Relation of impaired Thrombolysis In Myocardial Infarction myocardial perfusion grades to residual thrombus following the restoration of epicardial patency in ST-elevation myocardial infarction

Clinical and angiographic data were analyzed from 929 patients who had ST-elevation myocardial infarction and open epicardial arteries after fibrinolytic therapy. Residual angiographically evident thrombus was associated with more frequent Thrombolysis In Myocardial Infarction (TIMI) grade 2 flow (33.6% vs 26.8%, p = 0.03), higher corrected TIMI frame counts (34 vs 31 frames, p = 0.0003), and lower TIMI myocardial perfusion grades (43.0% vs 32.0% TIMI myocardial perfusion grades 0/1, p = 0.001) among all patients and among patients who had TIMI grade 3 flow (33.5% vs 26.0% TIMI myocardial perfusion grades 0/1, p = 0.043). In multivariate analyses, angiographically evident thrombus was associated with higher corrected TIMI frame counts and worsened myocardial perfusion independent of clinical and angiographic covariates, including TIMI grade 3 flow.     

Association of lesion complexity following fibrinolytic administration with mortality in ST-elevation myocardial infarction

Greater lesion complexity, according to the American College of Cardiology and American Heart Association, has been associated with decreased success rates of percutaneous coronary intervention. We hypothesized that greater lesion complexity after fibrinolytic administration for ST-segment elevation myocardial infarction would similarly be associated with increased mortality and other adverse events at 30 days. We studies 2,605 patients from the Thrombolysis In Myocardial Infarction 10B and 14, Integrilin and Tenecteplase in Acute Myocardial Infarction, ENTIRE, and FASTER studies. For all studies, angiographic outcomes were assessed immediately after fibrinolytic administration and clinical outcomes were assessed at 30 days. Greater lesion complexity was associated with poorer epicardial flow and decreased myocardial perfusion at 60 minutes and after percutaneous coronary intervention and with a higher risk of shock and mortality within 30 days. In a multivariate model, type C lesion complexity remained associated with an increased 30-day mortality rate.     

Association of duration of symptoms at presentation with angiographic and clinical outcomes after fibrinolytic therapy in patients with ST-segment elevation myocardial infarction.

OBJECTIVES: We sought to determine if an underlying mechanism of the association between prolonged symptom-to-treatment times and adverse outcomes may be an association of symptom-to-treatment times with impaired Thrombolysis In Myocardial Infarction myocardial perfusion grades (TMPGs). BACKGROUND: Prolonged symptom duration among ST-segment elevation myocardial infarction (STEMI) patients undergoing fibrinolytic therapy is associated with adverse outcomes. METHODS: Angiography was performed 60 min after fibrinolytic administration in 3,845 Thrombolysis In Myocardial Infarction (TIMI) trial patients. RESULTS: The median time from symptom onset to treatment was longer among patients with impaired myocardial perfusion (3.0 h for TMPG 0/1 vs. 2.7 h for TMPG 2/3; p = 0.001). In a multivariate model, impaired tissue perfusion (TMPG 0/1) remained associated with increased time to treatment (odds ratio 1.14 per hour of delay; p = 0.007) even after adjusting for Thrombolysis In Myocardial Infarction flow grade (TFG) 3, left anterior descending infarct location, and baseline clinical characteristics. Impaired myocardial perfusion after rescue/adjunctive percutaneous coronary intervention (PCI) was associated with longer median times to treatment (3.0 h for TMPG 2/3 vs. 2.7 h for TMPG 0/1; p = 0.017), as was abnormal epicardial flow after rescue/adjunctive PCI (3.3 h for TFG 0/1/2 vs. 2.8 h for TFG 3; p = 0.005). Thirty-day mortality was associated with longer time from onset of symptoms to treatment (6.6% mortality for time to treatment >4 h vs. 3.3%; p < 0.001), even among patients undergoing rescue PCI. CONCLUSIONS: A prolonged symptom to treatment time among STEMI patients is associated with impaired myocardial perfusion independent of epicardial flow both immediately after fibrinolytic administration and after rescue/adjunctive PCI. These data provide a pathophysiologic link between prolonged symptoms due to vessel occlusion, impaired myocardial perfusion, and poor clinical outcomes.     

