Changes In Diastolic Pressure Research Articles

Effects of Adrenaline Containing Local Anesthesia on Blood Pressure and Blood Glucose Levels Undergoing Tooth Extractions – A Comparative Study

Exodontia, the most common dental procedure for damaged or decayed teeth, often utilizes local anesthesia with vasoconstrictors like adrenaline. Although effective, adrenaline can impact blood glucose levels and hemodynamic parameters, particularly in hypertensive and diabetic patients. Objectives: To compare changes in blood pressure and blood glucose levels among healthy, hypertensive and diabetic patients undergoing tooth extraction with adrenaline-containing local anesthesia. Methods: A total of 177 participants were split equally into three groups: healthy, hypertensive and diabetic. Prior to and twenty minutes’ post-injection, blood pressure, and blood glucose levels were measured while a local anesthetic containing 2% lignocaine HCL with 1: 100,000 adrenaline was administered. Sample paired t test and one-way ANOVA were employed in the analysis. Results: Among hypertensive patients, random blood glucose significantly decreased post-procedure (p=0.001), while systolic blood pressure significantly increased (p<0.001) and diastolic blood pressure significantly decreased (p=0.021). Diabetic patients showed a non-significant decrease in glucose levels (p=0.209) but a significant increase in both systolic (p<0.001) and diastolic blood pressure (p=0.002). Healthy patients experienced a significant increase in systolic blood pressure (p=0.015) but no significant changes in glucose levels (p=0.873) or diastolic pressure (p=0.301). Conclusions: Adrenaline in local anesthesia significantly increases systolic blood pressure in all patient groups, with pronounced effects in hypertensive and diabetic patients. Changes in blood glucose were significant only in hypertensive patients, while changes in diabetic patients were non-significant. These findings highlight the need for careful monitoring and personalized management strategies in dental procedures to minimize potential adverse effects and ensure patient safety.

#730 Dialysis-induced changes in systolic, diastolic, and pulse pressure in maintenance hemodialysis patients

Abstract Background and Aims Hemodialysis (HD) therapy has a strong impact on cardiovascular function in both the short and long term. In the short term, the dialysis-induced changes in blood volume directly affect the arterial blood pressure (BP), frequently leading to intradialytic hypotension or hypertension, both associated with adverse outcomes. The aim of this study was to investigate the dialysis-induced changes in systolic (SBP), diastolic (DBP), and pulse pressure (PP) in maintenance HD patients and to assess their relationship with pre-HD BP. Methods 197 maintenance HD patients were studied during the middle dialysis session of the week. The mean pre-dialysis fluid overload was 2.0 ± 1.6 L (calculated as the difference between the pre-dialysis body weight and the target weight). All HD sessions lasted approximately 4 h and were performed using mainly low-flux dialyzers. SBP and DBP were measured pre-HD and post-HD using a sphygmomanometer. PP was calculated as SBP minus DBP. The patients were divided into two groups: A) patients with an intradialytic decline in SBP (∆SBP <0), and B) patients with an increase or no change in SBP during HD (∆SBP ≥0). Paired data were compared using the Student's t-test. Correlations between variables were assessed using Spearman's rho (ρ). Results During HD, SBP decreased in 120 (61%) patients (in 20 cases by more than 30 mmHg), remained unchanged in 11 (6%) patients, and increased in 66 (33%) patients (in 13 cases by more than 20 mmHg). DBP decreased in 94 (48%) patients, remained unchanged in 46 (23%) patients, and increased in 57 (29%) patients. In 76 (39%) patients both SBP and DBP decreased, whereas in 33 (17%) patients both SBP and DBP increased. In group A (n = 120), SBP, DBP, and PP decreased by 21 ± 16 mmHg (P < 0.001), 8 ± 11 mmHg (P < 0.001), and 13 ± 14 mm Hg (P < 0.001), respectively. In group B (n = 77), SBP, DBP, and PP increased by 12 ± 10 mmHg (P < 0.001), 4 ± 11 mmHg (P < 0.001), and 8 ± 13 mmHg (P < 0.001), respectively. Pre-HD SBP was 144 ± 23 mmHg in group A and 128 ± 25 mmHg in group B (P < 0.001). Pre-HD DBP was 80 ± 15 mmHg in group A and 68 ± 11 mmHg in group B (P < 0.001). In all patients combined, ∆SBP was similarly correlated with pre-HD SBP and pre-HD DBP (ρ = −0.42 in both cases, P < 0.001), whereas ∆DBP was more strongly correlated with pre-HD DBP (ρ = −0.52, P < 0.001) than with pre-HD SBP (ρ = −0.22, P < 0.01). ∆SBP was correlated with ∆DBP (ρ = 0.55, P < 0.001) and highly correlated with ∆PP (ρ = 0.78, P < 0.001). According to linear regression, SBP tended to increase during HD in patients with pre-HD SBP <118 mmHg (Fig. 1A), whereas DBP tended to increase in patients with pre-HD DBP <68 mmHg (Fig. 1B). Conclusions Patients with dialysis-induced decline in SBP (group A) had a significantly higher pre-HD BP (both SBP and DBP) compared with patients with an increasing or stable SBP (group B). This suggests that a high decline in SBP during HD appears to be more likely in patients with elevated pre-HD BP and that HD appears to have a pressure-normalizing effect in such patients. Similarly, a dialysis-induced increase in SBP or DBP appears to be more likely in patients with low values of pre-HD SBP or DBP, respectively.

