Elisa Testa

Orthostatic hypotension: evaluation and treatment.

Orthostatic hypotension (OH) may be dependent upon various neurogenic and non-neurogenic disorders and conditions. Neurogenic causes include the main autonomic failure syndromes, primary (multiple system atrophy, pure autonomic failure, and autonomic failure associated with Parkinsons disease) and secondary (central nervous system diseases, peripheral neuropathies and systemic diseases). Non-neurogenic causes of OH include cardiac impairment, fluid and electrolyte loss, vasodilatation, and old age. A number of drugs may also cause OH, through their vasoactive action or by interfering with the autonomic nervous system. Symptoms of OH are debilitating, often confining patients to bed, and longitudinal studies have shown that OH increases the risk of stroke, myocardial ischemia and mortality. The therapeutic goal is to decrease the incidence and severity of postural symptoms, rather than restore normotension. In non-neurogenic OH, treatment of the underlying cause may be curative. In neurogenic OH a combination of non-pharmacological and pharmacological measures is often needed. Patient education and non-pharmacological measures represent the first step; among these interventions, fluid repletion and physical countermanoeuvres have been proven very effective. Pharmacological treatment comprises a number of agents acting on blood vessels, on blood volume or with other pressor mechanisms. The drugs most currently used are fludrocortisone and midodrine. Fludrocortisone expands the extravascular body fluid volume and improves alpha-adrenergic sensitivity. Midodrine is a peripheral, selective alpha1-adrenergic agonist that causes arterial and venous vasoconstriction. Despite the wide use of these drugs, multicentre, randomised and controlled studies for the treatment of OH are still scarce and limited to few agents and groups of patients. Pharmacological management of OH substantially improves the quality of life of patients, although it may be problematic. The development of supine hypertension and subsequent congestive heart failure should be avoided, especially in those patients with a pre-existing cardiovascular risk, such as in diabetes or ischemic heart disease.

Comparison among Different Screening Tests for Diagnosis of Adolescent Hypertension

The diagnosis of childhood hypertension based upon percentile tables proposed by the international guidelines is complex and often a cause of underdiagnosis, particularly among physicians who have not had specific training in the field of adolescent hypertension. The use of a simple and accurate screening test may improve hypertension diagnosis in adolescents. The aim of our study is to compare the different screening methods currently used in the literature to improve the diagnosis of childhood hypertension. We have conducted a cross-sectional population-based study of 1412 Caucasian adolescents among students of public junior high schools of Turin, Italy. In this population we have defined the hypertensive status with four different screening tests: BPHR, Somus equations, Ardissino, and Kaelber methods. Finally, we compared the diagnostic accuracy of the 4 screening tests with the gold standard. Our analysis identifies in BPHR the test which combines ease of use and diagnostic accuracy.

Appropriateness of Referral to a European Society of Hypertension Center of Excellence

In the European health care system, the general practitioner is a patient’s primary medical contact and point of referral to specialist care. Although current guidelines strongly recommend the pharmacologic treatment of hypertension in patients, adequate blood pressure (BP) control is achieved in only <30% of patients. To improve the care of the hypertensive patient, the ‘‘Hypertension Specialist’’ was introduced by the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC 7). Referral to a specialist is recommended for patients with resistant hypertension, severely complicated hypertension, and if a secondary form of hypertension is suspected. The aim of our study was to determine the appropriateness, in terms of efficiency and effectiveness, of referrals to specialized centers by general practitioners. We reviewed the computer-stored data of 9874 Caucasian hypertensive patients (aged 3–101 years, 4794 men, 5080 women) consecutively referred by general practitioners to our hypertension clinic from 1989 to 2008. The first visit and the 5 follow-up visits were considered for each patient to assess and compare the patient’s management by the general practitioner and the specialist. BP values were classified and resistant hypertension was defined according to 2007 European Society of Hypertension (ESH) ⁄ European Society of Cardiology (ESC) guidelines. Both pediatric hypertension and patients with comorbidities were included in the study. We subdivided the analysis into 3 different periods (1989–1994, 1995–2001, and 2002–2008), chosen on the basis of the publication years of the main hypertension guidelines. The time spent by doctors and patients for inappropriate referral was calculated. Means and standard deviations for descriptive variables and proportions for categoric variables were calculated. One-way analysis of variance (continuous variables) and chi-square test (categorical variables) were used to analyze data. The mean age was significantly increased between the first and the last periods but the body mass index was unchanged. With regards to lifestyle, a significant decrease in smoking was observed with time although a lack of physical activity persisted. BP values (161 ⁄ 99– 150 ⁄ 90 mm Hg, P<.0001) and the average number of antihypertensive drugs taken at the baseline visit (1.32 in the first period and 1.18 in the last, P<.0001) decreased with time. At the baseline visit, 16% of referred patients had controlled BP at the baseline visit and this significantly increased over the 3 periods (5.8% and 23.8% in the first and last periods, respectively) (Table I). Regarding pharmacologic treatment, in the last period only 57.6% of patients were already treated with one drug when referred to our unit, compared with 74.7% in the first period. Overall, 51.63% of patients met at least one of the criteria for referral, with a higher percentage during the mid-period but with a marked reduction over the last period (41.54%). Of patients who were incorrectly referred, 40% were untreated, 31% were taking monotherapy, and only 29% took >1 antihypertensive drug. The most common reasons for referral were complicated hypertension and comorbidities, followed by resistant hypertension. The referral process has impli-

