Non-anterior Myocardial Infarction Research Articles

LONG-TERM PROGNOSIS OF THE DEVELOPMENT OF HEART FAILURE WITH LOW EJECTION FRACTION IN ACUTE CORONARY SYNDROME IN YOUNG AND MIDDLE-AGED PATIENTS WITH ARTERIAL HYPERTENSION

Objective: To determine the prognosis and dynamics of the development of heart failure with low ejection fraction (HFrEF) after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) in young and middle-aged patients with arterial hypertension (AH) and type 2 diabetes mellitus (DM) Design and method: The study included 191 hypertensive patients aged 36-59 years with ACS after PCI. Group 1 - 76 patients with hypertension in combination with DM, group 2 - 115 patients with hypertension without DM. In 35 (46%) people of the 1st group and in 56 (48.7%) of the 2nd group, myocardial infarction (MI) of the anterior wall of the left ventricle (LV) was determined. The incidence of non-anterior MI (posterior and lateral walls) of the LV was 54% and 51.3% respectively. Patients in both groups were comparable. Observation was carried out for 12±1 months. Ejection fraction (EF), indices of LV end-systolic volume (LVESVI), LV end-diastolic volumes (LVEDVI), and index of impaired local contractility (ILCI) were determined over time. Results: On the first day after PCI, LVEF <40% (36%, 27-39%) in 14 of 76 (18.4%) in group 1; LVESVI - 43 ml/m2 (40-48 ml/m2); LVEDVI - 77 ml/m2 (67-87 ml/m2); ILCI 1.81 (1.63-2.0). After 12 months, LVEF decreased to 33% (28-39%) in 26 of 76 (34.2%) patients. The progression of HFrEF was indicated by an increase in initial LVESVI by 29-30% and LVEDVI by 23-35%. In group 2, on the first day after myocardial reperfusion in 8 out of 115 (7%) patients, LVEF was 38% (37 - 39%), LVESVI 44 ml/m2 (40-46 ml/m2), LVEDVI 69 ml/m2 m2 (64-76 ml/m2), ILCI 1.75 (1.13-1.88). After 12 months, HFrEF was detected in 10 of 115 (8.7%) patients with an increase in initial LVESVI values by 28%, LVEDVI by 31% and a decrease in LVEF to 36% (35-39%) (p = 0.0242). Conclusions: In young and middle-aged patients with hypertension in combination with DM, during the first 12 months after MI, in 34.2% of cases, there is a significant deterioration in the course of HFrEF, which requires an early decision on the timing of complete myocardial revascularization.

Differences in clinical characteristics and outcomes between patients with left ventricular thrombus following non-anterior and anterior ST-elevation myocardial infarction

Abstract Background Left ventricular thrombus (LVT) is a serious complication following ST-elevation myocardial infarction (STEMI), and occurs more frequently in anterior compared to non-anterior myocardial infarction (MI).1 There is limited data on the clinical characteristics and outcomes in patients with LVT following non-anterior MI. Purpose We aimed to describe the clinical characteristics and outcomes of patients with LVT following non-anterior MI, and compare them against patients with LVT associated with anterior MI. Methods We retrospectively studied 217 consecutive patients with post-STEMI LVT from our tertiary centre’s echocardiography database between March 2011 and January 2021. Trans-thoracic echocardiography was performed at day 2 or 3 post-MI. We compared baseline co-morbidities and echocardiographic parameters between patients with LVT following non-anterior versus anterior MI. The Kaplan Meier method with log-rank test was used to compare rates of thrombus resolution, stroke and all-cause mortality between the 2 groups. Multivariable Cox regression models were constructed to correct for potential confounders. Results Mean age of the study population was 56.0 (IQR 48.0, 63.0) years old and 16/217 (7.4%) were female. LVT following non-anterior MI made up 24/217 patients (11.1%), and included lateral (n=3), inferior (n=15), inferoposterior (n=4) and inferolateral (n=2) MI. Patients with LVT associated with non-anterior MI were older and more frequently had a history of ischaemic heart disease (Figure 1). These patients also had a lower median left ventricular ejection fraction (LVEF) of 29% compared to their counterparts with anterior MI (mean LVEF 38%). Rate of anticoagulation was lower in patients with LVT associated with non-anterior MI (75.0% versus 92.2%). There were no differences in rates of thrombus resolution between the 2 groups (Figure 2). Patients with LVT following non-anterior MI had a higher incidence of stroke, however this observation was not present after correction for baseline embolic risk (CHA2DS2-VASc score) and rate of anticoagulation. Mortality rates were similar in patients with LVT following non-anterior MI versus anterior MI, after correction for baseline co-morbidities as well as in-hospital mortality – as this was more likely due to acute MI complications rather than longer term consequences of LVT. Conclusions Patients with LVT following non-anterior MI are older with a greater prevalence of prior ischaemic heart disease. These patients had a greater rate of stroke and mortality, although baseline co-morbidities and less frequent use of anticoagulation may have contributed to these findings. This needs to be clarified in future prospective studies.Figure 1:Baseline characteristicsFigure 2:Outcomes

