Mechanical compression devices for cardiac arrest: report of three cases.

Mechanical compression devices enable transportation of patients with cardiac arrest to the catheterization laboratory. Coronary angiography and coronary interventions can be performed while the patients are being resuscitated with these devices. In this report, we describe three cases in whom resuscitation with mechanical compression devices and rapid transportation to the catheterization laboratory resulted in favorable cardiac and neurological outcome.

Long-term clinical outcomes, health-related quality of life, and costs in different treatment modalities of stable coronary artery disease.

Aims: This study is a prospective, observational 8-year follow-up of 300 stable unselected coronary artery disease patients entering elective coronary angiography in 2002-03. Recorded were clinical outcomes, health-related quality of life (HRQoL), and secondary care costs after coronary artery bypass graft (CABG) surgery, percutaneous coronary intervention (PCI), or medical therapy (MT). Methods and results: HRQoL was measured by the 15D instrument at baseline, 6 months, and 8 years. Regression techniques with an adjustment for relevant baseline characteristics were used to compare the 8-year survival and change in HRQoL between the groups. At baseline, all groups had statistically significantly impaired HRQoL compared with age- and gender-standardized general population. Six months after invasive interventions the mean HRQoL score had improved in a statistically significant and clinically important manner. This improvement was maintained at 8 years as the HRQoL no longer differed from that of the general population, whereas MT patients were still worse off. However, after adjustment for baseline characteristics, the groups no longer differed regarding 8-year survival or change in HRQoL among survivors. Mean 8-year secondary care costs were without (with) adjustment for baseline characteristics: €17 498 (16 730) for CABG, €7245 (6920) for PCI, and €4514 (4580) for MT, respectively. Conclusion: When adjusted for baseline characteristics, no statistically significant differences were found between the patient groups in 8-year survival or change in HRQoL among survivors. The 8-year mean secondary care costs of CABG were over two-fold and almost four-fold, even after adjustment for baseline characteristics, compared with those of PCI and MT.

Safety of the primary percutaneous coronary intervention strategy combining pre-hospital prasugrel, enoxaparin and in-hospital bivalirudin in acute ST-segment elevation myocardial infarction.

BACKROUND: The optimal antithrombotic treatment during a primary percutaneous coronary intervention (pPCI) is not known. This single center registry study aims to assess the safety of a novel antithrombotic regimen combining enoxaparine and prasugrel at presentation, followed by bivalirudin at the catheterisation laboratory. METHODS: All consecutive patients who underwent a pPCI were collected prospectively. The primary endpoint was major bleeding within 30 days. The secondary endpoints were a composite of major adverse cardiovascular events (MACE) consisting of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, a new target vessel revascularisation and all-cause mortality at 30 days. RESULTS: Ninety-nine out of the total of 390 patients were treated according to the new regimen (protocol-treated group). The rest received other antithrombotic treatment (non-protocol-treated group). The protocol-treated group had a lower risk than the non-protocol-treated group according to the GRACE ischaemic (112 vs. 124, p = 0.002) and CRUSADE bleeding scores (21 vs. 28, p < 0.0001). The incidences of bleeding were similar: severe GUSTO or TIMI bleeding occurred in 0 % of the protocol-treated group and in 1.0 and 0.3 %, respectively, of the other group (p = 0.311 for GUSTO and p = 0.559 for TIMI). The incidence of MACE in the groups was 6.1 and 10.7 %, respectively (p = 0.178). The respective incidences of all-cause mortality were 5.1 and 9.6 % (p = 0.158). CONCLUSIONS: Administration of the novel antithrombotic regimen seems to be safe.

[The use of direct oral anticoagulants (DOAC) in the treatment atrial fibrillation (AF) patients]. / Suorien antikoagulanttien käyttö eteisvärinässä.

AF is associated with the risk of stroke, and this risk is exceedingly high in elderly patients (> or = 75 years) and in patients after a stroke. DOACs are appropriate anticoagulants for AF patients without mechanical heart valves or mitral stenosis. Patients on DOACs do not require routine monitoring of coagulation, but need regular follow-up visits including an assessment of therapy adherence, thromboembolic and bleeding events and measurements of hemoglobin and platelets values as well as renal and liver function.

