Correlation of Non-Invasive Transthoracic Doppler Echocardiography with Invasive Doppler Wire-Derived Coronary Flow Reserve and Their Impact on Infarct Size in Patients with ST-Segment Elevation Myocardial Infarction Treated with Primary Percutaneous Coronary Intervention.

Background: Coronary microvascular dysfunction is associated with adverse prognosis after ST-segment elevation myocardial infarction (STEMI). We aimed to compare the invasive, Doppler wire-based coronary flow reserve (CFR) with the non-invasive transthoracic Doppler echocardiography (TTDE)-derived CFR, and their ability to predict infarct size. Methods: We included 36 patients with invasive Doppler wire assessment on days 3-7 after STEMI treated with primary percutaneous coronary intervention (PCI), of which TTDE-derived CFR was measured in 47 vessels (29 patients) within 6 h of the invasive Doppler. Infarct size was assessed by cardiac magnetic resonance at a median of 8 months. Results: The correlation between invasive and non-invasive CFR was modest in the overall cohort (rho 0.400, p = 0.005). It improved when only measurements in the LAD artery were considered (rho 0.554, p = 0.002), with no significant correlation in the RCA artery (rho -0.190, p = 0.435). Both invasive (AUC 0.888) and non-invasive (AUC 0.868) CFR, measured in the recanalized culprit artery, showed a good ability to predict infarct sizes ≥18% of the left ventricular mass, with the optimal cut off values of 1.85 and 1.80, respectively. Conclusions: In patients with STEMI, TTDE- and Doppler wire-derived CFR exhibit significant correlation, when measured in the LAD artery, and both have a similarly strong association with the final infarct size.

Coronary Microcirculation: The Next Frontier in the Management of STEMI.

Although the widespread adoption of timely invasive reperfusion strategies over the last two decades has significantly improved the prognosis of patients with ST-segment elevation myocardial infarction (STEMI), up to half of patients after angiographically successful primary percutaneous coronary intervention (PCI) still have signs of inadequate reperfusion at the level of coronary microcirculation. This phenomenon, termed coronary microvascular dysfunction (CMD), has been associated with impaired prognosis. The aim of the present review is to describe the collected evidence on the occurrence of CMD following primary PCI, means of assessment and its association with the infarct size and clinical outcomes. Therefore, the practical role of invasive assessment of CMD in the catheterization laboratory, at the end of primary PCI, is emphasized, with an overview of available technologies including thermodilution- and Doppler-based methods, as well as recently developing functional coronary angiography. In this regard, we review the conceptual background and the prognostic value of coronary flow reserve (CFR), index of microcirculatory resistance (IMR), hyperemic microvascular resistance (HMR), pressure at zero flow (PzF) and angiography-derived IMR. Finally, the so-far investigated therapeutic strategies targeting coronary microcirculation after STEMI are revisited.

Prognostic impact of non-culprit chronic total occlusion over time in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention.

AIMS: Previous studies indicated that a chronic total occlusion (CTO) in a non-infarct-related artery is linked to higher mortality mainly in the acute setting in patients with ST-elevation myocardial infarction (STEMI). Our aim was to assess the temporal distribution of mortality risk associated with non-culprit CTO over years after STEMI. METHODS AND RESULTS: The study included 8679 STEMI patients treated with primary percutaneous coronary intervention (PCI). Kaplan-Meier cumulative mortality curves for non-culprit CTO vs. no CTO were compared with log-rank test, with landmarks set at 30 days and 1 year. Adjusted Cox regression models were constructed to assess the impact of non-culprit CTO on mortality over different time intervals. Tests for interaction were pre-specified between non-culprit CTO and acute heart failure and left ventricular ejection fraction. The primary outcome variable was all-cause mortality, and the median follow-up was 5 years. Non-culprit CTO was present in 11.6% of patients (n = 1010). Presence of a CTO was associated with increased early [30-day adjusted hazard ratio (HR) 1.91, 95% confidence interval (CI) 1.54-2.36; P < 0.001] and late mortality (5-year adjusted HR 1.66, 95% CI 1.42-1.95; P < 0.001). Landmark analyses revealed an annual two-fold increase in mortality in patients with vs. without a CTO after the first year of follow-up. The observed pattern of mortality increase over time was independent of acute or chronic LV impairment. CONCLUSIONS: Non-culprit CTO is independently associated with mortality over 5 years after primary PCI for STEMI, with a constant annual two-fold increase in the risk of death beyond the first year of follow-up.

