Risk Of Perioperative Cardiac Events Research Articles

ECG changes after non-cardiac surgery: a prospective observational study in intermediate-high risk patients.

Efforts to mitigate the risk for perioperative cardiac events focus on both patient's and operation's risk and often include a preprocedural electrocardiogram (ECG). The merits of postprocedural ECG for detection of occult cardiac events occurring during surgery are unknown. We aim to explore the incidence of pre, and new postprocedural ECG pathologies in an intermediate-high risk population undergoing non-cardiac surgery. This single-center, prospective, observational study, included patients older than 18 years with at least two cardiovascular risk factors who were scheduled for non-cardiac surgery. All patients had pre, and postprocedural ECG. The ECG was analyzed and coded according to the Minnesota criteria. A multivariable logistic regression analysis was performed for indices associated with new postoperative ECG pathologies. A total of 217 patients were enrolled. Preoperative pathologic ECG changes were recorded in 62.2% of the patients. Postoperatively, new ECG pathologies were documented in 49.8% of patients, most commonly T-wave changes (36.4% of changes). Pathologic ECG changes at baseline (OR 3.15, 95% CI [1.61-6.17]; P<0.01), diabetes (OR 1.93, 95% CI [1.02-3.64]; P=0.04), history of ischemic heart disease (OR 2.14, 95% CI [1.03-4.47]; P=0.04), higher volumes of fluid replacement (OR 1.70, 95% CI [1.10-2.61]; P=0.01) and higher levels of preoperative hemoglobin (OR 1.24, 95% CI [1.04-1.47]; P=0.01) were all independently associated with postoperative ECG changes. Pre-, but most importantly, postoperative ECG changes are common in intermediate-high risk surgical patients. Postoperative ECG may be valuable to disclose silent cardiovascular events that occurred during surgery.

Medical use of cocaine and perioperative morbidity following sinonasal surgery-A population study.

Topical cocaine is favoured by many surgeons for sinonasal surgery due to its superior vasoconstrictive and anesthetic properties. However, historical reports suggesting cocaine is associated with an increased risk of cardiac events have led many surgeons to turn to alternative topical medications. The objective of this study was to determine whether cocaine use during sinonasal surgery is associated with an increased risk of perioperative cardiac events and death. We conducted a population-based analysis of patients undergoing sinonasal surgery from 2009-2016 using linked administrative health care data sets in Ontario, Canada. We compared patients treated at institutions that primarily use topical cocaine (exposed group) to those treated at institutions that do not use cocaine (unexposed group). Our primary outcome was a composite of major cardiac events or all-cause mortality within 48 hours of surgery. Due to low event rates, the outcome was compared using a Fisher's exact test. Of 10,549 patients who were included in the study, 27.4% were treated at an institution that uses topical cocaine. The rate of the composite of perioperative major cardiac event or all-cause mortality within 48 hours of surgery in the exposed and unexposed groups was, ≤0.2% and 0 (p-value>0.05), respectively. In this large real-world cohort of patients undergoing sinonasal surgery, there does not appear to be any significant increased risk of morbidity or mortality associated with cocaine use. These findings have important implications for surgeons performing this procedure.

Beta Blocker Use Increases The Risk of Perioperative Cardiac Events in Liver Transplant Patients

Beta Blocker Use Increases The Risk of Perioperative Cardiac Events in Liver Transplant Patients

Preoperative Midregional Pro-Adrenomedullin and High-Sensitivity Troponin T Predict Perioperative Cardiovascular Events in Noncardiac Surgery