Blood pressure response to extended-release naltrexone in heroin and prescription opioid users and its implications for cardiovascular morbidity

Background Consuming opioid agonists is a risk factor for cardiovascular disease particularly in intravenous heroin users. The monthly injectable extended-release opioid antagonist, naltrexone (XR-NTX) is an effective treatment for opioid use disorder. The impact of opioid receptor blockade through XR-NTX on blood pressure, a critical risk factor for cardiovascular morbidity, has not yet been characterized. Methods The study evaluated the change in blood pressure during XR-NTX treatment among 14 patients who predominately used intravenous heroin and 24 patients who used prescription oral opioids, all with opioid use disorder. Blood pressure was measured in each patient immediately before the first XR-NTX injection and ∼two weeks after the first injection. The change in diastolic and systolic pressure was compared between the heroin users and the prescription opioids users using analysis of variance. Results XR-NTX treatment was associated with significant decreases in diastolic blood pressure in the heroin group, but not in the prescription opioids group. Systolic blood pressure values in the heroin users showed a decline at trend level only. Conclusions Further research is warranted to replicate our findings and to determine whether XR-NTX effect is relatively specific to blood pressure or generalizes to other components of metabolic syndrome. Distinguishing between heroin and prescription opioid users could shed light on the unique clinical and pharmacological profiles of opioid drugs, particularly regarding their cardiovascular safety. This information can be useful in developing personalized therapeutic strategies based on the route of opioid administration.

Intra- and interday reliability of sympathetic transduction to blood pressure in young, healthy adults.

Microneurographic recordings of muscle sympathetic nerve activity (MSNA) and the succeeding changes in beat-to-beat blood pressure (i.e., sympathetic transduction) provide important insights into the neural control of the circulation in humans. Despite its widespread use, the reliability of this technique remains unknown. Herein, we assessed the intra- and interday test-retest reliability of signal-averaging sympathetic transduction to blood pressure. Data were analyzed from 15 (9 M/6 F) young, healthy participants who completed two baseline recordings of fibular nerve MSNA separated by 60 min (intraday). The interday reliability was obtained in a subset of participants (n = 13, 9 M/4 F) who completed a follow-up MSNA study. Signal-averaging sympathetic transduction was quantified as peak change in diastolic (DBP) and mean arterial pressure (MAP) following a burst of MSNA. Analyses were also computed considering different MSNA burst sizes (quartiles of normalized MSNA) and burst patterns (singlets, couplets, triplets, and quadruplets+), as well as nonburst responses. Intraclass-correlation coefficients (ICCs) were used as the main reliability measure. Peak changes in MAP [intraday: ICC = 0.76 (0.30-0.92), P = 0.006; interday: ICC = 0.91 (0.63-0.97), P < 0.001] demonstrated very good to excellent reliability. Sympathetic transduction of MSNA burst size displayed moderate to very good reliability, though the reliability of MSNA burst pattern was poor to very good. Nonburst responses revealed poor intraday [ICC = 0.37 (-1.05 to 0.80), P = 0.21], but very good interday [ICC = 0.76 (0.18-0.93), P = 0.01] reliability. Intraday reliability measures were consistently lower than interday reliability. Similar results were obtained using DBP. Collectively, these findings provide evidence that the burst-triggering signal-averaging technique is a reliable measure of sympathetic transduction to blood pressure in young, healthy adults.NEW & NOTEWORTHY We found that signal-averaging sympathetic transduction to blood pressure displayed very good to excellent intra- and interday test-retest reliability in healthy, young adults. Reliability analyses according to muscle sympathetic burst size, burst pattern, and nonburst response were less consistent. Results were similar when using diastolic or mean arterial pressure in the transduction calculation. These findings suggest that the signal-averaging technique can be used with confidence to investigate sympathetic transduction to blood pressure in humans across time.

