Comparison of Mortality Outcomes in Acute Myocardial Infarction Patients With or Without Standard Modifiable Cardiovascular Risk Factors

Coronary Calcium Is Elevated in Patients with Myocardial Infarction without Standard Modifiable Risk Factors

Objectives: Recent reports have highlighted myocardial infarction (MI) patients without standard modifiable risk factors (SMRF), noting them to be surprisingly common and to have a substantial risk of adverse outcomes. The objective of this study was to address the challenge of identifying at-risk patients without SMRF and providing preventive therapy. Methods: Patients presenting between 2001 and 2021 to Intermountain Health catheterization laboratories with a diagnosis of MI were included if they also had a coronary artery calcium (CAC) scan by computed tomography within 2 years. SMRF were defined as a clinical diagnosis or treatment of hypertension, hyperlipidemia, diabetes, or smoking. The co-primary endpoints in SMRF-less patients were: (1) proportion of patients with an elevated (>50%ile) CAC score, and (2) an indication for statin therapy (i.e., CAC ≥ 100 AU or ≥75%ile). The 60-day and long-term major adverse cardiovascular events were determined. A comparison set included MI patients with SMRF. Results: We identified 429 MI patients with a concurrent CAC scan, of which 60 had no SMRF. SMRF status did not distinguish most risk factors or interventions. No-SMRF patients had a high CAC prevalence and percentile (82% ≥ 50%ile; median, 80%ile), and 77% met criteria for preventive therapy. As expected, patients with SMRF had high CAC scores and percentiles. Outcomes were more favorable for No-SMRF status and for lower CAC scores. Conclusions: Patients without SMRF presenting with an MI have a high prevalence and percentile of CAC. Wider application of CAC scans, including in those without SMRF, is promising as a method to identify an additional at-risk population for MI and to provide primary preventive therapy.

In-hospital and 1-year outcomes of patients without modifiable risk factors presenting with acute coronary syndrome undergoing PCI: a Sex-stratified analysis

Aim

A considerable proportion of patients admitted with acute coronary syndrome (ACS) have no standard modifiable cardiovascular risk factors (SMuRFs: hypertension, diabetes mellitus, dyslipidemia, and cigarette smoking). The outcomes of this population following percutaneous coronary intervention (PCI) are debated. Further, sex differences within this population have yet to be established.

Methods

This retrospective cohort study included 7,847 patients with ACS who underwent PCI. The study outcomes were in-hospital mortality, all-cause mortality, and major adverse cardio-cerebrovascular events (MACCE). The association between the absence of SMuRFs (SMuRF-less status) and outcomes among all the patients and each sex was assessed using logistic and Cox proportional hazard regressions.

Results

Approximately 11% of the study population had none of the SMuRFs. During 12.13 [11.99-12.36] months of follow-up, in-hospital mortality (adjusted-odds ratio (OR):1.51, 95%confidence interval (CI): 0.91-2.65, P:0.108), all-cause mortality [adjusted-hazard ratio (HR): 1.01, 95%CI: 0.88-1.46, P: 0.731], and MACCE (adjusted-HR: 0.93, 95%CI:0.81-1.12, P: 0.412) did not differ between patients with and without SMuRFs. Sex-stratified analyses recapitulated similar outcomes between SMuRF+ and SMuRF-less men. In contrast, SMuRF-less women had significantly higher in-hospital (adjusted-OR: 3.28, 95%CI: 1.92-6.21, P < 0.001) and all-cause mortality (adjusted-HR:1.41, 95%CI: 1.02-3.21, P: 0.008) than SMuRF+ women.

Conclusions

Almost one in 10 patients with ACS who underwent PCI had no SMuRFs. The absence of SMuRFs did not confer any benefit in terms of in-hospital mortality, one-year mortality, and MACCE. Even worse, SMuRF-less women paradoxically had an excessive risk of in-hospital and one-year mortality.

Influence of standard modifiable risk factors on ventricular tachycardia after myocardial infarction

Background

Inducible ventricular tachycardia (VT) at electrophysiology study (EPS) predicts sudden cardiac death because of ventricular tachyarrhythmia, the single greatest cause of death within 2 years after myocardial infarction (MI).

Objectives

We aimed to assess the association between standard modifiable risk factors (SMuRFs) and inducible VT at EPS early after MI.