Objective: We evaluated the utility of preoperative midregional (MR) pro-adrenomedullin (proADM) and cardiac troponin T (TnT) for improved detection of patients at high risk for perioperative cardiac events and mortality after major noncardiac surgery. Subjects and Methods: This prospective, single-center, observational study enrolled 79 patients undergoing major noncardiac surgery. After initial clinical assessment (clinical history, physical examination, echocardiogram, blood tests, and chest X-ray), MR-proADM and high-sensitivity TnT (hsTnT) were measured within 48 h prior to surgery by immunoluminometric and electrochemiluminescence immunoassay. Patients were followed by the consulting physician until discharge or up to 14 days in the hospital after surgery. Perioperative cardiac events included myocardial infarction and development or aggravation of congestive heart failure. Data were compared between patients who developed target events and event-free patients. Results: Within 14 days of monitoring, 14 patients (17.72%) developed target events: 9 (11.39%) died and 5 (6.33%) developed cardiovascular events. The average age of the patients was 71.29 ± 6.62 years (range: 55–87). Sex, age, and hsTnT did not significantly differ between groups. MR- proADM concentration was higher in deceased patients (p = 0.01). The upper quartile of MR-proADM was associated with a fatal outcome (66.7 vs. 20.0%, p < 0.01) and with cardiovascular events (64.3 vs. 16.9%, p < 0.01). MR-proADM above the cutoff value (≥0.85) was associated with a fatal outcome (88.9 vs. 20.0%, p < 0.01) and cardiovascular events (71.4 vs. 28.6%, p < 0.01); this association was not observed for hsTnT. Conclusion: Preoperative measurement of MR-proADM provides useful information for perioperative cardiac events in high-risk patients scheduled for noncardiac surgery.

Preoperative Prevalence of J-Wave Syndrome Electrocardiographic Patterns and Their Association With Perioperative Cardiac Events.

To evaluate the preoperative prevalence of each type of J-wave syndrome electrocardiographic pattern and its association with perioperative cardiac events. Retrospective study. Single hospital university study. The study evaluated 930 patients who underwent gynecologic, abdominal, neurosurgical, orthopedic, and urologic surgeries. Preoperative standard 12-lead electrocardiogram (ECG) monitoring was performed, and each type of J-wave syndrome ECG pattern-types 1, 2, and 3 and Brugada syndrome-type-was evaluated. Incidence of perioperative cardiac events was investigated up to 1 year postoperatively using an electronic medical record system. Data from 789 patients were included in the final study. Of these, 16 patients (2.0%) had J-wave syndrome: 7 patients (0.9%) had type-1 patterns; 5 patients (0.6%) had type-2 patterns; 2 patients (0.3%) had type-3 patterns; and 2 patients (0.3%) had Brugada syndrome-type ECG patterns. A J-point elevation≥0.2 mV, which is considered to be more dangerous, was found in only 2 patients with Brugada syndrome-type ECG patterns, both of whom suffered perioperative lethal arrhythmias. Patients with J-wave syndrome ECG patterns, even dangerous patterns, are not necessarily associated with a higher risk of perioperative cardiac events. However, Brugada syndrome type ECG patterns should be carefully monitored.

Prevention of cardiac events caused by surgical stress in aged rats: simultaneously activating β2-adrenoceptor and inhibiting β1-adrenoceptor

Increased plasma catecholamine levels are associated with a high risk of perioperative cardiac events in aged individuals undergoing non-cardiac surgical interventions. Given the different effects of β1-adrenoreceptor (β1AR) and β2-adrenoreceptor (β2AR) stimulation by catecholamine in cardiomyocytes, this study evaluated whether simultaneous inhibition of β1AR and activation of β2AR is better than separate application in reducing the risk of perioperative cardiac events in aged rats undergoing non-cardiac surgery. Male aged Sprague–Dawley (SD) rats were divided into five groups. Normal group received no treatment. Surgery group received an abdominal surgery with hypoxia. group, group and group received surgery and hypoxia with metoprolol (100 mg/kg·d), fenoterol (250 μg/kg·d) or both, respectively. The drugs were given three days before surgery with treatment continued through post-surgical day 7. The results showed that simultaneous activation of β2AR with a β2AR agonist and inhibition of β1AR with a selective β1AR blocker normalized myocardial oxygen consumption, decreased myocardial damage, augmented cardiomyocyte survival, improved cardiac function, reduced the incidence of arrhythmia, thus decreasing the occurrence of cardiac events in perioperative aged rats undergoing non-cardiac surgery. The results demonstrated that combined use of β2AR agonist and β1AR blocker achieved better general effects than use of either one alone. Our results provide a new insight into preventing perioperative cardiac events for elderly patients undergoing surgical stress.

