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Preoperative assessment of the cardiac patient before noncardiac surgery is common in the clinical practice of the medical consultant, anesthesiologist, and surgeon. Currently, most noncardiac surgical procedures are performed for patients of advanced age, and the number of such surgeries is likely to increase with the aging of the population. These same patients have an increased prevalence of cardiovascular disease, especially ischemic heart disease, which is the primary cause of perioperative morbidity and mortality associated with noncardiac surgery. Since 1996, 3 American College of Cardiology/American Heart Association guideline documents have been published, each reflecting the available literature, with recommendations for the preoperative cardiovascular evaluation and treatment of the patient undergoing noncardiac surgery. Our review describes the 2007 American College of Cardiology/American Heart Association guidelines, the most recent revision, focusing on a newly recommended 5-step algorithmic approach to managing this clinical problem, particularly for the patient with known or suspected coronary heart disease. Continued emphasis should be given to preoperative clinical risk stratification, with noninvasive testing reserved for those patients in whom a substantial change in medical management would be anticipated based on results of testing. Pharmacologic therapy holds more promise than coronary revascularization for the reduction of major adverse perioperative cardiac events that might complicate noncardiac surgery. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine whether stress imaging for patients who are unsuitable for exercise treadmill testing (ETT) as part of a chest pain unit (CPU) triage strategy resulted in incremental benefit in clinical outcomes and relative costs compared with patients randomized to routine hospital admission. PATIENTS AND METHODS: Clinical outcomes and medical resource utilization were examined at the Mayo Clinic in Rochester, Minn, for 212 intermediate-risk patients with unstable angina randomized to a CPU and compared with 212 patients randomized to routine admission from November 21, 1995, to March 18, 1997. Patients in stable condition in the CPU underwent ETT; if patients were unsuitable for ETT, stress imaging was performed. Costs for CPU evaluation and outcomes were assessed during a 6-month follow-up. RESULTS: During the observation period, 60 patients (28%) were admitted to the hospital. Of the 152 remaining patients, 125 (82%) underwent ETT (91 had normal results), and 27 (18%) underwent stress imaging (3 had normal results). Patients with normal ETT or stress imaging results had no primary events at 6-month follow-up. Patients admitted to the hospital who underwent stress imaging had an insignificantly higher 6-month event rate compared with patients who underwent ETT (16.7% vs 8.1%; P=.38). The standardized resource-based relative-value units (RBRVUs) for patients who underwent ETT and stress imaging during follow-up were 19.4 and 56.4 RBRVUs, respectively, compared with 51.4 (ETT) and 52.1 (stress imaging) RBRVUs for similar numbers of patients randomized to routine admission. CONCLUSIONS: Exercise treadmill testing safely stratified most intermediate-risk patients with unstable angina and was less costly than routine admission. Patients not suitable for ETT are likely to have abnormal stress imaging results. They represent a higher-risk cohort that could be routinely admitted to the hospital without reducing the effectiveness of the CPU strategy. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the use of stress testing in a community population with de novo stable chest pain, a normal resting electrocardiogram (ECG), and the ability to exercise., Patients and Methods: We identified eligible patients by searching the electronic medical record of all outpatients seen at Mayo Clinic Rochester from January 1, 2010, through December 31, 2013. We determined the frequency of initial exercise stress testing, computed tomography coronary angiography, and invasive coronary angiography, as well as the use of subsequent second procedures (including percutaneous coronary intervention [PCI] and coronary artery bypass grafting) within 90 days. Patients were followed for 5 years for death, nonfatal myocardial infarction, and hospitalization for unstable angina., Results: The data search identified 1175 patients with chest pain and normal resting ECGs. Only 331 patients underwent cardiac testing. A slight majority (185; 55.9%) underwent an exercise ECG alone. The remainder underwent exercise echocardiography (112; 33.8%), exercise single-photon-emission computed tomography (32; 9.7%), or computed tomography coronary angiography (2; 0.9%). Few patients (30; 9.1%) required additional testing within 90 days. Of the 14 patients (4.2%) who underwent invasive coronary angiography, 12 (85.7%) had significant coronary artery disease, and were referred for percutaneous coronary intervention or coronary artery bypass grafting. At 5 years, the mortality rate was 1.2%, and the combined event rate was 3.8%., Conclusion: Most community patients with chest pain and a normal resting ECG do not require further cardiac evaluation. In patients who require testing, and are able to exercise, noninvasive stress testing is preferred. Invasive coronary angiography is applied selectively and associated with a high rate of significant coronary artery disease and referral to coronary revascularization. Long-term outcomes are excellent., (Copyright © 2019 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Objective: To determine how often unnecessary resting echocardiograms that are "not recommended" by clinical practice guidelines are performed in patients with stable chest pain and normal resting electrocardiograms (ECGs)., Patients and Methods: We performed a retrospective search of electronic medical records of all outpatients seen at Mayo Clinic Rochester from January 1, 2010, through December 31, 2013, to identify residents of Olmsted County, Minnesota, with stable chest pain and known or suspected coronary artery disease who underwent resting echocardiography and had normal resting ECGs and no other indication for echocardiography., Results: Of the 8280 outpatients from Olmsted County who were evaluated at Mayo Clinic Rochester with chest pain, 590 (7.1%) had resting echocardiograms. Ninety-two of these 590 patients (15.6%) had normal resting ECGs. Thirty-three of these 92 patients (35.9%) had other indications for echocardiography. The remaining 59 patients (10.0% of all echocardiograms and 0.7% of all patients) had normal resting ECGs and no other indication for echocardiography. Fifty-seven of these 59 patients (96.6%) had normal echocardiograms. Thirteen of these 59 echocardiograms (22.0%) were "preordered" before the provider (physicians, nurses, physician assistants) visit., Conclusion: The overall rate of echocardiography in Olmsted County outpatients with chest pain seen at Mayo Clinic Rochester is low. Only 1 in 10 of these echocardiograms was performed in violation of the class III recommendation in the American College of Cardiology Foundation/American Heart Association guidelines for the management of stable angina. These unnecessary echocardiograms were almost always normal. The rate of unnecessary echocardiograms could be decreased by eliminating preordering., (Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Objective: To assess stress single-photon emission computed tomography (SPECT) and stress echocardiography use after coronary artery bypass grafting (CABG) and their effect on referral for coronary angiography and revascularization., Patients and Methods: The referral, timing, and results of stress imaging after CABG; referral for coronary angiography and revascularization; and all-cause mortality were assessed in this longitudinal, population-based, retrospective study of 1138 Olmsted County, Minnesota, patients undergoing CABG between January 1, 1993, and December 31, 2003., Results: A total of 570 patients (50.1%) underwent a stress imaging study (341 SPECT and 229 echocardiography) during the study period. Of the 1138 patients, 372 (32.7%) were referred for coronary angiography, and 144 of those patients (12.7%) underwent repeated revascularization (132 percutaneous revascularization and 12 CABG). The median interval between CABG and the index stress imaging study was 3.0 years (25th-75th percentile, 1.2-5.7 years). The results of 75.7% (258 of 341) of the stress SPECT studies and 70.7% (162 of 229) of the stress echocardiograms were abnormal. Seventy-six of 570 patients (13.3%) referred for stress imaging underwent coronary angiography within 180 days after the stress test. Repeated coronary revascularization was performed in 25 patients (4.4%) who underwent a stress imaging study within the preceding 180 days. The 5- and 10-year survival rates in the entire study cohort (83.5% and 65.1%, respectively) were not significantly different than predicted for the age- and sex-matched Minnesota population., Conclusion: Half of this community-based population of patients with CABG underwent stress SPECT or echocardiography during median follow-up of 8.9 years. Despite that approximately 75% of the results of stress imaging studies were abnormal, subsequent referral for coronary angiography within 180 days was low (13.3%), and the yield for repeated revascularization was very low (4.4%)., (Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Objective: To determine whether asymptomatic patients with atherosclerosis, indicated by the presence of coronary artery calcium on electron beam computed tomography, are at enough risk for progression of disease to justify a repeated stress single-photon emission computed tomography (SPECT) examination after an initial normal to low-risk perfusion study., Patients and Methods: We retrospectively identified patients who had abnormal results on electron beam computed tomography (coronary artery calcium score > 0) and normal to low-risk results on SPECT (defined as a summed stress score of 0-3) within a 3-month period from January 1, 1995, to October 31, 2002. Of the 504 identified patients, 285 remained after exclusion criteria were applied. Of the 285 patients, 69 (mean +/- SD age, 58.2 +/- 7.6 years; 91% male) underwent at least 1 repeated myocardial perfusion SPECT imaging study within 4 years of their initial assessment as normal or at low risk without recurrence of symptoms. The value of repeated SPECT imaging was assessed by detection of a substantial change in the repeated SPECT study and by documentation of a clinical event (death, nonfatal myocardial infarction, or revascularization). Follow-up was 100% complete at a mean of 4.3 +/- 1.6 years., Results: Only 4 patients (6%) had a substantial progression in their SPECT risk category; substantial changes on the SPECT scans occurred only in patients with a coronary artery calcium score greater than 100. Three patients underwent revascularization, yielding a 5-year rate for survival free of revascularization of 94% (95% confidence interval, 88%-100%). No deaths or nonfatal myocardial infarctions were reported., Conclusion: The principal findings of this study indicate that asymptomatic patients with initial normal or low-risk results from stress SPECT performed because of abnormal coronary artery calcium scores who remain asymptomatic are at low risk of death, myocardial infarction, or coronary revascularization. Three patients underwent revascularization by percutaneous coronary intervention despite the absence of symptoms. A substantial change in SPECT results (defined as progression from normal or low-risk summed stress score to intermediate- or high-risk summed stress score) affected 6% of patients and was not associated with any adverse hard events (nonfatal myocardial infarction or death).

