Comparison of protective effects of preinfarction angina pectoris in acute myocardial infarction treated by thrombolysis versus by primary coronary angioplasty with stenting.

The protective effects of preinfarction angina were evaluated in acute myocardial infarction (AMI) treated by primary percutaneous transluminal coronary angioplasty (PTCA) and stenting. We studied 613 patients with AMI. Group 1 (n = 306) was treated by conventional medical therapies and coronary thrombolysis and group 2 (n = 307) was treated by primary PTCA supported by stenting. Each group was subdivided into those with and without preinfarction angina within 24 hours before the onset of AMI. There was no significant difference in clinical characteristics between the subgroups of groups 1 and 2. In group 1, there were differences between patients with preinfarction angina (n = 84) and those without (n = 222) in in-hospital mortality (11% vs 18%), pump failure (Killip classes 3 and 4) (11% vs 21%, p <0.05), left ventricular ejection fraction at discharge (52 +/- 13% vs 48 +/- 14%, p <0.05), and peak creatine kinase (2,106 +/- 1,637 vs 2,764 +/- 2,154 U/L, p <0.02). In group 2, however, there was no significant difference between those with preinfarction angina (n = 82) and those without (n = 225) in mortality (6% vs 6%), pump failure (12% vs 12%), left ventricular ejection fraction (50 +/- 13% vs 50 +/- 13%) and peak creatine kinase (3,285 +/- 2,306 vs 3,291 +/- 2,262 U/L). Multivariate analysis indicated that preinfarction angina was an independent determinant of in-hospital death and pump failure in group 1, but not in group 2. We conclude that the protective effects of preinfarction angina in AMI are not evident in those treated by primary PTCA and stenting, possibly because of the overwhelming protective effects of complete coronary revascularization provided by primary PTCA and stenting.     

Evaluation of left ventricular function using Tei index in patients with preinfarction angina.

OBJECTIVE: The study investigated whether preinfarction angina influences left ventricular functions assessed using Tei index, which is an independent predictor for left ventricular dysfunction in acute myocardial infarction. METHODS: We studied 96 patients with acute myocardial infarction with ST segment elevation (80 men, 16 women; mean age 57.5+/-9.9 years) who were assigned into 2 groups: with and without preinfarction angina. All patients were serially evaluated by 2-dimensional and Doppler echocardiography on the days 1, 6, and 30, and were followed up for 30 days for incidence of complications. RESULTS: We observed that Tei index was lower on the days 1, 6 and 30 (0.49+/-0.20 vs. 0.59+/-0.20, p=0.003, 0.46+/-0.20 vs. 0.56+/-0.20, p=0.001, 0.44+/-0.20 vs. 0.53+/-0.10, p=0.01) in patients with preinfarction angina as compared with those without angina. Tei index significantly decreased during follow-up (0.49+/-0.20, 0.46+/-0.20, 0.44+/-0.20; p=0.02) in patients with preinfarction angina, while it did not change significantly in patients without preinfarction angina (p=0.2). Echocardiographically significant improvements were observed in E deceleration time, isovolumic relaxation time and ejection time in all patients, whereas significant improvements in ejection fraction, wall motion score index and isovolumic contraction time were observed only in patients with preinfarction angina during follow-up. Mortality, Killip class >or=2, pericarditis, atrial fibrillation, and left ventricular thrombus were lower in patients with preinfarction angina. CONCLUSION: These data indicated that the patients with preinfarction angina had better preserved systolic left ventricular function and Tei index values. Also, it was observed that preinfarction angina may cause earlier and more prominent myocardial functional recovery and confer protection against complications on short-term after first acute myocardial infarction.     

Beneficial effect of preinfarction angina on in-hospital outcome is preserved in elderly patients undergoing coronary intervention for anterior acute myocardial infarction.

