12-lead ST-segment Research Articles

Updated Practice Standards for ECG Monitoring: Impact at the Bedside

Any trigger for notifying the health care provider depends on the patient, as well as the expectations for a given setting. Patients vary in their responses to arrhythmias. A consistent message is that any hemodynamically unstable patient should have continuous electrocardiographic (ECG) monitoring. Each unit should consider having preset default heart rate parameters to guide provider notification. These decisions are based on discussion with all stakeholders, including providers and nurses.Consider why your patient may have an elevated cardiac troponin level and no chest pain. Does the patient have neuropathy and, therefore, may not sense angina? Is the patient unable to communicate because of impaired mental status, a language barrier, intubation, or sedation? If the answer to any of these questions is yes, your patient may benefit from continuous ST-segment monitoring. The current highest recommendation for continuous ST-segment monitoring is a IIa (ie, it is reasonable to perform the procedure, but more evidence is needed) in selected patients in a nursing unit with technology for continuous 12-lead ST-segment monitoring and related education and protocols that facilitate reduction of false and nonactionable alarm signals.Because the QT interval can often be measured successfully in all leads, prioritize monitoring the ST segment in the lead with known ST-segment depression or elevation. For example, if the patient had ST-segment changes in a particular lead during a myocardial infarction or balloon inflation during percutaneous coronary intervention, choose that lead; if the patient returns after a successful revascularization, select the lead in which the patient had previously demonstrated ST changes. If the patient is having wide QRS tachycardia, monitor lead V1 to distinguish ventricular tachycardia from supraventricular tachycardia with aberrancy.Dispelling this belief requires a change in unit culture. This change includes considering other types of monitoring such as continuous pulse oximetry instead of ECG monitoring using telemetry. Also consider changing the name of a unit from telemetry unit to progressive care unit or step-down unit. Patients may not need telemetry monitoring on these units, but still need qualified nurses who can provide care for complex airway issues and vascular procedures.

Estimation performance of a reduced lead system during continuous 12-lead ECG ST-segment monitoring

BackgroundReduced lead systems utilizing patient-specific transformation weights have been reported to achieve superior estimates than those utilizing population-based transformation weights. We report upon the effects of ischemic-type electrocardiographic changes on the estimation performance of a reduced lead system when utilizing patient-specific transformation weights and population-based transformation weights. MethodA reduced lead system that used leads I, II, V2 and V5 to estimate leads V1, V3, V4, and V6 was investigated. Patient-specific transformation weights were developed on electrocardiograms containing no ischemic-type changes. Patient-specific and population-based transformations weights were assessed on 45 electrocardiograms with ischemic-type changes and 59 electrocardiograms without ischemic-type changes. ResultsFor patient-specific transformation weights the estimation performance measured as median root mean squared error values (no ischemic-type changes vs. ischemic-type changes) was found to be (V1, 27.5 μV vs. 95.8 μV, P<.001; V3, 33.9 µV vs. 65.2 µV, P<.001; V4, 24.8 μV vs. 62.0 μV, P<.001; V6, 11.7 μV vs. 51.5 μV, P<.001). The median magnitude of ST-amplitude difference 60 ms after the J-point between patient-specific estimated leads and actual recorded leads (no ischemic-type changes vs. ischemic-type changes) was found to be (V1, 18.9 μV vs. 61.4 μV, P<.001; V3, 14.3 μV vs. 61.1 μV, P<.001; V4, 9.7 μV vs. 61.3 μV, P<.001; V6, 5.9 μV vs. 46.0 μV, P<.001). ConclusionThe estimation performance of patient-specific transformations weights can deteriorate when ischemic-type changes develop. Performance assessment of patient-specific transformation weights should be performed using electrocardiographic data that represent the monitoring situation for which the reduced lead system is targeted.

