Magnitude Of ST-segment Elevation Research Articles

The Role of QRS Complex and ST-Segment in Major Adverse Cardiovascular Events Prediction in Patients with ST Elevated Myocardial Infarction: A 6-Year Follow-Up Study.

as a relatively high number of ST-segment elevation myocardial infarction (STEMI) patients develop major adverse cardiovascular events (MACE) following percutaneous coronary intervention (PCI), our aim was to determine the significance, and possible predictive value of QRS complex width and ST-segment elevation. our patient sample included 200 PCI-treated STEMI patients, which were divided into two groups based on the following duration of symptoms: (I) less than 6 h, and (II) 6 to 12 h. For every patient, an ECG was performed at six different time points, patients were followed for up to six years for the occurrence of MACE. the mean age was 60.6 ± 11.39 years, and 142 (71%) were male. The 6-12 h group had significantly wider QRS complex, higher ST-segment elevation, lower prevalence of ST-segment resolution as well as MACE prevalence (p < 0.05). ECG parameters, QRS width, and magnitude of ST-segment elevation were proved to be independent significant predictors of MACE in all measured time points (p < 0.05). Even after controlling for biomarkers of myocardial injury, these ECG parameters remained statistically significant predictors of MACE (p < 0.05). our study highlights that wider QRS complex and a more pronounced ST-segment elevation are associated with longer total ischemic time and higher risk of long-term MACE.

Characteristics of Inferior Myocardial Infarction With a Special Electrocardiographic Pattern (Aslanger) in Metabolic Syndrome

To evaluate the features of ST-segment elevation myocardial infarction with the Aslanger pattern in comparison with traditional forms of inferior myocardial infarction in metabolic syndrome. This study included 30 patients with inferior myocardial infarction in the presence of metabolic syndrome: 9 patients with the Aslanger electrocardiographic pattern (group 1, age 59.7 [58.4; 63.1] years) and the rest with one of the traditional forms (control group, 59.9 [57.2; 63.8] years, matched by all criteria of metabolic syndrome). All patients underwent primary percutaneous intervention with assessment of the angiographic picture. The magnitude of ST-segment elevation was measured in lead III at the J point and following 0.06 seconds, and the optimal threshold value of this indicator was determined for a new picture of myocardial infarction. The infarct-related artery in the Aslanger pattern was more often the circumflex artery (p=0.0099), and coronary thrombosis was characterized by a lower TIMI thrombus grade (p=0.014). SYNTAX values for the Aslanger pattern and for the traditional picture of inferior infarction with ST elevation in lead II≥III were higher than for a similar picture with ST elevation in lead III&gt;II. The level of cTnI at admission (p=0.013) and after 24 hours (p=0.0017), the platelet count (p=0.0011) and mean volume (p=0.0047) in group 1 had smaller values than with traditional inferior infarction. The ST elevation at J point and at J+0.06 s point for lead III with the Aslanger pattern was significantly lower than values of such shift in lead III&gt;II and lead II≥III with traditional inferior infarction (p&lt;0.001). An elevation value ≤1.5 mm at J point +0.06 s was a predictor of infarction with the Aslanger pattern. Constructing the ROC curve made it possible to determine that with the Aslanger pattern, the best cutoff value for this index is 2 mm. Myocardial infarction with the Aslanger pattern as compared with traditional lower infarction in metabolic syndrome is characterized by specific individual angiographic signs, lower ST segment elevation, cTnI level, and thrombotic disorders.

Correlation Between Magnitude of ST Segment Elevation and the Proximal Right Coronary Artery Lesion in Acute Inferior Myocardial Infarction