BACKGROUND: Preinfarction angina improves survival after acute myocardial infarction (AMI) in nonelderly but not elderly patients in the thrombolytic era. However, it remains unclear whether preinfarction angina has a beneficial effect on clinical outcome in elderly patients undergoing percutaneous coronary intervention (PCI). METHODS AND RESULTS: The study group comprised 484 anterior AMI patients who were admitted within 24 h of onset and underwent emergency PCI. Patients were divided into 2 groups: those aged < 70 years (nonelderly patients, n = 290) and those aged > or = 70 years (elderly patients, n = 194). Angina within 24 h before AMI was present in 42% of nonelderly patients and in 37% of elderly patients. In nonelderly patients, preinfarction angina was associated with a lower in-hospital mortality rate (1% vs 7%, p = 0.02). Similarly, in elderly patients, preinfarction angina was associated with a lower in-hospital mortality rate (6% vs 16%, p = 0.03). Multivariate analysis showed that the absence of preinfarction angina was an independent predictor of in-hospital mortality in both nonelderly (odds ratio 4.20; 95% confidence interval (CI) 1.20-10.6; p = 0.04) and elderly patients (odds ratio 3.04; 95%CI 1.06-18.1; p = 0.04). CONCLUSIONS: Angina within the 24 h before AMI is associated with better in-hospital outcomes in elderly and nonelderly patients.     

Effect of preinfarction angina pectoris on ST-segment resolution after primary coronary angioplasty for acute myocardial infarction

The presence of preinfarction angina has been shown to exert a favorable effect on left ventricular function after acute myocardial infarction (AMI). Whether or not preinfarction angina is beneficial for myocardial tissue reperfusion, however, remains to be determined. We sought to evaluate the influence of preinfarction angina on resolution of ST-segment elevation, which could be affected by microcirculatory damage after recanalization therapy. We studied 96 patients with a first AMI in whom Thrombolysis In Myocardial Infarction (TIMI)-3 flow in the infarct-related artery was established by primary angioplasty. Percent reduction in the sum of ST elevation from baseline to 1 hour after angioplasty (percent delta summation operator ST) was examined. Poor ST resolution, defined as percent delta summation operator ST <50%, was observed in 25 patients, who had a worse clinical outcome, larger infarct size, and poorer left ventricular function. On multivariate analysis, the absence of preinfarction angina, as well as anterior wall infarction, were major independent predictors of poor ST resolution, whereas age, sex, coronary risk factors, ischemic time, Killip class on admission, multivessel disease, initial TIMI flow grade, and extent of collaterals were not significant. Patients with preinfarction angina had a greater degree of ST-segment resolution than those without angina (71 +/- 21% vs 49 +/- 43%, p = 0.02). Additional ST elevation after reperfusion was noted exclusively in patients without preinfarction angina (p = 0.02). Preinfarction angina is associated with a greater degree of ST-segment resolution in patients with TIMI-3 flow after primary angioplasty, suggesting a protective effect of preinfarction angina against microcirculatory damage after reperfusion.     

The effect of pre-infarction unstable angina on the size of myocardial necrosis

INTRODUCTION AND OBJECTIVES: Recent studies suggest that preinfarction angina (PA) might induce less myocardial necrosis. The objective of this study is to evaluate whether patients with PA have smaller myocardial infarctions. METHODS: Patients with acute myocardial infarction of less than 12 hours since the onset symptoms were included. PA was defined as unstable angina at rest during the 7 days before the infarction. Infarct size was assessed with the area under the curve of CK-MB levels in the 24 hours following the onset of the infarct. RESULTS: One hundred-seventy nine patients were included, 75 (41.9%) with PA. There were more men in the group with PA (89.3% vs 70.2%, p = 0.004) and a higher prevalence of ex-smokers (38.7% vs 19.2%, p = 0.006). We did not find significant differences in myocardial infarction size between both groups, but a statistically significant interaction between PA and pre-treatment with sulfonylurea drugs was noted (p = 0.050). CONCLUSIONS: Preinfarction angina does not seem to induce less myocardial necrosis in this study. There is a significant interaction between preinfarction angina and pre-treatment with sulfonylurea drugs.     

