Malignant hypertension: mechanisms and management

Renal arteriovenous fistula complicated with malignant hypertension: a case report

Renal arteriovenous fistula (RAVF) is a rare vascular disease and is usually presented with severe hypertension. Renin-angiotensin-aldosterone system (RAAS) activation was proposed to play a key role in RAVF-induced hypertension but the data was inconsistent. We reported a case of RAVF presented as malignant hypertension, which was detected by contrast-enhanced ultrasonography and successfully managed by interventional embolization. A 35-year-old male was presented with a headache and blurred vision. His blood pressure was up to 220/110 mmHg, with significantly elevated serum creatinine and proteinuria. Hypertensive target organ impairments were noted. A RAVF was detected by contrast-enhanced renal ultrasonography. He underwent renal artery angiography and renal arteriovenous fistula embolization. RAAS activation was also evaluated by separate renal vein sampling. The patient's blood pressure and target-organ damage improved after RAVF embolization and blood pressure control. This is a rare case of renal arteriovenous fistula with malignant hypertension. Contrast-enhanced ultrasonography can be useful for diagnosis.

Optical coherence tomography measurements in patients with systemic hypertension

AIM

To evaluate the effect of systemic arterial hypertension (SAH) on retinal optical coherence tomography (OCT) parameters and investigate whether a correlation exists between ambulatory blood pressure monitoring (ABPM) and OCT measurements.Material-methods: 115 SAH patients (225 eyes) and 123 healthy control cases (234 eyes) were included. ABPM was performed on 89 of 115 SAH patients. All patients underwent detailed ophthalmologic examination including imaging with OCT. SAH patients were divided into two groups (dippers, non-dippers) according to their nocturnal blood pressure (BP) reduction, and OCT measurements were compared.

RESULTS

Average and superior retinal nerve fiber layer (RNFL) quadrants were significantly thin in hypertensive cases (p:0.002, p < 0.001, respectively). Cup area, cup/disk (c/d) area, and c/d horizontal ratios were wider; the rim area was smaller in hypertensive cases (respectively: p:0.024, p:0.017, p:0.003, p < 0.001). Total macular volume (TMV), the thicknesses in 1-3 and 1-6 mm of the macula were less in hypertensives (p < 0.001). There was no significant difference between dippers and non-dippers in RNFL thickness, macula and optic nerve head (ONH) parameters.

CONCLUSION

There were statistically significant differences between healthy cases and patients with SAH in terms of RNFL, macula thicknesses and ONH parameters.

Characteristics, treatment, and outcome of patients with hypertensive crisis admitted to University of Gondar Specialized Hospital, northwest Ethiopia: A cross-sectional study

Despite major public health initiatives are working in the control of hypertension, hypertensive crisis remains an important clinical problem. This study aimed at examining the characteristics, treatment and outcome of patients with hypertensive crisis admitted to the University of Gondar Specialized Hospital, Ethiopia. A cross-sectional study was conducted on patient medical records (n = 304) between January 01, 2013 and December 31, 2017. Data were analyzed using Statistical Package for Social Sciences version21. A total of 252 patient medical records were included in the analysis. The mean age of the entire patients was 54 ± 17 years. Two hundred and nineteen (86.9%) patients have a documented history of hypertension and on antihypertensive drugs (n = 166, 65.9%). The majority of cases (n = 166, 65.9%) were hypertensive urgencies. In more than one-third of the patients (n = 98, 38.9%), the cause of the illness was attributed to non-compliance to therapy. The most common presenting signs and symptoms at admission were headache (n = 170, 67.5%), dyspnea (n = 36, 14.3%), and vomiting (n = 33, 13.1%). Of 852 tests ordered, the results of one-third (n = 298,34.9%) were abnormal. Nearly two-thirds (n = 336, 59.2%) of prescriptions documented were for hypertensive urgency. Captopril (n = 136, 23.9%) and hydralazine (n = 43, 7.6%) were the most commonly prescribed oral and intravenous drugs respectively. Ten patients died during 55 hours of hospital stay. All hospital mortalities were documented for a hypertensive emergency. The median decrement of diastolic blood pressure among patients with no history of previous admission and hypertensive urgency was significantly higher than those patients with a previous history of admission (P = .005) and hypertensive emergency (P = .010). These findings justify better treatment and follow-up for these patients. Most importantly, to improve compliance with treatment health professionals should provide education to the patients.