Respuesta hemodinámica a dosis subanestésicas de ketamina en dolor posoperatorio: revisión sistemática

Introduction: Low-dose ketamine infusions have shown analgesic effectiveness for the management of postoperative pain. The impact of low-dose ketamine infusions on cardiovascular response is dose-dependent and requires a better knowledge about its effects on this population.&#x0D; Objective: To conduct a systematic review to describe changes in systolic, diastolic and mean arterial pressure, and heart rate 24, 48 and 72 hours after surgery.&#x0D; Methods: Randomized, controlled trials were reviewed in the Cochrane Library, PubMed, EMBASE, SciELO, Lilacs and grey literature on low-dose ketamine infusions for the study variables. The quality of the studies was assessed using the Cochrane’s risk of bias tool.&#x0D; Results: Six randomized, controlled trials with 641 patients were included. Low-quality evidence was found suggestive of a lack of certainty of any significant differences in the systolic blood pressure variables at 24 hours (mean standard deviation -1.00, 95 % CI: -7.27 to 5.27). A statistically significant higher mean heart rate at 24 hours was identified in the low-dose ketamine infusion group, (mean standard deviation 1.64 95 % CI: 0.38 to 2.90) which did not reach clinical significance. A lower pain level and less use of opioids was identified in the low-dose ketamine infusion group.&#x0D; Conclusion: Low quality evidence was found, suggesting that low-dose ketamine infusions are not associated with significant changes in blood pressure or heart rate 24 – 48 hours after surgery. It is important to individualize cardiovascular risk for each case, before initiating treatment.

Abstract 16270: Pulse Pressure Amplification Contributes to the Exaggerated Peripheral Blood Pressure Response to Exercise in Patients With HFpEF

Background: Patients with suspected heart failure and preserved ejection fraction (HFpEF) undergo invasive (right heart catheterization) cardiopulmonary exercise testing (iCPET) to confirm diagnosis. During iCPET peripheral arterial blood pressure (BP) is measured using a brachial cuff or radial arterial catheter. Notably, peripheral BP is typically higher than central BP and this difference is assessed by measuring pulse pressure amplification (PPA; peripheral - central PP; PP = systolic BP [SBP] - diastolic BP). The effect of PPA on the assessment of (exaggerated) exercise BP in HFpEF is unknown. Methods: 20 patients with HFpEF (75% Female; age: 69±7 years, BMI: 38±7 kg/m 2 ) were studied at rest and during submaximal and maximal cycling exercise. We measured radial BP (arterial catheterization) and derived ascending aortic BP using a transfer function applied to radial arterial waveforms (SphygmoCor). Pulse pressure amplification was assessed as radial-aortic pulse pressure. Data were compared with one-way and two-way (Site*Exercise Stage) ANOVA. Results: The increase in radial PP with exercise was greater than aortic PP (Site*Stage P&lt;0.001; Figure A); thus, PPA increased with exercise (ANOVA, P =0.001; Figure B). The increase in PPA was due to a greater increase in radial compared to aortic SBP (Site*Stage P=0.002; Figure C). The change in diastolic pressure was not different between sites (Figure D). Increases in PPA accounted for ~30% of the increase in radial SBP. The incidence of exaggerated exercise SBP (Male: &gt;210 mmHg; Female: &gt;190 mmHg) was higher in the radial artery compared to aorta (95 vs 40 %, χ2&lt;0.001). Conclusion: Peak exercise SBP was ~50 mmHg greater in the radial artery compared to aorta. The marked overestimation of central BP during exercise when measuring peripheral BP leads to misguided interpretation of BP responses to exercise, the magnitude of afterload and has implications for the assessment of ventricular-arterial coupling.

Cardioprotective Action of a Novel Synthetic 19,20-EDP Analog Is Sirt Dependent.

Mounting evidence suggests that cytochrome P450 epoxygenase-derived metabolites of docosahexaenoic acid, called epoxydocosapentaenoic acids (EDPs), limit mitochondrial damage after cardiac injury. In particular, the 19,20-EDP regioisomer has demonstrated potent cardioprotective action. Thus, we investigated our novel synthetic 19,20-EDP analog SA-22 for protection against cardiac ischemia-reperfusion (IR) injury. Isolated C57BL/6J mouse hearts were perfused through Langendorff apparatus for 20 minutes to obtain baseline function, followed by 30 minutes of global ischemia. Hearts were then treated with vehicle, 19,20-EDP, SA-22, or SA-22 with the pan-sirtuin inhibitor nicotinamide or the SIRT3-selective inhibitor 3-(1H-1,2,3-triazol-4-yl) pyridine (3-TYP) at the start of 40 minutes reperfusion (N = 5-8). We assessed IR injury-induced changes in recovery of myocardial function, using left ventricular developed pressure and systolic and diastolic pressure change. Tissues were assessed for electron transport chain function, SIRT1 and SIRT3, optic atrophy type 1, and caspase-1. We also used H9c2 cells in an in vitro model of hypoxia/reoxygenation injury (N = 3-6). Hearts perfused with SA-22 had significantly improved postischemic left ventricular developed pressure, systolic and diastolic recovery (64% of baseline), compared with vehicle control (15% of baseline). In addition, treatment with SA-22 led to better catalytic function observed in electron transport chain and SIRT enzymes. The protective action of SA-22 resulted in reduced activation of pyroptosis in both hearts and cells after injury. Interestingly, although nicotinamide cotreatment worsened functional outcomes, cell survival, and attenuated sirtuin activity, it failed to completely attenuate SA-22-induced protection against pyroptosis, possibly indicating EDPs exert cytoprotection through pleiotropic mechanisms. In short, these data demonstrate the potential of our novel synthetic 19,20-EDP analog, SA-22, against IR/hypoxia-reoxygenation injury and justify further development of therapeutic agents based on 19,20-EDP.

