People with strong legs are less likely to develop heart failure after a heart attack, according to results given today at Heart Failure 2023, a scientific meeting of the European Society of Cardiology (ESC).
Myocardial infarction is the most common cause of heart failure, with heart failure occurring in 6-9% of heart attack patients.3,4 Previous research has shown that having strong quadriceps lowers the chance of death in persons with coronary artery disease.
The idea that leg strength is linked to a decreased risk of heart failure after an acute myocardial infarction was investigated in this research. The research included 932 individuals with acute myocardial infarction who were hospitalized from 2007 to 2020 but who did not have heart failure at the time of admission or have problems related to heart failure while they were in the hospital. The median participant age was 66 years, and 753 (81%) of the participants were male.
As a gauge of leg strength, the maximum quadriceps strength was tested. Patients tightened their quadriceps muscles as much as they could for five seconds while sitting on a chair. The highest reading in kg was captured using a portable dynamometer fastened to the ankle.
The measurements were taken on both legs, and the researchers averaged the results. In order to represent strength as a percentage of body weight, quadriceps strength in kg was divided by body weight in kg and multiplied by 100. Depending on whether their result was higher or lower than the median for their sex, patients were categorized as having “high” or “low” strength.
The median percentage of body weight for women was 33%, whereas the median percentage of body weight for males was 52%. There were 481 patients with strong quadriceps strength and 451 with poor quadriceps strength. 67 individuals (7.2%), or 4.5 years of follow-up on average, had heart failure. In individuals with strong quadriceps strength and poor quadriceps strength, the incidence of heart failure was 10.2 per 1,000 person-years and 22.9 per 1,000 person-years, respectively.
The relationship between quadriceps strength (low vs. high) and the chance of getting heart failure was examined by the researchers. Age, sex, body mass index, previous myocardial infarction or angina pectoris, diabetes, atrial fibrillation, chronic obstructive pulmonary disease, peripheral arterial disease, kidney function, and prior myocardial infarction or angina pectoris were all taken into account in the analysis. High quadriceps strength was linked to a 41% decreased risk of having heart failure compared to poor quadriceps strength (hazard ratio [HR]: 0.59; 95% confidence interval).
The researchers also looked at the relationship between the continuous variable of quadriceps strength and the likelihood of getting heart failure. Each 5% increase in quadriceps strength was linked to an 11% reduction in the risk of heart failure (HR 0.89; 95% CI 0.81-0.98; p=0.014).
“Quadriceps strength is easy and simple to measure accurately in clinical practice,” said Mr. Kensuke Ueno, a physical therapist at the Kitasato University Graduate School of Medical Sciences in Sagamihara, Japan and the study's lead author. According to our research, those who are more likely to get heart failure after a myocardial infarction might be identified and given more stringent monitoring. The results need to be confirmed in more research, but they do support the idea that patients who have had a heart attack should be advised to engage in quadriceps strength training to avoid heart failure.