The case report of capillary leakage syndrome secondary to malignant hypertension

INTRODUCTION

Capillary leak syndrome (CLS) is characterized by hypoproteinemia, diffused pitting edema, noncardiogenic pulmonary edema, and hypotension. By far, there are no related reports of CLS secondary to malignant hypertension (MHT). A 33-year-old male was admitted to our hospital with the diagnosis of CLS on the background of MHT.

PATIENT CONCERNS

A 33-year-old male was admitted with a 6-day history of worsening dyspnea, chest distress, and diffused pitting edema accompanied by very high blood pressure (200/145 mm Hg).

DIAGNOSES

The tests and examinations showed hypoalbuminemia (26.7 g/L), pulmonary edema, and normal heart function. However, the expected massive proteinuria was absent (1.5 g/24 h). After diuretic and other antihypertensive therapy, the blood pressure reduced gradually; meanwhile, the symptoms of dyspnea and chest distress were improved quickly, and edema in his legs was also reduced. It is surprising that there was no change of pulmonary edema signs on imaging scan, and hypoalbuminemia remained with only mild proteinuria. Thus, our provisional diagnosis of this patient was CLS secondary to MHT.

INTERVENTIONS AND OUTCOMES

We administered intravenous immunoglobulin, sulodexide, and renin-angiotensin system inhibitor to the patient for repairing vascular endothelium and improving the function of vascular endothelium. Before discharge, the patient's edema disappeared and the chest X-ray turned to normal. The level of serum albumin also increased to 35.1 g/L along with the overall improvement. Finally, the renal biopsy revealed malignant hypertensive glomerulosclerosis. All these clinical manifestations were consistent with CLS caused by MHT.

LESSONS

Up to now, there has been no case report of CLS caused by MHT. We should pay more attention to CLS induced by MHT, try to diagnose it as soon as possible, and give prompt treatment to CLS and primary disease.

Hypertensive Crises

Hypertensive crises are a group of medical conditions in which a rapid decrease in blood pressure is necessary to prevent serious complications. Although uncommon in clinical practice, a hypertensive crisis should be recog nized and treated promptly. Any form of hypertension may be associated with hypertensive crisis, the main determinant being the level of blood pressure rather than the cause of hypertension. In certain clinical situa tions the abruptness with which the blood pressure in creases seems to be more important than the absolute level of blood pressure in causing the hypertensive crisis (e.g., toxemia of pregnancy in women and acute onset of hypertension in children with acute glomerulo nephritis). In other clinical situations the absolute level of blood pressure does not affect the seriousness of hy pertension so much as coexisting complications that may make even moderate hypertension dangerous (e.g., acute aortic dissection and acute left ventricular fail ure ).

Hypertensive crisis in children

Hypertensive crisis is rare in children and is usually secondary to an underlying disease. There is strong evidence that the renin-angiotensin system plays an important role in the genesis of hypertensive crisis. An important principle in the management of children with hypertensive crisis is to determine if severe hypertension is chronic, acute, or acute-on-chronic. When it is associated with signs of end-organ damage such as encephalopathy, congestive cardiac failure or renal failure, there is an emergent need to lower blood pressures to 25-30% of the original value and then accomplish a gradual reduction in blood pressure. Precipitous drops in blood pressure can result in impairment of perfusion of vital organs. Medications commonly used to treat hypertensive crisis in children are nicardipine, labetalol and sodium nitroprusside. In this review, we discuss the pathophysiology, differential diagnosis and recent developments in management of hypertensive crisis in children.

Angiotensin-converting enzyme i/d polymorphism in patients with malignant hypertension

The angiotensin-converting enzyme (ACE) gene has been implicated in the manifestation of the phenotype of malignant hypertension (MH). In 1990 the ACE gene polymorphism characterized by the insertion or deletion of a 287-base pair fragment in the 17q23 chromosome was identified. The DD genotype is associated with increased tissue and circulating ACE levels and elevated angiotensin II. ACE polymorphism was studied in 48 patients with MH, 25 patients with non-MH, and a control group of 78 normotensive individuals by real-time polymerase chain reaction using the LightCycler system (Roche Diagnostics Corporation, Indianapolis, IN). The DD genotype was found statistically more frequently in MH patients than controls (p=0.028; odds ratio, 2.5; confidence interval, 1.1-5.5). Presence of the DD genotype of the ACE gene is more frequent in MH patients than in controls, indicating that this genotype could be a significant risk factor and a predictor for the development of MH.

