Non-invasive myocardial work in aortic stenosis: validation and improvement in left ventricular pressure estimation.

AIMS: The non-invasive myocardial work index (MWI) has been validated in patients without aortic stenosis (AS). A thorough assessment of methodological limitations is warranted before this index can be applied to patients with AS. METHODS AND RESULTS: We simultaneously measured left ventricular pressure (LVP) by using a micromanometer-tipped catheter and obtained echocardiograms in 20 patients with severe AS. We estimated LVP curves and calculated pressure-strain loops using three different models: (i) the model validated in patients without AS; (ii) the same model, but with pressure at the aortic valve opening (AVO) adjusted to diastolic cuff pressure; and (iii) a new model based on the invasive measurements from patients with AS. Valvular events were determined by echocardiography. Peak LVP was estimated as the sum of the mean aortic transvalvular gradient and systolic cuff pressure. In same-beat comparisons between invasive and estimated LVP curves, Model 1 significantly overestimated early systolic pressure by 61 ± 5 mmHg at AVO compared with Models 2 and 3. However, the average correlation coefficients between estimated and invasive LVP traces were excellent for all models, and the overestimation had limited influence on MWI, with excellent correlation (r = 0.98, P < 0.001) and good agreement between the MWI calculated with estimated (all models) and invasive LVP. CONCLUSION: This study confirms the validity of the non-invasive MWI in patients with AS. The accuracy of estimated LVP curves improved when matching AVO to the diastolic pressure in the original model, mirroring that of the AS-specific model. This may sequentially enhance the accuracy of regional MWI assessment.

Long-Term Outcomes of Invasive vs Conservative Strategies for Older Patients With Non-ST-Segment Elevation Acute Coronary Syndromes.

BACKGROUND: Non-ST-segment elevation acute coronary syndrome (NSTE-ACS) is a frequent cause of hospital admission in older people, but clinical trials targeting this population are scarce. OBJECTIVES: The After Eighty Study assessed the effect of an invasive vs a conservative treatment strategy in a very old population with NSTE-ACS. METHODS: Between 2010 and 2014, the investigators randomized 457 patients with NSTE-ACS aged ≥80 years (mean age 85 years) to an invasive strategy involving early coronary angiography with immediate evaluation for revascularization and optimal medical therapy or to a conservative strategy (ie, optimal medical therapy). The primary endpoint was a composite of myocardial infarction, need for urgent revascularization, stroke, and death. The long-term outcomes are presented. RESULTS: After a median follow up of 5.3 years, the invasive strategy was superior to the conservative strategy in the reduction of the primary endpoint (incidence rate ratio: 0.76; 95% CI: 0.63-0.93; P = 0.0057). The invasive strategy demonstrated a significant gain in event-free survival of 276 days (95% CI: 151-400 days; P = 0.0001) at 5 years and 337 days (95% CI: 123-550 days; P = 0.0001) at 10 years. These results were consistent across subgroups of patients with respect to major cardiovascular prognostic factors. CONCLUSIONS: In patients aged ≥80 years with NSTE-ACS, the invasive strategy was superior to the conservative strategy in the reduction of composite events and demonstrated a significant gain in event-free survival. (The After Eighty Study: a randomized controlled trial; NCT01255540).

OCT or Angiography Guidance for PCI in Complex Bifurcation Lesions.

BACKGROUND: Imaging-guided percutaneous coronary intervention (PCI) is associated with better clinical outcomes than angiography-guided PCI. Whether routine optical coherence tomography (OCT) guidance in PCI of lesions involving coronary-artery branch points (bifurcations) improves clinical outcomes as compared with angiographic guidance is uncertain. METHODS: We conducted a multicenter, randomized, open-label trial at 38 centers in Europe. Patients with a clinical indication for PCI and a complex bifurcation lesion identified by means of coronary angiography were randomly assigned in a 1:1 ratio to OCT-guided PCI or angiography-guided PCI. The primary end point was a composite of major adverse cardiac events (MACE), defined as death from a cardiac cause, target-lesion myocardial infarction, or ischemia-driven target-lesion revascularization at a median follow-up of 2 years. RESULTS: We assigned 1201 patients to OCT-guided PCI (600 patients) or angiography-guided PCI (601 patients). A total of 111 patients (18.5%) in the OCT-guided PCI group and 116 (19.3%) in the angiography-guided PCI group had a bifurcation lesion involving the left main coronary artery. At 2 years, a primary end-point event had occurred in 59 patients (10.1%) in the OCT-guided PCI group and in 83 patients (14.1%) in the angiography-guided PCI group (hazard ratio, 0.70; 95% confidence interval, 0.50 to 0.98; P = 0.035). Procedure-related complications occurred in 41 patients (6.8%) in the OCT-guided PCI group and 34 patients (5.7%) in the angiography-guided PCI group. CONCLUSIONS: Among patients with complex coronary-artery bifurcation lesions, OCT-guided PCI was associated with a lower incidence of MACE at 2 years than angiography-guided PCI. (Funded by Abbott Vascular and others; OCTOBER ClinicalTrials.gov number, NCT03171311.).

