High Bleeding Incidence in Unselected Hospitalized Suspected Non-ST-Segment Elevation Myocardial Infarction Patients Aged Under 65 Years

High bleeding risk (HBR) is commonly encountered among patients with acute coronary syndrome (ACS), and bleeding complications are associated with worse prognosis. Data on bleeding events of patients with ACS are based almost exclusively on percutaneous coronary intervention registries. Enrolling only patients suitable for invasive procedures might have skewed the observed bleeding incidence. We sought to investigate bleeding incidence in unselected patients with ACS. Patients were retrospectively enrolled between January and June 2019 from the emergency department of a tertiary hospital. All consecutive hospitalized adults with suspected non-ST-segment elevation myocardial infarction were included. Data was gathered by a database search and verified using electronic patient records. Bleeding risk was assessed according to the Academic Research Consortium for High Bleeding Risk (ARC-HBR) definition. The primary end point was a composite of post- discharge Bleeding Academic Research Consortium type 2, 3, and 5 bleeding during 1-year follow-up. Of the 209 included patients, 15 (7.2%) suffered a bleeding event. There were more bleeding events among dual antiplatelet therapy (DAPT) users as compared with those without DAPT (10.7% vs 3.1%, p = 0.033). Among HBR patients, 6.1% and in non-HBR patients 8.1% suffered a bleeding event (p = 0.579). Notably, major bleeding (Bleeding Academic Research Consortium type 3) incidence was highest in patients <65 years and without DAPT use. In conclusion, unselected suspected non-ST-segment elevation myocardial infarction patients aged <65 years had surprisingly high bleeding incidence, regardless of ARC-HBR status or DAPT use.

Impact of Intraprocedural Pressure Changes on Hemodynamic Outcome During Self-Expanding TAVR

INTRODUCTION

During the transcatheter aortic valve replacement (TAVR) procedure, hemodynamic measurements can be used to evaluate transcatheter heart valve (THV) performance. We hypothesized that the occurrence of a significant decrease in invasive aortic pressure immediately after annular contact by a self-expanding THV indicates effective annular sealing. This phenomenon could thus be used as a marker for the occurrence of paravalvular leak (PVL).

METHODS

Thirty-eight patients undergoing TAVR procedure with a self-expandable Evolut R or Evolut Pro (Medtronic) valve prosthesis were included in the study. Drop in aortic pressure during valve expansion was defined as a decrease in systolic pressure of 30 mmHg immediately after annular contact. The primary endpoint was the occurrence of more than mild PVL immediately after valve implantation.

RESULTS

A pressure drop was seen in 60.5% (23/38) of patients. More than mild PVL requiring balloon post-dilatation (BPD) was significantly more frequent in patients who did not have a systolic pressure decrease > 30 mmHg during valve implantation (46.7% [7/15] vs. 13.0% [3/23], respectively; p = 0.03). Patients without a systolic pressure decrease > 30 mmHg also had a lower mean cover index on computed tomography analysis (16.2% vs. 13.3%; p = 0.016). The 30-day outcomes were similar between the two groups, and echocardiography at 30 days demonstrated more than none/trace PVL in 21.1% (8/38) of patients, with no difference between the two groups.

CONCLUSION

A decrease in aortic pressure after annular contact is associated with an increased probability of good hemodynamic outcome after self-expanding TAVR implantation. In addition to other methods, this parameter could be used as an additional marker for optimal valve positioning and hemodynamic outcome during the implantation procedure.

Direct Immunoassay for Free Pregnancy-Associated Plasma Protein A (PAPP-A)

Background

Pregnancy-associated plasma protein A (PAPP-A), especially in its noncomplexed form (fPAPP-A), is linked to vulnerable atherosclerotic plaques and risk of cardiac events. An assay for sensitive detection of fPAPP-A has been lacking. Our aim was to develop and validate a direct fPAPP-A assay to meet this need.

Methods

Monoclonal antibodies binding exclusively fPAPP-A were produced by immunizing mice with recombinant PAPP-A. In the optimized immunoassay, we used an fPAPP-A–specific capture antibody together with a lanthanide-chelate–labeled monoclonal antibody recognizing all PAPP-A forms. The assay was evaluated with CLSI guidelines and compared to a 2-assay subtractive fPAPP-A approach. Clinical performance was assessed with acute coronary syndrome patients.

Results

The limits of detection and quantitation were 0.4 mIU/L and 1.3 mIU/L, respectively, and the assay was linear up to 1000 mIU/L (R2 = 0.999). Both serum and heparin plasma were suitable matrices, and the complexed form of PAPP-A caused no significant interference. Correlation between the developed assay and the 2-assay approach was fair (Pearson's r = 0.819). Median concentration in healthy individuals was 1.0 mIU/L. fPAPP-A concentration was higher in patients who had myocardial infarction or died during the 1-year follow-up period than in those who did not (1.13 mIU/L vs 0.82 mIU/L, P = 0.008, model adjusted with age and sex). fPAPP-A measured with this direct assay predicted this end point as well as (follow-up 1 year) or better (30 days) than the 2-assay fPAPP-A alone or in combination with cTnI.

Conclusions

The new assay enables sensitive and reliable measurement of low cardiac-related fPAPP-A concentrations from blood samples.

