The relationship between symptom onset-to-needle time and ischemic outcomes in patients with acute myocardial infarction treated with primary PCI: Observations from Prague-18 Study.

OBJECTIVES: Based on previous studies with clopidogrel, the time between acute myocardial infarction (AMI) symptoms onset and primary percutaneous coronary intervention (PCI) was proven as important prognostic factor. Our aim was to assess the relationship between symptoms onset to needle time (SNT) and procedural results and the occurrence of ischemic endpoints in primary angioplasty patients treated with potent P2Y12 inhibitors. METHODS: A total of 1,131 out of 1,230 patients randomized to the Prague-18 study (prasugrel vs. ticagrelor in primary PCI) were divided into a high and a low-risk group. The effect of defined SNT on patients' ischemic endpoints and prognosis by their risk status at admission was tested. RESULTS: The median SNT was 3.2 hours. Longer SNTs resulted in a more frequent incidence of TIMI flow <3 post PCI (p=0.015). There were significant differences in the occurrence of the combined ischemic endpoint among the compared SNT groups at 30 days (p=0.032), and 1 year (p=0.011), with the highest incidence in the ≤1 h SNT group of patients. "Latecomers" (SNT>4 hs) in the high-risk group experienced more reinfarction within 1 year [OR (95% CI) 3.23 (1.09-9.62) p=0.035]; no difference was found in the low-risk group. CONCLUSIONS: In the era of intense antithrombotic medication, stratification of MI patients undergoing primary angioplasty, based on initial ischemic risk assessment affected prognosis more than symptom onset to needle time. Longer time delay was significantly related to increased incidence of ischemic events and all-cause mortality only in patients with high ischemic risk.

Stent Selection for Primary Angioplasty and Outcomes in the Era of Potent Antiplatelets. Data from the Multicenter Randomized Prague-18 Trial.

Drug-eluting stents (DES) are the recommended stents for primary percutaneous coronary intervention (PCI). This study aimed to determine why interventional cardiologists used non-DES and how it influenced patient prognoses. The efficacy and safety outcomes of the different stents were also compared in patients treated with either prasugrel or ticagrelor. Of the PRAGUE-18 study patients, 749 (67.4%) were treated with DES, 296 (26.6%) with bare-metal stents (BMS), and 66 (5.9%) with bioabsorbable vascular scaffold/stents (BVS) between 2013 and 2016. Cardiogenic shock at presentation, left main coronary artery disease, especially as the culprit lesion, and right coronary artery stenosis were the reasons for selecting a BMS. The incidence of the primary composite net-clinical endpoint (EP) (death, nonfatal myocardial infarction, stroke, serious bleeding, or revascularization) at seven days was 2.5% vs. 6.3% and 3.0% in the DES, vs. with BMS and BVS, respectively (HR 2.7; 95% CI 1.419-5.15, p = 0.002 for BMS vs. DES and 1.25 (0.29-5.39) p = 0.76 for BVS vs. DES). Patients with BMS were at higher risk of death at 30 days (HR 2.20; 95% CI 1.01-4.76; for BMS vs. DES, p = 0.045) and at one year (HR 2.1; 95% CI 1.19-3.69; p = 0.01); they also had a higher composite of cardiac death, reinfarction, and stroke (HR 1.66; 95% CI 1.0-2.74; p = 0.047) at one year. BMS were associated with a significantly higher rate of primary EP whether treated with prasugrel or ticagrelor. In conclusion, patients with the highest initial risk profile were preferably treated with BMS over BVS. BMS were associated with a significantly higher rate of cardiovascular events whether treated with prasugrel or ticagrelor.

MiR-126-3p and MiR-223-3p as Biomarkers for Prediction of Thrombotic Risk in Patients with Acute Myocardial Infarction and Primary Angioplasty.

