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For primary angioplasty of acute myocardial infarction (AMI), the relation of treatment benefit and time has been debated. The present study aimed to evaluate, in a single-center cohort of patients with ST-segment elevation AMI, which time intervals were carefully and consistently measured, and the relations among ischemic time, in-hospital delays, and in-hospital survival. We included 499 patients (mean age 59 years; 80% men) who underwent successful primary percutaneous transluminal coronary angioplasty (PTCA) for AMI admitted < or =6 hours after symptom onset. The population was divided into tertiles with respect to time between onset of symptoms and admission, onset of symptoms to Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow, and time from admission to TIMI grade 3 flow. Univariate analysis followed by multiple logistic regression was performed using the variables linked to mortality in the univariate analysis to assess the relation between predictor variables and in-hospital mortality. The in-hospital mortality rate was 3.2%. There was no significant relation between the various tertiles of time intervals and in-hospital mortality. After linear logistic regression, only age (odds ratio [OR] 1.79 per 10 years), female gender (OR 3.56), and door-to-TIMI 3 time (OR 1.27 per 15 minutes) were independently correlated with in-hospital mortality. [ABSTRACT FROM AUTHOR]

Background: Few studies have examined the long-term outcome of primary PTCA for acute myocardial infarction, especially in thrombolysis-eligible patients., Methods: Retrospective analysis of a consecutive cohort of 228 patients treated with primary angioplasty for ST-segment elevation myocardial infarction, less than 6 h after symptom onset, of whom 203 were discharged alive and had long-term follow-up., Results: With an average follow-up of 497+/-40 days, actuarial survival rates were 94.4+/-0.02 and 86.8+/-0.06% at 2 and 4 years, respectively. Multivariate analysis showed that lack of beta-blocker therapy at discharge (RR 6.5 and 95% CI: 1.97-21.47) and age (RR 1.09 per year and 95% CI: 1.03-1.16), but not left ventricular ejection fraction were the two independent predictors of late mortality., Conclusions: In thrombolysis-eligible patients treated with primary PCI and discharged alive, reinfarction and mortality rates are low. It appears particularly important to enforce prescription of beta-blockers at discharge is an important goal in this population.

Study Objectives: To explore the diagnostic performance of MRI for the diagnosis of acute myocarditis, using a comprehensive imaging approach., Design and Settings: Twenty patients with myocarditis and 7 age-matched and gender-matched control subjects underwent comprehensive MRI. Magnetic resonance (MR) examinations included axial T2-weighted sequences, precontrast and postcontrast ECG-gated T1-weighted sequences in axial and short heart axis, cine-MRI, and serial dynamic turbo fast low-angle shot (turboFLASH) acquisitions in the short axis following Gd injection for a period of 2 min. Precontrast and postcontrast images were postprocessed using subtraction. Two observers read all images qualitatively and quantitatively. Myocardial enhancement was compared between patients and control subjects., Patients: Myocardial involvement was focal in 6 patients examined within 1 week from clinical onset, and diffuse in the remaining 14 patients examined later., Results: Qualitatively, contrast-enhanced T1-weighted subtracted images had 100% sensitivity and specificity for myocardial involvement. Postcontrast T1-weighted images were able to discriminate the early phase (nodular enhancement) from the later phase of myocarditis (diffuse enhancement). Quantitatively, myocardial enhancement was 56% +/- 3.2% in patients, vs 29% +/- 3.1% in control subjects using T1-weighted MRI (p < 0.0001). Serial turboFLASH images displayed greater myocardial enhancement between 25 s and 120 s in patients than in control subjects (p < 0.0001); however, there was marked enhancement of skeletal muscles in both early and late stages of myocarditis compared to control subjects (p < 0.0001)., Conclusion: On the basis of subtracted cardiac-gated T1-weighted images and serial postinjection turboFLASH images, our study shows that myocarditis is largely, at least in the early stages, a focal process in the myocardium. It also provides evidence of transient skeletal muscle involvement, which may actually be useful for diagnosis.

Diabetes mellitus is one of the main risk factors of coronary atherosclerosis. The relative risk of cardiovascular disease is 2 to 4 times higher in type II diabetes than in the general population. The number of cases, especially type II, is increasing, especially as the definition of diabetes has been changed recently by the specialist scientific societies (American Diabetic Association, World Health organisation and ALFEDIAM) to include all patients with fasting glucose levels > or = 7 mmol/L on two occasions. Therefore, in the next 25 years, the number of diabetic patients will probably double, not only because of this new definition but also because of the combined effects of an ageing population, dietary changes (with an increase in obesity) and a progressively more sedentary and urbanized life-style in the so-called "emerging" countries.