The predictive value of relative wall thickness on the prognosis of the patients with ST-segment elevation myocardial infarction

ObjectiveThe study aimed to evaluate the prognostic value of relative wall thickness (RWT) in the patients with ST-segment elevation myocardial infarction (STEMI).MethodsA total of 866 patients with STEMI admitted in Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School from November 2010 to December 2018 were enrolled in the current study retrospectively. Three methods were used to calculate RWT: RWTPW, RWTIVS+PW and RWTIVS. The included patients were divided according to the median values of RWTPW, RWTIVS+PW, and RWTIVS, respectively. Survival analysis were performed with Kaplan–Meier plot and multivariate Cox proportional hazard model was established to evaluate the adjusted hazard ratio of the three kinds of RWT for all cause death, cardiac death and MACE (major adverse cardiac death).ResultsThere was no significance for the survival analysis between the low and high groups of RWTPW, RWTIVS+PW and RWTIVS at 30 days and 12 months. Nonetheless, the cumulative incidence of all cause death and cardiac death in the low group of RWTPW and RWTIVS+PW was higher than those in the high group at 60 months. The cumulative incidence of MACE in the low group of RWTPW was higher than the high group at 60 months. Multivariate Cox regression model showed that RWTPW were inversely associated with long-term cardiac death and MACE in STEMI patients. In the subgroup analysis, three calculations of RWT had no predictive value for the patients with anterior myocardial infarction. By contrast, RWTPW was the most stable independent predictor for the long-term outcomes of the patients with non-anterior myocardial infarction.ConclusionRWTPW, RWTIVS+PW and RWTIVS had no predictive value for the long-term clinical outcomes of patients with anterior myocardial infarction, whereas RWTPW was a reliable predictor for all cause death, cardiac death and MACE in patients with non-anterior myocardial infarction.

Anterior vs non-anterior ST-segment elevation myocardial infarction: incidence of reinfarction and target vessel failure