Trends in occurrence and 30-day mortality of infective endocarditis in adults: population-based registry study in Finland

OBJECTIVES

Infective endocarditis (IE) is a life-threatening disease associated with significant mortality. We studied recent temporal trends and age and sex differences in the occurrence and short-term mortality of IE.

DESIGN

Population based retrospective cohort study.

SETTING

Data of IE hospital admissions in patients aged ≥18 years in Finland during 2005-2014 and 30-day all-cause mortality data were retrospectively collected from mandatory nationwide registries from 38 hospitals.

OUTCOMES

Trends and age and sex differences in occurrence. Thirty-day mortality.

RESULTS

There were 2611 cases of IE during the study period (68.2% men, mean age 60 years). Female patients were significantly older than males (62.0 vs 59.0 years, p=0.0004). Total standardised annual incidence rate of IE admission was 6.33/100 000 person-years. Men had significantly higher risk of IE compared with women (9.5 vs 3.7/100 000; incidence rate ratios [IRR] 2.49; p<0.0001) and difference was most prominent at age 40-59 years (IRR 4.49; p<0.0001). Incidence rate varied from 5.7/100 000 in 2005 to 7.1/100 000 in 2012 with estimated average 2.1% increase per year (p=0.036) and similar trends in both sexes. Significant increasing trend was observed in patients aged 18-29 years and 30-39 years (estimated annual increase 7.6% and 7.2%, p=0.002) and borderline in patients aged 40-49 years (annual increase 3.8%, p=0.08). In older population, IE incidence rate remained stable. The overall 30-day mortality after IE admission was 11.3%. Mortality was similar between sexes, increased with ageing, and remained similar during the study period.

CONCLUSIONS

Occurrence of IE is increasing in young adults in Finland. Men, especially middle-aged, are at higher risk for IE compared with women. Thirty-day mortality has remained stable at 11%, increased with ageing, and was similar between sexes.

Are glycoprotein inhibitors safe during percutaneous coronary intervention in patients on chronic warfarin treatment?

The aim of this study was to evaluate the safety of glycoprotein IIb/IIIa inhibitors (GPIs) during percutaneous coronary intervention (PCI) in patients on chronic warfarin therapy due to atrial fibrillation (AF).We analysed all consecutive AF patients (N = 377, mean age 70 years, male 71%) on warfarin therapy referred for PCI in seven centres. Major bleeding, access site complications and major adverse cardiovascular events were recorded during hospitalisation. A total of 111 patients (29%) received periprocedural GPIs with a wide inter-hospital variation in their use (range 3–68%).The use of GPIs increased with the severity of the disease presentation and 49% of patients with ST-elevation myocardial infarction received GPIs. Mean periprocedural international normalised ratio (INR) of patients who received GPIs was 1.89 (range 1.1–3.3). Major bleeding was more common in the patients treated with GPIs (9.0% vs. 1.5%, p = 0.001) than in those without GPIs, but there was no difference in major adverse cardiovascular events between the groups. In multivariable analysis, use of GPIs (odds ratio [OR]???????????5.1, 95% confidence interval [CI]???????????1.3–20.6, p = 0.02) and old age (OR 1.2, 95% CI 1.0–1.3, p = 0.02) remained as the only independent predictors of major bleeding. Also after adjusting for propensity score, GPIs remained as a significant predictor of major bleeding (OR 3.8, 95% CI 1.03–14.1, p = 0.045). In the GPI group, major bleeding was not predicted by INR level or warfarin pause. GPIs increase the risk of major bleeding events irrespective of periprocedural INR levels and should be used with caution in this fragile patient group.

[Update on Current Care Guidelines. Current Care Guideline: Stable Coronary Artery Disease]

This guideline covers coronary heart disease symptoms, diagnosis and treatment. Stable coronary heart disease refers to a disease in, which patients have stable symptoms and evidence of ischemia or significant stenosis of coronary artery. Diagnosis is based on medical history and exercise test, which is the primary diagnostic test. Coronary angiography is in selected cases necessary to confirm the diagnosis and assess invasive treatment. Pharmacotherapy aims to improve the survival of the patient, relieve symptoms and improve quality of life. The guideline also deals with invasive treatment either with PCI or CABG.

Autoantibody prevalence with an improved immunoassay for detecting cardiac troponin-specific autoantibodies

Cardiac troponin-specific autoantibodies (cTnAAb) can interfere with the measurement of cardiac troponin I (cTnI) by immunoassays used for the diagnosis of myocardial infarction (MI). Here, an improved version of a previous autoantibody assay was validated and used to evaluate the cTnAAb prevalence in a cohort of consecutive chest pain patients presenting to an emergency department.

Admission samples from 510 patients with suspected MI were analyzed in parallel with two sandwich-type cTnAAb assays based on different cTnI epitopes used to capture cardiac troponin-bound cTnAAbs.

Sample-specific backgrounds were lower for the new assay than for the old assay (median 1225 vs. 2693 counts, p<0.001). Net signals of cTnAAb-positive samples were higher for the new assay than for the old assay (median 5076 vs. 3921 counts, p<0.001). Of all patients, 9.2% were cTnAAb-positive for the new assay and 7.3% for the old assay (p=0.013). Previous cardiac problems were not associated with cTnAAb status and cTnAAb status did not correlate with the 12-month outcome.