Association of peripheral neutrophilia with adverse angiographic outcomes in ST-elevation myocardial infarction

We hypothesized that absolute and relative neutrophilia would be associated with adverse angiographic outcomes in the 394 patient Limitation of Myocardial Infarction Following Thrombolysis in Acute Myocardial Infarction (LIMIT) Acute Myocardial Infarction (AMI) trial of fibrinolysis in ST-elevation myocardial infarction. The mean neutrophil count was 7.9 x 10(9)/L, with a mean neutrophil percentage of 72%. Patients with time from symptom onset to fibrinolytic treatment more than the median (2.7 hours) had a higher neutrophil count and percentage of neutrophils than patients with shorter time to treatment. Patients with a closed infarct-related artery at 90 minutes (Thrombolysis In Myocardial Infarction [TIMI] grade 0/1 flow) had higher neutrophil counts (8.8 +/- 3.8 vs 7.6 +/- 3.0, p = 0.02) but no difference in the percentage of neutrophils than patients with an open artery. Higher neutrophil counts were also mildly correlated with longer corrected TIMI frame counts (CTFC) in the infarct-related artery (r = 0.14, p = 0.02). Patients with impaired myocardial perfusion by TIMI myocardial perfusion grade (TMPG) had a greater percentage of neutrophils (73.2 +/- 10.7% for TMPG 0/1 vs 69.9 +/- 12.6% for TMPG 2/3, p = 0.047) but no detectable difference in neutrophil counts (8.2 +/- 3.3 vs 7.7 +/- 2.9, p = 0.24). There were no significant associations between other indexes in the cell differential and angiographic or clinical outcomes. Higher neutrophil counts remained independently associated with both closed arteries and CTFC in multivariable models controlling for age, left anterior descending artery infarct location, time to treatment, and pulse and blood pressure on admission. A greater percentage of neutrophils remained independently associated with impaired microvascular perfusion in a similar multivariable model. In patients with ST-elevation myocardial infarction, absolute and relative neutrophilia were associated with impaired epicardial and microvascular perfusion.     

Angiographic and clinical outcomes associated with direct versus conventional stenting among patients treated with fibrinolytic therapy for ST-elevation acute myocardial infarction

The present study reports outcomes of direct stenting versus conventional stenting, which was performed during adjunctive/rescue percutaneous coronary intervention (n = 556) in the Integrilin and Tenecteplase in Acute Myocardial Infarction trial, the Enoxaparin as Adjunctive Antithrombin Therapy for ST-Elevation Myocardial Infarction-Thrombolysis in Myocardial Infarction 23 trial, and the Fibrinolytic and Aggrastat ST-Elevation Resolution trial of fibrinolytic therapy in ST-elevation myocardial infarction. Direct stenting was associated with a lower rate of death, myocardial infarction, or congestive heart failure during hospitalization and at 30 days and was independently associated with improved in-hospital outcomes (odds ratio 0.44, 95% confidence interval 0.23 to 0.85, p = 0.014).     

Evaluation of the association of proximal coronary culprit artery lesion location with clinical outcomes in acute myocardial infarction