Unlabelled: 201TI reverse redistribution is a common finding early after reperfusion therapy for myocardial infarction. Its mechanism and clinical implications remain unclear. The aim of this study was to clarify the relationships between reverse redistribution, microvascular perfusion, and myocardial viability., Methods: Resting, 10-min-postinjection, and redistribution 201TI data obtained for 33 patients 8 and 42 d after the onset of acute myocardial infarction were compared with echocardiographic wall motion measured acutely and on day 42. Microvascular perfusion was assessed by myocardial contrast echocardiography performed 10 min after restoration of complete patency of the infarct artery., Results: Marked significant reverse redistribution was found on day 8 (absolute change, 7.5%+/-7.9% of the 10-min-postinjection defect size; P<5x0.000001) and significantly decreased on day 42 (2.7%+/-6.8%; P = 0.004 between days 8 and 42). The 10-min-postinjection defect size best predicted the final infarct size on day 42 and was closely related to microvascular perfusion. Patients with adequate reperfusion had a smaller postinjection defect on day 8 (21.1%+/-14.6%) and a larger reverse redistribution (10.2%+/-6.1%) than did patients with no reflow (35.3%+/-13% and 3.2%+/-9.2%, respectively; P<0.04 for both)., Conclusion: Reverse redistribution was marked early after myocardial infarction in patients with complete patency of the infarct artery and decreased in subsequent weeks. Reverse redistribution was associated with restoration of adequate microvascular reperfusion and with myocardial salvage and viability. The early postinjection scans on day 8 were the relevant images for assessing myocardial salvage and predicting wall motion recovery.

The present interest in myocardial contrast echocardiography is related to the development of new contrast agents which can be used intravenously and the perfection of new echocardiographic technologies. Amongst the potential applications of this technique, the study of myocardial perfusion in the acute phase of myocardial infarction is one of the most promising as shown by the experience acquired over several years with intracoronary contrast echocardiography. It allows assessment of the extent of the zones at risk before recanalisation, the presence of collateral vessels and, above all, the quality of myocardial reperfusion. The demonstration of the absence of effective reperfusion of the myocardial microcirculation, or the phenomenon of no-reflow, is one of the main advantages of contrast echocardiography and has been identified as an important independent prognostic factor. This technique could therefore become essential in the evaluation of methods for reducing the extent of microvascular damage. Although many questions remain unanswered about the ideal methods of performing and analysing intravenous contrast echocardiography, the preliminary results confirm the potential of the technique in non-invasive evaluation of myocardial reperfusion in the acute phase of myocardial infarction.

Diabetes mellitus is associated with increased risk of short and long-term complications after balloon angioplasty. In patients with multivessel disease, there may be a substantial increase in long-term mortality when percutaneous transluminal coronary angioplasty (PTCA) is preferred over surgery in patients who are amenable to both techniques, which should lead to caution in selecting PTCA as a routine revascularization method for these patients. However, many diabetic patients will still require revascularization with PTCA, either for single-vessel disease or because they are poor surgical candidates. Finally, the impact of recent advances, such as stents and glycoprotein IIb/IIIa inhibitors, on the short and long-term results of percutaneous interventions is still not fully defined and deserves further study.

1. The respective contributions of coronary vascular endothelium, nitric oxide (NO) and serotonergic receptors to the effects of ergonovine on large and small coronary arteries were investigated in conscious dogs. 2. In seven dogs with an endothelium intact, ergonovine (30 - 1000 microg, i.v.) induced a biphasic response on large coronary artery with an early and transient vasodilatation (up to +2.9+/-0.5% from 3310+/-160 microm, P<0.01) followed by a sustained vasoconstriction (down to -4.9+/-0.5%, P<0.001) which occurred simultaneously with a sustained increase in coronary blood flow (CBF) (up to +100+/-26% from 28+/-4 ml min(-1), P<0.001). After endothelium removal (balloon angioplasty), the ergonovine-induced vasodilatation was abolished and vasoconstriction potentiated (-6.4+/-0.9% after vs -4.9+/-0.5% before endothelium removal, P<0.01). 3. After blockade of NO synthesis by Nomega-nitro-L-arginine (30 mg kg(-1)) in four other dogs, the early vasodilatation induced by ergonovine was abolished but the delayed vasoconstriction as well as the increase in CBF remained unchanged. 4. Both ketanserin and methiothepin (0.3 mg kg(-1)) abolished the early vasodilatation and reduced the delayed vasoconstriction induced by ergonovine. Ketanserin decreased and methiothepin abolished the reduction in coronary resistance induced by ergonovine. 5. Thus, the complex interactions between vascular endothelium and serotonergic receptors to ergonovine-induced constriction of large coronary arteries might explain the induction of coronary spasms in patients with endothelial dysfunction.

