Prognostic impact of bundle branch block after acute coronary syndrome. Does it matter if it is left of right?

The ratio of QRS/RV6-V1: a new electrocardiographic predictor of short- and long-term adverse clinical outcomes in patients with acute myocardial infarction combined with new-onset right bundle branch block

Background

A few studies have focused on electrocardiography (ECG) parameters correlating with clinical prognosis in patients with acute myocardial infarction (AMI) combined with new-onset right bundle branch block (RBBB).

Objective

To assess the prognostic value of a new ECG parameter, namely, the ratio of QRS duration/RV₆-V₁ interval (QRS/RV₆-V₁), in patients with AMI combined with new-onset RBBB.

Materials and methods

A total of 272 AMI patients combined with new-onset RBBB who received primary percutaneous coronary intervention (P-PCI) were retrospectively enrolled in the study. First, the patients were divided into survival group and non-survival group. Demographic, angiographic, and ECG characteristics were compared between the two groups. Receiver operating characteristic (ROC) curve was used to screen the best ECG parameter for predicting 1-year mortality. Second, the ratio of QRS/RV₆-V₁, a continuous variable, was converted to the high ratio group and low ratio group according to the optimal cutoff value point determined by the X-tile software. We compared the patient's demographic, angiographic, and ECG characteristics, in-hospital major adverse cardiovascular events (MACE), and 1-year mortality between the two groups. Multivariate logistic and Cox regressions were used to evaluate whether the ratio of QRS/RV₆-V₁ was an independent prognostic factor of in-hospital MACE and 1-year mortality.

Results

The ROC curve showed that the ratio of QRS/RV₆-V₁ had a higher value for predicting in-hospital MACE and 1-year mortality than the QRS duration, RV₆-V₁ interval, and RV₁ interval. The patients in the high ratio group had significantly higher CK-MB peak and Killip class, lower ejection fraction (EF%), higher ratio of the left anterior (LAD) descending artery as infarct-related artery (IRA), and longer total ischemia time (TIT) than those in the low ratio group. The QRS duration was wider in the high ratio group than that in the low ratio group, whereas RV₆-V₁ was narrower in the high ratio group compared with that in the low ratio group. The in-hospital MACE rate (93.3% vs. 31.0%, p < 0.001) and 1-year mortality rate (86.7% vs. 13.2%, p < 0.001) in the high ratio group were higher than those in the low ratio group. The higher ratio of QRS/RV₆-V₁ was an independent predictor of in-hospital MACE (odds ratio, 8.55; 95% CI, 1.40-52.37; p = 0.02) after adjusting other confounders. Cox regression showed that the higher ratio of QRS/RV₆-V₁ predicted higher 1-year mortality of the patients with AMI combined with new-onset RBBB [hazard ratios (HR), 12.4; 95% CI, 7.26-21.22); p < 0.001] than the lower ratio of QRS/RV₆-V₁, and the HR still stayed at 2.21 even after a multivariable adjustment (HR, 2.21; 95% CI, 1.05-4.64); p = 0.037).

Conclusion

According to the results of our study, the high ratio of QRS/RV₆-V₁ (>3.0) was a valuable predictor of short- and long-term adverse clinical outcomes in AMI patients combined with new-onset RBBB. The implications of the high ratio of QRS/RV₆-V₁ were severe ischemia and pseudo synchronization between bi-ventricle.

The Relationship of Conduction Disorder and Prognosis in Patients with Acute Coronary Syndrome

OBJECTIVE

Conduction disorders with a widened QRS are associated with poor prognosis in patients with acute coronary syndrome (ACS). Conduction disorders include left bundle branch block (LBBB), right bundle branch block (RBBB), and nonspecific intraventricular conduction delay (NICD). Previous studies did not have conflicting results regarding the type of bundle branch block (BBB) with the worst prognosis, and few studies have focused on the prognosis of patients with NICD.

METHODS

Patients with ACS were enrolled between January 2005 and December 2019, and their medical history (International Classification of Diseases codes) was obtained from the Chang Gung Research Database. Age, sex, comorbidities, left ventricular ejection fraction (LVEF), and drug use were compared between the patients with and without conduction disorders. The following clinical outcomes were compared between patients with and without conduction disorders: heart failure (HF) hospitalization, cardiovascular (CV) mortality, and all-cause mortality. After propensity score matching, the Kaplan-Meier curve analysis for HF hospitalization, CV mortality, and all-cause mortality were compared among patients with LBBB, RBBB, and NICD.