An investigator-sponsored pragmatic randomized controlled trial of AntiCoagulation vs AcetylSalicylic Acid after Transcatheter Aortic Valve Implantation: Rationale and design of ACASA-TAVI.

BACKGROUND: The optimal antithrombotic therapy after transcatheter aortic valve implantation (TAVI) is unknown. Bioprosthetic valve dysfunction (BVD) is associated with adverse outcomes and may be prevented by anticoagulation therapy. A dedicated randomized trial comparing monotherapy NOAC to single antiplatelet therapy has not been performed previously. We hypothesize that therapy with any anti-factor Xa NOAC will reduce BVD compared to antiplatelet therapy, without compromising safety. METHODS: ACASA-TAVI is a multicenter, prospective, randomized, open-label, blinded endpoint, all-comers trial comparing a monotherapy anti-factor Xa NOAC strategy (intervention arm) with a single antiplatelet therapy strategy (control arm) after successful TAVI. Three-hundred and sixty patients without indication for oral anticoagulation will be randomized in a 1:1 ratio to either apixaban 5 mg twice per day, edoxaban 60 mg daily, or rivaroxaban 20 mg daily for 12 months followed by acetylsalicylic acid 75 mg daily indefinitely, or to acetylsalicylic acid 75 mg daily indefinitely. The 2 co-primary outcomes are (1) incidence of Hypo-Attenuated Leaflet Thickening (HALT) on 4-dimensional cardiac CT at 12 months, and (2) a Safety Composite of VARC-3 bleeding events, thromboembolic events (myocardial infarction and stroke), and death from any cause, at 12 months. RESULTS: The first 100 patients had a mean age of 74 ± 3.6 years, 33% were female, the average body-mass index was 27.9 ± 4.4 kg/m2, and 15% were smokers. A balloon-expanded valve was used in 82% and a self-expandable valve in 18%. CONCLUSIONS: The trial is planned, initiated, funded, and conducted without industry involvement. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT05035277.

Guideline-Recommended Time Less Than 90 Minutes From ECG to Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction Is Associated with Major Survival Benefits, Especially in Octogenarians: A Contemporary Report in 11 226 Patients from NORIC.

Background Using contemporary data from NORIC (Norwegian Registry of Invasive Cardiology) we investigated the predictive value of patient age and time from ECG diagnosis to sheath insertion (ECG-2-sheath) in primary percutaneous coronary intervention for ST-segment-elevation myocardial infarction (STEMI). Methods and Results Data from 11 226 patients collected from all centers offering 24/7/365 primary percutaneous coronary intervention service were explored. For patients aged <80 years the mortality rates were 5.6% and 7.6% at 30 days and 1 year, respectively. For octogenarians the corresponding rates were 15.0% and 24.2%. The Cox hazard ratio was 2.02 (1.93-2.11, P value <0.0001) per 10 years of patient age. Time from ECG-2-sheath was significantly associated with mortality with a 3.6% increase per 30 minutes of time. Using achievement of time goal <90 minutes in patients aged >80 years and mortality at 30 days, mortality was 10.5% and 17.7% for <90 or ≥90 minutes, respectively. The number needed to prevent 1 death was 39 in the whole population and 14 in the elderly. Restricted mean survival gains during median 938 days of follow-up in patients with ECG-2-sheath time <90 minutes were 24 and 76 days for patients aged <80 and ≥80 years, respectively. Conclusions Time from ECG-diagnosis to sheath insertion is strongly correlated with mortality. This applies especially to octogenarians who derive the most in terms of absolute mortality reduction. Registration URL: https://helsedata.no/en/forvaltere/norwegian-institute-of-public-health/norwegian-registry-of-invasive-cardiology/.

Thrombus formation in the noncoronary sinus of Valsalva following primary graft dysfunction.

