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Objectives: This study was designed to test the usefulness of a bedside assay as compared to a laboratory method of troponin testing to predict adverse cardiac outcome of chest pain patients., Methods: We studied 358 ER visits of patients suspected of a non ST-elevation acute coronary syndrome. cTnI (Immulite, DPC) on a lab analyser and cTnT (Cardiac Reader, Roche) at bedside were measured at baseline. The between-assay level of concordance, reporting turnaround times and clinical outcomes during 180 days of follow-up were assessed. Death and myocardial infarction were then evaluated according to troponin result, either concordant negative, discordant or concordant positive., Results: Discordance occurred in 11.4% (41/358) of cases. The proportion of patients with a positive cTnI and negative cTnT result (8.9%) versus the reverse (2.5%) differed significantly (p<0.001). The median time gained using the rapid test was 72 min. The rate of death and/or MI was 25% (10/40) among patients with discordant results as compared to 7.5% (17/228) with a concordant negative result (p<0.001). All patients from the discordant group with an event had a positive cTnI result, while cTnT was negative., Conclusion: Patients with a discordant reading were at high risk of adverse cardiac outcome, which was only identified by the laboratory cTnI assay. Markedly, the use of the rapid assay saved time at the expense of clinical sensitivity.

Background: Despite the use of aspirin, reocclusion of the infarct-related artery occurs in approximately 30% of patients within the first year after successful fibrinolysis, with impaired clinical outcome. This study sought to assess the impact of a prolonged anticoagulation regimen as adjunctive to aspirin in the prevention of reocclusion and recurrent ischemic events after fibrinolysis for ST-elevation myocardial infarction., Methods and Results: At coronary angiography <48 hours after fibrinolytic therapy, 308 patients receiving aspirin and intravenous heparin had a patent infarct-related artery (Thrombolysis In Myocardial Infarction [TIMI] grade 3 flow). They were randomly assigned to standard heparinization and continuation of aspirin alone or to a 3-month combination of aspirin with moderate-intensity coumarin, including continued heparinization until a target international normalized ratio (INR) of 2.0 to 3.0. Angiographic and clinical follow-up were assessed at 3 months. Median INR was 2.6 (25 to 75th percentiles 2.1 to 3.1). Reocclusion (< or =TIMI grade 2 flow) was observed in 15% of patients receiving aspirin and coumarin compared with 28% in those receiving aspirin alone (relative risk [RR], 0.55; 95% CI 0.33 to 0.90; P<0.02). TIMI grade 0 to 1 flow rates were 9% and 20%, respectively (RR, 0.46; 95% CI, 0.24 to 0.89; P<0.02). Survival rates free from reinfarction and revascularization were 86% and 66%, respectively (P<0.01). Bleeding (TIMI major and minor) was infrequent: 5% versus 3% (P=NS)., Conclusions: As adjunctive to aspirin, a 3-month-regimen of moderate-intensity coumarin, including heparinization until the target INR is reached, markedly reduces reocclusion and recurrent events after successful fibrinolysis. This conceptual study provides a mechanistic rationale to further investigate the role of prolonged anticoagulation after fibrinolytic therapy.

Restenosis after coronary angioplasty is the single complication that most limits this revascularization procedure in clinical practice. The process is largely unpredictable and the lesion-related factors predisposing to restenosis are poorly understood, with little consensus in published reports. In this study using detailed quantitative angiographic measurements to assess 490 lesions, the simple lesion characteristics associated with restenosis were defined and the relation to the restenosis process documented. Restenosis was defined as an absolute deterioration in the minimal lumen diameter by greater than or equal to 0.72 mm, a criterion based on the 95% confidence intervals for repeat angiographic measurements. This was chosen in an attempt to separate spurious changes due to a poor angiographic result and the variability of angiographic measurements from significant changes due to the restenosis process. The principal determinants of restenosis were found to be a large improvement in the minimal lumen diameter at the time of dilation (1.13 mm for the restenosis group compared with 0.86 mm for the no restenosis group [p less than 0.0001]) and an optimal postangioplasty result (minimal lumen diameter 2.28 mm in the restenosis group compared with 2.05 mm [p less than 0.001] in the no restenosis group, corresponding to a 25% and a 30% diameter stenosis, respectively [p less than 0.0001]). These observations reported for the first time suggest that the distinction needs to be made between a "clinical restenosis" of greater than or equal to 50% diameter stenosis and the "restenosis process" as measured by the absolute changes occurring during and after angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise electrocardiographic (ECG) testing during follow-up after coronary angioplasty is widely applied to evaluate the efficacy of angioplasty, even in asymptomatic patients. One hundred forty-one asymptomatic patients without previous myocardial infarction underwent quantitative exercise ECG testing and quantitative coronary angiography 1 to 6 months after successful angioplasty in single vessel coronary artery disease to 1) determine the value of exercise ECG testing to detect "silent" restenosis, and 2) assess the long-term prognostic value of exercise ECG testing and coronary angiography. The prevalence of restenosis (defined as greater than or equal to 50% luminal narrowing at the dilation site) was 12% in this selected study group. Of 26 patients with an abnormal exercise ECG (ST segment depression greater than or equal to 0.1 mV), only 4 (15%) showed recurrence of stenosis. Sensitivity and specificity for detection of restenosis were 24% and 82%, respectively. One hundred thirty-four patients (95%) were followed up 1 to 64 months (mean 35) after exercise ECG testing and coronary angiography. Thirty-two patients (24%) experienced a cardiac event: in 25 patients (78%) the initial event was recurrent angina pectoris (New York Heart Association class III or IV) and in 7 patients (22%) it was myocardial infarction, although cardiac death did not occur. The mean interval between exercise ECG testing and the initial cardiac events was 14 months (range 1 to 55), whereas 47% of the initial events took place less than or equal to 6 months after exercise ECG testing.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to assess the immediate geometric changes in coronary stenosis that occur after implantation of intra-coronary stents, a quantitative angiographic analysis (automatic delineation of contours) was performed in 18 patients. Following angioplasty, the implantation of a stent significantly increases the diameter and area of the stenotic segment in absolute values. This improvement is attended by a significant decrease in resistance and in the theoretical trans-stenotic pressure gradient. Beside its role as mechanical support of the dilated arterial wall, the stent possesses an intrinsic force of dilatation confirmed by the results of quantitative angiographic analysis.