Prehospital 12-lead ST-segment monitoring improves the early diagnosis of acute coronary syndrome

Aims/MethodsWe studied 620 patients who activated “911” for chest pain symptoms to determine the sensitivity and specificity of 12-lead electrocardiogram (ECG) ST-segment monitoring in the prehospital period (PH ECG) for diagnosing acute coronary syndrome (ACS) and to assess whether the addition of PH ECG signs of ischemia/injury to the initial hospital 12-lead ECG obtained in the emergency department would improve the diagnosis of ACS. ResultsThe sensitivity and specificity of the PH ECG were 65.4% and 66.4%. There was a significant increase in sensitivity (79.9%) and decrease in specificity (61.2%) when considered in conjunction with the initial hospital ECG (P < .001). Those with PH ECG ischemia/injury were more than 2.5 times likely to have an ACS diagnosis than those who had no PH ECG ischemia/injury (P < .001). ConclusionsPrehospital ECG data obtained with 12-lead ST-segment monitoring provides diagnostic information about ACS above and beyond the initial hospital ECG.

Cardiovascular Effects of Cocaine

The use of cocaine has evolved from chewing the leaves of the Erythroxylon coca bush thousands of years ago, to purification of cocaine hydrochloride over 100 years ago and its use in tonics and elixirs (at one time in popular cola drinks), to insufflating and injecting the fine, white, water-soluble, powder form, to a smokable freebase form called “crack,” which became popular in the 1980s.1 In 2007, 2.1 million Americans had recent cocaine use; 1.6 million met criteria for cocaine dependence or abuse.1 Cocaine accounted for 31% of all visits to the emergency department related to drug misuse or abuse.1 From 1971 to 1987, the incidence of deaths caused by cocaine overdose increased 20-fold in Dade County, Florida.2 In a consecutive series of 233 emergency visits by cocaine-using patients, 56% presented with cardiovascular complaints, including 40% with chest pain.3 A minority of these patients have acute myocardial infarction (MI) (≈6%),4,–,7 and overall mortality is low (<1%).3,–,5,8,–,10 However, cocaine is associated with a number of cardiovascular diseases, including MI, heart failure, cardiomyopathies, arrhythmias, aortic dissection, and endocarditis. Identifying patients with acute disease is challenging. This review describes the relationship between cocaine and various cardiovascular diseases, as well as appropriate diagnostic evaluation and therapies. ### Molecular Cocaine stimulates the sympathetic nervous system by inhibiting catecholamine reuptake at sympathetic nerve terminals,11,12 stimulating central sympathetic outflow,11 and increasing the sensitivity of adrenergic nerve endings to norepinephrine (Figure 1).12 Cocaine also acts like a class I antiarrhythmic agent (local anesthetic) by blocking sodium and potassium channels, which depresses cardiovascular parameters.13 Of these 2 primary, opposing actions, enhanced sympathetic activity predominates at low cocaine doses, whereas the local anesthetic actions …

The value of the ECG for decision-making at first medical contact in the patient with acute chest pain.

Background/Objectives. Rapid risk stratification of the patient with acute chest pain is essential to select the best management. We investigated the value of the ECG at first medical contact to determine size of the ischaemic myocardial area and thereby severity of risk.Methods. In 386 patients with acute chest pain, ECG findings were correlated with the coronary angiogram. Using ST-segment deviation patterns the location of the coronary culprit lesion was predicted and thereby size of the area at risk. Four groups of patients were present. Those with a narrow QRS and a total 12-lead ST-segment deviation score of >/=5 mm (group 1) or </=4 mm (group 2); a QRS width of >/=120 ms (group 3), and patients with previous coronary bypass grafting (CABG) or percutaneous coronary intervention (PCI) (group 4).Results. Correct coronary culprit lesion localisation was possible in 84% of the 185 patients in group 1, 40% of the total cohort. Accurate prediction was not possible in most patients in groups 2, 3 and 4, in spite of extensive coronary artery disease in group 3 and 4. Conclusions. Using the 12-lead ECG the size of the myocardial area at risk can be accurately predicted when the total ST-segment deviation score is >/=5 mm, allowing identification of those in need of a PCI. In most patients with bundle branch block, previous CABG or PCI, the ECG can not localise the culprit lesion. This approach simplifies and accelerates decision-making at first medical contact. (Neth Heart J 2010;18:301-6.).

The ECG in localizing the culprit lesion in acute inferior myocardial infarction: a plea for lead V4R?