Impaired coronary artery blood flow and left anterior descending (LAD) artery culprit location are angiographic variables that have been associated with poorer outcomes after fibrinolytic administration in patients with acute myocardial infarction (AMI). We hypothesized that culprit lesion location in the proximal portion of the culprit artery would also be associated with poorer clinical outcomes compared with a mid or distal location. Lesion location and clinical outcomes were evaluated in 2,488 patients from the Thrombolysis In Myocardial Infarction (TIMI) 4, 10A, 10B, and 14 trials. Proximal lesions were located before or at the first major branch of the parent artery, mid lesions were between the first and the second major branches, and all other lesions were classified as distal. Proximal lesions were associated with a higher incidence of in-hospital death or recurrent AMI compared with mid or distal lesions (10.5% [n = 478] vs 6.1% [n = 1,498] vs 3.7% [n = 511], p <0.001), and they were associated with a higher rate of in-hospital death (6.7% [n = 478] vs 3.2% [n = 1,498] vs 2.5% [n = 511], p = 0.001). In a multiple logistic regression model adjusting for TIMI flow grade, age, gender, and pulse, the planimetered distance from the ostium to the LAD culprit lesion was associated with 30-day death or recurrent AMI (odds ratio 0.79 per centimeter increase in distance down the artery, p = 0.01). Proximal culprit lesion location is associated with an increased risk of adverse outcomes after fibrinolytic administration, which is likely due to a larger area of subtended myocardium. In patients with a LAD culprit lesion, proximal lesion location is a multivariate correlate of adverse outcomes even after adjustment for coronary blood flow and other covariates.     

Combined assessment of thrombolysis in myocardial infarction flow grade, myocardial perfusion grade, and ST-segment resolution to evaluate epicardial and myocardial reperfusion

The restoration of epicardial and myocardial flow remains the primary goal of reperfusion therapy in patients with ST-segment elevation myocardial infarction, but the optimal method to assess this goal has not been defined. Thrombolysis In Myocardial Infarction flow grade (TFG), myocardial perfusion grade (MPG), and ST-segment resolution (STRes) were combined to formulate a new measure of successful reperfusion in 649 patients who received pharmacologic reperfusion therapy in 3 recent phase II clinical trials of ST-segment elevation myocardial infarction. Coronary angiograms and electrocardiograms were analyzed at 60 minutes (before any intervention) after the initiation of reperfusion therapy. The complete restoration of perfusion, or the "trifecta," defined as the presence of TFG 3, MPG 3, and complete (> or =70%) STRes, occurred in 117 patients (18%). The achievement of this trifecta was associated with low rates of 30-day mortality (0% vs 3.9%, p = 0.02), congestive heart failure (CHF) (0.9% vs 7.1%, p = 0.01), and the combination of death or CHF (0.9% vs 10.7%, p = 0.001). When the results were stratified with respect to subsequent percutaneous coronary intervention (PCI) from 60 to 120 minutes, attainment of the trifecta at 60 minutes remained a strong predictor of better clinical outcomes, particularly in those patients who underwent early PCI. The achievement of TFG 3, MPG 3, and complete STRes at 60 minutes after fibrinolytic therapy and before PCI occurred in only 18% of patients but was associated with very low rates of death and CHF at 30 days. This new end point is proposed to evaluate the success of reperfusion therapy in patients who undergo early angiography.     

Association of a negative residual stenosis following rescue/adjunctive percutaneous coronary intervention with impaired myocardial perfusion and adverse outcomes among ST-segment elevation myocardial infarction patients

OBJECTIVES: We hypothesized that <0% residual stenosis (RS) after rescue/adjunctive percutaneous coronary intervention (PCI) following fibrinolytic administration in ST-segment elevation myocardial infarction (STEMI) would be associated with improved outcomes. BACKGROUND: Prior studies have associated larger lumen diameters after PCI with reduced rates of restenosis and target vessel revascularization. METHODS: Data were drawn from 748 patients with open epicardial arteries and with optimal luminal results (RS <20%) following rescue/adjunctive PCI after fibrinolytic administration in six STEMI trials. Patients were divided into two groups: 1) <0% RS and 2) 0% to 20% RS. RESULTS: A RS <0% was associated with greater gains in lumen diameter and smaller reference diameters after PCI (p < 0.001 for each), with a trend toward less frequent Thrombolysis In Myocardial Infarction flow grade (TFG) 3. A RS <0% was associated with a greater incidence of abnormal post-PCI Thrombolysis In Myocardial Infarction myocardial perfusion grades (TMPGs) (odds ratio 2.6 [1.2 to 5.9] for TMPG 0/1/2, p = 0.02), even when the analysis was restricted to patients with post-PCI TFG 3. CONCLUSIONS: A RS <0% following rescue/adjunctive PCI after fibrinolytic therapy for STEMI was independently associated with a reduction in the frequency of normal myocardial perfusion. Potential mechanisms of this finding include greater downstream embolization, increased stimulation of arterial stretch receptors with resultant coronary vasoconstriction, and increased vessel-wall injury after PCI. These findings suggest that additional prospective studies are needed to assess optimal RS that minimizes long-term restenosis without adverse effects.     