We hereby present a case of thrombus formation in the noncoronary sinus of Valsalva following primary graft dysfunction. The case highlights that stagnant and nonpulsatile flow can form thrombi in the noncoronary sinus since this sinus does not have a natural distal runoff.

Patients aged 80 years or older with non-ST-elevation myocardial infarction or unstable angina pectoris randomised to an invasive versus conservative strategy: angiographic and procedural results from the After Eighty study.

OBJECTIVES: We aimed to report the angiographic and procedural results of the After Eighty study (ClinicalTrials.gov, NCT01255540), and to identify independent predictors of revascularisation. METHODS: Patients of ≥80 years old with non-ST-elevation myocardial infarction and unstable angina pectoris were randomised to an invasive or conservative strategy. Angiographic and procedural results were recorded. Univariate and multivariate analyses were performed to explore variables predicting revascularisation. RESULTS: Among 229 patients in the invasive group, 220 underwent immediate coronary angiography (90% performed via the radial artery). Of these patients, 48% had three-vessel disease or left main stenosis, 18% two-vessel disease, 16% one-vessel disease, 17% minor coronary vessel wall changes and two patients had normal coronary arteries. Six patients (3%) underwent coronary artery bypass graft. Percutaneous coronary intervention (PCI) was performed in 107 patients (49%), with 57% treated with bare metal stents, 37% drug-eluting stents and 6% balloon angioplasty. On average, 1.7 lesions were treated and 2 stents delivered per patient. Complications included 1 major PCI-related bleeding (successfully treated), 2 minor access site-related bleedings, 3 side branch occlusions during PCI and 11 periprocedural myocardial infarctions (considered end points). Sex, bundle branch block and smoking were independent predictors of revascularisation. CONCLUSIONS: PCI was performed in approximately half of the patients, similar to findings in younger populations. Procedural success was high, with few complications. TRIAL REGISTRATION NUMBER: NCT01255540.

Mechanical dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease.

Assessment of global longitudinal strain (GLS) is superior to ejection fraction (EF) in the evaluation of left ventricular (LV) function in patients with stable coronary artery disease (CAD). However, the role of mechanical dispersion (MD) in this context remains unresolved. We aimed to evaluate the potential role of MD as a marker of LV dysfunction and long-term prognosis in stable CAD. EF, GLS and MD were assessed in 160 patients with stable CAD, 1 year after successful coronary revascularization. Serum levels of high-sensitivity cardiac troponin I (hs-cTnI) and amino-terminal pro B-type natriuretic peptide (NT-proBNP) were quantified as surrogate markers of LV dysfunction. The primary endpoint was defined as all-cause mortality, the secondary endpoint was defined as the composite of all-cause mortality and hospitalization for acute myocardial infarction or heart failure during follow-up. Whereas no associations between EF and the biochemical markers of LV function were found, both GLS and MD correlated positively with increasing levels of hs-cTnI (R = 0.315, P < 0.001 and R = 0.442, P < 0.001, respectively) and NT-proBNP (R = 0.195, P = 0.016 and R = 0.390, P < 0.001, respectively). Median MD was 46 ms (interquartile range [IQR] 37-53) and was successfully quantified in 96% of the patients. During a median follow-up of 8.4 (IQR 8.2-8.8) years, 14 deaths and 29 secondary events occurred. MD was significantly increased in non-survivors, and provided incremental prognostic value when added to EF and GLS. NT-proBNP was superior to the echocardiographic markers in predicting adverse outcomes. MD may be a promising marker of LV dysfunction and adverse prognosis in stable CAD.

Six months versus 12 months dual antiplatelet therapy after drug-eluting stent implantation in ST-elevation myocardial infarction (DAPT-STEMI): randomised, multicentre, non-inferiority trial.