IDegLira for type 2 diabetes: a systematic review and meta-analysis.

IDegLira is a novel fixed-ratio soluble combination of insulin degludec and the glucagon-like peptide-1 receptor agonist (GLP-1RA) liraglutide approved for type 2 diabetes (T2D) patients. Individual trials have assessed the clinical profile of IDegLira vs different comparators. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of IDegLira for T2D. PubMed, Embase, Cochrane Library and ClinicalTrials.gov were searched from inception to August 15, 2023. The primary outcomes included change from baseline in haemoglobin A1c (HbA1c) and body weight. Risk ratios (RR), mean differences (MD), and 95% confidence intervals (CI) were calculated to evaluate the outcomes. This meta-analysis identified 1044 citations, and included 13 eligible trials, enroling 7773 patients. Compared with the control groups, IDegLira was optimal in change in HbA1c, percentage of patients achieving HbA1c < 7%, percentage of patients achieving HbA1c < 6.5%, HbA1c < 7.0% without weight gain and without severe or blood glucose (BG)-confirmed hypoglycaemia episodes, HbA1c < 6.5% without weight gain and without severe or BG-confirmed hypoglycaemia episodes, change in fasting plasma glucose, change in self-measured plasma glucose, change in systolic pressure, and total daily insulin dose. No difference was found between the IDegLira and control groups in terms of change in body weight, change in diastolic pressure, severe or BG-confirmed symptomatic hypoglycaemia, nocturnal severe or BG-confirmed symptomatic hypoglycaemia, adverse events or serious adverse events. In patients with T2D, IDegLira improved glycaemic control whilst balancing out risk for hypoglycaemia and gastrointestinal side effects.

Aortic stiffness contributes to greater pressor responses during static hand grip exercise in healthy young and middle-aged normotensive men.

Central arterial stiffness can influence exercise blood pressure (BP) by increasing the rise in arterial pressure per unit increase in aortic inflow. Whether central arterial stiffness influences the pressor response to isometric handgrip exercise (HG) and post-exercise muscle ischemia (PEMI), two common laboratory tests to study sympathetic control of BP, is unknown. We studied 46 healthy non-hypertensive males (23 young and 23 middle-aged) during HG (which increases in cardiac output [Q̇c]) and isolated metaboreflex activation PEMI (no change or decreases in Q̇c). Aortic stiffness (aortic pulse wave velocity [aPWV]; applanation tonometry via SphygmoCor) was measured during supine rest and was correlated to the pressor responses to HG and PEMI. BP (photoplethysmography) and muscle sympathetic nerve activity (MSNA) were continuously recorded at rest, during HG to fatigue (35% maximal voluntary contraction) and 2-min of PEMI. aPWV was higher in middle-aged compared to young males (7.1±0.9 vs 5.4±0.7m/s, P<0.001). Middle-aged males also exhibited greater increases in systolic pressure (∆30±11 vs 10±8mmHg) and MSNA (∆2313±2006 vs 1387±1482%/min) compared to young males during HG (both, P<0.03); with no difference in the Q̇c response (P=0.090). Responses to PEMI were not different between groups. Sympathetic transduction during these stressors (MSNA-diastolic pressure slope) was not different between groups (P>0.341). Middle-aged males displayed a greater increase in SBP per unit change of Q̇c during HG (∆SBP/∆Q̇c; 21±18 vs 6±10mmHg/L/min, P=0.004), with a strong and moderate relationship between the change in systolic (r=0.53, P<0.001) and diastolic pressure (r=0.34, P=0.023) and resting aPWV, respectively; with no correlation during PEMI. Central arterial stiffness can modulate pressor responses during stimuli associated with increases in cardiac output and sympathoexcitation in healthy males.

An Implantable Wireless System for Remote Hemodynamic Monitoring of Heart Failure Patients.

This article presents an implantable wireless system for remote hemodynamic monitoring, which enables direct, continuous (24/7), and simultaneous measurement of pulmonary arterial pressure (PAP) and cross-sectional area (CSA) of the artery. The implantable device, which measures 3.2 mm × 2 mm × 10 mm, comprises a piezoresistive pressure sensor, an ASIC implemented in 180-nm CMOS, a piezoelectric ultrasound (US) transducer, and a nitinol anchoring loop. An energy-efficient pressure monitoring system, which employs duty-cycling and spinning excitation technique, achieves 0.44 mmHg resolution in a pressure range from -135 mmHg to +135 mmHg and consumes 1.1 nJ conversion energy. The artery diameter monitoring system utilizes the inductive characteristic of the implant's anchoring loop and achieves 0.24 mm resolution within a diameter range of 20 mm to 30 mm, four times higher than echocardiography lateral resolution. The wireless US power and data platform enables simultaneous power and data transfer employing a single piezoelectric transducer in the implant. The system is characterized with an 8.5 cm tissue phantom and achieves a US link efficiency of 1.8%. The uplink data is transmitted by using an ASK modulation scheme parallel to the power transfer and achieves a modulation index of 26%. The implantable system is tested in an in-vitro experimental setup, which emulates the arterial blood flow, and accurately detects fast pressure peaks for systolic and diastolic pressure changes at both 1.28 MHz and 1.6 MHz US powering frequencies, with corresponding uplink data rates of 40 kbps and 50 kbps.

