Diastolic Values Research Articles

Importance of Considering Temporal Variations in Pulse Wave Velocity for Accurate Blood Pressure Prediction.

Continuous, cuffless blood pressure (BP) monitoring devices based on measuring pulse wave velocity (PWV) or pulse transit time (PTT) are emerging but are often plagued by large prediction errors. A key issue is that these techniques typically rely on a single PWV value, assuming a linear response and small arterial wall deformations. However, arterial response to BP is inherently nonlinear, with PWV varying over time [PWV(t)] by up to 50% during a cardiac cycle. This study evaluates the impact of assuming a single PWV on BP prediction accuracy. Using a Fluid-structure Interaction (FSI) testbed, we simulate the radial and common carotid arteries with the Holzapfel-Gasser-Ogden (HGO) constitutive model to capture nonlinear arterial behavior under a pulsatile physiological blood flow. Pressure data from FSI simulation are used as the ground truth, while inner area A(t) and two PWV values, at diastole and systole, serve as inputs to BP prediction models. Two models are tested: one using a single PWV value, emulating existing PWV-based BP prediction methods; another using the two PWV values to account for PWV(t). The single-PWV BP model produced prediction errors of 17.44mmHg and 6.57mmHg for the radial and carotid arteries, respectively. The model incorporating two PWV values reduced these errors by 90.6% and 96.8%, respectively. Relying on a single PWV in BP prediction models can lead to significant errors. To improve BP accuracy, future efforts should focus on incorporating PWV(t), or at least both diastolic and systolic PWV values, into these models.

Passive Aortic Counterpulsation to Reduce Pressure Pulse During Aortic Prosthesis Insertion and Reduce Endoleaks Formation: A Preliminary In Silico Investigation

Over 10% of patients undergoing aortic endograft implantation experience endoleaks within a few years. In the case of type 1a endoleaks, a crack forms between the aorta and the prosthesis collar, allowing blood to pass. This blood fills the aneurysmal sac and can lead to its rupture. None of the strategies, such as prostheses with barbs and hooks or ad hoc pharmacological therapies, can prevent the phenomenon. An alternative approach is to reduce diameter oscillations due to pulsating pressure to improve the endoprosthesis adhesion to the internal vessel walls during the initial post-implantation phases. To reach this objective, we propose to use a passive intra-aortic balloon pump (PIABP) inserted and then maintained inside the vessel immediately after the surgical procedure. We tested our hypothesis in a mechanical mock of the cardiovascular system. A silicon aorta with physiological behavior was created for this purpose. The PIABP was inflated to increasing pressures between systolic and diastolic values (120/80 mmHg). For each aorta and each condition, the variations in aortic diameter between systole and diastole, and the pressure variations, were measured. For the normal aorta, with a PIABP pressure of 110 mmHg, the variations in diameter were reduced by 38%. Assuming an endoprosthesis with a diameter of 30 mm (oversized by 5% compared to the diastolic diameter), the time the oscillations are higher than 30 mm is also reduced by 36%. The results are positive and suggest the usefulness of a biomechanical approach to the problem of type 1a endoleaks. Further in silico and clinical trials are necessary to validate the method.

The impact of preoperative four-chamber strain on failure of the maze IV procedure for atrial fibrillation: insights from conventional and speckle-tracking echocardiography

Abstract Background Prior studies have linked decreased left atrial (LA) and left ventricular (LV) function to the failure of both catheter ablation and surgery for atrial fibrillation (AF). Yet, the effects of right atrial (RA) and right ventricular (RV) function on the failure of interventional therapy remain unexplored. This study evaluates four-chamber strain parameters using conventional echocardiography and speckle-tracking analysis to evaluate the contributions of preoperative left heart and right heart function to the failure of surgery for atrial fibrillation. Methods We retrospectively analyzed 821 patients who had surgical AF ablation, using pre- and postoperative data from electronic records to assess AF recurrence and thromboembolic events. Of these, 531 had LA ablation only and 290 had bi-atrial Maze-IV procedures. Four-chamber strain was evaluated via speckle-tracking on preoperative echos with TomTec Arena, excluding low-quality images. Univariate and multivariate logistic regression analyses were conducted to assess the influence of AF duration, LV ejection fraction, age, and gender on post-PAF surgery AF recurrence, thromboembolic events with results shown as odds ratios (ORs) in the table. An OR over 1.00 indicates a higher recurrence risk per variable increment. SAS software was used for all statistical analysis. Results In our cohort with a median age of 67.4±11.0 (46.2% female), unadjusted analyses revealed that increased LA and RA volumes and decreased RV free wall strain were significantly associated with AF recurrence post-surgical ablation. Conversely, each unit decrease in LA and RA peak reservoir strain corresponded to a 6% increase in the risk of AF recurrence, indicating an inverse relationship. Adjusted analyses for LA and RA end diastolic volumes and strain values showed a similar direction of association with AF recurrence, though these were not statistically significant. Similarly, lower LA and RA peak strains and larger atrial volumes were suggestive of an increased risk for postoperative thromboembolic stroke, but did not reach statistical significance, potentially due to the low event rate (1.8% of the cohort). Conclusion Conventional echocardiography offers a practical tool for identifying patients at high risk for AF recurrence and potential thromboembolic events after AF ablation surgery. Our study confirms that reduced preoperative LA, RA and RV strain values and enlarged volumes of LA and RA are strongly associated with AF recurrence following surgical ablation. Additionally, RA strain and volume are as predictive as LA metrics, underscoring their importance in risk stratification. These echocardiographic parameters may also hold value in forecasting the likelihood of postoperative stroke.