OBJECTIVE: To show that limiting dual antiplatelet therapy (DAPT) to six months in patients with event-free ST-elevation myocardial infarction (STEMI) results in a non-inferior clinical outcome versus DAPT for 12 months. DESIGN: Prospective, randomised, multicentre, non-inferiority trial. SETTING: Patients with STEMI treated with primary percutaneous coronary intervention (PCI) and second generation zotarolimus-eluting stent. PARTICIPANTS: Patients with STEMI aged 18 to 85 that underwent a primary PCI with the implantation of second generation drug-eluting stents were enrolled in the trial. Patients that were event-free at six months after primary PCI were randomised at this time point. INTERVENTIONS: Patients that were taking DAPT and were event-free at six months were randomised 1:1 to single antiplatelet therapy (SAPT) (ie, aspirin only) or to DAPT for an additional six months. All patients that were randomised were then followed for another 18 months (ie, 24 months after the primary PCI). MAIN OUTCOME MEASURES: The primary endpoint was a composite of all cause mortality, any myocardial infarction, any revascularisation, stroke, and thrombolysis in myocardial infarction major bleeding at 18 months after randomisation. RESULTS: A total of 1100 patients were enrolled in the trial between 19 December 2011 and 30 June 2015. 870 were randomised: 432 to SAPT versus 438 to DAPT. The primary endpoint occurred in 4.8% of patients receiving SAPT versus 6.6% of patients receiving DAPT (hazard ratio 0.73, 95% confidence interval 0.41 to 1.27, P=0.26). Non-inferiority was met (P=0.004 for non-inferiority), as the upper 95% confidence interval of 1.27 was smaller than the prespecified non-inferiority margin of 1.66. CONCLUSIONS: DAPT to six months was non-inferior to DAPT for 12 months in patients with event-free STEMI at six months after primary PCI with second generation drug-eluting stents. TRIAL REGISTRATION: Clinicaltrials.gov NCT01459627.

Rational and design of the European randomized Optical Coherence Tomography Optimized Bifurcation Event Reduction Trial (OCTOBER).

Background: Percutaneous coronary intervention in complex bifurcation lesions is prone to suboptimal implantation results and is associated with increased risk of subsequent clinical events. Angiographic ambiguity is high during bifurcation stenting, but it is unknown if procedural guidance by intravascular optical coherence tomography (OCT) improves clinical outcome. Methods and Design: OCTOBER is a randomized, investigator-initiated, multicenter trial aimed to show superiority of OCT-guided stent implantation compared to standard angiographic-guided implantation in bifurcation lesions. The primary outcome measure is a 2-year composite end point of cardiac death, target lesion myocardial infarction, and ischemia-driven target lesion revascularization. The calculated sample size is 1,200 patients in total, and allocation is 1:1. Eligible patients have stable or unstable angina pectoris or stabilized non­ST elevation myocardial infarction, and a coronary bifurcation lesion with significant main vessel stenosis and more than 50 % stenosis in a side branch with a reference diameter ≥2.5mm. Treatment is performed by the provisional side branch stenting technique or 2-stent techniques, and the systematic OCT guiding protocol is aimed to evaluate (1) plaque preparation, (2) lesion length, (3) segmental reference sizes, (4) lesion coverage, (5) stent expansion, (6) malapposition, (7) wire positions, and (8) ostial results. Implications: A positive outcome of the OCTOBER trial may establish OCT as a routine tool for optimization of complex percutaneous coronary intervention, whereas a negative result would indicate that OCT remains a tool for ad hoc evaluation in selected cases.

Troponinas de alta sensibilidad T vs I en Sindrome Coronario Agudo: Predicción de lesiones coronarias significativas y pronóstico a largo plazo / High-Sensitivity Troponin T vs I in Acute Coronary Syndrome: Prediction of Significant Coronary Lesions and Long-term Prognosis

Antecedentes: Los ensayos de troponinas cardíacas de alta sensibilidad (hs-cTn) tanto T e I son una herramienta crucial y bien establecida para el diagnóstico de infarto agudo de miocardio (IAM), ya que se ha demostrado ampliamente su superioridad respecto a las antiguas determinaciones de troponina. Sin embargo, eventuales diferencias entre ambos ensayos en la predicción de lesiones coronarias significativas y el pronóstico a largo plazo en pacientes con síndrome coronario agudo (SCA) no han sido aclarados completamente. Métodos: Se evaluaron las concentraciones séricas de hs-cTnT (Roche), hs-cTnI (Abbott) y porción amino-terminal del pro-péptido natriurético tipo B (NT-proBNP) (Roche) en 390 pacientes con SCA sin elevación del segmento ST, y se relacionaron con lesiones coronarias significativas detectadas por angiografía coronaria (definidas como estenosis >50% del diámetro luminal, con necesidad de revascularización) y con la precisión pronóstica de mortalidad cardiovascular, mortalidad por cualquier causa, así como también con el punto final compuesto por mortalidad cardiovascular y hospitalizaciones por IAM o insuficiencia cardiaca. Resultados: La media (+DE) del seguimiento fue de 2921+168 días. Las concentraciones absolutas de hs-cTnI fueron significativamente mayores que las concentraciones de hs-cTnT. La relación entre los biomarcadores analizados y lesiones coronarias significativas en angiografía coronaria, cuantificada por el área bajo la curva ROC (AUC), no reveló diferencias entre hs-cTnT [AUC, 0,81; IC del 95%, 0,77- 0,86] y hs-cTnI (AUC, 0,81; IC del 95%, 0,76-0,86; P=NS). Sin embargo, NT-proBNP fue superior a ambos ensayos de hs-cTn en relación con la precisión pronóstica tanto para mortalidad cardiovascular y por cualquier causa, como para el punto final compuesto durante el seguimiento, aún también en análisis multivariados. Conclusiones: Los determinaciones de hs-cTnT y hs-cTnI mostraron una capacidad similar para predecir lesiones coronarias significativas en pacientes con SCA sin elevación del segmento ST. NT-proBNP fue superior a ambos ensayos de uscTn, como marcador de pronóstico a largo plazo en este grupo de pacientes.