With our new and more sensitive autoantibody assay, approximately one out of ten patients who presented to the initial cardiac triage had detectable amounts of cTnAAbs in the circulation. Because these cTnAAbs can interfere with state-of-the-art cTnI assays, their high prevalence should be acknowledged by clinical chemists, physicians, and kit manufacturers.

PR depression is useful in the differential diagnosis of myopericarditis and ST elevation myocardial infarction

BACKGROUND

Deviation of the PR segment is a common but often ignored ECG finding in acute myopericarditis, but seems to be rare in the acute phase of ST elevation myocardial infarction (STEMI). Since rapid bedside differential diagnosis of acute myopericarditis and STEMI is essential, we decided to assess the diagnostic power of PR depressions in patients presenting with ST elevations in the emergency room.

METHODS

Thirty-four consecutive patients with acute myopericarditis and 46 STEMI patients presenting with ST elevations fulfilling the criteria for STEMI were included. The first ECG recorded in the emergency room was analyzed with a focus on the PR segment. The diagnoses of myopericarditis and STEMI were ascertained with clinical follow-up together with rise in troponin levels, and in the STEMI patients also with coronary angiography.

RESULTS

In myopericarditis, the most common location for PR depression was lead II (55.9%), while this ECG finding least likely appeared in lead aVL (2.9%). PR depression in any lead had a high sensitivity (88.2%), but fairly low specificity (78.3%) for myopericarditis. The combination of PR depressions in both precordial and limb leads had the most favorable predictive power to differentiate myopericarditis from STEMI (positive 96.7% and negative power 90%).

CONCLUSIONS

Our present observations show that PR segment analysis is a powerful tool in the differential diagnosis of myopericarditis and STEMI. This simple information should be added to the diagnostic workup of patients presenting with ST elevations.

Long-term safety of drug-eluting stents in patients on warfarin treatment

BACKGROUND

The safety of drug-eluting stents (DES) in patients on long-term warfarin treatment has been questioned due to high risk of bleeding complications during prolonged triple (aspirin, clopidogrel, and warfarin) antithrombotic therapy.

METHODS

We analysed the long-term outcome of 415 consecutive warfarin-treated patients who underwent DES (n = 191) or bare-metal (n = 224) stenting in six hospitals.

RESULTS

The mean duration of triple therapy was longer (4.2 ± 3.1 versus 2.1 ± 1.8 months; P < 0.001) in the DES group. The incidence of major adverse cardiovascular and cerebrovascular events was comparable in the DES and bare-metal groups (39.8% versus 42.4%; P = 0.59) during a median follow-up of 3.5 years. Similarly, major bleeding events occurred equally often in both study groups (14.7% versus 12.9%). Six patients in the DES group and seven patients in the bare-metal group suffered stent thrombosis (3.1% versus 3.1%). In the propensity score analyses of 101 matched pairs, the outcome was similar in the two groups.

CONCLUSION

Selective use of DES with a short triple therapy seems to be safe in patients with warfarin therapy. The prognosis of this fragile patient population is quite poor, and major bleeding events are common irrespective of stent type.

Postoperative stroke in patients on oral anticoagulation undergoing coronary artery bypass surgery

OBJECTIVE

Patients on long-term warfarin treatment have an inherent high risk of stroke and here we aimed to identify the determinants of postoperative stroke after coronary artery bypass grafting (CABG) in these patients.

METHODS

A consecutive series of 270 patients on long-term warfarin treatment who underwent isolated CABG in two university hospitals was assessed by logistic regression as well as classification and regression tree (CART) analysis.

RESULTS

Postoperative stroke occurred in 10 patients during in-hospital stay (3.7%). Logistic regression showed that CHADS(2) > 2 (p = 0.036), recent thrombolysis (p < 0.0001) and history of deep vein thrombosis (p = 0.025) were independent predictors of postoperative stroke (area under the ROC curve 0.77). CART analysis showed that CHADS(2) > 2, history of stroke/TIA, no preoperative use of aspirin and preoperative use of low molecular weight heparins were associated with an increased risk of stroke (area under the ROC curve of 0.77).

CONCLUSIONS

Both CART and logistic regression analyses showed that the patient characteristics included in CHADS(2) score are important also in the prediction of postoperative stroke risk. Preoperative antiplatelet treatment may be beneficial in the high risk patients and the preoperative bridging with low molecular weight heparins may even be harmful in this respect.

Usefulness of outpatient bleeding risk index to predict bleeding complications in patients with long-term oral anticoagulation undergoing coronary stenting

Long-term oral anticoagulation (OAC) prevents recurrent thrombosis, pulmonary embolism, and stroke, but it also increases bleeding risk. An outpatient bleeding risk index (OBRI) may help to identify patients at high risk of bleeding complications. The aim of this study was to evaluate the predictive value of OBRI in patients with OAC undergoing percutaneous coronary intervention (PCI). In addition, we analyzed the impact of OBRI on treatment choices in this patient group. Four hundred twenty-one patients with OAC underwent PCI at 6 centers in Finland. Complete follow-up was achieved in all patients (median 1,276 days). Sixty-four patients (15%) had a low bleeding risk (OBRI 0), 319 patients (76%) moderate bleeding risk (OBRI 1 to 2), and 38 (9%) high bleeding risk (OBRI 3 to 4). OBRI had no significant effect on periprocedural or long-term antithrombotic medications, choice of access site, or stent type. During follow-up, the incidence of major bleeding increased (p = 0.02) progressively with higher OBRI category (6.3%, 14.1%, and 26.3%, respectively). Similarly, mortality was highest in patients with high OBRI (14.1%, 20.7%, and 39.5%, p = 0.009, respectively), but rates of major adverse cardiovascular and cerebrovascular events were comparable in the OBRI categories. In conclusion, bleeding risk seems not to modify periprocedural or long-term treatment choices in patients after PCI on home warfarin. In contrast, patients with high OBRI often have major bleeding episodes and this simple index seems to be suitable for risk evaluation in this patient group.

