Coronary Disease: Acute myocardial infarction: failed thrombolysis

Mortality outcomes and predictors of failed thrombolysis following STEMI thrombolysis in a non-PCI capable tertiary hospital: a 5-year analysis

Pharmacological reperfusion remains the primary strategy for ST-elevation myocardial infarction (STEMI) in low- and medium-income countries. Literature has reported inconsistent incidences and outcomes of failed thrombolysis (FT). This study aimed to identify the incidence, mortality outcomes and predictors of FT in STEMI pharmacological reperfusion. This single-centre retrospective cohort study analyzed data on consecutive STEMI patients who received thrombolytic therapy from 2016 to 2020 in a public tertiary hospital. Total population sampling was used in this study. Logistic regression analyses were used to assess independent predictors of the mortality outcomes and FT. We analyzed 941 patients with a mean age of 53.0 ± 12.2 years who were predominantly male (n = 846, 89.9%). The in-hospital mortality was 10.3% (n = 97). FT occurred in 86 (9.1%) patients and was one of the predictors of mortality (aOR 3.847, p < 0.001). Overall, tenecteplase use (aOR 1.749, p = 0.021), pre-existing hypertension (aOR 1.730, p = 0.024), history of stroke (aOR 4.176, p = 0.004), and heart rate ≥ 100 bpm at presentation (aOR 2.333, p < 0.001) were the general predictors of FT. The predictors of FT with streptokinase were Killip class ≥ II (aOR 3.197, p = 0.004) and heart rate ≥ 100 bpm at presentation (aOR 3.536, p = 0.001). History of stroke (aOR 6.144, p = 0.004) and heart rate ≥ 100 bpm at presentation (aOR 2.216, p = 0.015) were the predictors of FT in STEMI patients who received tenecteplase. Mortality following STEMI thrombolysis remained high in our population and was attributed to FT. Identified predictors of FT enable early risk stratification to evaluate the patients' prognosis to manage them better.

Evaluation of the tolerability and effectiveness of Tenecteplase in patients with ST-Segment-Elevation Myocardial Infarction in a Secondary Hospital in Malaysia: A Retrospective Case Series

Background

In Malaysia, knowledge regarding the clinical efficacy of tenecteplase (TNK), a fibrin-specific tissue-plasminogen activator, is limited.

Objectives

To evaluate the effectiveness and tolerability of TNK in patients with ST-segment-elevation myocardial infarction in a secondary referral Malaysian hospital.

Methods

This was a single-center retrospective case series based on the medical records of patients with ST-segment-elevation myocardial infarction admitted to the cardiac care unit between January 2016 and May 2019. Data regarding the mortality status and date of death were collected from the database of the National Registration Department of Malaysia.

Results

Data for 30 patients with ST-segment-elevation myocardial infarction, who received weight-adjusted doses of TNK, were analyzed. The patients’ mean (SD) age was 62 (14) years, and 77% were men. The median time to treatment was 265 minutes (interquartile range = 228–660 minutes), and the clinical success rate of thrombolysis was 79%. The overall all-cause in-hospital mortality rate was 33%. The 1-year survival rates were higher in patients achieving a time to treatment ≤360 minutes (P = 0.03), with a trend toward greater survival in this group at 30 days. Similarly, a trend toward lower in-hospital all-cause mortality was observed in this group (21% vs 50%; P = 0.12). Only 1 patient (3%), who had a HAS-BLED score based on hypertension, abnormal liver/renal function, stroke history, bleeding history or predisposition, labile international normalized ratio, old age, drug/alcohol use of 5, developed major bleeding that required blood transfusion. No cases of ischemic stroke, nonmajor bleeding, in-hospital reinfarction, or TNK-induced allergic reaction were identified.

