Hypertension
-
Comparative Study
Effect of compensated renal dysfunction on approved heart failure markers: direct comparison of brain natriuretic peptide (BNP) and N-terminal pro-BNP.
Brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) are markers of heart failure. Although renal dysfunction may increase plasma concentrations, the magnitude of this effect has not been assessed in a head-to-head comparison between the clinically approved tests. We assessed the effect of compensated renal dysfunction on BNP (Triage BNP; Biosite) and NT-proBNP (elecsys proBNP; Roche) in 469 randomly selected stable outpatients after myocardial infarction (MI; Monitoring Trends and Determinants in Cardiovascular Diseases [MONICA] register Augsburg) who were characterized with respect to renal function (glomerular filtration rate [GFR]; Cockroft method) and left ventricular (LV) ejection fraction (EF) and mass (2D echocardiography). ⋯ When binary cut-off values were stratified according to the absence or presence of renal dysfunction (BNP 75 pg/mL and 125 pg/mL, respectively; NT-proBNP 100 pg/mL and 350 pg/mL, respectively), the predictive power of both markers for the detection of LVD increased substantially. BNP and NT-proBNP are almost similarly influenced by mild-to-moderate renal dysfunction. Renal dysfunction is a potential cause of elevated marker concentrations in the absence of LVD, and cut-off concentrations should be stratified according to renal function.
-
Isolated systolic hypertension is a common condition in individuals aged older than 60 years. However, isolated systolic hypertension has also been described in young individuals, although the mechanisms are poorly understood. We hypothesized that in young adults, isolated systolic hypertension and essential hypertension have different hemodynamic mechanisms and the aim of this study was to test this hypothesis in a cohort of subjects from The ENIGMA Study. ⋯ We have demonstrated that in young adults, isolated systolic hypertension and essential hypertension arise from different hemodynamic mechanisms. Isolated systolic hypertension appears to result from an increased stroke volume and/or aortic stiffness, whereas the major hemodynamic abnormality underlying essential hypertension is an increased peripheral vascular resistance. Long-term follow-up of these individuals is now required to determine whether they are at increased risk compared with age-matched normotensive individuals.
-
Based on individual patient data, we performed a quantitative overview of trials in hypertension to investigate to what extent lowering of systolic blood pressure (SBP) and diastolic blood pressure (DBP) contributed to cardiovascular prevention. We selected trials that tested active antihypertensive drugs against placebo or no treatment. Our analyses included 12,903 young (30 to 49 years of age) patients randomized in 3 trials and 14,324 old (60 to 79 years of age) and 1209 very old (> or =80 years of age) patients enrolled in 8 trials. ⋯ Furthermore, in patients with a larger-than-median reduction in SBP, active treatment consistently reduced the risk of all outcomes irrespective of the decrease in DBP or the achieved DBP. These findings remained consistent if the achieved DBP averaged <70 mm Hg. In conclusion, our overview suggests that antihypertensive drug treatment improves outcome mainly through lowering of SBP.
-
Case Reports
Management of hypertension in the setting of autonomic failure: a pathophysiological approach.
We discuss 2 cases presenting clinically with disabling orthostatic hypotension and severe supine hypertension. This is a common presentation of autonomic failure, and one that challenges conventional treatment. ⋯ The differential diagnosis and treatment of orthostatic hypotension is discussed from a pathophysiological approach. Understanding of the underlying mechanisms of disorders of the autonomic nervous system is fundamental for an effective management of these patients and provides insight into more common disorders such as essential hypertension.
-
Comparative Study
Prediction of heart failure by amino terminal-pro-B-type natriuretic peptide and C-reactive protein in subjects with cerebrovascular disease.
B-type natriuretic peptide (BNP) and C-reactive protein (CRP) are elevated in persons at risk for congestive heart failure (CHF). However, limited data are available directly comparing BNP-related peptides and CRP in persons at risk of CHF. To evaluate amino terminal-pro-BNP (NT-proBNP) and CRP, separately and together, for assessment of risk of CHF, we performed a nested case-control study of the 6105 participants of the Perindopril pROtection aGainst REcurrent Stroke Study (PROGRESS), a placebo-controlled study of a perindopril-based blood pressure-lowering regimen among individuals with previous stroke or transient ischemic attack (TIA). ⋯ NT-proBNP and CRP predicted CHF in subjects receiving perindopril-based therapy. We conclude that NT-proBNP and CRP are independent predictors of CHF risk after stroke or TIA. Moreover, NT-proBNP and CRP may be markers of mechanisms of CHF pathogenesis distinct from those responsive to angiotensin-converting enzyme inhibitor-based therapy.