Introduction: The determination of the probable site of occlusion within RCA in acute inferior MI is very important because proximal occlusions are likely to cause greater myocardial damage and an early invasive strategy may be planned in such cases. Furthermore, identification of infarct-related artery and its site in acute inferior myocardial infarction not only guide decision regarding the urgency of revascularization but also guide to avoid therapy that may adversely affect the outcome. Objective: To predict the site of lesion in right coronary artery in acute inferior myocardial infarction by the magnitude of ST segment elevation in inferior leads (II, III and aVF). Methodology: This cross-sectional study was conducted in the Department of Cardiology, Sylhet MAG Osmani Medical College Hospital, from January 2014 to December 2015. A total of 50 consecutive patients with inferior MI who present within 12 hours of symptom onset and received fibrinolytic therapy were selected according to inclusion and exclusion criteria. Using 12-lead ECG, height of ST segment elevation in leads II, III and aVF were measured &amp; coronary angiography(CAG) was performed during index hospital period .CAG which showed culprit lesion in RCA were only taken for the study. The sum of STsegment elevation in inferior leads were then correlated with the proximal lesion in RCA. Results: The age of the patients ranged from 31 to 70 years with the mean age of 51.1 (SD 9.2) years. Majorities (88%) of the patients were male and ratio of male to female was 7.33:1.Out of 50 patients, 26(52%) had the lesion in proximal, 19 (38%) in mid and 05 (10%) in distal RCA. Patients with proximal RCA lesion showed a mean ST segment elevation of 12.5(SD 1.07) mm, with mid RCA lesion 8.5 (SD 0.80) mm and distal RCA lesion 6.5(SD 0.42) mm. There was a positive correlation of sum of ST segment elevation in inferior leads II, III and aVF to the proximal lesion in RCA (r=0.923, P &lt; 0.05). Conclusion: From the study it is concluded that the magnitude of ST segment elevation in inferior leads (II,III, aVF) can predict site of lesion in RCA in acute inferior wall myocardial infarction; the greater the sum of the height of ST segment elevation in inferior leads, the higher is the probability of lying the lesion in proximal right coronary artery. Bangladesh Heart Journal 2024; 39(1): 44-48

Correlation between Carbonic Anhydrase Isozymes and the Evolution of Myocardial Infarction in Diabetic Patients.

Simple SummaryHeart disease in diabetics presents distinctive characteristics both anatomically and physiopathologically compared to non-diabetics. In people with diabetes, high blood pressure has a high incidence (approximately one-third of diabetic patients have high blood pressure) and is a risk factor for diabetic macro- and microvascular complications. The correlation of these parameters could represent early markers of the prognosis and evolution of diabetic patients with acute myocardial infarction and their routine determination could be included in the biological algorithm of acute myocardial infarction, but understanding of this aspect must be deepened in the future. The results showed that diabetic patients develop acute myocardial infarction more frequently, regardless of age. The level of the enzymes of myocardial necrosis was higher in diabetics compared to non-diabetics, and acute coronary syndrome occurs mainly in diabetics with inadequate metabolic balance. Our research may provide useful information for the medical community.(1) Background: Myocardial infarction was, until recently, recognized as a major coronary event, often fatal, with major implications for survivors. According to some authors, diabetes mellitus is an important atherogenic risk factor with cardiac determinations underlying the definition of the so-called “diabetic heart”. The present study aims to establish a correlation between the evolution of myocardial infarction in diabetic patients, by determining whether lactic acid levels, the activity of carbonic anhydrase isoenzymes, and the magnitude of ST-segment elevation are correlated with the subsequent evolution of myocardial infarction. (2) Methods: The study analyzed 2 groups of 30 patients each: group 1 consisted of diabetic patients with acute myocardial infarction, and group 2 consisted of non-diabetic patients with acute myocardial infarction. Patients were examined clinically and paraclinical, their heart markers, lactic acid, and the activity of carbonic anhydrase I and II isozymes were determined. All patients underwent electrocardiogram and echocardiography analyses. (3) Results: The results showed that diabetics develop acute myocardial infarction more frequently, regardless of how much time has passed since the diagnosis. The value of myocardial necrosis enzymes was higher in diabetics than in non-diabetics, and acute coronary syndrome occurs mainly in diabetics with poor metabolic balance. Lethality rates in non-diabetic patients with lactic acid values above normal are lower than in diabetics. (4) Conclusions: Lactic acid correlated with the activity of isozyme I of carbonic dioxide which could be early markers of the prognosis and evolution of diabetic patients with acute myocardial infarction.

Magnitude of ST-segment Elevation Is Associated with Increased Acute Inflammatory Response and Myocardial Scar in Patients with Acute Myocardial Infarction Undergoing pPCI

