Malignant hypertension: does this still exist?

Evaluation and management of hypertensive emergency

Hypertensive emergencies cause substantial morbidity and mortality, particularly when acute organ injury is present. Careful and effective strategies to reduce blood pressure and diminish the effects of pressure-mediated injury are essential. While the selection of specific antihypertensive medications varies little across different forms of hypertensive emergencies, the intensity of blood pressure reduction to the target pressure differs substantially. Treatment hinges on balancing the positive effects of lowering blood pressure with the potential for negative effects of organ hypoperfusion in patients with altered autoregulatory mechanisms. When patients do not have acute organ injury in addition to severe hypertension, they benefit from a conservative, outpatient approach to blood pressure management. In all cases, long term control of blood pressure is paramount to prevent recurrent hypertensive emergencies and improve overall prognosis. This review discusses the current evidence and guidelines on the evaluation and management of hypertensive emergency.

Serum Elabela expression is decreased in hypertensive patients and could be associated with the progression of hypertensive renal damage

BACKGROUND

Elabela, a recently discovered hormonal peptide containing 32 amino acids, is a ligand for the apelin receptor. It can lower blood pressure and attenuate renal fibrosis. However, the clinicopathological relationship between Elabela level and renal damage caused by benign hypertension (BHT) and malignant hypertension (MHT) has not been elucidated. Therefore, we investigated the clinicopathological correlation between serum Elabela level and renal damage caused by BHT and MHT.

METHODS

The participants comprised 50 patients and 25 age-matched healthy adults. The 50 patients were separated into two groups: MHT (n = 25) and BHT groups (n = 25). We analyzed their medical histories, demographics, and clinical examinations, including physical and laboratory tests.

RESULTS

The results showed that serum Elabela level decreased gradually with a continuous increase in blood pressure from the healthy control group, BHT, to MHT. Moreover, Elabela levels negatively correlated with BMI (R =  - 0.27, P = 0.02), SBP (r =  - 0.64, P < 0.01), DBP (r =  - 0.58, P < 0.01), uric acid (r =  - 0.39, P < 0.01), bun (r =  - 0.53, P < 0.01), and Scr (r =  - 0.53 P < 0.01) but positively correlated with eGFR (r = 0.54, P < 0.01). Stepwise multivariate linear regression analysis showed that SBP was the variable most related to Elabela (t =  - 5.592, P < 0.01).

CONCLUSIONS

Serum Elabela levels decreased in patients with hypertension, especially malignant hypertension, and has the potential to be a marker of hypertension-related kidney damage.

Management of hypertensive crisis: British and Irish Hypertension Society Position document

Patients with hypertensive emergencies, malignant hypertension and acute severe hypertension are managed heterogeneously in clinical practice. Initiating anti-hypertensive therapy and setting BP goal in acute settings requires important considerations which differ slightly across various diagnoses and clinical contexts. This position paper by British and Irish Hypertension Society, aims to provide clinicians a framework for diagnosing, evaluating, and managing patients with hypertensive crisis, based on the critical appraisal of available evidence and expert opinion.

No benefit of HIF prolyl hydroxylase inhibition for hypertensive renal damage in renovascular hypertensive rats

Introduction: We previously reported that malignant hypertension is associated with impaired capillary density of target organs. Here, we tested the hypothesis that stabilization of hypoxia-inducible factor (HIF) in a modified "preconditioning" approach prevents the development of malignant hypertension. To stabilize HIF, we employed pharmacological inhibition of HIF prolyl hydroxylases (PHD), that profoundly affect HIF metabolism. Methods: Two-kidney, one-clip renovascular hypertension (2K1C) was induced in rats; controls were sham operated. 2K1C rats received either intermittent injections of the PHD inhibitor ICA (2-(1-chloro-4-hydroxyisoquinoline-3-carboxamido) acetate) or placebo. Thirty-five days after clipping, the frequency of malignant hypertension was assessed (based on weight loss and the occurrence of characteristic vascular lesions). In addition, kidney injury was compared between all ICA treated versus all placebo treated 2K1C, regardless of the occurrence of malignant hypertension. HIF stabilization was evaluated by immunohistochemistry, and HIF target gene expression by RT-PCR. Results: Blood pressure was elevated to the same degree in ICA- and placebo-treated 2K1C compared to control rats. ICA treatment did not affect the frequency of malignant hypertension or the extent of kidney tissue fibrosis, inflammation, or capillary density. There was a trend towards higher mortality and worse kidney function in ICA-treated 2K1C rats. ICA increased the number of HIF-1α-positive renal tubular cell nuclei and induced several HIF-1 target genes. In contrast, expression of HIF-2α protein as well as HIF-2 target genes were markedly enhanced by 2K1C hypertension, irrespective of ICA treatment. Discussion: We conclude that intermittent PHD inhibition did not ameliorate severe renovascular hypertension in rats. We speculate that the unexpected strong renal accumulation of HIF-2α in renovascular hypertension, which could not be further augmented by ICA, may contribute to the lack of a benefit from PHD inhibition.