Understanding perioperative risk determinants in carotid endarterectomy: the impact of compromised circle of Willis morphology on inter-hemispheric blood flow indices based on intraoperative internal carotid artery stump pulse pressure and backflow patterns.

Carotid artery stenosis (CAS) often requires surgical intervention through carotid endarterectomy (CEA) to prevent stroke. Accurate cerebrovascular risk assessments are crucial in CEA, as poor collateral circulation can lead to insufficient interhemispheric blood flow compensation, resulting in ischemic complications. Therefore, understanding perioperative risk determinants is vital. This study aims to determine the impact of compromised circle of Willis (CoW) morphology on inter-hemispheric blood flow, focusing on indices based on intraoperative internal carotid artery stump pulse pressure and backflow patterns. In 80 CAS patients who underwent CEA, preoperative CT angiography for CoW was conducted. Patients were categorized into five subgroups based on their CoW anatomy and three additional groups based on intraoperative internal carotid artery (ICA) stump backflow patterns evaluated by the surgeon. Continuous blood pressure signals, including systolic, diastolic, mean, and pulse pressure values, were recorded during the procedure. The relationship between CoW anatomical variants and the systolic and diastolic segments of the averaged pressure waveforms, particularly diastolic pressure decay, was analyzed. The correlation between CoW anatomy and stump backflow intensity was also examined. Significant variability in ICA stump backflow and pressure values was evident across CoW variants. Patients with compromised CoW morphology exhibited weaker backflow patterns and lower ICA stump pulse pressure values, consistent with impaired interhemispheric blood flow. Notably, ICA stump diastolic pressure decay was consistent across most CoW variant groups, indicating developed collateral circulation in cases with CoW anomalies. Thus, impaired CoW integrity is associated with compromised interhemispheric blood flow indices based on intraoperative ICA stump pulse pressure and backflow patterns during CEA. Integrating intraoperative pulse waveform analysis with preoperative CT angiography provides a more detailed assessment of cerebrovascular risk, guiding the selective use of shunts. This combined approach may improve surgical outcomes and patient safety by identifying patients at increased risk of perioperative neurological events due to CoW anomalies.

Seasonal variation in home blood pressure during pregnancy and frequency of hypertensive disorders of pregnancy: a multicenter prospective study of home blood pressure measurements in pregnant women using information technology.

This multicenter prospective study investigated seasonal variation in home blood pressure (HBP) during pregnancy and its association with the frequency of hypertensive disorders of pregnancy (HDP) and developed trimester-specific upper limits of HBP according to season. Low-risk women with singleton pregnancies were recruited at six university hospitals and three maternity clinics. HBP was measured by a sphygmomanometer twice daily and recorded online using a mobile application. HBP was evaluated according to season (winter, spring, summer, and autumn) and gestational age. Of 705 women recruited, 603 were finally included. Mean diastolic HBP values were lowest in summer and highest in winter throughout pregnancy (mean difference between summer and winter, 3.5-4.6 mmHg). Mean systolic HBP values were also lowest in summer and highest in winter except during the early period of the second trimester (mean difference between summer and the season with the highest value, 2.5-3.4 mmHg). HDP was diagnosed in 32 women (5.3%). The risk of HDP was significantly higher in women who delivered in spring and autumn but not in winter compared with summer. The rounded upper limit of HBP was 120/80 mmHg in the first trimester, 120/75 mmHg in the second trimester, and 125/80 mmHg in the third trimester for summer and 125/85 mmHg, 125/80 mmHg, and 130/85 mmHg, respectively, for other seasons. Systolic and diastolic HBP were lowest in summer throughout pregnancy. Seasonal variation should be considered when interpreting HBP and the risk of HDP during pregnancy.