ABSTRACT Background: The integrated ST segment elevation score (ISSTE) score objectively quantifies the ECG changes before and after primary percutaneous coronary intervention (pPCI) for ST segment elevation myocardial infarction (STEMI). The inflammatory response is a major component in scar formation and remodeling process of the myocardial tissue following myocardial infarction (MI). Cardiac magnetic resonance imaging (CMR) precisely quantifies the cardiac function and assesses the pattern of the myocardial scar tissue. The aim of the study was to evaluate the relations between the ISSTE score and: (1) acute inflammatory biomarkers and (2) extent of the myocardial scar determined by CMR in STEMI treated with pPCI. Material and methods: One hundred thirty STEMI patients were included in the study, who underwent pPCI in the first 12 hours from symptom debut. ISSTE-1 was calculated at presentation and 2 hours following pPCI (ISSTE-2). Inflammatory biomarkers were determined at admission and day 5, followed by LGE-CMR at 4 weeks, with quantification of cardiac function and extent of infarct size (IS) and transmurality. Patients were divided in low and high ISSTE groups based on the median values. Results: No significant differences were noted in terms of CMR parameters or inflammatory biomarkers and between the groups with low or high ISSTE-1. Significantly higher levels of day-5 hs-CRP (p = 0.03) and day-1 IL-6 (p = 0.02), MMP-9 (p = 0.05) were recorded in high ISSTE-2 groups. LV IS mass (23.11 ± 5.31 vs. 57.94 ± 8.33, p = 0.001), percentage (13.55 ± 6.22 vs. 27.15 ± 7.12, p = 0.001) and transmurality (p = 0.001) was significantly higher in ISSTE-2 group. ISSTE-2 significantly correlated with LV IS mass (r = 0.391, p &lt;0.0001), percentage (r = 0.541, p &lt;0.0001) high transmurality (r = 0.449, p &lt;0.0001) and LV EF (r = -0.397, p &lt;0.0001). Conclusions: A high ISSTE-2 score is associated with increased inflammatory response exhibited by elevated serum IL-6 and MMP-9 levels determined on the day of admission, and with persistently increased serum hs-CRP levels on day 5 of the acute event. A higher ISSTE-2 score is associated with larger myocardial scar extent expressed by IS, higher transmurality and reduced LV EF at 1-month LGE CMR follow-up.

P1437 Integrated ST segment elevation score as a new predictor of the myocardial scar extent determined with LGE-CMR at 1-month follow-up after STEMI

Abstract Funding Acknowledgements Funded by the research grant PlaqueImage, contract number 26/01.09.2016, SMIS code 103544, by the European Union and the Government of Romania Background The inflammatory response in the acute phase of a myocardial infarction, as well as in later phases contributes to the healing process of the infarcted myocardium and the left ventricular remodeling. Restoration and improvement of LV function highly depends on the magnitude of scar formation. Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging has been validated for an accurate determination of the myocardial scar size and transmurality. The recovery of ST segment elevation is a liable marker of vessel patency following PCI. Purpose The aim of the study was to validate a new integrated score of ST segment elevation score (ISSTE) as a new predictor of the myocardial scar tissue size, in relation with increased inflammatory biomarkers, with the extent of myocardial fibrosis at one month, assessed with LGE-CMR, after STEMI. Methods We included 65 patients with STEMI who underwent urgent revascularization with PCI in the first 12 hours from the onset of symptoms. The ISSTE was determined by summing the ST segment elevation in all registered ECG leads at presentation (ISSTE-1) and at 2 hours (ISSTE-2) after primary PCI. Blood samples were also collected at baseline and day-5 for determination of serum hs-CRP levels. At 1-month follow-up all patients under LGE-CMR (1.5T scanner) for evaluation of the myocardial scar extent (volume, percentage, transmurality). Results ISSTE-2 was significantly correlated with day-5 hs-CRP serum levels (r = 0.546, 95%CI: 0.030-0.832, p = 0.037), although no significant correlations were noted with baseline hs-CRP levels (r= 0.238, p = 0.407). There were no significant correlations between ISSTE-1 score and the myocardial scar percentage (r = 0.241, p = 0.11) or high transmurality volume (r = 0.194, p = 0.21), while ISSTE-2 significantly correlated with myocardial scar mass (r = 0.406, 95%CI: 0.107-0.637 p = 0.007) and high transmurality volume (r = 0.344, 95%CI: 0.0320-0.596, p = 0.0273). The restoration of the ST segment, reflected by the difference between ISSTE-1 and ISSTE -2 is correlated with the infarct size mass (r = 0.336, 95%CI: 0.0307 -0.584, p = 0.027). Conclusion The magnitude of ST segment elevation determined at 2 hours after PCI was associated with the inflammatory response at day 5 after STEMI and it may serve as a predictor for the extent of the myocardial scar tissue determined with LGE-CMR at 1 month following STEMI. The ISSTE-1 score calculated at presentation does not reflect extent of the affected myocardial tissue following PCI.