Effect of preinfarction angina pectoris on outcome in patients with acute myocardial infarction treated with primary angioplasty (results from the Myocardial Infarction Registry

Preinfarction angina is associated with better clinical outcome in patients with acute myocardial infarction (AMI) who receive intravenous thrombolysis. This has not been proved in patients with AMI treated with primary angioplasty. We analyzed the data of the prospective multicenter Myocardial Infarction Registry (MIR). Of 14,440 patients with AMI, 774 with a prehospital delay of < or =12 hours were treated with primary angioplasty. Five hundred thirty-two patients (68.7%) had preinfarction angina. Patients with preinfarction angina were slightly older than patients without (63 vs 62 years, p = 0.042), prehospital delay was 1 hour longer (180 vs 120 minutes, p = 0.001), and arterial hypertension was more prevalent (47.6% vs 32.2%, odds ratio [OR] 1.91, 95% confidence intervals [CI] 1.39 to 2.62). There was no significant difference in hospital mortality (5.6% vs 3.3%, OR 1.75, 95% CI 0.79 to 3.87), reinfarction, stroke, or the combined end point of death, reinfarction, or stroke between the 2 groups. Logistic regression analysis showed no association of preinfarction angina with the occurrence of either death (OR 2.21, 95% CI 0.91 to 6.08) or the combined end points (OR 1.10, 95% CI 0.55 to 2.31). There was also no significant difference in mortality (6% vs 5.1%, OR 1.19, 95% CI 0.56 to 2.52), reinfarction, stroke, postinfarction angina, or the combined end points between patients with preinfarction angina within 48 hours compared with patients with preinfarction angina between 49 hours and 4 weeks before the AMI. Thus, the MIR data showed no protective effects of preinfarction angina in patients with AMI treated with primary angioplasty.     

Preinfarction angina prevents left ventricular remodeling in patients treated with thrombolysis for myocardial infarction

BACKGROUND: It has been shown that preinfarction angina may have beneficial effects on infarct size and mortality. However, there are no studies that have serially assessed the impact of preinfarction angina on left ventricular (LV) function in a large series of patients. HYPOTHESIS: The study was undertaken to determine whether preinfarction angina (within 7 days before infarction) influences LV remodeling. METHODS: In all, 119 consecutive patients with acute myocardial infarction were serially evaluated by 2-dimensional echocardiography (on Days 1, 2, 3, and 7; at 3 and 6 weeks; and at 3, 6, and 12 months following infarction). Left ventricular volumes were determined using Simpson's biplane formula and normalized for body surface area. Wall motion score index and sphericity index were calculated for each study. Coronary angiography was performed before discharge. RESULTS: Preinfarction angina was detected in 39 of 119 patients. Initial echocardiographic and clinical data as well as the incidence of patent infarct-related artery and collaterals were similar for patients with and without preinfarction angina. In the subset of thrombolysed patients, patients with preinfarction angina showed decrease of LV end-diastolic and end-systolic volumes during the follow-up period (p = 0.033 and p = 0.001, respectively), and improvement of wall motion score index (p < 0.001) and ejection fraction occurred (p = 0.001), without changing of LV shape (p > 0.05); in addition, patients with preinfarction angina had smaller LV volumes and higher ejection fraction than did those without angina, from 3 weeks onward. These favorable effects were not detected in patients not treated with thrombolysis. CONCLUSIONS: These data indicate that preinfarction angina has an inhibiting effect on long-term LV remodeling in patients who underwent thrombolysis for first acute myocardial infarction. It appears that preinfarction angina has no impact on infarct size and early postinfarction LV function.     

Does angina the week before protect against first myocardial infarction in elderly patients?

Mortality rates for coronary artery disease are greater in elderly patients. Although prodromal angina occurring shortly before an acute myocardial infarction (MI) has protective effects against ischemia, this effect has not been well documented in older patients. This study investigated whether angina 1 week before a first MI provides protection in this group of patients. A total of 290 consecutive elderly (>64 years old, n = 143) and adult patients (<65 years old, n = 147) with a first MI were examined to assess the effect of preceding angina on the short- and long-term prognosis. Elderly patients with a history of prodromal angina were less likely than those without angina to experience in-hospital death, heart failure, or the combined end point of in-hospital death and heart failure (6% vs 20.4%, p = 0.02; 10% vs 23.7%, p = 0.07; 14% vs 32.3%, p = 0.01, respectively). Left ventricular function was more frequently depressed (ejection fraction <40%) in elderly patients without (44.8%) than with (26%, p = 0.04) preinfarction angina, and the incidence of arrhythmias (complete heart block and ventricular fibrillation) was greater in the former group (16.1% vs 4%, p = 0.03). Multivariate analysis confirmed that the presence of preinfarction angina was an independent predictor of in-hospital death and heart failure in older patients (odds ratio 0.28, p = 0.009). The occurrence of angina 1 week before a first MI may confer protection against in-hospital adverse outcomes, and may preserve left ventricular function in older patients.     

