The effects of contemporary use of coronary stents on in-hospital mortality. Registry Committee of the Society for Cardiac Angiography and Interventions.

OBJECTIVES: This study was designed to determine the effect of coronary stents on in-hospital mortality. BACKGROUND: Despite extensive use of stents for percutaneous coronary interventions (PCIs), their effect on serious in-hospital events, especially mortality, is not well defined. METHODS: A cohort study was performed using 16,811 consecutive native-vessel PCI procedures performed on patients in the Society for Cardiac Angiography & Interventions Registry from July 1, 1996, through December 31, 1998. Patients undergoing balloon-only angioplasty were compared with those receiving a planned or unplanned stent. Procedures with other devices were excluded. Multivariable analyses adjusted for detailed clinical characteristics and for individual laboratory. RESULTS: Stents were associated with a significant reduction in in-hospital mortality (0.3%) compared with balloon procedures (0.6%; multivariable odds ratio [OR] 0.55; 95% confidence interval [CI] 0.34, 0.89; p = 0.014). The risk of emergency coronary bypass also was reduced by stenting (0.3% vs. 0.7%; multivariable OR 0.47; 95% CI: 0.29, 0.76; p = 0.002). Adjustment for the use of glycoprotein IIb/IIIa inhibitors did not change the results, and the effects of stenting relative to balloon procedures were similar in those procedures with and without glycoprotein IIb/IIIa blockade (p = 0.94). CONCLUSIONS: This study suggests that coronary stenting, compared with balloon procedures, reduces in-hospital mortality, independent of the clinical setting.

Predictors of success and major complications for primary percutaneous transluminal coronary angioplasty in acute myocardial infarction. An analysis of the 1990 to 1994 Society for Cardiac Angiography and Interventions registries.

OBJECTIVES: The purpose of this study was to determine predictors of successful coronary angioplasty for acute myocardial infarction (MI) and associated predictors of the major complications of in-hospital mortality and emergency coronary artery bypass graft surgery. BACKGROUND: Primary angioplasty is being increasingly used to treat acute MI, but factors affecting the success and major complications have not been well studied. Forty laboratories have been contributing clinical and procedural data to the Society of Cardiac Angiography and Interventions (SCA&I) on primary angioplasty for acute MI. METHODS: Univariable and stepwise multivariable logistic regression analysis of clinical and procedural variables was used to calculate predictors of success and major complications. RESULTS: There were 4,366 primary angioplasty procedures reported from 1990 through 1994, with an overall success rate of 91.5%, an in-hospital mortality rate of 2.5% and a rate of emergency surgery of 4.3%. Higher laboratory primary angioplasty volume and lower age were predictive of success. An intraaortic balloon pump in place, cardiogenic shock and a moribund condition had negative predictive effects. Unsuccessful angioplasty, cardiogenic shock or a moribund state were predictive of in-hospital death. Unsuccessful angioplasty, the absence of a history of hypertension and the absence of congestive heart failure were predictive of emergency surgery. CONCLUSIONS: The rates of success and major complications in the SCA&I Registry are similar to other series. Predictors of success and major complications can be assessed and may be useful for risk stratifying candidates for primary angioplasty in acute MI.

Long-term prognostic significance of ST segment depression during acute myocardial infarction. The Multicenter Diltiazem Postinfarction Trial Research Group.

OBJECTIVES: The purpose of this study was to evaluate the long-term prognostic value of ST segment depression on the electrocardiogram (ECG) in patients with acute myocardial infarction. BACKGROUND: The prognostic importance of ST segment depression on the ECG has been studied in small groups of patients with infarction, but larger numbers are needed. METHODS: Coronary care unit ECGs of 1,234 patients who survived the coronary care unit with acute Q wave (n = 896) or non-Q wave (n = 338) myocardial infarction were analyzed for the presence of ST segment depression. Patients were followed up for up to 4 years. RESULTS: ST segment depression was present in 607 patients. Those with ST segment depression had a 1-year mortality rate of 10.3% compared with a rate of 5.6% for those without ST segment depression (p = 0.002). This effect was seen in both the Q wave and non-Q wave subgroups. Of the 437 patients with anterior ST segment elevation, those with ST segment depression in other regions had a 13.6% 1-year mortality rate compared with a rate of 6.9% for those with no ST segment depression (p = 0.0005). Of the 514 patients with inferior ST segment elevation, those with ST segment depression in other leads had an 11.0% 1-year mortality rate compared with a 1.8% rate for those with no ST segment depression (p = 0.0001). The Cox proportional hazards model showed that ST segment depression was an independent predictor of mortality over the follow-up period. CONCLUSIONS: ST segment depression on the admitting ECG in patients with acute myocardial infarction is a predictor of increased mortality in the year after infarction.