Angiotensin-converting enzyme gene I/D polymorphism in malignant hypertension

BACKGROUND

The mechanism of the rapid transition of a stable benign hypertensive disease to a severe and devastating malignant hypertension is not fully understood. However, the renin angiotensin system, which is highly activated in malignant hypertension, is established as an important pathogenetic factor in different cardiovascular and renal diseases. Over the last decade, a polymorphism in genes regulating this system has been found. This includes the 287 bp sequence deletion (D)/insertion (I) polymorphism in the angiotensin-converting enzyme (ACE) gene and the methionine (M) to threonine (T) point mutation polymorphism in the angiotensinogen (AGT) gene. These gene polymorphisms have been associated with various cardiovascular and renal diseases and the aim of this study was to investigate whether they were linked to malignant hypertension.

METHODS

Forty-two patients with malignant hypertension (mean age 55 years), 42 patients with non-malignant hypertension (mean age 57 years) and 85 normotensive control subjects (mean age 42 years) were investigated with respect to ACE I/D and AGT M/T genotypes. DNA was prepared by standard methods from isolated white blood cells and analysed by the PCR technique. The PCR reaction used in the detection of the ACE I/D polymorphism was optimized for an equal amplification of the I and D alleles.

RESULTS

The frequency of the DD genotype was significantly increased in patients with malignant hypertension (43%) compared with patients with non-malignant hypertension (14%) and normotensive control subjects (18%) (p <0.01) for both. The frequency distribution of AGT M/T genotype did not differ between patients with malignant and non-malignant hypertension.

CONCLUSION

The DD genotype of the ACE gene occurred more than twice as often in malignant hypertension than in non-malignant hypertension and indicates that ACE gene polymorphism is a significant risk factor for initiation of malignant hypertension.

Asymptomatic hypertension in the ED

A retrospective study in an urban, municipal, teaching hospital emergency department (ED) was conducted to evaluate (1) the frequency of asymptomatic hypertension in the ED, (2) the initial assessment and patterns of treatment by physicians, and (3) the changes in blood pressure (BP) in these patients. Patients with systolic BP > or = 180 mm Hg or diastolic BP > or = 110 mm Hg were included. Patients with cardiovascular, renal, or central nervous system dysfunction were excluded. Of the 11,531 charts reviewed, 269 (2.3%) met inclusion criteria. Of the 269 patients, 56 patients (20.8%) received antihypertensive treatment in the ED. The treatment group had a higher systolic BP (P < .001), diastolic BP (P < .001), and mean arterial blood pressure (MAP) (P < .001) than the nontreatment group. Fundoscopy was also performed more frequently in the treatment group (30.2% v 8.9%, P < .001). MAP decreased for both groups in the ED, but was higher in the treatment group (-20+/-21 v -11+/-21 mm Hg, P=.02). Despite the lack of support in the literature for the emergency treatment of asymptomatic hypertension in the ED, the individual physician's decision for treatment correlated with the degree of hypertension. Significantly elevated BP readings in the ED tended to decrease over time independent of any antihypertensive treatment, although the decrease was larger in the treated patients.

Erythrocyte sodium transport in malignant hypertension

Twenty-three patients with treated malignant hypertension (MH), 23 patients with treated non-malignant hypertension (NMH) and 46 normotensive control subjects were investigated with regard to intraerythrocyte sodium (Na) and potassium (K) levels, as well as transmembrane fluxes of sodium (Na-influx and Na-efflux rate constant). Intraerythrocyte Na and K concentrations were determined by flame photometry. The Na-influx and Na-efflux rate constant were calculated from uptake values for 22Na in vitro. In NMH the Na-influx and Na-efflux rate constant were significantly higher while intraerythrocyte Na and K levels did not differ from the controls. Patients with MH tended to have an elevated intraerythrocyte Na concentration, but an unchanged Na-influx and Na-efflux rate constant relative to controls. The increased rate of erythrocyte membrane transport of Na in treated NMH could be due to a stimulatory effect of antihypertensive treatment on cellular Na transport. Patients with treated MH do not show this effect, and in addition, tend to have an elevated intraerythrocyte Na concentration, which is compatible with the existence of a more pronounced abnormality of cellular ion transport in MH.