Preinfarction angina as a major predictor of left ventricular function and long-term prognosis after a first Q wave myocardial infarction

Objectives. The purpose of this study was to assess the prognostic significance of preinfarction angina after a first Q wave myocardial infarction. Patients with anterior or inferior myocardial infarction were compared.Background. The effect of preinfarction angina on prognosis after anterior and inferior myocardial infarction remains unclear.Methods. A total of 291 patients with a first Q wave anterior (n = 171) or inferior (n = 120) myocardial infarction were examined to assess the effect of preinfarction angina on short- and long-term prognosis. The relation between predischarge left ventriculographic findings and preinfarction angina was also examined.Results. The presence of preinfarction angina was associated with lower peak creatine kinase activity, a lower in-hospital incidence of sustained ventricular tachycardia and fibrillation and a lower incidence of pump failure and cardiac mortality in patients with either anterior or inferior infarction. Among patients with anterior infarction, preinfarction angina was associated with a lower incidence of cardiac rupture and less need for readmission for heart failure within 1 year after the onset of infarction. In this subgroup it was also associated with a higher ejection fraction, a smaller end-diastolic volume and a lower incidence of aneurysm formation noted on ventriculography during convalescence. In patients with inferior infarction, these variables did not differ significantly in the presence or absence of preinfarction angina. Multivariate analysis confirmed that the presence of preinfarction angina was an independent predictor of development of ventricular aneurysm, late phase heart failure and 1-year cardiac mortality.Conclusions. The presence of preinfarction angina has a favorable effect on infarct expansion and late phase left ventricular function, especially in patients with anterior myocardial infarction. The mechanisms responsible for this phenomenon are not known but may be secondary to limitations of infarct size through unidentified mechanisms other than collateralization (e.g., ischemic preconditioning).     

Unstable angina: Relationship of clinical presentation,coronary artery pathology,and clinical outcome

Patients with unstable angina are heterogeneous with respect to presentation, coronary artery morphology, and clinical outcome. Subclassification of these patients based on clinical history has been proposed as a means of identifying individuals at increased cardiac risk. We applied such a classification system to 129 patients discharged from a coronary care unit with a diagnosis of acute myocardial ischemia. Patients were then assessed for cardiac events (recurrent angina requiring revascularization, myocardial infarction, death) 12 months following hospital discharge. Patients were classified as recent onset unstable angina preinfarction (n = 42), crescendo unstable angina preinfarction (n = 48), and unstable angina postinfarction (n = 39). Within each of these groups, the patients were further subclassified based on the occurrence of angina on effort, at rest, or both. No attempt was made to subset patients taking antiischemic drugs at the time of clinical presentation to the physician. Coronary angiographic pathology (morphology and number of vessels involved) was similar in the subgroups, but coronary artery thrombus was statistically more likely to be found in patients with crescendo rest angina preinfarction or with frequent anginal episodes at rest postinfarction. Mortality was significantly higher for patients with unstable angina postinfarction (7.7%) than preinfarction (1.1%). No statistical differences were noted between the subgroups with respect to the occurrence of myocardial infarction or recurrent unstable angina requiring revascularization. These data suggest that subclassification of unstable angina patients based on clinical characteristics at presentation is not useful to predict subsequent myocardial infarction or recurrent angina requiring revascularization. However, as one might expect, patients with recurrent angina postinfarction have a higher mortality rate than patients with unstable angina preinfarction, and patients with recurrent rest angina, either pre- or postinfarction, are more likely to have intracoronary thrombus than patients with new onset angina or crescendo effort angina; however, the presence of thrombus did not predict a poor clinical outcome.     