Feasibility of fractal dimension analysis for left ventricular trabecular complexity using cardiac computed tomography

AimsTo evaluate the consistency between fractal dimensions (FD) derived from cardiac computed tomography (CT-FD) and cardiac magnetic resonance (MR-FD) in assessing left ventricular trabecular complexity. MethodsThis retrospective study included 170 patients who underwent CCT and CMR scans within two weeks. Five short-axis cine images were selected at end-diastole: one basal, three mid, and one apical slice. Short-axis CCT views were reconstructed and aligned with the cine images. CT-FD and MR-FD values were calculated for each slice, with mean values determined for each patient. Severe left ventricular hypertrophy (LVH) was defined as a maximum wall thickness > 15 mm in end-diastolic cine images. ResultsThe diastolic CT-FD and MR-FD values exhibited high consistency, with values of 1.253 ± 0.091 and 1.250 ± 0.102, respectively (n = 535, ICC = 0.882, 95 % CI: 0.861–0.899, P < 0.001). Similarly, the systolic CT-FD and MR-FD values demonstrated good consistency, with values of 1.268 ± 0.072 and 1.286 ± 0.093, respectively (n = 390, ICC = 0.720, 95 % CI: 0.669–0.765, P < 0.001). For subgroups of systolic NLVH and LVH, the ICCs were 0.773 (n = 305, CI: 0.723–0.814, P < 0.001) and 0.565 (n = 85, 95 % CI: 0.402–0.694, P < 0.001), respectively. The diagnostic efficacy of mean CT-FD aligned with that of mean MR-FD in distinguishing abnormal cardiac conditions from the CMR-negative group. ConclusionsCCT is a feasible method for assessing left ventricular trabecular complexity, with good agreement with CMR, except in cases of severe left ventricular hypertrophy during systole.

Assessment of Biventricular Systolic and Diastolic Function Using Conventional and Strain Echocardiography in Children with Sickle Cell Disease Surviving 1-year After Hematopoietic Stem Cell Transplant.

Hematopoietic stem cell transplant (HSCT) is a potentially curative therapy for children with sickle cell disease (SCD). The effects of HSCT on ventricular function are not well characterized in children with SCD. Echocardiograms from children with SCD who underwent HSCT between 2007 and 2017 were retrospectively analyzed before and 1-year after HSCT. Left ventricular (LV) volumes, mass, and ejection fraction were calculated by the 5/6 area*length method. LV end-diastolic and systolic dimensions, septal, and posterior wall thickness, and fractional shortening were measured by M-mode. Mitral and tricuspid inflow Dopplers (E and A waves) as well as mitral, tricuspid, and septal tissue Dopplers (E', A') were assessed. E/A, E'/A' and E/E' ratios were calculated. Biventricular strain imaging was performed using speckle-tracking echocardiography. Peak global systolic longitudinal and circumferential LV strain, and global longitudinal right ventricular strain, as well as early and late diastolic strain rate, were measured on LV apical 4-chamber, LV short-axis mid-papillary, and RV apical views, respectively. Forty-seven children (9.7 ± 5.5years, 60% male) met inclusion criteria. Pre-HSCT, subjects had mild LV dilation with normal LV systolic function by conventional measure of ejection fraction and fractional shortening. There was a significant reduction in LV volume, mass, and ejection fraction after HSCT, but measurements remained within normal range. LV longitudinal and circumferential strain were normal pre-HSCT and showed no significant change post-HSCT. RV strain decreased after HSCT, but the absolute change was small, and mean values were normal both pre- and post-HSCT. Conventional measures of diastolic function were all normal pre-HSCT. Post-HSCT there was a reduction in select parameters, but all parameters remained within normal range. Early and late diastolic strain rate parameters showed no significant change from pre- to post-HSCT. At one-year after HSCT in children with SCD conventional measures of systolic and diastolic function are within normal limits. Except for a small decrease in RV systolic strain with values remaining within normal limits, systolic strain and diastolic strain rate values did not significantly change 1-year after HSCT.

Traditional Chinese Medicine (TCM)-Inspired Fully Printed Soft Pressure Sensor Array with Self-Adaptive Pressurization for Highly Reliable Individualized Long-Term Pulse Diagnostics.

Reliable, non-invasive, continuous monitoring of pulse and blood pressure is essential for the prevention and diagnosis of cardiovascular diseases. However, the pulse wave varies drastically among individuals or even over time in the same individual, presenting significant challenges for the existing pulse sensing systems. Inspired by pulse diagnosis methods in traditional Chinese medicine (TCM), this work reports a self-adaptive pressure sensing platform (PSP) that combines the fully printed flexible pressure sensor array with an adaptive wristband-style pressure system can identify the optimal pulse signal. Besides the detected pulse rate/width/length, "Cun, Guan, Chi" position, and "floating, moderate, sinking" pulse features, the PSP combined with a machine learning-based linear regression model can also accurately predict blood pressure such as systolic, diastolic, and mean arterial pressure values. The developed diagnostic platform is demonstrated for highly reliable long-term monitoring and analysis of pulse and blood pressure across multiple human subjects over time. The design concept and proof-of-the-concept demonstrations also pave the way for the future developments of flexible sensing devices/systems for adaptive individualized monitoring in the complex practical environments for personalized medicine, along with the support for the development of digital TCM.