P1598Electrophysiological and structural characterization of acute atrial myocardial infarction

Abstract Background Atrial myocardial infarction may be a risk for atrial fibrillation. However, the electrophysiological and structural characteristics of the infarcted atrial myocardium are not well known. This study aimed to analyse the changes in local atrial electrograms and myocardial structure in an experimental model of isolated atrial myocardial infarction. Methods Five anesthetized, open-chest pigs were submitted to 4 hours of acute atrial myocardial ischemia induced by direct surgical clamping of atrial coronary branches originating from the right coronary artery. In all cases, we recorded simultaneously the 12-lead surface electrocardiogram (ECG) and the epicardial mapping of local atrial electrograms (17 x 12.5 mm patches containing 128 electrodes, with 1 mm inter-electrode distance) in a region close to the occluded branches and in control non-treated atria. The changes in local atrial QRS-ST segment and the amplitude of the P-wave of the ECG were sequentially analysed (Figure). The hearts were removed and processed for anatomopathological examination. Results Selective atrial coronary branch occlusion induced a patchy atrial myocardial necrosis with an irregular and abrupt border zone (circled areas in the Figure). During the first 15 min of ischemia, the local atrial electrograms showed increasing R waves, widening of QRS complex, and ST segment elevation leading to monophasic potentials (maximal ST segment at 30 min: from 0.2±0.7 mV to 1.9±1.4 mV, ANOVA p&lt;0.01). This period was followed by a phase of transient electrical recovery characterized by disappearance of monophasic potentials, reduction of ST segment elevation, and recovery of local electrical activation. After 60 min of occlusion, monophasic potentials reappeared and the magnitude of ST segment elevation decreased progressively during the ensuing 3 hours. The spatial transition from areas with monophasic potentials to normal electrograms encompassed 1 or 2 electrodes. The surface ECG showed increased duration of the P-wave (lead II at 3h occlusion: from 73.2±4.5 ms to 88.9±15.5 ms, ANOVA p&lt;0.05) with absence of ST segment changes. Atrial arrhythmias were not observed. Structural and electrical atrial changes Conclusion Selective occlusion of atrial coronary branches induced patchy atrial myocardial necrosis with abrupt anatomical and electrical border zone. The overt QRS and ST segment changes in local atrial electrograms resembled those described in acute ventricular myocardial ischemia, and were associated with widening of the P-wave on the surface ECG. Although acute ischemic arrhythmias were not observed, the atrial structural alterations might set the substrate for re-entrant arrhythmias late after the healing over process. Acknowledgement/Funding Supported by grants from ISCI-MINECO (FISPI17/00069), CIBERCV (CB16/11/00276), FEDER and Fundaciό “La Maratό” TV3 (20150830).

Ideal current of injury and R-wave sensingvalues for identifying optimized placement of right ventricular active-fixation pacing leads

To define the ideal COI and R-wave sensing values for optimized placement of right ventricular active-fixation pacing leads. Three hundred and six patients underwent right ventricular active-fixation lead implantation in our department from January 2013 to December 2014 were enrolled in this prospective pilot cohort study. According to the times needed for successful implantation, patients were divided into group SP (success poisoning after single procedure, n=229) and group MP (success poisoning after multiple procedures, n=77). Current of injury (COI) was characterized as the magnitude of ST-segment elevation. Pacing parameters were measured up to 10 minutes after lead fixation. (1) COI at 1 minute (COI1, (9.34±2.44)mV vs. (3.19±1.36)mV, P<0.001) and 10 minutes (COI10, (4.99±2.04)mV vs. (1.91±0.62)mV, P<0.001) after lead fixation was significantly higher in SP group compared to MP group. R-wave sensing measured at 10 minutes after lead fixation (R10 min) was also significantly higher in SP group than in MP group ((14.2±4.5)mV vs. (5.4±0.7)mV, P<0.001). Pacing threshold measured at 10 minutes after lead fixation was significantly lower ((0.65±0.18)V vs. (1.90±0.40)V, P<0.001) in SP group than in MP group. (2) The optimized placement of pacing lead was related with COI1(OR=0.247, 95%CI 0.098-0.623, P=0.003) and R10 min(OR=0.081, 95%CI 0.015-0.428, P=0.003). (3) The cut-off value of COI1 was 4.77 mV(sensibility 0.97, specificity 0.95), the cut-off value of R10 min was 7.25 mV (sensibility 0.96, specificity 1.00) for optimized lead fixation. After 3 months follow up, pacing threshold was (0.68±0.19)V, R-wave sensing was (12.1±3.6)mV, and pacing impedance was (543±107)Ω for right ventricular active-fixation pacing leads. COI1>4.77 mV and R10 min>7.25 mV are the ideal parameters for identifying optimized placement of right ventricular active-fixation pacing leads.