Methods

Consecutive patients with left ventricle ejection fraction ≤40% on days 3-5 after ST elevation MI (STEMI) who underwent EPS were prospectively recruited. Positive EPS was defined as induced sustained monomorphic VT cycle length ≥200 ms for ≥10 s or shorter if hemodynamically compromised. The primary outcome was inducibility of VT at EPS, and the secondary outcome was all-cause mortality on follow-up.

Results

In 410 eligible patients undergoing EPS soon (median of 9 days) after STEMI, 126 had inducible VT. Ex-smokers experienced an increased risk of inducible VT [multivariable logistic regression adjusted odds ratio (OR) 2.0, p = 0.033] compared with current or never-smokers, with comparable risk. The presence of any SMuRFs apart from being a current smoker conferred an increased risk of inducible VT (adjusted OR 1.9, p = 0.043). Neither the number of SMuRFs nor the presence of any SMuRFs was associated with mortality at a median follow-up of 5.4 years.

Conclusions

In patients with recent STEMI and impaired left ventricular function, the presence of any SMuRFs, apart from being a current smoker, conferred an increased risk of inducible VT at EPS. These results highlight the need to modify SMuRFs in this high-risk subset of patients.

Impact of standard modifiable cardiovascular risk factors on 2-year all-cause mortality: Insights from an international cohort of 23,489 patients with acute coronary syndrome

BACKGROUND

Controversial findings have been reported in the literature regarding the impact of the absence of standard modifiable cardiovascular risk factors (SMuRFs) on long-term mortality risk in patients with acute coronary syndrome (ACS). While the prognostic additive value of SMuRFs has been well described, the prognostic role of prior cardiovascular disease (CVD) by sex is less well-known in patients with and without SMuRFs.

METHODS

EPICOR and EPICOR Asia are prospective, observational registries conducted between 2010 and 2014, which enrolled ACS patients in 28 countries across Europe, Latin America, and Asia. Association between SMuRFs (diabetes, dyslipidaemia, hypertension, and smoking) and 2-year postdischarge mortality was evaluated using adjusted Cox models stratified by geographical region.

RESULTS

Among 23,489 patients, the mean age was 60.9 ± 11.9 years, 24.3% were women, 4,582 (20.1%) presented without SMuRFs, and 16,055 (69.5%) without prior CVD. Patients with SMuRFs had a higher crude 2-year postdischarge mortality (HR 1.86; 95% CI, 1.56-2.22; P < .001), compared to those without SMuRFs. After adjustment for potential confounding, the association between SMuRFs and 2-year mortality risk was substantially attenuated (HR 1.17, 95% CI 0.98-1.41; P = .087), regardless of the type of ACS. The risk conferred by prior CVD was added to the underlying risk of SMuRFs to provide risk-specific phenotypes (eg, women with SMuRFs and with prior CVD were at higher risk of dying than women without SMuRFs and without CVD; HR 1.67, 95% CI 1.34-2.06).

CONCLUSIONS

In this large-scale international ACS cohort the absence of SMuRFs was not associated with a lower adjusted 2-year postdischarge mortality risk. Patients with both SMuRFs and prior CVD had a higher mortality irrespective of their sex.

Clinical characteristics, management, and 5-year survival compared between no standard modifiable risk factor (SMuRFless) and ≥ 1 SMuRF ACS cases: an analysis of 15,051 cases from Pakistan

BACKGROUND

There has been an increase in Acute Coronary Syndrome (ACS) patients without standard modifiable risk factors i.e. hypertension, diabetes, dyslipidemia, and tobacco use (SMuRFless) compared to the patients with ≥ 1 SMuRF but this has not been studied in South Asia despite them being a high-risk population. We conducted a comparative analysis of first episodes of ACS cases admitted to a tertiary cardiac center in Pakistan between SMuRFless and ≥ 1 SMuRF patients for clinical presentation, management, in-hospital, and 5-year mortality.

METHODS

We undertook a retrospective study and data of 15,051 patients admitted at Tabba Heart Institute (THI) with the first episode of ACS was extracted from Chest Pain-MI™, and the CathPCI Registry® registry affiliated with the National Cardiovascular Data Registry (NCDR®), USA. Logistic regression and Cox proportional algorithm yielded odds ratio (OR) and hazard ratios (HR) with 95% confidence interval (CI) for associated factors of in-patient and 5-year mortality.

