Persistent negative T waves in the infarct-related leads as an independent predictor of poor long-term prognosis after acute myocardial infarction

The prognostic significance of Q waves and T wave inversions in the ECG of patients with STEMI: A substudy of the TOTAL trial

BACKGROUND

The prognostic significance of Q waves and T-wave inversions (TWI) combined and separately in STEMI patients undergoing primary PCI has not been well established in previous studies.

METHODS

We included 7,831 patients from the TOTAL trial and divided the patients into categories based on Q waves and TWIs in the presenting ECG. The primary outcome was a composite of cardiovascular death, recurrent myocardial infarction (MI), cardiogenic shock or new or worsening NYHA class IV heart failure within one year. The study evaluated the effect of Q waves and TWI on the risk of primary outcome and all-cause death, and whether patient benefit of aspiration thrombectomy differed between the ECG categories.

RESULTS

Patients with Q+TWI+ (Q wave and TWI) pattern had higher risk of primary outcome compared to patients with Q-TWI- pattern [33 (10.5%) vs. 221 (4.2%); adjusted hazard ratio (aHR) 2.10; 95% CI, 1.45-3.04; p<0.001] within 40-days' period. When analyzed separately, patients with Q waves had a higher risk for the primary outcome compared to patients with no Q waves in the first 40 days [aHR 1.80; 95% CI, 1.48-2.19; p<0.001] but there was no additive risk after 40 days. Patients with TWI had a higher risk for primary outcome only after 40 days when compared to patients with no TWI [aHR 1.63; 95% CI, 1.04-2.55; p=0.033]. There was a trend towards a benefit of thrombectomy in patients with the Q+TWI+ pattern.

CONCLUSIONS

Q waves and TWI combined (Q+TWI+ pattern) in the presenting ECG is associated with unfavourable outcome within 40-days. Q waves tend to affect short-term outcome, while TWI has more effect on long-term outcome.

The prognostic significance of T-wave inversion according to ECG lead group during long-term follow-up in the general population

Background

Inverted T waves in the electrocardiogram (ECG) have been associated with coronary heart disease (CHD) and mortality. The pathophysiology and prognostic significance of T‐wave inversion may differ between different anatomical lead groups, but scientific data related to this issue is scarce.

Methods

A representative sample of Finnish subjects (n = 6,354) aged over 30 years underwent a health examination including a 12‐lead ECG in the Health 2000 survey. ECGs with T‐wave inversions were divided into three anatomical lead groups (anterior, lateral, and inferior) and were compared to ECGs with no pathological T‐wave inversions in multivariable‐adjusted Fine–Gray and Cox regression hazard models using CHD and mortality as endpoints.

Results

The follow‐up for both CHD and mortality lasted approximately fifteen years (median value with interquartile ranges between 14.9 and 15.3). In multivariate‐adjusted models, anterior and lateral (but not inferior) T‐wave inversions associated with increased risk of CHD (HR: 2.37 [95% confidence interval 1.20–4.68] and 1.65 [1.27–2.15], respectively). In multivariable analyses, only lateral T‐wave inversions associated with increased risk of mortality in the entire study population (HR 1.51 [1.26–1.81]) as well as among individuals with no CHD at baseline (HR 1.59 [1.29–1.96]).

Conclusions

The prognostic information of inverted T waves differs between anatomical lead groups. T‐wave inversion in the anterior and lateral lead groups is independently associated with the risk of CHD, and lateral T‐wave inversion is also associated with increased risk of mortality. Inverted T wave in the inferior lead group proved to be a benign phenomenon.

The high-risk ECG pattern of ST-elevation myocardial infarction: A substudy of the randomized trial of primary PCI with or without routine manual thrombectomy (TOTAL trial)

BACKGROUND

Useful tools for risk assessment in patients with STEMI are needed. We evaluated the prognostic impact of the evolving myocardial infarction (EMI) and the preinfarction syndrome (PIS) ECG patterns and determined their correlation with angiographic findings and treatment strategy.

