Prospective Evaluation of Clinical Outcomes After Acute ST-Elevation Myocardial Infarction in Patients Who Are Ineligible for Reperfusion Therapy: Preliminary Results From the TETAMI Registry and Randomized Trial

Nicotinamide Riboside Supplementation Restores Myocardial Nicotinamide Adenine Dinucleotide Levels, Improves Survival, and Promotes Protective Environment Post Myocardial Infarction

AIMS

Myocardial infarction (MI) is a major cause of death. Nicotinamide adenine dinucleotide (NAD+) is a coenzyme in oxidative phosphorylation and substrate of sirtuins and poly-ADP ribose polymerases, enzymes critical for cardiac remodeling post-MI. Decreased NAD+ is reported in several heart failure models with paradoxically an upregulation of nicotinamide riboside kinase 2, which uses nicotinamide riboside (NR) as substrate in an NAD+ biosynthetic pathway. We hypothesized that stimulating nicotinamide riboside kinase 2 pathway by NR supplementation exerts cardioprotective effects.

METHODS AND RESULTS

MI was induced by LAD ligation in 2-3-month-old male mice. NR was administered daily (1 µmole/g body weight) over 7 days. RT-PCR showed a 60-fold increase in nicotinamide riboside kinase 2 expression 4 days post-MI with a 60% drop in myocardial NAD+ and overall survival of 61%. NR restored NAD+ levels and improved survival to 92%. Assessment of respiration in cardiac fibers revealed mitochondrial dysfunction post-MI, and NR improved complexes II and IV activities and citrate synthase activity, a measure of mitochondrial content. Additionally, NR reduced elevated PARP1 levels and activated a type 2 cytokine milieu in the damaged heart, consistent with reduced early inflammatory and pro-fibrotic response.

CONCLUSION

Our data show that nicotinamide riboside could be useful for MI management.

Coronary Intervention in ST-Segment Elevation Myocardial Infarction Patients With Symptom Onset >12 Hours: Data from China Acute Myocardial Infarction Registry

To determine whether late percutaneous coronary intervention (PCI) of an infarct-related artery >12 h after ST-segment elevation myocardial infarction onset is beneficial, patients were included from the prospective, nationwide, multicenter China Acute Myocardial Infarction registry. The number of patients who underwent PCI or received drug therapy alone was 4791 and 1149, respectively. Hazard ratio (HR) and associated 95% confidence interval (CI) were calculated. Compared with drug therapy, PCI was associated with lower incidences of 2-year major adverse cardiac and cerebrovascular events (MACCE; 6.43 vs 20.19%; HR, .27; 95% CI, .23-.32; P < .001), all-cause death (4.13 vs 15.74%; HR, .24; 95% CI, .20-.30; P < .001), myocardial infarction (1.73 vs 3.31%; HR, .49; 95% CI, .33-.72; P = .0003), stroke (1.02 vs 2.00%; HR, .47; 95% CI, .28-.77; P = .0026), and revascularization (10.96 vs 27.56%; HR, .32; 95% CI, .26-.39; P < .001). Subgroup analysis consistently indicated that PCI was superior to drug therapy. Moreover, the left ventricular ejection fraction in the PCI group was increased after 2-year follow-up, whereas there was no significant increase in the drug therapy group. In conclusion, late PCI is common in Chinese clinical practice, and it is associated with significant improvements in cardiac function and survival compared with drug therapy alone.

Effect of Rivaroxaban vs Enoxaparin on Major Cardiac Adverse Events and Bleeding Risk in the Acute Phase of Acute Coronary Syndrome: The H-REPLACE Randomized Equivalence and Noninferiority Trial

IMPORTANCE

Parenteral enoxaparin is a preferred anticoagulant used in the acute phase for patients with acute coronary syndrome (ACS). The safety and efficacy of short-term low-dose rivaroxaban in this clinical setting remain unknown.

OBJECTIVE

To compare the safety and efficacy of rivaroxaban vs enoxaparin in the acute phase of ACS.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, prospective, open-label, active-controlled, equivalence and noninferiority trial was conducted from January 2017 through May 2021 with a 6-month follow-up at 21 hospitals in China. Participants included patients with ACS missing the primary reperfusion window or before selective revascularization. Data were analyzed from November 2021 to November 2022.