Background: High-sensitivity cardiac troponin (hs-cTn) T and I assays are established as crucial tools for the diagnosis of acute myocardial infarction (AMI), as they have been found superior to old troponin assays. However, eventual differences between the assays in prediction of significant coronary lesions and long-term prognosis in patients with acute coronary syndrome (ACS) have not been fully unraveled. Methods: Serum concentrations of hs-cTnT (Roche), hs-cTnI (Abbott), and amino-terminal pro-B-type natriuretic peptide (NT-proBNP; Roche) in 390 non-ST-elevation (NSTE) ACS patients were evaluated in relation to significant coronary lesions on coronary angiography (defined as a stenosis >50% of the luminal diameter, with need for revascularization) and prognostic accuracy for cardiovascular mortality, all-cause mortality, as well as the composite end point of cardiovascular mortality and hospitalizations for AMI or heart failure. Results: The mean+SD follow-up was 2921+168 days. Absolute hs-cTnI concentrations were significantly higher than the hs-cTnT concentrations. The relationship between analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by the area under the ROC curve (AUC), revealed no difference between hs-cTnT [AUC, 0.81; 95% CI, 0.77-0.86] and hs-cTnI (AUC, 0.81; 95% CI, 0.76-0.86; P=NS). NT-proBNP was superior to both hs-cTn assays regarding prognostic accuracy for both cardiovascular and all-cause mortality and for the composite end point during follow-up, also in multivariate analyses. Conclusions: The hs-cTnT and hs-cTnI assays displayed a similar ability to predict significant coronary lesions in NSTE-ACS patients. NT-proBNP was superior to both hs-cTn assays as a marker of long-term prognosis in this patient group.

High-Sensitivity Troponin T vs I in Acute Coronary Syndrome: Prediction of Significant Coronary Lesions and Long-term Prognosis.

BACKGROUND: High-sensitivity cardiac troponin (hs-cTn) T and I assays are established as crucial tools for the diagnosis of acute myocardial infarction (AMI), as they have been found superior to old troponin assays. However, eventual differences between the assays in prediction of significant coronary lesions and long-term prognosis in patients with acute coronary syndrome (ACS) have not been fully unraveled. METHODS: Serum concentrations of hs-cTnT (Roche), hs-cTnI (Abbott), and amino-terminal pro-B-type natriuretic peptide (NT-proBNP; Roche) in 390 non-ST-elevation (NSTE) ACS patients were evaluated in relation to significant coronary lesions on coronary angiography (defined as a stenosis >50% of the luminal diameter, with need for revascularization) and prognostic accuracy for cardiovascular mortality, all-cause mortality, as well as the composite end point of cardiovascular mortality and hospitalizations for AMI or heart failure. RESULTS: The mean (SD) follow-up was 2921 (168) days. Absolute hs-cTnI concentrations were significantly higher than the hs-cTnT concentrations. The relationship between analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by the area under the ROC curve (AUC), revealed no difference between hs-cTnT [AUC, 0.81; 95% CI, 0.77-0.86] and hs-cTnI (AUC, 0.81; 95% CI, 0.76-0.86; P = NS). NT-proBNP was superior to both hs-cTn assays regarding prognostic accuracy for both cardiovascular and all-cause mortality and for the composite end point during follow-up, also in multivariate analyses. CONCLUSIONS: The hs-cTnT and hs-cTnI assays displayed a similar ability to predict significant coronary lesions in NSTE-ACS patients. NT-proBNP was superior to both hs-cTn assays as a marker of long-term prognosis in this patient group.

