Anti-hypertensive drugs and left ventricular hypertrophy: a clinical update

Automated Classification of Left Ventricular Hypertrophy on Cardiac MRI

Left ventricular hypertrophy is an independent predictor of coronary artery disease, stroke, and heart failure. Our aim was to detect LVH cardiac magnetic resonance (CMR) scans with automatic methods. We developed an ensemble model based on a three-dimensional version of ResNet. The input of the network included short-axis and long-axis images. We also introduced a standardization methodology to unify the input images for noise reduction. The output of the network is the decision whether the patient has hypertrophy or not. We included 428 patients (mean age: 49 ± 18 years, 262 males) with LVH (346 hypertrophic cardiomyopathy, 45 cardiac amyloidosis, 11 Anderson–Fabry disease, 16 endomyocardial fibrosis, 10 aortic stenosis). Our control group consisted of 234 healthy subjects (mean age: 35 ± 15 years; 126 males) without any known cardiovascular diseases. The developed machine-learning-based model achieved a 92% F1-score and 97% recall on the hold-out dataset, which is comparable to the medical experts. Experiments showed that the standardization method was able to significantly boost the performance of the algorithm. The algorithm could improve the diagnostic accuracy, and it could open a new door to AI applications in CMR.

Electrocardiography for the detection of left ventricular hypertrophy in an elderly population with long-standing hypertension in primary care: a secondary analysis of the CHELLO cohort study

OBJECTIVES

To investigate: (1) the prevalence of left ventricular hypertrophy (LVH) in elderly primary care patients with long-standing asymptomatic hypertension, and (2) the diagnostic value of ECG as a screening tool in the detection of LVH compared with echocardiography in this specific patient population.

DESIGN AND SETTINGS

A cross-sectional study in five general practices in the south-east of the Netherlands.

PARTICIPANTS

Patients with primary care-managed hypertension, aged between 60 and 85 years, without known heart failure.

PRIMARY AND SECONDARY OUTCOME MEASURES

Between June 2010 and January 2013, the patients underwent structured interviews, blood pressure assessment, laboratory testing, ECGs and echocardiograms. The primary outcome was to investigate the ability of ECG to detect LVH, compared with echocardiography as a reference test (gold standard).

RESULTS

Four hundred and twenty-two patients (44% male; ages 70±7 years) who underwent ECG and echocardiographic assessment to determine LVH were included. The median duration of hypertension was 10 (4-15) years. The overall prevalence of LVH was 44%, which increased with age (p<0.001); up to 60% of patients were ≥75 years. ECG intimated LVH in 47 patients (11%) but in only 26 of those (55%) was LVH confirmed by echocardiography. The sensitivity of ECG for detecting LVH was poor (14%).

CONCLUSIONS

Asymptomatic primary care patients with long-standing hypertension have a high prevalence of previously undetected LVH, which increases with age. ECG is inadequate for detecting LVH in these patients. Early detection of LVH could potentially create more awareness for the optimal regulation of hypertension and compliance to therapy. Therefore, echocardiography should be considered a screening device for the detection of LVH in this population.

Prediction of stroke with electrocardiographic left ventricular hypertrophy in hypertensive patients: A meta-analysis

BACKGROUND

Electrocardiographic left ventricular hypertrophy (LVH) has been used to predict adverse prognosis in hypertensive patients. This meta-analysis aimed to investigate the association between LVH using the different electrocardiographic criteria in patients with hypertension.

METHODS

A comprehensive literature search was performed PubMed and Embase databases up to September 1, 2019. Observational studies evaluating the association between electrocardiographic LVH (Cornell voltage, Cornell product or Sokolow-Lyon voltage) at baseline and risk of stroke among hypertensive patients were selected. The risk ratio (RR) with 95% confidence interval (CI) was pooled for patients with electrocardiographic LVH versus without LVH.

RESULTS

Seven studies enrolling 58,098 hypertensive patients were included. When compared those with or without LVH patients showed that the pooled RR of stroke was 1.63 (95% CI 1.38-1.93) for Cornell voltage criteria, 1.41 (95% CI 1.07-1.86) for Cornell product criteria, and 1.42 (95% CI 1.20-1.69) for Sokolow-Lyon voltage criteria, respectively. However, the predictive significance of Cornell product criteria was not reliable in the sensitivity analysis.

CONCLUSIONS

Baseline electrocardiographic LVH detecting by Sokolow-Lyon or Cornell voltage criteria can predict the development of stroke in hypertensive patients. Use of electrocardiographic LVH can improve stroke risk stratification in hypertensive patients.

Hypertension strengthens δ-ALA-D activity inhibition and increases it reactivation index in type 2 diabetic patients

AIMS

To assess the effect of hypertension on δ-aminolevulinate dehydratase (δ-ALA-D) activity of type 2 diabetic patients (T2DM).

METHODS

δ-ALA-D activity and reactivation index, as well as markers of oxidative stress, biochemical and anthropometrics parameters were determined in T2DM (n=23), type 2 diabetic patients with hypertension (T2DM/HT) (n=30) and controls (n=30).

RESULTS

T2DM/HT presented a greater inhibition of δ-ALA-D activity, a higher reactivation index (p<0.05) and a greater depletion of plasma protein thiol groups (P-SH) when compared to T2DM. Moreover, δ-ALA-D activity was positively associated with SH groups and negatively associated with serum protein carbonyl (PC) while its reactivation index was negatively associated with SH groups and positively associated with PC.

CONCLUSIONS

These results point out that there is a possible interference of hypertension on the mechanism of the δ-ALA-D activity suggesting that this condition aggravated the oxidative stress of diabetes mellitus.

Simvastatin modulates remodeling of Kv4.3 expression in rat hypertrophied cardiomyocytes

Objectives: Hypertrophy has been shown to be associated with arrhythmias which can be caused by abnormal remodeling of the Kv4-family of transient potassium channels. Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (statins) have recently been shown to exert pleiotropic protective effects in cardiovascular diseases, including anti-arrhythmias. It is hypothesized that remodeling of Kv4.3 occurs in rat hypertrophied cardiomyocytes and is regulated by simvastatin.

Methods: Male Sprague-Dawley rats and neonatal rat ventricular myocytes (NRVMs) underwent abdominal aortic banding (AAB) for 7 weeks and angiotensin II (AngII) treatment, respectively, to induce cardiac hypertrophy. Kv4.3 expression by NRVMs and myocardium (subepicardial and subendocardial) in the left ventricle was measured. The transient outward potassium current (I_to) of NRVMs was recorded using a whole-cell patch-clamp method.

Results: Expression of the Kv4.3 transcript and protein was significantly reduced in myocardium (subepicardial and subendocardial) in the left ventricle and in NRVMs. Simvastatin partially prevented the reduction of Kv4.3 expression in NRVMs and subepicardial myocardium but not in the subendocardial myocardium. Hypertrophied NRVMs exhibited a significant reduction in the I_to current and this effect was partially reversed by simvastatin.

Conclusions: Simvastatin alleviated the reduction of Kv4.3 expression, I_to currents in hypertrophied NRVMs and alleviated the reduced Kv4.3 expression in subepicardial myocardium from the hypertrophied left ventricle. It can be speculated that among the pleiotropic effects of simvastatin, the anti-arrhythmia effect is partly mediated by its effect on Kv4.3.