Background Left ventricular (LV) hemodynamic condition and mechanical function are major components of overall cardiac function. Traditional evaluation of hemodynamics with Doppler ultrasound is, however, angle dependent and limited in the spatial characterization of intraventricular flow pattern. With the development of contrast echo, it is visible that blood flow forms intraventricular vortex ring during early LVfilling, which has been shown to optimise the diastolic fluid dynamics and the efficiency of systolic ejection. Vortex formation time (VFT) was introduced to characterise the optimal condition of vortex ring formation. Reduced diastolic suction after acute myocardial infarction (AMI) might lead to abnormalLVvortex ring formation. Less study was done on the hemodynamic changes in AMI assessed by VFT and its correlation with future left ventricular remodelling.
Objective We sought to investigate hemodynamic changes in AMI patients undergoing primary percutaneous coronary intervention (PCI) with VFT and its correlations with myocardial function and one-year remodelling.
Methods A total of 78 consecutive first ST-elevation AMI patients and 40 normal controls (NC) were included in the study. Within 3–5 days of the onset of AMI and at one-year follow-up, two-dimensional echocardiography, mitral valve pulse wave Doppler, mitral annular tissue Doppler were performed. Left ventricular end-diastolic and end-systolic volume (LVEDV and LVESV), mitral valve early and late diastolic velocity (MVE and MVA), mitral annular systolic (S’) and diastolic velocity (E’ and A’) at six points were measured. Mean of S’ (MS’), E’ (ME’) and A’(MA’) as well as E/E’, VFTs (simple) and LVdiastolic spherity index (SI) were calculated. Contrast echocardiography was performed to determine the infart size, based on which the AMI patients were divided into small infarct size group (SG) and large infarct size group (LG). Correlations of VFTs with parameters ofLVvolume and function as well as with one-yearLVremodeling were analysed. LV remodelling was defined as a 15% increase from the baseline in LVESV.
Results LVEDV, LVESV, EF, SI, MS’, ME’, MA’, E/E’ and VFT were different among three groups. VFTs was not significantly different between NC and SG (4.35 ± 1.07 vs. 4.24 ± 0.92, P > 0.05), and was reduced in LG (3.40 ± 0.82, PP)
Conclusions As a comprihensive index, VFTs incorporates LV geometry, size and functional parameters. It may provide a promising index in the evaluation of overall cardiac function in cardiovascular disease.