Trends in treatment delays for patients with acute ST-elevation myocardial infarction treated with primary percutaneous coronary intervention.

BACKGROUND: Treatment delay is an important prognostic factor for patients with acute ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). We aimed to determine recent trends in these delays and factors associated with longer delays. METHODS: We compared two datasets collected in Helsinki University Central Hospital in 2007-2008 (HUS-STEMI I) and 2011-2012 (HUS-STEMI II), a total of 500 patients treated with primary PCI within 12 hours of the onset of symptoms. RESULTS: Delays of the emergency medical system (EMS) were longer in HUS-STEMI I than II (medians 81 vs. 67 min, respectively, p < 0.001). Although door-to-balloon times were longer in the later dataset (33 vs. 48 min, p < 0.001) most of the patients (75.3% vs. 62.8%, respectively, p = 0.010) were treated within the recommendation (<60 min) of the European Society of Cardiology (ESC). In HUS-STEMI II, patient arrival at the hospital during off-hours was associated with longer door-to-balloon time (40 and 57.5 min, p = 0.001) and system delay (111 and 127 min, p = 0.009). However, in HUS-STEMI I, arrival time did not impact the delays. Longer system delay was associated with higher mortality rates. CONCLUSIONS: Though the delays inside the hospital have increased they are still mostly within the ESC guidelines. Still, only about half of the patients are treated within a system delay of recommended two hours. Albeit our results are good in comparison with previous studies, further efforts for decreasing the delays particularly within the EMS should be established.

Ultra-acute increase in blood glucose during prehospital phase is associated with worse short-term and long-term survival in ST-elevation myocardial infarction.

BACKGROUND: The current study was to investigate the blood glucose changes in ultra-acute phase in patients with ST-elevation myocardial infarction (STEMI) and its associations with patient outcome. METHODS: This study was a retrospective population-based observational study utilizing prospectively collected registry data complemented with laboratory data. All adult patients with STEMI treated by emergency medical services (EMS) in the city of Helsinki from January 2006 to December 2010 were included in the study. Both prehospital and hospital admission glucose values were available from 152 (32%) of all STEMI patients (n = 469). RESULTS: Change in blood glucose from prehospital phase to emergency department admission was significantly higher in non-survivors within 30 days compared to survivors (+1.2 ± 5.1 vs. -0.3 ± 2.4 mmol/l [mean ± SD], P = 0.03). Furthermore, the 3-year survival rate was significantly lower in patients with an evident (≥2 mmol/l) rise in blood glucose (P = 0.02). In patients with impaired left ventricle function (best ejection fraction < 40%), blood glucose increased more compared to patients without it (1.2 ± 2.9 vs. 0.4 ± 2.7 mmol/l, P = 0.01). Increase in glucose was correlated with peak myocardial creatinine kinase (r = 0.17, P = 0.04) as a marker of increased size of infarct, but not with glycosylated haemoglobin A1C as a marker of chronic hyperglycaemia (r = -0.12, P = 0.27). CONCLUSIONS: In patients with STEMI, ultra-acute hyperglycaemia during prehospital phase is associated with increased mortality, impaired cardiac function and increased size of infarct.

Postresuscitation hemodynamics during therapeutic hypothermia after out-of-hospital cardiac arrest with ventricular fibrillation: a retrospective study.