Inter-rater reliability of J-point location and measurement of the magnitude of ST segment elevation at the J-point on ECGs of STEMI patients by emergency department doctors

Introduction and objectivesIdentification of the J-point and measurement of ST segment elevation at the J-point are important for the diagnosis of ST-elevation myocardial infarction (STEMI). We conducted a study to...

Predictors of Ventricular Fibrillation at Reperfusion in Patients With Acute ST-Elevation Myocardial Infarction Treated by Primary Percutaneous Coronary Intervention

Ventricular fibrillation (VF) during reperfusion (rVF) in ST-segment elevation myocardial infarction (STEMI) is an infrequent but serious event that complicates coronary interventions. The aim of this study was to analyze clinical predictors of rVF in an unselected population of patients with STEMI treated with percutaneous coronary intervention (PCI). Consecutive patients with STEMI admitted to a tertiary care hospital for primary PCI from 2007 to 2012 were retrospectively assessed for the presence of rVF. Admission electrocardiograms, stored in a digital format, were analyzed for a maximal ST-segment elevation in a single lead and the sum of ST-segment deviations in all leads. Clinical, electrocardiographic, and angiographic characteristics were tested for associations with rVF using logistic regression analysis. Among 3,724 patients with STEMI admitted from 2007 to 2012, 71 (1.9%) had rVF. In univariate analysis, history of myocardial infarction, aspirin and β-blocker use, VF before PCI, left main coronary artery disease, inferior myocardial infarction localization, symptom-to-balloon time <360 minutes, maximal ST-segment elevation in a single lead >300 μV, and sum of ST-segment deviations in all leads >1,500 μV were associated with increased risk for rVF. In a multivariate analysis, sum of ST-segment deviations in all leads >1500 μV (odds ratio 3.7, 95% confidence interval 1.45 to 9.41, p = 0.006) before PCI remained an independent predictor of rVF. In-hospital mortality was 18.3% in the rVF group and 3.3% in the group without VF (p <0.001), but rVF was not an independent predictor of in-hospital death. In conclusion, the magnitude of ST-segment elevation before PCI for STEMI independently predicts rVF and should be considered in periprocedural arrhythmic risk assessment. Despite higher in-hospital mortality in patients with rVF, rVF itself has no independent prognostic value for prognosis.

Abstract 15688: Electrocardiographic Patterns Differentiating "Apical Ballooning" From Anterior Myocardial Infarction

Introduction: Left ventricular apical ballooning (AB) mimics anterior myocardial infarction (AMI). This study assessed if the ECG can differentiate between these two syndromes with a similar clinical presentation. Methods: Among 2086 patients (pts) with an ACS, 33 (1.6%) with AB were identified (29 f, 4 m, median age 77 years) and compared to 28 consecutive age and sex matched AMI pts undergoing PCI of the LAD with similar findings on LV angiography. Results: AB pts arrived at the hospital later after symptom onset (median 21 vs 5 hours; p&lt;0.001). On the admission ECG, the number of leads with ST-segment elevation (4 [3-6] vs 5 [5-7], p=0.005) and the magnitude of ST-segment elevation (0.7 [0.5-0.9] vs 0.9 [0.7-1.5] mV, p=0.002) were greater in AMI. Reciprocal ST-segment depression was similar (27% vs 54%, p=ns). A positive T wave in aVR was more frequent in AB (49% vs 7%, p&lt;0.001). During follow-up, AB pts had more leads with T-wave inversion (8 [8-9] vs 6 [5-8], p&lt;0.001) and a larger magnitude of T-wave inversion (2.9 [2.2-4.6] vs 1.4 [0.9-2.3] mV, p&lt;0.001). T-wave inversion was similar in I, aVL and V2-V5. AB pts, however, showed negative T-waves also in lead II (74% vs 22%, p&lt;0.001), III (34% vs 4%, p=0.004), aVF (51% vs 11%, p=0.001) and a positive T wave in aVR (100% vs 70%, p=0.005). The QTc interval was longer in AB (515 [482-543] vs 458 [435-484] ms, p&lt;0.001). An abnormal Q wave on admission was more frequent in AMI (21% vs 79%, p&lt;0.001) and persisted but was absent in AB at discharge (0% vs 61%, p&lt;0.001). Ventricular tachycardia was similar (2% vs 14%, p=ns) but atrial fibrillation occurred only in AB (21% vs 0%, p=0.013). The ECG normalized in all AB but in only 1 AMI pt (p&lt;0.001). Overall, despite a similar ejection fraction (54±15 vs 55±13 %) and lower troponin I values (7.5±6.9 vs 238±221 ng/ml, p&lt;0.001), AB pts developed significantly more adverse events compared to AMI pts (52% vs 18%, p&lt;0.008). Conclusion: ECG patterns in AB are significantly different from those in AMI. On admission, the extent of ST-segment elevation and the number of Q waves are greater in AMI. During follow-up, no Q wave, a longer QTc interval, a greater extent of T-wave inversion and a positive T wave in aVR are typical findings in AB. Adverse events are more frequent in AB than in AMI.