RESULTS

There were 15% SMuRFless cases and in-hospital mortality was 4.1% in SMuRFless vs. 3.9% in the ≥ 1 SMuRF group (p-0.59), the difference remained insignificant after adjusting for age, gender, Killip class, multivessel disease, type of ACS, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) (Adjusted OR:1.1 [0.8, 1.3]. Unadjusted 5-year mortality was 40% lower in the SMuRFless group but the difference was insignificant after adjusting for age, gender, disease at presentation, its severity, and management (Adjusted HR 0.7 95% CI[0.5, 1.0]). STEMI, NSTEMI, Killip class, and multivessel disease increased the risk of overall 5-year mortality.

CONCLUSION

In-hospital and 5-year mortality was not different between the SMuRFless and ≥ 1 SMuRF group, there is a need to understand mediators of immediate and long-term mortality risk in SMuRFless patients.

Effect of obstructive sleep apnea on prognosis in patients with acute coronary syndromes with varying numbers of standard modifiable risk factors: insight from the OSA-ACS study

BACKGROUND

Standard modifiable risk factors (SMuRFs) increase the risk of cardiovascular events in patients with acute coronary syndrome (ACS) and are also strongly associated with obstructive sleep apnea (OSA) in a bidirectional relationship. However, the association of OSA with recurrent cardiovascular events in ACS patients based on the number of SMuRFs remains unclear. Hence, we aimed to elucidate the prognostic implication of OSA in ACS patients stratified by the number of SMuRFs.

METHODS

This was a post hoc analysis of the OSA-ACS study (NCT03362385), including 1927 patients admitted for ACS and undergoing portable sleep monitoring. OSA was defined as an apnea hypopnea index ≥ 15 events/h. The primary endpoint was major adverse cardiovascular and cerebrovascular event (MACCE) including cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina or heart failure, and ischemia-driven revascularization. Cox proportional hazards model and Kaplan-Meier analysis were used to investigated the relationship between OSA and subsequent cardiovascular events after patients were stratified by the number of SMuRFs.

RESULTS

Among 1927 patients enrolled, 130 (6.7%) had no SMuRF, 1264 (65.6%) exhibited 1-2 SMuRFs and 533 (27.7%) presented 3-4 SMuRFs. With the increase of the number of SMuRFs, the proportion of OSA in ACS patients tended to increase (47.7% vs. 51.5% vs. 56.6%), but there was no significant difference between them (P = 0.08). After the stratification of ACS patients via SMuRF numbers and adjustment for confounding factors, fully adjusted Cox regression indicated that OSA increased the risk of MACCE (adjusted HR, 1.65; 95%CI, 1.06-2.57; P = 0.026) and ischemia-driven revascularization (adjusted HR, 2.18; 95%CI, 1.03-4.65; P = 0.042) in ACS patients with 3-4 SMuRFs.

CONCLUSIONS

In hospitalized ACS patients, OSA is associated with an increased risk of MACCE and ischemia-driven revascularization among patients with 3-4 SMuRFs. Therefore, screening for OSA should be emphasized in ACS patients with 3-4 SMuRFs, and intervention trials should be prioritized in these high-risk patients.

Frequency and Outcomes of Patients Presenting with Non-ST Elevation Myocardial Infarction (NSTEMI) without Standard Modifiable Risk Factors: A US Healthcare Experience

Patients with ST-elevation myocardial infarction (STEMI), but without standard modifiable risk factors (SMuRF-less), are surprisingly common and appear to have a worse, or at best similar, short-term prognosis. However, relatively little attention has been paid to the prevalence and prognosis of SMuRF-less patients with non-STEMI (NSTEMI). The aim of our study was to identify the proportion and outcomes of SMuRF-less NSTEMI patients in a large US healthcare population. Patients with NSTEMI between 2001-2021 presenting to Intermountain Healthcare hospitals and catheterization laboratories were included. SMuRF-less status was defined as no clinical diagnosis of, or treatment for, hypertension, hyperlipidemia, diabetes, and smoking. Outcomes were assessed at 60 days and long-term for major adverse cardiovascular events (MACE: death, myocardial infarction, and heart failure hospitalization). Multivariable Cox proportional hazard regression was used to determine MACE hazard ratios (HR) for SMuRF-less versus patients with SMuRF. NSTEMI patients totaled 8196, of which 1458 (17.8%) were SMuRF-less. SMuRF-less patients were younger, more frequently male, had fewer comorbidities, and were slightly less likely to have revascularization. For SMuRF-less patients, 60-day MACE outcomes were lower (adj HR = 0.55, p < 0.0001), and this persisted for long-term MACE outcomes (adj HR = 0.64, p < 0.0001) and for each of its components. In this large US healthcare population, SMuRF-less NSTEMI presentation, as with STEMI presentation, was found to be common (17.8%). However, unlike STEMI reports, short- and long-term outcomes were better for SMuRF-less patients. Further studies to increase understanding of risk factors and preventive measures for NSTEMI in SMuRF-less patients are indicated.