Association of Epicardial and Tissue-Level Reperfusion with Left Ventricular End-Diastolic Pressures in ST-Elevation Myocardial Infarction

Unfavorable hemodynamics among patients with ST-elevation myocardial infarction (STEMI) have been associated with adverse clinical outcomes and may be linked to a failure to achieve complete reperfusion. We hypothesized that impaired epicardial and tissue-level perfusion after fibrinolytic therapy would be associated with adverse hemodynamics. The relationship between left ventricular end-diastolic pressure (LVEDP), baseline clinical characteristics, and angiographic findings were examined in 666 patients with STEMI treated with fibrinolytic therapy from the TIMI 14, INTEGRITI (TIMI 20), ENTIRE (TIMI 23), and FASTER (TIMI 24) trials. LVEDP was analyzed as a dichotomous variable with an elevated LVEDP defined as LVEDP >18 mmHg (median value). Higher post-fibrinolytic LVEDP was associated with age > or = 65, female gender, Killip Class II-IV on presentation, and LAD culprit location. Elevated LVEDP was associated with both a closed infarct-related artery (58.8% of TIMI Flow Grade (TFG) 0/1 with elevated LVEDP vs. 46.6% of TFG 2/3, p = 0.03) and impaired myocardial perfusion (55.7% of TIMI Myocardial Perfusion Grade (TMPG) 0/1 with elevated LVEDP vs. 43.8% of TMPG 2/3, p = 0.02). In a multivariate analysis, impaired myocardial perfusion (OR 1.7, p = 0.02), abnormal Killip Class (OR 4.8, p = 0.001), age > or = 65 (OR 1.6, p = 0.04), and female gender (OR 1.9, p = 0.01) were independently associated with elevated LVEDP. Elevated LVEDP was independently associated with a greater incidence of in-hospital (OR 11.8, p = 0.02) and 30-day congestive heart failure (OR 4.4, p = 0.02). In STEMI, angiographic indices of incomplete reperfusion are associated with an elevated LVEDP, and elevated LVEDP is associated with adverse clinical outcomes.     

Effect of rescue or adjunctive percutaneous coronary intervention of the culprit artery after fibrinolytic administration on epicardial flow in nonculprit arteries

We hypothesized that blood flow in noninfarct arteries would improve after percutaneous coronary intervention of the culprit artery in the setting of ST-elevation myocardial infarction (STEMI). The corrected Thrombolysis In Myocardial Infarction (TIMI) frame count was measured in 94 patients (102 arteries) enrolled in the INTEGRITI, ENTIRE, and FASTER trials of reduced dose fibrinolytic and glycoprotein IIb/IIIa inhibition. The corrected TIMI frame count in nonculprit arteries improved by 3.4 +/- 13.4 frames after percutaneous coronary intervention but remained significantly slower than flow in normal arteries.     

Sequential risk stratification using TIMI risk score and TIMI flow grade among patients treated with fibrinolytic therapy for ST-segment elevation acute myocardial infarction