METHODS

This substudy of the randomized Trial of Routine Aspiration Thrombectomy with PCI versus PCI Alone in Patients with STEMI (TOTAL) included 7860 patients with STEMI and either the EMI or the PIS ECG pattern. The primary outcome was a composite of death from cardiovascular causes, recurrent MI, cardiogenic shock, or New York Heart Association (NYHA) class IV heart failure within one year.

RESULTS

The primary outcome occurred in 271 of 2618 patients (10.4%) in the EMI group vs. 322 of 5242 patients (6.1%) in the PIS group [AdjustedHR, 1.54; 95% CI, 1.30 to 1.82; p < .001]. The primary outcome occurred in the thrombectomy and PCI alone groups in 131 of 1306 (10.0%) and 140 of 1312 (10.7%) patients with EMI [HR 0.94; 95% CI, 0.74-1.19] and 162 of 2633 (6.2%) and 160 of 2609 (6.1%) patients with PIS [HR 1.00; 95% CI, 0.81-1.25], respectively (p_interaction = 0.679).

CONCLUSIONS

Patients with the EMI ECG pattern proved to have an increased rate of the primary outcome within one year compared to the PIS pattern. Routine manual thrombectomy did not reduce the risk of primary outcome within the different dynamic ECG patterns. The PIS/EMI dynamic ECG classification could help to triage patients in case of simultaneous STEMI patients with immediate need for pPCI.

Persistent T-wave inversion predicts myocardial damage after ST-elevation myocardial infarction

BACKGROUND

Persistent T-wave inversion (PTI) after ST-elevation myocardial infarction (STEMI) is associated with worse clinical outcome; however, the underlying mechanism between PTI and poor prognosis is incompletely understood. We sought to investigate the relationship between PTI and myocardial damage assessed by cardiac magnetic resonance (CMR) following STEMI.

METHODS

In this prospective observational study, we included 142 consecutive revascularized STEMI patients. Electrocardiography to determine the presence and amplitude of PTI and pathological Q-waves was conducted 4months after infarction. CMR was performed within 1week after infarction and at 4months follow-up to evaluate infarct characteristics and myocardial function.

RESULTS

Patients with PTI (n=103, 73%) showed a larger acute (21[11-29] vs. 6[1-13]%; p<0.001) and chronic infarct size (IS) (14[8-19] vs. 3[1-8]%; p<0.001) and more frequently microvascular obstruction (59 vs. 33%; p=0.02). The association between PTI and chronic IS remained significant (odds ratio: 9.02, 95%CI 3.49-23.35; p<0.001) after adjustment for pathological Q-wave and other IS estimators (high-sensitivity cardiac troponin T and C-reactive protein, N-terminal pro B-type natriuretic peptide, culprit vessel, pre-interventional TIMI flow). The value of PTI amplitude for the prediction of large chronic IS>11% (AUC: 0.84, 95%CI 0.77-0.90) was significantly higher compared to Q-wave amplitude (AUC: 0.72, 95%CI 0.63-0.80; p=0.009); the combination of PTI with pathological Q-wave (Q-wave/T-wave score) led to a net reclassification improvement of 0.43 (95% CI 0.29-0.57; p<0.001) as compared to PTI alone.

CONCLUSIONS

PTI following STEMI is independently and incrementally associated with more extensive myocardial damage as visualized by CMR. An electrocardiographic score combining PTI with pathological Q-wave allows for a highly accurate IS estimation post-STEMI.

Left Ventricular Aneurysm May Not Manifest as Persistent ST Elevation on Electrocardiogram

Patient: Male, 67

Final Diagnosis: Left Ventricular aneurysm post myocardial infarction

Symptoms: Chest pain

Medication: Dual antiplatelet therapy • anticoagulation

Clinical Procedure: Cardiac catheterization

Specialty: Cardiology

Prominent T wave in V2 with respect to V6 as a sign of lateral myocardial infarction

BACKGROUND

In the absence of confounding electrocardiographic features, a prominent R wave in leads V1-V2 reflects a lateral myocardial infarction (MI). We hypothesized that repolarization abnormalities in V1-V2 could also reflect a lateral MI.

