Impact of malignant arterial hypertension on the heart

Malignant Hypertension:A Systemic Cardiovascular Disease: JACC Review Topic of the Week

Malignant hypertension (MHT) is a hypertensive emergency with excessive blood pressure (BP) elevation and accelerated disease progression. MHT is characterized by acute microvascular damage and autoregulation failure affecting the retina, brain, heart, kidney, and vascular tree. BP must be lowered within hours to mitigate patient risk. Both absolute BP levels and the pace of BP rise determine risk of target-organ damage. Nonadherence to the antihypertensive regimen remains the most common cause for MHT, although antiangiogenic and immunosuppressant therapy can also trigger hypertensive emergencies. Depending on the clinical presentation, parenteral or oral therapy can be used to initiate BP lowering. Evidence-based outcome data are spotty or lacking in MHT. With effective treatment, the prognosis for MHT has improved; however, patients remain at high risk of adverse cardiovascular and kidney outcomes. In this review, we summarize current viewpoints on the epidemiology, pathogenesis, and management of MHT; highlight research gaps; and propose strategies to improve outcomes.

Persistently elevated sFlt-1 and recovery of reduced ADAMTS13 activity in malignant hypertension

BACKGROUND AND OBJECTIVES

Malignant hypertension (MHT) characterized by acute hypertension with retinopathy or multiorgan damage, is a severe form of hypertensive emergency and associated with target organ involvement and poor kidney outcome. However, the underlying mechanisms are unclear.

METHODS

Eighty-four patients with acute severe hypertension from the Nephrology Department and Emergency Department in a single center during January 2016 and December 2017 were prospectively enrolled and divided into MHT ( n  = 48) and non-MHT ( n  = 36) subgroups according to target organ evaluation. Forty healthy controls were recruited. Serum soluble Fms-like tyrosine kinase-1 (sFlt-1) levels and plasma ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13) activity were examined at baseline and 12-month follow-up. Renal endpoints were defined as a significant decrease in the estimated glomerular filtration rate (eGFR) of more than 40% or the occurrence of end-stage renal disease.

RESULTS

Serum sFlt-1 levels were persistently elevated in MHT. Baseline serum sFLT-1 levels were correlated with plasma ADAMTS13 activity and markers of target organ damage. Plasma ADAMTS13 activity was reduced in both MHT and non-MHT patients and recovered to the normal range at 12-month follow-up. During an average follow-up time of 53 ± 13 months, the restoration of reduced ADAMTS13 activity was correlated with the improvement of kidney function and independently reduced the risk of renal endpoints.

CONCLUSIONS

Abnormal angiogenesis and endothelial damage are involved in the pathophysiology of hypertensive emergency. Evaluation of ADAMTS13 and sFlt-1 may help in the diagnosis and assessment of MHT. Recovery of ADAMTS13 predicts better renal outcome in patients with hypertensive emergencies.

Cardiac Morphology, Function, and Left Ventricular Geometric Pattern in Patients with Hypertensive Crisis: A Cardiovascular Magnetic Resonance-Based Study

(1) Background: Altered cardiac morphology and function are associated with increased risks of adverse cardiac events in hypertension. Our study aimed to assess left ventricular (LV) morphology, geometry, and function using cardiovascular magnetic resonance (CMR) imaging in patients with hypertensive crisis. (2) Methods: Patients with hypertensive crisis underwent CMR imaging at 1.5 Tesla to assess cardiac volume, mass, function, and contrasted study. Left ventricular (LV) function and geometry were defined according to the guideline recommendations. Late gadolinium enhancement (LGE) was qualitatively assessed and classified into ischemic and nonischemic patterns. Predictors of LGE was determined using regression analysis. (3) Results: Eighty-two patients with hypertensive crisis (aged 48.5 ± 13.4 years, and 57% males) underwent CMR imaging. Of these patients, seventy-eight percent were hypertensive emergency and twenty-two percent were urgency. Diastolic blood pressure was higher under hypertensive emergency (p = 0.032). Seventy-nine percent (92% of emergency vs. 59% of urgency, respectively; p = 0.003) had left ventricular hypertrophy (LVH). The most prevalent LV geometry was concentric hypertrophy (52%). Asymmetric LVH occurred in 13 (22%) of the participants after excluding ischemic LGE. Impaired systolic function occurred in 46% of patients, and predominantly involved hypertensive emergency. Nonischemic LGE occurred in 75% of contrasted studies (67.2% in emergency versus 44.4% in urgency, respectively; p < 0.001). Creatinine and LV mass were independently associated with nonischemic LGE. (5) Conclusion: LVH, altered geometry, asymmetric LVH, impaired LV systolic function, and LGE are common under hypertensive crisis. LVH and LGE more commonly occurred under hypertensive emergency. Longitudinal studies are required to determine the prognostic implications of asymmetric LVH and LGE in hypertensive crisis.