This editorial refers to ‘Distinguishing the right coronary artery from the left circumflex coronary artery as the infarct-related artery in patients undergoing primary percutaneous coronary intervention for acute inferior myocardial infarction’ by N.J. Verouden et al., on page 1517 The electrocardiogram (ECG) is being used for decades as a reliable and inexpensive tool to diagnose acute myocardial infarction in the patient with chest pain. More recently, an emphasis has been made on ECG features that allow better identification of the coronary occlusion site and thereby better estimation of the size of the area at risk, which is important for selection of the preferred type of reperfusion. On average the left anterior descending coronary artery supplies 50% of blood flow and the right coronary artery (RCA) and circumflex (Cx) coronary artery each supply 25% of blood flow to the left ventricular myocardium. In addition, RCA irrigates most of the right ventricle. The closer the occlusion site to the origin of the coronary artery, the larger the ischaemic area and the greater the necessity of a rapid reperfusion attempt. The ECG findings considered to be helpful to localize the occlusion site in the culprit coronary artery have been described by several authors and are summarized elsewhere. 1 In the current issue of the journal, Verouden et al. looked at the value of the standard 12-lead ECG to distinguish the RCA from the Cx coronary artery as an infarct-related vessel in a large series of patients with acute inferior MI undergoing primary percutaneous coronary intervention shortly thereafter. 2 ST-segment elevation in lead III more than in lead II, combined with ST-segment depression in lead I or aVL was used as a marker, suggesting that the culprit lesion was located in RCA. The study is important because of the large number of patients and the short time interval between the 12-lead ECG and the coronary angiogram. The findings can be summarized that using this ECG algorithm a correct diagnosis as to the coronary occlusion site did not reach a pre-specified sensitivity threshold of 90% in the whole group. Of interest is that when the authors applied algorithms published by other investigators using ST-segment deviation in the extremity leads, even lower sensitivity was observed. Only in the case of a total 12-lead ST-segment deviation score of more than 18.5 mm, a sensitivity of more than 90% was found. We are not informed about the accuracy of the algorithm in relation to the degree of ST-segment deviation. Is there a critical threshold of

Continuous ST-Segment Monitoring: 3 Case Studies in Progressive Care

Continuous ST-Segment Monitoring: 3 Case Studies in Progressive Care

Serial snapshot electrocardiograms and continuous 12-lead ST-segment electrocardiographic monitoring for the prediction of intravenous thrombolysis outcome in patients with ST-segment elevation myocardial infarction

We compared the effectiveness of serial snapshot ECGs (S-ECG) and continuous 12-lead ST-segment ECG monitoring (C-ECG) for the prediction of intravenous thrombolysis outcome in 786 patients with ST-segment elevation myocardial infarction. It was found that S-ECG overestimated thrombolysis success over C-ECG by 7.1%. By 1-year patients who were diagnosed as having successful thrombolysis by S-ECG but not by C-ECG were at significantly higher risk of 1-year cardiac death than those who were classified as having successful thrombolysis by both ECG methods, and were at similar risk of 1-year cardiac death than those who were classified as having failed thrombolysis by both ECG methods.

Estimated body surface potential maps in emergency department patients with unrecognized transient myocardial ischemia

Background We report on 5 patients who presented to the emergency department (ED) with chest pain, had negative serum troponin levels, and were discharged with a presumed noncardiac diagnosis. Thereafter, retrospective analysis of Holter monitoring data recorded for a clinical trial revealed ST events indicative of transient myocardial ischemia that was unrecognized clinically. Study Aim The purpose of this analysis was to determine whether initial body surface potential maps estimated from optimal ischemia electrode sites estimated body surface potential map (EBSPM) showed signs of ischemia in the missed ischemia group that could have prevented misdiagnosis. Methods This is a secondary analysis of data from a prospective clinical trial in which patients were attached to 2 Holter monitor devices for simultaneous recordings. One Holter device recorded a standard Mason-Likar 12-lead electrocardiogram (ECG) and the other recorded a 10-electrode lead set considered optimal for ischemia detection. A body surface potential map was then estimated from the optimal lead set. Results At 1 year, 2 of the 5 patients with missed ischemia died and a third had an acute myocardial infarction (MI) (40% mortality, 60% death/nonfatal MI). In comparison, 1-year mortality was 5.7% in 159 similar patients treated for unstable angina at the same institution over the same period ( P = .037). The initial standard ECG showed no abnormalities in 3 patients and showed left ventricular hypertrophy in 1. The fifth patient with a history of recent MI had slight ST elevation in leads III and aVF and Q waves that were considered indicative of recent (not acute) MI. EBSPM data recorded at the time of ED presentation matched the standard ECG (normal in 3, left ventricular hypertrophy or inconclusive in 2). During transient ischemia, all 5 EBSPMs showed areas of ischemia overlapping with standard electrode sites. Conclusion Patients evaluated in the ED for chest pain are at high risk for death or nonfatal MI if they have ischemic events with continuous ST-segment monitoring that are unrecognized clinically. In this small cohort with unrecognized ischemia, the initial body surface potential maps estimated from optimal ischemia electrode sites did not improve on 12-lead ST-segment monitoring to identify this high-risk group.