High level of physical activity preserves the cardioprotective effect of preinfarction angina in elderly patients.

OBJECTIVES: The study investigated the effects of physical activity on preinfarction angina, a clinical equivalent of ischemic preconditioning (PC), in adult and elderly patients with acute myocardial infarction (AMI). BACKGROUND: Preinfarction angina seems to confer protection against in-hospital mortality in adult but not in elderly patients. However, it has been experimentally demonstrated that exercise training restores the protective effect of PC in the aging heart. METHODS: We retrospectively verified whether physical activity preserved the protective effect of preinfarction angina against in-hospital mortality in 557 elderly patients with AMI. Physical activity was quantified according to the Physical Activity Scale for the Elderly (PASE). RESULTS: In-hospital mortality was 22.2% in elderly patients with preinfarction angina and 27.2% in those without (p = 0.20). When the PASE score was stratified in quartiles (0 to 40, 41 to 56, 57 to 90, >90), a high score was strongly associated with reduced in-hospital mortality (30.8%, 32.2%, 17.2% and 15.3%, respectively, p < 0.001 for trend). Interestingly, a high level of physical activity reduced in-hospital mortality in elderly patients with preinfarction angina (35.7%, 35.4%, 12.3% and 4.23%, respectively, p < 0.001 for trend) but not in those without (23.0%, 27.2%, 26.0% and 35.0%, respectively, p = 0.35 for trend). Accordingly, the protective role of preinfarction angina on in-hospital mortality was present only in elderly patients showing a high level of physical activity (adjusted odds ratio, 0.09; 95% confidence interval, 0.01 to 0.57; p < 0.05). CONCLUSIONS: Physical activity and not preinfarction angina protects against in-hospital mortality in elderly patients with myocardial infarction. Nevertheless, the protective effect of preinfarction angina is preserved in elderly patients with a high level of physical activity.     

Outcome of percutaneous coronary intervention in unstable angina pectoris versus stable angina pectoris in two different time periods

Percutaneous coronary intervention (PCI) for unstable angina pectoris (UAP) has traditionally been associated with a higher risk of ischemic complications than that for stable angina pectoris (SAP). However, PCI procedures have evolved, so this study was designed to determine whether PCI for UAP is still associated with less favorable outcomes. In-hospital and 1-year outcomes in Dynamic Registry patients who presented for PCI with UAP (n = 2,994) or SAP (n = 1,457) between 1997 and 2002 were compared. One-year results were also compared with consecutive patients who underwent angioplasty (n = 2,431) from the 1985 to 1986 Percutaneous Transluminal Coronary Angioplasty Registry. Although Dynamic Registry patients with UAP were older and more likely to smoke (p < 0.05), have diabetes mellitus (p = 0.03), or a previous myocardial infarction (p < 0.001), procedural success was higher than in patients with SAP. By 1 year, there was greater risk of death (4.4% vs 2.6%, p < 0.01), death/myocardial infarction (9.9% vs 6.6%, p < 0.001), and death, myocardial infarction, and coronary artery bypass grafting (15.1% vs 11.6%, p < 0.01) in patients with UAP. In patients with UAP, there was no significant difference in adjusted 1-year death and death/myocardial infarction rates when comparing the waves of the Dynamic Registry with those of the Percutaneous Transluminal Coronary Angioplasty Registry, although death/myocardial infarction rates among Dynamic Registry patients were lower. However, in patients with SAP, the adjusted rate for death/myocardial infarction was lower in wave 3, and for death, myocardial infarction, and revascularization, there was a significant decrease in event rates with each successive recruitment period (p < 0.05 for all comparisons). In conclusion, in contradistinction to patients with SAP, death and death/myocardial infarction rates in patients who have undergone PCI for UAP have not significantly decreased over the past 16 years and patients with UAP remain at a greater risk of ischemic events at 1 year compared with patients with SAP.     