INTERVENTIONS

Participants were randomized 1:1:1 to oral rivaroxaban 2.5 mg or 5 mg or 1 mg/kg subcutaneous enoxaparin twice daily in addition to dual antiplatelet therapy (DAPT; aspirin 100 mg and clopidogrel 75 mg once daily) for a mean of 3.7 days.

MAIN OUTCOMES AND MEASURES

The primary safety end point was bleeding events, as defined by the International Society on Thrombosis and Haemostasis, and the primary efficacy end point was major adverse cardiovascular events (MACEs), including cardiac death, myocardial infarction, rerevascularization, or stroke during the 6-month follow-up.

RESULTS

Of 2055 enrolled patients, 2046 (99.6%) completed the trial (mean [SD] age 65.8 [8.2] years, 1443 [70.5%] male) and were randomized to enoxaparin (680 patients), rivaroxaban 2.5 mg (683 patients), or rivaroxaban 5 mg (683 patients). Bleeding rates were 46 patients (6.8%) in the enoxaparin group, 32 patients (4.7%) in the rivaroxaban 2.5 mg group, and 36 patients (5.3%)in the rivaroxaban 5 mg group (rivaroxaban 2.5 mg vs enoxaparin: noninferiority hazard ratio [HR], 0.68; 95% CI, 0.43 to 1.07; P = .005; rivaroxaban 5 mg vs enoxaparin: noninferiority HR, 0.88; 95% CI, 0.70 to 1.09; P = .001). The incidence of MACEs was similar among groups, and noninferiority was reached in the rivaroxaban 5 mg group (HR, 0.60; 95% CI, 0.31 to 1.16, P = .02) but not in the rivaroxaban 2.5 mg group (HR, 0.68; 95% CI, 0.36 to 1.30; P = .05) compared with the enoxaparin group.

CONCLUSIONS AND RELEVANCE

In this equivalence and noninferiority trial, oral rivaroxaban 5 mg showed noninferiority to subcutaneous enoxaparin (1 mg/kg) for patients with ACS treated with DAPT during the acute phase. Results of this feasibility study provide useful information for designing future randomized clinical trials with sufficient sample sizes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03363035.

Identification and validation of senescence-related genes in circulating endothelial cells of patients with acute myocardial infarction

Background

Acute myocardial infarction (AMI) is the main clinical cause of death and cardiovascular disease and thus has high rates of morbidity and mortality. The increase in cardiovascular disease with aging is partly the result of vascular endothelial cell senescence and associated vascular dysfunction. This study was performed to identify potential key cellular senescence-related genes (SRGs) as biomarkers for the diagnosis of AMI using bioinformatics.

Methods

Using the CellAge database, we identified cellular SRGs. GSE66360 and GSE48060 for AMI patients and healthy controls and GSE19322 for mice were downloaded from the Gene Expression Omnibus (GEO) database. The GSE66360 dataset was divided into a training set and a validation set. The GSE48060 dataset was used as another validation set. The GSE19322 dataset was used to explore the evolution of the screened diagnostic markers in the dynamic process of AMI. Differentially expressed genes (DEGs) of AMI were identified from the GSE66360 training set. Differentially expressed senescence-related genes (DESRGs) selected from SRGs and DEGs were analyzed using Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and protein-protein interaction (PPI) networks. Hub genes in DESRGs were selected based on degree, and diagnostic genes were further screened by gene expression and receiver operating characteristic (ROC) curve. Finally, a miRNA-gene network of diagnostic genes was constructed and targeted drug prediction was performed.

Results

A total of 520 DEGs were screened from the GSE66360 training set, and 279 SRGs were identified from the CellAge database. The overlapping DEGs and SRGs constituted 14 DESRGs, including 4 senescence suppressor genes and 10 senescence inducible genes. The top 10 hub genes, including FOS, MMP9, CEBPB, CDKN1A, CXCL1, ETS2, BCL6, SGK1, ZFP36, and IGFBP3, were screened. Furthermore, three diagnostic genes were identified: MMP9, ETS2, and BCL6. The ROC analysis showed that the respective area under the curves (AUCs) of MMP9, ETS2, and BCL6 were 0.786, 0.848, and 0.852 in the GSE66360 validation set and 0.708, 0.791, and 0.727 in the GSE48060 dataset. In the GSE19322 dataset, MMP9 (AUC, 0.888) and ETS2 (AUC, 0.929) had very high diagnostic values in the early stage of AMI. Finally, based on these three diagnostic genes, we found that drugs such as acetylcysteine and genistein may be targeted for the treatment of age-related AMI.