Postprocedural single-lead ST-segment deviation and long-term mortality in patients with ST-segment elevation myocardial infarction treated by primary angioplasty

Objective:To evaluate the prognostic role of postprocedural single-lead residual ST-segment deviation for electrocardiographic evaluation of myocardial perfusion in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary angioplasty.Design:Prospective observational...

Novel electrocardiogram configurations and transmission procedures in the prehospital setting: effect on ischemia and arrhythmia determination

Aim The aims of this report are to (1) describe a novel prehospital 12-lead electrocardiogram (ECG) configuration and transmission procedure used in the Synthesized Twelve-lead ST Monitoring and Real-time Tele-electrocardiography Study and to (2) report on the frequency of arrhythmias in field ECGs compared with the first hospital ECG. Methods The Synthesized Twelve-lead ST Monitoring and Real-time Tele-electrocardiography Study is a 5-year randomized clinical trial ending in 2008. All emergency vehicles responding to 911 calls in Santa Cruz County, Calif, have been equipped with portable monitor defibrillators with a special study software that (1) synthesizes a 12-lead ECG from 5 electrodes, (2) measures ST amplitudes in all 12 leads every 30 seconds, and (3) automatically transmits an ECG to the target emergency department if there is a change in ST amplitude of 200 μV in 1 lead or more or 100 μV in 2 contiguous leads or more lasting 2.5 minutes. An initial ECG is transmitted by paramedics, which activates the software. Subsequent transmissions of ST event ECGs occur automatically without paramedic decision making. Results Prehospital ECGs had a greater frequency of arrhythmias than the first hospital ECG in the group as a whole (n = 433; 33.3% vs 28.9%; P ≤ .001), as well as the subgroup with acute coronary syndrome (n = 185; 30.3% vs 26.5%; P ≤ .001). More tachyarrhythmias occurred in the field and slightly more bradyarrhythmias occurred at the time of the first hospital ECG. Conclusions Prehospital continuous 12-lead ST-segment ischemia monitoring with computer-assisted automatic mobile telephone transmission of ST event ECGs to the target hospital is feasible. More arrhythmias occur in the prehospital phase than are evident on the first hospital ECG.

Association of sustained ventricular arrhythmias with transient myocardial ischemia in patients hospitalized with acute coronary syndrome

Background: Myocardial ischemia is a known substrate for the development of malignant ventricular arrhythmias. Purpose: The purpose of this secondary analysis was to determine the occurrence of ventricular arrhythmias at the time of transient myocardial ischemia in patients hospitalized with acute coronary syndrome (ACS). Methods: Patients who presented to the emergency department at the San Francisco Medical Center, University of California, San Francisco, Calif, with chest pain or anginal equivalent were enrolled in a prospective study involving 12-lead electrocardiogram Holter ST-segment monitoring. Transient myocardial ischemia was defined as a change in ST-segment amplitude of 200 lV or greater in 1 lead or more or 100 lV or greater in 2 leads or more, lasting for at least 60 seconds. An associated arrhythmia was defined as sustained ventricular tachycardia (VT) or ventricular fibrillation during or 10 minutes before or after an ST event. Results: One thousand one hundred thirty-six (emergency department) patients evaluated for chest pain/anginal equivalent were monitored for 24 hours. Of these, 270 patients were hospitalized with a diagnosis of ACS (acute myocardial infarction, n = 95; unstable angina, n = 175). Of the 270 patients, 31 (11%) had a total of 44 STevents (number, 1.4F 1.6; range, 1-10; duration, 27 F 15 minutes). Of the 44 ST events, 24 (55%) had an isolated premature ventricular contraction or ventricular couplet; however, none had associated sustained VT/ventricular fibrillation. The figure below shows the longest sustained arrhythmia (9-beat VT) among the 31 patients, and it occurred in the absence of electrocardiogram signs of ischemia. Conclusions:With current medical management, frequency of ischemia is low in patients hospitalized with ACS, and malignant ventricular arrhythmias were not observed in this cohort.

