The Relationship between Pulse Wave Velocity and Coronary Artery Stenosis and Percutaneous Coronary Intervention: a retrospective observational study

Positive association between alkaline phosphatase and arteriosclerosis: a cross-sectional study

AIMS

Serum alkaline phosphatase (ALP) is known to be associated with cardiovascular events and cerebral arteriosclerosis. However, the link between ALP and early arteriosclerosis remains unclear. This study investigated the relationship between ALP and early arteriosclerosis assessed by brachial-ankle pulse wave velocity (Ba-PWV).

METHODS

This retrospective analysis included 5011 participants who underwent health examinations, including ALP and Ba-PWV measurement, at the Second Hospital of Hebei Medical University from 2012 to 2017. Regression analysis, smoothing function analysis in the generalized additive model (GAM), threshold effect analysis, and subgroup analyses were performed.

RESULTS

Multivariate regression analysis identified a significantly positive association between serum ALP and arteriosclerosis [odds ratio (OR) = 1.008, 95% confidence interval (CI) 1.004-1.011, P  < 0.001]. Smoothing function analysis indicated a two-stage association between ALP and arteriosclerosis. Furthermore, threshold effect analysis determined an inflection point at 135 U/l, below which the relationship was linearly positive and above which the risk of arteriosclerosis did not increase prominently with increasing ALP (OR = 1.009, 95% CI: 1.005-1.013, P  < 0.001; OR = 0.976, 95% CI: 0.952-1.002, P  = 0.068). However, ALP was not associated with arteriosclerosis only in participants with diabetes (OR = 0.996, 95% CI: 0.979-1.014, P  = 0.690). A positive association between Ba-PWV and arteriosclerosis was observed for both the arteriosclerosis and nonarteriosclerosis groups ( β  = 9.10, 95% CI: 4.67-13.54, P  < 0.001; β  = 8.02, 95% CI: 5.67-10.37, P  < 0.001).

CONCLUSION

In this study, the serum ALP level was positively associated with early arteriosclerosis, with a saturation effect beyond ALP = 135 U/l. However, the positive association between ALP and arteriosclerosis was unclear in adults with diabetes.

Arterial stiffness in acute coronary syndrome as a potential triage tool: a prospective observational study

BACKGROUND

Diagnosis and percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) are time-sensitive. Triage and algorithms identify patients at high-risk. However, additional prediction tools are warranted for prioritized care based on predicted coronary pathologies and PCI complexity. Pulse-wave velocity (PWV) is a non-invasive measurement related to cardiovascular morbidity, and their exact value in ACS evaluation is unclear.

METHODS

In patients undergoing coronary angiography (CA) and - if warranted - PCI for ACS evaluation at a tertiary university hospital in Vienna, Austria, brachial-ankle (ba)PWV and carotid-femoral (cf)PWV were prospectively measured from January 2020 to January 2021.

RESULTS

PWV was measured in 58 patients (60.3% male; 65 [61-69] years). Risk prediction scores (GRACE, CRUSADE, TIMI), cardiac enzymes, and fraction of patients with a three-vessel disease were significantly higher in the pathological PWV ranges. Adjusted for age and comorbidities, baPWV independently predicted the LAD being relevantly stenotic (crude OR=1.416 [1.143-1.755], P=0.001; adjusted OR=1.340 [1.039-1.727], P=0.024; cut-off 15.5 m/s in CART-analysis), being the culprit lesion (crude OR=1.320 [1.094-1.594], P=0.004; adjusted OR=1.311 [1.037-1.657], P=0.024; cut-off 15.5 m/s), and being totally occluded (crude OR=1.422 [1.113-1.818], P=0.005; adjusted OR=1.677 [1.189-2.366], P=0.003; cut-off 19.6 m/s). Moreover, CA or PCI complexity were associated with higher PWV.

CONCLUSIONS

Pathological PWV as a surrogate for arterial stiffness, polyvascular disease and a larger atherosclerotic burden was associated with GRACE, CRUSADE, and TIMI scores, and PCI duration and complexity. BaPWV independently predicted relevant LAD pathologies, and is suggested as a potential novel triage and prioritization tool for suspected NSTE-ACS in emergency departments.

The impact of heart rate on pulse wave velocity: an in-silico evaluation

BACKGROUND

Clinical and experimental evidence regarding the influence of heart rate (HR) on arterial stiffness and its surrogate marker carotid-to-femoral pulse wave velocity (cf-PWV) is conflicting. We aimed to evaluate the effect of HR on cf-PWV measurement under controlled haemodynamic conditions and especially with respect to blood pressure (BP) that is a strong determinant of arterial stiffness.

METHOD

Fifty-nine simulated cases were created using a previously validated in-silico model. For each case, cf-PWV was measured at five HR values, 60, 70, 80, 90, 100 bpm. With increasing HR, we assessed cf-PWV under two scenarios: with BP free to vary in response to HR increase, and with aortic DBP (aoDBP) fixed to its baseline value at 60 bpm, by modifying total peripheral resistance accordingly. Further, we quantified the importance of arterial compliance (C) on cf-PWV changes caused by increasing HR.