Clinical characteristics and outcomes of a patient population with atypical hemolytic uremic syndrome and malignant hypertension: analysis from the Global aHUS registry

INTRODUCTION

Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy (TMA) often caused by alternative complement dysregulation. Patients with aHUS can present with malignant hypertension (MHT), which may also cause TMA.

METHODS

This analysis of the Global aHUS Registry (NCT01522183) assessed demographics and clinical characteristics in eculizumab-treated and not-treated patients with aHUS, with (n = 71) and without (n = 1026) malignant hypertension, to further elucidate the potential relationship between aHUS and malignant hypertension.

RESULTS

While demographics were similar, patients with aHUS + malignant hypertension had an increased need for renal replacement therapy, including kidney transplantation (47% vs 32%), and more pathogenic variants/anti-complement factor H antibodies (56% vs 37%) than those without malignant hypertension. Not-treated patients with malignant hypertension had the highest incidence of variants/antibodies (65%) and a greater need for kidney transplantation than treated patients with malignant hypertension (65% vs none). In a multivariate analysis, the risk of end-stage kidney disease or death was similar between not-treated patients irrespective of malignant hypertension and was significantly reduced in treated vs not-treated patients with aHUS + malignant hypertension (adjusted HR (95% CI), 0.11 [0.01-0.87], P = 0.036).

CONCLUSIONS

These results confirm the high severity and poor prognosis of untreated aHUS and suggest that eculizumab is effective in patients with aHUS ± malignant hypertension. Furthermore, these data highlight the importance of accurate, timely diagnosis and treatment in these populations and support consideration of aHUS in patients with malignant hypertension and TMA.

TRIAL REGISTRATION DETAILS

Atypical Hemolytic-Uremic Syndrome (aHUS) Registry. Registry number: NCT01522183 (first listed 31st January, 2012; start date 30th April, 2012).

Case report: Area of focus in a case of malignant hypertension

Malignant hypertension (MH) is characterized by severe hypertension (usually grade 3) associated with fundoscopic changes (flame hemorrhages and/or papilledema), microangiopathy and disseminated intravascular coagulation. In addition encephalopathy, acute heart failure and acute deterioration in renal function may be present. The term "malignant" reflects the very poor prognosis for this condition if untreated. When severe hypertension is associated with hypertension-mediated organ damage (HMOD) a life-threatening situation that requires immediate but careful intervention occurs (hypertensive emergency). In the last few years an increase in the number of patients with malignant hypertension has been observed, especially among those patients with black ethnicity. Limited access to treatment and the poor adherence to anti-hypertensive therapy may contribute to the development of hypertensive emergencies. It is considered appropriate to study patients in order to rule out thrombotic thrombocytopenic purpura and hemolytic uremic syndrome. In fact, the microvascular damage caused by malignant hypertension can favor intravascular hemolysis like Thrombotic Microangiopathies (TMs). TMs may present in three different clinical conditions: typical hemolytic uremic syndrome (HUS), atypical hemolytic uremic syndrome (aHUS) and thrombotic thrombocytopenic purpura (TTP). TMs can arise in the context of other pathological processes, including malignant hypertension.

A Case of Takayasu Arteritis with Thrombotic Microangiopathy Secondary to Malignant Hypertension Due to Bilateral Renal Artery Stenosis