Abstract Funding Acknowledgements Type of funding sources: None. Background and purpose Left anterior descending (LAD) coronary artery occlusion has been associated with worse short-term outcomes and overall worse prognosis, there is still unclear data about the long-term risk of reinfarction in relation to the index culprit vessel. Methods In this retrospective cohort study, between 2008 and 2013, a total of 584 patients were admitted with STEMI and were subject to emergent percutaneous coronary intervention (PCI). Of those, 535 (91.6%) were alive at hospital discharge, from which 532 were considered for the analysis, after excluding the missing cases. We stratified the individuals according to the culprit vessel in two groups: anterior myocardial infarction (MI) (LAD or left main stem (LM)), and non-anterior MI (circumflex (CX) or right coronary artery (RCA)). We followed the cases for a maximum of 8 years, censoring every event beyond. The primary endpoints were reinfarction and target vessel failure (TVF). Secondary endpoints included all-cause mortality, heart failure (HF) hospitalization and stroke. Mann-Whitney-U and Chi-square tests were used to compare baseline characteristics. Kaplan-Meyer survival analysis was used to obtain the survival curves. Univariate and multivariate analysis were done using Cox regression models. Results Of the 532 individuals included in the analysis, 395 (74.2%) were men and the median age was 61 (+/- 19.8) years. The most common culprit vessel was RCA (45.5%), followed by LAD (41.2%), CX (13.2%), and lastly LM (0.20%). The median follow-up time was 6.94 (+/- 2.38) years. Overall, the anterior MI group presented at a higher Killip class (20.0% vs 14.8% in Killip class II-IV; p = 0.046) and had higher peak plasma level of high-sensitivity troponin T (6.16 vs 3.66 ng/ml; p < 0.001), suggesting larger infarct area. Left ventricle ejection fraction (LVEF) at discharge was also lower in the anterior MI group (reduced in 78,3% vs 43.4%; p < 0.001). Multivessel disease was more common in the non-anterior MI group (49.5% vs 60.9%; p = 0.005), as was PCI of non-culprit vessels (15.5% vs 22.8%; p = 0.037) and the use of bare-metal stents (20.0 vs 51.6%; p < 0.001). There were no significant differences between the groups regarding the main comorbidities, except for peripheral artery disease, more common in the non-anterior MI group (4.10 vs 10.0%; p = 0.011). There was a higher risk of reinfarction in the non-anterior MI group which persisted after relevant variable adjustment (Adjusted hazard ratio 1.96; 95% CI [1.08 – 3.67]; p = 0.027) (Figure 1). There were no significant differences regarding the risk of TVF or any of the secondary outcomes. Conclusions Although LAD/LM occlusion is thought to carry a worse short-term prognosis, non-anterior STEMI appears to be associated with a higher long-term risk of reinfarction. Despite higher rates of reinfarction, non-anterior STEMI patients have not been shown to have an excess mortality of HF hospitalizations in this cohort.

Significance of the N-terminal Fragment of Brain Natriuretic Peptides in Predicting Ventricular Arrhythmias in Young and Middle-Aged Patients with Diabetes and Myocardial Infarction

ABSTRACT. Fatal ventricular arrhythmias in patients with diabetes mellitus (DM) in the acute stage of myocardial infarction (MI) and postinfarction period often cause adverse outcomes. Therefore, the search for new reliable biomarkers in predicting ventricular arrhythmias in the long term is necessary.
 AIM: This study aimed to evaluate the value of N-terminal-pro hormone BNP (NT-proBNP) in predicting ventricular arrhythmias in young and middle-aged patients with MI and DM-associated ST-segment elevation.
 MATERIALS AND METHODS: Seventy-six patients (59 men and 17 women) with DM and MI with ST-segment elevation (aged 3659 years; mean 53 5 years) were examined. Anterior MI was diagnosed in 35 patients, and non-anterior MI was detected in 41 patients. The DM duration was up to 1 year in 16 patients, 15 years in 24, and 512 years in 36. Patients were examined on day 1 after percutaneous coronary intervention (PCI) with implantation of 13 stents in the coronary arteries (CA) and again after 12 months. Holter monitoring, echocardiography, and blood tests for NT-proBNP were performed.
 RESULTS: After PCI, ventricular extrasystole (VES) of grades IIIV according to Lown and Wolf was detected in 21 of 37 (56.7%) patients with DM. The left ventricular ejection fraction (LVEF) was 42% (27%45%), and the NT-proBNP level was 1127 (7902530) at a rate of up to 125 pg/mL. After 12 months, VES was noted in 9 of 37 (24.3%) patients. The LVEF was 33% (28%35%), and the NT-proBNP level was 938 (4971294) pg/mL. A positive correlation was found between the blood serum level of NT-proBNP on day 1 after PCI and the number of grade IIIV VES 12 months later. At an NT-proBNP level of 898 pg/mL on day 1 after PCI, the sensitivity of this biomarker in predicting high-grade VES 12 months after MI in patients with DM was 100%.
 CONCLUSIONS: The NT-proBNP level after PCI in patients with DM and MI is a reliable predictor of ventricular arrhythmias over the next 12 months.

Effect of Infarct Location and Size on Left Atrial Function: A Cardiovascular Magnetic Resonance Feature Tracking Study.

