Extracellular vesicles in cardiomyopathies: A narrative review.

Extracellular vesicles (EVs) are membrane-bound particles released by all cells under physiological and pathological conditions. EVs constitute a potential tool to unravel cell-specific pathophysiological mechanisms at the root of disease states and retain the potential to act as biomarkers for cardiac diseases. By being able to carry bioactive cargo (such as proteins and miRNAs), EVs harness great potential as accessible "liquid biopsies", given their ability to reflect the state of their cell of origin. Cardiomyopathies encompass a variety of myocardial disorders associated with mechanical, functional and/or electric dysfunction. These diseases exhibit different phenotypes, including inappropriate ventricular hypertrophy, dilatation, scarring, fibro-fatty replacement, dysfunction, and may stem from multiple aetiologies, most often genetic. Thus, the aims of this narrative review are to summarize the current knowledge on EVs and cardiomyopathies (e.g., hypertrophic, dilated and arrhythmogenic), to elucidate the potential role of EVs in the paracrine cell-to-cell communication among cardiac tissue compartments, in aiding the diagnosis of the diverse subtypes of cardiomyopathies in a minimally invasive manner, and finally to address whether certain molecular and phenotypical characteristics of EVs may correlate with cardiomyopathy disease phenotype and severity.

Updates in Small Interfering RNA for the Treatment of Dyslipidemias.

PURPOSE OF REVIEW: Atherosclerotic cardiovascular disease (ASCVD) is still the leading cause of death worldwide. Despite excellent pharmacological approaches, clinical registries consistently show that many people with dyslipidemia do not achieve optimal management, and many of them are treated with low-intensity lipid-lowering therapies. Beyond the well-known association between low-density lipoprotein cholesterol (LDL-C) and cardiovascular prevention, the atherogenicity of lipoprotein(a) and the impact of triglyceride (TG)-rich lipoproteins cannot be overlooked. Within this landscape, the use of RNA-based therapies can help the treatment of difficult to target lipid disorders. RECENT FINDINGS: The safety and efficacy of LDL-C lowering with the siRNA inclisiran has been documented in the open-label ORION-3 trial, with a follow-up of 4 years. While the outcome trial is pending, a pooled analysis of ORION-9, ORION-10, and ORION-11 has shown the potential of inclisiran to reduce composite major adverse cardiovascular events. Concerning lipoprotein(a), data of OCEAN(a)-DOSE trial with olpasiran show a dose-dependent drop in lipoprotein(a) levels with an optimal pharmacodynamic profile when administered every 12 weeks. Concerning TG lowering, although ARO-APOC3 and ARO-ANG3 are effective to lower apolipoprotein(apo)C-III and angiopoietin-like 3 (ANGPTL3) levels, these drugs are still in their infancy. In the era moving toward a personalized risk management, the use of siRNA represents a blossoming armamentarium to tackle dyslipidaemias for ASCVD risk reduction.

Hypertension in a cohort of obese Caucasian children and adolescents and its association with glycometabolic indices: A proposed screening tool.

BACKGROUND AND AIM: Hypertension (HTN) is common among obese children and adolescents and increases their cardiovascular risk later in adulthood. The aim of the study was to evaluate the prevalence of HTN identified by office blood pressure (BP) measurement and ambulatory BP monitoring (ABPM) in a cohort of obese children and adolescents and its association with anthropometric and glycometabolic indices. METHODS AND RESULTS: Seventy consecutive obese Caucasian children and adolescents aged 7-16 years were enrolled. Patients underwent ABPM, echocardiogram and carotid ultrasonography. Sex- and age-adjusted logistic multivariable analysis models were used to assess the association between HOMA-IR, HOMA-ß, QUICKI with HTN at ABPM. Receiver Operation Curve (ROC) analysis with Youden J statistics was used to identify the optimal HOMA-IR, HOMA-ß and QUICKI cut-off to predict HTN at ABPM. Hypertensive office BP was found in 25.7% of obese patients. ABPM diagnosed HTN in 34.9% of patients: 20.6% of obese patients had masked HTN (MHTN), and 12.7% had white coat HTN (WCH). Hypertensive obese patients (according to ABPM) had higher HOMA-IR and HOMA-ß, and a lower QUICKI than normotensive subjects. HOMA-IR, HOMA-ß and QUICKI predicted HTN at ABPM in obese patients in age- and sex-adjusted logistic multivariable models. Optimal cut-offs to predict HTN at ABPM in obese patients were: HOMA-IR ≥ 3.30, HOMA-ß ≥ 226.7 and QUICKI <0.33, with high sensitivity. CONCLUSIONS: A sequential testing strategy applying office BP and glycometabolic indices can identify hypertensive obese pediatric patients with high diagnostic accuracy and potentially reducing costs. This strategy needs validation in an external and larger cohort.