Free vs Total Pregnancy-Associated Plasma Protein A (PAPP-A) as a Predictor of 1-Year Outcome in Patients Presenting with Non–ST-Elevation Acute Coronary Syndrome

Background: The free fraction of pregnancy-associated plasma protein A (FPAPP-A) was found to be the PAPP-A form released to the circulation in acute coronary syndrome (ACS). We estimated the prognostic value of FPAPP-A vs total PAPP-A (TPAPP-A) concentrations in forecasting death and nonfatal myocardial infarction (combined endpoint) in patients with non–ST-elevation ACS.

Methods: We recruited 267 patients hospitalized for symptoms consistent with non–ST-elevation ACS and followed them for 12 months. FPAPP-A, TPAPP-A, C-reactive protein (CRP), and cardiac troponin I (cTnI) were measured at admission; cTnI was also measured at 6–12 h and 24 h. Because of the recently shown interaction between PAPP-A and heparin, we excluded patients treated with any heparin preparations before the admission blood sampling.

Results: During the follow-up, 57 (21.3%) patients met the endpoint (22 deaths and 35 nonfatal myocardial infarctions). According to FPAPP-A (&lt;1.27, 1.27–1.74, &gt;1.74 mIU/L) and TPAPP-A (&lt;1.98, 1.98–2.99, &gt;2.99 mIU/L) tertiles, this endpoint was met by 12 (13.5%), 18 (20.2%), 27 (30.3%) (P = 0.02), and 17 (19.1%), 17 (19.1%), 23 (25.8%) (P = 0.54) patients, respectively. After adjusting for age, sex, diabetes, previous myocardial infarction, and ischemic electrocardiogram (ECG) findings, FPAPP-A &gt;1.74 mIU/L [risk ratio (RR) 2.0; 95% CI 1.0–4.1, P = 0.053), increased cTnI, and CRP ≥2.0 mg/L were independent predictors of an endpoint. The prognostic performance of TPAPP-A was inferior to that of FPAPP-A.

Conclusions: FPAPP-A seems to be superior as a prognostic marker compared to TPAPP-A, giving independent and additive prognostic information when measured at the time of admission in patients hospitalized for non–ST-elevation ACS.

Intravenous administration of low molecular weight and unfractionated heparin elicits a rapid increase in serum pregnancy-associated plasma protein A

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A) has been suggested as a useful diagnostic and prognostic marker in acute coronary syndromes. Because low molecular weight heparin (LMWH) and unfractionated heparin (UFH) are commonly used in these cases, we analyzed the effects of intravenous administration of these heparins on serum PAPP-A concentrations.

METHODS

Serum concentrations of total and free PAPP-A were analyzed in 14 patients on chronic hemodialysis and in 10 coronary angiography patients. Ten of the dialysis patients received standard LMWH anticoagulation at the start of dialysis, and 4 were treated with a heparin-free method. Two of the patients on heparin-free hemodialysis received a reduced LMWH bolus 2 h after the start of dialysis. All angiography patients received UFH at the start of the procedure, and 1 patient received 2 extra boluses of UFH. Serum PAPP-A concentrations were analyzed before and during the dialysis session and during the coronary angiography examination.

RESULTS

A rapid increase in total PAPP-A (median, 25-fold) was seen in all patients within 5 min of administration for both LMWH and UFH boluses. This response was due to an increase in free PAPP-A in the serum. PAPP-A did not increase significantly in the patients who underwent heparin-free hemodialysis. Repeated heparin boluses induced a new PAPP-A release. In vitro addition of heparins to samples of whole blood did not increase PAPP-A concentrations.

CONCLUSIONS

Intravenous administration of heparin induces an intense and rapid increase in free PAPP-A in the serum. We recommend that this effect be considered when PAPP-A is assessed as a biomarker in acute coronary syndromes.

Safety of diagnostic coronary angiography during uninterrupted therapeutic warfarin treatment

Long-term warfarin therapy is assumed to increase bleeding and access site complications after coronary angiography and it is often recommended to postpone invasive procedures to reach international normalized ratio (INR) levels <1.8. To assess the safety and feasibility of diagnostic coronary angiography during uninterrupted warfarin therapy, we retrospectively analyzed all consecutive patients (n = 258) on warfarin therapy referred for diagnostic coronary angiography in 2 centers with long experience in uninterrupted warfarin therapy during coronary angiography and in 1 center with a policy of preprocedural warfarin pause. An age- and gender-matched control group (n = 258) with similar disease presentation (unstable or stable symptoms) was collected from each center. Radial access was used in 56% of patients in the warfarin group and in 60% of controls (p = 0.21). There was no difference in access site and bleeding complications (1.9% vs 1.6%) or major adverse cardiovascular and cerebrovascular events (0.4% vs 0.8%) between the warfarin group and their controls. Warfarin was interrupted in 80 patients (31%), and bridging therapy was used in 24 of these patients (30%). INR levels were higher in the uninterrupted warfarin group (2.3 vs 1.9, p <0.001), but the incidence of access site complications was not higher (1.7%) than in patients (n = 80) with a warfarin pause (2.5%) or in patients with pause and bridging therapy (8.3%). Need for blood transfusions (n = 2) occurred only in patients with bridging therapy. Access site complications were more common in the 22 patients with supratherapeutic anticoagulation (INR >3) than in patients with therapeutic periprocedural INR (9.1% vs 1.5%, p <0.05). In conclusion, a simple strategy of performing coronary angiography during uninterrupted therapeutic warfarin anticoagulation is a tempting alternative to bridging therapy and is likely to lead to considerable cost savings.

