Evaluation of Left Ventricular Systolic Function and Mass in Primary Hypertensive Patients by Echocardiography

The role of diagnostic modalities in differentiating hypertensive heart disease and hypertrophic cardiomyopathy: strategies in adults for potential application in paediatrics

Hypertensive heart disease and hypertrophic cardiomyopathy both lead to left ventricular hypertrophy despite differing in aetiology. Elucidating the correct aetiology of the presenting hypertrophy can be a challenge for clinicians, especially in patients with overlapping risk factors. Furthermore, drugs typically used to combat hypertensive heart disease may be contraindicated for the treatment of hypertrophic cardiomyopathy, making the correct diagnosis imperative. In this review, we discuss characteristics of both hypertensive heart disease and hypertrophic cardiomyopathy that may enable clinicians to discriminate the two as causes of left ventricular hypertrophy. We summarise the current literature, which is primarily focused on adult populations, containing discriminative techniques available via diagnostic modalities such as electrocardiography, echocardiography, and cardiac MRI, noting strategies yet to be applied in paediatric populations. Finally, we review pharmacotherapy strategies for each disease with regard to pathophysiology.

Application of Echocardiography in Anaesthesia: From Preoperative Risk Assessment to Postoperative Care

Echocardiography has carved out a fundamental niche in anaesthesiology, revolutionizing the monitoring and management of cardiac function during surgery. Clinical practice has changed from simple 2D and 3D echocardiography to more sophisticated applications such as incorporating artificial intelligence. Echocardiography provides detailed real-time information about cardiac anatomy and function, helping anaesthesiologists make better decisions regarding tailoring anesthetic interventions and optimizing patient outcomes. From optimizing hemodynamic management in patients with severe aortic stenosis to fine-tuning fluid and vasopressor therapy in patients with right heart dysfunction, echocardiography has improved the care provided in the perioperative period. These applications permit the demonstration of not only technical advantages that could accrue from echocardiography but are also a part of individualized care to improve the outcomes of patients. The challenges in integrating echocardiography with anaesthesia include operator dependency, a steep learning curve in acquiring echocardiographic skills, and limitations due to patient factors and technological limitations, which lead to poor echocardiographic performance. Additionally, transoesophageal echocardiography (TEE) is an invasive procedure with several potential risks that must be considered cautiously. Continuing education, certification recommendations, and skill development are prerequisites for this echocardiography tool to remain robust and reliable in anaesthesiology. Technological innovation, especially in improving 3D imaging and integration with artificial intelligence, is where a very bright future lies ahead for echocardiography. It would further accelerate the process of echocardiographic evaluation and improve diagnostic accuracy. All these would turn out to be more person-centered for each patient. Anaesthesiologists must, therefore, pace themselves with such developments so these can be appropriately applied in the clinics. In summary, echocardiography became so integrally ingrained into anaesthesia that it propelled the specialty with essential tools anaesthesiologists use to manage patients for optimum outcomes. Its application has difficulties and limitations, but continued professional development and development of echocardiographic technology will make sure that its benefits are maximized. Quickly, echocardiography is becoming central to anaesthesiology's role in optimizing patient care and surgical success as we move into the application of evermore sophisticated echocardiographic techniques.

Beat-by-Beat Estimation of Hemodynamic Parameters in Left Ventricle Based on Phonocardiogram and Photoplethysmography Signals Using a Deep Learning Model: Preliminary Study