Revisiting malignant hypertension: rationale and design of the 'HAMA cohort', on behalf of the ESH working group 'hypertension and the kidney'

BACKGROUND

Malignant hypertension has not disappeared and is associated with a poor prognosis. Yet, so far, it has received limited attention from the medical community. Guidelines are mainly based on expert consensus and low quality evidences.

METHOD

We set up a prospective, multicenter, observational cohort of patients with malignant hypertension. We collect at admission medical history, demographic data, ongoing treatment, clinical parameters, symptoms, care pathways, target organ status and at discharge and during follow up treatment administrated, adverse events, blood pressure level, target organ status. We aim to recruit 500 patients with malignant hypertension in 5 years, with a 5-year follow-up. Our primary objective is to assess the 5 years prognosis of these patients.

DISCUSSION

The HAMA (Hypertension Arterielle MAligne, meaning malignant hypertension) registry aims to describe the epidemiology and to assess the prognosis of malignant hypertension in a contemporary multidisciplinary cohort, with emphasis on the diversity of current management and care pathway among the different medical specialties. It may help improving our pathophysiological knowledge, and pave the way to update the definition of this particular form of hypertension. The multidisciplinary network developed in the wake of this project is expected to facilitate the set up therapeutic trials, laying the ground for evidence-based recommendations.

Association between long-term pulse pressure trajectories and risk of end-stage renal diseases in incident malignant hypertensive nephropathy: a cohort study

OBJECTIVE

The trajectories of pulse pressure (PP) might affect the prognosis of malignant hypertensive nephropathy (MHN). We aimed to describe the association between PP trajectories and the future risk of end-stage renal disease and to identify and compare the associated patient characteristics of any distinct trajectory patterns in MHN patients.

METHODS

Patients with newly diagnosed biopsy-proven MHN 2010-2015 were included. Latent class growth analysis was applied to the PP measured over 3 years prior to biopsy to identify distinct trajectories. Concurrent systolic blood pressure, diastolic blood pressure, plasma creatinine, and 24-h urine protein measurements for each trajectory group were modelled using generalized estimating equations. The risk of end-stage renal disease (with kidney replacement therapy as a proxy) was estimated using Logistic regression.

RESULTS

Two hundred three patients were included (median-age 34 years, and 19.7% female). A two-group cubic model was optimal, with trajectories distinguished by the rate of PP and absolute level at final measurement. Trajectory Group-1 (n = 84) was characterized by 'first-increased-then-decreased' PP and trajectory Group-2 (n = 119) was characterized by 'first-decreased-then-increased' PP over 3 years prior to biopsy. Systolic and diastolic blood pressures, plasma creatinine, and 24-h urine protein were differed by the trajectory group. Baseline characteristics differed substantially between trajectory groups. Compared with Group-1, Group-2 had a 66% greater risk of developing into end-stage renal disease in the subsequent 3 years.

CONCLUSIONS

Two distinct 3-year trajectories for PP exist with MHN. Early introduction of intensive antihypertensive treatment might delay the development of end-stage renal disease among patients with malignant hypertension.

Clinical value of multiorgan damage in hypertensive crises: A prospective follow-up study

Hypertensive crises are associated with high rates of target organ complications and poor outcomes. A recent shift from the definition of malignant hypertension to hypertension-multiorgan damage (MOD) contributes to the diagnosis and management of hypertensive crises. Here, we prospectively included 166 adult (≥18 years old) patients with hypertensive crises (blood pressure >180/120 mm Hg). Target organs and causes of hypertension were assessed. Patients who were diagnosed with malignant hypertensive retinopathy, the absence of malignant hypertensive retinopathy but the presence of damage to at least 3 organs, and the absence of both retinopathy and MOD were classified as the malignant hypertension (n = 48), hypertension-MOD (n = 42), and hypertension without MOD (n = 76) groups, respectively. Patients were followed to evaluate renal and cardiovascular prognoses. At baseline, patients with malignant hypertension had worse renal function, higher level of albuminuria, and more severe microvascular damage than those with hypertension-MOD. Both had similar proportions of malignant arteriolar nephrosclerosis (83% vs 64%), left ventricular hypertrophy (90% vs 88%), abnormal repolarization (71% vs 60%), and left ventricular dysfunction (12% vs 21%). At the twenty months of follow-up, both the malignant hypertension and hypertension-MOD groups had similar blood pressure control rates and proteinuria. Both groups had worse renal outcomes than the hypertension without MOD group (P = .002). Patients with hypertension-MOD (HR = 0.67, [95% CI: 0.30-1.46], P = .31) had similar renal event-free survival than patients with MHT after adjustments of age, sex, blood pressure, and proteinuria control. These results suggest that in hypertensive crises, both malignant hypertension and hypertension-MOD have impact on adverse renal outcomes.

Correlations Between Interleukin-11 Expression and Hypertensive Kidney Injury in a Rat Model of Renovascular Hypertension

BACKGROUND

Interleukin-11 (IL-11) is a pleiotropic cytokine of the interleukin-6 family. Recent studies revealed its crucial role in the development of cardiovascular fibrosis. In this study we examined IL-11 expression levels in the heart and the kidney exposed to high blood pressure in renovascular hypertensive rats and their correlations to fibrotic markers and kidney injury.