Assessing diastolic function using CMR as an alternative to echocardiography: age- and gender-related normal reference values.

Impaired diastolic function is associated with a variety of diseases such as myocarditis or dilated cardiomyopathy. Currently, echocardiography is the standard method for assessing diastolic function. Recently, it has been postulated that cardiovascular magnetic resonance (CMR) is an at least equivalent or superior alternative to echocardiography. To assess CMR-based age- and gender-dependent diastolic functional normal reference values, pulmonary venous and transmitral blood-flow parameters were examined in heart-healthy test persons. Flow-sensitive phase-contrast CMR imaging was performed in the right upper pulmonary vein (RUPV) and at the level of the mitral valve (MV) in 183 healthy subjects (age 10-70years; 97 women, 86 men). The data wasdistributed as evenly as possible across all groups. Strong age-dependence was observed for PV S/D; r = 0.718, p < 0.001 (Pearson product-moment correlation) and for transmitral MV E/A; ρ = -0.736, p < 0.001 (Spearman's Rho correlation). Moderate age-dependence was found for PV slope D-wave; r = 0.394, p < 0.001. Except for MV slope E-wave (male -292cm/s2 interquartile range (IQR) {-338; -243} vs. female -319 ± 82cm/s2; p = 0.047), no gender-related differences were observed. In a subgroup (N = 100), CMR data were compared with echocardiographic data. Strong correlation was found between CMR and echocardiography for PV S/D; r = 0.545, p < 0.001 and MV E/A; ρ = 0.692, p < 0.001. Diastolic functional parameters change with age, while gender-differences are small. CMR and echocardiography showed similar PV S/D and MV E/A ratios, making CMR a promising alternative for assessing diastolic function.

Comparative Analysis of The Effectiveness of Antihypertensive Therapy Including Spironolactone and Eplerenone in Patients With Essential Hypertension and Atrial Fibrillation.

To perform a comparative analysis of the efficacy of antihypertensive therapy (AHT) containing spironolactone or eplerenone in patients with essential arterial hypertension (AH) and atrial fibrillation (AF). The study included 99 male and female patients with essential AH complicated by permanent AF, who were receiving the outpatient treatment at the National Specialized Scientific and Practical Medical Center of Cardiology (Tashkent). The patients aged 61.3±9.5 years, the mean duration of AH was 12.9±8.3 years. All patients were divided into two groups: Group 1, patients who completed a 6-month combination AHT containing spironolactone (n=51); Group 2, patients who completed a 6-month combination AHT containing eplerenone (n=48). AF was diagnosed by electrocardiogram (ECG) and/or 24-hour ECG monitoring according to standard diagnostic criteria. The ECG study was performed in compliance with the American Society of Echocardiography Guidelines in M- and B-modes. The degree of structural vascular alterations was determined by the intima-media thickness of the common carotid artery by duplex scanning and microalbuminuria in morning urine. The concentrations of sex hormones were measured by the enzyme immunoassay. The serum concentrations of lipids, glucose, creatinine, and uric acid were measured by the enzymatic method. The glomerular filtration rate (GFR) was calculated with the EPI formula. Results of all studies were considered statistically significant at p&lt;0.05. The proportion of patients who achieved the target diastolic blood pressure (BP) values was significantly greater in the eplerenone-containing treatment group than in the spironolactone-containing treatment group: 87.8% vs. 67.5% (p=0.043). The proportion of patients who simultaneously achieved the target systolic and diastolic BP values was slightly greater in the eplerenone-containing treatment group than in the spironolactone-containing group (100% vs. 92.1%, p=0.060). The best cardioprotective efficacy was observed in the group of combination AHT containing eplerenone. Specifically, in Group 2, the left ventricular ejection fraction (LVEF) was significantly improved compared to Group 1: from 55.4±10.6% at baseline to 52.6±9.1% in Group 1 (p&gt;0.05) and from 54.8±8.8% at baseline to 58.2±6.4% in Group 2 (p&lt;0.02). Only in Group 2, the left atrial volume index (LAVI) was significantly decreased compared to Group 1. Thus, in Group 1, the LAVI changed from 42.2±15.1 ml/m2 at baseline to 40.4±12.2 ml/m2 (p&gt;0.05) and in Group 2, from 41.2±15.3 ml/m2 at baseline to 37.3±13.5 ml/m2 after the treatment (p&lt;0.05); the ∆% LAVI in the eplerenone group was -5.9% vs. -0.36% in the spironolactone group. In men of Group 1, estradiol significantly increased from 13.9±12.6 pmol/l at baseline to 22.7±12.4 pmol/l (p&lt;0.001). The good antihypertensive efficacy of the 6-month combination therapy containing eplerenone was significantly superior to spironolactone in achieving the target BP values. The eplerenone-containing treatment significantly improved LVEF and decreased LAVI compared to the spironolactone-containing treatment. A trend towards a beneficial effect of the AHT containing eplerenone on concentrations of sex hormones was noted in both women and men.