Influence of nitrous oxide anesthesia, B-vitamins, and MTHFR gene polymorphisms on perioperative cardiac events: the vitamins in nitrous oxide (VINO) randomized trial.

Nitrous oxide causes an acute increase in plasma homocysteine that is more pronounced in patients with the methylenetetrahydrofolate reductase (MTHFR) C677T or A1298C gene variant. In this randomized controlled trial, the authors sought to determine whether patients carrying the MTHFR C677T or A1298C variant had a higher risk for perioperative cardiac events after nitrous oxide anesthesia and whether this risk could be mitigated by B-vitamins. The authors randomized adult patients with cardiac risk factors undergoing noncardiac surgery, to receive nitrous oxide plus intravenous B-vitamins before and after surgery, or to nitrous oxide and placebo. Serial cardiac biomarkers and 12-lead electrocardiograms were obtained. The primary study endpoint was the incidence of myocardial injury, as defined by cardiac troponin I increase within the first 72 h after surgery. A total of 500 patients completed the trial. Patients who were homozygous for either MTHFR C677T, or A1298C gene variant (n=98; 19.6%) had no increased rate of postoperative cardiac troponin I increase compared with wild-type and heterozygous patients (11.2 vs. 14.0%; relative risk 0.96; 95% CI, 0.85-1.07; P=0.48). B-vitamins blunted the rise in homocysteine, but had no effect on cardiac troponin I increase compared with patients receiving placebo (13.2 vs. 13.6%; relative risk 1.02; 95% CI 0.78 to 1.32; P=0.91). Neither MTHFR C677T and A1298C gene variant, nor acute homocysteine increase are associated with perioperative cardiac troponin increase after nitrous oxide anesthesia. B-vitamins blunt nitrous oxide-induced homocysteine increase but have no effect on cardiac troponin I increase.

Plasma N-Terminal Pro-B-Type Natriuretic Peptide Is Predictive of Perioperative Cardiac Events in Patients Undergoing Vascular Surgery

Background/AimsIdentification of patients at high risk for perioperative cardiac events (POCE) is clinically important. This study aimed to determine whether preoperative measurement of plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) could predict POCE, and compared its predictive value with that of conventional cardiac risk factors and stress thallium scans in patients undergoing vascular surgery.MethodsPatients scheduled for non-cardiac vascular surgery were prospectively enrolled. Clinical risk factors were identified, and NT-proBNP levels and stress thallium scans were obtained. POCE was the composite of acute myocardial infarction, congestive heart failure including acute pulmonary edema, and primary cardiac death within 5 days after surgery. A modified Revised Cardiac Risk Index (RCRI) was proposed and compared with NT-proBNP; a positive result for ischemia and a significant perfusion defect (≥ 3 walls, moderate to severely decreased, reversible perfusion defect) on the thallium scan were added to the RCRI.ResultsA total of 365 patients (91% males) with a mean age of 67 years had a median NT-proBNP level of 105.1 pg/mL (range of quartile, 50.9 to 301.9). POCE occurred in 49 (13.4%) patients. After adjustment for confounders, an NT-proBNP level of > 302 pg/mL (odds ratio [OR], 5.7; 95% confidence interval [CI], 3.1 to 10.3; p < 0.001) and a high risk by the modified RCRI (OR, 3.9; 95% CI, 1.6 to 9.3; p = 0.002) were independent predictors for POCE. Comparison of the area under the curves for predicting POCE showed no statistical differences between NT-proBNP and RCRI.ConclusionsPreoperative measurement of NT-proBNP provides information useful for prediction of POCE as a single parameter in high-risk patients undergoing noncardiac vascular surgery.