In the setting of ST-segment elevation myocardial infarction (STEMI), the Thrombolysis In Myocardial Infarction (TIMI) risk score (TRS) and indexes of epicardial and myocardial perfusion are associated with mortality. The association between TRS at presentation and angiographic indexes of epicardial and myocardial perfusion after reperfusion therapy has not been investigated. We hypothesized that TRS, TIMI flow grade (TFG), and TIMI myocardial perfusion grade (TMPG) would provide independent prognostic information and that angiographic indexes of poor flow and perfusion would be associated with a higher TRS. TRS and angiographic data were evaluated in 3,801 patients from the TIMI 4, 10A, 10B, 14, 20, 23, and 24 trials. Within each TRS stratum (TRS 0 to 2, 3 to 4, >/=5), 30-day mortality increased stepwise among patients with impaired TFG at 60 minutes after fibrinolytic administration. In a multivariate model adjusting for the TRS strata, impaired TMPG (0/1) was independently associated with higher mortality (odds ratio 2.28, p = 0.018). In a multivariate model adjusting for the TFG and infarct location, the likelihood of impaired TMPG (0/1) was greater among intermediate-risk (TRS 3 to 4) and high-risk (TRS >/=5) patients than among low-risk (TRS 0 to 2) patients (odds ratio 1.43, p = 0.019 and 1.50, p = 0.055, respectively). Thus, impaired epicardial flow and myocardial perfusion are independently associated with increased 30-day mortality among patients identified by TRS as high risk, although there is no synergism between either TFG or TMPG and TRS. High TRS at presentation is associated with abnormal myocardial perfusion, even after adjusting for possible confounders.     

How should we evaluate an open artery in STEMI patients?

Acute ST-elevation myocardial infarction (STEMI) is a majorcause of mortality and morbidity. After plaque rupture and intracoronarythrombus formation, ischaemia causes damage to myocytes andcoronary microcirculation soon after occlusion. In the 1980s,mortality reduction with thrombolytic therapy generated a newstandard of care for medical treatment of patients with STEMI.However, fibrinolytic therapy is limited by inadequate epicardialpatency, and subsequently it has been shown that mechanicalrevascularization of the infarct-related coronary artery offersan even greater clinical benefit to patients with STEMI. Thus,the goal of reperfusion treatment in patients with STEMI isto re-establish a patent infarct-related epicardial artery assoon as possible. The Thrombolysis In Myocardial Infarction (TIMI) group has categorizedepicardial coronary flow into four grades (0–3) to     

Angiographic characteristics of coronary disease and postresuscitation electrocardiograms in patients with aborted cardiac arrest outside a hospital

Postresuscitation electrocardiogram (ECG) in patients with aborted cardiac death may demonstrate ST-elevation myocardial infarction (STEMI), ST-T changes, intraventricular conduction delay, or other nonspecific findings. In the present study, we compared ECG to urgent coronary angiogram in 158 consecutive patients with STEMI and 54 patients not fulfilling criteria for STEMI admitted to our hospital from January 1, 2003 through December 31, 2008. At least 1 obstructive lesion was present in 97% of patients with STEMI and in 59% of patients without STEMI with ≥1 occlusion in 82% and 39%, respectively (p <0.001). Obstructive lesion was considered acute in 89% of patients with STEMI and in 24% of patients without STEMI (p <0.001). An acute lesion in STEMI had a higher thrombus score (2.6 vs 1.3, p = 0.05) and more often presented with Thrombolysis In Myocardial Infarction grade 0 to 1 flow (75% vs 36%, p <0.01). Percutaneous coronary intervention, which was attempted in 148 lesions in patients with STEMI and in 17 lesions in patients without STEMI, resulted in final Thrombolysis In Myocardial Infarction grade 3 flow in 87% and 71%, respectively (p = 0.34). In conclusion, STEMI on postresuscitation ECG is usually associated with the presence of an acute culprit lesion. However, in the absence of STEMI, an acute culprit lesion is still present in 1/4 of patients. An acute lesion in STEMI is more thrombotic and more often leads to complete occlusion. Urgent percutaneous coronary intervention is feasible and successful regardless of postresuscitation ECG.     

Relation of hyperemic epicardial flow to outcomes among patients with ST-segment elevation myocardial infarction receiving fibrinolytic therapy

