Cardiac acoustic biomarkers as surrogate markers to diagnose the phenotypes of pulmonary hypertension: an exploratory study

Pulmonary hypertension (PH) is commonly associated with left heart disease. In this retrospective study, using the database of a clinical study conducted between January 2008 and July 2008, the phenotypes of PH were classified using non-invasive cardiac acoustic biomarkers (CABs) and compared with classification by echocardiography. Records with same-day measurement of acoustic cardiography and right heart catheterization (RHC) parameters were included; cases with congenital heart disease were excluded. Using the RHC measurements, PH was classified as pre-capillary PH (Prec-PH), isolated post-capillary PH (Ipc-PH), and combined pre-capillary and post-capillary PH (Cpc-PH). The first, second, third, and fourth heart sounds (S1, S2, S3, and S4) were quantified as CABs (intensity, complexity, and strength). Forty subjects were selected: 5 had Prec-PH, 5 had Ipc-PH, 8 had Cpc-PH, and 22 had No-PH. CABs were significantly correlated with RHC measurements, with significant differences among phenotypes. Phenotype classification was performed using various CABs, and the diagnostic performance as assessed by the area under the receiver operating characteristic curve was 0.674–0.720 for Prec-PH, 0.657–0.807 for Ipc-PH, and 0.742 for Cpc-PH. High negative and low positive predictive values for phenotype identification were observed. CABs may provide an ambulatory measurement method with home-monitoring friendliness which is more convenient than standard examinations to identify presence of PH and its phenotypes.

Prevalence and Characteristics of Blood Pressure Phenotypes in Patients with Hypertension and Chronic Respiratory Diseases (Study of Ambulatory Practice Data of a Cardiologist)

Diagnosis of the blood pressure (BP) phenotype is the most important indication for its ambulatory measurement because BP phenotype is associated with cardiovascular complications and death. The study of BP phenotypes is important for patients with hypertension (HT) and comorbidity, including asthma and chronic obstructive pulmonary disease (COPD). The combination of HT with these lower airway diseases (LAD) leads to the mutual influence of pathologies creates difficulties in the drugs choice and may affect BP phenotype in HT patients.Aim. To compare in the prospective investigation various characteristics of BP phenotype in HT patients considering LAD (asthma or COPD).Material and methods. The prospective cohort study of ambulatory patients with HT (n=156) was carried out. The part of these patients had asthma or COPD (n=69). The clinical measurements and 24-hour BP monitoring, spirometry, clinical and biochemical blood tests, standard examination were performed, initially and after 12 months. BP phenotype were determined by the ratio of clinical BP and ambulatory BP considering their threshold values. Standard statistical methods and multivariate analysis were used.Results. Patients with LAD had 2 times more often prognostically unfavorable phenotypes: ineffective antihypertensive therapy (AHT) 37.3% vs 15.7% and masked AHT inefficiency 7.5% vs 4.5%; white coat HT on treatment (WCH) and effective AHT were less common(29.9% vs 42.7%; 25.5% vs 37.1%, respectively, p 148 mm Hg (b=2.733, p=0.040), LAD (b=1.015, p=0.011), serum total cholesterol (b=0.350, p=0.043), degree of nighttime diastolic BP decrease (for 13.1-18.0% b=-2.130, p=0.004; for 18.1-24.0% b=-2.509, p=0.001). The factors associated with masked AHT inefficiency in comparison to effective AHT were heart rate in orthostasis >87 beats/min(b=3,512, p=0.006) and SBP in orthostasis 141-148 mm Hg (b=3.405, p=0.004).Conclusion. The prevalence of prognostically unfavorable BP phenotypes (ineffective AHT and masked AHT inefficiency) is two times higher in HT patients with LAD. The first is associated with LAD presence, sex, and serum cholesterol; both phenotypes interrelated with hemodynamic parameters including degree of nighttime diastolic BP decrease. We found no association between AHT and LAD therapy with the BP phenotypes in this study. However, larger works in this area are required, including analysis of outcomes in long-term prospective studies.

Behavioural Evaluation of a Leash Tension Meter Which Measures Pull Direction and Force during Human–Dog On-Leash Walks

Leash tension forces exerted by dog and handler during walks affect their welfare. We developed a novel ambulatory measurement device using a load cell and a tri-axial accelerometer to record both the tension and direction of forces exerted on the leashes. Data were relayed telemetrically to a laptop for real time viewing and recording. Larger and heavier dogs exerted higher leash tension but had a lower pulling frequency than their smaller and lighter conspecifics. This pattern was observed in the reactional forces of handlers. Young dogs pulled more frequently during walks, which was also mirrored in handlers’ pulling. Well-behaved dogs created lower leash tension, but handlers did not respond with lower forces. This novel method of recording leash tension will facilitate real-time monitoring of the behaviour of dogs and their handlers during walks.

Evolution of ambulatory measurement for the detection of heart diseases

Since the appearance of the Holter monitor, it was conceived as a continuation of the electrocardiogram which serves to detect cardiac diseases, many signs of progress have been made of these devices, which go hand in hand with technology, mainly in elements microcontrollers and micro sensors, such as the transmission of data in real time. With this has been minimized the shortcomings to provide greater comfort and better results of the analysis. This article contains an analysis of these ambulatory measuring devices from the beginning to the current research, analyzing the use of this element for the detection of cardiac diseases, pros and cons of this kind of devices by emphasizing great change that has been generated in recent years with the technological progress.