Usefulness of Sum of ST-Segment Elevation on Electrocardiograms (Limb Leads) for Predicting In-Hospital Complications in Patients With Stress (Takotsubo) Cardiomyopathy

Although the prognosis of patients with stress (takotsubo) cardiomyopathy is relatively favorable, serious complications occur in some patients. It is generally accepted that electrocardiography is an essential tool for the diagnosis of stress cardiomyopathy, with findings highly suggestive of the characteristics of myocardial damage. We tested the hypothesis that the quantitative analysis of electrocardiograhic changes can predict complications in stress cardiomyopathy. The study subjects were 85 patients with stress cardiomyopathy. A total of 34 patients developed ≥1 in-hospital complications (heart failure, intraventricular pressure gradient [>30 mm Hg], cardiogenic shock, ventricular tachycardia/fibrillation, and embolism). Patients with complications were likely to have a higher heart rate (96 ± 25 vs 76 ± 17 beats/min, p <0.001), larger sum of ST-segment elevation in 12 leads (median 10.5 mm; interquartile range 5.0 to 17.5 vs 3.0 mm, interquartile range 0 to 7.0; p <0.001) and extension of ST-segment elevation to limb leads (50% vs 12%, p <0.001) than those without complications. Multivariate logistic regression analysis identified heart rate (odds ratio 1.05, 95% confidence interval 1.02 to 1.07, p = 0.001) and sum of ST-segment elevation in 12 leads (odds ratio 1.24, 95% confidence interval 1.11 to 1.39, p <0.001) as significant and independent predictors of complications. Receiver operating characteristic analysis selected 5.5 mm as the best cutoff value of sum of ST-segment elevation in 12 leads for the prediction of complications, with a sensitivity and specificity of 74% and 73%, respectively, and area under the curve of 0.81 (95% confidence interval 0.72 to 0.90, p <0.001). The results suggest that the extent and magnitude of ST-segment elevation on the electrocardiogram are potentially useful predictors of in-hospital complications in patients with stress cardiomyopathy.

Abstract 9111: The Summation of ST-Segment Elevation is a Novel Predictor for Complications in Patients with Stress (Takotsubo) Cardiomyopathy

Background: Although the prognosis of stress (Takotsubo) cardiomyopathy (SC) is relatively favorable, it sometimes leads to serious complications. It is generally accepted that electrocardiogram (ECG) highly suggestive of the characteristics of myocardial damage is essential tool for diagnosis of SC. We assessed the hypothesis that serial change and quantitative analysis of ECG are associated with following adverse events in patients with SC. Methods and Results: The study patients consisted of 85 patients with SC. A total of 34 patients suffered from 1 or more in-hospital adverse events such as heart failure, intraventricular pressure gradient (&gt;30 mmHg), cardiogenic shock, ventricular tachycardia/fibrillation, and cerebral embolism. Of them, 2 patients died of cardiogenic shock. Patients with adverse events had higher heart rate (96±25 vs. 76±17 bpm, p&lt;0.001) and greater summation of ST-segment elevation in 12 leads (ΣSTE) (10.5 [5.0 to 17.5] mm vs. 3.0 [0 to 7.0] mm; p&lt;0.001) than those with non-adverse event. A multivariate logistic regression analysis showed that heart rate and ΣSTE were independent predictive variables (Table) and the best cutoff level of ΣSTE for prediction of adverse events was 5.5 mm based on a receiver operating characteristic curve. The ST-segment elevation in adverse events group extended up to limb leads as well as precordial leads compared with that in non-adverse evnets group (50% vs. 12%; p&lt;0.001). However, a significant difference was not observed regarding ST resolution &lt;50% at 24 hour after hospital admission clinically suggestive of prognostic impairment of SC between 2 groups (38% vs. 43%; p=0.80). Conclusions: Electrocardiographic extent and magnitude of ST-segment elevation can predict in-hospital adverse events following SC. Our findings may help to explain the missing link between ECG changes and the severity of catecholamine-induced myocardial damage deeply involved in fatal and non-fatal complications.