In patients with ST-segment elevation myocardial infarction (STEMI), the restoration of normal epicardial flow following fibrinolytic administration is associated with improved clinical outcomes. The goal of this analysis was to examine the relation between hyperemic flow and outcomes following fibrinolytic administration for STEMI. In Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis In Myocardial Infarction 28 (CLARITY-TIMI 28), patients with STEMI (n=3,491) treated with fibrinolytic therapy were scheduled to undergo angiography 48 to 192 hours after randomization. Corrected TIMI frame count (CTFC) and TIMI myocardial perfusion grade (TMPG) were assessed, and their associations with outcomes at 30 days were evaluated. When evaluating initial angiography of the infarct-related artery, there was a nearly linear relation between CTFC and 30-day mortality, with faster flow (lower CTFC) associated with improved outcomes. Conversely, in patients who underwent percutaneous coronary intervention (PCI), very fast flow (CTFC<14) after intervention was associated with worse outcomes. Post-PCI hyperemic flow (CTFC<14) was associated with a higher incidence of mortality (p=0.056), recurrent myocardial infarction (p=0.011), and a composite of death or myocardial infarction (p<0.001) compared with normal flow (CTFC 14 to 28). When post-PCI CTFC was further stratified by TMPG, there was a U-shaped relation between mortality and CTFC in patients with poor myocardial perfusion (TMPG 0 or 1). This relation appeared to be linear in patients with TMPG 2 or 3. In conclusion, in patients who undergo PCI after fibrinolytic therapy for STEMI, hyperemic flow on coronary angiography is associated with an increased incidence of adverse outcomes. Hyperemic flow with associated impaired myocardial perfusion may be a marker of more extensive downstream microembolization.     

Association of a pulsatile blood flow pattern on coronary arteriography and short-term clinical outcomes in acute myocardial infarction

OBJECTIVES: We hypothesized that recognition of systolic flow reversal (pulsatile flow) after thrombolytic administration on coronary angiography is associated with angiographic and electrocardiogram findings reflecting impaired myocardial perfusion, as well as poorer clinical outcomes. BACKGROUND: Reversal of systolic flow on Doppler velocity wire recordings has been associated with impaired tissue perfusion on myocardial contrast echocardiography in the setting of myocardial infarction (MI). METHODS: Patients (n = 1,062) with a patent infarct-related artery were drawn from the Thrombolysis In Myocardial Infarction (TIMI) 10, TIMI 14, and Integrillin and Tenecteplase acute MI trials. RESULTS: Pulsatile flow (systolic flow reversal with cessation of antegrade contrast-dye motion or frank reversal of contrast-dye motion during systole) at 60 min after fibrinolytic administration was present in 11.0% of patients. Pulsatile flow was associated with higher corrected TIMI frame counts (slower epicardial flow) (median 40.1 frames, IQ 30 of 63 vs. 30 frames, interquartile 22 of 42, p < 0.0001), a closed microvasculature (TIMI myocardial perfusion grades 0 of 1, 57.1% vs. 37.8%, p = 0.03) and less complete (> or =70%) ST-segment resolution (23.5% vs. 58.9%, p = 0.008). Patients with pulsatile flow had a higher risk of death or reinfarction at 30 days (10.3% vs. 5.0%, p = 0.019). After controlling for age, pulse, blood pressure, anterior MI location, epicardial flow, and creatine kinase, pulsatile flow remained associated with an increased risk of death/MI (odds ratio 3.1, p = 0.006). CONCLUSIONS: A pulsatile pattern of flow is associated with impaired myocardial perfusion and poorer clinical outcomes independent of the velocity of antegrade flow in the epicardial artery. This simple and easily identifiable angiographic flow pattern may be useful in clinical risk stratification.     

High-Sensitivity C-Reactive Protein as a Predictor of Cardiovascular Events after ST-Elevation Myocardial Infarction

Background

The association between high-sensitivity C-reactive protein and recurrent major adverse cardiovascular events (MACE) in patients with ST-elevation myocardial infarction who undergo primary percutaneous coronary intervention remains controversial.

Objective

To investigate the potential association between high-sensitivity C-reactive protein and an increased risk of MACE such as death, heart failure, reinfarction, and new revascularization in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention.

Methods

This prospective cohort study included 300 individuals aged >18 years who were diagnosed with ST-elevation myocardial infarction and underwent primary percutaneous coronary intervention at a tertiary health center. An instrument evaluating clinical variables and the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores was used. High-sensitivity C-reactive protein was determined by nephelometry. The patients were followed-up during hospitalization and up to 30 days after infarction for the occurrence of MACE. Student''s t, Mann-Whitney, chi-square, and logistic regression tests were used for statistical analyses. P values of ≤0.05 were considered statistically significant.