Objectives: The purpose of this study was to assess early temporal changes in myocardial perfusion pattern by myocardial contrast echocardiography (MCE) and their relation to myocardial viability in patients with reperfused acute myocardial infarction (AMI)., Background: Myocardial contrast echocardiography no-reflow is associated with poor contractile recovery after AMI. However, little is known regarding early reversibility of microvascular dysfunction and its relation to myocardial viability., Methods: Intracoronary MCE was performed immediately after reflow and 9 days later in 28 patients with a first AMI and successful coronary recanalization (Thrombolysis in Myocardial Infarction trial grade 3 flow). Semiquantitative contrast score and wall motion score (WMS) were assessed in each initially asynergic segment at initial and repeat MCE study. Low dose dobutamine echocardiography (DE) was performed at day 10, and follow-up (FU) rest echocardiography was performed 6 weeks later., Results: Among 200 initially asynergic segments, 49% exhibited no or heterogeneous contrast enhancement at initial MCE versus 24% at restudy (p < 0.001). Three groups of segments were defined according to early changes in contrast pattern: group A, "sustained no-reflow" (n = 17); group B, improved contrast score (n = 68), and group C, "sustained reflow" (n = 112). Group A segments showed no improvement in WMS at FU. In contrast, group B segments showed significant improvement in WMS at FU (p < 0.0001), and exhibited more frequently contractile reserve at DE (36% vs. 6%, p = 0.02) and contractile recovery at FU (34% vs. 7%, p = 0.03) than group A segments. Group C segments exhibited contractile reserve and contractile recovery in 47% and 51% of segments respectively., Conclusions: Improvement in MCE perfusion pattern may occur after initial no-reflow in the days following reperfused AMI and is associated with preservation of contractile reserve and gradual regional functional recovery.

Complete coronary reperfusion after thrombolysis or primary angioplasty is associated with limitation of infarct size and conservation of left ventricular function. The area of viable myocardium recovers its function secondarily, the amount of recovery being related to the precocity of reperfusion. Patients with a patent artery in the acute stage do not all recover segmental contraction to the same extent. There are considerable discrepancies between coronary patency and myocardial perfusion. Myocardial perfusion, measured in the acute phase by myocardial contrast echocardiography is the best predictor of preservation of function. This suggests that microvascular lesions are a sign of the extent and irreversibility of myocardial damage. Modern treatment of infarction should not only restore coronary patency but also ensure effective myocardial reperfusion. The factors which determine recovery of ventricular function after reperfusion during the acute phase, are, in addition to early and complete coronary recanalisation and effective myocardial reperfusion: short duration of ischaemia, small size of the area at risk, collateral circulation, ability of the myocardium to withstand ischaemia, limitation of reperfusion injury. Other factors (smoking, pre-infarction angina, the occluded artery or method of reperfusion) may play a role but the role of confounding factors is always difficult to exclude.

The systemic and coronary hemodynamic effects of mibefradil, a "nondihydropyridine" calcium antagonist acting on both L- and T-type calcium channels, were investigated in chronically instrumented conscious dogs before and after local endothelium removal of the circumflex coronary artery by angioplasty. After intravenous infusion, mibefradil (0.2 mg kg-1 min-1) decreased mean arterial blood pressure (MAP; -15 +/- 1%), increased heart rate (HR; 58 +/- 9%), and coronary blood flow (CBF; 103 +/- 14%) (all p < 0.05). Before endothelium removal, mibefradil increased the diameter of the left circumflex epicardial coronary artery (LCX) by 7.8 +/- 1.2% from 3,006 +/- 219 microns, but this dilatory effect was significantly reduced by 69% (p < 0.001) and 45% (p < 0.01), 3 and 21 days after endothelium removal, respectively. Mibefradil also reduced by 46% (p < 0.01) the potent coronary constrictor effect of ergonovine (300 micrograms intravenous bolus). These results demonstrate that mibefradil is a potent dilator of large and small coronary arteries in conscious dogs and that approximately 30% of its dilatory effect on large coronary artery is endothelium-independent. In addition, mibefradil prevents ergonovine-induced epicardial coronary constriction.