METHODS

We retrospectively selected a group of 57 patients with a recent or previous first Q-wave MI involving left ventricular (LV) inferior and/or lateral wall at contrast-enhanced cardiac magnetic resonance (CMR). The location and extent of the MI at CMR were compared with electrocardiographic features.

RESULTS

The infarction was located in the inferior wall in 12 patients (21%), in the lateral wall in 8 (14%), and in both walls in 37 patients (65%). Infarct size corresponded to 16.8 (SD 9.0%) of LV myocardium. Infarct extent in the inferior and lateral wall (8.3%, SD 7.2% vs. 8.4%, SD 7.5% of LV myocardium) did not differ significantly. Using multiple linear regression analysis, inferior Q-waves and inferior negative T waves were directly associated with infarct extent in the inferior wall (p = 0.014 and p = 0.010, respectively). A prominent R wave in V1 and a prominent anterior T wave (expressed by the T wave amplitude in V2 minus its amplitude in V6) were directly associated with MI extent in the lateral wall (p = 0.008 and p = 0.018), while inferior negative T waves were negatively associated (p = 0.006).

CONCLUSIONS

In patients with MI of the inferior and/or lateral wall, a prominent T wave in V2 with respect to V6 reflects greater infarct extent in the lateral wall.

Assessment of myocardial infarct size with body surface potential mapping: validation against contrast-enhanced cardiac magnetic resonance imaging

BACKGROUND

Assessment of myocardial infarct (MI) size is important for therapeutic and prognostic reasons. We used body surface potential mapping (BSPM) to evaluate whether single-lead electrocardiographic variables can assess MI size.

METHODS

We performed BSPM with 120 leads covering the front and back chest (plus limb leads) on 57 patients at different phases of MI: acutely, during healing, and in the chronic phase. Final MI size was determined by contrast-enhanced cardiac magnetic resonance imaging (DE-CMR) and correlated with various computed depolarization- and repolarization-phase BSPM variables. We also calculated correlations between BSPM variables and enzymatic MI size (peak CK-MBm).

RESULTS

BSPM variables reflecting the Q- and R wave showed strong correlations with MI size at all stages of MI. R width performed the best, showing its strongest correlation with MI size on the upper right back, there representing the width of the "reciprocal Q wave" (r = 0.64-0.71 for DE-CMR, r = 0.57-0.64 for CK-MBm, P < 0.0001). Repolarization-phase variables showed only weak correlations with MI size in the acute phase, but these correlations improved during MI healing. T-wave variables and the QRSSTT integral showed their best correlations with DE-CMR defined MI size on the precordial area, at best r = -0.57, P < 0.0001 in the chronic phase. The best performing BSPM variables could differentiate between large and small infarcts at all stages of MI.

CONCLUSIONS

Computed, single-lead electrocardiographic variables can estimate the final infarct size at all stages of MI, and differentiate large infarcts from small.

The relationship between serial postinfarction T wave changes and infarct size and ventricular function as determined by cardiac magnetic resonance imaging

BACKGROUND

The value of sequential T wave changes on the electrocardiogram (ECG) has less well been described than ST-segment changes in the follow-up of patients with myocardial infarction (MI). We investigated whether the amplitude of T wave positivity correlates with infarct size (IS) and left ventricular ejection fraction (LVEF) measured using cardiac magnetic resonance imaging 3 months after reperfusion therapy.

MATERIALS AND METHODS

Fifty-five patients with a first acute MI referred for primary percutaneous coronary intervention were included. Electrocardiograms were analyzed within 4 hours after reperfusion and at 3 months, measuring T wave ampitudes in 2 contiguous infarct-related leads, summed up as one value called T wave amplitude. Cardiac magnetic resonance imaging was performed at 3 months of follow-up. Correlations between T wave amplitude, IS, and LVEF were tested with Pearson r correlation coefficient test. Subanalyses were performed using a 2-sample t test.

RESULTS

A good correlation was found between LVEF and IS (r = -0.7, P < .0001). Most of the patients had inferior MI location (69%). In this group, there were significant positive correlations between the amount of T wave positivity and both IS (r = -0.40, P = .012) and LVEF (r = 0.33, P = .043). Results were similar in patients with and without an increase in T wave amplitude during follow-up.