Beat-by-beat monitoring of hemodynamic parameters in the left ventricle contributes to the early diagnosis and treatment of heart failure, valvular heart disease, and other cardiovascular diseases. Current accurate measurement methods for ventricular hemodynamic parameters are inconvenient for monitoring hemodynamic indexes in daily life. The objective of this study is to propose a method for estimating intraventricular hemodynamic parameters in a beat-to-beat style based on non-invasive PCG (phonocardiogram) and PPG (photoplethysmography) signals. Three beagle dogs were used as subjects. PCG, PPG, electrocardiogram (ECG), and invasive blood pressure signals in the left ventricle were synchronously collected while epinephrine medicine was injected into the veins to produce hemodynamic variations. Various doses of epinephrine were used to produce hemodynamic variations. A total of 40 records (over 12,000 cardiac cycles) were obtained. A deep neural network was built to simultaneously estimate four hemodynamic parameters of one cardiac cycle by inputting the PCGs and PPGs of the cardiac cycle. The outputs of the network were four hemodynamic parameters: left ventricular systolic blood pressure (SBP), left ventricular diastolic blood pressure (DBP), maximum rate of left ventricular pressure rise (MRR), and maximum rate of left ventricular pressure decline (MRD). The model built in this study consisted of a residual convolutional module and a bidirectional recurrent neural network module which learnt the local features and context relations, respectively. The training mode of the network followed a regression model, and the loss function was set as mean square error. When the network was trained and tested on one subject using a five-fold validation scheme, the performances were very good. The average correlation coefficients (CCs) between the estimated values and measured values were generally greater than 0.90 for SBP, DBP, MRR, and MRD. However, when the network was trained with one subject's data and tested with another subject's data, the performance degraded somewhat. The average CCs reduced from over 0.9 to 0.7 for SBP, DBP, and MRD; however, MRR had higher consistency, with the average CC reducing from over 0.9 to about 0.85 only. The generalizability across subjects could be improved if individual differences were considered. The performance indicates the possibility that hemodynamic parameters could be estimated by PCG and PPG signals collected on the body surface. With the rapid development of wearable devices, it has up-and-coming applications for self-monitoring in home healthcare environments.

Evaluation of Left Ventricular Mass in Different Cardiac Geometry Using Three-Dimensional Contrast-Enhanced Echocardiography

A total of 69 patients were enrolled in the study, including 23 patients with hypertrophic cardiomyopathy (HCM), 26 patients with Left Ventricle (LV) enlargement comprising 16 dilated cardiomyopathy (DCM) patients and 10 ischemic cardiomyopathy (ICM) patients, and 20 control subjects. All patients underwent 2DE, contrast-enhanced 2DE (Contrast-2DE), 3DE, Contrast-3DE, and single photon emission computed tomography (SPECT) examinations. The 2DE-AL and 3DE methods measured the left ventricular mass (LVM). The results were compared with those measured by SPECT. The measured LVM of the 69 patients was systematically overestimated by 2DE-AL (177.4 ± 56.2 g), Contrast-2DE-AL (174.5 ± 55.5 g), 3DE (167.3 ± 59.2 g), and Contrast-3DE (154.2 ± 46.7 g) when compared with SPECT (148.5 ± 52.4 g) (P < 0.05), while Contrast-3DE provided the best agreement with SPECT in LVM measurement (r = 0.898, P < 0.001) and had the smallest deviation (5.7 ± 23.1 g). 3DE overestimated LVM more compared to Contrast-3DE in LV hypertrophy group (165.5 ± 37.9 g versus 153.5 ± 27.6 g, P = 0.003) and LV enlargement group (204.5 ± 69.3 g versus 183.5 ± 53.5 g, P = 0.006). For 2DE methods, there was no significant difference between the LVM obtained with or without contrast enhancement in control group (132.3 ± 23.6 g versus 128.4 ± 23.3 g), LV hypertrophy group (177.7 ± 38.6 versus 178.3 ± 30.9 g, P = 0.889), and LV enlargement group (211.9 ± 63.2 g versus 206.5 ± 66.0 g, P = 0.386). The difference between LVM measured by 2DE-AL and SPECT was the greatest (27.9 ± 34.0 g), especially in LV hypertrophy group and LV enlargement group (LV hypertrophy group 39.7 ± 26.0 g; LV enlargement group 24.2 ± 42.8 g). To conclude, Contrast-3DE and SPECT show greater consistency in LVM measurement, especially in cardiomyopathy, when compared with 2DE. Administering contrast can effectively reduce the overestimation of LVM by non-contrast DE.

Speckle Tracking Echocardiography Verified the Efficacy of Qianyangyuyin Granules in Alleviating Left Ventricular Remodeling in a Hypertensive Rat Model

Background

Global longitudinal strain (GLS) can be assessed by speckle tracking echocardiography (STE) to express the degree of cardiac fibrosis. Qianyangyuyin (QYYY) granules can effectively improve GLS in hypertensive patients. Using a hypertensive rat model, we carried out speckle tracking echocardiography to validate the effect of QYYY in diminishing LV remodeling.

Methods

We randomly divided 16 spontaneously hypertensive rats (SHRs) into SHR, SHR + valsartan (SHR + V), SHR + low-dose QYYY (SHR + QL), and SHR + high-dose QYYY (SHR + QH) groups, with four rats in each group. Another group of 4 Wistar-Kyoto (WKY) rats were selected into a normal control (WKY) group. At the 8th week, conventional echocardiographic parameters were measured by GE Vivid E95 ultrasound (12S probe, 10-12 MHz) and GLS by speckle tracking echocardiography with EchoPAC (version 203) software. HE and Masson's trichrome staining were performed to detect the cardiomyocyte width and collagen volume fraction after rat sacrifice. Collagen I, α-SMA, S100A4, TGF-β, Smad 3, MYH6, and MYH7 were further analyzed by Western blot.