Conclusions

We hypothesized that the mortality-related outcomes of TNK in patients with ST-segment-elevation myocardial infarction were influenced by TTT, with TTT ≤360 minutes indicating a better prognosis than TTT >360 minutes. TNK-induced bleeding-related complications were minimal in low-risk patients. Further local studies are needed to compare TNK's profile with that of streptokinase, which is a common agent currently used in clinical practice in Malaysian public hospitals. (Curr Ther Res Clin Exp. 2021; 82:XXX–XXX)

Prehospital Evaluation, ED Management, Transfers, and Management of Inpatient STEMI

ST elevation myocardial infarction diagnoses have reduced in number over the past 10 years; however, associated morbidity and mortality remain high. Societal guidelines focus on early diagnosis and timely access to reperfusion, preferably percutaneous coronary intervention (PCI), with fibrinolytics reserved for those who cannot receive timely PCI. Proposed algorithms recommend emergency department bypass in stable patients with a clear diagnosis to reduced door-to-balloon time. Emergency providers should limit their evaluation, focusing on life-threatening comorbidities, unstable vitals, or contraindications to a catheterization laboratory. In-hospital patients prove diagnostically challenging because they may be unable to express symptoms, and reperfusion strategies can complicate other diagnoses.

Predictive model of increased mortality and bed occupancy if thrombolysis becomes the initial treatment strategy for STEMI during the SARS-CoV-2 pandemic

During the current SARS-CoV-2 pandemic the restructure of healthcare services to meet the huge increase in demand for hospital resource and capacity has led to the proposal that where necessary ST elevation myocardial infarction (STEMI) could be managed by intravenous thrombolysis in the first instance as a means of reducing the workforce requirements of a primary angioplasty service run at a heart attack centre. Our modelling, based on data from the UK, shows that contrary to reducing demand, the effect on both mortality and bed occupancy would be negative with 158 additional deaths per year for each 10% reduction in primary angioplasty and at a cost of ~8,000 additional bed days per year for the same reduction. Our analysis demonstrates that specialist services such as heart attack pathways should be protected during the COVID crisis to maximise the appropriate use of resource and prevent unnecessary mortality.

Frequency of Non-ST Segment Elevation Myocardial Infarction (NSTEMI) in Acute Coronary Syndrome With Normal Electrocardiogram (ECG): Insights From a Cardiology Hospital in Pakistan

Introduction

Patients presenting to the emergency department with a non-ST segment elevation myocardial infarction (NSTEMI) frequently have unremarkable electrocardiography (ECG) reports, alluding to the unreliable nature of ECG in diagnosing NSTEMI. This study aims to assess the burden of NSTEMI in acute coronary syndrome (ACS) with unremarkable ECG, elucidating that in patients presenting with acute retrosternal chest pain, NSTEMI should not be excluded unless cardiac enzyme levels are assessed.

Methods

All patients who fulfilled the inclusion criteria in the Department of Cardiology, Tabba Heart Institute, Karachi were included. After obtaining informed written consent, a detailed history was taken. Clinical examination was consequently performed, and an ECG, along with the cardiac enzymes implicated in ACS, such as troponin I, was evaluated. The proportion of normal ECGs in the context of an NSTEMI was duly noted.

Result

A total of 215 patients with ACS presenting within 24 hours of the onset of symptoms, on a background of unremarkable ECG reports, were included. One hundred thirty-eight (64.2%) were males and 77 (35.8%) were females, with the mean age being 54.3 + 7.6 years. A confirmed diagnosis of NSTEMI was made in 49 (22.8%) of the total cases.

Conclusion

The frequency of patients presenting with an NSTEMI within 24 hours of the onset of symptoms, and having normal ECG findings, was strikingly high in patients presenting to the Tabba Heart Institute, Karachi, Pakistan. These findings were more common in males and in older patients.

Clinical Implications of ST-Segment Non-Resolution after Thrombolysis for Myocardial Infarction

Failed reperfusion after thrombolytic therapy for acute myocardial infarction is common and signifies a poor prognosis. We investigated the clinical consequences of non-resolution of the ST segment after thrombolytic therapy for acute ST-elevation myocardial infarction, in 85 consecutive patients admitted to a coronary care unit lacking rapid access to angioplasty. Failed thrombolysis was defined as <50% ST-segment resolution 180 minutes after the start of thrombolytic treatment. Outcomes were measured in terms of in-hospital adverse events, length of hospital stay, and mortality at 6 weeks and 1 year. Thrombolysis was successful, in terms of ST-segment resolution, in 45 patients (53%). After adjustment for other factors, ST resolution was the only independent predictor of an uncomplicated recovery in hospital (odds ratio 6.8, 95% confidence interval 2.3 to 19.9; P<0.001). At 6 weeks and 1 year, overall mortality was lower in the ST resolution group, though these differences became non-significant on multivariate analysis. In patients who survived to hospital discharge, median length of stay was greater in successfully thrombolysed patients (9 days versus 8 days) despite their lower rate of complications. ST-segment resolution is a useful marker of successful thrombolysis and relates to clinical outcome. If assessed routinely it might assist, along with other clinical markers, in the identification of low-risk patients who can be discharged early.