Clinical value of myocardial perfusion scintigraphy as a screening tool in liver transplant candidates

A cardiac evaluation before orthotopic liver transplantation (OLT) is imperative. Previous investigations have demonstrated that mild to moderate reversible perfusion defects on myocardial perfusion scintigraphy (MPS) in general are associated with a low risk for perioperative cardiac events. The objective of this study was to assess any perfusion defects in consecutive patients with chronic liver disease who were undergoing OLT. OLT candidates underwent extensive cardiovascular screening that included, among other methods, MPS. Patients who had no contraindications for surgery and underwent OLT were followed up. The occurrence and risk of complications and mortality were compared in 3 groups of patients: patients with normal MPS results, patients with any reversible defect, and patients with a fixed perfusion defect on MPS. In all, 156 subsequent patients underwent OLT. One or more reversible segmental perfusion defects on MPS were present in 14 patients (<3 segments, n = 12; 3 segments without obstructive coronary artery disease, n = 2). The risk of complications did not differ significantly between patients with normal MPS findings and patients with a reversible perfusion defect (odds ratio = 3.04, 95% confidence interval = 0.65-14.26, P = 0.16), although the study was not sufficiently powered to show a difference. The presence of 1 or more reversible defects on MPS was significantly associated with an increased incidence of all-cause 1-year mortality (hazard ratio = 3.17, 95% confidence interval = 1.02-9.83, P = 0.046). No significant difference in the outcomes of patients with normal MPS findings and patients with a fixed defect on MPS was found; the study was, however, not adequately powered to do so. In conclusion, the results of this small cohort study indicate that patients with mild to moderate reversible perfusion defects on MPS may have inferior survival characteristics in comparison with patients with normal MPS results. A prospective, adequately powered study is required to confirm the results of this study.

Preoperative cardiac risk assessment in geriatric patients with hip fractures: an orthopedic surgeons’ perspective

Hip fracture is one of the most common orthopedic conditions and is associated with significant morbidity and mortality. With a progressively aging population, the annual incidence of hip fracture is expected to increase substantially. Emerging evidence suggests that early surgery (<24 h) minimizes complications secondary to immobilization, including orthostatic pneumonia and venous thromboembolism. Delayed surgical repair (>48 h) has been consistently demonstrated to be associated with an increased risk of 30-day and 1-year mortality. Nonetheless, early surgery necessitates a shorter time for preoperative medical preparation, in particular cardiac assessment. Patients who undergo emergent orthopedic surgery are therefore at greater risk of perioperative cardiac events than those who undergo elective surgery. In addition, the prompt triage system for preoperative cardiac assessment not only identifies patients at high risk of perioperative cardiac complications but also reduces unnecessary cardiac consultations for low-risk patients. We review the current recommendations for preoperative cardiac assessment adapted for patients with hip fracture and describe our current triage system for preoperative cardiac consultation.Electronic supplementary materialThe online version of this article (doi:10.1007/s00198-010-1393-0) contains supplementary material, which is available to authorized users.

Perioperative Management of the Patient With Cardiac Disease

The overall incidence of perioperative death is relatively low. However, patients with coronary artery disease are at higher than average risk of perioperative cardiac complications. Thus, preoperative testing for cardiac disease should be done in certain patients in an effort to reduce postoperative mortality and morbidity. Patients who require emergent orthopaedic surgery are at greater risk of perioperative cardiac events than are those who undergo elective procedures. Certain modalities, such as beta blockers, statins, and alpha-2 agonists, may be started or continued in the postoperative period to further enhance cardiac function. We review the current recommendations for preoperative cardiac testing in orthopaedic patients and for perioperative management of orthopaedic patients with known cardiac disease.