急性心肌梗死中缺血预适应可否保护心肌

目的探讨心肌梗死前心绞痛对心肌产生的缺血预适应,对行经皮冠状动脉介入术急性心肌梗死患者是否有近期及远期的保护作用。方法急性心肌梗死113例,介入术组(68例)行急诊经皮冠状动脉介入术,非介入术组(45例)没行再灌注治疗。观察急性心肌梗死前48h有否心绞痛发作,再分为心绞痛阳性和心绞痛阴性两亚组。观察两组患者的预后。结果介入术组的心绞痛阳性和心绞痛阴性两亚组住院期间心力衰竭、心源性休克、心肌酶峰值、心源性死亡、左室射血分数以及随诊期心力衰竭、心绞痛发生率、心源性死亡的差异无统计学意义(P>0.05);非介入术组的AP阳性亚组住院期间心力衰竭、心源性休克、心肌酶峰值及达峰时间均较低、左室射血分数较高,差异有统计学意义(P<0.05),随诊期心绞痛发生率、心源性死亡似有增高趋势,但差异无统计学意义(P>0.05)。结论心肌梗死前心绞痛对行经皮冠状动脉介入术的急性心肌梗死患者保护作用不显著,对没行再灌注治疗的急性心肌梗死患者,可改善近期预后,但远期保护作用不明显。     

Relationship between myocardial damage and C-reactive protein levels immediately after onset of acute myocardial infarction

The present study investigated the relationship between myocardial damage and C-reactive protein (CRP) levels, with no increase in creatine kinase (CK) activity, immediately after the onset of acute myocardial infarction (AMI) in 85 patients with their first reperfused anterior AMI without CK elevation on admission and no ischemic events during hospitalization. Patients were classified into those with low levels (<0.3 mg/dl) of CRP (Group L; n=67) and those with high levels (> or =0.3 mg/dl) of CRP (Group H; n=18). Group H had a higher proportion of patients with a history of preinfarction angina (89 vs 55%, p<0.01), especially unstable angina. SigmaST in leads V1-6 on admission ECG was lower in Group H than in Group L (14+/-7 vs 21+/-13 mm, p<0.05). Predischarge left ventriculography showed that the left ventricular global ejection fraction (55+/-11 vs 48+/-10%, p<0.01) and SD/chord at the left anterior descending artery lesion (-1.7+/-0.9 vs -2.3+/-0.9, p<0.01) were better in Group H. Multivariate analysis demonstrated that both CRP on admission (p=0.011) and preinfarction angina (p=0.002) were independently associated with better regional wall motion (SD/chord >-2.0) before discharge. These results suggest that the clinical situation of elevated CRP immediately after onset is associated with less myocardial damage and better left ventricular function in reperfused anterior AMI.     

Significance of preinfarction angina for preservation of left ventricular function in acute myocardial infarction.

The effect of preinfarction angina on the preservation of left ventricular function was evaluated with the use of cineventriculography in 37 patients who had either total or subtotal occlusion of the proximal left anterior descending coronary artery during the convalescent period of myocardial infarction. In 15 patients who had preinfarction angina more than 1 week before the onset of acute myocardial infarction (group A), the global left ventricular ejection fraction was 54 +/- 3% (SEM) and regional wall motion in the infarct area was 10 +/- 3%. In 10 patients who had preinfarction angina occurred within 1 week before the onset of acute myocardial infarction (group B), the left ventricular ejection fraction and regional wall motion in the infarct area were 42 +/- 3% and 1 +/- 2%, respectively. In 12 patients without preinfarction angina (group C), the left ventricular ejection fraction and regional wall motion in the infarct area were 38 +/- 3% and -1 +/- 2%, respectively. In groups B and C, both the left ventricular ejection fraction and regional wall motion in the infarct area were lower than those in group A (p less than 0.05). The collateral circulation at the onset of acute myocardial infarction was better in group A compared with groups B and C (p less than 0.05). Thus the collateral circulation, promoted by repetitive anginal episodes indicative of myocardial ischemia, causes the preservation of myocardial function.     

