Related Experiment Video
Updated: May 20, 2025

In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography
Published on: February 16, 2016
In-Hospital Outcomes in Patients With Acute Myocardial Infarction and No Standard Modifiable Cardiovascular Risk
Yuxiu Yang1, Zaiqiang Liu1, Fei Gao1
1Department of Cardiology, Center for Geriatric Cardiovascular Disease, Beijing Anzhen Hospital Capital Medical University Beijing China.
Background:
Individuals who present with acute myocardial infarction in the absence of standard modifiable cardiovascular risk factors (ie, SMuRF-less) seem to have a significantly increased risk of mortality; however, it remains unclear whether the "SMuRF paradox" would be influenced by patients' baseline body mass index (BMI) status.
Methods:
Using data from the CCC-ACS (Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome) project from November 2014 to July 2019, we analyzed patients with acute myocardial infarction with and without SMuRFs and categorized their BMI as underweight (<18.5 kg/m2), normal weight (18.5-24 kg/m2), overweight (24-28 kg/m2), and obese (>28 kg/m2). The primary outcome was in-hospital all-cause mortality. Multivariable logistic regression models were used to estimate BMI-stratified associations between SMuRF-less status and outcomes.
Results:
The study included 44 538 patients with first-presentation acute myocardial infarction, of whom 4454 were SMuRF-less. The incidence of SMuRF-lessness declined from 16.2% to 6.5% as BMI increased by category, and it prevailed more frequently among women and older people regardless of their BMI status. Patients who were SMuRF-less had a significant increase in in-hospital mortality than patients with ≥1 SMuRF (adjusted odds ratio [OR], 1.750 [95% CI, 1.057-2.896], P<0.001). The highest mortality rate was observed in the group who were SMuRF-less and underweight (3.5%). Considering patients with ≥1 SMuRF and obesity as the reference group, the group who were SMuRF-less underweight exhibited the highest increase in mortality (adjusted OR, 3.854 [95% CI, 2.130-6.973], P<0.001).
Conclusions:
Among patients with first-presentation acute myocardial infarction, compared with those with ≥1 SMuRF, patients who were SMuRF-less have a significantly higher risk of in-hospital mortality, especially in those underweight, whereas in-hospital survival was the most favorable among patients with ≥1 SMuRF and obesity.
Registration:
URL: https://www.clinicaltrials.gov; Unique identifier: NCT0230661.
Related Concept Videos
Blood Studies for Cardiovascular System I: Cardiac Biomarkers
The essential diagnostic tools for detecting myocardial necrosis and monitoring individuals suspected of having acute coronary syndrome (ACS) include:
Troponins
Troponins, particularly cardiac troponins I and T, are the most precise and sensitive markers of myocardial injury. They are detectable within 4-6 hours of myocardial injury and remain...
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...

