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

Abstract

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 beat-to-beat 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 inde- pendently and significantly with descriptors of the pulsatile arterial load. The role of sex in these inter- relations needs further study.