Advances in the Research Application of Ultrasound Non-Invasive Stress-Strain Loop Technology in Cardiovascular Diseases

The ultrasound pressure-strain loop (PSL) technique is a non-invasive method of examining myocardial work, which takes into account the effect of cardiac afterload on deformation and combines the overall longitudinal strain force of the left ventricle with the changes in the left ventricular pressure, allowing earlier detection of possible subclinical cardiac damage in patients, and a more accurate and non-invasive assessment of the patient’s myocardial work performance. In this article, we will discuss the progress of PSL applications in cardiovascular diseases.

Left ventricular endocardial pacing predicts the reduction of left ventricular outflow tract pressure gradient immediately after percutaneous transseptal myocardial ablation in patients with hypertrophic obstructive cardiomyopathy refractory to medicatio

Background Hypertrophic obstructive cardiomyopathy （HOCM） carries an increased risk for sudden cardiac death. No data regarding the percutaneous transseptal myocardial ablation （PTSMA） and epicardial left ventricular pacing （LVP） were reported. Methods Seven patients with recurrent symptoms and increased resting left ventricular outflow tract pressure gradient （LVOTG） after PTSMA and another 14 patients with HOCM without history of PTSMA were studied. Both resting and dobutamine stress echocardiography, PTSMA and LVP were routinely performed. Results In patients without previous PTSMA procedure, mild reduction of resting LVOTG was detected at 5 minutes after left ventricular pacing, and this reduction became significant at 10 minutes. All patients were divided into successful and unsuccessful groups according to their response to LVP. In contrary to patients in unsuccessful group, resting and R-S2 stimuli-induced LVOTG during PTSMA procedure were decreased dramatically （（9±5） mmHg vs （58±12） mmHg, （12±2） mmHg vs （113±27） mmHg, P〈0.001）. Analysis of Logistic regression demonstrated that only LVOTG level dudng left ventdcular pacing was an independent factor predicting the reduction of LVOTG immediately after PTSMA （odds ratio （OR）, 0.59; 95% CI 2.67 to 5.82; P=0.0002）. Conclusion Left ventricular endocardial temporary pacing plays a critical role in predicting acute effect on the reduction of LVOTG immediately after PTSMA procedure.

Racial Differences in Left Ventricular Filling Pressure Following Acute Aerobic Exercise Between Chinese and Caucasians

Background Left ventricular filling pressure(LVFP)is an important early indicator of heart failure that is more prevalent in Caucasians than Chinese.Exercise-induced change in LVFP may provide more incremental information to assess dias-tolic function.But it was unknown whether there was difference in LVFP following acute exercise between Caucasians and Chinese.Purpose The purpose of this study was to investigate the change of LVFP following an acute 45-min aerobic exercise in healthy Caucasian and Chinese individuals.Methods Sixty participants(30 Caucasians and 30 Chinese,half was male,respectively)performed an acute bout of aero-bic exercise at 70%of heart rate reserve.Hemodynamics,Left ventricle(LV)morphology and function parameters were measured at baseline,then at 30-min and 60-min post-exercise.Results There was a similar LV ejection fraction,LV fraction shorten,lateral E/eʹand lateral eʹbetween Chinese and Caucasians at baseline.There was a significant race-by-time interaction in lateral E/eʹand lateral eʹbetween Chinese and Caucasians from pre-exercise to 30 min and 60 min after acute aerobic exercise.TheΔE/eʹwas significant correlated with baseline systolic blood pressure.Conclusion The change of LVFP was different between Chinese and Caucasians following acute aerobic exercise.The racial differences may be primarily caused by the changes of LV relaxation following exercise,baseline systolic blood pressure may also contribute to the differences.

Midterm outcomes of percutaneous transluminal septal myocardial ablation in patients with hypertrophic obstructive cardiomyopathy refractory to medication

Hypertrophic obstructive cardiomyopathy （HOCM） is a genetic disorder characterized by severe asymmetric hypertrophy of the interventricular septum （IVS） in the absence of any other systemic or cardiac diseases. The predominant abnormal haemodynamics are caused by increased left ventricular outflow tract pressure gradient （LVOTG） and abnormal systolic anterior motion of mitral valve.

Myocardial condition after transcoronary ablation predicts the curative effect in patients with hypertrophic obstructive cardiomyopathy

Transcoronary ablation of septal hypertrophy （TASH） has been recommended as an option forpatients with drug-refractory hypertrophic obstructive cardiomyopathy （HOCM）. However, its outcome is varied, and some factors are attributed to the diversity results.1 Up to now, there is no study on the influence of the ablated myocardium＇s condition on the outcome. We retrospectively analyzed the myocardial perfusion imaging （MPI） obtained before and early after TASH in our patients to explore the relationship between the ablated myocardium＇s condition and the clinical outcome.