RESULTS

When BP was left free to vary with HR, a significant HR-effect on cf-PWV (0.66 ± 0.24 m/s per 10 bpm, P < 0.001) was observed. This effect was reduced to 0.21 ± 0.14 m/s per 10 bpm (P = 0.048) when aoDBP was maintained fixed with increasing HR. The HR-effect on the BP-corrected cf-PWV was higher in the case of low C = 0.8 ± 0.3 ml/mmHg (0.26 ± 0.15 m/s per 10 bpm, P = 0.014) than the case of higher C = 1.7 ± 0.5 ml/mmHg (0.16 ± 0.07 m/s per 10 bpm, P = 0.045).

CONCLUSION

Our findings demonstrated that relatively small HR changes may only slightly affect the cf-PWV. Nevertheless, in cases wherein HR might vary at a greater extent, a more clinically significant impact on cf-PWV should be considered.

Noninvasive estimation of aortic hemodynamics and cardiac contractility using machine learning

Cardiac and aortic characteristics are crucial for cardiovascular disease detection. However, noninvasive estimation of aortic hemodynamics and cardiac contractility is still challenging. This paper investigated the potential of estimating aortic systolic pressure (aSBP), cardiac output (CO), and end-systolic elastance (Ees) from cuff-pressure and pulse wave velocity (PWV) using regression analysis. The importance of incorporating ejection fraction (EF) as additional input for estimating Ees was also assessed. The models, including Random Forest, Support Vector Regressor, Ridge, Gradient Boosting, were trained/validated using synthetic data (n = 4,018) from an in-silico model. When cuff-pressure and PWV were used as inputs, the normalized-RMSEs/correlations for aSBP, CO, and Ees (best-performing models) were 3.36 ± 0.74%/0.99, 7.60 ± 0.68%/0.96, and 16.96 ± 0.64%/0.37, respectively. Using EF as additional input for estimating Ees significantly improved the predictions (7.00 ± 0.78%/0.92). Results showed that the use of noninvasive pressure measurements allows estimating aSBP and CO with acceptable accuracy. In contrast, Ees cannot be predicted from pressure signals alone. Addition of the EF information greatly improves the estimated Ees. Accuracy of the model-derived aSBP compared to in-vivo aSBP (n = 783) was very satisfactory (5.26 ± 2.30%/0.97). Future in-vivo evaluation of CO and Ees estimations remains to be conducted. This novel methodology has potential to improve the noninvasive monitoring of aortic hemodynamics and cardiac contractility.

Noninvasive Cardiac Output and Central Systolic Pressure From Cuff-Pressure and Pulse Wave Velocity

GOAL

We introduce a novel approach to estimate cardiac output (CO) and central systolic blood pressure (cSBP) from noninvasive measurements of peripheral cuff-pressure and carotid-to-femoral pulse wave velocity (cf-PWV).

METHODS

The adjustment of a previously validated one-dimensional arterial tree model is achieved via an optimization process. In the optimization loop, compliance and resistance of the generic arterial tree model as well as aortic flow are adjusted so that simulated brachial systolic and diastolic pressures and cf-PWV converge towards the measured brachial systolic and diastolic pressures and cf-PWV. The process is repeated until full convergence in terms of both brachial pressures and cf-PWV is reached. To assess the accuracy of the proposed framework, we implemented the algorithm on in vivo anonymized data from 20 subjects and compared the method-derived estimates of CO and cSBP to patient-specific measurements obtained with Mobil-O-Graph apparatus (central pressure) and two-dimensional transthoracic echocardiography (aortic blood flow).

RESULTS

Both CO and cSBP estimates were found to be in good agreement with the reference values achieving an RMSE of 0.36 L/min and 2.46 mmHg, respectively. Low biases were reported, namely -0.04 ± 0.36 L/min for CO predictions and -0.27 ± 2.51 mmHg for cSBP predictions.

SIGNIFICANCE

Our one-dimensional model can be successfully "tuned" to partially patient-specific standards by using noninvasive, easily obtained peripheral measurement data. The in vivo evaluation demonstrated that this method can potentially be used to obtain central aortic hemodynamic parameters in a noninvasive and accurate way.

Association of renal systolic time intervals with brachial-ankle pulse wave velocity

Aims: The renal systolic time intervals (STIs), including renal pre-ejection period (PEP), renal ejection time (ET), and renal PEP/renal ET measured by renal Doppler ultrasound, were associated with poor cardiac function and adverse cardiac outcomes. However, the relationship between renal hemodynamic parameters and arterial stiffness in terms of brachial-ankle pulse wave velocity (baPWV) has never been evaluated. The aim of this study was to assess the relationship between renal STIs and baPWV. Methods: This cross-sectional study enrolled 230 patients. The renal hemodynamics was measured from Doppler ultrasonography and baPWV was measured from ABI-form device by an oscillometric method. Results: Patients with baPWV ≧ 1672 cm/s had a higher value of renal resistive index (RI) and lower values of renal PEP and renal PEP/ET (all P< 0.001). In univariable analysis, baPWV was significantly associated with renal RI, renal PEP, and renal PEP/renal ET (all P< 0.001). In multivariable analysis, renal PEP (unstandardized coefficient β = -3.185; 95% confidence interval = -5.169 to -1.201; P = 0.002) and renal PEP/renal ET (unstandardized coefficient β = -5.605; 95% CI = -10.217 to -0.992; P = 0.018), but not renal RI, were still the independent determinants of baPWV. Conclusion: Our results found that renal PEP and renal PEP/renal ET were independently associated with baPWV. Hence, renal STIs measured from renal echo may have a significant correlation with arterial stiffness.