Conclusion

The results of this study suggest that cellular SRGs might play an important role in AMI. MMP9, ETS2, and BCL6 have potential as specific biomarkers for the early diagnosis of AMI.

Sex differences in cardiac remodeling post myocardial infarction with acute cigarette smoking

Background

Whether cigarette smoking affects the heart post-myocardial infarction (MI) in a sex-dependent way remains controversial. Using a mouse model, we investigated cardiac remodeling under the influence of acute cigarette smoke (CS) exposure following ischemic injury in both sexes.

Methods

Ten cigarettes were smoked twice daily for 2 weeks followed by MI and then 1 additional week post permanent LAD ligation. Cardiac function, histology, and infarct size were assessed, and inflammatory markers quantified by RT–PCR. Statistical comparisons were performed using an unpaired t test or ANOVA followed by Tukey post hoc test.

Results

We observed that cigarette smoking exacerbated both left and right ventricular remodeling only in males at an early stage of post-MI. Females did not display a significant structural and/or functional alteration within 7 days of cardiac remodeling post-MI upon CS exposure. Worsened right ventricular remodeling in males was independent of pulmonary congestion. CS-exposed males exhibited enhanced increases in left ventricular end systolic and diastolic volumes, as well as reductions in ejection fraction and fractional area changes of left ventricular base. At day 7, infarct size was increased by cigarette smoking in males only, which was accompanied by enhanced collagen deposition in both the infarcted and peri-infarcted areas. Both IL-6 and TNF-α mRNA expression significantly increased in CS-exposed MI male group only at day 7 post-MI suggestive of prolonged inflammation.

Conclusions

These findings indicate that CS exposure worsens the progression of cardiac remodeling post-MI in male sex in a significant manner compared to female sex at least at early stages.

Late Percutaneous Coronary Intervention is Associated with Better Prognosis of Patients with Acute Myocardial Infarction

Background

The optimal timing of invasive coronary revascularization in patients with late presentation of acute myocardial infarction (AMI) remains unclear.

Objective

This study aimed to investigate whether late percutaneous coronary intervention (PCI) is associated with the prognosis of AMI patients with HFpEF presenting >24h after symptom onset.

Methods

We enrolled 680 AMI patients with HFpEF. Patients were divided into 3 groups: early-PCI strategy (defined as the time to open IRA from symptom onset <24 h), late-PCI strategy (defined as the time of PCI-mediated reperfusion was >24 h) and non-revascularization group.

Results

A total of 144 (21.2%) experienced a MACE, including 118 (17.4%) all-cause deaths and 26 (3.8%) re-hospitalization for HF during a follow-up period of 30.20±15.62 months. After adjusting for gender, age, smoking, diabetes mellitus, NT-proBNP and eGFR, late-PCI was a significant and independent predictor of MACE (hazard ratio 0.367; 95% confidence interval 0.202–0.665; p<0.001). Kaplan–Meier analysis showed that late-PCI decreased cumulative risk of MACE (p< 0.001).

Conclusion

Late-PCI and early-PCI strategies are associated with a reduced risk of MACE in AMI patients with HFpEF presenting >24 h after symptom onset, compared to conservative strategies.