A 20 year old woman presented with right arm pain. Pulses of right upper extremity were weak, acute phase reactants were elevated and MR angiography demonstrated total occlusion of subclavian artery and right axillary artery with collaterals. The diagnosis was Takayasu arteritis and she was treated with prednisolone, azathioprine and acetylsalicylic acid. During follow up, azathioprine was switched to methotrexate. Three years later, patient presented with elevated blood pressure. CT angiography demonstrated reduced calibration of the aorta and almost total occlusion of the lumen of proximal parts of left and right renal arteries. C-reactive protein was elevated. Steroid dose was increased, methotrexate was discontinued and IV tocilizumab and antihypertensive medications were initiated. One month later, she presented to emergency department with elevated blood pressure and blurred vision in the left eye. Fundoscopic examination revealed bilateral grade 3 hypertensive retinopathy and serous detachment of retina in the left eye. Laboratory results revealed normal CRP, elevated creatinine, elevated lactate dehydrogenase, thrombocytopenia, low hemoglobin and low haptoglobin. Peripheral blood smear revealed 2–3 schistocytes in every field. She was admitted to rheumatology department with the diagnosis of thrombotic microangiopathy secondary to malignant hypertension. IV tocilizumab was administered, and methylprednisolone was maintained at a dose of 20 mg/day. Despite treatment with maximum dose of six antihypertensive medications, her blood pressure was not controlled adequately and she became hypervolemic. After undergoing ultrafiltration, balloon dilation was performed in the left renal artery, and a stent was placed there. After stent placement, creatinine and platelet count normalized, hemoglobin increased and hypertension was controlled. In this case, malignant hypertension which was triggered by bilateral renal artery stenosis due to Takayasu arteritis had caused acute kidney injury and advanced stage hypertensive retinopathy. In addition, unlike other Takayasu arteritis cases with malignant hypertension, thrombotic microangiopathy was also detected.

Hypertensive eye disease

Hypertensive eye disease includes a spectrum of pathological changes, the most well known being hypertensive retinopathy. Other commonly involved parts of the eye in hypertension include the choroid and optic nerve, sometimes referred to as hypertensive choroidopathy and hypertensive optic neuropathy. Together, hypertensive eye disease develops in response to acute and/or chronic elevation of blood pressure. Major advances in research over the past three decades have greatly enhanced our understanding of the epidemiology, systemic associations and clinical implications of hypertensive eye disease, particularly hypertensive retinopathy. Traditionally diagnosed via a clinical funduscopic examination, but increasingly documented on digital retinal fundus photographs, hypertensive retinopathy has long been considered a marker of systemic target organ damage (for example, kidney disease) elsewhere in the body. Epidemiological studies indicate that hypertensive retinopathy signs are commonly seen in the general adult population, are associated with subclinical measures of vascular disease and predict risk of incident clinical cardiovascular events. New technologies, including development of non-invasive optical coherence tomography angiography, artificial intelligence and mobile ocular imaging instruments, have allowed further assessment and understanding of the ocular manifestations of hypertension and increase the potential that ocular imaging could be used for hypertension management and cardiovascular risk stratification.

[Malignant hypertension and pheochromocytoma: a case report]

Malignant arterial hypertension is defined by extremely high levels of pressure associated with organ damage. It is a cause of hypertensive emergency and is defined by the coexistence of high blood pressure and bilateral retinal haemorrhage or exudates (grade III hypertensive retinopathy), with or without papilloedema (grade IV hypertensive retinopathy) currently associated with organ damage such as renal or cardiac failure. Around 1% of malignant arterial hypertension is secondary to endocrinological causes, including the most common: pheochromocytoma, which is classically characterized by the triad: headache, sweating and palpitations. However, there is no single clinical finding that is of significant value in its diagnosis. We now present the case of a 23-year-old patient with a hypertensive emergency, an adrenal mass associated with grade IV hypertensive retinopathy.

Accuracy of a Symptom-Based Approach to Identify Hypertensive Emergencies in the Emergency Department

BACKGROUND

A hierarchical symptoms-based diagnostic strategy relying on the presence of five main symptoms (chest pain, acute dyspnea, neurological symptoms, headache, visual impairment) was recently proposed to diagnose patients with hypertensive emergency. However, poor scientific evidence is available about the role of symptoms in both diagnosis and management of acute hypertensive disorders.

METHODS

Data from 718 patients presenting to the emergency department of the "Città della Salute e della Scienza" Hospital of Turin with systolic blood pressure > 180 and/or diastolic blood pressure > 110 mm/Hg were retrospectively analyzed. The accuracy of the typical symptoms for identification of hypertensive emergencies was assessed.

RESULTS

A total of 79 (11%) out of 718 patients were diagnosed with hypertensive emergencies (51% had cardiovascular and 49% neurovascular acute organ damage). Patients with hypertensive emergencies were older and with higher prevalence of coronary artery disease and chronic heart failure than patients with uncontrolled hypertension. Typical symptoms could discriminate true hypertensive emergency from uncontrolled hypertension with 64% accuracy, 94% sensitivity, and 60% specificity.

CONCLUSION

Typical symptoms might be used as a simple screening test (99% negative predictive value) in the emergency department to select for further evaluations of patients with suspected hypertensive emergencies among those with acute hypertensive disorders.