Application of velocity vector imaging (VVI) in the evaluation of left ventricular myocardial contractile strain and dyssynchrony before and after stent implantation in patients with coronary heart disease.

Background: Percutaneous coronary intervention (PCI) has become increasingly mature and has gradually become the main treatment for coronary heart disease (CHD). However, evaluation of myocardial reperfusion after PCI remains a major clinical challenge. This study aimed to explore the VVI technique in evaluating the effect, prognosis, and follow-up of CHD patients after percutaneous coronary intervention. We performed a quantitative analysis of left ventricular myocardial contractile strain and dyssynchrony before and after stent implantation in patients by VVI.

Methods: Thirty-five patients diagnosed with CHD who underwent percutaneous coronary stenting (PCI) in the Department of Cardiovascular Medicine, Affiliated Hospital of Jiangnan University from March 2019 to October 2020 were selected as the case group. Continuous dynamic two-dimensional images of the patient's left ventricle were analyzed using VVI at 1 day before PCI (group A), 7 days after PCI (group B), and 30 days after PCI (group C). The patients' left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), left ventricle ejection fraction (LVEF), peak longitudinal strain, and peak radial strain of myocardial contraction were measured. The VVI images of 35 healthy subjects who underwent physical examination in the outpatient department of our hospital from March 2019 to October 2020 were selected as controls.

Results: There were no significant differences in the LVEF, LVEDD, and LVESD between the case and control groups (P>0.05). The peak systolic longitudinal and radial strain values at 1 month after treatment were higher than those before treatment. The differences among myocardial segments were statistically significant, except for the apical septum, base anterior, apical anterior, and base inferior segments (P<0.05). The peak systolic longitudinal and radial strain values at 1 week after treatment were not significantly different from those at 1 month after treatment, except for the base anterior septum, mid anterior, posterior, and inferior myocardial segments (P>0.05).

Conclusions: VVI technology can comprehensively and objectively evaluate the overall and local myocardial function of the left ventricle, thereby providing a novel method for the clinical treatment of CHD as well as the evaluation of curative effect and prognosis.