The use of reperfusion therapy in transition countries without fully applicable pharmacoinvasive strategy

Background/Aim. The pharmacoinvasive (PI) therapy is a recommended strategy in patients (pts) with ST elevation myocardial infarction (STEMI) unable to undergo timely primary percutaneous coronary intervention (p-PCI). The aim of the study was to find out the cohorts of pts who are not treated by any reperfusion therapy (RT) as well to determine the outcome of the pts treated with RT in a transition country without fully applicable PI therapy. Methods. The study analyzed data from the Hospital National Registry for Acute Coronary Syndrome of Serbia (HORACS). Results. The significant predictors of the withdrawing of the application of any RT in the model [c 75.6%, SE 0.004, 95% CI 0.748?0.761)] were a ge ( ? 6 5 years), heart failure (Killip II-IV), diabetes mellitus, and the time to first medical contact (FMC) (> 360 min). In patients without RT, mortality was 15.7%, in pts treated with fibrinolytic therapy (FT) was 10.5%, and in pts treated with pPCI, it was 6.2% (p < 0.000). Within 3 hours to FMC, higher in-hospital mortality was in FT pts (FT 8.7% vs p-PCI 4.3%). FT treated patients were older, had more comorbidities and heart failure (HF). However, after propensity score matching, in order to ad-just the differences among the pts, the mortality rate remained higher in FT pts but not statistically significantly higher than in p-PCI pts (FT 8.8% vs p-PCI 6.4%). Conclusion. The balance of the best cost-benefit strategies for better use of RT is difficult to achieve in transition countries. The possibility for timely p-PCI and PI therapy is especially not applicable in high-risk patients, older pts, pts with HF, and those with diabetes mellitus.

Identification of Featured Metabolism-Related Genes in Patients with Acute Myocardial Infarction

Objective

A growing body of emerging evidence indicates that metabolic processes play a pivotal role in the biological processes underlying acute myocardial infarction (AMI). The aim of the current study was to identify featured metabolism-related genes in patients with AMI using a support vector machine (SVM) and to further explore the value of these genes in the diagnosis of AMI.

Methods

Gene microarray expression data related to AMI were downloaded from the GSE66360 dataset in the Gene Expression Omnibus (GEO) database. This data set consisted of 50 AMI samples and 49 normal controls that were randomly classified into a discovery cohort (21 AMI samples and 22 normal controls) and a validation cohort (28 AMI and 28 normal controls). We applied a machine learning method that combined SVM with recursive feature elimination (RFE) to discriminate AMI patients from normal controls. Based on this, an SVM classifier was constructed. Receiver operating characteristic (ROC) analysis was used to investigate the predictive value for the early diagnosis of AMI in the two cohorts and was then further verified in an independent external cohort.

Results

Three metabolism-related genes were identified based on SVM-RFE (AKR1C3, GLUL, and PDE4B). The SVM classifier based on the three genes allowed for excellent discrimination between AMI and healthy samples in both the discovery cohort (AUC = 0.989) and the validation cohort (AUC = 0.964), and this was further confirmed in the GSE68060 dataset (AUC = 0.839). Additionally, the SVM classifier allowed for perfect discrimination between recurrent AMI events and nonrecurrent events in the GSE68060 cohort (AUC = 0.992). GO and KEGG pathway enrichment analysis of the identified featured genes revealed significant enrichment of specific metabolic pathways.

Conclusion

The identified metabolism-related genes may play important roles in the development of AMI and may represent diagnostic and therapeutic biomarkers of AMI.

Identifying key genes associated with acute myocardial infarction

BACKGROUND

This study aimed to identify key genes associated with acute myocardial infarction (AMI) by reanalyzing microarray data.

METHODS

Three gene expression profile datasets GSE66360, GSE34198, and GSE48060 were downloaded from GEO database. After data preprocessing, genes without heterogeneity across different platforms were subjected to differential expression analysis between the AMI group and the control group using metaDE package. P < .05 was used as the cutoff for a differentially expressed gene (DEG). The expression data matrices of DEGs were imported in ReactomeFIViz to construct a gene functional interaction (FI) network. Then, DEGs in each module were subjected to pathway enrichment analysis using DAVID. MiRNAs and transcription factors predicted to regulate target DEGs were identified. Quantitative real-time polymerase chain reaction (RT-PCR) was applied to verify the expression of genes.

RESULT

A total of 913 upregulated genes and 1060 downregulated genes were identified in the AMI group. A FI network consists of 21 modules and DEGs in 12 modules were significantly enriched in pathways. The transcription factor-miRNA-gene network contains 2 transcription factors FOXO3 and MYBL2, and 2 miRNAs hsa-miR-21-5p and hsa-miR-30c-5p. RT-PCR validations showed that expression levels of FOXO3 and MYBL2 were significantly increased in AMI, and expression levels of hsa-miR-21-5p and hsa-miR-30c-5p were obviously decreased in AMI.