Results

The mean age was 59.76 years, and 69.3% of patients were male. No statistically significant association was observed between high-sensitivity C-reactive protein and recurrent MACE (p = 0.11). However, high-sensitivity C-reactive protein was independently associated with 30-day mortality when adjusted for TIMI [odds ratio (OR), 1.27; 95% confidence interval (CI), 1.07-1.51; p = 0.005] and GRACE (OR, 1.26; 95% CI, 1.06-1.49; p = 0.007) risk scores.

Conclusion

Although high-sensitivity C-reactive protein was not predictive of combined major cardiovascular events within 30 days after ST-elevation myocardial infarction in patients who underwent primary angioplasty and stent implantation, it was an independent predictor of 30-day mortality.     

Comparison of effectiveness of primary angioplasty for proximal versus distal right coronary artery culprit lesion during acute myocardial infarction

From the cohort of 4,023 patients enrolled in the Primary Angioplasty for Myocardial Infarction (PAMI) trials, we pooled clinical, angiographic, and outcomes data on 1,521 patients with culprit lesions in the right coronary artery (RCA). We compared angiographic results, procedural complications, and in-hospital and 1-year clinical outcomes between patients with proximal RCA (n = 572) versus nonproximal RCA culprit lesions (n = 949). Patients with proximal RCA culprit lesions were older, had lower systolic blood pressure, greater diameter stenosis, and were less likely to have Thrombolysis In Myocardial Infarction (TIMI) 2 or 3 flow (19% vs 31%; p <0.0001) before percutaneous coronary intervention (PCI). After PCI, the incidence of TIMI 3 flow (94% vs 93%) was similar between groups. Patients with proximal RCA lesions were more likely to have bradyarrhythmias (30% vs 23%, p = 0.016) and require an intra-aortic balloon pump (IABP; 4.6% vs 2%, p = 0.034) during PCI. In-hospital complications, including mortality (2.3% vs 2.2%) and reinfarction (1.4% vs 1.1%), and the 1-year incidence of death, reinfarction, ischemia driven target vessel revascularization, and major adverse cardiovascular events were similar between groups. After adjustment for baseline differences, proximal RCA location of the culprit lesion was independently associated with greater IABP use (odds ratio 2.41, 95% confidence interval 1.04 to 5.58) but not with bradyarrhythmias during PCI. Thus, in patients with acute myocardial infarction referred for primary angioplasty, proximal RCA location of the culprit lesion is associated with excellent clinical outcomes that are similar to nonproximal RCA lesions.     

Diabetes mellitus, myocardial reperfusion, and outcome in patients with acute ST-elevation myocardial infarction treated with primary angioplasty (from HORIZONS AMI)

Diabetes mellitus (DM) increases mortality in acute ST-segment elevation myocardial infarction (STEMI) but the responsible mechanism is not fully elucidated. We compared the rate of successful myocardial reperfusion measured by tissue myocardial perfusion grade (TMPG) and outcomes in patients with and without DM undergoing primary percutaneous coronary intervention (PCI) for STEMI. Patients enrolled in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS AMI) trial were analyzed according to presence of DM with respect to TMPG after PCI and outcomes at 30 days and 3 years. Multivariable logistic regression was performed to identify the independent contribution to mortality of DM and TMPG and the interaction between the 2 was assessed. Complete data were available for 3,265 patients, of whom 533 (16.3%) had DM. Diabetic patients were significantly older and heavier and had more risk factors for coronary disease and more previous MI, revascularization, and heart failure. There were no differences in rates of Thrombolysis In Myocardial Infarction grade 3 flow after PCI in the infarct artery or TMPG 2/3 between patients with and without DM. Compared to nondiabetics, mortality was significantly higher at 30 days and at 3 years in the DM group (1.8% vs 4.5%, p = 0.0002 and 5.4% vs 11.0%, p <0.0001, respectively). DM and TMPG were significantly associated with 3-year mortality, but there was no statistical interaction between DM and TMPG (p = 0.70). In conclusion, DM is associated with a significantly higher risk of death but this association is not mediated by impaired epicardial or myocardial reperfusion.     