Hemodynamic Assessment in Takotsubo Syndrome

BackgroundTakotsubo syndrome (TTS) is a reversible form of heart failure with incompletely understood pathophysiology. ObjectivesThis study analyzed altered cardiac hemodynamics during TTS to elucidate underlying disease mechanisms. MethodsLeft ventricular (LV) pressure–volume loops were recorded in 24 consecutive patients with TTS and a control population of 20 participants without cardiovascular diseases. ResultsTTS was associated with impaired LV contractility (end-systolic elastance 1.74 mm Hg/mL vs 2.35 mm Hg/mL [P = 0.024]; maximal rate of change in systolic pressure over time 1,533 mm Hg/s vs 1,763 mm Hg/s [P = 0.031]; end-systolic volume at a pressure of 150 mm Hg, 77.3 mL vs 46.4 mL [P = 0.002]); and a shortened systolic period (286 ms vs 343 ms [P < 0.001]). In response, the pressure–volume diagram was shifted rightward with significantly increased LV end-diastolic (P = 0.031) and end-systolic (P < 0.001) volumes, which preserved LV stroke volume (P = 0.370) despite a lower LV ejection fraction (P < 0.001). Diastolic function was characterized by prolonged active relaxation (relaxation constant 69.5 ms vs 45.9 ms [P < 0.001]; minimal rate of change in diastolic pressure –1,457 mm Hg/s vs –2,192 mm Hg/s [P < 0.001]), whereas diastolic stiffness (1/compliance) was not affected during TTS (end-diastolic volume at a pressure of 15 mm Hg, 96.7 mL vs 109.0 mL [P = 0.942]). Mechanical efficiency was significantly reduced in TTS (P < 0.001) considering reduced stroke work (P = 0.001), increased potential energy (P = 0.036), and a similar total pressure–volume area compared with that of control subjects (P = 0.357). ConclusionsTTS is characterized by reduced cardiac contractility, a shortened systolic period, inefficient energetics, and prolonged active relaxation but unaltered diastolic passive stiffness. These findings may suggest decreased phosphorylation of myofilament proteins, which represents a potential therapeutic target in TTS. (Optimized Characterization of Takotsubo Syndrome by Obtaining Pressure Volume Loops [OCTOPUS]; NCT03726528)

Decentering and baroreflex sensitivity in adults with elevated blood pressure

Previous studies have linked the ability to decenter, a non-judgmental view of emotions, with lower arterial stiffness and better nocturnal blood pressure dipping in adults. It is unknown however if autonomic regulation of blood pressure is linked to decentering. Therefore, the purpose of this study was to determine if decentering ability is related to cardiovagal or sympathetic baroreflex sensitivity. Thirty-three adults (age 25±6 years; BMI 25±3 kg/m2) with resting blood pressure ≥120/80 mmHg volunteered for this study. All participants had a BMI &lt;30 kg/m2, and had no history of smoking, diabetes, or prescriptions for blood pressure or cardiac function. Participants completed an 11-item experiences questionnaire to evaluate decentering, and then were equipped for a supine autonomic evaluation. The autonomic evaluation included continuous recording of heart rate via 3-lead ECG, muscle sympathetic nerve activity (MSNA) via microneurography, and beat-to-beat blood pressure via finger photoplethysmography. Cardiovagal baroreflex sensitivity (n=33) included estimation of vagal activation by evaluating up-up relationships between systolic arterial pressure (SAP) and R-R intervals of the ECG. Vagal withdrawal was also estimated via the down-down relationships between SAP and R-R intervals. Spontaneous sympathetic baroreflex sensitivity (n=26) was evaluated by evaluating the relationship between changes in diastolic arterial pressure (DAP) in 3 mmHg bins vs. changes in MSNA burst incidence (i.e., bursts / 100 heart beats). Results from 2-tailed Pearson correlation analyses revealed that there was not a relationship between decentering and vagal activation (r=-0.07; p=0.71) or between decentering and vagal withdrawal (r=-0.28; p=0.12). Likewise, there was no relationship between decentering and sympathetic baroreflex sensitivity (r=0.10; p=0.64). Our findings suggest that there is not a clear link between decentering and autonomic regulation of blood pressure as estimated through both cardiovagal and baroreflex sensitivity. NIH (1R15HL140596-01); Nils K. Nelson Endowment Fund This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Assessing Correlation Between Thoracic Impedance and Remotely Monitored Pulmonary Artery Pressure in Chronic Systolic Heart Failure.