CONCLUSION

A total of 41 DEGs, such as SOCS3, VAPA, and COL5A2, are speculated to have roles in the pathogenesis of AMI; 2 transcription factors FOXO3 and MYBL2, and 2 miRNAs hsa-miR-21-5p and hsa-miR-30c-5p may be involved in the regulation of the expression of these DEGs.

Predictors of non-invasive therapy and 28-day-case fatality in elderly compared to younger patients with acute myocardial infarction: an observational study from the MONICA/KORA Myocardial Infarction Registry

Background

A substantial proportion of patients with acute myocardial infarction (AMI) did not receive invasive therapy, defined as percutaneous coronary intervention and/or coronary artery bypass grafting. Aims of this study were to evaluate predictors of non-invasive therapy in elderly compared to younger AMI patients and to assess the association between invasive therapy and 28-day-case fatality.

Methods

From the German population-based registry, 3475 persons, consecutively hospitalized with an AMI between 2009 and 2012 were included. Data were collected by standardized interviews and chart review. All-cause mortality was assessed on a regular basis. Multivariable logistic regression analyses were conducted.

Results

The sample consisted of 1329 patients aged 28–65 years (age category [AC] 1), 1083 aged 65–74 years (AC 2), and 1063 aged 75–84 years (AC 3). The proportion of patients receiving non-invasive therapy was 10.7, 17.7, and 35.8 % in AC 1, 2, and 3, respectively. Predictors of non-invasive therapy in all ACs were non-ST segment elevation MI, bundle branch block, reduced left ventricular ejection fraction, prior stroke, absence of hyperlipidemia, and low creatine kinase. Elderly women (≥65 years) were less likely to receive invasive therapy. Stratifying the models by type of AMI revealed fewer predictors in patients with ST segment elevation MI. Regarding 28-day-case fatality, strong inverse relations with invasive therapy were seen in all AC: odds ratio of 0.35 (95 % confidence interval [CI] 0.15–0.84), 0.45 (95 % CI 0.22–0.92), and 0.39 (95 % CI 0.24–0.63) in AC 1, 2 and 3, respectively.

Conclusion

In today’s real-life patient care we found that predictors of non-invasive therapy were predominantly the same in all age groups, but differed particularly by type of AMI. Further research is necessary to investigate the real reasons for non-invasive therapy, especially among elderly women. Moreover, we confirmed that receiving invasive therapy was inversely associated with 28-day-case fatality independent of age.

Cost-effectiveness of a European ST-segment elevation myocardial infarction network: results from the Catalan Codi Infart network

OBJECTIVES

To evaluate the cost-effectiveness of the ST-segment elevation myocardial infarction (STEMI) network of Catalonia (Codi Infart).

DESIGN

Cost-utility analysis.

SETTING

The analysis was from the Catalonian Autonomous Community in Spain, with a population of about 7.5 million people.

PARTICIPANTS

Patients with STEMI treated within the autonomous community of Catalonia (Spain) included in the IAM CAT II-IV and Codi Infart registries.

OUTCOME MEASURES

Costs included hospitalisation, procedures and additional personnel and were obtained according to the reperfusion strategy. Clinical outcomes were defined as 30-day avoided mortality and quality-adjusted life-years (QALYs), before (N=356) and after network implementation (N=2140).

RESULTS

A substitution effect and a technology effect were observed; aggregate costs increased by 2.6%. The substitution effect resulted from increased use of primary coronary angioplasty, a relatively expensive procedure and a decrease in fibrinolysis. Primary coronary angioplasty increased from 31% to 89% with the network, and fibrinolysis decreased from 37% to 3%. Rescue coronary angioplasty declined from 11% to 4%, and no reperfusion from 21% to 4%. The technological effect was related to improvements in the percutaneous coronary intervention procedure that increased efficiency, reducing the average length of the hospital stay. Mean costs per patient decreased from €8306 to €7874 for patients with primary coronary angioplasty. Clinical outcomes in patients treated with primary coronary angioplasty did not change significantly, although 30-day mortality decreased from 7.5% to 5.6%. The incremental cost-effectiveness ratio resulted in an extra cost of €4355 per life saved (30-day mortality) and €495 per QALY. Below a cost threshold of €30,000, results were sensitive to variations in costs and outcomes.