Prediction models for major adverse cardiovascular events following ST-segment elevation myocardial infarction and subgroup-specific performance

Background

ST-segment elevation myocardial infarction (STEMI) patients are at a high residual risk of major adverse cardiovascular events (MACEs) after revascularization. Risk factors modify prognostic risk in distinct ways in different STEMI subpopulations. We developed a MACEs prediction model in patients with STEMI and examined its performance across subgroups.

Methods

Machine-learning models based on 63 clinical features were trained in patients with STEMI who underwent PCI. The best-performing model (the iPROMPT score) was further validated in an external cohort. Its predictive value and variable contribution were studied in the entire population and subgroups.

Results

Over 2.56 and 2.84 years, 5.0% and 8.33% of patients experienced MACEs in the derivation and external validation cohorts, respectively. The iPROMPT score predictors were ST-segment deviation, brain natriuretic peptide (BNP), low-density lipoprotein cholesterol (LDL-C), estimated glomerular filtration rate (eGFR), age, hemoglobin, and white blood cell (WBC) count. The iPROMPT score improved the predictive value of the existing risk score, with an increase in the area under the curve to 0.837 [95% confidence interval (CI): 0.784-0.889] in the derivation cohort and 0.730 (95% CI: 0.293-1.162) in the external validation cohort. Comparable performance was observed between subgroups. The ST-segment deviation was the most important predictor, followed by LDL-C in hypertensive patients, BNP in males, WBC count in females with diabetes mellitus, and eGFR in patients without diabetes mellitus. Hemoglobin was the top predictor in non-hypertensive patients.

Conclusion

The iPROMPT score predicts long-term MACEs following STEMI and provides insights into the pathophysiological mechanisms for subgroup differences.

Characteristics and outcomes of patients with no standard modifiable risk factors undergoing primary revascularization for acute myocardial infarction: Insights from the nationwide Japanese percutaneous coronary intervention registry

BACKGROUND

Identification of and therapeutic approaches to standard modifiable risk factors (SMuRFs), including hypertension, diabetes, dyslipidemia, and smoking, have led to improved survival of patients at risk for coronary events. However, recent studies have indicated that a significant proportion of patients with acute myocardial infarction (AMI) have no SMuRFs. We aimed to assess in-hospital outcomes and the prevalence of these patients using the Japanese nationwide percutaneous coronary intervention (J-PCI) registry.

METHODS

The J-PCI is a procedure-based registration program in Japan. A total of 115,437 PCI procedures were performed on patients with AMI between January 2019 and December 2020. The participants were divided into 2 groups: those with at least 1 SMuRF and those without any SMuRFs. The primary outcome was in-hospital mortality.

RESULTS

Of the 115,437 patients with AMI, 1,777 (1.6%) had no SMuRFs. Patients without SMuRFs were older; more likely to have left main disease; and more likely to present with heart failure, cardiogenic shock, and cardiac arrest than those with SMuRFs, resulting in higher rates of mechanical circulatory support use and impaired post-PCI coronary blood flow. In-hospital mortality was significantly higher in patients without SMuRFs than in those with SMuRFs (18.3% vs 5.3%, P < .001), irrespective of the presence or absence of ST-segment elevation.

CONCLUSIONS

In Japan, where annual health checks are mandated under universal health care coverage, the vast majority of patients with AMI undergoing PCI have SMuRFs. However, although small in number, patients without SMuRFs are more likely to present with life-threatening conditions and have worse in-hospital survival.