Abstract 50: The Comparison of Office Blood Pressure with Morning Home Blood Pressure: Self-Automated Measurement

Background: Morning hypertension is associated with poor cardiovascular outcomes. However, office blood pressure (OBP) remains a gold standard in hypertension monitoring and management. Unfortunately, the accuracy in OBP measurement is problematic. Objectives: This study aimed to determine whether routine or unattended OBP could accurately represent home blood pressure (HBP) in patients with hypertension. Methods: We conducted a single-center, cross-sectional study. Hypertensive patients aged between 18 and 80 years, capable of performing self-automated blood pressure measurement, were included in the study. Three self-automated methods of blood pressure measurement were performed: Routine OBP, unattended OBP, and HBP. All participants were instructed to rest for at least 5 minutes prior to measuring blood pressure, and HBP was recorded twice daily, in the morning and at night, for a week after the enrolled visit without antihypertensive medication adjustment. Results: Overall 190 consecutive patients were enrolled, with a mean age of 65.2 ±7.5 years old. Half of the patients had coronary artery disease or type 2 diabetes as comorbidities. Routine OBP was significantly higher than unattended OBP and HBP. Interestingly, Systolic values of unattended OBP were similar to those of morning HBP (mean difference -0.6 ±16.0 mmHg, p=0.641) with moderate correlation (r=0.516, p&lt;0.001). Although diastolic values of unattended OBP were lower than those of morning HBP (mean difference -3.3 ±9.0 mmHg, p&lt;0.001), the values were moderately correlated (r=0.581, p&lt;0.001). Bland-Alman plots between unattended OBP and morning HBP were shown in Figure 1. Both systolic and diastolic values of unattended OBP and average HBP were significantly different (mean difference -3.5 ±14.9 mmHg, p=0.002, and 1.6 ±8.6 mmHg, p=0.013, respectively). Conclusion: Unattended OBP method could effectively represent morning HBP, thus advocating to use in clinical practice.

Home Blood Pressure Monitoring dan Health Education pada Manajemen Hipertensi Kehamilan

The incidence of hypertension in pregnancy occurs in 5 – 10 out of 100 pregnant women. Home blood pressure monitoring (HBPM) is a method of screening blood pressure at home. Pregnant women with hypertension also need health education as an effort to live a healthier life. This research aims to determine the effectiveness of HBPM and Health Education in reducing blood pressure in pregnant women. Quasi-experimental research design with nonrandomized pretest-post test group design method. Sample of 30 pregnant women with hypertension. The statistical test used the Paired Samples t-Test. The research results of Home blood pressure monitoring and Health Education were significantly effective in reducing the blood pressure of pregnant women, both systolic and diastolic values ​​with a p value of 0.000 (p &lt; 0.05). Meanwhile, in the comparison group, the systolic p value was 0.000 (p&lt;0.05), the diastolic value was 0.001 (p&lt;0.05). The combination of HBPM and Health Education can help improve hypertension management and minimize complications due to recurrent hypertension in pregnant women.

Direct comparison of whole heart quantifications between different retrospective and prospective gated 4D flow CMR acquisitions.

4D flow cardiovascular magnetic resonance (CMR) is a versatile technique to non-invasively assess cardiovascular hemodynamics. With developing technology, choice in sequences and acquisition parameters is expanding and it is important to assess if data acquired with these different variants can be directly compared, especially when combining datasets within research studies. For example, sequences may allow a choice in gating techniques or be limited to one method, yet there is not a direct comparison investigating how gating selection impacts quantifications of the great vessels, semilunar and atrioventricular valves and ventricles. Thus, this study investigated if quantifications across the heart from contemporary 4D flow sequences are comparable between two commonly used 4D flow sequences reliant on different ECG gating techniques. Forty participants (33 healthy controls, seven patients with coronary artery disease and abnormal diastolic function) were prospectively recruited into a single-centre observational study to undergo a 3T-CMR exam. Two acquisitions, a k-t GRAPPA 4D flow with prospective gating (4Dprosp) and a modern compressed sensing 4D flow with retrospective gating (4Dretro), were acquired in each participant. Images were analyzed for volumes, flow rates and velocities in the vessels and four valves, and for biventricular kinetic energy and flow components. Data was compared for group differences with paired t-tests and for agreement with Bland-Altman and intraclass correlation (ICC). Measurements primarily occurring during systole of the great vessels, semilunar valves and both left and right ventricles did not differ between acquisition types (p > 0.05 from t-test) and yielded good to excellent agreement (ICC: 0.75-0.99). Similar findings were observed for the majority of parameters dependent on early diastole. However, measurements occurring in late diastole or those reliant on the entire-cardiac cycle such as flow component volumes along with diastolic kinetic energy values were not similar between 4Dprosp and 4Dretro acquisitions resulting in poor agreement (ICC < 0.50). Direct comparison of measurements between two different 4D flow acquisitions reliant on different gating methods demonstrated systolic and early diastolic markers across the heart should be compatible when comparing these two 4D flow sequences. On the other hand, late diastolic and intraventricular parameters should be compared with caution.

