Patency of infarct related artery after pharmacological reperfusion during transfer to primary percutaneous coronary intervention influences left ventricular function and one-year clinical outcome

Heart failure after myocardial infarction in the era of primary percutaneous coronary intervention: Mechanisms, incidence and identification of patients at risk

Myocardial infarction (MI) remains the most common cause of heart failure (HF) worldwide. For almost 50 years HF has been recognised as a determinant of adverse prognosis after MI, but efforts to promote myocardial repair have failed to translate into clinical therapies. Primary percutaneous coronary intervention (PPCI) has driven improved early survival after MI, but its impact on the incidence of downstream HF is debated. The effects of PPCI are confounded by the changing epidemiology of MI and HF, with an ageing patient demographic, an increasing proportion of non-ST-elevation myocardial infarction, and the recognition of HF with preserved ejection fraction. Herein we review the mechanisms of HF after MI and discuss contemporary data on its incidence and outcomes. We review current and emerging strategies for early detection of patients at risk of HF after MI, with a view to identification of patient cohorts for novel therapeutic agents.

Preprocedural TIMI flow and infarct size in STEMI undergoing primary angioplasty

Despite optimal epicardial recanalization, primary angioplasty for STEMI is still associated with suboptimal reperfusion in a relatively large proportion of patients. The aim the current study was to evaluate the impact of preprocedural TIMI flow on myocardial scintigraphic infarct size among STEMI undergoing primary angioplasty. Our population is represented by 793 STEMI patients undergoing primary PCI. Infarct size was evaluated at 30 days by technetium-99m-sestamibi. Poor preprocedural TIMI flow (TIMI 0-1) was observed in 645 patients (81.3%). Poor preprocedural TIMI flow was associated with more hypercholesterolemia (p = 0.012), and a trend in lower prevalence of diabetes (p = 0.081). Preprocedural TIMI flow significantly affected scintigraphic and enzymatic infarct size. Similar findings were observed in the analysis restricted to patients with postprocedural TIMI 3 flow. The impact of preprocedural TIMI flow on scintigraphic infarct size was confirmed when the analysis was performed according to the percentage of patients above the median (p < 0.001) and after adjustment for baseline confounding factors (Hypercholesterolemia and diabetes) [adjusted OR (95% CI) for pre preprocedural TIMI 3 flow = 0.59 (0.46-0.75), p < 0.001]. This study shows that among patients with STEMI undergoing primary angioplasty, poor preprocedural TIMI flow is independently associated with larger infarct size.

The MI SYNTAX score for risk stratification in patients undergoing primary percutaneous coronary intervention for treatment of acute myocardial infarction: a substudy of the COMFORTABLE AMI trial

BACKGROUND

To investigate the performance of the MI Sxscore in a multicentre randomised trial of patients undergoing primary percutaneous coronary intervention (PPCI).

METHODS AND RESULTS

The MI Sxscore was prospectively determined among 1132 STEMI patients enrolled into the COMFORTABLE AMI trial, which randomised patients to treatment with bare-metal (BMS) or biolimus-eluting (BES) stents. Patient- (death, myocardial infarction, any revascularisation) and device-oriented (cardiac death, target-vessel MI, target lesion revascularisation) major adverse cardiac events (MACEs) were compared across MI Sxscore tertiles and according to stent type. The median MI SXscore was 14 (IQR: 9-21). Patients were divided into tertiles of Sxscorelow (≤10), Sxscoreintermediate (11-18) and Sxscorehigh (≥19). At 1 year, patient-oriented MACE occurred in 15% of the Sxscorehigh, 9% of the Sxscoreintermediate and 5% of the Sxscorelow tertiles (p<0.001), whereas device-oriented MACE occurred in 8% of the Sxscorehigh, 6% of the Sxscoreintermediate and 4% of the Sxscorelow tertiles (p=0.03). Addition of the MI Sxscore to the TIMI risk score improved prediction of patient- (c-statistic value increase from 0.63 to 0.69) and device-oriented MACEs (c-statistic value increase from 0.65 to 0.70). Differences in the risk for device-oriented MACE between BMS and BES were evident among Sxscorehigh (13% vs. 4% HR 0.33 (0.15-0.74), p=0.007 rather than those in Sxscorelow: 4% vs. 3% HR 0.68 (0.24-1.97), p=0.48) tertiles.