RESULTS

This study enrolled a total of 33970 participants and involved 3392 and 30578 patients with and without conduction disorders, respectively. Older age and a higher prevalence of comorbidities were noted in patients with conduction disorders. Lower mean LVEF was exhibited in the patients with conduction disorders (with vs. without; 44.64 ± 20.73% vs. 49.85 ± 20.63%; p < 0.001). During the 3-year follow-up period, higher incidences of HF hospitalization (21.55% vs. 17.51%; p < 0.001), CV mortality (17.98% vs. 12.14%; p < 0.001), and all-cause mortality (38.86% vs. 31.15%; p < 0.001) were noted in the patients with conduction disorder. After ACS events, 10.0% of patients presented with conduction disorders, with LBBB in 3.3%, RBBB in 6.0%, and NICD in 0.7%. The lowest mean of LVEF was presented in the patients with NICD (LBBB vs. RBBB vs. NICD; 41.00 ± 19.47% vs. 47.73 ± 20.82% vs. 34.57 ± 20.02%; p < 0.001). Among the three groups, the highest incidence of HF hospitalization was noted in patients with LBBB after propensity score matching. The lowest incidence of CV and all-cause mortality was observed in patients with RBBB. After adjustment of age, gender, comorbidities, medication, and mean LVEF, those with LBBB had the highest hazard ratio for major adverse cardiovascular events (MACEs) of 1.113 (p=0.029; 95% CI = 1.013-1.266).

CONCLUSIONS

In the ACS population, patients with conduction delay had a poor prognosis due to a higher prevalence of comorbidities and lower mean LVEF. Among the patients with LBBB, RBBB, and NICD, those with LBBB and NICD had a higher incidence of HF hospitalization, CV mortality, and all-cause mortality. Patients with NICD had the lowest mean LVEF compared to those with LBBB and RBBB. Patients with LBBB had a significantly highest HR of MACE.

Prognostic impact of bundle branch blocks in patients with ST-segment elevation myocardial infarction

BACKGROUND

In this study we aim to determine and compare short term outcomes of all type bundle branch blocks (BBB) according to their onset time among those patients presented with ST-Segment elevation myocardial infarction (STEMI) and underwent primary percutaneous coronary intervention (pPCI).

METHOD

Three thousand fifty-seven ST-segment elevation myocardial infarction patients who underwent pPCI were retrospectively evaluated. Those patients with BBB in their ECG on admission were re-evaluated for their prior ECG records. A composite of death, recurrent myocardial infarction (re-MI) and stroke in one moth follow up were defined as major adverse cardiovascular events (MACE).

RESULTS

Three thousand fifty-seven STEMI patients underwent pPCI were enrolled to the study. Among these patients 134 (4.4%) had LBBB, and 120 (3.9%) had RBBB. Bundle brunch block was classified according to the timing of their onset as follows; New or Presumably New BBB, Old BBB, Indeterminate Onset BBB. At one month, 4.8% of the patients died, 2.6% had re-MI/stent thrombosis, 0.5% had stroke. MACE occurred in 7.6% of patients. Left ventricle ejection fraction, BBB, estimated glomerular filtration rate (eGFR), shock and age were ranked as the strongest predictors of MACE. Compared to non-BBB, all BBBs except for old RBBB was found to be associated with increased MACE. New onset LBBB was the strongest predictor (OR:13.1, 95%CI:3.98-43.4, p < .001) at one month MACE.

CONCLUSION

Compared to non-BBB, all BBBs except for old RBBB was found to be associated with increased MACE. New onset LBBB was the strongest predictor for MACE at one month.

Revascularization Strategies in Patients with Acute Myocardial Infarction and Cardiogenic Shock: Results from the Portuguese Registry on Acute Coronary Syndromes

Fundamento:

Em doentes com infarto agudo do miocárdio (IAM), choque cardiogênico (CC) e doença multivaso (DMV) persistem dúvidas sobre a intervenção nas artérias não responsáveis.

Objetivos:

1) caracterizar a amostra de doentes com IAM, CC e DMV incluídos no Registo Nacional Português de Síndromes Coronárias Agudas (RNSCA); 2) comparar os eventos associados a diferentes estratégias de revascularização; e 3) identificar preditores de mortalidade intra-hospitalar nesta amostra.

Métodos:

Estudo observacional retrospetivo de doentes com IAM, CC e DMV incluídos no RNSCA entre 2010 e 2018. Compararam-se duas estratégias de revascularização: completa durante o procedimento índice (grupo 1); e completa diferida ou incompleta durante o internamento (grupo 2-3). O endpoint primário foi a ocorrência de reinfarto ou morte intra-hospitalar. A significância estatística foi definida por um valor p < 0,05.