Heart failure (HF) readmission continues to be a major health problem. Monitoring pulmonary artery pressure (PAP) and thoracic impedance (TI) are the two modalities utilized for early identification of decompensation in HF patients. We aimed to assess the correlation between these two modalities in patients who simultaneously had both the devices. Patients with history of New York Heart Association class III systolic HF with a pre-implanted intracardiac defibrillator (ICD) capable of monitoring TI and pre-implanted CardioMEMs™ remote HF monitoring device were included. Hemodynamic data including TI and PAPs were measured at baseline and then weekly. Weekly percentage change was then calculated as: Weekly percentage change = (week 2 - week1)/week 1 × 100. Variability between the methods was expressed by Bland-Altman analysis. Significance was determined as a P-value < 0.05. Nine patients met the inclusion criteria. There was no significant correlation between the assessed weekly percentage changes in pulmonary artery diastolic pressure (PAdP) and TI measurements (r = -0.180, P = 0.065). Using Bland-Altman analytic methods, both methods had no significant difference in agreement (0.011±0.094%, P = 0.215). With the linear regression model applied for Bland-Altman analysis, the two methods appeared to have proportional bias without agreement (unstandardized beta-coefficient of 1.91, t 22.9, P ≤ 0.001). Our study demonstrated that variations exist between measurement of PAdP and TI; however, there is no significant correlation between weekly variations between them.

360 CARDIOMEMS HF SYSTEM: CONTINUOUS REMOTE MONITORING FOR OPTIMIZE HF PATIENTS' MANAGEMENT AND RESOURCES CONSUMPTION

Abstract Background Heart failure (HF) alternates phases of stability and phases of exacerbation, with a progressive decline in the patient's functional capacity and quality of life; the need to anticipate and improve the effectiveness of management of HF exacerbation has led to the development of several remote monitoring tools. We report our experience with CardioMEMS HF system (implantable device to monitor changes in pulmonary artery diastolic pressure (PAPd) as early indicator of the onset of worsening HF) in order to optimize the pharmaceutical treatments strategy (e.g. Levosimendan infusion) and to assess the impact on hospital resources consumption and costs. Methods We enrolled 7 patients (69.00±4.88 years; 30% female) with end-stage HF, implanted with CardioMEMS and daily monitored remotely, in order to optimize both tailored adjustment of home therapy and infusions of Levosimendan. More in detail, if the cardiologist detected a tendency for PAPd to rise, patients were contacted for home therapeutic changes. If no further changes were possible, the patient was hospitalized for the infusion of Levosimendan. In order to calculate the impact of this remote monitoring strategy on resources consumption, we collected data on hospitalizations (e.g. causes, numbers, length, high-cost drugs and costs) taking into account the same number of months pre and post-CardioMEMS implant for each patient. Results Following the implantation of CardioMEMS we observed a 45% reduction in the total number of hospitalizations and a 62% reduction in the days of hospitalization (from a total of 421 days before implantation to a total of 159 days post implantation in the observation period). From an economic point of view, a significant hospital cost reduction was recorded in terms of both hospitalization costs (HF related re-hospitalization and CardioMEMS's implant related cost) and drugs infusion costs (hospital stay and drug costs); more specifically, the total savings for the 7 patients are around € 236,000 and total days of hospitalization avoided are around 500 days including the hospitalizations avoided for drugs infusion. Accordingly, was recorded an improvement in patients’ quality of life measured with EQ5D (pre-implantation 75.17±2.06 vs post-implantation 108.60±8.70, p 0.0078). Conclusions Our preliminary results support the usefulness of this system in the remote management of the HF patients and in the re-hospitalization reduction both for exacerbation and drug management. In fact, the parameters’ monitoring through the CardioMEMS device allows a personalized management of drug therapy; more precisely, considering the drug Levosimendan, instead of a periodic standard timing for infusion, a patient-tailored timing of infusion was applied. In conclusion, our innovative strategy contributes to achieve the organizational efficiency of the healthcare facilities, as well as to the adequate use and allocation of financial and human resources with a better outcome for HF patients.

Abstract 14195: The Effects of Pulmonary Capillary Wedge Pressure (PCWP) Reduction on Starling Mechanisms in Heart Failure With Preserved Ejection Fraction (HFpEF): Potential for Harm?