Non-invasive myocardial work index identifies acute coronary occlusion in patients with non-ST-segment elevation-acute coronary syndrome.

AIMS: Acute coronary artery occlusion (ACO) occurs in ∼30% of patients with non-ST-segment elevation-acute coronary syndrome (NSTE-ACS). We investigated the ability of a regional non-invasive myocardial work index (MWI) to identify ACO. METHODS AND RESULTS: Segmental strain analysis was performed before coronary angiography in 126 patients with NSTE-ACS. Left ventricular (LV) pressure was estimated non-invasively using a standard waveform fitted to valvular events and scaled to systolic blood pressure. MWI was calculated as the area of the LV pressure-strain loop. Empirical cut-off values were set to identify segmental systolic dysfunction for MWI (<1700 mmHg %) and strain (more than -14%). The number of dysfunctional segments was used in ROC analysis to identify ACO. The presence of ≥4 adjacent dysfunctional segments assessed by MWI was significantly better than both global strain and ejection fraction at detecting the occurrence of ACO (P < 0.05). Regional MWI had a higher sensitivity (81 vs. 78%) and especially specificity (82 vs. 65%) compared with regional strain. Logistic regression demonstrated that elevated systolic blood pressure significantly decreased the probability of actual ACO in a patient with an area of impaired regional strain. CONCLUSION: The presence of a region of reduced MWI in patients with NSTE-ACS identified patients with ACO and was superior to all other parameters. The regional MWI was able to account for the influence of systolic blood pressure on regional contraction. We therefore propose that MWI may serve as an important clinical tool for selecting patients in need of prompt invasive treatment.

Sensitive cardiac troponins and N-terminal pro-B-type natriuretic peptide in stable coronary artery disease: correlation with left ventricular function as assessed by myocardial strain.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponins (cTns) measured with sensitive assays provide strong prognostic information in patients with stable coronary artery disease. However, the relationship between these biomarkers and myocardial contractile function, as well as infarct size, in this patient group, remains to be defined. The study population consisted of 160 patients referred to a follow-up echocardiography scheduled 1 year after coronary revascularization. Concentrations of NT-proBNP, high-sensitive cTnT (hs-cTnT) and sensitive cTnI assays were assessed. Left ventricular function was measured as global peak systolic longitudinal strain by speckle tracking echocardiography and infarct size was assessed by late-enhancement MRI. NT-proBNP and sensitive cTnI levels were significantly associated with left ventricular function by peak systolic strain (R-values 0.243 and 0.228, p = 0.002 and 0.004) as well as infarct size (R-values 0.343 and 0.366, p = 0.014 and p = 0.008). In contrast, hs-cTnT did not correlate with left ventricular function (R = 0.095, p = 0.231) and only marginally with infarct size (R = 0.237, p = 0.094). NT-proBNP and sensitive cTnI levels correlate with left ventricular function and infarct size in patients with stable coronary artery disease after revascularization. As opposed to hs-cTnT, NT-proBNP and cTnI seem to be indicators of incipient myocardial dysfunction and the extent of myocardial necrosis.

Early systolic lengthening may identify minimal myocardial damage in patients with non-ST-elevation acute coronary syndrome.

AIMS: Ischaemic myocardial segments tend to stretch as the intraventricular pressure rises steeply during the isovolemic contraction phase, before they contract during ejection. We hypothesized that the time they remain stretched, called duration of early systolic lengthening (DESL), correlates with final infarct size as defined by contrast enhanced magnetic resonance imaging (CE-MRI). We also assessed whether DESL could identify patients with acute coronary occlusion, and compared it with traditional measures for myocardial function. METHODS AND RESULTS: In this retrospective study, 150 consecutive patients with Non-ST-elevation acute coronary syndrome (NSTE-ACS) referred for coronary angiography were included. Speckle tracking echocardiography was performed prior to angiography to determine DESL. The final infarct size was quantified at follow-up 9 ± 3 months after initial admission in 61 patients and echocardiography performed in 143 patients. DESL showed good correlation with the final infarct size (r = 0.67, P < 0.001). Thirteen patients had no visible sign of infarct on CE-MRI (minimal myocardial damage), and DESL was significantly shorter in these patients than in patients with signs of infarct (27 ± 19 vs. 84 ± 41 ms, P < 0.001). Compared with left ventricular ejection fraction, wall motion score index, and global longitudinal strain, DESL showed the best accuracy in detecting patients with minimal myocardial damage, with an area under the receiver operating characteristic curve of 0.92 (0.82 to 0.99, P < 0.001). DESL was more prolonged in patients with coronary occlusions, compared with those without occlusions (86 ± 45 vs. 63 ± 31 ms, P < 0.01). DESL was significantly shorter at follow-up, compared with baseline (P = 0.04). CONCLUSIONS: DESL could identify patients with minimal myocardial damage, differentiate between occlusion and non-occlusion, and may be helpful in the risk stratification of patients with NSTE-ACS.