CONCLUSIONS

The Catalan STEMI network (Codi Infart) is cost-efficient. Further studies are needed in geopolitical different scenarios.

Cyclosporin A in left ventricular remodeling after myocardial infarction

Recent studies suggest that an increase in apoptosis within the myocardium may be a contributing factor for the progression of late adverse left ventricular (LV) remodeling following myocardial infarction (MI). Given that apoptosis is often triggered by induction of the mitochondrial permeability transition (MPT) pore, the goal of this study was to evaluate the therapeutic efficacy of cyclosporin A (CsA), an MPT blocker, to prevent cells from undergoing apoptosis and consequently attenuate late LV remodeling post-MI. MI was induced in C57BL/6 mice and then randomized to either vehicle or CsA groups. Beginning 48 h after surgery after infarction had already occurred, mice were gavaged with CsA (2 mg/kg) or vehicle once daily. LV end-diastolic volume and LV ejection fraction were assessed by echocardiography before MI induction and terminally at either 7 days (n = 7) or 28 days (n = 8) post-MI. LV end-diastolic volume increased and LV ejection fraction decreased in all MI groups with no difference between the CsA-treated and untreated groups. After vehicle and CsA, areas of necrosis were present at 7 and 28 days post-MI with no difference between treatment groups. Caspase-3 activity and terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling in distal nonnecrotic LV both increased after MI but were lower in CsA-treated mice compared with vehicle (P < 0.05). In conclusion, CsA decreased apoptosis occurring late after MI, confirming involvement of a CsA-sensitive MPT in the cell death. However, CsA-mediated reduction in apoptosis in non-MI myocardium was not beneficial against late pump dysfunction occurring during post-MI remodeling.

Would tirofiban have been shown non-inferior to abciximab had the TENACITY trial not been terminated for financial reasons?

OBJECTIVES

To investigate whether tirofiban would have been non-inferior to abciximab had the trial completed enrollment and place the termination of this trial in a broader research ethics context.

BACKGROUND

TENACITY was terminated by the sponsor for financial reasons. At the time, event rates for the 2 treatment arms were unknown.

METHODS

TENACITY was designed to compare tirofiban with abciximab in approximately 8,000 patients; however, enrollment was terminated after 383 (4.8%) patients. The primary end-point was a composite of 30-day death, myocardial infarction, and urgent target vessel revascularization. Non-inferiority was defined as the likelihood that tirofiban would preserve at least 50% of the ability of abciximab to reduce the primary end-point at 30 days, based on abciximab's demonstrated ability to reduce such events by 43% (relative risk, 0.573; 95% confidence interval [CI], 0.507-0.648; P < 0.001). To determine the probability of non-inferiority given the patients already enrolled, a Bayesian approach was used.

RESULTS

The primary composite end-point occurred in 8.8% of patients randomized to abciximab versus 6.9% receiving high-bolus-dose tirofiban (odds ratio, 0.77; 95% CI, 0.37-1.64). The estimated conditional power for the test that tirofiban would be non-inferior to abciximab if all patients been enrolled is 93.7%. Using the estimated predictive power method, the likelihood was 84.8%.

CONCLUSIONS

TENACITY was well powered to identify non-inferiority with tirofiban versus abciximab, and the patients enrolled strengthened the probability that this would have been the outcome had the trial been completed. When a clinical trial is terminated solely for financial reasons, it is incumbent upon the sponsor to provide proper patient follow-up and publication of the findings.

Loss of short-term symptomatic benefit in patients with an occluded infarct artery is unrelated to non-protocol revascularization: results from the Occluded Artery Trial (OAT)

BACKGROUND

the OAT found that routine late (3-28 days post-myocardial infarction) percutaneous coronary intervention (PCI) of an occluded infarct-related artery did not reduce death, reinfarction, or heart failure relative to medical treatment (MED). Angina rates were lower in PCI early, but the advantage over MED was lost by 3 years.