A New Electrocardiographic Criterion to Differentiate Between Takotsubo Cardiomyopathy and Anterior Wall ST-Segment Elevation Acute Myocardial Infarction

Several studies have examined the ability of electrocardiography to differentiate between takotsubo cardiomyopathy (TC) and anterior wall acute ST-segment elevation myocardial infarction (AA-STEMI). In those studies, the magnitude of ST-segment elevation was not measured at the J point. The American Heart Association, American College of Cardiology Foundation, and Heart Rhythm Society guidelines recommend that the magnitude of ST-segment elevation should be measured at the J point. Accordingly, the aim of this study was to retrospectively examine whether electrocardiography, using the magnitude of ST-segment elevation measured at the J point, could differentiate 62 patients with TC from 280 with AA-STEMI. Patients with AA-STEMI were divided into following subgroups: 140 with left anterior descending coronary artery occlusions proximal to the first diagonal branch (AA-STEMI-P), 120 with left anterior descending occlusions distal to the first diagonal branch and proximal to the second diagonal branch (AA-STEMI-M), and 20 with left anterior descending occlusions distal to the second diagonal branch (AA-STEMI-D). TC had a much lower prevalence of ST-segment elevation ≥1 mm in lead V(1) (19.4%) compared to AA-STEMI (80.4%, p <0.01), AA-STEMI-P (80.7%, p <0.01), AA-STEMI-M (80%, p <0.01), and AA-STEMI-D (80%, p <0.01). ST-segment elevation ≥1 mm in ≥1 of leads V(3) to V(5) without ST-segment elevation ≥1 mm in lead V(1) identified TC with sensitivity of 74.2% and specificity of 80.6%. Furthermore, this criterion could differentiate TC from each AA-STEMI subgroup, with similar diagnostic values. In conclusion, using the magnitude of ST-segment elevation measured at the J point, a new electrocardiographic criterion is proposed with an acceptable ability to differentiate TC from AA-STEMI.

Prognostic Impact of Early ST-Segment Resolution and Biochemical Markers in Patients With ST-Elevation Myocardial Infarction

Refer to the page 372-378 Considerable variability exists for the reported mortality risk among patients with ST-elevation myocardial infarction (STEMI) and who are treated with primary percutaneous coronary intervention (PCI). The diversity in the clinical out comes for these patients challenges the physician at each step: risk stratification, planning the treatment and monitoring the response to PCI. In this regard, the current guidelines for the treatment of patients with acute coronary syndrome (ACS) recommend risk stratification using a variety of clinical vari ables. Clinical variables such as biomarkers, electrocardiography (ECG), and the imaging modalities have been studied for whether these variables may improve the risk assessment and clinical care. The standard 12-lead ECG has been used as the single most important diagnostic tool for the evaluation of ACS. Measurement via ECG is very useful and informative for determining the quality of reperfusion in patients with acute STEMI. The degree of ST segment deviation also confers prognostic information. 1) Since it was first documented in 1971 in an animal study that the magnitude of ST segment elevation was well correlated well with depressed myocardial creatine kinase activity as well as myocardial necrosis, 2) the degree of ST segment elevation has been used as an

Effect of High-Dose Intracoronary Adenosine Administration During Primary Percutaneous Coronary Intervention in Acute Myocardial Infarction: A Randomized Controlled Trial

Effect of High-Dose Intracoronary Adenosine Administration During Primary Percutaneous Coronary Intervention in Acute Myocardial Infarction: A Randomized Controlled Trial

Concordant improvements in coronary flow reserve and ST‐segment resolution during percutaneous coronary intervention for acute myocardial infarction: A benefit of postconditioning

To assess the effect of ischemic postconditioning on indices of coronary microvascular function during percutaneous coronary intervention (PCI) for acute ST segment elevation myocardial infarction (STEMI). Myocardial tissue level perfusion remains suboptimal in many patients with STEMI despite restoration of antegrade flow in the epicardial coronary artery. Twenty-four patients with an evolving anterior STEMI were randomized to undergo a previously-validated ischemic postconditioning protocol or usual care during PCI. The extent of resolution of ST segment elevation along with Doppler-tip catheter velocimetry was used as indices of myocardial reperfusion and microvascular function, respectively. Postconditioned patients exhibited a greater, and therefore more rapid, extent of ST segment resolution (postconditioning, 70% +/- 15%; control, 48% +/- 16%; P = 0.0002) by the end of the procedure. Postconditioned patients also exhibited a greater hyperemic coronary vasodilator response at the completion of the procedure (coronary flow velocity reserve, CFVR: postconditioning, 2.2 +/- 0.1; control, 1.5 +/- 0.1; P < 0.0001). The end-procedure CFVR was directly related to the extent of the ST segment resolution (r = 0.85) but inversely related to the absolute magnitude of ST segment elevation at end procedure (r = -0.76). Peak serum creatine kinase was significantly lower in postconditioned patients (postconditioning, 1,524 +/- 435 IU/l; control, 1,862 +/- 561 IU/l; P = 0.03). Ischemic postconditioning, as described, can be expeditiously performed during PCI for STEMI. Concordant changes in coronary flow reserve and ST segment resolution, measures of microcirculatory function, and myocardial perfusion, were greater in postconditioned patients.