EFFECTS OF SHORT-TERM PRACTICE OF FAST DEEP BREATHING EXERCISE ON PARASYMPATHETIC FUNCTIONS IN TRANS-FEMORAL AND TRANS-TIBIAL-AMPUTATION PATIENTS

Background of the Study: After lower limb amputation, the functioning parasympathetic system is compromised so the regular practice of breathing techniques improves cardiorespiratory functions. To determine the effects of short-term fast-breathing exercises on parasympathetic functions in amputees. Methodology: The study was conducted at the Armed Forces Institute of Rehabilitation Medicine Rawalpindi, on 61 stable transfemoral and transtibial amputation patients within the duration of six months (January to June 2017), performed fast deep breathing exercises Parasympathetic functions were observed through different variables. Data was analyzed using IBM® SPSS® v 21. Results: Breathing exercises showed significant effects on HR with a p-value of (0.000), the Valsalva ratio had a p-value of (0.000), and oxygen saturation was improved in both control and experimental groups with p-values of (0.000) and (0.000). Valsalva’s BP systolic and diastolic p values were (0.001) (0.012), breathing exercise BP systolic and diastolic values were (0.16) and (0.000), and orthostatic testing BP systolic and diastolic p values were (0.134) and (0.389). Post Borg scale readings showed a significant decrease in exertion level Conclusion: The study concludes that short-term fast deep breathing exercise improves cardiovagal functioning.

624 A Retrospective Review of Blood Pressure Variability (BPV) and Abdominal Aortic Aneurysm (AAA)

Abstract Background Abdominal aortic aneurysms (AAA) rupture risk increases with expansion. Understanding of factors influencing AAA growth are crucial to reduce the risk of rupture. Blood pressure (BP) is considered a contributor to AAA formation, but the association with AAA growth remains unclear. Blood pressure variability (BPV) has emerged as an important cardiovascular risk factor, yet its relationship with AAA growth has not been investigated. Method A retrospective review of 90 patients participating in a multi-centre AAA growth study (NCT05376514) was conducted. Mean growth (mm/yr) was calculated from first and most recent duplex ultrasound scans. Outpatient BP readings between scans were used to calculate BPV defined as the standard deviation (SD) of systolic and diastolic values. Patients were stratified into high and low BPV groups and again into tertiles. Mann-whitney U and unpaired T-tests were used for group comparisons, Kruskall-Wallis to assess for a dose-response relationship between tertiles of BPV. Multiple regression analysis examined variable impact on growth. Results High diastolic BPV was associated with a faster growth rate (2.05 mm/yr [IQR= 1.00 – 3.00]) vs low diastolic BPV (1.44 mm/ yr ([IQR= 0.475-2.00]p=0.036) with a significant dose-response relationship between the lowest and highest BPV tertiles (p= 0.019). DBPV was a significant predictor of AAA growth in the multiple regression model for tertile classification (p=0.016). There was no association between systolic BPV and faster AAA growth rates. Conclusions There was a significant association between higher diastolic blood pressure variability and AAA growth. DBPV may be an important risk stratification tool.

Wireless Blood Pressure Monitor with Android Integration: Tracking Systolic and Diastolic Parameters