METHODS

angina and revascularization status were collected at 4 months, then annually. We assessed whether non-protocol revascularization procedures in MED accounted for loss of the early symptomatic advantage of PCI.

RESULTS

seven per 100 more PCI patients were angina-free at 4 months (P < .001) and 5 per 100 at 12 months (P = .005) with the difference narrowing to 1 per 100 at 3 years (P = .34). Non-protocol revascularization was more frequent in MED (5-year rate 22% vs 19% PCI, P = .05). Indications for revascularization included acute coronary syndromes (39% PCI vs 38% MED), stable angina/inducible ischemia (39% in each group), and physician preference (17% PCI vs 15% MED). Revascularization rates among patients with angina at any time during follow-up (35% of cohort) did not differ by treatment group (5-year rates 26% PCI vs 28% MED). Most symptomatic patients were treated without revascularization during follow-up (77%).

CONCLUSIONS

in a large randomized clinical trial of stable post-myocardial infarction patients, the modest benefit on angina from PCI of an occluded infarct-related artery was lost by 3 years. Revascularization was slightly more common in MED during follow-up but was not driven by acute ischemia, and almost 1 in 5 procedures were attributed to physician preference alone.

Upfront thrombus aspiration in primary coronary intervention for patients with ST-segment elevation acute myocardial infarction: report of the VAMPIRE (VAcuuM asPIration thrombus REmoval) trial

OBJECTIVES

This study evaluated safety and efficacy of upfront thrombus aspiration during primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Distal embolization during primary PCI results in reduced myocardial perfusion and poor clinical outcomes.

METHODS

The VAMPIRE (VAcuuM asPIration thrombus REmoval) study was a prospective, randomized, controlled multicenter trial conducted in 23 institutions. Patients (N = 355) presenting within 24 h of STEMI symptoms onset were randomized to primary PCI with (n = 180) or without (n = 175) upfront thrombus aspiration using Nipro's TransVascular Aspiration Catheter (Osaka, Japan).

RESULTS

The TransVascular Aspiration Catheter reached the lesion in 100% of cases. It successfully crossed the target obstruction in 86% without any delay in procedure time or time to reperfusion; whereas macroscopic thrombi were removed in 75% of the cases. Procedure success was similar between groups (98.9% vs. 98.3%). There was a trend toward lower incidence of slow or no reflow (primary end point-defined as a Thrombolysis In Myocardial Infarction flow grade <3) in patients treated with aspiration versus conventional primary PCI (12.4% vs. 19.4%, p = 0.07). Rate of myocardial blush grade 3 was higher in the aspiration group (46.0% vs. 20.5%, p < 0.001). Aspiration was most effective in patients presenting after 6 h of symptoms onset (slow flow rate: 8.1% vs. 37.6%, p = 0.01).

CONCLUSIONS

This study suggested the safety of primary PCI with upfront thrombectomy using a novel device in patients with STEMI. The study showed a trend toward improved myocardial perfusion and lower clinical events in patients treated with aspiration. Patients presenting late after STEMI appear to benefit the most from thrombectomy.

Lack of benefit from percutaneous intervention of persistently occluded infarct arteries after the acute phase of myocardial infarction is time independent: insights from Occluded Artery Trial

AIMS

The Occluded Artery Trial (OAT) (n = 2201) showed no benefit for routine percutaneous intervention (PCI) (n = 1101) over medical therapy (MED) (n = 1100) on the combined endpoint of death, myocardial infarction (MI), and class IV heart failure (congestive heart failure) in stable post-MI patients with late occluded infarct-related arteries (IRAs). We evaluated the potential for selective benefit with PCI over MED for patients enrolled early in OAT.

METHODS AND RESULTS

We explored outcomes with PCI over MED in patients randomized to the </=3 calendar days and </=7 calendar days post-MI time windows. Earlier, times to randomization in OAT were associated with higher rates of the combined endpoint (adjusted HR 1.04/day: 99% CI 1.01-1.06; P < 0.001). The 48-month event rates for </=3 days, </=7 days post-MI enrolled patients were similar for PCI vs. MED for the combined and individual endpoints. There was no interaction between time to randomization defined as a continuous (P = 0.55) or categorical variable with a cut-point of 3 days (P = 0.98) or 7 days (P = 0.64) post-MI and treatment effect.