Role of Streptomycin‐Sensitive Stretch‐Activated Channel in Chest Wall Impact Induced Sudden Death (Commotio Cordis)

Deaths secondary to low-energy impacts to the precordium in young individuals (commotio cordis) have been reported with increasing frequency. In a swine model, baseball impacts induce ventricular fibrillation when directed at the center of the left ventricle during the vulnerable portion of repolarization just prior to the T-wave peak. It has been hypothesized that activation of stretch-sensitive channels could be crucial for this electrophysiological phenomenon. In this study, a nonselective stretch-activated cation channel was pharmacologically blocked prior to chest blows to determine whether this channel represents a possible pathway by which commotio cordis events occur. In a randomized and blinded experiment, 12 swine (mean 17.1 +/- 2.5 kg) received either 2-g streptomycin intramuscularly (mean serum concentration 115 +/- 18 muM) or sterile water prior to chest impact. Each animal received six precordial impacts with a baseball propelled at 40 mph. There was no significant difference in the frequency of induced VF in the animals administered streptomycin (10 of 19 impacts: 53%) compared to those control animals receiving only sterile water (10 of 31: 32%) (P = 0.15). However, the magnitude of ST segment elevation was less in the streptomycin-treated animals (19 +/- 19 mV) versus controls (61 +/- 46 mV) (P = 0.015). Streptomycin did not alter the frequency of ventricular fibrillation in our commotio cordis model, indicating that the stretch-activated channel is not implicated in the genesis of chest blow-induced cardiac arrest. However, streptomycin did reduce ST elevation following impact suggesting that the stretch-activated channel may play a role in ST segment elevation following chest wall blows.

Selective activation of the K(+)(ATP) channel is a mechanism by which sudden death is produced by low-energy chest-wall impact (Commotio cordis).

Sudden death due to relatively innocent chest-wall impact has been described in young individuals (commotio cordis). In our previously reported swine model of commotio cordis, ventricular fibrillation (with T-wave strikes) and ST-segment elevation (with QRS strikes) were produced by 30-mph baseball impacts to the precordium. Because activation of the K(+)(ATP) channel has been implicated in the pathogenesis of ST elevation and ventricular fibrillation in myocardial ischemia, we hypothesized that this channel could be responsible for the electrophysiologic findings in our experimental model and in victims of commotio cordis. In the initial experiment, 6 juvenile swine were given 0.5 mg/kg IV glibenclamide, a selective inhibitor of the K(+)(ATP) channel, and chest impact was given on the QRS. The results of these strikes were compared with animals in which no glibenclamide was given. In the second phase, 20 swine were randomized to receive glibenclamide or a control vehicle (in a double-blind fashion), with chest impact delivered just before the T-wave peak. With QRS impacts, the maximal ST elevation was significantly less in those animals given glibenclamide (0.16+/-0.10 mV) than in controls (0.35+/-0.20 mV; P=0.004). With T-wave impacts, the animals that received glibenclamide had significantly fewer occurrences of ventricular fibrillation (1 episode in 27 impacts; 4%) than controls (6 episodes in 18 impacts; 33%; P=0.01). In this experimental model of commotio cordis, blockade of the K(+)(ATP) channel reduced the incidence of ventricular fibrillation and the magnitude of ST-segment elevation. Therefore, selective K(+)(ATP) channel activation may be a pivotal mechanism in sudden death resulting from low-energy chest-wall trauma in young people during sporting activities.

The magnitude of ST-segment elevation during catecholamine infusion correlates to I-123 metaiodobenzylguanidine defect after Q-wave myocardial infarction

The magnitude of ST-segment elevation during catecholamine infusion correlates to I-123 metaiodobenzylguanidine defect after Q-wave myocardial infarction