Association of muscular strength with pulsatile and steady hemodynamics in patients with acute myocardial infarction.

INTRODUCTION: Grip strength and blood pressure are strongly interrelated. Blood pressure is an essential component of arterial load, which modulates cardiac output. OBJECTIVES: We aimed to asses the correlation between grip strength and both steady and pulsatile components of arterial load in patients with acute myocardial infarction. PATIENTS AND METHODS: We included 295 participants (mean age, 63 years) with acute myocardial infarction. The following data were assessed: grip strength, echocardiography, local arterial stiffness, arterial tonometry, continuous arterial pulse, and beat­to­beat wave. RESULTS: In univariable analyses, grip strength correlated with arterial stiffness (pulse wave velocity), ventricular-arterial coupling, and measures of pulsatile arterial load: aortic characteristic impedance (Zao), total arterial compliance (TAC), and central fractional arterial pulse pressure (cFPP). In a multivariable model including age, grip strength, body mass index, systolic blood pressure, sex, and descriptors of pulsatile load, the following remained associated with grip strength: Zao (R2 for the model = 0.58; P <0.001), TAC (R2 = 0.23 for the model; P <0.001), and cFPP (R2 for the model = 0.2; P <0.001). In the second model that included sex, only Zao remained associated with grip strength (R2 for the model = 0.67). Comparisons between men and women of the adjusted mean value demonstrated that Zao and cFPP were considerably higher (P <0.001 and P = 0.02, respectively) and TAC was lower in women (P <0.001). CONCLUSIONS: In a cohort of patients with acute myocardial infarction, grip strength correlated independently and significantly with descriptors of the pulsatile arterial load. The role of sex in these interrelations needs further study.

Grip strength is associated with markers of central hemodynamics.

Objectives. Reduced muscular strength (measured by grip strength) has been associated with an increased risk of cardiovascular complications. Further research is needed to identify how muscular strength is associated with various markers of cardiovascular function to provide at least some mechanistic explanation for observed interrelations. We, therefore, addressed the question of whether handgrip (HG) strength is associated with descriptors of peripheral and central hemodynamics in the population of healthy individuals. Design. Two hundred thirty-one healthy volunteers (90 men and 141 women, mean age 54 years) were studied. Patients were asked to perform the maximum handgrip trial in the standing position with the dominant arm, using hydraulic hand dynamometer. Applanation tonometry was used to execute the non-invasive assessment of the pressure waveform. Results. HG strength was associated with various markers of hemodynamics and clinical characteristics, e.g. correlated significantly and positively with BMI [body mass index, r = 0.21, p = .001], PPA [pulse pressure amplification, r = 0.43, p < .0001], Tr [time to return of pressure wave, r = 0.43, p < .0001] and significantly and negatively with AP [augmentation pressure, r = -0.45, p < .0001]. Multiple linear regression showed that sex, handgrip and mean blood pressure were independently associated with AP (R2 = 0.38), PPA (R2 = 0.21) and Tr (R2 = 0.29). Conclusions. Our study demonstrated the association between handgrip strength and central hemodynamic metrics. These interactions may add a mechanistic explanation for the role of muscle strength as a risk marker for incident cardiovascular complications.