Blood pressure measurement plays a crucial role in detecting underlying diseases in the human body. It enables the identification of conditions like heart failure, kidney failure, liver damage, and stroke, underscoring the importance of regular measurements. To facilitate independent and routine blood pressure monitoring, the development of an automatic blood pressure measuring device is essential. This research aims to design and fabricate a digital sphygmomanometer that can transmit measurements to a smartphone through the Blynk application. The blood pressure measurement is conducted using the MPX5050GP pressure sensor as the pressure detector. The device is programmed using the Esp32 microcontroller and incorporates an LCD screen to display the measurement results. The study involved measuring six participants, with each individual's blood pressure recorded ten times. The obtained measurements were then compared to those of the Omron HEM-7120 digital sphygmomanometer. The results revealed a discrepancy of ±9 mmHg in systolic values and ±7 mmHg in diastolic values between the two devices. The smallest systolic error observed was 0.4%, while the largest error reached 3%. Similarly, the smallest diastolic error was 2%, with the largest error recorded at 4.8%. The measurement errors, particularly in diastolic pressure, were influenced by the participants' fatigue, as the repeated measurements on the same arm led to slight arm movements during the process. The study demonstrated the successful transmission of measurement results to a smartphone, affirming the efficacy of the Blynk application. Additionally, the MPX5050GP sensor proved effective in detecting blood pressure. These findings highlight the potential of the developed digital sphygmomanometer as a reliable tool for blood pressure monitoring, promoting self-care and early detection of health issues.

Evaluation of fetal cerebral microvascular status and its relationship with fetal growth and development using microvascular imaging technique

The study conducted retrospective analysis design, aiming to explore the use of Microvascular Imaging Technique (MVFI) to assess fetal cerebral microcirculation and analyze the relationship between Microvascular Index (MVI) and fetal growth and development. 100 pregnant women who met the criteria for fetal growth restriction (FGR) provided in the Expert Consensus on Fetal Growth Restriction (2019 Edition) and underwent routine prenatal examinations at the Obstetrics and Gynecology Department of Peking University Third Hospital from January 2021 to June 2023 were selected as the study subjects. A normal fetus with a fetal weight less than 10 % can be classified as FGR, Pregnant women with fetal umbilical artery (UA) systolic and diastolic (S/D) values ≥3 were included in the observation group, while 200 pregnant women with normal fetuses were selected as the control group during the same period. The fetuses’ change in both groups were measured using color Doppler ultrasound, including bi-parietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). The cerebral microcirculation of the fetuses in both groups was evaluated using MVFI, and the MVI values were compared. The clinical characteristics of FGR fetuses with umbilical artery S/D ratio ≥ 3 were summarized, and the correlation between fetal cerebral microvascular status and fetal growth and development was analyzed using Pearson correlation analysis. The outcomes told that the BPD, HC, AC, and FL values of the fetuses in the control group were lower the other’s value (P < 0.05), and the MVI and peak systolic velocity of the middle cerebral artery (MCA-PSV) values were also lower in the control group (P < 0.05). Pearson correlation analysis revealed a positive correlation between fetal growth and development and MVI and MCA-PSV values in FGR fetuses. In conclusion, MVFI can monitor and quantitatively analyze fetal intracranial microcirculation, visualize slow blood flow in microvascular structures, and this study provides preliminary evidence of the close relationship between fetal cerebral microcirculation and intrauterine growth and development.

Possibilities to increase reliability and accuracy of blood pressure measurement taking into account blood hydrodynamics and biomechanics of processes during compression of shoulder tissues with a pneumatic cuff

Systolic and diastolic BP values are determined guided by measurement signals (Korotkoff tones, oscillations). The source of these signals are hydrodynamic processes occurring in the artery under the influence of cuff pressure on the upper arm. The article is devoted to the study of these processes. The value of body tissues pressure on the artery walls is equal to the value of air pressure in the cuff only at the middle of the cuff and smoothly decreases to zero to its edges. Such non-uniformity of distribution of body tissues pressure on the artery walls is caused by the physical property of elasticity of their shape, which was not taken into account earlier. Therefore, the equality of the value of blood pressure on the artery walls from its inner side and the value of body tissues pressure on the artery walls from its outer side is possible only at one point. At this point, the open part of the artery passes into its constricted part, and the point itself is called the boundary of arterial constriction. The pulsations of blood pressure in the artery caused by the heart cause rhythmic movements of this boundary along the artery. Therefore, the arterial walls open up when the constriction boundary is moved in the distal direction. When the convergence boundary is moved in the proximal direction, the walls of the artery connect. During systole, when the blood pressure exceeds the air pressure in the cuff, the boundary of compression moves distally across the middle of the cuff. At the same time, a blood flow front is formed beyond the middle of the cuff, moving towards the distal edge of the cuff. When this edge is reached, the artery opens across the entire width of the cuff. In the diastole periods following systole, the blood pressure decreases. As a result, the blood pressure drops below the air pressure in the cuff, and the arterial wall at the midpoint of the cuff interconnect again. In this case, there is a re-boundary of constriction moving in the proximal direction. Thus, the hydrodynamics of blood in the artery is completely determined by the movements of the boundary of its compression. This hydrodynamics is substantiated theoretically and confirmed experimentally. It is shown that oscillations of air pressure in the cuff, Korotkoff tones and surface pulse waves are different consequences of a single biomechanical process, which allows us to consider in detail the formation of oscillations, surface pulse waves, as well as to put forward a physically justified version of the Korotkoff tones.