Improved Propensity-Score Matched Long-Term Clinical Outcomes in Patients with Successful Percutaneous Coronary Interventions of Coronary Chronic Total Occlusion.

The objective of the study was to evaluate major adverse cardiovascular events (MACE) after successful versus failed percutaneous coronary intervention for chronic total occlusion (PCI-CTO).Limited data are available on long-term clinical follow-up in the treatment of chronic total occlusion (CTO).Between January 2009 and December 2010 PCI-CTO was attempted in 283 consecutive patients with 289 CTO lesions. Procedural success was 62.3% and clinical follow-up covered 83% (235/283) of the study population with a median follow-up of 66 months (range, 59-74).The total incidence of MACE was 57/235 (24.3%), and was significantly higher in the procedural failure group than in the procedural success group (33/87 (37.9%) versus 24/148 (16.2%), P < 0.001). All-cause mortality was significantly lower in patients with successful PCI-CTO compared to failed PCI-CTO (10.8% versus 20.7%, P < 0.05). Also, the rate of cardiovascular death in the procedural failure group (14.9%) was slightly higher than that in the procedural success group (7.4%, P = 0.066). The rate of TVR was statistically higher in the procedural failure group (P < 0.009). Propensity score-adjusted Cox regression showed that procedural success remained a significant predictor of MACE (adjusted HR 0.402; 95% CI 0.196-0.824; P = 0.013).Our study emphasizes the importance of CTO recanalization in improving long-term outcome including all-cause mortality with a borderline effect on cardiovascular mortality.

Prognostic Value of Transthoracic Doppler Echocardiography Coronary Flow Velocity Reserve in Patients with Nonculprit Stenosis of Intermediate Severity Early after Primary Percutaneous Coronary Intervention.

BACKGROUND: Treatment of nonculprit coronary stenosis during primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction may be beneficial, but the mode and timing of the intervention are still controversial. The aim of this study was to examine the significance and prognostic value of preserved coronary flow velocity reserve (CFVR) in patients with nonculprit intermediate stenosis early after primary percutaneous coronary intervention. METHODS: Two hundred thirty patients with remaining intermediate (50%-70%) stenosis of non-infarct-related arteries, in whom CFVR was performed within 7 days after primary percutaneous coronary intervention, were prospectively enrolled. Twenty patients with reduced CFVR and positive results on stress echocardiography or impaired fractional flow reserve underwent revascularization and were not included in further analysis. The final study population of 210 patients (mean age, 58 ± 10 years; 162 men) was divided into two groups on the basis of CFVR: group 1, CFVR > 2 (n = 174), and group 2, CFVR ≤ 2 (n = 36). Cardiac death, nonfatal myocardial infarction, and revascularization of the evaluated vessel were considered adverse events. RESULTS: Mean follow-up duration was 47 ± 16 months. Mean CFVR for the whole group was 2.36 ± 0.40. There were six adverse events (3.4%) related to the nonculprit coronary artery in group 1, including one cardiac death, one ST-segment elevation myocardial infarction, and four revascularizations. In group 2, there were 30 adverse events (83.3%, P < .001 vs group 1), including two cardiac deaths, two ST-segment elevation myocardial infarctions, and 26 revascularizations. CONCLUSIONS: In patients with CFVR > 2 of the intermediate nonculprit coronary lesion, deferral of revascularization is safe and associated with excellent long-term clinical outcomes.

COOL AMI EU pilot trial: a multicentre, prospective, randomised controlled trial to assess cooling as an adjunctive therapy to percutaneous intervention in patients with acute myocardial infarction.