Coronary restenosis occurs fairly early after transluminal coronary angioplasty, as suggested by anatomico-clinical, isotopic and angiographic studies. Its incidence, as reported in the literature, varies according to the clinical selection of patients, to the number of patients with follow-up angiography and the timing of this procedure, and to the criteria used to define restenosis. In this prospective study we endeavoured to determine the exact date at which restenosis takes place, as well as its true incidence, by means of 6 different angiographic criteria. The population studied was divided into five groups and each group underwent coronary arteriography at a different date: during the 1st, 2nd, 3rd, 4th and 5th post-angioplasty months respectively. In 424 of the 500 patients thus examined (84.8 p. 100), coronary angiography involved automatic detection of contours and made quantitative analysis possible. Coronary restenosis was found to occur early, with a peak of incidence in the 3rd month. Its incidence varied considerably depending on the criterion used. A critical analysis of the data has prompted us to use a criterion based on absolute values determined by quantitative angiographic analysis.

Data from experimental, clinical, and pathologic studies have suggested that the process of restenosis begins very early after coronary angioplasty. The present study was performed to determine prospectively the incidence of restenosis with use of the four National Heart, Lung, and Blood Institute and the 50% or greater diameter stenosis criteria, as well as a criterion based on a decrease of 0.72 mm or more in minimal luminal diameter. Patients were recatheterized at 30, 60, 90, or 120 days after successful percutaneous transluminal coronary angioplasty (PTCA). After PTCA all patients received 10 mg nifedipine three to six times a day and aspirin once a day until repeat angiography. Of 400 consecutive patients in whom PTCA was successful (less than 50% diameter stenosis), 342 underwent quantitative angiographic follow-up (86%) by use of an automated edge-detection technique. A wide variation in the incidence of restenosis was found dependent on the criterion applied. The incidence of restenosis proved to be progressive to at least the third month for all except NHLBI criterion II. At 4 months a further increase in the incidence of restenosis was observed when defined as a decrease of 0.72 mm or more in minimal luminal diameter, whereas the criteria based on percentage diameter stenosis showed a variable response. The lack of overlap between the different restenosis criteria applied affirms the arbitrary nature of angiographic definitions currently in use. Restenosis should be assessed by repeat angiography, and preferably ascertained according to the change in absolute quantitative measurements of the luminal diameter.

The vasodilatory action of molsidomine was studied by intracoronary injection of its active metabolite, Sin 1. In 10 patients repeat coronary angiography in multiple projections was performed before and 2 minutes after administration of 1 mg of Sin 1, and before and after a second injection 60 minutes later. Contours of obstructed and non-obstructed segments of the left coronary artery were quantitatively analysed with a computer-based angiography analysis system. Immediately after its administration, Sin 1 increased the mean diameters of 44 normal coronary segments by 12% (P less than 0.001). Significant vasodilation (8%) was still observed after 60 minutes. At that time, repeated administration of Sin 1 increased the vasodilation by an additional 14% with respect to the control situation. An increase in obstruction diameter was observed in 6 out of 8 obstructed segments. Mean increase in the minimal obstruction diameter was still 10% after 60 minutes.

Numerous criteria for the assessment of the immediate and late results of percutaneous transluminal coronary angioplasty (PTCA) are currently in use. Here, the values and limitations of the transstenotic gradient (TG), visual qualitative angiogram assessment, quantitative coronary angiography and the coronary flow reserve (CFR) will be discussed. Although measurement of the TG may be clinically useful, current data suggest that it does not accurately reflect the "true" pressure-flow-resistance across coronary lesions. Furthermore, the widely applied method of visual interpretation of coronary angiograms is hampered by several serious shortcomings: large intra- and interobserver variabilities, and lack of correlation with pathologic as well as intraoperative findings. In contradistinction, CFR and minimal luminal cross-sectional area (MLCA) appear to be more reliable parameters for judging the physiologic importance of (residual) coronary obstructions. In fact, given the curvilinear relation between CFR and MLCA (r = 0.92), the available evidence suggests that at the moment quantitative coronary angiography--with measurement of the MLCA immediately after PTCA--is the method of choice in assessing the efficacy of coronary angioplasty.