NIGHTTIME ARTERIAL PRESSURE PHENOTYPES AND THEIR PROGNOSTIC VALUE IN PREGNANT WOMEN AS PREDICTORS FOR FUTURE MATERNAL AND NEONATAL EVENTS

Objective: We have previously demonstrated that some ambulatory blood pressure monitoring (ABPM) values can predict maternofoetal evens in hypertensive pregnant women. The analysis of the different nighttime blood pressure (BP) phenotypes in pregnant women is still an unknown topic. Design and method: A retrospective cohort study which followed a sequential number of 274 hypertensive pregnant patients (mean age of 32 years) from 2007 to 2022, who underwent ABPM made with a Spacelabs 90207. Data was collected and analysed in SPSS Statistics through different parametric tests. Nocturnal BP phenotypes were defined for both systolic and diastolic values as: reverse dipper (RD); non-dipper (ND); dipper (DP); and extreme dipper (ED). An event was defined as the composite endpoint of multiple adverse events: preeclampsia or eclampsia, foetal or neonatal death, prematurity, low weight at birth, gestational diabetes, and maternal death. Results: A Kaplan-Meier survival curve analysis was performed between systolic DP and ND groups, with ND showing a worse survival with a long rank of 11.331 (p&lt;0.001); and for diastolic DP and ND groups, again with ND showing a worse survival with a long rank of 15.335 (p&lt;0.001). In a further systolic nocturnal phenotypes Kaplan-Meier analysis, RS (n=6) showed the worse survival, followed by ND (n=87), while DP (n=162) and ED (n=19) showed better survival, with a log rank of 8.4 (p=0.038). For the diastolic nocturnal phenotypes Kaplan-Meier analysis, ND (n=33) showed the worse survival, followed by DP (157), while ED (81) showed better survival, with a log rank of 21.3 (p&lt;0.001). Diastolic RD showed no events, likely due to the small sample size (n=3). (Fig 1) Conclusions: This study further exemplifies the importance of ABPM in the evaluation of hypertensive pregnant women, both for its major role in diagnosis as well as prognostic value. Different nocturnal phenotypes show different survival rates, and patients without systolic or diastolic dipping seem to be at a major risk.

SINGLE-PILL COMBINATION ANTIHYPERTENSIVE THERAPY IN HYPERTENSIVE, OBESE PATIENTS: A PROSPECTIVE, EPIDEMIOLOGICAL STUDY IN ROMANIA

Objective: To assess the blood pressure (BP) management in obese, hypertensive patients under treatment with single-pill combination (SPC) antihypertensive therapy. Design and method: Prospective, observational, multicenter study, involving 192 investigators (85 cardiologists and 107 general practitioners) randomly selected from Romanian healthcare system, which included 1299 obese, hypertensive patients (Body Mass Index (BMI) of 30 kg/m2 or higher); 56.22±11years; 53.89% females) (1-month recruitment). The total study duration was 5 months (May-Aug 2023), while the patient observational period was 12 weeks (including 3 visits: baseline, at one month and at three months after inclusion). At enrolment visit each patient received a SPC antihypertensive therapy as per investigator’s decision, based on his/her own best medical judgement and in line with the current practice guidelines. Demographic data, comorbidities and data regarding hypertension and evolution of BP values in relation to the antihypertensive treatments were collected. Results: The study population had the following characteristics: BMI 34.35±4.21 kg/m2; 20.94% smokers, 56.81% with CV family history, and 52.12% had comorbidities. Among the patients with comorbidities the most frequently identified were diabetes mellitus type 2 (37.37%), valvular heart disease (20.97%), angina (19.35%) and heart failure (16.24%). At study inclusion the investigators’ perception regarding the cardiovascular (CV) risk was that only 27.02% of patients are in “very high” risk category, while according to SCORE2 and SCORE2-OP the actual calculated CV “very high” risk, was identified in 68.82% of patients. The most frequent recommended double SPC at study inclusion were perindopril/indapamide (81.68%) and olmesartan/amlodipine (5%). Hypertension was treated in all patients and systolic and diastolic BP values (SBP and DBP) and heart rate (HR) decreased significantly throughout the study (p&lt;0.001) (Fig. 1). Analyzing the patients treated with different double SPC a significant decrease in BP and HR values was observed (p&lt;0.001) for the perindopril/indapamide SPC, and olmesartan/amlodipine, respectively (Fig. 2). Conclusions: This study showed that single pill antihypertensive combinations are effective in decreasing BP and HR values in hypertensive obese patients, while correct CV risk estimation by clinicians remains challenging in their daily practice, with the tendency of underestimation.