Coronary artery disease in the military patient

Ischaemic heart disease is the most common cause of sudden death in the UK, and the most common cardiac cause of medical discharge from the Armed Forces. This paper reviews current evidence pertaining to the diagnosis and management of coronary artery disease from a military perspective, encompassing stable angina and acute coronary syndromes. Emphasis is placed on the limitations inherent in the management of acute coronary syndromes in the deployed environment. Occupational issues affecting patients with coronary artery disease are reviewed. Consideration is also given to the potential for coronary artery disease screening in the military, and the management of modifiable cardiovascular disease risk factors, to help decrease the prevalence of coronary artery disease in the military population.

Successful medical management of a left ventricular thrombus and aneurysm following failed thrombolysis in myocardial infarction

We report the case of a patient with an extensive anterior myocardial infarction complicated by left ventricular systolic dysfunction, left ventricular apical thrombus and an apical left ventricular aneurysm following failed thrombolysis. We obtained serial two-dimensional echocardiograms at short intervals in the acute phase and also during the months of recovery and follow up. The patient was successfully and exclusively medically managed.

The significance of circulating levels of both cardiac troponin I and high-sensitivity C reactive protein for the prediction of intravenous thrombolysis outcome in patients with ST-segment elevation myocardial infarction

OBJECTIVES

To evaluate, using continuous 12-lead ECG ST-segment monitoring, the role of circulating levels of both cardiac troponin I (cTnI) and high-sensitivity C reactive protein (hs-CRP), on presentation, in the prediction of intravenous thrombolysis outcome in patients with ST-segment elevation myocardial infarction (STEMI).

DESIGN AND SETTING

Prospective observational study in a tertiary referral centre.

PATIENTS

786 consecutive patients with STEMI, who received intravenous thrombolysis in the first 6 h from index pain.

MAIN OUTCOME MEASURES

The incidence of failed thrombolysis and of cardiac death by 30 days. Failed thrombolysis was defined as the absence of abrupt and sustained > or =50% ST-segment recovery in the first 90 min after the initiation of intravenous thrombolysis.

RESULTS

The incidence of failed thrombolysis and 30-day cardiac death was 57.4% and 11.8%, respectively. By multivariate logistic regression analysis according to tertiles of both cTnI (RR, 1.5; 95% CI 1.1 to 1.8, p = 0.004 for highest vs middle third; 2.2, 1.9 to 3.5, p<0.001 for highest vs lowest third; 1.5, 1.2 to 1.8, p = 0.001 for middle vs lowest third) and hs-CRP (RR, 2.0, 95% CI, 1.6 to 2.2; p<0.001 for highest vs middle third; 2.6, 2.1 to 3.5, p<0.001 for highest vs lowest third; 1.3, 1.2 to 1.7, p = 0.02 for middle vs lowest third), were independently associated with failed thrombolysis. Moreover, by multivariate Cox regression analysis according to tertiles of both cTnI (HR 1.2, 95% CI 1.1 to 1.8, p = 0.03 for highest vs middle third; 1.5, 1.2 to 2.2, p = 0.004 for highest vs lowest third; 1.1, 0.6 to 1.4, p = 0.6 for middle vs lowest third) and hs-CRP (HR1.2, 95% CI 1.1 to 1.6, p = 0.04 for highest vs middle third; 1.7, 1.3 to 2.6, p = 0.001 for highest vs lowest third; 1.1, 0.9 to 2.1, p = 0.1 for middle vs lowest third), were independently related with an increased risk of 30-day cardiac death.