Systematic review and meta-analysis on coronary calcifications in COVID-19.

Chest CT is valuable to detect alternative diagnoses/complications of COVID-19, while its role for prognostication requires further investigation. Non-pulmonary radiological findings such as cardiovascular calcifications could increase the predictivity of clinical outcomes of COVID-19 patients beyond pulmonary involvement. Several observational studies have reported mixed results on the role of coronary calcifications in COVID-19 patients as a predictor of hospitalization, ventilatory support, and mortality. The purpose of the study is to systematically review the available evidence on the predictive role of cardiovascular calcifications in SARS-CoV2 disease. The meta-analysis confirms the prognostic significance of coronary calcifications on hospital mortality, and coronary calcifications (CAC ≠ 0) were associated with an OR for mortality of 2.19 (95% CI 1.36-3.52). CAC was neutral on respiratory outcomes, but it was associated with an increased trend of cardiovascular events. Coronary calcium appears as a promising biomarker imaging even in short-term outcomes (MACEs, hospital mortality) in a non-cardiovascular disease such as Sars-CoV2 infection. Further large studies are needed to confirm promising results of this imaging biomarker in non-cardiovascular disease.

Echocardiographic changes in anorexia nervosa: a pathophysiological adaptation or a disease?

Anorexia Nervosa is one of the most common form of eating disorders. Cardiac involvement occurs in approximately 80% of patients. Few reports focused on the association between body weight fluctuations and echocardiographic abnormalities, considering linear measurements. We describe echocardiographic and clinical features among male and female patients with anorexia nervosa and the effect of weight gain on these parameters. We performed a single center, retrospective study of patients followed at a dedicated multidisciplinary Unit. The study population consisted of 81 patients, mean age 25 ± 11 years, 94% female. Median body mass index was 14.4 kg/m2 (25th-75th percentile 12.7-15.6 kg/m2). Patients with body mass index below the median value had more often pericardial effusion, smaller left ventricular mass and left ventricular end-diastolic volume and thinner interventricular septum. However, when indexed to body surface area, left ventricular mass and volumes were within the normal range in 90% of population. Patients with pericardial effusion showed mitral valve abnormalities and lower values of white blood cells and platelets, although within normal limits. Presence of pericardial effusion was not related to inflammatory parameters or low plasma protein levels. In 39 patients who displayed weight gain during a median follow-up of 189 days (25th-75th percentile 47-471), increased left ventricular mass, interventricular septum thickness, white blood cells and platelet count and decreased pericardial effusion were observed. Patients with anorexia nervosa have a specific echocardiographic pattern which seems to be proportional to the body size, suggesting a pathophysiological adaptation to the lack of substrates.

Effect of surgical treatment on myocardial strain in patients with pheochromocytoma and paraganglioma: a mini-review and meta-analysis.