Background: LA function has been recognized as a significant prognostic marker in many cardiovascular diseases. Cardiovascular magnetic resonance feature tracking (CMR-FT) represents a promising technique for left atrial function evaluation. The size and location of myocardial infarction are important factors in the cause of adverse left ventricular remodeling, but the effect on the left atriam is unclear. Purpose: to investigate the effect of location and size of previous myocardial infarction (MI) on LA function using CMR-FT. Study type: retrospective. Population: patients formerly diagnosed with anterior MI (n = 42) or non-anterior MI (n = 40) and healthy controls (n = 47). Field Strength/Sequence: a 3.0T MR, Steady state free precession (SSFP), Phase-sensitive inversion recovery (PSIR). Assessment: infarct location and size were assigned and quantified by late-gadolinium enhancement (LGE) imaging. LA performance was analyzed using CMR-FT in 2- and 4-chamber cine images, including LA reservoir, conduit and booster pump function. Statistics: descriptive statistics, ANOVA with post Bonferroni correction, Kruskal−Wallis H, Spearman’s correlation, intraclass correlation coefficient. Results: Anterior MI patients had impaired LA reservoir function (LATEF, εs, SRs), conduit function (LAPEF, εe, SRs) and booster pump function (LAAEF, εa) compared with controls (p < 0.05). Non-anterior MI patients had impaired LA strain (εs, εe, εa; p < 0.05) but preserved LAEFs (p > 0.05). After adjusting the area of MI, there was no significant difference in the LA morphology and function between the anterior and non-anterior wall groups. Stratification analysis by MI size revealed that LA volumes and LAEFs were unchanged in patients with MI size ≤ 15% compared with controls (p > 0.05); only εs and εe were decreased (p < 0.05). Increased LAVIpre-a, LAVImin and decreased LATEF, and LAAEF were found in patients with MI size > 15% compared with the MI size ≤ 15% group (p < 0.05). LVSVI, εs and MI size were significant correlated with LAVI pre-a in multiple stepwise regression analysis. Data conclusions: The location of myocardial infarction is not a major factor affecting the morphology and function of the left atrium. Patients with MI size > 15% experience more pronounced post-infarction LA remodeling and dysfunction than MI size ≤ 15% patients.

Clinical Characteristics and Short-Term Outcomes of Patients Presenting with Acute Myocardial Infarction having Multi-vessel disease - A Single Middle- eastern Tertiary-Care Center Experience

ObjectivePatients with multi-vessel coronary artery disease (MVD) compared to single-vessel coronary artery disease (CAD) have more comorbidities and poor in-hospital outcomes. We aim to analyze MVD-AMI patients regarding clinical data and short-term outcomes. MethodsThis is a retrospective analysis of the prospectively collected data registry, a single-center study reviewing the clinical details and hospital outcome measures of AMI patients referred to our center for early revascularization from 2016 to 2019. ResultOut of 3041 patients presented with AMI, 491 (16%) had MVD on coronary angiogram. MVD-AMI patients were older, had a higher prevalence of DM, HTN, and prior history of ischemic heart disease compared to the non- MVD -AMI group (p < 0.001 for all). However, they presented more with non-anterior myocardial infarction, showed higher rates of post-myocardial infarction LV dysfunction, and mortality (p < 0.001). Older MVD-AMI patients showed higher rates of in-hospital morbidities and mortality compared to younger ones (p < 0.001). MVD- AMI women and Middle Eastern patients were older and showed a higher prevalence of cardiovascular risk factors compared to MVD-AMI men and South Asian patient population respectively. There were no significant differences recorded among the different subgroups of MVD-AMI patients regarding the hospital outcome measures. ConclusionOur study highlighted the clinical characters and poor outcomes of a high-risk group of MVD-AMI with different demographic backgrounds. Although age was a strong predictor for in-hospital poor outcomes, neither gender nor ethnicity affected the outcomes in them.