CONCLUSIONS

High circulating levels of both cTnI and hs-CRP are related with an independent increased risk of intravenous thrombolysis failure and 30-day cardiac death in patients who received intravenous thrombolysis in the first 6 h of STEMI.

Long-term clinical outcomes after rescue angioplasty are not different from those of successful thrombolysis for acute myocardial infarction

AIMS

The long-term value of rescue percutaneous transluminal coronary angioplasty (PTCA) in patients with ST-segment elevation myocardial infarction who received thrombolytic therapy but failed to achieve early recanalization of the artery is still debated. This study aimed to compare long-term outcomes after successful thrombolysis vs. systematic attempted rescue PTCA.

METHODS AND RESULTS

A total of 362 consecutive patients with STEMI hospitalized within 6 h of symptom onset and treated with intravenous thrombolytic therapy were studied. Of these, 345 underwent coronary angiography within 90 min. Sixty per cent of patients achieved TIMI 3 flow and were treated medically; the in-hospital death rate in this group was 4%. Nine per cent of patients had TIMI 2 flow and 31% TIMI 0-1 flow. In this latter group, rescue PTCA was attempted in 85.8% with a hospital death rate of 5.5% (20% with failed vs. 4% with successful rescue PTCA, P=0.03). Eight year actuarial survival without recurrent myocardial infarction was no different in patients who had successful thrombolytic therapy and in patients with attempted rescue PTCA [78 and 95% CI (71-85) vs. 78 and 95% CI (68-87), respectively, hazard ratio: 0.93 (0.52-1.65), P=0.80]. Total mortality, cardiac mortality, and other composite endpoints also did not differ between groups.

CONCLUSION

Routine attempted rescue PTCA 90 min after thrombolytic therapy in patients with persistent occlusion of the infarct-related vessels achieves long-term clinical outcomes which do not differ from those obtained by successful thrombolysis.

Detecting failed thrombolysis in the accident and emergency department

The primary objective in managing a patient with ST segment elevation myocardial infarction (STEMI) is to establish reperfusion in the infarct-related artery and to maintain it. Two approaches to coronary reperfusion are used in the UK - primary angioplasty and intravenous thrombolysis. Primary angioplasty is the gold standard approach to managing STEMI, but in the UK (due to financial, resource and personnel limitations) this is not the first-line treatment. Thrombolytic therapy remains the most widely used approach and the benefits of such an approach are irrefutable; thrombolysis saves lives, reduces infarct size and limits left ventricular dysfunction. However, data from the thrombolytic trials also suggest that 30-40% of patients fail to reperfuse with standard thrombolytic therapy. Similar data demonstrates that patients who do not sustain adequate perfusion in the infarct-related artery have a poor prognosis and increased mortality rates. As long as thrombolysis remains the standard therapy for STEMI, it is important that patients in whom the treatment has been unsuccessful are swiftly recognised and appropriate interventions instituted. The criteria to assess successful reperfusion of the infarct-related artery need to be simple to apply, easy to interpret and non-invasive. This article will discuss the most useful criteria to make such a diagnosis and suggest approaches to enable recognition of 'failed thrombolysis' in the accident and emergency department. The current views on managing failed thrombolysis will conclude the article.

Failed reperfusion after thrombolytic therapy: recognition and management

BACKGROUND

Failed reperfusion after thrombolysis occurs in as many as 30% of patients with acute myocardial infarction (MI). Furthermore, some patients have incomplete tissue perfusion despite reperfusion of the infarct-related artery. Close assessment of the efficacy of thrombolytic administration in people with evolving acute MI is necessary, particularly with regard to myocardial perfusion status, because some patients may benefit from incremental pharmacologic or invasive reperfusion strategies.

PURPOSE AND METHOD

This article reviews a number of strategies to assess infarct-related artery patency and myocardial tissue perfusion. These include coronary angiography, continuous ST-segment monitoring, serial electrocardiography, obtaining serial serum biochemical markers of myocardial necrosis, monitoring for reperfusion arrhythmias, and assessment of changes in chest pain intensity.

CONCLUSION

The early detection of failed reperfusion is critical if incremental strategies to enhance myocardial salvage are to be considered. Continuous ST-segment monitoring is a relatively inexpensive, reliable, and accurate tool for assessing real-time myocardial perfusion.