Risk stratification in patients with first non-Q wave infarction: limited value of the early low level exercise test after uncomplicated infarcts. The Multicenter Post-Infarction Research Group.

Risk stratification using clinical and historical variables plus early low level exercise testing was performed in 141 patients with a first non-Q wave myocardial infarction. The 111 patients who performed the exercise test had a 3.6% cardiac mortality rate in the first year compared with 13.3% in the 30 patients who could not exercise (p = 0.063), and a 1 year incidence rate of recurrent cardiac events (cardiac death or recurrent nonfatal myocardial infarction) of 10.8% compared with 23.3% (p = 0.127). Patients who developed ischemia (ST depression or angina) during the test had an increased incidence of cardiac events in the year after the infarction (odds ratio greater than 3, p less than 0.05). When patients were subgrouped by the presence or absence of pulmonary congestion, the discriminatory value of the exercise test was seen to reside primarily in the cohort with pulmonary congestion. For example, ST depression during exercise in this group identified patients with a 71% incidence of cardiac events in the year after the infarction compared with 5.3% for those without ST depression (odds ratio 45, p = 0.002). In the patients without pulmonary congestion, the exercise test had no discriminatory value. It is concluded that early low level exercise testing has a limited role after an uncomplicated non-Q wave infarction, but is useful in patients with clinical markers of higher risk.

Risk of major complications from coronary angioplasty performed immediately after diagnostic coronary angiography: results from the Registry of the Society for Cardiac Angiography and Interventions.

OBJECTIVES: This study was designed to determine the risk of performing percutaneous transluminal coronary angioplasty (PTCA) at the time of diagnostic catheterization ("combined procedures"). BACKGROUND: Health care providers are under increasing pressure to combine diagnostic and interventional coronary procedures to reduce costs. However, the risk associated with combined procedures has not been rigorously assessed. METHODS: A multicenter cohort study of 35,700 patients undergoing elective PTCA from 1992 through 1995 was performed to determine the risk of major complications (myocardial infarction, emergency coronary artery bypass graft surgery or death) from combined relative to staged procedures (i.e., performing PTCA at a session subsequent to diagnostic catheterization). RESULTS: The risks of major complications from combined and staged procedures were 2.0% and 1.6%, respectively (unadjusted odds ratio [OR] 1.28, 95% confidence interval [CI] 1.05 to 1.57). After adjusting for clinical and angiographic differences and clustering by laboratory, the risk from combined procedures was not significantly elevated (multivariable OR 1.18, 95% CI 0.89 to 1.55). However, several subgroups of patients did have an increased risk from combined procedures: patients with multivessel disease (multivariable OR 1.64, 95% CI 1.13 to 2.39); women (multivariable OR 1.64, 95% CI 1.05 to 2.55); patients > 65 years old (multivariable OR 1.40, 5% CI 1.02 to 1.93); and patients undergoing multilesion PTCA (multivariable OR 1.53, 95% CI 1.06 to 2.21). The risk of combined relative to staged procedures decreased over the 4-year period (multivariable p = 0.029). CONCLUSIONS: Combining PTCA with diagnostic catheterization appears to be safe in many patients. However, several subgroups of patients may be at increased risk. Careful patient selection will most likely remain critical to ensuring the safety of combined procedures.

Risk stratification after successful coronary revascularization: the lack of a role for routine exercise testing.