Early assessment of strain echocardiography can accurately exclude significant coronary artery stenosis in suspected non-ST-segment elevation acute coronary syndrome.

BACKGROUND: Many patients with suspected non-ST-segment elevation acute coronary syndrome (NSTE-ACS) do not have significant coronary artery disease. The current diagnostic approach of repeated electrocardiography and cardiac biomarker assessment requires observation for >6 to 12 hours. This strategy places a heavy burden on hospital facilities. The objective of this study was to investigate whether myocardial strain assessment by echocardiography could exclude significant coronary artery stenosis in patients presenting with suspected NSTE-ACS. METHODS: Sixty-four patients presenting to the emergency department with suspected NSTE-ACS without known coronary artery disease, inconclusive electrocardiographic findings, and normal cardiac biomarkers at arrival were enrolled. Twelve-lead electrocardiography, troponin T assay, and echocardiography were performed at arrival, and all patients underwent coronary angiography. Significant coronary stenosis was defined as >50% luminal narrowing. Global myocardial peak systolic longitudinal strain was measured using speckle-tracking echocardiography. Left ventricular ejection fraction and wall motion score index were calculated. RESULTS: No significant stenosis in any coronary artery was found in 35 patients (55%). Global peak systolic longitudinal strain was superior to conventional echocardiographic parameters in distinguishing patients with and without significant coronary artery stenosis (area under the curve, 0.87). Sensitivity and specificity were calculated as 0.93 and 0.78, respectively, and positive predictive value and negative predictive value as 0.74 and 0.92, respectively. Feasibility of the strain measurements was excellent, with 97% of segments analyzed. CONCLUSIONS: Myocardial strain by echocardiography may facilitate the exclusion of significant coronary artery stenosis among patients presenting with suspected NSTE-ACS with inconclusive electrocardiographic findings and normal cardiac biomarkers.

Strain echocardiography improves risk prediction of ventricular arrhythmias after myocardial infarction.

OBJECTIVES: The aim of this study was to test the hypothesis that strain echocardiography might improve arrhythmic risk stratification in patients after myocardial infarction (MI). BACKGROUND: Prediction of ventricular arrhythmias after MI is challenging. Left ventricular ejection fraction (LVEF) <35% is the main parameter for selecting patients for implantable cardioverter-defibrillator therapy. METHODS: In this prospective, multicenter study, 569 patients >40 days after acute MI were included, 268 of whom had ST-segment elevation MIs and 301 non-ST-segment elevation MIs. By echocardiography, global strain was assessed as average peak longitudinal systolic strain from 16 left ventricular segments. Time from the electrocardiographic R-wave to peak negative strain was assessed in each segment. Mechanical dispersion was defined as the standard deviation from these 16 time intervals, reflecting contraction heterogeneity. RESULTS: Ventricular arrhythmias, defined as sustained ventricular tachycardia or sudden death during a median 30 months (interquartile range: 18 months) of follow-up, occurred in 15 patients (3%). LVEFs were reduced (48 ± 17% vs. 55 ± 11%, p < 0.01), global strain was markedly reduced (-14.8 ± 4.7% vs. -18.2 ± 3.7%, p = 0.001), and mechanical dispersion was increased (63 ± 25 ms vs. 42 ± 17 ms, p < 0.001) in patients with arrhythmias compared with those without. Mechanical dispersion was an independent predictor of arrhythmic events (per 10-ms increase, hazard ratio: 1.7; 95% confidence interval: 1.2 to 2.5; p < 0.01). Mechanical dispersion and global strain were markers of arrhythmias in patients with non-ST-segment elevation MIs (p < 0.05 for both) and in those with LVEFs >35% (p < 0.05 for both), whereas LVEF was not (p = 0.33). A combination of mechanical dispersion and global strain showed the best positive predictive value for arrhythmic events (21%; 95% confidence interval: 6% to 46%). CONCLUSIONS: Mechanical dispersion by strain echocardiography predicted arrhythmic events independently of LVEF in this prospective, multicenter study of patients after MI. A combination of mechanical dispersion and global strain may improve the selection of patients after MI for implantable cardioverter-defibrillator therapy, particularly in patients with LVEFs >35% who did not fulfill current implantable cardioverter-defibrillator indications.