Introduction: Elevated left ventricular (LV) filling pressure during exercise is a pathognomonic characteristic of HFpEF. Multiple therapies aiming to reduce filling pressures in HFpEF patients have failed to improve exercise capacity and in some studies, decreased activity levels. The Dynamic Starling Mechanism (DSM) quantifies beat-by-beat modulation of stroke volume (SV) by respiratory-mediated changes in LV filling and provides insight into the efficiency with which changes in LV filling pressure are converted to SV. Low DSM gain reflects inefficient conversion of LV pressures (input) into stroke volume (output). In this study, we examined the effect of sublingual nitroglycerin (NTG; 400μg given q15 minutes) to lower PCWP compared to placebo on DSM. Methods: HFpEF patients (n=11, 7 women; age 73 ± 7 years) were studied seated upright at rest following sublingual administration of placebo or NTG. DSM was quantified by transfer function analyses of beat-by-beat changes in pulmonary artery diastolic pressure (PAD, right heart catheterization as index for PCWP) and SV (Modelflow from radial arterial line waveform, normalized to direct Fick-derived SV) at the prevailing respiratory frequency. Direct Fick SV was calculated as VO2/a-vO2 difference divided by heart rate. Results: Compared to placebo, NTG decreased both SV (Placebo: 53 ml vs NTG: 43 ml, p=0.004) and PAD (Placebo: 15.0 mmHg vs NTG: 13.9 mmHg, p=0.026). The DSM gain was decreased with NTG compared to placebo (0.57 vs 0.82 ml/mmHg, p&lt;0.0001) suggesting a smaller change in SV for a change in filling pressure. Conclusions: Lowering cardiac filling pressures in the seated upright position decreased efficiency of the beat-by-beat Starling mechanism. The results may provide insight into how reducing LV filling pressures impacts stroke volume regulation, potentially leading to decreased exercise tolerance in HFpEF patients.

Sympathetic neural reactivity to the Trier social stress test.

Sympathetic responsiveness to laboratory mental stress is highly variable, making interpretations of its role in stress reactivity challenging. The present study assessed muscle sympathetic nerve activity (MSNA, microneurography) responsiveness to the Trier social stress test (TSST), which employs an anticipatory stress phase, followed by a public speaking and mental arithmetic task. We hypothesized that sympathetic reactivity to the anticipatory phase would offer a more uniform response between individuals due to elimination of confounds (i.e. respiratory changes, muscle movement, etc.) observed during more common stress tasks. Participants included 26healthy adults (11men, 15 women, age: 25±6years, body mass index: 24±3kg/m2 ). Continuous heart rate (electrocardiogram) and beat-to-beat blood pressure (finger plethysmography) were recorded from all participants, while MSNA recordings were obtained in 20 participants. MSNA burst frequency was significantly reduced during anticipatory stress. During the speech, although burst frequency was unchanged, total MSNA was significantly increased. Changes in diastolic arterial pressure were predictive of changes in MSNA during anticipatory (β=-0.680, P=0.001), but not the speech (P=0.318) or mental maths (P=0.051) phases. Lastly, sympathetic reactivity to anticipatory stress was predictive of subsequent reactivity to both speech (β=0.740, P=0.0002) and maths (β=0.663, P=0.001). In conclusion, anticipatory social stress may offer a more versatile means of assessing sympathetic reactivity to mental stress in the absence of confounds and appears to predict reactivity to subsequent mental stress paradigms. KEY POINTS: Cardiovascular reactivity to laboratory mental stress is predictive of future health outcomes. However, reactivity of the sympathetic nervous system to mental stress is highly variable. The current study assessed peripheral muscle sympathetic nerve activity in response to the Trier social stress test, a psychosocial stressor that includes anticipatory stress, public speaking and mental arithmetic. Our findings demonstrate that sympathetic neural activity is consistently reduced during anticipatory stress. Conversely, the classically observed inter-individual variability of sympathetic responsiveness was observed during speech and maths tasks. Additionally, sympathetic reactivity to the anticipatory period accurately predicted how an individual would respond to both speech and maths tasks, outlining the utility of anticipatory stress in future research surrounding stress reactivity. Utilization of the Trier social stress test in autonomic physiology may offer an alternative assessment of sympathetic responsiveness to stress with more consistent inter-individual responsiveness and may be a useful tool for further investigation of stress reactivity.

Platelet-rich plasma exhibits anti-inflammatory effect and attenuates cardiomyocyte damage by reducing NF-κB and enhancing VEGF expression in isoproterenol induced cardiotoxicity model.

The present study investigated the cardioprotective effects of activated platelet-rich plasma (PRP) on high dose isoproterenol (ISO) induced cardiotoxicity. ISO was injected at a dose of 85 mg/kg/day, s.c. for 2 days. Cardiac function parameters including dp/dt max/min, left ventricular end diastolic pressure (LVEDP), relaxation constant (tau) and electrocardiogram (ECG) changes, anti-oxidant and membrane bound enzymes assays, pro-inflammatory cytokine levels, collagen content, immunohistochemical staining/gene expression of vascular endothelial growth factor (VEGF), cTnI (cardiac troponin I), NF-κB (nuclear factor kappa B), Smad-2/3, TGF-β (transforming growth factor), collagen-1/3 proteins were evaluated. PRP and platelet-poor plasma (PPP) were injected intramyocardially (200 μl in each ventricle region) 3 h after first dose of ISO under anesthesia. ISO injection induced cardiac dysfunction, hypertrophy, fibrosis, necrosis due to decline in anti-oxidant capacity, enhanced NF-κB and reduced cTnI immunostaining. However, the PRP injection attenuated these cardiac pathological changes by exerting anti-inflammatory properties and promoting cardiomyocyte repair.