Hypertensive emergency: case criteria, sociodemographic profile, and previous care of 100 cases

To study the frequency, cost, sociodemographic profile, and previous care correlates of hospital admissions for hypertensive emergency, we used specific case criteria to identify a series of 100 cases at Presbyterian Hospital in New York City. Approximately 58 cases were admitted per year. Mean length of hospital stay was 11.8 days, 75 per cent of patients received intensive care, and estimated annual hospital charges were $438,828 (1986 dollars). Cases had severe hypertension on admission (mean systolic blood pressure, 229.8 mmHg; mean diastolic blood pressure, 143 mmHg). Two-thirds had clinical evidence of acute arteriolitis. Cases were predominantly young, male, Black or Hispanic, and of lower socioeconomic status. At least 93 per cent of cases were previously diagnosed, and at least 83 per cent were aware of their diagnosis of hypertension. Improved management of chronic hypertension rather than more intensive screening may be a useful strategy to reduce the incidence of hypertensive emergency.

Hypertensive crisis

Although rare, hypertensive crises may rapidly lead to irreversible organ damage or death. Their prompt recognition, based primarily on physical signs and symptoms, is essential. Appropriately aggressive therapy, and evaluation of precipitating and exacerbating conditions, will often result in a satisfactory outcome.

Lithium-induced uraemia in rats: survival and renal function and morphology after one year

Chronic renal failure was induced in Wistar rats by administration of a LiCl-containing (40 mmol/kg) diet from birth until an age of 55-65 weeks. The 55 weeks mortality was 51% in Li-uraemic rats versus 6% in control rats. In surviving rats the mean plasma Li levels were 0.6-0.7 mmol/l after 16 weeks and 1.0-1.1 mmol/l after 48 weeks. The mean plasma urea level was 14 mmol/l after 16 weeks and 22 mmol/l after 48 weeks of treatment compared with 8 mmol/l in the controls rats. In 55 weeks old Li-uraemic rats inulin clearance was reduced by 62% and Li clearance by 39%. Thus, fractional Li excretion was increased (from 20 to 34%) in rats with chronic Li-uraemia. Li-uraemic rats also had polyuria and failed to concentrate their urine in response to exogenous vasopressin. Systolic and mean arterial blood pressures were not significantly changed in rats with Li-uraemia. Morphological examinations of the kidneys showed large cortical cysts formed by dilated distal tubules and collecting ducts and widespread interstitial fibrosis. Proximal tubular mass was reduced by 50% and glomerular volume was also significantly reduced. The results indicate that in rats with Li-induced uraemia renal function and morphology deteriorate during Li-exposure up to an age of one year, associated with increased mortality.

Pathology of small blood vessel disease in hypertension

A pathogenic role for arterioles in hypertension has been postulated for many decades. Renal arteriolonecrosis, myointimal hyperplasia, and hyaline arteriolosclerosis are anatomic correlates of hypertension. The pathogenesis of these lesions is discussed as is contribution of these lesions to the perpetuation of hypertension. The importance of the extracellular matrix in the initiation and development of hyaline arteriolosclerosis is presented and correlated with the hemodynamic and pathophysiologic consequences of increased transmural pressure. The possibility of aiming therapy at arresting or ameliorating arteriolar disease is presented.

Renal function as an indicator of prognosis in malignant essential hypertension

Renal function was evaluated in a group of 24 patients (21 men and 3 women, mean age 47 years) who had survived the malignant phase of hypertension during the period of 1969-1979. Five had grade III retinopathy (haemorrhages and exudates) and 19 had grade IV changes (papilloedema, FH IV) at diagnosis. Highest recorded blood pressure was 248 +/- 4/152 +/- 3 mmHg (mean +/- S.E.M.). Renal function rapidly deteriorated in 7 cases with progression to terminal uraemia. All patients in this group had a marked elevation in serum creatinine at diagnosis (448 +/- 105 mumol/l) and inadequate blood pressure control. Two of these 7 patients died and 5 underwent renal transplantation. The other 17 patients initially had serum creatinine less than or equal to 250 mumol/l (169 +/- 19 mumol/l-glomerular filtration rate (GFR) 51 +/- 7 ml/min). All except one were reinvestigated after a mean time of 6 years (range 6 months-11 years) with evaluation of blood pressure and determination of GFR by 51Cr-EDTA clearance. At follow-up their blood pressure was fairly well controlled (153 +/- 3/99 +/- 2 mmHg). Their GFR was 62 +/- 6 ml/min. Of the 11 patients in whom two GFR determinations were available (one initially and one at follow-up), six patients showed a marked increase in GFR while 5 patients showed only slight or no improvement in spite of fairly good blood pressure control. In malignant hypertension adequate antihypertensive treatment can lead to a pronounced improvement in GFR unless renal function has deteriorated gravely.

Renal pathology in hypertension and the effects of treatment

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