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The article examines the connection between resistant hypertension, aldosterone, and persistent intravascular volume expansion. Characteristics of 279 consecutive patients with resistant hypertension and 53 control subjects are evaluated in the study. Participants of the study are observed for plasma aldosterone concentration, plasma renin activity, aldosterone to renin ratio, brain-type natriuretic peptide, atrial natriuretic peptide, and 24-hour urinary aldosterone, cortisol, sodium, and potassium values while continuously doing a routine diet. It concludes that patients with resistant hypertension have higher aldosterone levels and intravascular volume expansion than those patients with controls.

Resistant hypertension is defined as blood pressure (BP) that remains uncontrolled in spite of the use of ≥3 antihypertensive medications. Stricter BP goals, higher obesity rates, older age, and increased use of exogenous BP-elevating substances are related to an increasing prevalence of resistant hypertension. The evaluation of patients with resistant hypertension is focused on identifying contributing and secondary causes of hypertension, including hyperaldosteronism, obstructive sleep apnea, chronic kidney disease, renal artery stenosis, and pheochromocytoma. Hyperaldosteronism is now recognized as the most common cause of resistant hypertension, and all patients with resistant hypertension should be screened with a plasma aldosterone/renin ratio even if the serum potassium level is normal. Treatment includes removal of contributing factors, appropriate management of secondary causes, and use of effective multidrug regimens. Recent studies indicate that the addition of spironolactone to standard treatment induces significant BP reduction in most patients with resistant hypertension. [ABSTRACT FROM AUTHOR]

The extra-renal effects of aldosterone on left ventricular (LV) structure and function are exacerbated by increased dietary sodium in persons with hypertension. Previous studies demonstrated endothelial dysfunction and increased oxidative stress with high salt diet in normotensive salt-resistant subjects. We hypothesized that increased xanthine oxidase (XO), a product of endothelial cells, is related to 24-h urinary sodium and to LV hypertrophy and function in patients with resistant hypertension (RHTN). The study group included persons with RHTN (n = 91), defined as a blood pressure > 140/90 mmHg on ≥ 3 medications at pharmacologically effective doses. Plasma XO activity and 24-h urine were collected, and cardiac magnetic resonance imaging (MRI) was performed to assess LV function and morphology. Sixty-seven normotensive persons on no cardiovascular medications served as controls. A subset of RHTN (n = 19) received spironolactone without salt restriction for six months with follow-up XO activity measurements and MRI analyses. XO activity was increased two-fold in RHTN vs. normal and was positively correlated with LV mass, LV diastolic function, and 24-h urinary sodium. In RHTN patients receiving spironolactone without salt restriction, LV mass decreased, but LV diastolic function and XO activity did not improve. Baseline urinary sodium was positively associated with rate of change of LV mass to volume ratio and the LV E/A ratio. These results demonstrate a potential role of endothelium-derived oxidative stress and excess dietary salt in the pathophysiology of LV hypertrophy and diastolic dysfunction in persons with RHTN unaffected by the addition of spironolactone. Image 1 • XO activity is increased in resistant hypertension. • XO activity is related to left ventricular hypertrophy and diastolic dysfunction. • XO activity is related to 24-h urinary sodium. [ABSTRACT FROM AUTHOR]

Background: Torsion shear angle φ is an important measure of left ventricular (LV) systolic and diastolic functions. Here we provide a novel index utilizing LV normalized torsion shear angle (...) volume (...) loop to assess LV diastolic functional properties. We defined the area within ... loop as torsion hysteresis area, and hypothesized that it may be an important global parameter of diastolic function. We evaluated the ... changes to increased ... during early diastole (...) as a potential measure of LV suction. Methods: Sixty resistant hypertension patients (HTN), forty control volunteers were studied using cardiovascular magnetic resonance with tissue tagging. Volumetric and torsional parameters were evaluated. Results: HTN demonstrated concentric remodeling with preserved ejection fraction. HTN had significantly decreased normalized early filling rate, early diastolic mitral annulus velocity and E/A (1.33 ± 1.13 vs. 2.19 ± 1.07, P < 0.0001) vs. control. Torsion hysteresis area was greater (0.11 ± 0.07 vs. 0.079 ± 0.045, P < 0.001) and peak ... at early diastole was higher (10.46 ± 8.51 vs. 6.29 ± 3.85, P = 0.002) than control. Torsion hysteresis area was significantly correlated with E/A (r = −0.23, P = 0.025). Thirteen HTN patients had both E/A ratio < 1.12 (Control mean E/A-1SD) and torsion hysteresis area > 0.12 (Control mean torsion hysteresis area + 1SD). Conclusions: Torsion hysteresis area and peak early diastolic ... were significantly increased in hypertensive concentric remodeling. The ... loop takes into account the active and passive recoil processes of LV diastolic and systolic phases, therefore provides a new global description of LV diastolic function. [ABSTRACT FROM AUTHOR]