Noncardiac Surgery for Patients with Coronary Artery Stents

Physicians are increasingly being confronted with questions regarding the appropriate management of patients with recently implanted coronary stents who are in need of noncardiac surgery. Specifically, what is the optimal timing of elective procedures and how should antiplatelet therapy be managed in these patients, especially in those in need of emergent procedures? Continued antiplatelet therapy through the perioperative period might increase the risk of surgical bleeding while interruption of antiplatelet therapy predisposes to stent thrombosis, particularly in the setting of systemic hypercoagulation that frequently occurs after some surgeries.1 In this issue of Anesthesiology, two papers from the Mayo Clinic in Rochester, Minnesota provide further insight into these perplexing issues.2,3

Perioperative care of the patient with cardiovascular disease undergoing non-cardiac surgery

The risk of perioperative cardiac events in cardiac patients undergoing non-cardiac surgery may be weighed against the benefits of proposed surgery using clinical risk factor analysis and different methods of assessing myocardial functional reserve. Stress testing modalities accurately delineate reversible myocardial ischaemia, but their positive predictive value is disputed, and it is unclear if their implementation improves outcome when compared to risk stratification alone. Similarly, it remains to be shown that preoperative coronary revascularization is an effective strategy in reducing perioperative risk. Recent reports indicate that surgery undertaken in the first weeks after percutaneous coronary interventions may be associated with a significantly increased rate of major complications. Administration of beta-blockers and alpha-2 adrenergic agonists to high-risk patients reduces surgical morbidity and mortality, and the benefits observed with beta-blockers extend long after surgery. Very close cooperation between cardiologists, anaesthetists and surgeons is necessary to minimize the risk of serious perioperative complications in urgent or emergency surgery.

Perioperative and long-term prognostic value of dipyridamole Tc-99m sestamibi myocardial tomography in patients evaluated for elective vascular surgery

Background Patients with peripheral vascular disease are at increased risk for perioperative and long-term cardiac morbidity and mortality. Substantial data exist supporting the use of preoperative clinical risk stratification and planar thallium myocardial scintigraphy. Only limited data are available assessing the role of technetium-99m (Tc-99m) single photon emission computed tomography (SPECT) for preoperative evaluation in this population. Methods and results In our study 153 patients who underwent peripheral vascular surgery were followed up for up to 4 years after preoperative dipyridamole Tc-99m sestamibi SPECT to determine clinical and SPECT predictors of perioperative and long-term adverse cardiac events by multivariate analysis. There were no statistically significant clinical or SPECT predictors of perioperative risk, although no perioperative events occurred in patients with normal scans. Abnormality in the left anterior descending (LAD) territory (risk ratio = 3.1; 95% confidence interval, 1.4-7.1) was the only statistically significant univariate predictor of long-term death or myocardial infarction. Only abnormality in the LAD territory appeared to improve model fit beyond clinical risk (risk ratio = 2.9; 95% confidence interval, 1.2-7.3; P = .02). Conclusions Patients with normal preoperative scans have a low risk of perioperative cardiac events and may safely undergo peripheral vascular surgery without further coronary intervention. However, scan abnormality in the LAD distribution confers poor long-term prognosis, suggesting that patients with this finding before peripheral vascular surgery should receive aggressive medical therapy and possibly invasive intervention to improve long-term survival.

Cardiac events in patients undergoing noncardiac surgery: shifting the paradigm from noninvasive risk stratification to therapy.

Internists and cardiologists are often asked to estimate the risk for perioperative myocardial infarction or cardiac death in patients being considered for noncardiac surgery. Estimating this risk in an individual patient is difficult and complex. Although noninvasive imaging tests are often used for this purpose, a review of the literature reveals that the positive predictive value of noninvasive imaging tests is uniformly low and that they do not provide information beyond that obtained by assessing simple clinical risk variables. Moreover, no evidence exists that noninvasive imaging tests lead to a therapeutic strategy that reduces the risk for perioperative myocardial infarction or cardiac death. Since the publication of guidelines for preoperative risk stratification by the American College of Cardiology/American Heart Association in 1996 and the American College of Physicians in 1997, three clinical trials have shown that beta-blocker therapy reduces the risk for perioperative cardiac events. This paper focuses on the relationship between risk stratification and subsequent therapy to minimize or eliminate risk. In short, the paradigm is shifting from predicting which patient is at high risk for having a perioperative cardiac event to minimizing the likelihood of such an event with specific perioperative pharmacologic therapy.