Designing prehospital ECG systems for acute coronary syndromes. Lessons learned from clinical trials involving 12-lead ST-segment monitoring

Background Clinical trials in prehospital electrocardiography have focused primarily on ST elevation myocardial infarction (STEMI). The aims of this study were to determine, in patients presenting to the emergency department with acute coronary syndrome (ACS), the (1) relative frequency of various ACS types and (2) sensitivity of conventional ST-T criteria for diagnosing ischemia in non-STEMI or unstable angina. Methods A secondary analysis was conducted using data from prospective trials involving 12-lead ST monitoring. Results Of 968 patients with ACS, 120 (12%) were STEMI, 289 (30%) were non-STEMI, and 559 (58%) were unstable angina. Conventional electrocardiogram (ECG) criteria were insensitive (sensitivity, 20%) for detecting ischemia in patients with non-STEMI or unstable angina. There was no ischemia on the initial ECG in 85 patients who had subsequent events with ST monitoring. Conclusion Non-STEMI and unstable angina are the most prevalent types of ACS. The initial ECG is insensitive for detecting ischemia in this population. Transient myocardial ischemia detected with ST monitoring commonly occurs in patients without ischemia on the initial ECG. ST monitoring should be considered in designing prehospital ECG systems.

Utilization of ST-Segment Deviation Sum and Change Score to Identify High Risk Emergency Department Chest Pain Patient with Acute Coronary Syndromes

Background: No information is currently available regarding optimal cutoff values of the ST-segment deviation sum (STDsum) score for predicting acute myocardial infarction (AMI) and ST-segment deviation change (STDchange) score for predicting adverse outcome (AO) in emergency department (ED) chest pain patients undergoing continuous 12-lead ST-segment monitoring.

Cardiac Troponin After Major Vascular Surgery: The Role of Perioperative Ischemia, Preoperative Thallium Scanning, and Coronary Revascularization

We sought to determine the role of preoperative predictors, particularly ischemia, on preoperative thallium scanning (PTS) and coronary revascularization on low-level and conventional troponin elevations after major vascular surgery. Postoperative cardiac troponin (cTn) elevations have recently been shown to predict both short- and long-term mortality after vascular surgery. The perioperative data, including PTS and subsequent coronary revascularization, continuous perioperative 12-lead ST-segment trend monitoring, cTn-I and/or cTn-T, and creatine kinase-MB fraction in the first three postoperative days, were prospectively collected in 501 consecutive elective major vascular procedures. Moderate to severe inducible ischemia on PTS was associated with a 49.0% incidence of low-level (cTn-I >0.6 and/or cTn-T >0.03 ng/ml) and 22.4% conventional (cTn-I >1.5 and/or cTn-T >0.1 ng/ml) troponin elevation. In contrast, patients with preoperative coronary revascularization had 23.4% and 6.4% low-level and conventional troponin elevations, respectively, similar to patients without ischemia on PTS. By multivariate logistic regression, ischemia on PTS was the most important predictor of both low-level and conventional troponin elevations (adjusted odds ratios [ORs] 2.5 and 2.7, p = 0.02 and 0.04, respectively), whereas preoperative coronary revascularization predicted less troponin elevations (adjusted ORs 0.35 and 0.16, p = 0.045 and 0.022, respectively). Postoperative ischemia (>10 min), the more so prolonged (>30 min) ischemia was the only independent predictor of troponin elevation if added with the preoperative predictors to the multivariate analysis (ORs 15.8 and 22.8, respectively, p < 0.001). Troponin elevations occur frequently after vascular surgery. They are strongly associated with postoperative ischemia, predicted by inducible ischemia on PTS, and reduced by preoperative coronary revascularization.