OBJECTIVE: The objective of this study was to evaluate the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for exercise testing (EXT) after successful coronary revascularization (CR) using the Bypass Angioplasty Revascularization Investigation experience. BACKGROUND: The ACC/AHA guidelines state that EXT within three years of successful CR is not useful. METHODS: The 1,678 patients randomized to CR by either angioplasty or bypass surgery were required to take symptom-limited treadmill tests one, three and five years after revascularization. RESULTS: Patients who took the test at each specified time had a much lower subsequent two-year mortality than those who did not (1.9% vs. 9.4%, 3.5% vs. 12.6% and 3.3% vs. 11.0% at one, three and five years, respectively, after CR [p < 0.0001 for each]). Exercise parameters at the one- and three-year test did not improve a multivariable model of survival after including clinical parameters. Exercising to Bruce stage 3 or generating a Duke score >-6 were independently predictive of two-year survival after the five-year test. ST depression on the one-year test was associated with more revascularizations (relative risk = 1.6; p < 0.001). CONCLUSIONS: Patients with stable multivessel coronary disease who took a protocol-mandated exercise test at one, three and five years after revascularization were at low risk for mortality in the two years subsequent to each test. Exercise parameters did not improve prediction of mortality in the two years after the one- and three-year tests. The ACC/AHA guidelines on exercise testing after CR (no value for routine testing in stable patients for three years after revascularization) are supported by these results.

Limited usefulness of exercise testing and thallium scintigraphy in evaluation of ambulatory patients several months after recovery from an acute coronary event: implications for management of stable coronary heart disease. Multicenter Myocardial Ischemia Research Group.

OBJECTIVES: This study evaluated the value of noninvasive testing to predict cardiac events in patients with stable coronary disease after hospital admission (and risk stratification) for an acute coronary event. BACKGROUND: Exercise testing with thallium perfusion imaging identifies patients with obstructive coronary artery disease and has been used to stratify patients after myocardial infarction. Its usefulness for predicting cardiac events in patients with stable coronary disease after recovery from an acute coronary event was explored. METHODS: Nine hundred thirty-six patients were enrolled 1 to 6 months after hospital admission for a coronary event. Patients underwent exercise treadmill testing with planar thallium-201 scintigraphy and were followed up for an average of 23 months (range 6 to 43). End points were 1) unstable angina requiring hospital admission, nonfatal myocardial infarction or cardiac death; 2) nonfatal infarction or cardiac death; or 3) cardiac death alone. RESULTS: Twelve patients died of cardiac causes (1.2%); 32 had a nonfatal myocardial infarction (3.4%); and 79 patients (8.4%) developed unstable angina in the first year. Exercise testing improved proportional hazards models constructed from clinical variables for all three end points (p < 0.05). The perfusion scan further improved models for the end points (nonfatal infarction or cardiac death and cardiac death alone, p < 0.05). However, the exercise test with or without thallium added little to the overall prediction of primary events (area under the receiver operating curve increased from 0.649 to 0.663), and only 2% to 13% of patients with abnormal results either had a nonfatal infarction or died. CONCLUSIONS: Thallium-201 scintigraphy and exercise testing variables identify patients at risk for subsequent cardiac events. However, the poor predictive performance of these tests in this group of patients with stable coronary disease severely limits their usefulness. These results suggest a limited role for exercise and thallium testing in predicting cardiac events in patients with known coronary disease.

Importance of exercise capacity in the interpretation of a myocardial ischemic response to exercise testing. Multicenter Study of Myocardial Ischemia Group (MSMI).

Patients who were stable 1 to 6 months after a cardiac event underwent routine exercise testing with thallium scintigraphy. The prognosis of patients with good exercise capacity (Bruce stage 3) was similar whether or not ischemia was demonstrated and similar to patients with reduced exercise capacity and no ischemia, whereas the presence of both ischemia and a reduced exercise tolerance identified patients with a significantly poorer prognosis.

The independence of cycle length variability and exercise testing on predicting mortality of patients surviving acute myocardial infarction. The Multicenter Postinfarction Research Group.