METHODS

Two-kidney, one-clip renovascular hypertension (2K1C) was induced in rats. IL-11 expression was measured by real-time polymerase chain reaction in the left ventricle and the right kidney. The correlation of cardiac IL-11 expression with biomarkers of renal fibrosis was assessed. We further investigated IL-11 expression in 2K1C rats grouped into rats with malignant vs. nonmalignant hypertension (distinguishing criteria: weight loss, number of fibrinoid necrosis, and onion skin lesions).

RESULTS

Thirty-five days after clipping, mean arterial pressure was significantly increased in 2K1C. Renal IL-11 expression was elevated in 2K1C. In the heart there was only a trend toward higher IL-11 expression in 2K1C. IL-11 in the kidney in 2K1C correlated with the expression of transforming growth factor (TGF)-β1/2, collagens, fibronectin, osteopontin, as well as tissue inhibitors of metalloprotease 1/2. There were also correlations of IL-11 with tissue collagen expansion, number of activated fibroblasts and serum creatinine, but no correlation with mean arterial pressure. Renal expression of IL-11 was highest in rats with malignant hypertension.

CONCLUSIONS

Renal IL-11 expression of renovascular hypertensive rats is markedly increased and correlates with profibrotic markers and loss of function and might therefore serve as a biomarker for the severity of hypertensive nephrosclerosis.

Malignant hypertension: diagnosis, treatment and prognosis with experience from the Bordeaux cohort

BACKGROUND

Malignant hypertension, the most severe form of hypertension, is defined by high blood pressure and acute ischemic organ damage. It has a worse prognosis than other forms of hypertension, especially in black patients. New tools to assess organ damage, especially that of the heart and brain, are now available and may contribute to a better evaluation of these patients. This report improves knowledge of the characteristics of involved organs to facilitate diagnosis and to evaluate the effectiveness of our treatment protocol.

METHOD

The Bordeaux registry, started in 1995, recruited 168 patients. In addition to evaluations of their eyes and kidneys, these patients had a systematic evaluation of their hearts with ECG and echocardiography and, since 2007, a systematic brain MRI. Blood pressure was lowered with a protocol based on blockers of the renin-angiotensin system started at a very low-dose with forced titration over 48 h. Only an oral route was used for antihypertensive medication.

RESULTS

Systematic MRIs found significant brain damage in 93% of patients. Heart involvement was highly prevalent: 82% had left ventricular mass more than 60 g/m, and 56% had systolic dysfunction (estimated by global longitudinal strain). Renal involvement and thrombotic microangiopathy were respectively present in 55 and 15% of patients. Median follow-up was 48 months. Renal survival at 5 years was 90.8%, similar to other studies.

CONCLUSION

Malignant hypertension is a systemic disease causing severe damage to the brain, heart, kidneys and eyes, even in absence of symptoms. Renin-angiotensin system blockers seem to be the cornerstone of treatment.

ESC Council on hypertension position document on the management of hypertensive emergencies

Hypertensive emergencies are those situations where very high blood pressure (BP) values are associated with acute organ damage, and therefore, require immediate, but careful, BP reduction. The type of acute organ damage is the principal determinant of: (i) the drug of choice, (ii) the target BP, and (iii) the timeframe in which BP should be lowered. Key target organs are the heart, retina, brain, kidneys, and large arteries. Patients who lack acute hypertension-mediated end organ damage do not have a hypertensive emergency and can usually be treated with oral BP-lowering agents and usually discharged after a brief period of observation.

Malignant Hypertension Revisited-Does This Still Exist?

Malignant or accelerated hypertension is the most severe form of hypertension, defined clinically by very high blood pressure (diastolic above 130 mm Hg) accompanied by bilateral retinal hemorrhages and/or exudates, with or without papilledema. The aim of this review is to discuss if malignant hypertension still poses a clinically relevant entity and to highlight the diagnostic challenges of this form of hypertension. The substantial improvement in prognosis in patients with malignant hypertension over the last decades is well documented, but there is no strong evidence to suggest a significant change in its incidence. In fact, with the growing population and improving life expectancy, malignant hypertension is likely to become even more prevalent worldwide, especially in the developing countries with less advanced health care services. Despite simple diagnostic criteria of malignant hypertension, the diagnoses may be difficult in many patients. Malignant hypertension patients often have the diagnosis established only when the target organ damage occur. Furthermore, retrospective diagnosis is problematic, as malignant hypertensive retinopathy gradually resolves over a relatively short period of time, while persistent target organ damage will, however, lead to the development of complications and much poorer prognosis than in nonmalignant hypertension patients. Certainly, malignant hypertension still poses a clinically relevant and challenging form of hypertension and its possibility should be always considered during the assessment of patients with poorly controlled hypertension.