Combining baseline clinical descriptors and real-time response to therapy: the incremental prognostic value of continuous ST-segment monitoring in acute myocardial infarction

Background Clinical descriptors and ST-segment recovery variables hold prognostic information for clinical outcome after thrombolysis for acute myocardial infarction (MI). We sought to define the incremental prognostic value of continuous 12-lead ST-segment monitoring variables to clinical risk descriptors identified by the Global Utilization of Streptokinase and TPA (alteplase) for Occluded Coronary Arteries (GUSTO-I) trial 30-day mortality analysis. Methods Of 1,777 patients enrolled in continuous ST-segment substudies from the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI-9), GUSTO-I, Duke University Clinical Cardiology Study (DUCCS-II), Integrilin to manage Platelet Aggregation to Combat Thrombus in Acute Myocardial Infarction (IMPACT-AMI), Promotion of Reperfusion by Inhibition of Thrombin During Myocardial Infarction Evolution (PRIME), and Platelet Aggregation Receptor Antagonist Dose Investigation and Reperfusion Gain in Myocardial Infarction (PARADIGM) trials, 825 patients qualified for assessment of time to recovery. ST recovery variables analyzed were time to stable ST-recovery and late ST elevation. Patients who were at low clinical risk (n = 261) had no high-risk descriptors, and patients at high clinical risk (n = 564) had at least 1 of these high-risk descriptors: age ≥70 years, systolic blood pressure ≤110 mm Hg, heart rate ≥90 beats/min, anterior MI, or previous MI. High (n = 90), moderate (n = 318), and low (n =417) ST-risk groups were defined by the presence of both slow ST recovery and late ST elevation, one or the other, or neither, respectively. End points analyzed were inhospital death and combined death, reinfarction, or congestive heart failure. Results There was a trend toward increased mortality rate in the high-clinical/high-ST-risk group. For the composite end point, ST subgrouping resulted in significant event stratification in both patients at low and high clinical risk. In multivariable analysis, age and heart rate were independent predictors of both mortality and the composite end point. Late ST elevation added incremental prognostic information. Conclusion Age, heart rate, and late ST elevation are powerful, independent predictors of adverse clinical outcome. Continuous monitoring allows noninvasive assessment of the response to therapy. Consequently, this technique will enhance the potential to risk-stratify individual patients in a real-time setting.

Early Definition of Treatment Outcomes After Reperfusion Therapy for Myocardial Infarction

Aims. Early definition of treatment outcomes, including coronary patency and infarct size, after reperfusion therapy for myocardial infarction (MI) is desirable to identify patients requiring further intervention. Methods and Results. Patients receiving reperfusion therapy for a first MI had continuous 12-lead ST segment monitoring to document reperfusion and ischaemia time. Infarct size was measured by 12-lead QRS score and radionuclide scintigraphy ( 201 Tl single-photon emission computed tomography, SPECT) at 1 week, and left ventricular function by echocardiography at 1 week and 1 month. Resolution of ST elevation accurately detected TIMI 2 or 3 reperfusion (predictive accuracy 93%) in 55 patients undergoing immediate angioplasty, but ST recovery was delayed (17±14 min) after angiographic reperfusion. A multivariate model, including risk region and ischaemia time, accurately predicted MI size ( R 2=0.80, P<0.00001) in these patients. The same model, prospectively applied on Day 1 to 154 patients receiving thrombolytic therapy, accurately predicted MI size, measured by QRS score ( R 2=0.88, P<0.0000001) and 201 Tl SPECT ( R 2=0.75, P<0.000001) at 1 week for individual patients. Regional myocardial wall motion at 1 month was directly correlated with MI size predicted by the model on Day 1 ( r=0.73, P<0.0001). Conclusions. Use of ST segment monitoring during reperfusion therapy facilitates early prediction of treatment outcomes, including coronary reperfusion, infarct size and ventricular function.