AIM: Information on systolic dysfunction, as assessed by left-ventricular (LV) mechanics, in patients with pheochromocytoma after surgical treatment is scanty. We performed a systematic meta-analysis of speckle tracking echocardiographic studies to provide an updated comprehensive information on this issue. METHODS: The PubMed, OVID-MEDLINE, and Cochrane library databases were analyzed to search for articles published from the inception up to May 31st 2021. Studies were identified using MeSH terms and crossing the following search items: "myocardial strain" "left ventricular mechanics", "speckle tracking echocardiography", "systolic dysfunction", "pheochromocytoma", and "paraganglioma". RESULTS: A total of 92 surgically treated patients with pheochromocytoma/paraganglioma were included in 3 longitudinal studies. Successful surgical treatment was associated with a decrease in relative wall thickness (SMD - 0.25 ± 0.10, CI - 0.45/- 0.05, p < 0.01) and an improvement in global longitudinal strain (SMD - 0.45 ± 0.10, CI - 0.66/- 0.24, p < 0.0001). The favorable effects of treatment on LV geometry and mechanics were not accompanied by significant changes in ejection fraction (SMD - 0.07 ± 0.10, CI - 0.27/0.12, p = 0.44). CONCLUSIONS: This meta-analysis adds a new piece of evidence, suggesting that surgical treatment of patients with pheochromocytoma impacts favorably on LV geometry and LV mechanics, and, more importantly, the assessment of LV changes in this setting can no longer rely on conventional echocardiographic parameters such as ejection fraction.

Sensitive and quantitative method to evaluate DNA methylation of the positive regulatory domains (PRDI, PRDII) and cAMP response element (CRE) in human endothelial nitric oxide synthase promoter.

Nitric oxide plays a prominent role in the cardiovascular system and much attention has been devoted in the last years on deciphering the regulation of human endothelial nitric oxide synthase (eNOS) expression. Epigenetic-based mechanisms have a key role in the eNOS expression and their pathologic perturbations may have profound effects on the steady state RNA levels in the endothelium. The human eNOS promoter lacks a canonical TATA box and it does not contain a proximal CpG island. A differentially DNA methylated region (DMR) in the native eNOS proximal promoter is involved in gene expression regulation. Here we describe a quantitative, sensitive and cost-effective method that, relying on a novel normalization strategy, allows the quantification of DNA methylation status of the positive regulatory domains (PRDI, PRDII) and cAMP response element (CRE) in human eNOS promoter. This technique will enable to explore the functional relevance of DNA methylation perturbations of eNOS promoter both under pathological and physiological conditions.

Clinic blood pressure, ambulatory blood pressure and cardiac structural alterations in nonagenarians and in centenarians.

scant information is available on the alterations in cardiac structure and function characterizing very elderly people as well as on their relationships to clinic and ambulatory blood pressure (BP) values. In 106 subjects aged 95.3 ± 3.7 years (mean ± standard deviation, 89 nonagenarians and 17 centenarians) in good clinical conditions and living in the municipal house in Milan, we measured, along with standard clinical and laboratory variables, clinic BP, 24-h ambulatory BP and echocardiographic parameters. Forty-five of the recruited subjects were normotensive individuals, whereas 61 were treated hypertensive patients. Subjects with an age greater than 90 years showed clinic systolic (SBP) and diastolic BP (DBP) both within the normal range, with values that for clinic SBP were slightly lower than the corresponding 24-h SBP (120.8 ± 15.9 vs 128.0 ± 16.3 mmHg) and for DBP slightly higher (69.7 ± 8.8 vs 64.9 ± 8.0 mmHg). Daytime average mean BP was slightly lower than night-time average mean BP, indicating the attenuation of the BP reduction during night-time. Left ventricular mass index (LVMI) was increased and significantly related to both 24-h and clinic BP values (r = 0.24, p < 0.04 and r = 0.20, p < 0.05). Thus in nonagenarians and centenarians, abnormalities in left ventricular pattern are of frequent detection and may be related both to the ageing process and to BP load.

Alterations of cardiac structure in patients with isolated office, ambulatory, or home hypertension: Data from the general population (Pressione Arteriose Monitorate E Loro Associazioni [PAMELA] Study).