AIMS OF THE STUDY: To evaluate the incidence of postresuscitation myocardial depression (PRMD) and hemodynamical parameters associated with PRMD in patients treated with therapeutic hypothermia (TH) after out-of-hospital cardiac arrest with ventricular fibrillation (OHCA-VF). METHODS: Analysis of hemodynamical data from computerized clinical databases of two academic ICUs during two year period. We analyzed hemodynamical data from a subgroup of patients with pulmonary artery catheter (PAC). We defined PRMD as a cardiac index (CI) less than 1.5l/(minm(2)) any time during the first 12h and compared clinical variables and hemodynamical parameters in patients with or without PRMD. RESULTS: Of 120 included patients PAC monitoring was used in 47 (39%). Of 47, 31 (66%, 95% CI 52% to 80%) developed PRMD. There was no difference in urinary output, lactate, mean arterial or central venous pressures or mixed venous saturation between patients with or without PRMD. Low CI was reversed with dobutamine infusion. Presence or absence PRMD was not associated with 6-month neurological outcome. CONCLUSION: Two-thirds of the OHCA-VF patients develops transient postresuscitation myocardial depression not easily detected without monitoring of CI during therapeutic hypothermia. Further controlled studies are warranted to evaluate the value of different hemodynamic targets and monitoring after cardiac arrest in terms of outcome.

U wave features in body surface potential mapping in post-myocardial infarction patients.

BACKGROUND: The data on U wave features in post-myocardial infarction (MI) remain sparse. We employed 120-lead body surface potential mapping (BSPM) to explore the U wave in patients with remote MI. METHODS: Sixty post-MI patients and 46 healthy controls were examined. After signal averaging, the polarity changes of U wave related to the T wave were analyzed, and the spatial and temporal U wave parameters were computed. RESULTS: Four types of patterns based on T and U polarity were recognized. A pattern with positive T and U waves was related to better ventricular function. The study groups did not differ as regards to Tend-Uapex and Tapex-Uapex intervals whereas Uapex-Uend was significantly longer in MI patients (110 ± 20 ms vs. 100 ± 13 ms, P = 0.004). MI patients had significantly higher U wave maximum amplitude (70 ± 30 µV vs. 50 ± 20 µV, P < 0.001), and U integral area (3.96 ± 1.50 µV·s vs. 3.17 ± 0.99 µV·s, P = 0.002), but lower corresponding T wave parameter values, thus resulting into higher U/T maximum amplitude and area ratios (0.16 ± 0.10 vs. 0.09 ± 0.04, P < 0.001; and 0.13 ± 0.06 vs. 0.09 ± 0.03, P < 0.001). In comparison to 12-lead ECG, BSPM covering the entire thorax enhanced the detection of U waves. CONCLUSION: MI tends to increase the U amplitude and prolong the later part of U wave duration thus augmenting the U wave. The size and location of infarction were associated with specific T and U wave polarity patterns.

Outcome up to one year following different reperfusion strategies in acute ST-segment elevation myocardial infarction: the Helsinki-Uusimaa Hospital District registry of ST-Elevation Acute Myocardial Infarction (HUS-STEMI).

AIMS: Current guidelines prefer primary percutaneous coronary intervention (pPCI) over fibrinolysis in the treatment of acute ST-elevation myocardial infarction (STEMI). Pre-hospital fibrinolysis followed by early invasive evaluation is an alternative that we have used in patients presenting within three hours of symptom onset. We made a survey of patients suffering an acute STEMI over one year to assess mortality and adverse events following either pPCI or fibrinolysis. METHODS AND RESULTS: Of the 448 consecutive STEMI patients, 194 were treated with pPCI and 176 underwent fibrinolysis; 78 patients received no reperfusion treatment within 12 hours (NRT group). The median TIMI risk scores were 4.0, 3.0 and 4.0 in the pPCI, fibrinolysis and NRT groups, respectively (p<0.001). Mortality at one year was 14.4% following pPCI, 5.1% following fibrinolysis and 12.8% in the NRT group (p=0.011 across all groups and p=0.003 between pPCI and fibrinolysis, adjusted for differences in risk factors). The one-year composite of cardiovascular death, stroke, reinfarction and new revascularization was 20.1%, 18.2% and 26.9% for the pPCI, fibrinolysis and NRT groups, respectively (p=NS). In patients presenting within three hours of symptom onset, one-year mortality was 3.7% in the fibrinolysis group (n=163) and 15.3% in the pPCI group (n=118) (adjusted p =0.001), while the composite of adverse events was 16.6% in the former group and 19.5% in the latter (p=NS). CONCLUSION: Pre-hospital fibrinolysis followed by routine early invasive evaluation provides an excellent reperfusion strategy for low-risk STEMI patients presenting early after symptom onset.