English

BACKGROUND Stress response to intubation produces marked hemodynamic changes during direct laryngoscopy using muscle relaxants. Since attenuation of hemodynamic response to laryngoscopy and tracheal intubation leads to better outcomes, a method for providing good intubating conditions rapidly without using muscle relaxants is being sought. The objective of the present study was to compare the hemodynamic changes occurring while intubating with 2 different doses of propofol. METHODS We compared heart rate, systolic blood pressure, diastolic pressure and mean arterial pressure changes during tracheal intubation with 2 different propofol doses without using muscle relaxants. Intravenous fentanyl inhibits the sympathetic nervous response to direct laryngoscopy and tracheal intubation in both groups of patients and acts as pre-emptive analgesia. RESULTS Comparison of the hemodynamic parameters revealed no statistically significant differences between the low dose propofol (PL) and high dose propofol (PH) groups with regard to heart rate or blood pressure changes at similar intervals postintubation. Both patient groups showed blood pressure fall along with a reflex increase in heart rate at 1 minute to 5 minutes post-intubation, returning to nearbaseline values 10 minutes post-intubation. None of these changes was either clinically detrimental or produced incidents of desaturation or arrhythmias in any study patient. CONCLUSIONS Low dose propofol may be useful in elderly or mildly hypovolemic patients, intolerant to a higher drug dosage whereas, the higher propofol dose may be particularly useful in the adult with a higher muscle mass in situations where muscle relaxant is to be restricted or avoided. KEY WORDS Tracheal Intubation, Hemodynamic Changes, Different Doses Propofol.

The research of correlation between blood pressure and nailfold capillary parameters in exercising and non-exercising pregnant women

Background/Aim: With an increase in cardiac output, blood pressure values in pregnancy increase. The aim of the study was to examine the effect of prenatal exercises on the circulatory parameters and the correlation between blood pressure and nailfold capillary parameters in healthy pregnant women. Methods: The blood pressure shape and length of nailfold capillary were assessed in 35 non-exercising pregnant women and 35 pregnant women who exercised, at the beginning of the study (between 20 and 32 gestational week) and the end of the study (28 - 40 gestational week). Results: The elevation in blood pressure was significantly lower in pregnant women who exercised in relation to non-exercising pregnant women. After eight weeks, the length of the capillary loops was increased by 30 µm and the number of pregnant women with pronounced shape changes of capillary loops increased, with no difference between the groups. Non-exercisers had a correlation between the change in diastolic pressure and the increase in capillary length (r = 0.53, p = 0.001). In the experimental group, the correlation between the change in blood pressure and the increase in the length of capillary loops was not determined. Conclusion: Prenatal physical activity had a beneficial impact on the circulation of pregnant women. In pregnant women in the third trimester, after eight weeks of follow-up, the length of the nailfold capillary loops and the presence of pronounced shape changes of capillary loops were increased, without difference between exercisers and non-exercisers. In non-exercising pregnant women, the capillary length was increased with the elevation of diastolic blood pressure, while the correlation was not found in pregnant women who exercised.

Abstract 13543: Impaired Stroke Volume Response During Exercise in Patients With Heart Failure With Preserved Ejection Fraction (HFpEF): The Role of Dynamic Starling Mechanisms

Introduction: Impaired stroke volume (SV) response during exercise is common in HFpEF. The regulation of SV during low intensity exercise is dependent on end-diastolic volume (EDV) reserve from a compliant left ventricle (LV). The Dynamic Starling Mechanism (DSM) quantifies beat-by-beat modulation of SV by respiratory-mediated changes in LV filling pressure and provides insight into the relationship between changes in LV compliance and SV response during exercise. We hypothesized low SV reserve during exercise would track with greater impairments in DSM gain in HFpEF patients. Methods: 11 HFpEF patients (68 ± 6 years; 7 females) were studied at rest and during 20 Watts of upright cycling and separated into higher or lower SV reserve (direct Fick) groups based on median SV response (&gt; vs ≤ 20% increase). DSM was quantified by transfer function (input/output frequency) analyses of beat-by-beat changes in pulmonary artery diastolic pressure (PAD, right heart catheterization) and SV (modelflow from radial arterial line waveform). Due to the small group size, magnitude of differences (i.e. effect size) between conditions and groups is assessed via Hedges’ g . Results: HFpEF patients with low SV reserve had blunted increases in SV compared to higher SV group patients (Δ 2 vs 31 ml, g = -2.0; Table). Compared to higher SV reserve, the lower SV reserve group exhibited a moderately greater increase in the power spectral density (PSD) of PAD ( g = 0.4) and decrease in PSD-SV ( g = 0.5) from rest to 20W. While both groups decreased DSM gain from rest to exercise, the lower SV reserve group had a greater decline (Δ -1.37 vs -0.61 ml/mmHg, g = -1.2). Conclusion: Lower SV reserve in patients with HFpEF is associated with impaired DSM gain during exercise. The lower gain was a function of increases in PAD PSD and decreases in SV PSD suggesting lower LV compliance and lower EDV reserve during exercise. Impaired DSM may explain low SV response and contribute to exercise limitations in patients with HFpEF.