Cycle length variability (CLV), defined as the standard deviation of normal cycle length intervals, has been found to be a powerful predictor of subsequent mortality in a population of 808 survivors of acute myocardial infarction. Decreased CLV is associated with a significant increase in mortality. CLV remained an independent predictor of outcome even after adjusting for left ventricular ejection fraction, clinical risk factors, heart rate and ventricular arrhythmias. In the same population of survivors of acute myocardial infarction, the results of exercise testing also strongly predicted outcome, with those failing to take the test having the worst survival, and those completing the low-level stress test taken before discharge having the best prognosis. The hypothesis that the status of stress test (completed; did not complete; failed to take) and CLV were measuring the same factor related to mortality was tested. Although the distribution of CLV was shifted to higher CLV in patients who completed the test and to lower CLV in those who failed to take the test, both predictors of mortality remained independent predictors of long-term mortality (average of 31 months of follow-up) after controlling for each other. Moreover, subgroups with an approximate 15-fold difference in mortality were defined using both variables (CLV less than 50 ms, did not take test had a 54% mortality; CLV greater than 100 ms, completed the test had a mortality of 3.5%). CLV is a measure of autonomic tone; it is not strongly related to exercise ability and using the results of both stress testing and CLV results in the identification of subgroups of postinfarction patients with markedly disparate risks of mortality.

Usefulness of low-level exercise testing early after acute myocardial infarction in patients taking beta-blocking agents.

The value of low-level exercise testing early after acute myocardial infarction (AMI) in 207 patients taking beta-blocking drugs was evaluated in a multicenter study of prognosis after AMI. After stratifying patients according to the absence of significant rales upon admission or pulmonary congestion on the admitting chest x-ray, the results of the exercise test (ability to complete the 9-minute protocol) permitted a large cohort (108 patients, 52% of exercising patients) with no deaths from cardiac causes in the year after AMI to be identified. The results suggest that even in patients taking beta-blocking agents, low-level exercise testing together with clinical stratification has value in identifying a large group of patients with a good prognosis after AMI.

Psychological determinants of anginal pain perception during exercise testing of stable patients after recovery from acute myocardial infarction or unstable angina pectoris.

The objective of this study was to test the hypothesis that psychological factors are determinants of anginal symptoms during positive exercise tests. The sample consisted of clinically stable patients who were enrolled in the Multicenter Study of Myocardial Ischemia 1 to 6 months after admission to a coronary care unit. Among 186 post-myocardial infarction patients, 151 developed ischemia (i.e., a stress-induced myocardial perfusion defect) without symptoms (silent ischemia) and 35 developed angina with ischemia (symptomatic ischemia) during a thallium exercise test; among 39 patients who had been hospitalized for unstable angina, 24 developed silent ischemia and 15 developed symptomatic ischemia. Two sets of psychometric tests were administered: set 1, factors that influence awareness of physical symptoms, and set 2, factors associated with biases toward or against reporting perceived symptoms. Two hundred eleven patients produced complete data in each set. Analysis of set 1 factor scores revealed significant effects of symptom status (p = 0.006) and index event (p = 0.02), but no interaction. No effects were found in set 2. Patients who are clinically stable after recovery from an acute coronary event and who experience angina during exercise testing are more aware of physical symptoms in general than are comparable patients with silent ischemia. Psychological biases toward or against reporting perceived symptoms do not differentiate these groups. Thus, it appears that silent ischemia is probably "silent" in the sense of being truly asymptomatic rather than of stoic endurance or denial of perceived symptoms.

Long-term prognosis after first Q-wave (transmural) or non-Q-wave (nontransmural) myocardial infarction: analysis of 593 patients.

Follow-up results in 593 patients less than or equal to 7 years (mean 4.7) after hospital discharge for their first myocardial infarction (MI) are presented. Patients were grouped according to the presence or absence of Q waves on electrocardiograms after the MI and by peak serum glutamic oxalacetic transaminase (SGOT) level during hospitalization. Cardiac mortality varied. Patients with Q-wave infarcts and an SGOT level less than or equal to 240 IU/liter had a cardiac mortality of 3.1% per year, whereas patients with Q-wave MI and an SGOT level greater than 240 IU/liter had an 11% 6-month mortality and a 3.8% per year cardiac mortality thereafter. However, patients with non-Q-wave (nontransmural) MI had a excellent survival rate for 2 years (96.8%) which continued in patients aged less than or equal to 60 years thereafter. However, patients with non-Q-wave infarcts aged greater than 60 years had a 12% per year cardiac mortality in the third post-MI year and an additional 12% died each year thereafter. Early mortality was related to enzyme level, whereas late mortality was a function of type (Q-wave or non-Q-wave) and age.