Costs and clinical outcomes in individuals without known coronary artery disease undergoing coronary computed tomographic angiography from an analysis of Medicare category III transaction codes

Multidetector coronary computed tomographic angiography (CCTA) demonstrates high accuracy for the detection and exclusion of coronary artery disease (CAD) and predicts adverse prognosis. To date, opportunity costs relating the clinical and economic outcomes of CCTA compared with other methods of diagnosing CAD, such as myocardial perfusion single-photon emission computed tomography (SPECT), remain unknown. An observational, multicenter, patient-level analysis of patients without known CAD who underwent CCTA or SPECT was performed. Patients who underwent CCTA (n = 1,938) were matched to those who underwent SPECT (n = 7,752) on 8 demographic and clinical characteristics and 2 summary measures of cardiac medications and co-morbidities and were evaluated for 9-month expenditures and clinical outcomes. Adjusted total health care and CAD expenditures were 27% (p <0.001) and 33% (p <0.001) lower, respectively, for patients who underwent CCTA compared with those who underwent SPECT, by an average of $467 (95% confidence interval $99 to $984) for CAD expenditures per patient. Despite lower total health care expenditures for CCTA, no differences were observed for rates of adverse cardiovascular events, including CAD hospitalizations (4.2% vs 4.1%, p = NS), CAD outpatient visits (17.4% vs 13.3%, p = NS), myocardial infarction (0.4% vs 0.6%, p = NS), and new-onset angina (3.0% vs 3.5%, p = NS). Patients without known CAD who underwent CCTA, compared with matched patients who underwent SPECT, incurred lower overall health care and CAD expenditures while experiencing similarly low rates of CAD hospitalization, outpatient visits, myocardial infarction, and angina. In conclusion, these data suggest that CCTA may be a cost-efficient alternative to SPECT for the initial coronary evaluation of patients without known CAD.     

延迟相缺血预处理心肌保护时间窗的临床探讨

目的探讨心肌梗死患者延迟相缺血预处理的心肌保护时间窗。方法行直接冠状动脉介入治疗的急性心肌梗死患者150例,根据梗死前心绞痛发作时间分为三组：无心绞痛组（1组）55例,〈72 h心绞痛组（2组）55例,〉72 h心绞痛组（3组）40例。统计患者一般临床情况、院内预后指标、出院前的左室射血分数,肌酸激酶和肌酸激酶同工酶的曲线下面积反映患者的心肌梗死面积。结果除年龄外,其余各项临床指标在三组间均无统计学差异。2组和3组的心肌梗死面积明显低于1组（P〈0.01）,但2组的充血性心力衰竭/休克、复合终点发生率明显低于1组和3组（P〈0.01或0.05）。梗死前心绞痛的心肌保护作用与年龄、抗心绞痛药物以及侧支循环无关。结论临床缺血预处理的保护时间窗不同于动物实验,可能大于72 h。     

Effect of preinfarction angina pectoris on microcirculation in patients with reperfused acute myocardial infarction

Preinfarction angina pectoris has been suggested in some studies to have a beneficial effect on left ventricular function after acute myocardial infarction (AMI). The precise mechanisms of this protection have not been fully elucidated. The effect of preinfarction angina on myocardial tissue perfusion also needs to be clarified. In this study, we investigated the influence of preinfarction angina on microvasculatory damage by using ST-segment resolution and pressure-derived collateral flow index (CFIp) as a marker of microcirculatory perfusion. METHODS: We studied 41 patients with a first AMI in whom thrombolysis in myocardial infarction (TIMI) grade 3 flow in the infarct-related artery was established by thrombolytic therapy. The percent resolution of ST-segment deviation (deltasigma ST) after thrombolysis was determined. All of the patients had TIMI grade 3 flow in IRA at the coronary angiography, which was done a mean of 4 days after AMI. Intracoronary pressure measurements and stent implantation to the IRA were performed. After angiography, CFIp was calculated as the ratio of simultaneously measured coronary wedge pressure-central venous pressure (Pv) to mean aortic pressure-Pv. RESULTS: Patients with preinfarction angina pectoris had greater percent deltasigma ST than those without PA (67 +/- 18% vs. 44 +/- 24%, p = 0.03).The mean of the coronary wedge pressure (16.4 +/- 7.4 compared with 23.2 +/- 9.4, P < 0.03) and the pressure-derived collateral flow index (0.15 +/- 0.10 compared with 0.22 +/- 0.08, P < 0.03) were significantly lower in patients with preinfarction angina compared to those without. CONCLUSION: Preinfarction angina is associated with a greater degree of ST-segment resolution and lower CFI-p in patients with TIMI-3 reflow after thrombolysis. These findings suggest that a protective effect of preinfarction angina against reperfusion injury may result in greater ST resolution and lower CFIp after AMI.     