CONCLUSIONS

In this study of patients with reperfused MI, patients with inferior locations demonstrated a statistically significant relationship between the amount of positivity of T wave amplitude and both IS and LVEF measured at 3 months. Furthermore, these results were independent of whether the T wave positivity was persistent or evolutionary between the immediate postreperfusion and 3-month ECG recordings.

Utility of nonspecific resting electrocardiographic features for detection of coronary artery stenosis by computed tomography in acute chest pain patients: from the ROMICAT trial

Twelve-lead surface electrocardiography (ECG) and computed tomography (CT) are used to evaluate for myocardial ischemia and coronary artery disease (CAD), respectively. We aimed to determine features on resting ECG that predict coronary artery stenosis by cardiac CT. In 309 acute chest pain patients, we compared the initial triage resting ECG to contrast-enhanced 64-slice cardiac CT angiography. We assessed for 6 quantitative (QT interval, QTc interval, QTc > 440 ms, gender-specific QTc, QT dispersion and QRS duration) and 4 qualitative ECG parameters (ST depression >0.05 to ≤0.1 mV, T wave inversion ≥0.1 mV, T wave flattening, and any T wave abnormalities) and for the presence of coronary stenosis by CT (>50% luminal narrowing). Specificities of these ECG parameters were excellent (83.6-97.0%) while sensitivities were poor (12.2-29.3%). For coronary stenosis detection, the ECG features with the greatest performance were the presence of ST depression (positive likelihood ratio [LR+] 4.09) and T wave inversion (LR+ 4.58). In multivariable analyses, the risk for coronary stenosis increased by 33-41% for every 20 ms prolongation of the QTc interval after adjusting for age, gender, and cardiac risk factors or adjustment for Framingham risk score. Similarly, there was an increase of fourfold with the presence of ST depression >0.05 to ≤0.1 mV or T wave inversion ≥0.1 mV. In acute chest pain patients, resting ECG features of QTc interval prolongation, mild ST depression, and T wave inversion are independently associated with the presence of CT coronary stenosis and their presence suggests an increase risk of CAD.

Persistent ischaemic ECG abnormalities on repeated ECG examination have important prognostic value for cardiovascular disease beyond established risk factors: a population-based study in middle-aged men with up to 32 years of follow-up

OBJECTIVE

To determine the effect of new, persistent or reverted ischaemic ECG abnormalities at ages 50 and 70 years on the risk of subsequent cardiovascular disease.

DESIGN, SETTING AND PARTICIPANTS

A prospective community-based observational cohort of 50-year-old men in Sweden, followed for 32 years. 2322 men of age 50 years participated in 1970-3, and 1221 subjects were re-examined at the age of 70 years.

MAIN OUTCOME MEASURES

Myocardial infarction (MI), cardiovascular mortality and overall mortality.

RESULTS

At 50 years of age, after adjusting for established conventional risk factors, T wave abnormalities, ST segment depression, major Q/QS pattern and ECG-left ventricular hypertrophy were all found to be independent risk factors for the main outcome measures during the 32 years of follow-up. When ECG variables were re-measured at 70 years of age, they were still found to be independent risk factors for the mortality outcomes, but lost in significance for prediction of MI. Regarding mortality, it was twice as dangerous to have persistent T wave abnormalities (HR 4.63; 95% CI 2.18 to 9.83) or ST segment depression (HR 5.66; 95% CI 1.77 to 18.1), as with new T wave abnormalities (HR 2.20; 95% CI 1.48 to 3.29) or ST segment depression (HR 2.55; 95% CI 1.74 to 3.75), developing between ages 50 and 70 years. The addition of "ECG indicating ischaemia" significantly increased the predictive power of the Framingham score (p<0.001).

CONCLUSIONS

It is worthwhile to obtain serial ECGs for proper risk assessment, since persistent ST-T abnormalities carried twice as high a risk for future mortality compared with new or reverted abnormalities.