Effect of smoking on lipid and thrombogenic factors two months after acute myocardial infarction.

Cigarette smoking is linked to increased cardiac morbidity and mortality, and has been shown to affect both lipid profiles and thrombotic factors in healthy subjects. However, the influence of smoking on the atherothrombotic environment has not been studied in a large population of patients after acute myocardial infarction (AMI). Blood samples and medical history, including smoking status, were obtained from 1,045 patients at a 2-month visit after AMI. Smokers were asked to refrain 24 hours before the visit, but not all complied. Measurements included total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, apolipoprotein-B, apolipoprotein-A, triglycerides, factor VII, factor VIIa, von Willebrand factor, D-dimer, and plasminogen activator inhibitor. There were 247 current, 443 past, and 349 nonsmokers. After adjustment for clinical variables, current smokers had higher levels of total cholesterol and apolipoprotein-B than past and nonsmokers (p <0.01). High-density lipoprotein cholesterol and apolipoprotein-A levels were similar between groups. Fibrinogen was elevated in current (p = 0.001) and past (p = 0.029) smokers, compared with nonsmokers. Smokers who smoked within 24 hours of blood sampling had higher apolipoprotein-B (p = 0.005), total cholesterol (p = 0.001), and fibrinogen (p = 0.015) levels than those who refrained from smoking. In conclusion, postinfarction patients, who historically have higher levels of atherogenic lipids than healthy subjects, have increased levels of these lipids attributed to active smoking. After smoking cessation, lipid profiles approach nonsmoker levels, but fibrinogen remains elevated. Smoking within 24 hours of blood sampling was associated with further adverse prothrombotic and lipogenic effects.

Electrocardiographic subset analysis of diltiazem administration on long-term outcome after acute myocardial infarction. The Multicenter Diltiazem Post-Infarction Trial Research Group.

The effect of diltiazem on long-term outcome after acute myocardial infarction (AMI) was assessed in 2,377 patients enrolled in the Multicenter Diltiazem Post-Infarction Trial and subsequently followed for 25 +/- 8 months. The study population included 855 patients (36%) with at least 1 prior AMI before the index infarction and 1,522 patients (64%) with a first AMI, of whom 409 (27%) had a first non-Q-wave AMI, 664 (44%) a first inferior Q-wave AMI, and 449 (30%) a first anterior Q-wave AMI. This post hoc analysis revealed that, among patients with first non-Q-wave and first inferior Q-wave AMI, there were fewer cardiac events during follow-up in the diltiazem than in the placebo group, and that the reverse was true for patients with first anterior Q-wave AMI or prior infarction. The diltiazem:placebo Cox hazard ratio (95% confidence limits) for the trial primary end point (cardiac death or nonfatal reinfarction, whichever occurred first) was: first non-Q-wave AMI-0.48 (0.26, 0.89); first inferior Q-wave AMI-0.66 (0.40, 1.09); first anterior Q-wave AMI-0.82 (0.51, 1.31); and prior AMI-1.11 (0.85, 1.44). Use of cardiac death alone as an end point gave an even more sharply focused treatment difference: first non-Q-wave AMI-0.46 (0.18, 1.21); first inferior Q-wave AMI-0.53 (0.27, 1.06); first anterior Q-wave AMI-1.28 (0.68, 2.40); prior infarction-1.26 (0.90, 1.77). Further analysis revealed that these differences in the effect of diltiazem in large part reflected the different status of the 4 electrocardiographically defined subsets in terms of left ventricular function.(ABSTRACT TRUNCATED AT 250 WORDS)

A simplified lesion classification for predicting success and complications of coronary angioplasty. Registry Committee of the Society for Cardiac Angiography and Intervention.

In 1988, the American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures presented a classification of coronary lesions utilizing 26 lesion features to predict the success and complications of balloon angioplasty. Using data from the Registry of the Society for Cardiac Angiography and Interventions (SCAI) we evaluated the ability of this classification to predict success and complications. Lesion success, death in hospital, emergency cardiac bypass surgery, and major adverse events were evaluated in 41,071 patients who underwent single-vessel angioplasty from January 1993 to June 1996. Logistic models using the ACC/AHA lesion classification, vessel patency, or both, were compared. A new classification based on the interaction of the ACC/AHA classification plus lesion patency was compared with the existing ACC/AHA classification. Vessel patency, added to the ACC/AHA classification, improved prediction of lesion success (p

Bypass Angioplasty Revascularization Investigation: patient screening, selection, and recruitment.