Proinflammatory HLA-DRB1*01-haplotype predisposes to ST-elevation myocardial infarction.

BACKGROUND: Major histocompatibility complex (MHC) gene region harbours haplotypes that associate with coronary artery disease (CAD). Their role in ST-elevation infarction (STEMI) or on the inflammatory level is not known. METHODS: Four candidate MHC markers were analyzed by real-time quantitative PCR and constructed into haplotypes from patients with STEMI (n = 162), matched controls with no CAD (n = 319) and general population sample (n = 149). High sensitivity C-reactive protein (hsCRP) was assessed in a follow-up visit from patients (n = 86) and at inclusion from other study subjects. RESULTS: The haplotype with one copy of HLA-DRB1*01, C4A, C4B but no HLA-B*35 doubled the risk of STEMI (OR = 2.15, 95%CI = 1.11-4.15, p = 0.020 for patients vs. controls, and OR = 2.26, 95%CI = 0.97-5.24, p = 0.052 for patients vs. population sample). The association between patients and controls persisted in multivariate analyses. The frequency of the haplotype was 5.86% (n = 19/324) in patients, 2.82% (n = 18/638) in controls and 2.68% (n = 8/298) in population sample. None of the individual MHC markers alone showed significant association with STEMI. In multivariate analyses, the haplotype carriers had higher hsCRP levels in patients (median 3.37 mg/L in carriers vs. 1.14 mg/L in non-carriers, p = 0.019) and in controls (median 2.90 mg/L vs. 1.21 mg/L, p = 0.009, respectively). CONCLUSION: The MHC haplotype associates with STEMI and elevated baseline hsCRP levels. The results are in concordance with previous data on non-STEMI patients, implying that a HLA-DRB1*01--related haplotype increases the risk of CAD, possibly though increased inflammation.

Analysing current trends in care of acute myocardial infarction using PERFECT data.

INTRODUCTION: This article in the supplement issue on the Performance, Effectiveness, and Costs of Treatment episodes (PERFECT)-project describes the PERFECT AMI (acute myocardial infarction) Database, which is developed to measure the performance of hospitals and hospital districts in Finland. We analyse annual trends and regional differences in performance indicators and whether the utilisation of services and costs of hospital care are related to improvement in survival of AMI patients. MATERIAL AND METHODS: The study population consists of ten annual cohorts (1998-2007) of patients hospitalised for AMI. RESULTS: Since 1998 the treatment pattern has changed rather radically, the utilisation rate of percutaneous coronary intervention (PCI) has increased and coronary procedures have been performed earlier after myocardial infarction. Outcome measured by various measures of mortality has improved considerably. However, trends in the development of the use of services and outcomes are not similar between hospital districts. An increase in cost was positively and statistically significantly related to decrease in mortality, but the effect was not very strong. CONCLUSION: There is potential for decreased mortality from actions that do not increase the costs and for enhancing performance in the regions and hospitals with poor performance.

[Cardiogenic shock--severe complication of myocardial infarction]. / Kardiogeeninen sokki--sydäninfarktin vakava komplikaatio.

Cardiogenic shock is the most common fatal complication of acute myocardial infarction. The conception of an extensive irreparable myocardial injury underlying the cardiogenic shock has changed especially with the results of the SHOCK study. In addition to the infarction injury, an acute inflammatory reaction, neurohumoral activation as well as improving myocardial stunning influence the development of shock. Mortality is high at the initial stage, whereas subsequent prognosis is equivalent to that seen in other infarction patients. Essential therapy consists in a prompt revascularization of the infarcted area and optimization of hemodynamics, if necessary by applying mechanical supportive therapies.

Fragmented QRS in prediction of cardiac deaths and heart failure hospitalizations after myocardial infarction.

