Resistant Hypertension: A Clinical Perspective

Etiology and Management of Treatment-Resistant Hypertension in African American Adults ≥18 Years: A Literature Review

Treatment-resistant hypertension (TRH) is defined as blood pressure levels that remain above the therapeutic goal despite concurrent use of three or more antihypertensive medications taken at maximally tolerated doses, one of which should be a diuretic. Additionally, individuals on four or more antihypertensive agents regardless of blood pressure are also considered to have TRH. Amongst people diagnosed with TRH, African American adults face a huge management gap, resulting in increased cardiovascular disease risk. The primary objective of this review was to identify the commonly encountered etiologies and extensively discuss the current management strategies of TRH with a particular focus on African Americans. Relevant studies were identified by analyzing scientific databases and journals such as PubMed, Cochrane, MEDLINE, Cureus, and American Heart Association (AHA). The studies identified and examined common causes of TRH, describing their pathophysiology and highlighting different treatment options for the respective etiologies. The most prevalent etiologies of TRH amongst African Americans were chronic kidney disease (CKD), renal artery stenosis (RAS), fibromuscular dysplasia, obstructive sleep apnea (OSA), endocrine causes (Conn syndrome, Cushing syndrome, etc.), sympathetic nervous system overactivity, lifestyle factors, inaccurate blood pressure measurement, and inappropriate treatment. Of the etiologies reviewed, OSA, lifestyle factors, and CKD exhibited a striking prevalence among the subpopulation studied. Unfortunately, there was a paucity of articles addressing this topic amongst African Americans, and therefore there was not a substantial appreciation of the prevalence of some of the identified etiologies in the population of interest. Thorough diagnostic testing for associated or underlying conditions provides a basis for successful management. This review brought to the fore the need for doctors and patients to collaborate in order to improve TRH management and help patients lead healthier lives.

Hypertension and COVID-19: Updates from the era of vaccines and variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for coronavirus disease 2019 (COVID-19) has been a major cause of morbidity and mortality globally. Older age, and the presence of certain components of metabolic syndrome, including hypertension have been associated with increased risk for severe disease and death in COVID-19 patients. The role of antihypertensive agents in the pathogenesis of COVID-19 has been extensively studied since the onset of the pandemic. This review discusses the potential pathophysiologic interactions between hypertension and COVID-19 and provides an up-to-date information on the implications of newly emerging SARS-CoV-2 variants, and vaccines on patients with hypertension.

CIHH protects the heart against left ventricular remodelling and myocardial fibrosis by balancing the renin-angiotensin system in SHR

AIM

The aim of our study was to clarify the cardioprotection of chronic intermittent hypobaric hypoxia (CIHH) and the underlying mechanism in spontaneously hypertensive rats (SHR).

MAIN METHODS

Adult male rats were divided into normal blood pressure Wistar-Kyoto rats (WKY) control (WKY-CON), WKY rats with CIHH treatment (WKY-CIHH), SHR control (SHR-CON) and SHR with CIHH treatment (SHR-CIHH) groups. SHR-CIHH and WKY-CIHH rats were subjected to hypobaric hypoxia simulating 4000-m altitude for 35 days, 5 h per day. Arterial blood pressure and cardiac function parameters, including ejection fraction, fractional shortening and left ventricular (LV) wall thickness, were evaluated. Cardiac pathomorphology and myocardial fibrosis were determined. The expression of angiotensin-converting enzyme (ACE), ACE2, Ang II, Ang1-7, AT1 receptor, Mas receptor, IL-6, TNF-α，IL-10, SOD and MDA were assayed in myocardium.

KEY FINDINGS

CIHH significantly decreased arterial blood pressure, alleviated LV hypertrophy, and improved cardiovascular function in SHR (P < 0.05-0.01). Also, CIHH protected SHR heart against morphological changes and fibrosis. In addition, CIHH significantly down-regulated the ACE/Ang II/AT1 receptor axis and up-regulated the ACE2/Ang1-7/Mas axis of renin-angiotensin system (RAS) in SHR (P < 0.05-0.01). CIHH significantly reduced IL-6, TNF-α, and MDA levels, but increased IL-10 and SOD in SHR myocardium (P < 0.05-0.01).

SIGNIFICANCE

The CIHH treatment protected the heart of SHR against LV remodelling and myocardial fibrosis, which might be carried out through a balance in the ACE/Ang II/AT1 axis and the ACE2/Ang1-7/Mas axis of the RAS to reduce inflammation, and inhibit oxidative stress.

Control of blood pressure levels in patients with premature coronary artery disease: Results from the Genetics of Atherosclerotic Disease study

High blood pressure (BP) is the major cardiovascular-risk factor for coronary artery disease (CAD), principally in young patients who have an important and increasing socioeconomic burden. Despite the Seventh Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-7), recommended BP target <140/90 mm Hg for patients with stable CAD, in 2017 the American College of Cardiology and the American Heart Association (ACC/AHA) updated BP target to <130/80 mm Hg. We aimed to analyze the prevalence of BP control in patients with premature CAD using both criteria. In addition, antihypertensive therapy, lifestyle, clinical, and sociodemographic characteristics of the patients were evaluated in order to identify factors associated with the achievement of BP targets. The present study included 1206 patients with CAD diagnosed before 55 and 65 years old in men and women, respectively. Sociodemographic, clinical, and biochemical data were collected. The results indicate that 85.6% and 77.5% of subjects with premature CAD achieved JNC-7 non-strict and ACC/AHA strict BP target, respectively. Consistently, number of antihypertensive drugs and hypertension duration >10 years were inversely associated with BP targets, whereas total physical activity and smoking were directly associated with BP targets, regardless of BP criteria. Considering that age, gender, and hypertension duration are non-modifiable cardiovascular-risk factors, our results highlight the need for more effective strategies focused on increase physical activity and smoking cessation in young patients with CAD. These healthier lifestyles changes should favor the BP target achievement and reduce the socioeconomic and clinical burden of premature CAD.