Aim. This study was designed to evaluate the relationship between microRNAs (miRNAs), miR-126-3p and miR-223-3p, as new biomarkers of platelet activation, and predicting recurrent thrombotic events after acute myocardial infarction (AMI). Methods and Results. The analysis included 598 patients randomized in the PRAGUE-18 study (ticagrelor vs. prasugrel in AMI). The measurements of miRNAs were performed by using a novel miRNA immunoassay method. The association of miRNAs with the occurrence of the ischemic endpoint (EP) (cardiovascular death, nonfatal MI, or stroke) and bleeding were analyzed. The miR-223-3p level was significantly related to an increased risk of occurrence of the ischemic EP within 30 days (odds ratio (OR) = 15.74, 95% confidence interval (CI): 2.07-119.93, p = 0.008) and one year (OR = 3.18, 95% CI: 1.40-7.19, p = 0.006), respectively. The miR-126-3p to miR-223-3p ratio was related to a decreased risk of occurrence of EP within 30 days (OR = 0.14, 95% CI: 0.03-0.61, p = 0.009) and one year (OR = 0.37, 95% CI: 0.17-0.82, p = 0.014), respectively. MiRNAs were identified as independent predictors of EP even after adjustment for confounding clinical predictors. Adding miR-223-3p and miR-126-3p to miR-223-3p ratios as predictors into the model calculating the ischemic risk significantly increased the predictive accuracy for combined ischemic EP within one year more than using only clinical ischemic risk parameters. No associations between miRNAs and bleeding complications were identified. Conclusion. The miR-223-3p and the miR-126-3p are promising independent predictors of thrombotic events and can be used for ischemic risk stratification after AMI.

The Effect of Diabetes on Prognosis Following Myocardial Infarction Treated with Primary Angioplasty and Potent Antiplatelet Therapy.

PURPOSE: To investigate the prognostic significance of diabetes mellitus (DM) in patients with high risk acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (pPCI) in the era of potent antithrombotics. METHODS: Data from 1230 ST-segment elevation myocardial infarction (STEMI) patients enrolled in the PRAGUE-18 (prasugrel vs. ticagrelor in pPCI) study were analyzed. Ischemic and bleeding event rates were calculated for patients with and without diabetes. The independent impact of diabetes on outcomes was evaluated after adjustment for outcome predictors. RESULTS: The prevalence of DM was 20% (N = 250). Diabetics were older and more often female. They were more likely to have hypertension, hyperlipoproteinemia, multivessel coronary disease and left main disease, and be obese. The primary net-clinical endpoint (EP) containing death, spontaneous nonfatal MI, stroke, severe bleeding, and revascularization at day 7 occurred in 6.1% of patients with, and in 3.5% of patients without DM (HR 1.8; 95% CI 0.978-3.315; P = 0.055). At one year, the key secondary endpoint defined as cardiovascular death, spontaneous MI, or stroke occurred in 8.8% with, and 5.5% without DM (HR 1.621; 95% CI 0.987-2.661; P = 0.054). In those with DM the risk of total one-year mortality (6.8% vs. 3.9% (HR 1.773; 95% CI 1.001-3.141; P = 0.047)) and the risk of nonfatal reinfarction (4.8% vs. 2.2% (HR 2.177; 95% CI 1.077-4.398; P = 0.026)) were significantly higher compared to in those without DM. There was no risk of major bleeding associated with DM (HR 0.861; 95% CI 0.554-1.339; P = 0.506). In the multivariate analysis, diabetes was independently associated with the one-year risk of reinfarction (HR 2.176; 95% Confidence Interval, 1.055-4.489; p = 0.035). CONCLUSION: Despite best practices STEMI treatment, diabetes is still associated with significantly worse prognoses, which highlights the importance of further improvements in the management of this high-risk population.

The prognostic significance of periprocedural infarction in the era of potent antithrombotic therapy. The PRAGUE-18 substudy.

BACKGROUND: The prognostic significance of periprocedural myocardial infarction (MI) remains controversial. METHODS AND RESULTS: The study aims to investigate the incidence of periprocedural MI in the era of high sensitivity diagnostic markers and intense antithrombotics, and its impact on early outcomes of patients with acute MI treated with primary angioplasty (pPCI). Data from the PRAGUE-18 (prasugrel versus ticagrelor in pPCI) study were analyzed. The primary net-clinical endpoint (EP) included death, spontaneous MI, stroke, severe bleeding, and revascularization at day 7. The key secondary efficacy EP included cardiovascular death, spontaneous MI, and stroke within 30 days. The incidence of peri-pPCI MI was 2.3% (N = 28) in 1230 study patients. The net-clinical EP occurred in 10.7% of patients with, and in 3.6% of patients without, peri-pPCI MI (HR 2.92; 95% CI 0.91-9.38; P = 0.059). The key efficacy EP was 10.7% and 3.2%, respectively (HR 3.44; 95% CI 1.06-11.13; P = 0.028). Patients with periprocedural MI were at a higher risk of spontaneous MI (HR 6.19; 95% CI 1.41-27.24; P = 0.006) and stent thrombosis (HR 10.77; 95% CI 2.29-50.70; P = 0.003) within 30 days. Age, hyperlipidemia, multi-vessel disease, post-procedural TIMI <3, pPCI on circumflex coronary artery, and periprocedural GP IIb/IIIa inhibitor were independent predictors of peri-pPCI MI. CONCLUSIONS: In the era of intense antithrombotic therapy, the occurrence of peri-pPCI MI is despite highly sensitive diagnostic markers a rare complication, and is associated with an increased risk of early reinfarction and stent thrombosis.