T wave abnormalities, high body mass index, current smoking and high lipoprotein (a) levels predict the development of major abnormal Q/QS patterns 20 years later. A population-based study

BACKGROUND

Most studies on risk factors for development of coronary heart disease (CHD) have been based on the clinical outcome of CHD. Our aim was to identify factors that could predict the development of ECG markers of CHD, such as abnormal Q/QS patterns, ST segment depression and T wave abnormalities, in 70-year-old men, irrespective of clinical outcome.

METHODS

Predictors for development of different ECG abnormalities were identified in a population-based study using stepwise logistic regression. Anthropometrical and metabolic factors, ECG abnormalities and vital signs from a health survey of men at age 50 were related to ECG abnormalities identified in the same cohort 20 years later.

RESULTS

At the age of 70, 9% had developed a major abnormal Q/QS pattern, but 63% of these subjects had not been previously hospitalized due to MI, while 57% with symptomatic MI between age 50 and 70 had no major Q/QS pattern at age 70. T wave abnormalities (Odds ratio 3.11, 95% CI 1.18-8.17), high lipoprotein (a) levels, high body mass index (BMI) and smoking were identified as significant independent predictors for the development of abnormal major Q/QS patterns. T wave abnormalities and high fasting glucose levels were significant independent predictors for the development of ST segment depression without abnormal Q/QS pattern.

CONCLUSION

T wave abnormalities on resting ECG should be given special attention and correlated with clinical information. Risk factors for major Q/QS patterns need not be the same as traditional risk factors for clinically recognized CHD. High lipoprotein (a) levels may be a stronger risk factor for silent myocardial infarction (MI) compared to clinically recognized MI.

Ischemia-induced ST-segment elevation: classification, prognosis, and therapy

The standard 12-lead electrocardiogram (ECG) remains the most useful tool for the diagnosis, early risk stratification, triage, and guidance of therapy in patients with acute coronary syndromes. However, the initial and the terminal part of the QRS complex, the ST segments, and the T waves are influenced by anatomical and metabolic factors such as the "myocardium at risk" and "severity" and "duration" of ischemia. Moreover, there are complex interactions between all these factors. The ECG can identify potential candidates for reperfusion therapy as well as the completeness and success of reperfusion, whereas it can also identify those patients who will have no benefit from reperfusion because of either late arrival or nonischemic etiologies of ECG changes. These patients may have a "pseudo" ST-elevation acute myocardial infarction (STEAMI) or "pseudo-pseudo" STEAMI. The presence of Q waves and additional ST-segment depression and T-wave inversion on the admission ECG in patients with STEAMI may provide us information regarding the potential myocardial reserves, and various ECG scoring systems are in current use for that purpose. The pattern and timing of changes in Q waves, ST segment, and T waves may all be markers of the patency status of the infarct-related artery. We review and discuss each of the dynamic ECG variables during ischemia and reperfusion: the initial QRS (Q and R waves), the terminal QRS (Sclarovsky-Birnbaum score), the ST segment, and the T waves.

Electrocardiogram of acute ST-elevation myocardial infarction: the significance of the various "scores"

The Electrocardiogram has extensively been used for evaluation and triage of patients with acute chest pain. The clinician admitting a patient with ST elevation acute myocardial infarction should be able to estimate the size and location of the ischemic area at risk, how much of the ischemic myocardium has already undergone irreversible necrosis by the time of presentation, and the "severity of ischemia" (or what is the rate of progression of necrosis as long as ischemia continues). The electrocardiographic variables that are used to make these estimates are the initial portion of the QRS (Q and R waves), the terminal portion of the QRS (the S waves and the J-point), the ST segment, and the configuration of the T waves. This editorial discuss the ability to predict each of the "physiological" parameters using the above mentioned electrocardiographic variables.

Determinants of persistent negative T waves and early versus late T wave normalisation after acute myocardial infarction

OBJECTIVE

To determine whether persistent versus early or delayed T wave normalisation of negative T waves after acute myocardial infarction is determined by the myocardial state, the treatment strategy, or both.