Objective: To determine whether stress imaging for patients who are unsuitable for exercise treadmill testing (ETT) as part of a chest pain unit (CPU) triage strategy resulted in incremental benefit in clinical outcomes and relative costs compared with patients randomized to routine hospital admission., Patients and Methods: Clinical outcomes and medical resource utilization were examined at the Mayo Clinic in Rochester, Minn, for 212 intermediate-risk patients with unstable angina randomized to a CPU and compared with 212 patients randomized to routine admission from November 21, 1995, to March 18, 1997. Patients in stable condition in the CPU underwent ETT; if patients were unsuitable for ETT, stress imaging was performed. Costs for CPU evaluation and outcomes were assessed during a 6-month follow-up., Results: During the observation period, 60 patients (28%) were admitted to the hospital. Of the 152 remaining patients, 125 (82%) underwent ETT (91 had normal results), and 27 (18%) underwent stress imaging (3 had normal results). Patients with normal ETT or stress imaging results had no primary events at 6-month follow-up. Patients admitted to the hospital who underwent stress imaging had an insignificantly higher 6-month event rate compared with patients who underwent ETT (16.7% vs 8.1%; P=.38). The standardized resource-based relative-value units (RBRVUs) for patients who underwent ETT and stress imaging during follow-up were 19.4 and 56.4 RBRVUs, respectively, compared with 51.4 (ETT) and 52.1 (stress imaging) RBRVUs for similar numbers of patients randomized to routine admission., Conclusions: Exercise treadmill testing safely stratified most intermediate-risk patients with unstable angina and was less costly than routine admission. Patients not suitable for ETT are likely to have abnormal stress imaging results. They represent a higher-risk cohort that could be routinely admitted to the hospital without reducing the effectiveness of the CPU strategy.