The role of myocardial perfusion scanning, heart rate variability and D-dimers in predicting the risk of perioperative cardiac complications after peripheral vascular surgery.

To study the value of a number of proposed prognostic factors in prediction of the risk of perioperative cardiac events after vascular surgery. Two hundred and ninety-seven patients undergoing peripheral vascular surgery were prospectively studied. Patients underwent preoperative 24 h ambulatory electrocardiography, measurement of haemostatic variables, myocardial assessment of perfusion by dipyridamole-thallium scintigraphy and radionuclide ventriculography. The primary endpoint was cardiac death or nonfatal myocardial infarction within 30 days of surgery. A combined endpoint included the primary endpoint plus occurrence of cardiac failure, unstable angina or serious arrhythmias. The primary endpoint occurred in 21 (7%), and the combined endpoint in 41 (14%) of patients. On multivariate analysis, increased age, previous myocardial infarction, aortic surgery, impaired heart rate variability and a positive thallium scan were independent predictors of primary end-points. Preoperative atrial fibrillation and increased fibrin D-dimer were additional predictors of the combined endpoint. Construction of receiver-operator characteristic curves to examine the incremental value of predictive models showed that sensitivity and specificity of clinical data alone for primary endpoints was 71% and 72% respectively, while for the full model (incorporating heart rate variability and thallium data) this rose to 84% and 80% (p=0.0001). Preliminary screening using clinical data has limited value in risk assessment prior to vascular surgery but preoperative heart rate variability, D-dimers and thallium scanning provide modest incremental predictive value.

Peri-operative cardiac morbidity in kidney transplant recipients: incidence and risk factors.

Renal transplant recipients are known to be at increased risk for developing cardiac disease. In both general and peripheral vascular surgery, pre-operative risk stratification (and intervention when indicated) has decreased the incidence of peri-operative cardiac complications. In this study, we set out to identify subsets of patients at high risk for peri-operative cardiac complications after a renal transplant. We retrospectively reviewed the records of 2694 adult renal transplants performed at the University of Minnesota between January 1, 1985 and December 31, 1998. We determined the incidence of peri-operative (within 30 d post-transplant) cardiac complications, including myocardial infarction (MI). Risk factors for the development of these complications were determined by multivariate analysis. We found 163 peri-operative cardiac complications, for an overall incidence of 6.1%. Specific cardiac complications included MI (n=43, 1.6%), arrhythmia (n=74, 2.7%), angina (n=31, 1.2%), cardiac arrest (n=13, 0.5%), and congestive heart failure (n= 2, 0.1%). By multivariate analysis, significant risk factors for any cardiac complication were age> or =50 yr (relative risk (RR)=3.0, p=0.0001) and pre-transplant cardiac disease (RR=3.3, p=0.0001). Not significant were diabetes mellitus (DM), cadaver donor source, pre-transplant dialysis, a history of smoking, and hypertension. Significant risk factors for peri-operative MI were age> or =50 yr, pre-existing cardiac disease, and DM. Diabetic patients with pre-existing cardiac disease were at especially high risk for peri-operative cardiac events. Patients>50 yr and those with pre-existing cardiac disease, especially if diabetic, are at significantly increased risk for developing peri-operative cardiac complications after a renal transplant. Such patients require aggressive pre-operative investigations, which may include coronary angiography, to decrease the risk of post-transplant complications.

Is simple clinical assessment adequate for cardiac risk stratification before elective non-cardiac surgery?

