Thirty-day outcomes and predictors of mortality following acute myocardial infarction in northern Tanzania: A prospective observational cohort study

Characteristics and outcomes of patients with symptomatic chronic myocardial injury in a Tanzanian emergency department: A prospective observational study

BACKGROUND

Chronic myocardial injury is a condition defined by stably elevated cardiac biomarkers without acute myocardial ischemia. Although studies from high-income countries have reported that chronic myocardial injury predicts adverse prognosis, there are no published data about the condition in sub-Saharan Africa.

METHODS

Between November 2020 and January 2023, adult patients with chest pain or shortness of breath were recruited from an emergency department in Moshi, Tanzania. Medical history and point-of-care troponin T (cTnT) assays were obtained from participants; those whose initial and three-hour repeat cTnT values were abnormally elevated but within 11% of each other were defined as having chronic myocardial injury. Mortality was assessed thirty days following enrollment.

RESULTS

Of 568 enrolled participants, 81 (14.3%) had chronic myocardial injury, 73 (12.9%) had acute myocardial injury, and 412 (72.5%) had undetectable cTnT values. Of participants with chronic myocardial injury, the mean (± sd) age was 61.5 (± 17.2) years, and the most common comorbidities were CKD (n = 65, 80%) and hypertension (n = 60, 74%). After adjusting for CKD, thirty-day mortality rates (38% vs. 36%, aOR 1.03, 95% CI: 0.52-2.03, p = 0.931) were similar between participants with chronic myocardial injury and those with acute myocardial injury, but significantly greater (38% vs. 13.6%, aOR 3.63, 95% CI: 1.98-6.65, p<0.001) among participants with chronic myocardial injury than those with undetectable cTnT values.

CONCLUSION

In Tanzania, chronic myocardial injury is a poor prognostic indicator associated with high risk of short-term mortality. Clinicians practicing in this region should triage patients with stably elevated cTn levels in light of their increased risk.

Provider attitudes towards quality improvement for myocardial infarction care in northern Tanzania

INTRODUCTION

Myocardial Infarction (MI) is a leading cause of death worldwide. In high income countries, quality improvement strategies have played an important role in increasing uptake of evidence-based MI care and improving MI outcomes. The incidence of MI in sub-Saharan Africa is rising, but uptake of evidence-based care in northern Tanzania is low. There are currently no published quality improvement interventions from the region. The objective of this study was to determine provider attitudes towards a planned quality improvement intervention for MI care in northern Tanzania.

METHODS

This study was conducted at a zonal referral hospital in northern Tanzania. A 41-question survey, informed by the Theoretical Framework for Acceptability, was developed by an interdisciplinary team from Tanzania and the United States. The survey, which explored provider attitudes towards MI care improvement, was administered to key provider stakeholders (physicians, nurses, and hospital administrators) using convenience sampling.

RESULTS

A total of 140 providers were enrolled, including 82 (58.6%) nurses, 56 (40.0%) physicians, and 2 (1.4%) hospital administrators. Most participants worked in the Emergency Department or inpatient medical ward. Providers were interested in participating in a quality improvement project to improve MI care at their facility, with 139 (99.3%) strongly agreeing or agreeing with this statement. All participants agreed or strongly agreed that improvements were needed to MI care pathways at their facility. Though their facility has an MI care protocol, only 88 (62.9%) providers were aware of it. When asked which intervention would be the single-most effective strategy to improve MI care, the two most common responses were provider training (n = 66, 47.1%) and patient education (n = 41, 29.3%).

CONCLUSION

Providers in northern Tanzania reported strongly positive attitudes towards quality improvement interventions for MI care. Locally-tailored interventions to improve MI should include provider training and patient education strategies.

Evaluating the performance of the HEART score in a Tanzanian emergency department

OBJECTIVE

The HEART score successfully risk stratifies emergency department (ED) patients with chest pain in high-income settings. However, this tool has not been validated in low-income countries.

METHODS

This is a secondary analysis of a prospective observational study that was conducted in a Tanzanian ED from January 2019 through January 2023. Adult patients with chest pain were consecutively enrolled, and their presenting symptoms and medical history were recorded. Electrocardiograms and point-of-care troponin assays were obtained for all participants. Thirty-day follow-up was conducted, assessing for major adverse cardiac events (MACEs), defined as death, myocardial infarction, or coronary revascularization (coronary artery bypass grafting or percutaneous coronary intervention). HEART scores were calculated for all participants. Likelihood ratios, sensitivity, specificity, and negative predictive values (NPVs) were calculated for each HEART cutoff score to predict 30-day MACEs, and area under the curve (AUC) was calculated from the receiver operating characteristic curve.

RESULTS

Of 927 participants with chest pain, the median (IQR) age was 61 (45.5-74.0) years. Of participants, 216 (23.3%) patients experienced 30-day MACEs, including 163 (17.6%) who died, 48 (5.2%) with myocardial infarction, and 23 (2.5%) with coronary revascularization. The positive likelihood ratio for each cutoff score ranged from 1.023 (95% CI 1.004-1.042; cutoff ≥ 1) to 3.556 (95% CI 1.929-6.555; cutoff ≥ 7). The recommended cutoff of ≥4 to identify patients at high risk of MACEs yielded a sensitivity of 59.4%, specificity of 52.8%, and NPV of 74.7%. The AUC was 0.61.

CONCLUSIONS

Among patients with chest pain in a Tanzanian ED, the HEART score did not perform as well as in high-income settings. Locally validated risk stratification tools are needed for ED patients with chest pain in low-income countries.

