates risk of postoperative MI only. Observed adverse cardiac events (ACEs) were compared with expected values for each calculator using a χ2 goodness-of-fit test. Institutional Review Board exemption was obtained. ResultsA total of 856 cases were included: 350 CEAs, 210 infrainguinal bypasses, 77 open AAA repairs, and 219 EVARs. For CEA, no risk calculator showed statistically significant variation from the observed values (NSQIP, P = .45; RCRI, P = .17; VSGNE, P = .24). For infrainguinal bypass, NSQIP slightly underpredicted adverse events (P = .054), RCRI strongly underpredicted (P = .002), and VSGNE showed no difference (P = .42). For open AAA repair, NSQIP (P = .51) and VSGNE (P = .98) were adequate predictors, but RCRI strongly underpredicted the adverse events (P ≤ .0001). Finally, EVAR cardiac outcomes showed greater adverse events than predicted by all three calculators (NSQIP, P = .02; RCRI, P = .0002; and VSGNE, P = .025). Pooled data for the entire group documented that the VSGNE proved an accurate tool for prediction (P = .34), whereas ACEs were underpredicted by NSQIP (P = .0055) and RCRI (P ≤ .001). ConclusionsAlthough online cardiac risk calculators of adverse surgical events are easy to use and to reference in broad surgical decision-making, there is significant variability in their predictability at the procedure and institutional level. Our data suggest that ACEs often occur at a higher rate than expected on the basis of calculated risks profiles, thus creating a platform for future discussion about preoperative evaluation and postoperative care decision-making models.