Objective: To determine whether a simple clinical score, which was shown previously to predict the likelihood of severe coronary artery disease (CAD) in patients referred for coronary angiography, could predict prognosis in a separate cohort of patients with normal or mildly abnormal findings on their resting electrocardiogram (ECG) who were undergoing noninvasive evaluation for possible CAD., Patients and Methods: The study group included 2255 symptomatic patients with normal (n=1466) or mildly abnormal (nonspecific ST-T-wave abnormalities; n=789) findings on their resting ECG who were referred for exercise thallium testing between 1989 and 1991. Follow-up was 94% complete at a mean +/- SD duration of 6.9+/-1.5 years. The clinical score, which ranged from 0 (lowest risk) to 10 (highest risk), was calculated by awarding 1 point each for male sex, history of myocardial infarction, typical angina, diabetes mellitus, insulin use, and each decade of age older than 40 years., Results: In each ECG group, the clinical score was a significant predictor of cardiac death, nonfatal myocardial infarction, or late revascularization, considered individually or combined, unadjusted or with adjustment for age. Most patients had a score lower than 5; these patients had an excellent 5-year cardiac survival rate (99.7% for the normal ECG findings group and 98.8% for the ST-T-wave abnormalities group). The small subset of patients with a score higher than 5 had a much lower 5-year survival rate (923% for the 8% of patients with normal ECG findings and 86.6% for the 14% of patients with ST-T-wave abnormalities). For patients with a score of 5, the 5-year survival rate was 97.7% for the normal ECG findings group and 95.9% for the ST-T-wave abnormalities group., Conclusion: In symptomatic patients with known or suspected CAD and normal or mildly abnormal resting ECG findings, this simple, easily computed clinical score is a useful and valid tool to help determine prognosis.

