Take Home Message
- A high association between Mobil O Graph cBP was found in men (r < 0.89) and women ((r < 0.917) as compared with the hemodynamic values.
- EVBA showed the reduction in BP and MSNA without disturbing cardiovascular responses in patients with RHTN.
- Soft computing is being widely used in the medical area to provide diagnoses, in this case the risk of developing hypertension.
- Younger women shows general lower c-f PWV levels than corresponding men.
- Conduction of confirmatory tests is needed in all patients with positive screening test.
- Strict standardization of the conditions under which the ARR is measured was recommended.
1. Central Blood Pressure: Mobile O Graph Validation Versus Invasive Aortic Pressure
New research presented by Sanchez RA on 22 nd June 2019 at the 29th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. This study assessed the specific waveforms procured invasively in the aorta in comparison with the corresponding waveforms gained from a Mobil-O-Graph device and the calculated central blood pressures compared with the aim to authorize the noninvasive central blood pressure computation.
20 patients were included in the study (10 males, 68 ± 12y, BMI: 27.4 ± 4.6Kg/ m 2 and 10 females, 77 ± 8y, BMI: 28.5 ± 5.3Kg/m 2 ), presented for invasive coronary assessments. In the same moment, the Mobil O Graph acquisition data was executed in the hemodynamic study. Both blood pressure waves were digitized and kept for subsequent evaluation and measurements once a single beat was obtained (invasive and non- invasive central pressure). To compare invasive and non-invasive central blood pressure waves, a computerized interpolation procedure was developed in laboratory. All waveforms were normal and no irregularity was observed in their periods. No vasoactive drug was taken during the measurement and usual medications were continued. All data were described as mean ± standard deviation. Unpaired Student t-test and a Bland & Altman approach were used to analyse the examination of invasive and non-invasive central pressure. A p < 0.05 was contemplated as a substantial difference (SPSS software). ‘
A high association between Mobil O Graph cBP was found in men (r < 0.89) and women ((r <0.917) as compared with the hemodynamic values. Additionally, in men and women, mean differences (hemodynamic minus Mobil o Graph) were in the 95% confidence interval and exhibited a normal error distribution. Although the slope of the regression lines (Men: y = 0.7673x + 16.301; Women: y = 0.7874x + 22.008) was lower than 1 in both genders, designating a lower estimation of Mobil O Graph cBP values respective to the hemodynamic ones. It was concluded that there was a high association between cBP and the underestimation of CBP values measured by the Mobil O Graph device either in men or women.
2. The Effect of Endovascular Baroreflex Amplification on Sympathetic Nerve Activity in Patients with Resistant Hypertension: A Proof-of-Mechanism Study
New research presented by van Kleef M on 22 nd June 2019 at the 29 th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. In an uncontrolled first-in-human study, EVBA is a novel device based therapy that presented to reduce blood pressure (BP) in patients with RHTN. It is postulated that BP is reduced at least in part, with obstruction of muscle sympathetic nerve activity (MSNA) by EVBA. But, this has never been investigated. This study assessed the effect of EVBA on MSNA, baroreflex sensitivity (BRS) and sympathetic cardiovascular reactivity.
The endovascular MobiusHD device was unilaterally inserted into the carotid sinus of patients with RHTN (24-hour mean ambulatory systolic BP > 130 mmHg on >=3 antihypertensive medications, including a diuretic) without atherosclerotic carotid disease in a single-center sub-study of the CALM- DIEM study. After a 2-week washout of antihypertensive medications which influenced sympathetic regulation, microneurography and non-invasive continuous BP was measured at baseline and 3 months. Changes in resting MSNA, Valsalva maneuver-evoked cardiac BRS and cardiovascular responses to cold pressor testing (CPT) were estimated.