Results

The absolute values of GLS significantly increased in the SHR + QH group compared to the SHR group, while the CVF and CW values significantly decreased. In addition, Collagen I, α-SMA, S100A4, TGF-β, Smad3, MYH7, and MYH7/MYH6 ratio remarkably reduced in the SHR + QH group. The value of GLS could be repetitively measured and positively correlated with the collagen volume fraction of the myocardium and the cardiomyocyte width of the left ventricular free wall.

Conclusions

GLS is a reliable indicator to evaluate the therapeutic effect on left ventricular remodeling in hypertension. QYYY granules can inhibit the development of cardiac fibrosis in the hypertensive rat model.

Four-Dimensional Volume-Strain Expression in Asymptomatic Primary Hypertension Patients Presenting with Subclinical Left Atrium-Ventricle Dysfunction

OBJECTIVE

The purpose of this study was to evaluate the different components of left atrial (LA) dysfunction predictors in asymptomatic primary systemic hypertension patients with preserved left ventricular (LV) ejection fraction, particularly using LA 4-dimensional (4D) longitudinal and circumferential strain values.

METHODS AND RESULTS

Patients with no left ventricular hypertrophy (NLVH) and left ventricular hypertrophy (LVH) are all asymptomatic regarding primary blood hypertension. Thirty NLVH patients and 30 LVH patients according to LV mass index and 40 controls analyzed by 4D echocardiography were prospectively enrolled. LA volumes and longitudinal and circumferential strains were measured using 4D volume-strain echocardiography with a Vivid E95 Version 203 instrument. Correlation analysis indicated a significant relation between LV 4D mass index and LA 4D longitudinal/circumferential strain (r = -0.446 to 0.381, p = 0.000-0.042). LVH patients had a reduced LA emptying fraction compared with NLVH patients and control subjects (p < 0.01). NLVH patients had an impaired LA conduit function and increased contractile function compared with the control group (p < 0.01). LVH patients had increased LA volumes and significantly decreased reservoir, conduit and contractile functions compared with the controls (p < 0.01). LVH patients had increased LA volumes and decreased reservoir and contractile functions compared with NLVH patients (p < 0.01). The clinical utility of LA 4D volume-strain measurement was verified by receiver-operating characteristic curve analysis showing larger net benefits as evaluated with NLVH, LVH and control group comparisons. Interclass correlation coefficients of interobserver and intraobserver assessments in the LV and LA 4D value evaluations were >0.75 and >0.85, respectively.

CONCLUSIONS

LVH patients showed increased LA volumes and decreased LA emptying fractions. LA reservoir, conduit and contractile functions were significantly impaired in LVH patients. Decreased LA conduit function and increased contractile function were revealed in NLVH patients. LA volumetric and functional analyses with 4D volume-strain echocardiography may facilitate the recognition of subtle LA and LV dysfunctions in asymptomatic systemic hypertension patients.

Recent Advances in Imaging of Hypertensive Heart Disease

PURPOSE OF REVIEW

To review recent advances in the imaging of hypertensive heart disease (HHD) with an emphasis on developments in the imaging of diffuse myocardial fibrosis using cardiac magnetic resonance (CMR).

RECENT FINDINGS

HHD results from long-standing hypertension and is characterized by the development of left ventricular hypertrophy and diffuse interstitial fibrosis. Diffuse fibrosis traditionally required endomyocardial biopsy to diagnose, but recent developments using T1 mapping in CMR allow for noninvasive assessment. Studies using T1 mapping have shown an increase in extracellular volume fraction (ECV) in patients with HHD compared to normal controls, suggesting ECV can be used as a noninvasive marker for fibrosis in HHD. In addition to T1 mapping, other recent advances in HHD imaging include improvements in three-dimensional echocardiography, allowing for accurate real-time volumetric measurements, and the use of speckle tracking echocardiography to detect subclinical systolic dysfunction. Measurement of ECV using T1 mapping in CMR can be used as a noninvasive marker of diffuse myocardial fibrosis in HHD. While further studies are needed to validate this approach with larger patient cohorts, ECV can potentially be used to both monitor disease progression and assess therapeutic interventions in HHD.