Objective: To determine whether adenosine could be safely administered to patients with chronic obstructive pulmonary disease (COPD) for coronary vasodilatation during perfusion scintigraphy without causing bronchospasm., Material and Methods: The study was divided into two phases. In the monitoring phase, patients with COPD were pretreated with an inhaled bronchodilator (albuterol) and had pulmonary function monitored during the infusion of a graduated dose of adenosine. Eligibility for entry into this phase of the study was determined on the basis of results of pulmonary function testing (PFT) during resting. Once we had shown that adenosine could be safely administered to patients with COPD, an implementation phase was begun. Entry did not require resting PFT, and patients were administered adenosine without monitoring of pulmonary function. Differences between patients with normal pulmonary function or mild COPD and those with more severe COPD were analyzed statistically., Results: Of 94 patients entered into the monitoring phase, none had obvious bronchospasm. The dosage of adenosine was reduced in four patients because of a decrease in forced expiratory volume in 1 second (FEV1) of 20% in comparison with baseline (FEV1 before administration of albuterol). The mean FEV1 decreased slightly from 1.83 L after administration of albuterol to 1.78 L during the maximal adenosine dose. Patients with a remote history of asthma, positive result of a methacholine challenge test, or mild COPD (FEV1 60 to 80% of the maximal predicted value for age) did not differ significantly in their response to infusion of adenosine from those with moderate or severe COPD (FEV1 30 to 59% of the maximum predicted for age). Of 117 patients in the implementation phase, 2 had bronchospasm during infusion of adenosine that was quickly terminated by stopping the administration in one patient and reducing the dose of adenosine in the other., Conclusion: This study shows that adenosine can be safely administered intravenously to selected patients with known or suspected COPD to produce coronary vasodilatation for myocardial perfusion imaging. Patients who are within the guidelines established for this study should be considered for adenosine coronary vasodilatation with use of bronchodilator pretreatment, a graduated dose of adenosine, and regular chest auscultation during the infusion.

Objective: To determine whether subsets of patients referred for a clinically indicated radionuclide adenosine stress study respond differently to a standard infusion of adenosine., Material and Methods: We assessed multiple clinical and hemodynamic variables in the first 2,000 patients who underwent adenosine perfusion studies in our laboratory. A relevant clinical variable was defined as one that was significantly associated with changes in heart rate and blood pressure during adenosine infusion. Relevant clinical variables that were most significantly related to hemodynamic variables included age, gender, rhythm (atrial fibrillation), diabetes, and left ventricular function. These variables were then related to symptomatic responses (adverse effects) to adenosine infusion. To determine whether the different peripheral responses to adenosine reflected clinically important differences in coronary vasodilatation, we compared perfusion imaging with coronary angiographic findings in the 408 patients who underwent both studies within 6 months of each other., Results: The decrease in systolic blood pressure was greater and the reflex tachycardia was less in patients 70 years of age or older and in those with insulin-dependent diabetes in comparison with younger patients and those without type 1 diabetes. Men had smaller decreases in blood pressure and smaller increases in heart rate than did women. Patients with atrial fibrillation and those with left ventricular ejection fraction less than 40% had smaller decreases in blood pressure and smaller increases in heart rate than did those in sinus rhythm or those with an ejection fraction of 40% or more. Age 70 years or older, male gender, atrial fibrillation, and left ventricular ejection fraction less than 40% were associated with fewer symptoms and less severe chest pain in comparison with patients without these variables. For patients with coronary angiograms, the relationship between coronary artery disease evident on angiography and perfusion abnormalities noted on scintigraphy was not different for any of the relevant clinical variables., Conclusion: Common clinical patient subsets are associated with different peripheral hemodynamic and symptomatic responses to infusion of adenosine. Despite these observations, however, the ability to detect coronary artery disease with perfusion imaging is not obviously altered.