Efficacy of antihypertensive treatment based on plasma renin activity: An open label observational study

Abstract Background. We investigated the extent of blood pressure (BP) reduction and control (<140/90 mmHg) in patients treated with appropriate or inappropriate drugs according to their plasma renin activity (PRA) level (natriuretic drugs and renin–angiotensin system blockers for low-renin and high-renin hypertension, respectively). Patients and methods. One hundred and seventy Caucasian untreated hypertensive patients (61 females), aged 18–70 years, participated to the study. Patients with secondary hypertension, diabetes or established cardiovascular or renal disease were excluded. The physician prescribed an antihypertensive monotherapy chosen among all drug classes, unaware of patients PRA levels. We compared effect of an inappropriate or appropriate drug, evaluating BP values after a month of treatment. Results. Rate of BP control was not significantly higher in patients treated with an appropriate drug than the others (38% vs 29%, p=0.24). However, in a regression analysis, final diastolic BP (DBP) was lower in subjects treated with an appropriate drug (β=−2.84, p=0.03). Conclusions. The present study does not clearly support the use of PRA in a general population of hypertensive patients to optimize BP control. However, the greater efficacy of a drug appropriate to PRA in reducing DBP may be clinically helpful in young hypertensive patients. Future studies are warranted to evaluate if PRA determination enhances the therapeutic success in patients with predominantly high values of DBP.

[PP.23.13] ANALYSIS OF ELIGIBILITY CRITERIA FOR RENAL SYMPATHETIC DENERVATION

Objective: Resistant hypertension (RH) is a rare condition that affects approximately 10% of hypertensive population, its defined as blood pressure (BP) > 140/90 mmHg despite three full doses antihypertensive drugs including a diuretic. True RH is confirmed when pseudo-hypertension, secondary hypertension or poor adherence are excluded. Percutaneous radio-frequency catheter-based renal sympathetic denervation (DRN) is one of the most used invasive treatments for these patients. The goal of the study is to assess the percentage of eligibility to DRN and analyze the exclusion criteria in a group of resistant hypertensive patients. Design and method: We retrospectively analyzed data of 35 patients (63% female) referred to our Hypertension Unit between June 2011 and June 2014. We considered eligible for DRN subjects with office systolic blood pressure > = 160 mmHg and patients with severe hypertension treated with fewer drugs for poly-intolerances/allergies. Secondary hypertension form and white coat hypertension were excluded. Patients with confirmed true resistant hypertension underwent CT angiography in order to check the renal anatomic criteria of eligibility to the DRN. Results: 35 caucasian patients (63% female) referred to our Hypertension Unit between June 2011 and June 2014 for DRN assessment. At the first evaluation median systolic and diastolic office BP were 179 ± 25 mmHg and 105 ± 20 mmHg; six month later, after appropriate changes in lifestyle and drug therapy, systolic/diastolic office BP was reduced of 18/8 mmHg (p < 0.05). In the most of cases, patients had to BP control with introduction of antialdosteronic (35%). In our sample, 27 patients were considered unsuitable for the DRN for many reason: blood pressure control with optimization of drug therapy (52%), evidence of white coat effect (22%), secondary hypertension (22%), lack of true resistant hypertension (18%), absence of consent to the procedure (29%). Conclusions: A carreful patients selection in Specialistic Center is necessary before DRN; indeed frequently a good BP control is obtained with appropriate drug therapy changes and exclusion of secondary forms.

Effects of Antihypertensive Drugs on the Renin-Angiotensin System in Essential Hypertension

A standardized approach to antihypertensive pharmacological therapy taking into account the pathophysiological mechanism of hypertension is not yet available. Laragh and colleagues have proposed a model based on the concept that the two final determinants of blood pressure are the volume status and the renin-angiotensin-aldosterone system. This model allows patients to be divided into two categories based on plasma renin activity (<0.65 or >0.65 ng/mL) and with a different primary target for a specific therapy. In Laragh’s opinion, all antihypertensive drugs could be divided into two groups according to their mechanism of action: drugs that block the activity of the renin-angiotensin system (R drugs, such as β-adrenoceptor antagonists [β-blockers], ACE inhibitors, angiotensin II type 1 receptor antagonists [angiotensin receptor blockers] and centrally acting antihypertensive drugs) or drugs that increase renal sodium excretion (V drugs, such as diuretics, α-adrenoceptor antagonists [α-blockers] or calcium channel blockers). This article reviews the mechanisms underlying this antihypertensive drug classification.