1-Year Outcomes of Patients Undergoing Primary Angioplasty for Myocardial Infarction Treated With Prasugrel Versus Ticagrelor.

BACKGROUND: Early outcomes of patients in the PRAGUE-18 (Comparison of Prasugrel and Ticagrelor in the Treatment of Acute Myocardial Infarction) study did not find any significant differences between 2 potent P2Y12 inhibitors. OBJECTIVES: The 1-year follow-up of the PRAGUE-18 study focused on: 1) a comparison of efficacy and safety between prasugrel and ticagrelor; and 2) the risk of major ischemic events related to an economically motivated post-discharge switch to clopidogrel. METHODS: A total of 1,230 patients with acute myocardial infarction (MI) treated with primary percutaneous coronary intervention were randomized to prasugrel or ticagrelor with an intended treatment duration of 12 months. The combined endpoint was cardiovascular death, MI, or stroke at 1 year. Because patients had to cover the costs of study medication after hospital discharge, some patients decided to switch to clopidogrel. RESULTS: The endpoint occurred in 6.6% of prasugrel patients and in 5.7% of ticagrelor patients (hazard ratio: 1.167; 95% confidence interval: 0.742 to 1.835; p = 0.503). No significant differences were found in: cardiovascular death (3.3% vs. 3.0%; p = 0.769), MI (3.0% vs. 2.5%; p = 0.611), stroke (1.1% vs. 0.7%; p = 0.423), all-cause death (4.7% vs. 4.2%; p = 0.654), definite stent thrombosis (1.1% vs. 1.5%; p = 0.535), all bleeding (10.9% vs. 11.1%; p = 0.999), and TIMI (Thrombolysis In Myocardial Infarction) major bleeding (0.9% vs. 0.7%; p = 0.754). The percentage of patients who switched to clopidogrel for economic reasons was 34.1% (n = 216) for prasugrel and 44.4% (n = 265) for ticagrelor (p = 0.003). Patients who were economically motivated to switch to clopidogrel had (compared with patients who continued the study medications) a lower risk of major cardiovascular events; however, they also had lower ischemic risk. CONCLUSIONS: Prasugrel and ticagrelor are similarly effective during the first year after MI. Economically motivated early post-discharge switches to clopidogrel were not associated with an increased risk of ischemic events. (Comparison of Prasugrel and Ticagrelor in the Treatment of Acute Myocardial Infarction [PRAGUE-18]; NCT02808767).

[Radiofrequency catheter ablation of atrial fibrillation performed under general anesthesia: results of a unicentric randomized trial]. / Radiofrekvencní katétrová ablace pro fibrilaci síní provádená v celkové anestezii: výsledky unicentrické randomizované studie.

INTRODUCTION: Radiofrequency catheter ablation (RFA) has recently become a routine part of atrial fibrillation (AF) treatment. The goal of our study was to determine whether the implementation of RFA of AF under general anesthesia (GA), compared to analgosedation (AS), will affect important characteristics of the ablation procedure, comfort of the patient and whether there is any clinical impact on the complication rate and the overall success of the procedure. METHODS: 50 patients with AF were randomized in a ratio of 1 : 1 into two groups for RFA in AS and in GA. Procedural characteristics, arrhythmia-free survival for the time of 12 months and subjective evaluation of pain tolerability of the procedure were monitored. RESULTS: Overall procedural times were comparable in GA and AS groups (111.2 ± 16.3 min vs 104.8 ± 25 min, p = NS). Time needed for preparation of patients was significantly longer in the GA group, while time needed for electrical disconnection of all pulmonary veins (PVs) was significantly shortened. Electrical isolation of the ipsilateral PVs after the last RF application was achieved in 94 % of lesions in GA and in 78 % of lesions in AS, respectively (p = 0.02). Shorter time of RF energy application to achieve electrical isolation of PVs was needed in the group of GA than in the group of AS (1 386 ± 387 s vs 1 745 ± 463 s, p = 0.005). Subjective discomfort evaluation of the procedure was more favorable in patients in the GA group. 88 % of patients in the GA group vs 68 % patients in AS (p = 0.1) had stable sinus rhythm off antiarrhythmic treatment during the 12 month period following the index procedure. While in the GA group all 3 patients with AF recurrence were willing to undergo another procedure in the GA, in the AS group only one patient out of 8 patients with AF recurrences underwent reablation. CONCLUSION: RFA of AF performed under GA provided improved tolerance and positive perception of the procedure, higher final treatment success and improved quality of life.Key words: general anesthesia - paroxysmal atrial fibrillation - pulmonary vein isolation - radiofrequency catheter ablation.