Objective: To determine whether worsening exercise performance on serial exercise radionuclide angiography identifies patients at increased risk of future cardiac events., Material and Methods: One hundred nine medically treated patients with previous Q-wave myocardial infarction underwent two exercise radionuclide angiographic studies at least 6 months apart (median, 16 months) without an intervening clinical event. Worsening exercise performance between the two studies was defined by five criteria: (1) lower (5% or more) peak exercise ejection fraction; (2) worsening peak exercise wall motion score; (3) combination of criteria 1 and 2; (4) worsening serial delta (exercise - rest) ejection fraction; or (5) increasing exercise ST-segment depression of 1 mm or more. Patients were followed up for a median duration of 3.9 years after the second exercise study., Results: Five cardiac deaths and 10 nonfatal myocardial infarctions occurred during follow-up. A Cox proportional hazards analysis failed to show an association between any of the aforementioned variables and cardiac events. Of the 15 patients with cardiac events, 4 (27%) had a lower (5% or more) exercise ejection fraction and 2 (13%) had a worsening exercise wall motion score. Of the 94 patients without cardiac events, 37 (39%) had a lower (5% or more) exercise ejection fraction and 28 (30%) had a worsening serial exercise wall motion score (not a statistically significant difference)., Conclusion: Worsening exercise performance on serial exercise radionuclide angiography does not identify patients at increased risk of future cardiac events.

Objective: To compare the hemodynamic responses and the adverse effects associated with two coronary vasodilators used for pharmacologic stress testing., Design: We retrospectively studied the results of adenosine and dipyridamole perfusion imaging in a large group of patients who underwent pharmacologic stress radionuclide perfusion imaging., Material and Methods: One thousand patients given dipyridamole between April 1989 and April 1991 (before adenosine became available) were compared with 1,000 patients given adenosine between April 1991 and October 1992. A standard protocol was used to infuse the drugs before myocardial perfusion imaging with 201Tl or 99mTc sestamibi., Results: Peak heart rate was higher (85 versus 83 beats/min; P = 0.02) and systolic blood pressure was lower (129 versus 133 mm Hg; P < 0.0001) with adenosine than with dipyridamole. More patients had a decrease in systolic blood pressure of 30 mm Hg or more with adenosine than with dipyridamole (P = 0.002). Horizontal or downsloping ST-segment depression of 1 mm or more occurred in 9% of patients who received adenosine and in 8% of those who received dipyridamole. Adverse effects occurred in 78% of the adenosine study group and in 50% of the dipyridamole group (P < 0.0001). Chest pain was the most common symptom with both drugs. Atrioventricular block occurred in 76 patients who received adenosine but in none who received dipyridamole. Because of adverse effects, 28% of patients who received dipyridamole required extra monitoring time (mean, 6 +/- 5 minutes beyond the standard protocol). Aminophylline was administered to 163 and 6 patients, respectively, in the dipyridamole and adenosine study groups., Conclusion: Adenosine causes slightly greater systemic vasodilation than does dipyridamole. Adverse effects occur less often with dipyridamole but, in comparison with adenosine, are more difficult to manage and necessitate more monitoring time as well as fairly frequent intravenous use of aminophylline for reversal.