Detection of proximal coronary occlusion in acute coronary syndrome: a feasibility study using computerized electrocardiographic analysis

BACKGROUND

Rapid identification of a proximal occlusion site of a major coronary artery is of paramount importance in the care of myocardial infarction (MI). It is increasingly recognized that routine electrocardiogram (ECG) can be used for that purpose, provided that expert interpretation is available. Computer-based signal analysis has potential to enhance early ECG interpretation but its performance must be validated against manual algorithms. We therefore set out to develop a computer-assisted model to detect proximal occlusion of the left anterior descending coronary artery (LAD) in patients with suspected acute coronary syndrome (ACS).

METHODS

Based on manual anatomical interpretation of the ECG, obtained from 216 consecutive patients who were admitted due to suspected ACS, an automatic computerized ECG model to detect LAD occlusion was constructed. Agreement between manual evaluation of the ECG by two cardiologists and a computerized ECG algorithm to detect occlusion of the LAD and the site of occlusion was determined.

RESULTS

Using an expert electrocardiographer's anatomical interpretation as the gold standard, the computer model recognized patients fulfilling ECG criteria for any occlusion of the LAD with a specificity of 99% and a sensitivity of 67% (kappa= 0.71). However, proximal LAD occlusion was detected with 100% specificity and 86% sensitivity (kappa= 0.72). The computer program detected a distal occlusion in the LAD with a specificity of 99% and a sensitivity of 40% (kappa= 0.72).

CONCLUSIONS

Computerized anatomical interpretation of the ECG is feasible and allows detection of a proximal LAD occlusion with excellent accuracy.

Safety and efficacy of combined antiplatelet-warfarin therapy after coronary stenting

AIM

The aim of this study was to evaluate the antithrombotic treatment adopted after coronary stenting in patients requiring long-term anticoagulation.

METHODS AND RESULTS

We analysed retrospectively all consecutive patients on warfarin therapy (n = 239, mean age 70 years, men 74%) who underwent percutaneous coronary intervention (PCI) in 2003-04 in six hospitals. An age- and sex-matched control group with similar disease presentation (unstable or stable symptoms) was selected from the study period. Primary endpoint was defined as the occurrence of death, myocardial infarction, target vessel revascularization, or stent thrombosis at 12 months. Warfarin treatment was an independent predictor of both primary endpoint (OR 1.7, 95% CI 1.0-3.0, P = 0.05) and major bleeding (OR 3.4, 95% CI 1.2-9.3, P = 0.02). Triple therapy with aspirin and clopidogrel was the most common (48%) option in stented patients in warfarin group, and there was a significant (P = 0.004) difference between the drug combinations in stent thrombosis with the highest (15.2%) incidence in patients receiving warfarin plus aspirin combination.

CONCLUSION

Our study shows that the prognosis is unsatisfactory in warfarin-treated patients irrespective of the drug combination used. Aspirin plus warfarin combination seems to be inadequate to prevent stent thrombosis.

Pregnancy-associated plasma protein A: a biomarker in acute ST-elevation myocardial infarction (STEMI)

BACKGROUND

Elevated circulating levels of pregnancy-associated plasma protein A (PAPP-A), a novel marker of atherosclerotic plaque instability, are associated with increased risk of future cardiac events in patients with acute coronary syndromes (ACS). However, little is known of the kinetics or clinical significance of circulating PAPP-A after plaque rupture in acute ST-elevation myocardial infarction (STEMI).

AIM

To evaluate the 48-hour release of pregnancy-associated plasma protein A (PAPP-A) and its association with 12-month outcome in patients with acute ST-elevation myocardial infarction (STEMI).

METHODS

Sixty-two consecutive STEMI patients were included (40 men and 22 women, median age 67.5 years (range 34-84)), of whom 54 (87.1%) received reperfusion therapy. PAPP-A was measured at admission and 6-12, 24 and 48 hours thereafter. In 14 patients, samples were obtained also at 1, 2 and 4 hours.

RESULTS

There was an early peak of circulating PAPP-A during the first 12 hours from symptom onset, followed by rapid normalization. A second, late PAPP-A elevation was noticed in 20/62 patients (32.3%). Admission PAPP-A >10.0 mIU/L (highest tertile) was associated (P = 0.049) with increased 12-month risk of cardiovascular death or non-fatal myocardial infarction. Moreover, the combination of failed early reperfusion together with late PAPP-A elevation was strongly (7/13 versus 10/49 patients, P = 0.016) associated with adverse outcome. Admission PAPP-A did not correlate with admission C-reactive protein or cardiac troponin I.