Improving acute myocardial infarction care in northern Tanzania: barrier identification and implementation strategy mapping

BACKGROUND

Evidence-based care for acute myocardial infarction (AMI) reduces morbidity and mortality. Prior studies in Tanzania identified substantial gaps in the uptake of evidence-based AMI care. Implementation science has been used to improve uptake of evidence-based AMI care in high-income settings, but interventions to improve quality of AMI care have not been studied in sub-Saharan Africa.

METHODS

Purposive sampling was used to recruit participants from key stakeholder groups (patients, providers, and healthcare administrators) in northern Tanzania. Semi-structured in-depth interviews were conducted using a guide informed by the Consolidated Framework for Implementation Research (CFIR). Interview transcripts were coded to identify barriers to AMI care, using the 39 CFIR constructs. Barriers relevant to emergency department (ED) AMI care were retained, and the Expert Recommendations for Implementing Change (ERIC) tool was used to match barriers with Level 1 recommendations for targeted implementation strategies.

RESULTS

Thirty key stakeholders, including 10 patients, 10 providers, and 10 healthcare administrators were enrolled. Thematic analysis identified 11 barriers to ED-based AMI care: complexity of AMI care, cost of high-quality AMI care, local hospital culture, insufficient diagnostic and therapeutic resources, inadequate provider training, limited patient knowledge of AMI, need for formal implementation leaders, need for dedicated champions, failure to provide high-quality care, poor provider-patient communication, and inefficient ED systems. Seven of these barriers had 5 strong ERIC recommendations: access new funding, identify and prepare champions, conduct educational meetings, develop educational materials, and distribute educational materials.

CONCLUSIONS

Multiple barriers across several domains limit the uptake of evidence-based AMI care in northern Tanzania. The CFIR-ERIC mapping approach identified several targeted implementation strategies for addressing these barriers. A multi-component intervention is planned to improve uptake of evidence-based AMI care in Tanzania.

Adapting an Intervention to Improve Acute Myocardial Infarction Care in Tanzania: Co-Design of the MIMIC Intervention

Background

Uptake of evidence-based care for acute myocardial infarction (AMI) is suboptimal in Tanzania, but there are currently no published interventions to improve AMI care in sub-Saharan Africa.

Objectives

Co-design a quality improvement intervention for AMI care tailored to local contextual factors.

Methods

An interdisciplinary design team consisting of 20 physicians, nurses, implementation scientists, and administrators met from June 2022 through August 2023. Half of the design team consisted of representatives from the target audience, emergency department physicians and nurses at a referral hospital in northern Tanzania. The design team reviewed multiple published quality improvement interventions focusing on ED-based AMI care. After selecting a multicomponent intervention to improve AMI care in Brazil (BRIDGE-ACS), the design team used the ADAPT-ITT framework to adapt the intervention to the local context.

Findings

The design team audited current AMI care processes at the study hospital and reviewed qualitative data regarding barriers to care. Multiple adaptations were made to the original BRIDGE-ACS intervention to suit the local context, including re-designing the physician reminder system and adding patient educational materials. Additional feedback was sought from topical experts, including patients with AMI. Draft intervention materials were iteratively refined in response to feedback from experts and the design team. The finalized intervention, Multicomponent Intervention to Improve Myocardial Infarction Care in Tanzania (MIMIC), consisted of five core components: physician reminders, pocket cards, champions, provider training, and patient education.

Conclusion

MIMIC is the first locally tailored intervention to improve AMI care in sub-Saharan Africa. Future studies will evaluate implementation outcomes and efficacy.

One-Year Outcomes and Factors Associated With Mortality Following Acute Myocardial Infarction in Northern Tanzania

BACKGROUND

Little is known about long-term outcomes and uptake of secondary preventative therapies following acute myocardial infarction (AMI) in sub-Saharan Africa.

METHODS

Consecutive patients presenting with AMI (as defined by the Fourth Universal Definition of AMI Criteria) to a northern Tanzanian referral hospital were enrolled in this prospective observational study. Follow-up surveys assessing mortality, medication use, and rehospitalization were administered at 3, 6, 9, and 12 months following initial presentation, by telephone or in person. Multivariate logistic regression was performed to identify baseline clinical and sociodemographic factors associated with one-year mortality.

RESULTS

Of 152 enrolled patients with AMI, 5 were lost to one-year follow-up (96.7% retention rate). Mortality rates were 34.9% (53 of 152 participants) during the initial hospitalization, 48.7% (73 of 150 patients) at 3 months, 52.7% (78 of 148 patients) at 6 months, 55.4% (82 of 148 patients) at 9 months, and 59.9% (88 of 147 patients) at one year. Of 59 patients surviving to one-year follow-up, 43 (72.9%) reported persistent anginal symptoms, 5 (8.5%) were taking an antiplatelet, 8 (13.6%) were taking an antihypertensive, 30 (50.8%) had been rehospitalized, and 7 (11.9%) had ever undergone cardiac catheterization. On multivariate analysis, one-year mortality was associated with lack of secondary education (odds ratio, 0.26 [95% CI, 0.11-0.58]; P=0.001), lower body mass index (odds ratio, 0.90 [95% CI, 0.82-0.98]; P=0.015), and higher initial troponin (odds ratio, 1.30 [95% CI, 1.05-1.80]; P=0.052).

CONCLUSIONS

In northern Tanzania, AMI is associated with high all-cause one-year mortality and use of evidence-based secondary preventative therapies among AMI survivors is low. Interventions are needed to improve AMI care and outcomes.