Prasugrel Versus Ticagrelor in Patients With Acute Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention: Multicenter Randomized PRAGUE-18 Study.

BACKGROUND: No randomized head-to-head comparison of the efficacy and safety of ticagrelor and prasugrel has been published in the 7 years since the higher efficacy of these newer P2Y12 inhibitors were first demonstrated relative to clopidogrel. METHODS: This academic study was designed to compare the efficacy and safety of prasugrel and ticagrelor in acute myocardial infarction treated with primary or immediate percutaneous coronary intervention. A total of 1230 patients were randomly assigned across 14 sites to either prasugrel or ticagrelor, which was initiated before percutaneous coronary intervention. Nearly 4% were in cardiogenic shock, and 5.2% were on mechanical ventilation. The primary end point was defined as death, reinfarction, urgent target vessel revascularization, stroke, or serious bleeding requiring transfusion or prolonging hospitalization at 7 days (to reflect primarily the in-hospital phase). This analysis presents data from the first 30 days (key secondary end point). The total follow-up will be 1 year for all patients and will be completed in 2017. RESULTS: The study was prematurely terminated for futility. The occurrence of the primary end point did not differ between groups receiving prasugrel and ticagrelor (4.0% and 4.1%, respectively; odds ratio, 0.98; 95% confidence interval, 0.55-1.73; P=0.939). No significant difference was found in any of the components of the primary end point. The occurrence of key secondary end point within 30 days, composed of cardiovascular death, nonfatal myocardial infarction, or stroke, did not show any significant difference between prasugrel and ticagrelor (2.7% and 2.5%, respectively; odds ratio, 1.06; 95% confidence interval, 0.53-2.15; P=0.864). CONCLUSIONS: This head-to-head comparison of prasugrel and ticagrelor does not support the hypothesis that one is more effective or safer than the other in preventing ischemic and bleeding events in the acute phase of myocardial infarction treated with a primary percutaneous coronary intervention strategy. The observed rates of major outcomes were similar but with broad confidence intervals around the estimates. These interesting observations need to be confirmed in a larger trial. CLINICAL TRIAL REGISTRATION: URL: http://www.ClinicalTrials.gov. Unique identifier: NCT02808767.

The incidence and outcomes of acute coronary syndromes in a central European country: results of the CZECH-2 registry.

BACKGROUND: The incidence and treatment strategies of acute coronary syndrome (ACS) vary by region. Additionally, the clinical spectrum of ACS is changing and outcomes are improving. AIM: We assessed the incidence, treatment strategies, and outcomes of ACS for a well-defined population within a well-established network of percutaneous coronary intervention (PCI) centers and non-PCI centers. METHODS: The CZECH-2 registry included 1221 consecutive patients (mean age: 68 ± 13 years; 63.4% males) admitted for suspected ACS to 32 hospitals (including 4 PCI centers) within four Czech counties (total population: 2,370,841 inhabitants) during a 2-month period. RESULTS: The estimated incidence of confirmed ACS was 2,149 cases/million/year. In 374 (31%) patients, ACS was ruled out during the hospital stay. Coronary angiography (CAG) was performed in 60% of the patients overall and PCI was performed in 59% of the confirmed ACS patients. Killip classifications II-IV on admission were more common in patients with final diagnosis of non ST-elevation myocardial infarction (NSTEMI) than ST-elevation myocardial infarction (STEMI) (37.1% vs. 22.8%; p<0.001). The 30-day mortality rate was 5.7% for the whole study group, 7.3% for STEMI patients, 8.4% for NSTEMI patients, and 1.6% for patients with unstable angina pectoris (UAP), respectively. CONCLUSIONS: Almost one-third of the patients admitted for suspected ACS had a different final diagnosis. Among those with confirmed ACS, the use of CAG, PCI, CABG, and effective medications is rational. Outcome in NSTEMI patients was equivalent to those in STEMI patients, mainly due to the high-risk population in this group.