CONCLUSIONS

PAPP-A is elevated early in STEMI and then declines rapidly, a pattern consistent with release from the ruptured plaque. The variability of PAPP-A kinetics at 48 hours reflects the success of reperfusion. This study also shows that PAPP-A may have prognostic value in STEMI.

Comparative accuracy of manual versus computerized electrocardiographic measurement of J-, ST- and T-wave deviations in patients with acute coronary syndrome

Accurate and rapid electrocardiographic interpretation is of crucial importance in acute coronary syndrome (ACS). Computerized electrocardiographic algorithms are often used in out-of-hospital settings. Their accuracy should be carefully validated in ACS, particularly in ST-elevation myocardial infarction. This study evaluated the comparative accuracy of lead-specific computer-based versus manual measurements of the J-point, ST-segment, and T-wave deviations in standard 12-lead electrocardiograms (ECGs) (excluding lead aVR). Sixty-nine consecutive patients with suspected ACS were included. The interobserver reliability in the determination of ST-segment deviation>or=0.2 mV in leads V2 and V3 was very good (kappa=0.94 and 0.93, respectively). Agreement between a cardiologist and the computer regarding ST elevation>or=0.2 mV in lead V2 was moderate (kappa=0.72) and in V3 was very good (kappa=0.85). For ST depression or elevation>or=0.05 mV in lead LIII, agreement was good and moderate (kappa=0.79 and 0.51, respectively). Bland-Altman analysis demonstrated clinically acceptable limits of agreement comparing measurements of the J point and the T wave, but clinically inadequate limits of agreement with respect to ST-segment deviation, between the electrocardiographer and the computer. The optimal cut-off points were 0.115 mV (sensitivity 89%, specificity 98%) for the computer program to detect ST elevation>or=0.2 mV and 0.045 mV (sensitivity 74%, specificity 99%) for revealing ST elevation>or=0.1 mV. It was found that automatically measured ST-segment deviations were smaller than those manually measured. In conclusion, a correction should be performed to obtain optimal results in the automated analysis of ECGs, because the results have important implications for clinical decision making.

Comparison of Cardiac Troponin I Immunoassays Variably Affected by Circulating Autoantibodies

Background: We recently provided evidence that circulating autoantibodies against cardiac troponin I (cTnI) or the troponin complex cause negative interference in cTnI immunoassays. By comparing three cTnI immunoassays, we further explored the phenomenon of circulating autoantibodies and their consequences in patient samples.

Methods: We developed a cTnI immunoassay with a novel assay design using three antibodies, two of which bind epitopes outside the stable, central part of cTnI. Samples from 541 chest pain patients were measured with the new cTnI assay and with a first-generation cTnI assay (Innotrac Aio cTnI) using a conventional midfragment assay design. Using another sample cohort, we also compared the new assay with a second-generation cTnI assay (Access AccuTnI).

Results: The analytical detection limit of the new cTnI assay was 0.012 μg/L, and the lowest concentration giving a total imprecision (CV) of 10% was 0.060 μg/L. The mean difference (95% limits of agreement) between the new cTnI and Aio cTnI assays was larger in admission samples (21.0%; −107.8% to 149.7%) than in samples taken 6–12 h (12.8%; −61.5% to 87.2%) and 24 h after admission (3.0%; −71.3% to 77.4%; P &lt;0.001). With the lowest concentrations giving 10% CV (0.22 μg/L for Aio cTnI) used as cutoffs, 14.3% (n = 76) of admission samples were positive only with the new assay, whereas 13.5% (n = 72) were positive with both assays. Of samples taken at 6–12 and 24 h, 10.2% (n = 31) and 8.3% (n = 29) were positive only with the new assay. ROC curve analysis of admission samples showed a significantly higher area under the curve for the new cTnI assay (0.940) than for the Aio cTnI assay (0.846; P &lt;0.001). The new cTnI assay gave generally lower results than the AccuTnI assay; the mean (95% limits of agreement) differences were −58.9% (−151.8% to 34.0%) in admission samples. In samples with severe interference from autoantibodies, median ratios between the new assay and AccuTnI were higher than in samples with no apparent troponin autoantibodies (0.875 vs 0.481; P&lt;0.001).

Conclusions: The new cTnI assay, which is based on a novel antibody combination different from the conventional midfragment antibody approach, offers improved detection of cTnI in samples containing troponin autoantibodies.

Improved early risk stratification and diagnosis of myocardial infarction, using a novel troponin I assay concept

BACKGROUND

We evaluated the clinical performance of a novel cardiac troponin I (cTnI) assay specifically designed to improve the very early risk stratification in acute coronary syndromes.

SUBJECTS AND METHODS

Serum and plasma samples (taken 0, 6-12 h and 24 h after admission) from 531 patients with suspected acute coronary syndrome were studied using a novel investigational cTnI assay, reference cTnI assay and myoglobin. The lowest cTnI concentration giving a total assay imprecision of 10% was used as the positive myocardial infarction (MI) cut-off value.