DESIGN

127 consecutive patients with a first acute myocardial infarction and > or = 2 negative T waves on the 24-36 hour ECG were studied. They underwent dobutamine stress echocardiography and coronary angiography during the first week. ECG was recorded at hospital discharge and at a mean (SD) of 4 (1) months.

SETTING

University hospital.

RESULTS

T wave normalisation was observed in 88 patients (early at discharge in 19 and delayed at four months in 69). Early T wave normalisation was associated with sustained contractile reserve during dobutamine stress (13 of 19 (68%)), whereas delayed T wave normalisation was observed mainly in patients with an ischaemic response (49 of 69 (71%)). The persistence of negative T waves was associated with an ischaemic response (21 of 39 (54%)) or persistent akinesis (17 of 39 (44%)). Among patients with an ischaemic response to dobutamine, in-hospital elective angioplasty was an independent determinant of delayed T wave normalisation (39 of 49 v 4 of 21 patients with persistent negative T waves at four months, p < 0.0001).

CONCLUSIONS

Early T wave normalisation is associated with dobutamine induced, sustained improvement indicating myocardial stunning. Delayed normalisation is observed mainly in patients with ischaemic myocardium who have undergone revascularisation. Persistent negative T waves correspond to either extensive necrosis or non-revascularised, jeopardised myocardium.

Prediction of decrease in myocardial perfusion defect size and severity during a 3-month follow-up by the degree of acute resolution of electrocardiographic changes

Myocardial perfusion in infarct-related artery (IRA) distribution improves progressively until a few months after successful reperfusion therapy. We assessed the rate of electrocardiographic (ECG) stage dynamics to predict perfusion improvement after mechanical, thrombolytic, or spontaneous recanalization of IRA. Thirteen patients were divided into group A (n = 8, with > or = 2 ECG stages per 2-day change rate) and group B (n = 5, no rapid change of ECG stages). There were no significant technetium Tc 99m sestamibi scintigraphic differences between the groups 3 days after recanalization; however, after 3 months, perfusion deficit size (2.8 +/- 1.8 vs 4.8 +/- 1.2, P < or = .03) and severity (1.8 +/- 0.9 vs 3.0 +/- 0, P < or = .03) were smaller in group A vs group B. The prediction sensitivity of the method was 87.5% for decrease in size and 100% for decrease in severity of perfusion defect; the specificity was 80% and 100%, respectively. A change rate of 2 or more ECG stages per 2 days predicts follow-up improvement of myocardial perfusion after IRA recanalization.

Normalization of negative T waves in the chronic stage of Q wave anterior myocardial infarction as a predictor of myocardial viability

We investigated whether spontaneous normalization of negative T waves (TWN) on infarct-related ECG leads (IRLs) in the chronic phase of Q wave anterior myocardial infarction (MI) could be a predictor of residual viability in infarct areas. We prospectively studied 35 patients (age 60 +/- 8.6 years) in the chronic phase of Q wave anterior MI. Spontaneous TWN (group A, n = 23) were defined as negative T waves that became upright (> or =0.15 mV) in > or =2 IRLs. The presence of negative T waves (group B, n = 12) was defined as symmetric or biphasic negative T wave of > or =0.15 mV. All patients underwent same-day rest 201Tl-stress (99m)Tc sestamibi dual-isotope myocardial perfusion SPECT and 24-hour 201Tl reinjection imaging for ischemia and viability analysis. On scintigraphic examination, ischemic or viable myocardial segments were found in 18 patients (78%) with TWN and 4 patients (33%) of group B (p = 0.013). The use of TWN as a parameter had a marked influence on the sensitivity (82%), specificity (62%), positive (78%) and negative (67%) predictive values and accuracy (74%) of the diagnosis of viable myocardium. If we add the criterion of positive T waves in aVR with negative T waves to our criteria, we found that sensitivity (90%), positive (80%) and negative (80%) predictive values and accuracy (80%) increased. The results of our study suggest that analysis of TWN on IRLs is an accurate marker of residual viability and/or persistent peri-infarct ischemia in patients in the chronic stage of Q wave anterior MI, and therefore optimizes the diagnostic and therapeutic strategies after MI.