With surgical outcomes being the subject of increasing medical and non-medical scrutiny, there is pressure to identify patients at high risk of perioperative cardiac events, most importantly fatal and non-fatal myocardial infarction. Thomas Lee and colleagues1 have shown that a simple clinical assessment is the only risk-stratifying measure required for most patients being considered for major non-cardiac surgery. Their revised Cardiac Risk Index, based on the type of surgery and risk factors related to the individual (panel) is derived from multiple-regression analysis of a large cohort of patients (2893 in the derivation set, 1422 in the validation set) and represents a helpful simplification and improvement of their original scoring system developed in the 1970s.

Dipyridamole technetium 99m sestamibi myocardial tomography for preoperative cardiac risk stratification before major or minor nonvascular surgery

The value of dipyridamole technetium 99m sestamibi (MIBI) tomography for preoperative cardiac risk stratification was assessed in 285 consecutive patients being considered for nonvascular surgery. A “major” ( n = 140) or “minor” ( n = 89) nonvascular procedure was later done in 229 of these patients ≤4 months after dipyridamole testing. Perioperative cardiac events (unstable angina, acute ischemic pulmonary edema, nonfatal myocardial infarction, or cardiac death) occurred in 11 (8%) patients undergoing major nonvascular surgery and 1 (1%) undergoing a minor procedure. The only clinical or scintigraphic variables associated with significantly increased perioperative cardiac risk in patients having major surgery were Goldman class ≥II, an abnormal MIBI scan, and a fixed perfusion defect. In these patients, cardiac events occurred in 1% of those who had a normal MIBI study, 14% of those with an abnormal scan ( p < 0.01), 12% with a reversible MIBI defect ( p = 0.29), and 17% with a fixed MIBI defect ( p < 0.01). In the 60 patients whose Goldman class was ≥II, only an abnormal MIBI study and a fixed perfusion defect were associated with incremental risk of a perioperative cardiac event. The incidence of perioperative cardiac events in these patients was 4% with a normal MIBI scan, 27% with an abnormal study ( p < 0.05), 24% with a reversible MIBI defect ( p = 0.45), and 37% with a fixed defect ( p < 0.01). Event rates were low in patients having minor nonvascular surgery; none of the 25 with a normal MIBI study and only 1 of the 64 with an abnormal scan had a perioperative cardiac event ( p = not significant (NS). We conclude that dipyridamole MIBI tomography can provide important prognostic information in patients having major nonvascular surgery. A normal MIBI study indicates a low risk of perioperative cardiac events, whereas an abnormal study in patients with Goldman class ≥II undergoing major surgery is associated with significantly increased risk. The prognostic value of MIBI tomography in patients at low clinical risk undergoing minor surgery is limited.

Preoperative cardiac risk assessment with adenosine stress dual-isotope myocardial single-photon emission computed tomography.

Previous studies have demonstrated that pharmacologic stress thallium-201 (201Tl) myocardial scintigraphy is a useful tool to evaluate preoperative cardiac risk. The purpose of this study was to assess the utility of adenosine stress dual-isotope [rest 201Tl/stress technetium-99m (99mTc) sestamibi] myocardial single-photon emission computed tomography (SPECT) in predicting the risk of perioperative cardiac events (unstable angina, myocardial infarction, cardiac death) in patients undergoing major noncardiac surgery. We evaluated 43 consecutive patients (20 men, 23 women, mean age 64 years, range 30-83 years) within 8 weeks prior to major noncardiac surgery requiring general anesthesia. SPECT imaging was performed with 111 MBq (3 mCi) 201Tl at rest and 925 MBq (25 mCi)99mTc sestamibi during adenosine stress. Of the 43 patients, 15 (35%) had stress-induced ischemia and 28 (65%) did not. Perioperative cardiac events occurred in 4 (27%) of the 15 patients with stress-induced ischemia (2 unstable angina, 2 nonfatal myocardial infarctions) and in none of the 28 patients without inducible ischemia (p = 0.02). Adenosine stress dual-isotope myocardial SPECT is useful in determining the preoperative cardiac risk of patients undergoing major noncardiac surgery.