Effect of platelet inhibition with cangrelor during PCI on ischemic events.

BACKGROUND: The intensity of antiplatelet therapy during percutaneous coronary intervention (PCI) is an important determinant of PCI-related ischemic complications. Cangrelor is a potent intravenous adenosine diphosphate (ADP)-receptor antagonist that acts rapidly and has quickly reversible effects. METHODS: In a double-blind, placebo-controlled trial, we randomly assigned 11,145 patients who were undergoing either urgent or elective PCI and were receiving guideline-recommended therapy to receive a bolus and infusion of cangrelor or to receive a loading dose of 600 mg or 300 mg of clopidogrel. The primary efficacy end point was a composite of death, myocardial infarction, ischemia-driven revascularization, or stent thrombosis at 48 hours after randomization; the key secondary end point was stent thrombosis at 48 hours. The primary safety end point was severe bleeding at 48 hours. RESULTS: The rate of the primary efficacy end point was 4.7% in the cangrelor group and 5.9% in the clopidogrel group (adjusted odds ratio with cangrelor, 0.78; 95% confidence interval [CI], 0.66 to 0.93; P=0.005). The rate of the primary safety end point was 0.16% in the cangrelor group and 0.11% in the clopidogrel group (odds ratio, 1.50; 95% CI, 0.53 to 4.22; P=0.44). Stent thrombosis developed in 0.8% of the patients in the cangrelor group and in 1.4% in the clopidogrel group (odds ratio, 0.62; 95% CI, 0.43 to 0.90; P=0.01). The rates of adverse events related to the study treatment were low in both groups, though transient dyspnea occurred significantly more frequently with cangrelor than with clopidogrel (1.2% vs. 0.3%). The benefit from cangrelor with respect to the primary end point was consistent across multiple prespecified subgroups. CONCLUSIONS: Cangrelor significantly reduced the rate of ischemic events, including stent thrombosis, during PCI, with no significant increase in severe bleeding. (Funded by the Medicines Company; CHAMPION PHOENIX ClinicalTrials.gov number, NCT01156571.).

Catheter ablation for paroxysmal atrial fibrillation: a randomized comparison between multielectrode catheter and point-by-point ablation.

INTRODUCTION: Catheter ablation for paroxysmal atrial fibrillation is widely used for patients with drug-refractory paroxysms of arrhythmia. Recently, novel technologies have been introduced to the market that aim to simplify and shorten the procedure. AIM: To compare the clinical outcome of pulmonary vein (PV) isolation using a multipolar circular ablation catheter (PVAC group), with point-by-point PV isolation using an irrigated-tip ablation catheter and the CARTO mapping system (CARTO group; CARTO, Biosense Webster, Diamond Bar, CA, USA). METHODS: Patients with documented PAF were randomized to undergo PV isolation using PVAC or CARTO. Atrial fibrillation (AF) recurrences were documented by serial 7-day Holter monitoring. RESULTS: One hundred and two patients (mean age 58 ± 11 years, 68 men) were included in the study. The patients had comparable baseline clinical characteristics, including left atrial dimensions and left ventricular ejection fraction, in both study arms (PVAC: n = 51 and CARTO: n = 51). Total procedural and fluoroscopic times were significantly shorter in the PVAC group (107 ± 31 minutes vs 208 ± 46 minutes, P < 0.0001 and 16 ± 5 minutes vs 28 ± 8 minutes, P < 0.0001, respectively). The AF recurrence was documented in 23% and 29% of patients in the PVAC and CARTO groups, respectively (P = 0.8), during the mean follow-up of 200 ± 13 days. No serious complications were noted in both study groups. CONCLUSIONS: Clinical success rates of PV isolation are similar when using multipolar circular PV ablation catheter and point-by-point ablation with a three-dimensional (3D) navigation system in patients with PAF, and results in shorter procedural and fluoroscopic times with a comparable safety profile.

Intravenous platelet blockade with cangrelor during PCI.