RESULTS

At the time of admission, the investigational assay was positive in 27.9% of the patients, the reference cTnI assay was positive in only 17.5% (P < 0.001) and myoglobin in 24.1% (P = 0.067). Receiver operating characteristic (ROC) curve analysis for the detection of myocardial injury on admission gave area-under-curve (AUC) values of 0.937, 0.775 and 0.762, respectively (P < 0.001). Of those MI patients who presented within 3 h of symptom onset, 50.0% were identified by the investigational assay at the time of presentation, compared with 44.2% by myoglobin (P = 0.791) but only 11.5% by the reference assay (P < 0.001).

CONCLUSIONS

The novel cTnI assay considerably improves the performance of cTnI as an early rule-in biomarker for MI.

Circulating pregnancy-associated plasma protein a predicts outcome in patients with acute coronary syndrome but no troponin I elevation

BACKGROUND

Risk stratification in troponin (cTn)-negative acute coronary syndrome (ACS) remains a clinical challenge. We investigated the predictive value of circulating pregnancy-associated plasma protein A (PAPP-A), a novel marker of atherosclerotic plaque activity, in these patients.

METHODS AND RESULTS

Two hundred consecutive hospitalized ACS patients were included, of whom 136 (69 men and 67 women; mean+/-SD age, 66+/-16 years) remained cTnI-negative for up to 24 hours. PAPP-A was measured at admission, 6 to 12 hours, and 24 hours. During 6-month follow-up, 26 (19.1%) of the cTnI-negative patients reached a primary end point (cardiovascular death, myocardial infarction, or revascularization). At a cutoff level of 2.9 mIU/L, elevated PAPP-A was an independent predictor of adverse outcome (adjusted risk ratio [RR], 4.6; 95% confidence interval, 1.8 to 11.8; P=0.002). Another independent predictor was admission CRP >2.0 mg/L (RR, 2.6; P=0.03).

CONCLUSIONS

Measurement of plasma PAPP-A, a zinc-binding matrix metalloproteinase, is a strong independent predictor of ischemic cardiac events and need of revascularization in patients who present with suspected myocardial infarction but remain troponin negative.

Cardiac decompensation during an ischemic event weakens the predictive power of myocardial injury markers

Our objection was to find determinants of long-term outcome in routine data collected for differential diagnosis of suspected acute myocardial infarction. Study population consisted of 263 discharged patients who were initially hospitalized for differential diagnosis of suspected acute myocardial infarction between October 1992 and January 1993. Follow-up time for all cause and cardiac mortality was 5 years. The variables studied as predictors of outcome were computerized ECG, peak creatine kinase isoenzyme MB, peak troponin I, radiographic evidence of pulmonary congestion (cardiac decompensation), treatment for hyperlipidemia, hypertension or diabetes, smoking, previous myocardial infarction, age and gender. Total mortality was 32% at 5 years, of which 77% (64/83) was of cardiac origin. Pulmonary congestion in chest X-ray was the most powerful predictor of outcome (RR=3.3, 95% CI=2.0-5.2, P<0.001). In multivariate analysis congestion (RR=3.3, CI=2.0-5.2) was the only independent predictor of 5-year total mortality in addition to age (RR=1.06, CI=1.04-1.08). These two variables together with previous myocardial infarction (RR=1.9, CI=1.2-3.1) and hyperlipidemia (RR=2. 0, CI=1.1-3.5) were independent predictors of cardiac mortality. Radiographic evidence of cardiac decompensation during hospitalization is a strong and independent predictor of long-term outcome in unselected patients with suspected AMI. The predictive power of cardiac markers is confined to patients without pulmonary congestion.

Level of circulating phospholipase A2 in prediction of the prognosis of patients with suspected myocardial infarction

OBJECTIVES

Atherosclerotic lesions result from inflammatory-proliferative responses of the endothelium and smooth muscle of the arterial wall. Poor prognosis of acute myocardial infarction (AMI) patients has been associated with elevated levels of acute phase proteins including C-reactive protein. We investigated the significance of circulating phospholipase A2 in the long-term prognosis of suspected AMI patients.

METHODS

The concentration of phospholipase A2 was measured by an immunoassay in sera of 100 suspected AMI patients. Admission phospholipase A2 95 % fractile outliers were excluded to eliminate the effect of acute infectious diseases. The total and atherosclerotic mortalities were followed for a 4-year period.

RESULTS

The most powerful prognostic limit for both admission (p = 0.02, RR = 2.6 and 95% CI = 1.2 to 5.6) and maximal (p = 0.06, RR = 2.4 and 95% CI = 0.96 to 5.9) phospholipase A2 groups was > or =8 microg/l. The admission phospholipase A2 level had an independent prognostic significance for atherosclerotic mortality (p = 0.04, RR = 2.4 and CI = 1.02 to 5.8) in multivariate analysis with CK-MB and age.

CONCLUSIONS

The elevated serum phospholipase A2 level at admission is an independent predictor of long-term atherosclerotic mortality in patients with suspected AMI. The prognostic significance of phospholipase A2 weakens during hospitalisation concomitant to the onset of the acute inflammatory response to myocardial injury.

Prediction of short-term outcome in patients with suspected myocardial infarction

STUDY OBJECTIVE

Although specific cardiac injury markers have enhanced early patient classification, the ECG remains a necessary investigation in the acute phase of chest pain. Combined use of both tests could further improve the diagnostic and prognostic accuracy.

METHODS

We studied 311 consecutive patients who came to the emergency department of a regional referral hospital for the differential diagnosis of acute chest discomfort. The admission ECG was classified using an automated interpretation program and tested together with elevated admission creatine kinase isoform MB (CK-MB) and cardiac troponin I (TnI) concentration for prediction of final myocardial injury (44%) and in-hospital mortality (14%).