Abstract 13780: Aggressive Hydration and Contrast-Induced Acute Kidney Injury Following Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction: A Randomized Controlled Study

Objective: To evaluate the efficacy of aggressive hydration compared with general hydration for contrast induced acute kidney injury (CI-AKI) prevention among patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). Methods: The ATTEMPT study is an open-label, randomized controlled study at 15 teaching hospitals in China. A total of 560 adult patients were randomly assigned (1:1) to receive aggressive hydration or general hydration treatment. Aggressive hydration group received preprocedural loading dose of 125/250 mL normal saline within 30 minutes, followed by postprocedural hydration performed for 4 hours under left ventricular end-diastolic pressure guidance and additional hydration until 24 hours after pPCI. General hydration group received ≤500 mL 0.9% saline at 1 mL/kg/h for 6 hours after randomization. The primary endpoint is CI-AKI, defined as a &gt;25% or 0.5 mg/dL increased in serum creatinine from baseline during the first 48-72 hours after primary angioplasty. The safety endpoint is hydration relative acute heart failure. Results: From July 2014 and May 2018, 469 patients were enrolled in the final analysis. CI-AKI occurred less frequently in aggressive hydration group than in general hydration group (21.8% vs. 31.1%; RR 0.78, 95% CI 0.61 to 0.98). Hydration relative acute heart failure did not significantly differ between the aggressive hydration group and the general hydration group (7.9% vs. 6.9%, RR 1.07, 95% CI 0.77 to 1.48). Several subgroup analysis showed the better effect of aggressive hydration in CI-AKI prevention in male, renal insufficient and non-anterior myocardial infarction participants. Conclusions: Comparing with general hydration, the peri-operative aggressive hydration seems to be safe and effective in preventing CI-AKI among patients with STEMI undergoing pPCI.

Hydration for prevention of kidney injury after primary coronary intervention for acute myocardial infarction: a randomised clinical trial

ObjectiveTo evaluate the efficacy of aggressive hydration compared with general hydration for contrast-induced acute kidney injury (CI-AKI) prevention among patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention...

Comparison of Left Ventricular Global Strain in Anterior and Non-anterior Wall Myocardial Infarction With CMR Tissue Tracking.

Left ventricular (LV) myocardial dysfunction occurs after myocardial infarction (MI) is associated with the location, infarct size, and transmurality degrees of MI. The myocardial strain is a sensitive index used for the quantification of myocardium dysfunction. This study used Tissue-Tracking to evaluate whether the different location of MI would result in different myocardial dysfunction. One hundred patients diagnosed with MI who underwent cardiovascular magnetic resonance examination were included. The tissue-tracking indices, LV global radial strain (GRS), global circumferential strain (GCS), global longitudinal strain (GLS), and the infarct size (IS,% of LV mass) were quantified. There were 42 cases of anterior wall MI (AWMI) and 58 cases of non-anterior wall MI (NAWMI). The GCS of AWMI was significantly lower than that of NAWMI (P = 0.036). In the same level of infarct size, the myocardial strain of AWMI was not significantly different from NAWMI group (P > 0.05). The GRS and GCS were significantly different between transmurality > 50% group with transmurality ≤ 50% group (P < 0.05). The present study demonstrated that LV MI is associated with reduced myocardial strain, and the infarct size and degrees of transmurality were both related to the decline of myocardial strain in patients with MI.

Adjuvant Therapy for Acute Myocardial Infarction: Differential Outcomes with Edetate Disodium-Based Treatment Among Stable Post-Anterior vs. Non-Anterior Myocardial Infarction Patients

Adjuvant Therapy for Acute Myocardial Infarction: Differential Outcomes with Edetate Disodium-Based Treatment Among Stable Post-Anterior vs. Non-Anterior Myocardial Infarction Patients

Differential Outcomes With Edetate Disodium-Based Treatment Among Stable Post Anterior vs. Non-Anterior Myocardial Infarction Patients