CONCLUSIONS

The MI Sxscore allows risk stratification of patient- and device-oriented MACEs among patients undergoing PPCI. The addition of the MI Sxscore to the TIMI risk score is of incremental prognostic value among patients undergoing PPCI for treatment of STEMI.

Usefulness of the SYNTAX score to predict "no reflow" in patients treated with primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

The no-reflow phenomenon has been shown to have a significant effect on clinical outcomes in patients with acute ST-segment elevation myocardial infarction. Angiographic features incorporated in the SYNTAX Score (SXScore) obtained on diagnostic angiography during primary percutaneous coronary intervention (PPCI) may be associated with the occurrence of myocardial no-reflow. The aim of this study was to assess the ability of the SXScore to predict no-reflow during PPCI. The SXScore was applied to 669 consecutive patients presenting with acute ST-segment elevation myocardial infarction from November 2006 to February 2008. Angiographic analysis of the PPCI procedure was used to determine no-reflow. The median SXScore was 16 (range 9.5 to 23). No-reflow occurred in 77 patients (12%). On univariate logistic regression analysis, the SXScore showed a strong association (for each 10-unit increase in SXScore, odds ratio 1.42, 95% confidence interval 1.16 to 1.76, p <0.001). On multivariate logistic regression in a model including clinical variables, SXScore was an independent predictor of no-reflow (odds ratio 1.29, 95% confidence interval 1.02 to 1.63, p <0.001). Classification and regression tree analysis identified SXScore >21 as the best cutoff, with patients having double the risk for no-reflow compared to those with SXScore ≤21 (events 9% vs 18%, p = 0.006). In conclusion, the SXScore obtained in the diagnostic phase of PPCI for acute ST-segment elevation myocardial infarction can identify patients at risk for developing no-reflow.

Persistent coronary no flow after wire insertion is an early and readily available mortality risk factor despite successful mechanical intervention in acute myocardial infarction: a pooled analysis from the STRATEGY (Single High-Dose Bolus Tirofiban and Sirolimus-Eluting Stent Versus Abciximab and Bare-Metal Stent in Acute Myocardial Infarction) and MULTISTRATEGY (Multicenter Evaluation of Single High-Dose Bolus Tirofiban Versus Abciximab With Sirolimus-Eluting Stent or Bare-Metal Stent in Acute Myocardial Infarction Study) trials

OBJECTIVES

These studies sought to investigate the impact on mortality of coronary flow after passage of the wire through the culprit vessel in patients with ST-segment elevation myocardial infarction (STEMI) undergoing mechanical reperfusion.

BACKGROUND

Reduced spontaneous coronary flow before percutaneous coronary intervention influences mortality in patients with STEMI. Response to vessel wiring in patients with an occluded coronary artery before intervention might further discriminate outcomes irrespective of pre- and post-intervention coronary flow.

METHODS

Data from the STRATEGY (Single High-Dose Bolus Tirofiban and Sirolimus-Eluting Stent Versus Abciximab and Bare-Metal Stent in Acute Myocardial Infarction) and MULTISTRATEGY (Multicenter Evaluation of Single High-Dose Bolus Tirofiban Versus Abciximab With Sirolimus-Eluting Stent or Bare-Metal Stent in Acute Myocardial Infarction Study) trials were pooled: of 919 index procedures, 902 films (98%) were technically adequate for core laboratory TIMI (Thrombolysis In Myocardial Infarction) flow determination.