BACKGROUND: Intravenous cangrelor, a rapid-acting, reversible adenosine diphosphate (ADP) receptor antagonist, might reduce ischemic events during percutaneous coronary intervention (PCI). METHODS: In this double-blind, placebo-controlled study, we randomly assigned 5362 patients who had not been treated with clopidogrel to receive either cangrelor or placebo at the time of PCI, followed by 600 mg of clopidogrel. The primary end point was a composite of death, myocardial infarction, or ischemia-driven revascularization at 48 hours. Enrollment was stopped when an interim analysis concluded that the trial would be unlikely to show superiority for the primary end point. RESULTS: The primary end point occurred in 185 of 2654 patients receiving cangrelor (7.0%) and in 210 of 2641 patients receiving placebo (8.0%) (odds ratio in the cangrelor group, 0.87; 95% confidence interval [CI], 0.71 to 1.07; P=0.17) (modified intention-to-treat population adjusted for missing data). In the cangrelor group, as compared with the placebo group, two prespecified secondary end points were significantly reduced at 48 hours: the rate of stent thrombosis, from 0.6% to 0.2% (odds ratio, 0.31; 95% CI, 0.11 to 0.85; P=0.02), and the rate of death from any cause, from 0.7% to 0.2% (odds ratio, 0.33; 95% CI, 0.13 to 0.83; P=0.02). There was no significant difference in the rate of blood transfusion (1.0% in the cangrelor group and 0.6% in the placebo group, P=0.13), though major bleeding on one scale was increased in the cangrelor group, from 3.5% to 5.5% (P<0.001), because of more groin hematomas. CONCLUSIONS: The use of periprocedural cangrelor during PCI was not superior to placebo in reducing the primary end point. The prespecified secondary end points of stent thrombosis and death were lower in the cangrelor group, with no significant increase in the rate of transfusion. Further study of intravenous ADP blockade with cangrelor may be warranted. (ClinicalTrials.gov number, NCT00385138.)

The incidence, treatment strategies and outcomes of acute coronary syndromes in the "reperfusion network" of different hospital types in the Czech Republic: results of the Czech evaluation of acute coronary syndromes in hospitalized patients (CZECH) registry.

AIMS: To analyze the incidence, treatment strategies and outcomes of acute coronary syndromes (ACS) in Czech population. METHODS AND RESULTS: ACS diagnosis was confirmed in 1345 of 1921 (70%) consecutively admitted patients with suspected ACS. ACS incidence was 3248 cases/million/year and the annual incidence of confirmed myocardial infarction was 1960 per million. In-hospital mortality was 5.1% (10.0% with Q-MI, 4.4% with non-Q-MI, and 0.9% with UAP). Coronary angiography was performed in 92% of STEMI (followed by primary PCI in 83%, by CABG in 3%, by conservative therapy in 6%). Thrombolysis was used in only 1% of patients. Reperfusion therapy was thus used in 87% of all STEMI patients. Discharge medication included aspirin in 95%, a statin in 76%, a beta-blocker in 78%, an ACE inhibitor in 50%, clopidogrel in 60%, and ticlopidine in 4% of patients. CONCLUSIONS: In-hospital mortality of ACS in the Czech network of PCI and non-PCI hospitals is low. Nationwide application of primary PCI strategy for STEMI is feasible and increases the overall use of reperfusion therapy.

Prevalence of stress-induced myocardial stunning (Tako-Tsubo cardiomyopathy) among patients undergoing emergency coronary angiography for suspected acute myocardial infarction.

Stress-induced myocardial stunning is defined as a syndrome of acute chest pain, ST-T changes on the ECG and transient left ventricular apical wall motion abnormalities mimicking acute myocardial infarction but with surprisingly normal coronary angiography findings. The aim of this retrospective study is to assess the prevalence of stress-induced myocardial stunning among patients undergoing urgent coronary angiography for suspected acute myocardial infarction. During a four-year period (2002-2005), a total of 5876 patients underwent urgent coronary angiography for suspected acute myocardial infarction at three tertiary centers. Four patients fulfilled the diagnostic criteria for stress-induced myocardial stunning. Thus, the cath-lab prevalence of stress-induced myocardial stunning (i.e. among patients undergoing urgent coronary angiography for suspected acute myocardial infarction) was estimated as 1 per 1469 ST-elevation coronary angiograms (i.e. 0.07%) The estimated annual population incidence of this rare disorder was calculated as 0.00006%. Stress-induced myocardial stunning is an extremely rare syndrome among patients undergoing emergency coronary angiography for suspected acute myocardial infarction.