BACKGROUND: Increased QRS fragmentation in visual inspection of 12-lead ECG has shown association with cardiac events in postmyocardial infarction (MI) patients. We investigated user-independent computerized intra-QRS fragmentation analysis in prediction of cardiac deaths and heart failure (HF) hospitalizations after MI. METHODS: Patients (n = 158) with recent MI and reduced left ventricular ejection fraction (LVEF) were studied. A 120-lead body surface potential mapping was performed at hospital discharge. Intra-QRS fragmentation was computed as the number of extrema (fragmentation index FI) in QRS. QRS duration (QRSd) was computed for comparison. RESULTS: During a mean follow-up of 50 months 15 patients suffered cardiac death and 23 were hospitalized for HF. Using the mean + 1 SD as cut-point both parameters were univariate predictors of both end-points. In multivariate analysis including age, gender, LVEF, previous MI, bundle branch block, atrial fibrillation, and diabetes FI was an independent predictor for cardiac deaths (HR 8.7, CI 3.0-25.6) and HF hospitalizations (HR 3.8, CI 1.6-9.3) whereas QRSd only predicted HF hospitalizations (HR 4.6, CI 2.0-10.7). In comparison to QRSd, FI showed better positive (PPA) and equal negative (NPA) predictive accuracy for both end-points, and PPA was further improved when combined to LVEF < 40%. Limiting fragmentation analysis to 12-lead ECG or a randomly selected 8-lead set instead of all 120 leads resulted in an almost similar prediction. CONCLUSIONS: Increased QRS fragmentation in post-MI patients predicts cardiac deaths and HF progression. A computer-based fragmentation analysis is a stronger predictor than QRSd.

Drug-eluting stents in acute myocardial infarction: updated meta-analysis of randomized trials.

BACKGROUND: Use of drug-eluting stents in patients with acute myocardial infarction (AMI) remains an "off label" indication due to concerns regarding their performance in this patient subset. METHODS: We searched Medline, the Cochrane Central Register of Controlled Trials, and Internet-based sources of information on clinical trials in cardiology for randomized trials comparing drug-eluting stents with bare-metal stents in patients with AMI. Hazard ratios for the composite of death or recurrent myocardial infarction, (primary safety endpoint), reintervention (primary efficacy endpoint), death, recurrent myocardial infarction, and stent thrombosis were calculated performing a meta-analysis of 14 randomized trials with 7,781 patients. RESULTS: There was no difference in the hazard of death or recurrent myocardial infarction (hazard ratio, 0.91; [95% CI 0.75-1.09]) between patients treated with drug-eluting stents versus patients treated with bare-metal stents. Treatment with drug-eluting stents resulted in a significant reduction in the hazard of reintervention (0.41 [95% CI 0.32-0.52]). The hazards of death (0.90 [95% CI 0.71-1.15]), myocardial infarction (0.81 [95% CI 0.63-1.04]), and stent thrombosis (0.84 [95% CI 0.61-1.17]) were not significantly different between patients treated with drug-eluting stents versus patients treated with bare-metal stents. CONCLUSIONS: Use of drug-eluting stents in patients with AMI is safe and markedly reduces the need for reintervention as compared to bare-metal stents.

Early abciximab administration before primary percutaneous coronary intervention improves clinical outcome in elderly patients transferred with ST-elevation myocardial infarction: data from the EUROTRANSFER registry.