Percutaneous transluminal coronary angioplasty (PTCA) is currently performed in many patients seeking care because of severe manifestations of multivessel coronary artery disease. Previously, the majority of such patients would have undergone coronary artery bypass grafting (CABG). No definitive evidence is available as to which initial revascularization strategy has the best long-term clinical and economic outcomes. The Bypass Angioplasty Revascularization Investigation (BARI) is the largest of several recent clinical trials that were designed to test the hypothesis that an initial strategy of PTCA in selected patients with multivessel coronary artery disease does not compromise long-term clinical outcome compared with an initial strategy of CABG. This report describes how patients were screened, selected, and recruited in BARI and how this process may influence the results and the interpretation of the trial. During the enrollment period, 25,200 patients undergoing diagnostic coronary angiography at the participating institutions or with off-site angiograms referred to BARI investigators were screened for BARI eligibility. Excluded from screening were patients without coronary artery disease, those with single-vessel disease, prior revascularization, primary congenital, valvular, or myocardial disease, and age > 80 years. Slightly more than half of the patients screened (12,670) were not clinically eligible for BARI because of left main disease, insufficient symptoms, emergency revascularization, or other logistic reasons. Thus, 12,530 patients had severe angina and/or ischemia and were clinically eligible for BARI. Nearly 33% of them (4,110) had multivessel disease, which was suitable for both PTCA and CABG.(ABSTRACT TRUNCATED AT 250 WORDS)

Left coronary artery dissection with an amplatz-shaped catheter. The role of vigorous inspiration during contrast injection.

We present a case of iatrogenic left main coronary artery dissection during selective coronary arteriography in which the dissection was likely precipitated by respiratory-induced changes in catheter position. We further comment on changes in technique which may have averted the dissection.

Severe coarctation of the aorta with pulmonary edema. An unusual presentation of a traumatic aortic aneurysm.

A patient with an unrecognized rupture of the ascending aorta developed severe pulmonary edema three weeks following the initial injury. This is a distinctly unusual manifestation of this injury. Emergency resection of the traumatic aneurysm was required to reverse the rapidly deteriorating clinical situation. The early recognition and surgical treatment of this lesion would have avoided this complication.

Selection of coronary bypass. Anatomic, physiological, and angiographic considerations of vein and mammary artery grafts.

Results of direct coronary revascularization with 511 grafts in 213 patients from 1971 to 1974 are reviewed. To improve an early saphenous vein graft (SVG) patency of 84 per cent in the first 85 patients, we have used internal mammary artery grafts (IMAG), when possible, since January, 1973. In 1973 to 1974, 15 patients had SVG's only (36 grafts) and 113 received one or two IMAG's with or without additional SVG's (total 282 grafts); in 26 we used a crossed double IMAG. Forty-seven of 48 patients with unstable angina survived and did well. Flows in SVG's and IMAG's were comparable. Flows in right IMAG's to diagonal or marginal vessels were higher than in right IMAG's to right or left anterior descending (LAD) vessels. In 12 patients with both SVG and IMAG, there was no difference in flow response of either graft to vasoactive drugs. Survival, functional, and patency results with IMAG's were as good as or better than results with SVG's. We conclude that IMAG's yield higher patency and comparable flow rates to SVG's and should be used when the IMA approximates the recipient artery in size and when a high pulsatile free flow is measured from the end of the graft. IMAG's are also safe and feasible for unstable angina.

Epicardial pacemaker complicated by cardiac tamponade and constrictive pericarditis.

Following insertion of an epicardial pacemaker, our patient developed cardiac tamponade complicated by subacute constrictive pericarditis. Echocardiographic findings and intracardiac pressures were typical of constrictive pericarditis, which was confirmed at surgery. Although rare, these unusual complications should be considered in patients who develop evidence of reduced cardiac output following either transvenous or epicardial electrode placement.