BackgroundThe Trial to Assess Chelation Therapy (TACT) found that chelation therapy significantly reduced clinical events in patients with a history of myocardial infarction (MI). The initial report of TACT included the observation of an interaction between edetate disodium infusions and MI location, as well as diabetes. Thus, we examined in greater detail the effect of edetate disodium chelation therapy as a function of MI location and diabetes. MethodsPatients (n = 1708) at least 6 weeks post-MI and age ≥ 50 were randomized to receive 40 infusions of a 500 mL chelation solution or placebo (median follow-up 55 months). The effect of edetate disodium on the primary outcome (all-cause mortality, MI, stroke, hospitalization for angina, or coronary revascularization) was assessed as a function of MI location using log-rank test and Cox regression model, adjusting for other prognostic variables. ResultsAmong patients with post anterior MI (n = 674), chelation was associated with a lower risk of the primary endpoint (HR 0.63, 95% CI 0.47–0.86, p = 0.003) among anterior MI patients, but not in post non-anterior MI (n = 1034) patients (HR 0.96, 95% CI 0.77–1.20, p = 0.702) (p-for-interaction = 0.032). The point estimates for each component of the primary endpoint favored chelation therapy. The differing treatment effect in patients with post anterior vs. non-anterior MI was consistent among patients with or without diabetes and remained significant after adjusting for other prognostic variables (p < 0.01). ConclusionsEdetate disodium infusions reduced the risk of cardiovascular events among patients with a prior anterior MI. Future studies should focus on replicating these results and understanding the mechanisms of benefit.

Native T1 value in the remote myocardium is independently associated with left ventricular dysfunction in patients with prior myocardial infarction.

To compare remote myocardium native T1 in patients with chronic myocardial infarction (MI) and controls without MI and to elucidate the relationship of infarct size and native T1 in the remote myocardium for the prediction of left ventricular (LV) systolic dysfunction after MI. A total of 41 chronic MI (18 anterior MI) patients and 15 age-matched volunteers with normal LV systolic function and no history of MI underwent cardiac magnetic resonance imaging (MRI) at 1.5T. Native T1 map was performed using a slice interleaved T1 mapping and late gadolinium enhancement (LGE) imaging. Cine MR was acquired to assess LV function and mass. The remote myocardium native T1 time was significantly elevated in patients with prior MI, compared to controls, for both anterior MI and nonanterior MI (anterior MI: 1099 ± 30, nonanterior MI: 1097 ± 39, controls: 1068 ± 25 msec, P < 0.05). Remote myocardium native T1 moderately correlated with LV volume, mass index, and ejection fraction (r = 0.38, 0.50, -0.49, respectively, all P < 0.05). LGE infarct size had a moderate correlation with reduced LV ejection fraction (r = -0.33, P < 0.05), but there was no significant association between native T1 and infarct size. Native T1 time in the remote myocardium was independently associated with reduced LV ejection fraction, after adjusting for age, gender, infarct size, and comorbidity (β = -0.34, P = 0.03). In chronic MI, the severity of LV systolic dysfunction after MI is independently associated with native T1 in the remote myocardium. Diffuse myocardial fibrosis in the remote myocardium may play an important pathophysiological role of post-MI LV dysfunction. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1073-1081.

Difference in the Prognostic Impact of Left Ventricular Global Longitudinal Strain between Anterior and Nonanterior Myocardial Infarction.

Speckle tracking-derived global longitudinal strain (GLS) of left ventricle is a potent prognostic marker for patients with ST-segment elevation myocardial infarction (STEMI). The purpose of this study was to investigate the difference of prognostic impact of GLS between anterior and nonanterior myocardial infarction. This study included 686 patients who underwent primary percutaneous coronary intervention for their first STEMI between November 2007 and April 2012. Differences in the prognostic impact of GLS between anterior MI group and nonanterior MI group were evaluated. The composite of all-cause mortality and hospitalization for heart failure in 2 years was investigated for outcome. During the follow-up period, 77 (11.2%) adverse events occurred. The anterior and nonanterior MI groups included 339 and 347 patients, respectively. Among patients with anterior MI, GLS significantly predicted 2-year outcome in an adjusted model (adjusted hazard ratio [HR] 1.186; 95% confidence interval [CI] 1.071-1.314, P = 0.001), whereas the association between GLS and mortality was weaker in the nonanterior MI group (adjusted HR 0.977; 95% CI 0.884-1.081, P = 0.657). The interaction between the infarction territory and GLS was significant (P for interaction = 0.018), indicating that GLS was a more sensitive predictor of mortality in patients with anterior MI than that in those with nonanterior MI. Speckle tracking-derived GLS of left ventricle more sensitively predicted clinical outcome in patients with anterior MI than in those with nonanterior MI.