BACKGROUND: Limited data are available concerning benefits and risks of early abciximab (EA) administration before primary percutaneous coronary intervention (PPCI) in elderly ST-segment elevation myocardial infarction (STEMI) patients. The objective of the study was to assess the impact of EA before PPCI in elderly (>or=65 years) patients. METHODS AND RESULTS: We identified 545 patients <65 years (354 with EA administration (>30 min before PPCI), 191 late abciximab (LA)), and 541 patients >or=65 years of age (373 EA, 168 LA) in the EUROTRANSFER Registry database. Elderly patients were more likely to have comorbidities, angiographic PCI complications, and bleeding events. EA promotes infarct-related artery patency before PPCI and improves myocardial reperfusion after PPCI in both age groups, but the risk of 30-day death (EA vs. LA: <65 years, 2.0% vs. 1.6%; p=0.999; >or=65 years, 5.9% vs. 14.3%; p=0.001) and 30-day death+reinfarction (EA vs. LA: <65 years, 2.5% vs. 2.1%; p=0.999; >or=65 years, 7.5% vs. 17.3%; p=0.001) was reduced in elderly patients only. There was no difference in bleedings, especially major bleedings requiring transfusion (EA vs. LA: patients <65 years, 2.3% vs. 0%, p=0.055; >or=65 years, 2.4% vs. 3%; p=0.448) between groups. CONCLUSIONS: Patients >or=65 years of age have a substantially increased risk of angiographic PCI complications, death and bleeding events compared with their younger counterparts. Strategy of EA before PPCI improves reperfusion parameters and clinical outcome in elderly patients and is not associated with elevated risk of major bleeding.

Drug-eluting stents versus bare-metal stents in diabetic patients with ST-segment elevation acute myocardial infarction: a pooled analysis of individual patient data from seven randomized trials.

INTRODUCTION AND OBJECTIVES: The performance of drug-eluting stents (DESs) in high-risk patients with diabetes and acute ST-elevation myocardial infarction (STEMI) who have undergone primary angioplasty has not been previously studied. The objective was to evaluate the efficacy and safety of DESs in diabetic patients with STEMI. METHODS: We performed a pooled analysis of individual patient data from seven randomized trials that compared DESs (i.e., sirolimus- or paclitaxel-eluting stents) with bare-metal stents (BMSs) in patients with STEMI. The analysis involved 389 patients with diabetes mellitus from a total of 2476 patients. The outcomes of interest were target-lesion revascularization, stent thrombosis, death and the composite endpoint of death or recurrent myocardial infarction during a follow-up of 12-24 months. RESULTS: Overall, 206 diabetic patients received a DES and 183, a BMS. The risk of target-lesion revascularization was significantly lower in patients treated with a DES compared to those treated with a BMS (hazard ratio [HR] 0.44, 95% confidence interval [CI] 0.23-0.88; P=.02). There was no significant difference in the risk of stent thrombosis between those treated with a DES or a BMS (HR 0.33, 95% CI 0.09-1.13; P=.08). Similarly, the risk of the combined endpoint of death or myocardial infarction was not significantly different between patients treated with a DES or a BMS (HR 0.64, 95% CI 0.36-1.13; P=.12). CONCLUSIONS: Compared with BMSs, DES use improved clinical outcomes in diabetic patients undergoing primary angioplasty for STEMI: the need for reintervention was reduced, with no increase in mortality or myocardial infarction.

Complex T-wave morphology in body surface potential mapping in prediction of arrhythmic events in patients with acute myocardial infarction and cardiac dysfunction.

AIMS: Heterogeneous ventricular repolarization is associated with sudden cardiac death after myocardial infarction (MI). This prospective study investigated repolarization disparity with parameters based on T-wave morphology in body surface potential mapping (BSPM) in the assessment of arrhythmia risk in patients with a recent MI and cardiac dysfunction. METHODS AND RESULTS: Patients (n = 158) had 120-lead BSPM and 12-lead electrocardiogram (ECG) registered soon after acute MI. Principal component analysis (PCA) of the T-wave and T-wave vector loop descriptors were applied to compute parameters describing T-wave morphology and its variation. The study endpoints were arrhythmic events and all-cause mortality. During a mean follow-up of 50 months, 30 patients (19%) died and 16 (10%) had an arrhythmic event. Most of the parameters differed significantly between patients with and without arrhythmic events. In univariate analysis, T-wave vector loop length (TLL) and PCA parameter PCA(3) in BSPM and TLL in ECG were significant predictors of arrhythmic events. In multivariate analysis including several clinical variables, these parameters also showed an independent prediction, with parameters in BSPM performing somewhat better. None of the parameters predicted all-cause mortality. CONCLUSION: Complex T-wave morphology in BSPM is a marker of arrhythmia propensity in patients with a recent MI and cardiac dysfunction.