Mitral annular displacement by Doppler tissue imaging may identify coronary occlusion and predict mortality in patients with non-ST-elevation myocardial infarction.

BACKGROUND: Mitral annular displacement (MAD) is a simple marker of left ventricular (LV) systolic function. The aim of this study was to test the hypothesis that MAD can distinguish patients with non-ST-segment elevation myocardial infarctions (NSTEMIs) from those with significant coronary artery disease without infarctions, identify coronary occlusion, and predict mortality in patients with NSTEMIs. MAD was compared with established indices of LV function. METHODS: In this retrospective study, 167 patients with confirmed NSTEMIs were included at two Scandinavian centers. Forty patients with significant coronary artery disease but without myocardial infarctions were included as controls. Doppler tissue imaging was performed at the mitral level of the left ventricle in the three apical planes, and velocities were integrated over time to acquire MAD. LV ejection fraction, global longitudinal strain (GLS), and wall motion score index were assessed according to guidelines. RESULTS: MAD and GLS could accurately distinguish patients with NSTEMIs from controls. During 48.6 ± 12.1 months of follow-up, 22 of 167 died (13%). MAD, LV ejection fraction, and GLS were reduced and wall motion score index was increased among those who died compared with those who survived (P < .001, P < .001, P < .001, and P = .02, respectively). Multivariate Cox proportional-hazards analyses revealed that MAD was an independent predictor of death (hazard ratio, 1.36; 95% confidence interval, 1.07-1.73; P = .01). MAD and GLS were reduced and wall motion score index was increased in patients with coronary artery occlusion compared with those without occlusion (P = .006, P = .001, and P = .02), while LV ejection fraction did not differ (P = .20). CONCLUSIONS: MAD accurately identified patients with NSTEMIs, predicted mortality, and identified coronary occlusion in patients with NSTEMIs.

Sensitive troponin assays and N-terminal pro-B-type natriuretic peptide in acute coronary syndrome: prediction of significant coronary lesions and long-term prognosis.

BACKGROUND: Sensitive troponin assays have substantially improved early diagnosis of myocardial infarction. However, the role of sensitive cardiac troponin (cTn) assays in prediction of significant coronary lesions and long-term prognosis in non-ST-elevation acute coronary syndrome (NSTE-ACS) remains unresolved. METHODS: This prospective study includes 458 consecutive patients with NSTE-ACS admitted for coronary angiography. Serum levels of 4 commercial available sensitive troponin assays were analyzed (Roche high-sensitive cTnT [hs-cTnT; Roche Diagnostics, Basel, Switzerland], Siemens cTnI Ultra [Siemens, Munich, Germany], Abbott-Architect cTnI [Abbott, Abbott Park, IL], Access Accu-cTnI [Beckman Coulter, Nyon, Switzerland]), as well as a standard assay (Roche cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), before coronary angiography. RESULTS: The relationship between the analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by area under the receiver operating characteristic curve, was significantly higher with Roche hs-cTnT, Siemens cTnI Ultra, and Access Accu-cTnI as compared with standard troponin T assay (P < .001 for all comparisons). This difference was mainly caused by increased sensitivity below the 99th percentile. Also, NT-proBNP was associated with the presence of significant coronary lesions. Cardiac troponin values were correlated with cardiac death (primary end point) during 1373 (1257-1478) days of follow-up. In both univariate and multivariate Cox regression analyses, NT-proBNP was superior to both hs-cTnT and cTnI in prediction of cardiovascular mortality. Troponin values with all assays were correlated with the need for repeated revascularization (secondary end point) during follow-up. CONCLUSIONS: Sensitive cTn assays are superior to standard cTnT assay in prediction of significant coronary lesions in patients with NSTE-ACS. However, this improvement is primary caused by increased sensitivity below the 99th percentile. N-terminal pro-B-type natriuretic peptide is superior to cTns in prediction of long-term mortality.