1003-93 Outcomes prediction with continuous 12-lead ST-segment recovery in ST elevation myocardial infarction: Similarities or differences with thrombolytic versus direct stenting populations?

1003-93 Outcomes prediction with continuous 12-lead ST-segment recovery in ST elevation myocardial infarction: Similarities or differences with thrombolytic versus direct stenting populations?

Improved speed and stability of st-segment recovery with reduced-dose tenecteplase and eptifibatide compared with full-dose tenecteplase for acute st-segment elevation myocardial infarction

ObjectivesThis sub-study of the Integrilin and Tenecteplase in Acute Myocardial Infarction (INTEGRITI) trial evaluated of the impact of combination reperfusion therapy with reduced-dose tenecteplase plus eptifibatide on continuous ST-segment recovery and angiographic results. BackgroundCombination therapy with reduced-dose fibrinolytics and glycoprotein IIb/IIIa inhibitors for ST-segment elevation myocardial infarction improves biomarkers of reperfusion success but has not reduced mortality when compared with full-dose fibrinolytics. MethodsWe evaluated 140 patients enrolled in the INTEGRITI trial with 24-h continuous 12-lead ST-segment monitoring and angiography at 60 min. The dose-combination regimen of 50% of standard-dose tenecteplase (0.27 μg/kg) plus high-dose eptifibatide (2 boluses of 180 μg/kg separated by 10 min, 2.0 μg/kg/min infusion) was compared with full-dose tenecteplase (0.53 μg/kg). ResultsThe dose-confirmation regimen of reduced-dose tenecteplase plus high-dose eptifibatide was associated with a faster median time to stable ST-segment recovery (55 vs. 98 min, p = 0.06), improved stable ST-segment recovery by 2 h (89.6% vs. 67.7%, p = 0.02), and less recurrent ischemia (34.0% vs. 57.1%, p = 0.05) when compared with full-dose tenecteplase. Continuously updated ST-segment recovery analyses demonstrated a modest trend toward greater ST-segment recovery at 30 min (57.7% vs. 40.6%, p = 0.13) and 60 min (82.7% vs. 65.6%, p = 0.08) with this regimen. These findings correlated with improved angiographic results at 60 min. ConclusionsCombination therapy with reduced-dose tenecteplase and eptifibatide leads to faster, more stable ST-segment recovery and improved angiographic flow patterns, compared with full-dose tenecteplase. These findings question the relationship between biomarkers of reperfusion success and clinical outcomes.

Body surface potential mapping improves detection of ST segment alteration during percutaneous coronary intervention

Background: The 12-lead electrocardiogram underestimates ST segment alteration in acute coronary syndromes compared with multi-lead body surface mapping. We assessed whether 80-lead mapping would improve detection of ST alteration during percutaneous coronary intervention. Methods: Simultaneous maps and 12-lead electrocardiograms were recorded pre-procedure, during balloon inflation and post-procedure from patients undergoing elective intervention to native coronary arteries. Recordings were obtained from 39 inflations (19 patients). All arteries were successfully stented. Results: Mean ‘lead specific’ ST alteration (the difference in ST elevation/depression between pre-procedure and inflation recordings in the lead showing maximal ST alteration) was greater on the map than on electrocardiogram, both for ST elevation (0.16±0.02 vs. 0.06±0.01 mV; p<0.001) and ST depression (0.11±0.017 vs. −0.03±0.006 mV; p<0.001). During first inflations (n=19), mean lead specific ST elevation and depression on map were greater than on electrocardiogram (0.20±0.034 vs. 0.07±0.015 mV; p<0.001 and 0.11±0.029 vs. 0.03±0.009 mV; p=0.001, respectively). Mapping detected greater summated ST elevation and depression during inflation than electrocardiogram (0.04±0.005 vs. 0.021±0.003 mV; p<0.001 and 0.026±0.004 vs. 0.011±0.002 mV; p<0.001, respectively). Qualitative analysis of maps and electrocardiograms showed that 21/39 (53.8%) maps recorded during inflation met criteria for myocardial ischaemia compared with 7/39 (17.9%) electrocardiograms (p<0.001). Conclusion: Body surface mapping compared with the 12-lead electrocardiogram improves detection of myocardial ischaemia during intervention.