Peri-infarct zone pacing to prevent adverse left ventricular remodelling in patients with large myocardial infarction.

We sought to determine whether peri-infarct pacing prevents left ventricular (LV) remodelling and improves functional and clinical outcomes in patients with large first myocardial infarction (MI). A total of 126 patients at 27 international sites within 10 days of onset of anterior or non-anterior MI with creatine phosphokinase >3000 U/L and QRS duration ≤120 ms were randomized 1:1:1 to dual-site biventricular pacing vs. single-site LV only pacing vs. non-implanted control. The primary endpoint was the echocardiographic core laboratory-assessed change in LV end-diastolic volume (ΔLVEDV) from baseline to 18 months between the pooled pacing therapy groups and the control group. ΔLVEDV increased by 15.3 ± 28.6 mL in the control group and by 16.7 ± 30.5 mL in the pooled pacing groups during follow-up (adjusted mean difference (95% CI) = 0.6 (-12.3, 13.5) mL, P = 0.92). There were also no significant between-group differences in the change in LV end-systolic volume or ejection fraction over time. Quality of life, as assessed by the Minnesota Living with Heart Failure (HF) and European Quality of Life-5 Dimension questionnaires and New York Heart Association class, was also similar between groups during 18-month follow-up. Six-minute walk distance improved during follow-up to an equal degree between groups, and there were no significant differences in the 18-month rates of death or HF hospitalization between the pooled pacing therapy vs. control groups (17.4 vs. 21.7% respectively, P = 0.59). In the present multicentre, randomized trial, peri-infarct pacing did not prevent LV remodelling or improve functional or clinical outcomes during 18-month follow-up in patients with large first MI. NCT01213251.

The influence of system delay on 30-day and on long-term mortality in patients with anterior versus non-anterior ST-segment elevation myocardial infarction: a cohort study

AimTo evaluate the relationship between system delay and 30-day and long-term mortality in patients with anterior versus non-anterior ST-elevation myocardial infarction (STEMI).MethodsWe conducted a prospective observational cohort study. Patients with...

Electrocardiographic prediction of lateral involvement in acute non-anterior wall myocardial infarction

PurposeRecent research has established that a tall R-wave in V1 indicates lateral wall involvement in non-anterior wall myocardial infarction (MI). The objective of this study was to assess the value of the admission electrocardiogram (ECG) to predict R-waves and consequently lateral wall damage in the late phase of non-anterior MI. MethodsECGs of 69 patients were analyzed. ST-segment changes in representative leads for lateral wall infarction such as V1, V2, V6 and I were correlated with the extent of QRS-wave changes in V1 and V6. ResultsST-segment elevation in V6 showed correlations with R/S ratio in V1 (r=0.802, B=0.440, P=<0.001) and with the depth of Q-waves in V6 (r=0.671, B=0.441, P=0.007). This correlation was higher in a small subgroup where the left circumflex branch (Cx) was the culprit vessel (r=0.888, B=1.469 and P=0.018). ST-segment depression in lead I correlated with the height of R and the surface of R in V1 (height times width of R) (r=0.542, B=−0.150, P=0.005 and r=0.538, B=−0.153, P=0.005 respectively), especially in the subgroup without proximal occlusions of RCA (r=0.711 and r=0.699). ST-segment depression in lead I also predicted Q-waves in V6 (r=0.538, B=0.114, P=0.006). ST-segment changes in V2 showed no significant correlation with either R- or Q-wave measurements. ConclusionsST-segment elevation in V6 in the acute phase of non-anterior MI predicts lateral involvement as expressed by the R/S ratio in V1 in the post reperfusion phase. A subgroup with Cx occlusion showed especially strong correlations, although the size of the group was small. In lead I ST-segment depression is correlated to height and surface of R in V1 and Q-waves in V6.