Resultados:

Identificaram-se 127 doentes com IAM, CC e DMV (18,1% no grupo 1 e 81,9% no grupo 2-3), com idade média de 70 ± 12 anos e 92,9% com IAM com supradesnivelamento do segmento ST. O endpoint primário ocorreu em 47,8% dos doentes do grupo 1 e em 37,5% do grupo 2-3 (p = 0,359). As taxas de mortalidade intra-hospitalar, reinfarto, acidente vascular cerebral e hemorragia major foram também semelhantes nos dois grupos. Os preditores de mortalidade intra-hospitalar nesta amostra foram a presença na admissão de disfunção ventricular esquerda (OR 16,8), bloqueio completo de ramo direito (OR 7,6) e anemia (OR 5,2), (p ≤ 0,02).

Conclusões:

Entre os doentes com IAM, CC e DMV, incluídos no RNSCA, não se verificou diferença significativa entre revascularização completa no evento índex e completa diferida ou incompleta durante o internamento, relativamente à ocorrência de morte intra-hospitalar ou reinfarto. (Arq Bras Cardiol. 2021; 116(5):867-876)

[High-risk ECGs in acute chest pain : Signs of acute ischemia beyond STEMI]

BACKGROUND

Obtaining an electrocardiogram (ECG) is the gold standard for initial diagnostics of atraumatic chest pain. To provide optimal patient care, the treating physician has to be proficient in recognizing early signs of myocardial ischemia. Information from the clinical assessment and typical ECG signs have to be recognized promptly in order to diagnose myocardial ischemia early.

METHODS

A selective literature search in international databases (PubMed, Cochrane Library, Google Scholar) was conducted; current, topic-specific websites and literature were also included and evaluated.

RESULTS

Several subtle ECG abnormalities exist besides the typical ST-elevation myocardial infarction (STEMI) and well-known STEMI equivalents and may point to possible myocardial ischemia.

DISCUSSION

To fully evaluate the ECG in patients with atraumatic chest pain, typical signs of ischemia like STEMI as well as subtle ECG signs should be recognized to allow early cardiac intervention.

Evaluating Mortality Rate and Associated Parameters in Patients with Acute Coronary Syndrome

BACKGROUND

Acute coronary syndrome (ACS) is one of the leading causes of mortality worldwide and is characterized by unstable angina or acute myocardial infarction. The aim of this study is to evaluate the clinical characteristics of patients who died of ACS.

METHODS

In this cross-sectional study, 1000 patients presenting ACS were included. Data and records of these patients were evaluated for parameters such as; deceased status, age, gender, diagnosis, ECG, common complaints, associated risk factors, Killip class, pulse, blood pressure, geographic setup (urban or rural), complications and season in which the disease was presented. Statistical analysis was performed on the data obtained using SPSS-win software.

RESULTS

The mortality rate among ACS patients in our study was 7.1%. Of these patients, AMI was the most prevalent diagnosis and chest pain was the most common complaint. Furthermore, low blood pressure, advanced age, increased pulse rate and fall/winter season were associated with the increased risk of mortality. ST deviation was the most seen ECG finding and most of the mortalities were within the 24 hours of admission.

CONCLUSION

Our study reports risk factors associated with mortality in ACS patients. Advanced and timely therapeutic measurements are likely to reduce the incidence of mortality in these patients.

Clinical Characteristics, Management Strategies, and In-Hospital Outcomes of Acute Coronary Syndrome in a Low Socioeconomic Status Cohort: An Observational Study From Urban India

Background:

Coronary artery disease is the leading cause of mortality in India. There is scarcity of data on demographic profile and outcomes of acute coronary syndrome (ACS) in low socioeconomic status (SES) population of India.

Objectives:

This study was undertaken to determine the clinical presentation, management strategies, and in-hospital outcomes of ACS in low SES population.

Methods:

We conducted 1-year prospective observational cohort study of ACS patients admitted at Employees State Insurance Corporation unit of our tertiary care cardiac center. Clinical parameters, management strategies, and in-hospital outcomes of 621 patients enrolled during the study period from February 2015 to January 2016 were studied.

Results:

Mean age of patients was 56.06 ± 11.29 years. Majority (62%) of the patients had ST elevation myocardial infarction (STEMI), whereas Non-ST elevation acute coronary syndrome (NSTE-ACS) was seen in 38% of the patients. Median time from symptom onset to hospital admission was 285 min with wide range from 105 to 1765 min. Coronary angiography was performed in 81% of patient population. Single-vessel disease (SVD) was the most common pattern (seen in 43.3%) of coronary artery involvement with left anterior descending coronary artery (LAD) being the most frequently involved vessel (62.8%). Pharmaco-invasive approach was the preferred strategy. Overall percutaneous coronary intervention (PCI) rates were 59.1% (62.1% in STEMI and 54.2% in NSTE-ACS). Overall in-hospital mortality was 3.2%, being significantly higher in STEMI (4.2%) as compared with NSTE-ACS (1.7%).

Conclusions:

With implementation of evidence-based pharmacotherapy and interventions, outcomes comparable with developed countries can be achieved even in low SES populations of developing world.