Objective: To determine whether patients with impaired left ventricular function and one- or two-vessel coronary artery disease who manifest severe ischemia during exercise radionuclide angiography have a lower rate of subsequent cardiac events when initial management is revascularization rather than medical therapy., Design: During a median follow-up of 100 months, we compared the outcome between 37 patients who underwent a revascularization procedure and 22 who received medical therapy at the Mayo Clinic between September 1980 and December 1985., Material and Methods: The revascularization therapy consisted of coronary artery bypass grafting in 31 patients and coronary angioplasty in 6. Overall survival and survival free of initial cardiac events were compared statistically for the medically and surgically treated patients., Results: Eleven deaths occurred in the patients who received medical therapy and 9 in the revascularization group. Five-year overall survival was 58% in the medically treated patients versus 84% in the revascularization group. A significant association was noted between type of treatment and overall survival (adjusted chi 2 = 6.20; P = 0.013). Twenty patients had initial cardiac events--7 in the medically treated group (3 cardiac deaths and 4 nonfatal myocardial infarctions) and 13 in the revascularization group (3 cardiac deaths, 3 out-of-hospital cardiac arrests, and 7 nonfatal myocardial infarctions). Survival free of cardiac events at 5 years was 72% in the medically treated patients and 66% in those who underwent revascularization. No association was detected between type of treatment and survival free of cardiac events., Conclusion: These nonrandomized data suggest that overall survival for patients with one- or two-vessel coronary artery disease, impaired left ventricular function, and severe exercise-induced ischemia may be improved by revascularization, but the subsequent cardiac event rates are not.

Objective: To address the current clinical applications, outcomes, and limitations of coronary angioplasty in the setting of acute myocardial infarction., Design: We review the results of several large trials in which various strategies of thrombolysis and primary, immediate adjunctive, rescue, or deferred adjunctive coronary angioplasty were used in patients with acute myocardial infarction., Material and Methods: Four strategies for the utilization of angioplasty in myocardial infarction have been developed and are based on the timing and concurrent use of thrombolytic therapy., Results: Primary coronary angioplasty without prior thrombolytic therapy is as effective as thrombolytic therapy for salvaging myocardium. Results of a meta-analysis of recent trials suggest potential benefits of increased survival and decreased reinfarction in comparison with the results of thrombolysis in recent trials. Immediate adjunctive angioplasty after thrombolytic therapy has been tested in three large, randomized trials. The results suggest that this strategy is associated with increased risks without benefits of increased survival or improved left ventricular function. Rescue angioplasty may be helpful after failed thrombolytic therapy. Ongoing randomized trials might further clarify the benefits of rescue angioplasty. Because of the inherent difficulty in the noninvasive identification of patients with persistent reocclusion, diagnostic coronary angiography early after thrombolytic therapy may be necessary. Deferred adjunctive angioplasty during the weeks after infarction to prevent recurrent ischemia was not shown to decrease mortality or reinfarction in two large trials., Conclusion: Primary coronary angioplasty is the treatment of choice for patients with contraindications to thrombolytic therapy. Certain high-risk subgroups may also benefit from primary angioplasty.

Objective: Immediate angioplasty and thrombolysis followed by conservative therapy are treatment strategies for acute myocardial infarction. The objective of this study was to compare the costs of these two strategies during a 12-month period., Methods: Of 103 patients with acute myocardial infarction who sought medical assistance within 12 hours after onset of symptoms, 4 were excluded from analysis for various reasons, 51 received tissue plasminogen activator, and 48 underwent immediate angioplasty as the initial revascularization strategy. The main outcome determinants were direct monetary costs and indirect measures of costs, including duration of hospital stay and return to work., Results: No significant difference in monetary costs between the two initial treatment strategies could be demonstrated. A trend was noted toward a briefer hospital stay and fewer late in-hospital procedures for patients treated initially with immediate angioplasty. Other measures of indirect costs were not statistically different., Conclusion: The hypothesis that thrombolysis followed by conservative therapy would be more cost-effective than immediate angioplasty in the treatment of patients with acute myocardial infarction could not be substantiated. The two strategies seem to have similar cost-effectiveness.