In the study, 14 patients were incorporated from which 9 patients (mean age 52 (±8) years, 6 males) had paired computations at baseline and 3 months. Two of the 9 paired calculations included MSNA recordings of insufficient quality and one had frequent premature ventricular complexes, leaving 6 pairs available for MSNA analysis, 8 for cardiac BRS examination and 9 for evaluation of sympathetic cardiovascular reactivity. Resting MSNA was reduced from 40 (range 16–71) to 32 (range 5–66) bursts/min, and from 50 (range 21–81) to 40 (range 7–75) bursts/100 heartbeats, after 3 months of EVBA as shown in Table 1. 24-hour mean systolic ambulatory BP showed simultaneous reduction from 156 (range 132–193) mmHg to 146 (range 128–190) mmHg. However, Valsalva maneuver-evoked cardiac BRS and MAP and HR responses to CPT did not altered. It was concluded that EVBA showed the reduction in BP and MSNA without disturbing cardiovascular responses in patients with RHTN. The finding is consistent with reduced effect of central sympathetic drive and may recommend that EVBA increases sympathetic baroreflex restraint without impairing BP regulatory mechanisms.
3. Optimization of an Artificial Neuronal Network for Diagnosis of Develop Hypertension with 7 Risk Factors
New research presented by van Melin P on 22 nd June 2019 at the 29 th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. The research was conducted to provide an accurate and timely diagnosis in order to prevent hypertension, as well as being a simple tool to use and a great help for the cardiologist.
Seven risk factors are considered for training the artificial neural network, these are diastolic pressure, systolic pressure, if have hypertensive parents, if are a smoker or not, age, body mass index and gender. The ANN models the information and learns the behavior of the data, giving as output the percentage of risk that the patient has in developing hypertension in a lapse of four years. In order to improve the results and provide a more accurate diagnosis, optimization of the ANN layers and neurons were performed using the Flower Pollination Algorithm (FPA), in which different experiments are carried out, that provides the least error when is simulated with a test of 250 patients.
Experiments were conducted and ANN best architecture were with 2 hidden layers with 9 and 19 neurons per layer, using the Levenberg-Marquardt method to find the appropriate weights of the neurons, the comparison of the optimized neural network with respect to non-optimized was made, where an improvement in the results is observed because the best architecture of the ANN was found with the FPA optimization algorithm. On comparison of results of the non-optimized and the optimized ANN, it was being observed that by not optimizing the parameters of the ANN throws 7 errors, while the optimized ANN have no errors. It was thus concluded that soft computing is being widely used in the medical area to provide diagnoses, in this case the risk of developing hypertension. When performing the optimization of the artificial neural network, the authors were certain that it will provide an accurate diagnosis, since the architecture has been optimized and probe and provide least error when tested with a set of 250 patients.
4. Family Patterns of Central Haemodynamics across Three Generations In The Malmö Offspring Study
New research presented by Rosberg EP on 23 rd JUNE 2019 at the 29 th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. In recent years, central haemodynamics have appeared as a promising predictor of cardiovascular health and future risk of cardiovascular disease (CVD). Central haemodynamics influenced early in the development of vascular aging and affect organs directly attached to large arteries, such as the brain, kidneys and heart. Indirect measurements that reflect the central haemodynamic and arterial stiffness includes carotid-femoral pulse wave velocity (c-f PWV), augmentation index (Aix) and central systolic blood pressure (cSBP). Various research studies have shown that raised arterial stiffness raises the CVD risk and it also shows positive association between a family history of CVD and arterial stiffness in offspring.
This research study shows association for patterns of central haemodynamics across three related generations (G1-G3) and a gender difference in c-f PWV. Almost, 1131 subjects from Malmö Diet Cancer Study (MDCS) and Malmö Offspring Study (MOS) were included in this research study. c-f PWV was measured in grandparents and in all offspring were included in inclusion criteria. Correlation analyses of c-f PWV between offspring (G1) and c-f PWV in parents (G2) and Grandparents (G3) were assessed. Parents and grandparents were split in quartiles by c-f PWV and offspring c-f PWV and cSBP means were compared with one-way ANOVA analyses. Multiple regression analyses were assessed to adjust for age, sex, BMI, SBP and fasting glucose. By using Kruskal Wallis Test, gender differences were compared.
Offspring c-f PWV was significantly associated with c-f PWV in parents (r = 0.26, p<0.001.) and in grandparents (r = 0.29, p<0.001). c-f PWV in Offspring significantly associated with parental Aix and cSBP. As compared to parents with low c-f PWV, statistically significant higher means of c-f PWV and cSBP in offspring was reported in parents with high c-f PWV. Younger generation of women shows lower c-f PWV as compared to corresponding men, p<0.001. These research data suggest that in this population based study measures of central haemodynamic are positively associated across three generations. Younger women shows general lower c-f PWV levels than corresponding men.