Clinical and electrocardiographic correlates of normal coronary angiography in patients referred for primary percutaneous coronary intervention

This study sought to determine the prevalence as well as clinical and electrocardiographic correlates of patients referred for primary percutaneous coronary intervention (PCI) who had angiographically normal coronary arteries. Data for 690 consecutive patients with ST-elevation myocardial infarction (STEMI) referred for primary PCI within a metropolitan area health service were reviewed. Characteristics of patients with angiographically normal coronary arteries (n = 87; 13%) were compared with patients with angiographically shown culprit lesions (control group; n = 594). Nine patients with significant coronary disease, but no identifiable culprit lesion, were excluded. Electrocardiograms (ECGs) from both groups were reviewed by 2 cardiologists blinded to angiographic findings. Patients in the normal coronaries group were younger and had fewer risk factors. On expert review of ECGs, 55% of patients in the normal coronaries group had ST-elevation criteria for STEMI (vs 93% in the control group; p <0.001), but the ECG was considered consistent with a diagnosis of STEMI by both observers in only 33% (vs 92% in the control group; p <0.001). Left branch bundle block independently correlated with normal coronary arteries on multivariate analysis (odds ratio for STEMI 0.016, 95% confidence interval 0.004 to 0.064, p <0.001). The discharge diagnosis in the normal coronaries group was predominantly pericarditis (n = 72; 83%). In conclusion, the prevalence of angiographically normal coronary arteries in patients referred for primary PCI was 13%. Electrocardiographic correlation suggested that this can be reduced by adherence to conventional electrocardiographic criteria for STEMI diagnosis and review of ECGs by experienced clinicians.     

Early and long-term clinical outcomes associated with reinfarction following fibrinolytic administration in the Thrombolysis in Myocardial Infarction trials

OBJECTIVES: We hypothesized that early recurrent myocardial infarction (MI) following fibrinolytic administration would be assessed with higher mortality at both 30 days and 2 years. BACKGROUND: Although early recurrent MI after fibrinolytic therapy has been associated with increased early mortality in the acute MI setting, its relation to long-term mortality has not been fully explored. METHODS: Mortality data were ascertained in 20,101 patients enrolled in the Thrombolysis In Myocardial Infarction (TIMI) 4, 9, and 10B and Intravenous NPA for the Treatment of Infarcting Myocardium Early (InTIME-II) acute MI trials. RESULTS: The frequency of symptomatic recurrent MI during the index hospitalization was 4.2% (836/20,101). Recurrent MI during the index hospital period was associated with increased 30-day mortality (16.4% [137/836] vs. 6.2% [1,188/19,260], p < 0.001). Likewise, recurrent MI was associated with a sustained increase in mortality up to two years, even after adjustments were made for covariates known to be associated with mortality and recurrent MI (hazard ratio 2.11, p < 0.001). However, this higher mortality at 2 years was due to an early divergence in mortality by 30 days and was not due to a significant increase in late mortality between 30 days and 2 years (4.38% [31/707] vs. 3.76% [685/18,206], p = NS). Percutaneous coronary intervention during the index hospitalization was associated with a lower rate of in-hospital recurrent MI (1.6% vs. 4.5%, p < 0.001) and lower two-year mortality (5.6% vs. 11.6%, p < 0.001). Performance of coronary artery bypass graft surgery was also associated with a lower recurrent rate of MI (0.7% vs. 4.3%, p < 0.001) and lower two-year mortality rate (7.95% vs. 10.6%, p = 0.0008). CONCLUSIONS: Early recurrent MI is associated with increased mortality up to two years. However, most deaths occur early, and the risk of additional deaths between the index hospital period and two years was not significantly increased among patients with recurrent MI. Percutaneous coronary intervention during the index hospitalization was associated with a lower risk of recurrent MI and a lower risk of two-year mortality.