Predicting the culprit artery in acute ST-elevation myocardial infarction and introducing a new algorithm to predict infarct-related artery in inferior ST-elevation myocardial infarction: correlation with coronary anatomy in the HAAMU Trial.

AIMS: The objective of this study is to predict the culprit artery from the electrocardiogram (ECG) by predefined criteria and to compare a new algorithm with a previous one for predicting the culprit artery in inferior ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: In "all-comers" (n = 187) with acute STEMI, with ECG and angiography from the acute phase, the positive and negative predictive values for the prediction of the left anterior descending coronary artery, left circumflex coronary artery, or right coronary artery as the infarct-related artery were 96% and 96%, 65% and 95%, 92% and 97%, respectively. In inferior STEMI (n = 98), positive and negative predictive values to predict the right coronary artery or the left circumflex coronary artery as the culprit artery were 92% and 75% and 75% and 94%, respectively. CONCLUSIONS: In "all-comers" with STEMI, the culprit artery could be predicted by ECG criteria with high predictive values. In inferior STEMI, a new algorithm for culprit artery prediction was successfully tested.

Single-lead electrocardiographic variables in the detection of prior myocardial infarction with respect to Q-wave status and infarct age.

OBJECTIVES: Conventionally, the detection of prior myocardial infarction (MI) is based on QRS abnormalities, which may ignore non-Q-wave MI (NQMI). We aimed at finding automatically applicable quantitative ECG variables for diagnosing prior MI. METHODS: Body surface potential mapping (BSPM) was registered and automatically analyzed in 144 patients with prior MI and in 75 healthy controls. The MI was defined according to its age as recent or old, and Q-wave status as Q-wave MI (QMI) or NQMI. RESULTS: The QRSSTT integral, the STT integral and the T-wave apex amplitude applied in single, selected leads were found to be the optimal parameters in the detection of prior MI. The areas under the receiver-operating characteristic curves (AUC) were 89% for each, and detection was equal in old and recent MI (AUCs from 87 to 90%), and in QMI and NQMI (AUCs from 88 to 90%). CONCLUSIONS: The quantitative, automatically applicable single-lead variables comprising ventricular repolarization was effective in detecting prior MI, irrespective of the time elapsed from MI or the Q-wave status. These variables could be suitable for population studies and health screening purposes and are applicable to automatic ECG diagnostics of prior MI.

Localization of prior myocardial infarction by repolarization variables.

BACKGROUND: To find quantitative, automatically applicable electrocardiographic (ECG) variables for detecting prior myocardial infarction (MI) in different myocardial regions. METHODS: Observational study. Body surface potential mapping (BSPM) was recorded at rest, and automatically analyzed with regard to ECG parameters, blinded to the clinical characteristics of the study subjects, 144 patients with prior MI and 75 healthy controls. MI location was determined by cine angiography or echocardiography as anterior (66 patients), inferoposterior (89 patients), and lateral (15 patients). Patients' 12-lead ECG was interpreted according to Minnesota code (Q-wave MI in 97 patients). The QRSSTT, QRS, and STT integrals, and the T-apex amplitude in detecting prior anterior and inferoposterior MI were analyzed. RESULTS: The T-apex amplitude, QRSSTT integral, and STT integral were functional in detecting MI in all tested locations on a single-lead basis, with areas under receiver operating characteristic curves (AUC) of over 90% (p<0.001) in optimal sites. In the best leads AUC for the QRSSTT integral in anterior MI was 93% (CI 87-99%) and for the inferoposterior MI 92% (CI 88-97%). These repolarization variables outperformed the Minnesota code in all tested MI locations. They were also able to distinguish between anterior and inferoposterior MI with an AUC of >85% (p<0.001). CONCLUSIONS: Quantitative, automatically applicable single-lead repolarization variables detect prior MI irrespective of its location. They may simplify the screening for and localization of old infarctions as compared to the conventional ECG methods.