Percutaneous transluminal coronary angioplasty (PTCA) has assumed an increasing role in the preoperative preparation of patients with an abdominal aortic aneurysm (AAA). The influence of this modality on perioperative morbidity and long-term outcome has not been substantiated. To determine the effect of PTCA, we analyzed a cohort of 2,452 patients who underwent repair of an AAA between 1980 and 1990 at our institution. We compared the cardiac morbidity, mortality, and survival of patients who had preoperative coronary revascularization by PTCA or coronary artery bypass grafting (CABG). The overall perioperative mortality for the 2,452 patients was 2.9%. Preoperative coronary revascularization was necessary in 100 patients (4.1%)--86 had CABG and 14 had PTCA. Of these 100 patients, 95% had cardiac symptoms. Patients selected for PTCA, in comparison with CABG, had significantly less three-vessel disease but not significant differences in cardiac history or ejection fraction. During the study period, the use of PTCA increased significantly. The perioperative rate of myocardial infarction for patients with prior CABG was 5.8% in comparison with 0% for those with prior PTCA. No hospital deaths occurred in either group. The median interval between coronary revascularization and repair of an AAA was 10 days for PTCA and 68 days for CABG. The 3-year survival was not statistically different between CABG (82.8%) and PTCA (92.3%) groups. The rate of late cardiac events (at 3 years) was 56.5% in the PTCA group and 27.3% in the CABG group. We conclude that PTCA as part of a highly selective approach to coronary revascularization before repair of an AAA minimizes cardiac-related events and death.(ABSTRACT TRUNCATED AT 250 WORDS)

Recognizing patients with coronary artery disease in whom severe left ventricular dysfunction is attributed to a chronic decrease in myocardial blood flow without infarction is often difficult but important because such patients may benefit from surgical revascularization. Herein we describe a patient with severe left ventricular dysfunction who had appreciable resting wall motion abnormalities; tomographic thallium-201 myocardial scintigraphy performed while the patient was resting identified viable myocardium. Subsequent revascularization improved regional and global left ventricular function considerably.

The purpose of this study was to determine the prognosis of medically treated patients with three-vessel coronary artery disease and normal left ventricular function who do not have severe ischemia on exercise radionuclide angiography. The absence of severe ischemia was defined prospectively (in accordance with previously published criteria) as the presence of at least one of the following: (1) workload more than 600 kg-m/min, (2) ST-segment depression of less than 1 mm, or (3) unchanged or increased left ventricular ejection fraction during exercise. Of 42 patients (33% in functional class III or IV) followed up for a median duration of 53 months (range, 1 to 84 months), 22 had initial cardiac events during follow-up, including 6 cardiac deaths, 5 nonfatal myocardial infarctions, and 11 late (a median of 29 months after the exercise study) coronary revascularization procedures. At 4 years of follow-up, the overall survival was 83%. Survival free of cardiac death or myocardial infarction was 77%, and survival free of all cardiac events was 59%. Even in the absence of severe exercise-induced ischemia, medically treated patients with three-vessel coronary artery disease and normal left ventricular function still have a poor long-term outcome.

The risk of perioperative myocardial infarction and death was evaluated in 50 patients (mean age, 68 years) with severe coronary artery disease who underwent a noncardiac operation after revascularization had been achieved by successful percutaneous transluminal coronary angioplasty. Before angioplasty, all patients were thought to be at high risk for perioperative complications on the basis of assessment of clinical variables and findings on specialized diagnostic tests. Of the 50 patients, 31 had Canadian Heart Association class III or IV angina or unstable angina. All patients who underwent functional testing had positive results. At catheterization, 38 patients (76%) had multivessel disease. The 50 patients underwent 54 noncardiac operations at a median of 9 days after angioplasty. The overall frequency of perioperative myocardial infarction was 5.6%, and the mortality was 1.9%. Two nonfatal non-Q-wave infarctions and one fatal Q-wave infarction occurred. In patients who have undergone successful angioplasty for severe coronary artery disease, the risk of major cardiac complications associated with a noncardiac surgical procedure is low.