Evaluation of the electrocardiogram in identifying and quantifying lateral involvement in nonanterior wall infarction using cardiovascular magnetic resonance imaging

PurposeThe objective of this study was to assess the involvement and extent of lateral wall myocardial infarction (MI) in patients with a first nonanterior wall MI, as reflected by changes in precordial leads. Delayed enhancement cardiac magnetic resonance imaging was used as a gold standard to localize and quantify myocardial scar tissue. MethodsElectrocardiogram and cardiac magnetic resonance were studied in 56 patients. Areas involved were related to QRS changes in precordial leads. ResultsSignificant correlations were found between lateral wall involvement and R waves in V1 and V6 (P = 0.009-0.022). For patients with circumflex branch occlusions, the MI size of the apical and lateral segments correlated strongly with the characteristics of R waves in V1 and V2 (P = 0.001-0.034). ConclusionsTall and broad R waves in V1 reflect lateral wall MI, especially in circumflex occlusions.

Relationship between location and size of myocardial infarction and their reciprocal influences on post-infarction left ventricular remodelling

To assess the intricate relationship between myocardial infarction (MI) location and size and their reciprocal influences on post-infarction left ventricular (LV) remodelling. A cohort of 260 reperfused ST-segment elevation MI patients was prospectively studied with cardiovascular magnetic resonance at 1 week (baseline) and 4 months (follow-up). Area at risk (AAR) and MI size were quantified by T2-weighted and late-gadolinium enhancement imaging, respectively. Adverse LV remodelling was defined as an increase in LV end-systolic volume ≥15% at follow-up. One hundred and twenty-seven (49%) patients had anterior MI and 133 (51%) patients had non-anterior MI. Although the degree of myocardial salvage was similar between groups (P = 0.74), anterior MI patients had larger AAR and MI size than non-anterior MI patients yielding worse regional and global LV function at baseline and follow-up. At univariable analysis, anterior MI was associated with increased risk of adverse LV remodelling (P = 0.017) and lower LV ejection fraction (EF) at follow-up (P = 0.001), but not when accounted for baseline MI size. Accordingly, at multivariable analysis, baseline MI size but not its location was an independent predictor of adverse LV remodelling (odds ratio = 1.061, P < 0.001) and EF at follow-up (β-coefficient = -0.255, P < 0.001). Anterior MI patients experience more pronounced post-infarction LV remodelling and dysfunction than non-anterior MI patients due to a greater magnitude of irreversible ischaemic LV damage without any independent contribution of MI location.

Relationship between location and size of myocardial infarction and their reciprocal influences on post-infarction left ventricular remodeling

Background Patients with anterior MI experience worse LV remodeling and dysfunction than non-anterior MI patients. It remains unclear whether this difference is due to larger MI size or whether infarct location plays a role beyond MI size. Study aim To assess the relationship between myocardial infarction (MI) location and size and their reciprocal influences on post-infarction left ventricular (LV) remodeling. Methods A cohort of 260 reperfused ST-segment elevation MI patients was studied with cardiovascular magnetic resonance (CMR) at 1-week (baseline) and 4-month (followup). Area at risk (AAR) and MI size were quantified by T2-weighted and late gadolinium enhancement imaging, respectively. Adverse LV remodeling was defined as increase in LV end-systolic volume ≥15% at follow-up. Results One-hundred twenty-seven(49%) patients had anterior MI and 133(51%) patients had non-anterior MI. Although the degree of myocardial salvage was similar between groups (p=0.74), anterior MI patients had larger AAR and MI size than non-anterior MI patients yielding worse regional and global LV function at baseline and follow-up. At univariable analysis, anterior MI was associated with increased risk of adverse LV remodeling (p=0.017) and lower LV ejection-fraction at follow-up (p=0.001), but not when accounted for baseline MI size. Accordingly, at multivariable analysis baseline MI size but not its location was an independent predictor of adverse LV remodeling (OR=1.061, p<0.001) and ejection-fraction at follow-up (Beta-coefficient=-0.255, p<0.001).