CONCLUSION

Consistent with overall OAT findings, patients enrolled in the </=3 day and </=7 day post-MI time windows derived no benefit with PCI over MED with no interaction between time to randomization and treatment effect. Our findings do not support routine PCI of the occluded IRA in trial-eligible patients even in the earliest 24-72 h time window.

Coronary intervention for persistent occlusion after myocardial infarction

BACKGROUND

It is unclear whether stable, high-risk patients with persistent total occlusion of the infarct-related coronary artery identified after the currently accepted period for myocardial salvage has passed should undergo percutaneous coronary intervention (PCI) in addition to receiving optimal medical therapy to reduce the risk of subsequent events.

METHODS

We conducted a randomized study involving 2166 stable patients who had total occlusion of the infarct-related artery 3 to 28 days after myocardial infarction and who met a high-risk criterion (an ejection fraction of <50% or proximal occlusion). Of these patients, 1082 were assigned to routine PCI and stenting with optimal medical therapy, and 1084 were assigned to optimal medical therapy alone. The primary end point was a composite of death, myocardial reinfarction, or New York Heart Association (NYHA) class IV heart failure.

RESULTS

The 4-year cumulative primary event rate was 17.2% in the PCI group and 15.6% in the medical therapy group (hazard ratio for death, reinfarction, or heart failure in the PCI group as compared with the medical therapy group, 1.16; 95% confidence interval [CI], 0.92 to 1.45; P=0.20). Rates of myocardial reinfarction (fatal and nonfatal) were 7.0% and 5.3% in the two groups, respectively (hazard ratio, 1.36; 95% CI, 0.92 to 2.00; P=0.13). Rates of nonfatal reinfarction were 6.9% and 5.0%, respectively (hazard ratio, 1.44; 95% CI, 0.96 to 2.16; P=0.08); only six reinfarctions (0.6%) were related to assigned PCI procedures. Rates of NYHA class IV heart failure (4.4% vs. 4.5%) and death (9.1% vs. 9.4%) were similar. There was no interaction between treatment effect and any subgroup variable (age, sex, race or ethnic group, infarct-related artery, ejection fraction, diabetes, Killip class, and the time from myocardial infarction to randomization).

CONCLUSIONS

PCI did not reduce the occurrence of death, reinfarction, or heart failure, and there was a trend toward excess reinfarction during 4 years of follow-up in stable patients with occlusion of the infarct-related artery 3 to 28 days after myocardial infarction. (ClinicalTrials.gov number, NCT00004562 [ClinicalTrials.gov].).

Evolving Role of Low-Molecular-Weight Heparins in ST-Elevation Myocardial Infarction

OBJECTIVE:

To review the available literature on the efficacy and safety of low-molecular-weight heparin (LMWH) in the treatment of ST-elevation myocardial infarction (STEMI) in patients treated with fibrinolytic therapy or conservative medical management.

DATA SOURCES:

A MEDLINE search (1966–March 2004) using the key words myocardial infarction, STEMI, LMWH, enoxaparin, and dalteparin identified pertinent articles. The references of these articles were reviewed for additional pertinent references.

STUDY SELECTION AND DATA EXTRACTION:

All human trials of LMWH in STEMI were evaluated. All pertinent studies were included in the review.

DATA SYNTHESIS:

LMWH did not show a benefit in STEMI without fibrinolytic therapy. Enoxaparin is similar to intravenous unfractionated heparin (UFH) in combination with nonspecific fibrinolytic therapy with regard to invasive reperfusion markers and 30-day clinical outcomes. Enoxaparin decreases composite endpoints in combination with fibrin-specific fibrinolytic therapy compared with UFH, primarily through a reduction in the incidence of reinfarction at 30 days. Bleeding rates with LMWH in combination with fibrinolytic agents are not greater than those with UFH.

CONCLUSIONS:

Enoxaparin is a reasonable alternative to UFH in patients with STEMI treated with fibrin-specific fibrinolytic therapy. LMWH in patients managed with nonspecific fibrinolytic therapy or conservative medical treatment does not provide an advantage over standard management. Large clinical trials are ongoing which will provide more definitive recommendations.