Association of clinical, laboratory and imaging biomarkers with the occurrence of acute myocardial infarction in patients without standard modifiable risk factors - rationale and design of the "Beyond-SMuRFs Study"

BACKGROUND

Acute myocardial infarction (AMI) remains the leading cause of mortality worldwide. The majority of patients who suffer an AMI have a history of at least one of the standard modifiable risk factors (SMuRFs): smoking, hypertension, dyslipidemia, and diabetes mellitus. However, emerging scientific evidence recognizes a clinically significant and increasing proportion of patients presenting with AMI without any SMuRF (SMuRF-less patients). To date, there are no adequate data to define specific risk factors or biomarkers associated with the development of AMIs in these patients.

METHODS

The ''Beyond-SMuRFs Study'' is a prospective, non-interventional cohort trial designed to enroll patients with AMI and no previous coronary intervention history, who undergo coronary angiography in two academic hospitals in Thessaloniki, Greece. The rationale of the study is to investigate potential relations between SMuRF-less AMIs and the clinical, laboratory and imaging profile of patients, by comparing parameters between patients with and without SMuRFs. Complete demographic and comprehensive clinical data will be recorded, Venous blood samples will be collected before coronary angiography and the following parameters will be measured: total blood count, standard biochemistry parameters, coagulation tests, hormone levels, glycosylated hemoglobin, N- terminal pro-B-type natriuretic peptide and high-sensitivity troponin T levels- as well as serum levels of novel atherosclerosis indicators and pro-inflammatory biomarkers. Furthermore, all participants will undergo a complete and comprehensive transthoracic echocardiographic assessment according to a pre-specified protocol within 24 h from admission. Among others, 2D-speckle-tracking echocardiographic analysis of cardiac chambers and non-invasive calculation of myocardial work indices for the left ventricle will be performed. Moreover, all patients will be assessed for angiographic parameters and the complexity of coronary artery disease using the SYNTAX score. Multivariable linear and logistic regression models will be used to phenotypically characterize SMuRF-less patients and investigate independent clinical, laboratory, echocardiographic and angiographic biomarkers-predictors of SMuRF-less status in AMI.The first patient was enrolled in March 2022 and completion of enrollment is expected until December 2023.

DISCUSSION

The ''Beyond-SmuRFs'' study is an ongoing prospective trial aiming to investigate potential clinical, laboratory and imaging biomarkers associated with the occurrence of AMIs in SMuRF-less patients. The configuration of these patients' profiles could lead to the development of personalized risk-stratification models predicting the occurrence of cardiovascular events in SΜuRF-less individuals.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05535582 / September 10, 2022.

Management and outcomes of patients admitted with type 2 myocardial infarction with and without standard modifiable risk factors

BACKGROUND

Whilst it is known patients without standard modifiable cardiovascular risk factors (SMuRF; hypertension, diabetes, hypercholesterolaemia, smoking) have worse outcomes in Type 1 acute myocardial infarction (AMI), the relationship between type 2 AMI (T2AMI) and outcomes in patients with and without SMuRF is unknown. This study aimed to determine the prevalence, characteristics and clinical outcomes of patients hospitalised with T2AMI based on the presence of SMuRF.

METHODS

Using the National Inpatient Sample, all hospitalizations with a primary discharge diagnosis of T2AMI were stratified according to SMuRF status (SMuRF and SMURF-less). Primary outcome was all-cause mortality while secondary outcomes were major adverse cardiovascular and cerebrovascular events (MACCE), major bleeding and ischemic stroke. Multivariable logistic regression was used to determine adjusted odds ratios (aOR) with 95% confidence intervals (95% CI).

RESULTS

Among 17,595 included hospitalizations, 1345 (7.6%) were SMuRF-less and 16,250 (92.4%) were SMuRF. On adjusted analysis, SMuRF-less patients had increased odds of all-cause mortality (aOR 2.43, 95% CI 1.83 to 3.23), MACCE (aOR 2.32, 95% CI 1.79 to 2.90) and ischaemic stroke (aOR 2.57, 95% CI 1.56 to 4.24) compared to their SMuRF counterparts. Secondary diagnoses among both cohorts were similar, with respiratory disorders most prevalent followed by cardiovascular and renal disorders.

CONCLUSIONS

T2AMI in the absence of SMuRF was associated with worse in-hospital outcomes compared to SMuRF-less patients. There was no SMuRF-based difference in the secondary diagnoses with the most common being respiratory, cardiovascular, and renal disorders. Further studies are warranted to improve overall care and outcomes of SMuRF-less patients.