A new tonometric device for radial augmentation index and subendocardial viability ratio: potential use in health screening

The correlation between subendocardial viability ratio and the degree of coronary artery stenosis in patients with coronary heart disease and its predictive value for the incidence of short-term cardiovascular events

OBJECTIVES

This study aimed to analyze the ability of subendocardial viability ratio (SEVR) to predict the degree of coronary artery stenosis and the relationship between SEVR and the incidence of short-term cardiovascular endpoint events.

METHOD

The indexes of 243 patients with chest pain were collected.. Binary logistic regression analyses were performed using the dichotomous outcome of high and non-high SYNTAX scores. Receiver operating characteristic curves were employed to comparatively analyze the diagnostic efficiencies of the indices and models. A survival analysis combined with the Cox regression analysis was performed using the Kaplan-Meier method to understand the relationship between the SEVR and the incidence of cardiovascular events within 1 year in patients with coronary heart disease (CHD).

RESULTS

SEVR was significantly lower (P < 0.05) in the high-stenosis group than control and low-stenosis groups. The diagnostic efficacy of SEVR [area under the curve (AUC) = 0.861] was better than those of age (AUC = 0.745), ABI (AUC = 0.739), and AIx@HR75 (AUC = 0.659). The cutoff SEVR was 1.105. In patients with confirmed CHD who had been discharged from the hospital for 1 year, only SEVR affected survival outcomes (hazard ratio = 0.010; 95% confidence interval: 0.001-0.418; P = 0.016).

CONCLUSION

A significant decrease in SEVR predicted severe coronary artery stenosis, with a cutoff value of 1.105 and an accuracy of 0.861. In patients with CHD, the lower the SEVR, the higher was the rate of cardiovascular events at 1 year after hospital discharge.

Research Progress and Clinical Value of Subendocardial Viability Ratio

Cardiovascular disease remains the leading cause of morbidity and mortality worldwide, with ischemic heart disease being a major contributor, either through coronary atherosclerotic plaque-related major vascular disease or coronary microvascular dysfunction. Obstruction of coronary blood flow impairs myocardial perfusion, which may lead to acute myocardial infarction in severe cases. The subendocardial viability ratio, also known as the Buckberg index, is a valuable tool for evaluation of myocardial perfusion because it reflects the balance between myocardial oxygen supply and oxygen demand. The subendocardial viability ratio can effectively evaluate the function of the coronary microcirculation and is associated with arterial stiffness. This ratio also has potential value in predicting adverse cardiovascular events and mortality in various populations. Moreover, the subendocardial viability ratio has demonstrated clinical significance in a range of diseases, including hypertension, aortic stenosis, peripheral arterial disease, chronic kidney disease, diabetes, and rheumatoid arthritis. This review summarizes the applications of the subendocardial viability ratio, its particular progress in the relevant research, and its clinical significance in cardiovascular diseases.

Radial augmentation index may be an effective predictor of vascular calcification in patients on peritoneal dialysis

Vascular calcification (VC) is an important promoter of cardiovascular disease (CVD) in patients undergoing peritoneal dialysis (PD). Several indices can be used to evaluate VC, including the abdominal aortic calcification index (AACI) and carotid artery intima-media thickness (IMT); however, simpler and lesser expensive predictors, such as the radial augmentation index (RAI), should be investigated. A total of 101 patients undergoing PD were recruited to measure RAI, AACI, and carotid artery IMT and perform echocardiography. Fifty healthy controls (HCs) were recruited to undergo RAI measurement. RAI in patients undergoing PD was significantly higher than the RAI in HCs (86.25%±8.39% vs. 76.05%±9.81%, p < 0.05). Patients undergoing PD and who suffer with diabetic mellitus, hypertension, and CVD had more severe VC than those without the abovementioned diseases. In patients with PD, RAI was positively correlated with AACI (r = 0.671, p < 0.05) and carotid artery IMT (r = 0.596, p < 0.05). RAI was positively correlated with left ventricular end-diastolic dimensions (LVDd; r = 0.678, p < 0.05), left ventricular mass index (r = 0.595, p < 0.05), and negatively correlated with early-diastolic mitral inflow velocity/late-diastolic mitral inflow velocity (r = -0.342, p < 0.05) and left ventricular ejection fraction (r= -0.497, p < 0.05). Multiple linear regression analysis showed that RAI was associated with AACI, LVDd, age, and serum phosphate (p < 0.05). RAI might be an effective predictor of VC and cardiac structural/functional abnormalities in patients undergoing PD.

Primary study for detection of arterial blood pressure waveform components

The paper presents a technique to detect significant systolic peaks, the percussion (P) and tidal peak (T) and diastolic peak (D) from the arterial blood pressure (ABP) waveform. The technique is aimed at robust detection even in presence of significant noise. Singular Value Decomposition (SVD) based dominant period extraction of the ABP waveform followed by wavelet transform and local peak detection is applied to detect the points of interest. MIMIC-II ABP databse serves as a training dataset to select SVD and wavelet transform parameters and CSL Benchmark database is used to analyze the technique. Salient systolic peak detection for the CSL dataset was performed with positive predictive value and sensitivity figures of 98.48% and 99.24% respectively.