Absence of preinfarction angina is associated with a risk of no-reflow phenomenon after primary coronary angioplasty for a first anterior wall acute myocardial infarction

BACKGROUND: No-reflow phenomenon after primary coronary angioplasty is associated with poorer left ventricular (LV) function and prognosis after acute myocardial infarction (AMI). The purpose of this study was to determine the clinical significance of preinfarction angina in the no-reflow phenomenon. METHODS AND RESULTS: A total of 40 patients with first anterior AMI were examined. All patients underwent primary balloon angioplasty or stenting within 12 h of the onset of AMI. No-reflow, defined as TIMI grade 2 flow or less without residual stenosis after angioplasty, was observed in 15 patients. Patients with no-reflow were older (67+/-9 vs. 58+/-10 years, P=0.006) and had a lower incidence of preinfarction angina (7% vs. 48%, P=0.01) than those without no-reflow. Patients with no-reflow had poorer LV function at predischarge and a higher incidence of pump failure, LV aneurysm, malignant ventricular arrhythmias or cardiac death during the hospital course in association with higher peak serum C-reactive protein levels (12.7+/-8.0 vs. 7.1+/-5.5 mg/dl, P=0.02). Multivariate analysis showed that the absence of preinfarction angina was a major independent determinant of no-reflow (RR=17.1, P=0.02). CONCLUSIONS: The absence of preinfarction angina is more frequently observed in patients with no-reflow. The beneficial effect of preinfarction angina on LV function may be explained, at least in part, by prevention of no-reflow after reperfusion.     

Does abciximab improve the prognosis of diabetics after percutaneous coronary intervention?

INTRODUCTION AND OBJECTIVES: It is known that the outcome of percutaneous coronary intervention is worse in diabetics than in non-diabetics. The aim of our study was to determine whether abciximab therapy could improve clinical outcome in an unselected diabetic population that underwent percutaneous coronary interventions. MATERIAL AND METHODS: We analyzed retrospectively 198 diabetic patients who underwent PTCA from January 1997 to January 2000. Seventy-three patients (36.7%) were treated with abciximab and the remaining 125 patients (63.3%) did not receive abciximab. The mean follow-up was 12.6 months. The events considered were death, non-fatal myocardial infarction, any revascularization procedure (including the target vessel), and hospital admission for unstable angina. RESULTS: Patients who received abciximab had more frequent previous myocardial infarction (67.1 vs. 52.8%; p = 0.04), worse left ventricular function (0.53 vs. 0.59%; p = 0.02), more frequent angiographic thrombus (67.1 vs. 36.8%; p < 0.001), more complex lesions (B2/C) (76.4 vs. 55.8%; p = 0.004), and less frequent location in left anterior descending artery (34.2 vs. 60.8%; p = 0.002). The indication for PTCA in patients who received abciximab was most often related to myocardial infarction. There were no differences between the groups in sex, age and distribution of diabetes treatment. Events were more frequent in diabetics not treated with abciximab than in those who were treated with abciximab (38 vs. 22%; p < 0.037). The patients not treated with abciximab suffered more frequently target vessel revascularization (22.7 vs. 7.2%; p < 0.007). There were no significant differences in the frequency of death or non-fatal myocardial infarction, but hospital readmissions for unstable angina were significantly more frequent in diabetics not treated with abciximab (29.1 vs. 15.9%; p = 0.045). Multivariate analysis identified abciximab as a predictor of the absence of complications during follow-up (OR: 0.45; p = 0.03). CONCLUSION: Abciximab treatment seems to reduce events in unselected diabetic patients undergoing percutaneous coronary intervention, particularly target vessel revascularization.