RESULTS

Combining the information from the admission ECG and cardiac markers, the sensitivity for becoming final myocardial injury (maximal CK-MB >/=11 microg/L) was 90% and specificity 61%. The proportion of false-negative results (10%) was independent of symptom duration. Age, positive ECG findings, and increased admission TnI levels were predictive for in-hospital mortality.

CONCLUSION

The commonly available biochemical and ECG criteria allow risk stratification of patients with a suspected acute ischemic event. The data analysis can easily be automated and is independent of patient delay.

Is routine echocardiography useful in patients hospitalized for chest pain? Evidence of areal myocardial dysfunction detected only by echocardiography

To assess the diagnostic value of routine two-dimensional echocardiography in the coronary care unit setting, we studied 81 unselected patients admitted for acute chest pain. Using electrocardiography (ECG), clinical history and serum markers of myocardial injury, the patients were retrospectively diagnosed as having had definite acute myocardial infarction (AMI) with (n=13) or without (n=31) previous infarction, possible AMI with (n=14) or without (n=15) previous infarction, and non-coronary cardiac or other causes of chest pain (n=8). Abnormal wall motion was observed in 75/77 patients with a cardiac origin of symptoms (sensitivity 97%), and there were no false-positive wall motion findings. In the 73 patients who were finally diagnosed with coronary artery disease (CAD), echocardiography showed wall motion abnormality in at least one additional coronary territory area in which there were no diagnostic ECG changes for 56% of patients with CAD (41/73) (P<0. 001). These areas were considered to be indicative of the presence of myocardium at risk for future cardiac events. We conclude that in addition to being a sensitive and accurate tool for detection of ischaemic wall motion abnormalities, two-dimensional echocardiography can give valuable information about the area of myocardium at risk. Therefore, therapeutic decisions can be affected by the findings of the routine echocardiographic examination, which is recommended even in unselected coronary care unit patients.

Epidemiological classification of acute myocardial infarction: time for a change?

AIMS

The classification of an acute ischaemic cardiac event is traditionally based on cardiac enzymes, electrocardiography (ECG) and clinical symptoms. The impact of new specific cardiac markers on the diagnostic classification of suspected acute myocardial infarction remains poorly studied. We therefore set out to compare the diagnostic and prognostic information provided by the MONICA code and a patient classification based on the maximal level of creatine kinase MB isoenzyme. The significance of typical pain and various ECG algorithms were separately analysed.

METHODS AND RESULTS

The study population consisted of 311 consecutive patients who were evaluated for suspected acute myocardial infarction in a regional referral hospital. Patients were retrospectively classified according to the MONICA criteria, by a simplified code combining symptoms and creatine kinase MB, and solely using the maximal creatine kinase MB concentration. Total mortality was followed for 1 and 5 years. The creatine kinase MB based classification was shown to be the strongest predictor of mortality (OR=2.8-3.7, p<0.001) for outcome both at 1 and 5 years. Typical pain and a positive Minnesota ECG had no prognostic relevance. However, an analysis algorithm of the admission ECG was predictive of 1- and 5-year survival.

CONCLUSIONS

The epidemiological classification of suspected acute myocardial infarction could be based solely on a specific cardiac marker, such as creatine kinase MB mass. This approach contains prognostic information and is accurate enough for the structured diagnosis of acute myocardial infarction. Other outcome predictors could be used to identify patient subgroups and assess therapy.

Computer-assisted electrocardiography in structured diagnosis of acute myocardial infarction

The purpose of this study was to investigate the applicability of computerized electrocardiogram interpretation in classifying patients with suspected acute myocardial infarction. Computerized acquisition and analysis of the 12-lead electrocardiogram can increase the consistency and reduce the workload of patient classification. The serial electrocardiograms of 311 consecutive patients with suspected myocardial infarction were studied and a new computerized myocardial infarction (CMI) electrocardiographic classification was developed and compared with one commercially available and two manual codes. Statistically, there was almost no correlation between the four ECG codes. Compared with the WHO enzymatic criteria, the sensitivity of the CMI code toward detecting definite and possible infarction was 69.2% and 29.8% with a specificity of 62.1% and 79.7%, respectively. In subjects without previous infarction (n = 214) the sensitivity of the CMI code for definite enzymatic infarction was 71.9% and specificity 77.6%. Substituting the CMI for the Minnesota code had no effect on patient classification by the WHO MONICA criteria in 78% of patients with first infarction. Judged by cardiac macromolecular leakage, all electrocardiographic classifications of possible infarction were poorly correlated with myocardial tissue injury. We have developed a new computerized coding system to detect electrocardiographic myocardial infarction. The structure of the code allows interactive redefinition of criteria to meet user-defined needs. However, because of the weak relationship between electrocardiographic and biochemical criteria of myocardial injury, the role of ECG in the diagnostic classification of acute ischemic syndromes should be re-evaluated.

Automated electrocardiographic scores to estimate myocardial injury size during the course of acute myocardial infarction

The automated ST-elevation score at admission and maximal QRS score during hospitalization provide good estimates of biochemical injury size during the course of first myocardial infarction. Being easily computerized, such scores could be used routinely to monitor the effect of injury-limiting therapy.