RESULTS

TIMI flow grade 0 was present before percutaneous coronary intervention in 59% of infarct vessels, TIMI flow grade 1 to 2 was found in 21%, whereas the remainder of infarct arteries presented with TIMI flow grade 3. In 49% of patients who showed persistent TIMI flow grade 0 after wire insertion (AWI), mortality was higher at 30 days (5.3%) and 1 year (9.4%) compared with patients in whom TIMI flow grade before percutaneous coronary intervention was either >0 (0.8%; p < 0.003 and 3.6%, p < 0.008) or improved from 0 AWI (1.5%, p < 0.04 and 3.6%, p < 0.02). After correcting for multiple imbalances, including baseline and final flow, persistent TIMI flow grade 0 AWI remained associated at 30 days to 2-fold (risk ratio [RR]: 2.1, 95% confidence interval [CI]: 1.08 to 5.00; p = 0.038) and at 1 year to almost 3-fold increases of mortality (RR: 2.7, 95% CI: 1.3 to 5.6; p = 0.008).

CONCLUSIONS

STEMI patients displaying persistent no-flow AWI have a lower survival rate despite an apparently successful mechanical intervention. As an early marker for high residual mortality risk, persistent no-flow AWI may qualify STEMI patients for dedicated pharmacomechanical treatment strategies.

Angiographic perfusion score assessed in patients with acute myocardial infarction is correlated with cardiac magnetic resonance infarct size and N-terminal pro-brain natriuretic peptide in 6-month follow-up

Angiographic Perfusion Score (APS) proposed as a simple, angiographic score linking epicardial and myocardial perfusion parameters before and after percutaneous coronary intervention (PCI) is a predictor of short-term outcome in patients with ST-segment elevation myocardial infarction (STEMI) treated with PCI. Aim of the study was to analyze the correlation between APS and both infarct size and left ventricular function in long-term follow-up. In a cohort of 68 patients with STEMI treated with PCI APS was calculated for infarct-related artery based on angiographic parameters and was defined as the sum of the Thrombolysis in Myocardial Infarction (TIMI) flow grade (0-3 points) and the TIMI myocardial perfusion grade (0-3 points) before and after PCI (range of points from 0 to 12). Full perfusion was defined as APS ≥ 10. Cardiac magnetic resonance (CMR) parameters and N-terminal pro-brain natriuretic peptide (NT pro-BNP) were assessed at 6 months.

RESULTS

Median APS was 7.5 points. APS ≥ 10 was present in 42% of patients. The significant correlation was found between APS and: CMR infarct size (r = - 0.48; P = 0.0001), CMR left ventricular (LV) ejection fraction (r = 0.5; P = 0.002), LV end-diastolic volume index (r = - 0.37; P = 0.004), LV end-systolic volume index (r = -0.41; P = 0.001), NT pro-BNP (r = - 0.5; P = 0.02). Patients with APS ≥ 10 had significantly lower infarct size, LV volumes, higher EF and lower NT pro-BNP. APS assessed in patients with STEMI treated with PCI is a good predictor of infarct size and left ventricular function in 6-month follow-up.

Early treatment with abciximab in patients with ST elevation myocardial infarction results in a high rate of normal or near normal blood flow in the infarct related artery

There is debate whether early treatment with GpIIb/IIIa inhibitors is of clinical benefit in primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). This study explored the effects of early given abciximab on coronary blood flow and major adverse cardiac events (MACE) in patients with STEMI treated with primary PCI and adjunctive abciximab. We studied all consecutive patients from our catchment area with STEMI undergoing acute angiography with the intention of primary PCI during 2005. Abciximab was given as early pre-treatment before, (n = 133) or at the cath. lab. after a diagnostic angiography (n = 109). Pre-procedural TIMI 2-3 flow was observed in 45.9 % of patients in the early group versus 20.2 % in the cath. lab. group, P = 0.0001. Mortality rates were 3.8 % versus 3.7% inhospital and 8.3 % versus 7.3% at one year in the early respectively the cath. lab. group, both P = NS. The MACE rate (death, non fatal myocardial infarction, unplanned revascularization) at one year was 19.5 % (early group) and 26.6 % (cath. lab. group), P = 0.19.

CONCLUSION

In this single centre registry study of unselected patients with STEMI early given abciximab was associated with a significantly higher rate of TIMI 2-3 flow compared to abciximab given after the acute angiography.