AIMS: We aimed to investigate the rapid induction of therapeutic hypothermia using the ZOLL Proteus Intravascular Temperature Management System in patients with anterior ST-elevation myocardial infarction (STEMI) without cardiac arrest. METHODS AND RESULTS: A total of 50 patients were randomised; 22 patients (88%; 95% confidence interval [CI]: 69-97%) in the hypothermia group and 23 patients (92%; 95% CI: 74-99) in the control group completed cardiac magnetic resonance imaging at four to six days and 30-day follow-up. Intravascular temperature at coronary guidewire crossing after 20.5 minutes of endovascular cooling decreased to 33.6°C (range 31.9-35.5°C). There was a 17-minute (95% CI: 4.6-29.8 min) cooling-related delay to reperfusion. In "per protocol" analysis, median infarct size/left ventricular mass was 16.7% in the hypothermia group versus 23.8% in the control group (absolute reduction 7.1%, relative reduction 30%; p=0.31) and median left ventricular ejection fraction (LVEF) was 42% in the hypothermia group and 40% in the control group (absolute reduction 2.4%, relative reduction 6%; p=0.36). Except for self-terminating paroxysmal atrial fibrillation (32% versus 8%; p=0.074), there was no excess of adverse events in the hypothermia group. CONCLUSIONS: We rapidly and safely cooled patients with anterior STEMI to 33.6°C at the time of coronary guidewire crossing. This is ≥1.1°C lower than in previous cooling studies. Except for self-terminating atrial fibrillation, there was no excess of adverse events and no clinically important cooling-related delay to reperfusion. A statistically non-significant numerical 7.1% absolute and 30% relative reduction in infarct size warrants a pivotal trial powered for efficacy.

Contemporary techniques for coronary CTO revascularization.

Despite permanent improvement in success rate and technical developments, chronic total occlusion (CTO) remains undertreated by percutaneous coronary intervention (PCI). Dedicated CTO operators from Japan, Europe and USA perform these procedures with success rate beyond 90%, but there is still huge gap between this group of specialists and broader population of PCI operators. Recently proposed CTO scores can be used for patients' selection according to the CTO operators' experience. Patients with low CTO Score values may be suitable for less experienced operators at the beginning of the CTO PCI learning curve, while more complex CTOs (higher CTO Score values) should be differed to CTO experts. As most of CTO scores better predict antegrade procedural success, at the hands of expert CTO operators, lower or intermediate CTO Score values suggest cases which could be started by anterograde techniques. In this paper we review: 1) an impact of CTO on completeness of revascularization; 2) appropriate CTO equipment setting; 3) procedure planning aspects, including the use of computed tomography angiography and CTO scores; 4) current CTO techniques classifying them into A) antegrade, B) retrograde and C) hybrid approach. Further advancements in CTO PCI should not only provide higher rate of complete revascularization, with improved clinical outcome, but also simplify procedure and make it suitable for broader spectrum of interventionalists.

Prognostic implications of bleeding measured by Bleeding Academic Research Consortium (BARC) categorisation in patients undergoing primary percutaneous coronary intervention.

OBJECTIVE: To investigate the relationship between inhospital bleeding as defined by Bleeding Academic Research Consortium (BARC) consensus classification and short-term and long-term mortality in unselected patients admitted for primary percutaneous coronary intervention (PCI). METHODS: We analysed data of all consecutive patients with ST segment elevation myocardial infarction (STEMI) admitted for primary PCI, enrolled in a prospective registry of a high volume centre. The BARC-defined bleeding events were reconstructed from the detailed, prospectively collected clinical data. The primary outcome was mortality at 1 year. RESULTS: Of the 1808 patients with STEMI admitted for primary PCI, 115 (6.4%) experienced a BARC type ≥2 bleeding. As the BARC bleeding severity worsened, there was a gradient of increasing rates of 1-year death. The 1-year mortality rate increased from 11.5% with BARC 0+1 type to 43.5% with BARC type 3b bleeding. After multivariable adjustment for demographic and clinical characteristics of patients, the independent predictors of 1-year death were BARC type 3a (HR 1.99; 95% CI 1.16 to 3.40, p=0.012) and BARC type 3b bleeding (HR 3.22; 95% CI 1.67 to 6.20, p<0.0001). CONCLUSIONS: The present study demonstrated that bleeding events defined according to the BARC classification hierarchically correlate with 1-year mortality after admission for primary PCI. The strongest predictor of 1-year mortality is the BARC type 3b bleeding.