5. Is Confirmatory Testing Needed in All Patients with Positive Screening Test for Primary Aldosteronism?
New research presented by J. Václavík on 23 rd JUNE 2019 at the 29 th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. One of the most common known causes of secondary hypertension is primary hyperaldosteronism (PHA). This research data shows whether confirmatory testing is necessary in all patients with a positive screening test.
A laboratory screening for aldosterone, plasma renin activity and aldosterone renin ratio (ARR) was conducted in ambulatory patients with severe or resistant arterial hypertension. Patients have gone through a confirmatory test after withdrawal of interfering medications with similal laboratory investigations before and after infusion of 2 l of saline for 4 hours in the case of ARR > 30 or aldosterone > 150 ng/L. The results of both estimations were compared with an effort to identify PHA predictors were included in the subsequent statistical analysis. This trial was supported by a grant IGA_LF_2017_029. Almost in 312 participants, Confirmatory testing was conducted.
It was observed that participants with confirmed PHA were more likely to be men (70.3% vs. 54.9%), shows lower serum potassium (3.8 vs. 4.1 mmol/L) and plasma renin activity (0.7 vs. 3.2), higher serum aldosterone (268 vs. 229 ng/L) and ARR (177 vs. 95), higher office systolic blood pressure (147 vs. 143 mmHg), and were using more antihypertensive drugs (4.7 vs. 3.7) (all with p <0.01). it was reported that the screening parameters in the univariate analysis shows significant predictors of PHA: PRA < 0.63 (AUC ROC 0.63), aldosterone >165 ng/L (AUC 0.60), ARR > 43 (AUC 0.68), serum potassium < 4.0 mmol/L (AUC 0.68) and the number of used antihypertensive drugs >4 (AUC 0.64), all with p <0.01. The combination of the recommended cut-off values of screening test for further non-testing recommended in the international guidelines (aldosterone >200 ng/L and potassium <4.0 mmol/L) shows an overall accuracy for the diagnosis of PHA of only 69.0%. A combination of an ARR > 43 and serum potassium < 4 mmol/L shows overall accuracy for PHA of 75.6%. The prediction of the diagnosis of primary hyperaldosteronism from the results of screening test is not entirely accurate. Therefore, Conduction of confirmatory tests is needed in all patients with positive screening test.
6. The Influence of Confounders on the Aldosterone-to-Renin Ratio as a Screening Test for Primary Hyperaldosteronism: A Systematic Analysis of the Literature
New research presented by Veldhuizen G on 23 rd JUNE 2019 at the 29 th European Meeting on Hypertension and Cardiovascular Protection, Milan, Italy. Currently, for primary hyperaldosteronism (PA), the aldosterone-to-renin ratio (ARR) is widely used as a screening test. Nonetheless, many factors could variably influence the levels of renin and/or aldosterone and potentially induce inaccurate screening of PA.
This research study was estimated to identify these factors and the magnitude of their effect on the ARR. Using standardized methods, a systematic PubMed and Cochrane literature search looking at patient characteristics that may influence the aldosterone or renin values and the ARR were performed. These divided into assay-related factors and patient- related factors such as age, posture, salt intake etc. To what extent factor variability could modify sensitivity, specificity and, if possible, the predictive value of the ARR was evaluated for each factor. This literature-review initially identified 428 articles which were scrutinized for eligibility.
A total of 55 articles proved suitable for inclusion in this analysis after careful selection on the basis of a number of prespecified criteria. It was also reported that differences in assay techniques shows no appreciable effects but gender, age, race, body mass index, posture, sodium intake and time of day shows a significant impact on the test results. However, only a few antihypertensive drugs shows their effect on the ARR assessed, beta blockers, ARBs, ACE-Is, spironolactone, and amlodipine seem to have impact on the ARR the most, whereas moxonidine and a few calcium antagonists shows negligible effect. There are several factors that affect the ARR in such a way that it may result in misinterpretation of the ARR. In addition, regarding the influence of antihypertensive drugs very little information is available. Hence, strict standardization of the conditions under which the ARR is measured was recommended.