The 12-lead electrocardiogram in 23 patients with an evolving first myocardial infarction (12 anterior and 11 inferior) was correlated with the myocardial area at risk measured by tomographic perfusion imaging with technetium-99m sestamibi. Of several electrocardiographic factors, only the extent and quantity (with and without R-wave normalization) of ST depression differed significantly between inferior and anterior evolving infarction. The myocardial area at risk was greater in anterior than in inferior evolving infarction. The extent of the myocardium at risk correlated modestly (r = 0.58) with total ST displacement in anterior evolving infarction and with total ST depression normalized to the R wave (r = 0.70) in inferior evolving infarction. Because of the large standard errors (9 to 15% of the left ventricle), estimates of the myocardial area at risk based on these electrocardiographic variables have minimal clinical value in the individual patient.

A patient with symptoms of acute myocardial infarction but ST-segment depression rather than elevation constitutes a clinical dilemma for which few guidelines exist. Herein we describe such a patient, in whom serial tomographic imaging with a new radiopharmaceutical agent, technetium-99m sestamibi, was useful in demonstrating a large area of myocardium at risk and subsequent substantial benefit from acute reperfusion therapy. Because this perfusion agent washes out slowly from the myocardium, imaging can be delayed for several hours; thus, acute reperfusion therapy can be performed without delay. Subsequent imaging, however, will reflect myocardial perfusion at the time of administration of the radionuclide. Additional studies with this agent may be valuable in identifying those patients with ST-segment depression who will benefit from acute reperfusion therapy.

Diastolic filling can be measured by radionuclide ventriculography with use of several techniques including those based on gated and list-mode acquisitions, the first-pass method, and the nuclear probe. Radionuclide ventriculography specifically assesses volumes, rates of volume change, and intervals during ventricular filling. Normal values for diastolic filling measurement vary depending on the individual radionuclide methods used and the age of the patient. Comparative studies of the radionuclide method with contrast angiographic and Doppler echocardiographic techniques for measuring diastole are discussed, and the advantages and disadvantages of the radionuclide techniques are explored. The role of radionuclide assessment of diastolic function in specific clinical examples of hypertrophic cardiomyopathy, hypertension, anthracycline-induced cardiomyopathy, and coronary artery disease is reviewed. Radionuclide ventriculography is an accurate and easily applicable procedure for studying left ventricular volume changes in diastole.

A careful clinical history and physical examination are the most important components of the preoperative assessment of the cardiac patient who is to undergo a noncardiac surgical procedure. From these factors and the nature of the surgical procedure planned, a reasonable estimate of potential cardiac risk can be formulated to guide judicious preoperative testing for further definition of potentially high-risk patients. The potential risks associated with an invasive cardiac procedure or surgical intervention must always be considered along with the potential benefits of such a procedure in an attempt to reduce the cardiac risk of noncardiac operations. Aggressive and conscientious preoperative assessment and perioperative care of the high-risk patient by the concerted efforts of the medical consultant, anesthesiologist, and surgeon may substantially diminish cardiac-related morbidity and mortality during noncardiac surgical procedures.

We investigated whether exercise radionuclide angiography provides prognostic information in addition to that identified by resting left ventricular function and coronary anatomy in patients with medically treated coronary artery disease. Clinical follow-up (median, 21.7 months) was obtained in 424 medically treated patients who underwent exercise radionuclide angiography and coronary angiography. The mean age of the study population was 58 years, and 67% were men. Cardiac death occurred in 16 patients, nonfatal myocardial infarction in 16, and nonfatal out-of-hospital cardiac arrest in 1. Univariate analysis showed that multiple variables were associated with future cardiac events, including number of diseased vessels, exercise and rest radionuclide ejection fraction, history of myocardial infarction, exercise and rest left ventricular end-systolic and end-diastolic volume indices, peak exercise workload, age, abnormal resting electrocardiogram, and peak exercise ST-segment depression. Only three variables were independently associated with cardiac events on follow-up: number of diseased vessels, radionuclide ejection fraction at rest, and age. In patients with three-vessel disease and a resting radionuclide ejection fraction of more than 40%, a subgroup with higher risk could not be identified on the basis of exercise radionuclide response.