BACKGROUND: The prevalence and clinical significance of isolated office (or white coat) hypertension is controversial, and population data are limited. We studied the prevalence of this condition and its association with echocardiographic left ventricular mass in the general population of the PAMELA (Pressione Arteriose Monitorate E Loro Associazioni) Study. METHODS AND RESULTS: The study involved a large, randomized sample (n=3200) representative of the Monza (Milan) population, 25 to 74 years of age. Participants in the study (64% of the sample) underwent measurements of office, home, 24-hour ambulatory blood pressure, and echocardiography. Isolated office hypertension was defined as systolic or diastolic values >/=140 mm Hg or >/=90 mm Hg, respectively. Home and ambulatory normotension were defined according to criteria previously established from the PAMELA Study, for example, <132/83 mm Hg (systolic/diastolic) for home and 125/79 mm Hg for 24-hour average blood pressure. Treated hypertensive subjects were excluded from analysis that was made on a total of 1637 subjects. Depending on normotension being established on systolic or diastolic blood pressure measured at home or over 24 hours, the prevalence of isolated office hypertension ranged from 9% to 12%. In these subjects, left ventricular mass index was greater (P<0.01) than in subjects with normotension both in and outside the office. This was the case also for prevalence of left ventricular hypertrophy. Left ventricular mass index and hypertrophy were similarly greater in subjects found to have normal office but elevated home or ambulatory blood pressure ( approximately 10% of the population). CONCLUSIONS: Isolated office hypertension has a noticeable prevalence in the population and is accompanied by structural cardiac alterations, suggesting that it is not an entirely harmless phenomenon. This is the case also for the opposite condition, that is, normal office but elevated home or ambulatory blood pressure, which implies that limiting blood pressure measurements to office values may not suffice in identification of subjects at risk.

Progression of functional and structural cardiac alterations in young normotensive uncomplicated patients with type 1 diabetes mellitus.

OBJECTIVE: We have recently observed that in young, normotensive patients with a type I diabetes mellitus and no macro or microvascular complications, large artery structure and function are already altered. This study has been done to assess whether this condition is also characterized by early alterations in cardiac structure and function, and whether these alterations progress with time. DESIGN AND METHODS: In 56 insulin-treated, normotensive uncomplicated type I diabetic patients (age 35.0 +/- 2 years, means +/- SE) in good metabolic control, left ventricular wall thickness and diameter were measured by echocardiography together with left ventricular ejection fraction and diastolic function E/A (ratio between early and late ventricular filling), before and after 23 +/- 1 months. The same measurements were made in 20 age and sex-matched subjects who served as controls (C). RESULTS: Compared to C, diabetic patients had a significant increase in left ventricular wall (septal plus posterior wall) thickness (+ 8.4%), left ventricular mass index (+ 11%) and h/r ratio (left ventricular wall thickness/ventricular end diastolic diameter, + 16.0%) whereas they showed a reduction of E/A (-6%). In C, all echocardiographic values were unchanged after 2 years. This was the case also for diabetic patients, except for left ventricular ejection fraction and diastolic diameter which showed a significant reduction (-7.2%) and increase (+ 3.8%), respectively, with a reduction of ratio between LV wall thickness and diameter, h/r (-6.8%). CONCLUSIONS: Uncomplicated type I diabetes mellitus is characterized by early structural and functional cardiac alterations. Some of these alterations show a measurable progression within a relatively short time span.

Effects of physical training of the dominant arm on ipsilateral radial artery distensibility and structure.

BACKGROUND: Exercise training induces cardiovascular changes that are both generalized and restricted to the microcirculation of the tissues more actively involved in the exercise itself. Whether the local effect of exercise extends to larger arteries is unknown, however. METHODS: In the right and left upper limb of 17 right-handed subjects performing an asymmetric training of the upper limbs (hammer throwers and baseball players) and 16 age-matched sedentary controls, we continuously measured radial artery diameter, distensibility and wall thickness by an echotracking and a beat-to-beat finger blood pressure device. Arterial distensibility was calculated by the arctangent model of Langewouters and expressed as continuous values from diastolic to systolic blood pressure. Measurements were made: (1) in baseline conditions; (2) after release from prolonged proximal ischaemia; and (3) after an increase in radial artery blood flow caused by a short (4 min) distal ischaemia to determine the endothelial involvement in the training-induced change in arterial distensibility. RESULTS: In athletes the radial artery distensibility was markedly greater in the right than in the left arm, the latter showing values slightly greater than those seen in the two arms of sedentary subjects. In both arms and groups radial artery distensibility increased markedly after prolonged ischaemia, the between arm and group differences being preserved, however. The radial artery response to distal short ischaemia was, on the other hand, similar in the two arms of the athletes, although greater in these subjects than in the sedentary ones. Radial artery wall thickness was greater in the trained than in the untrained arm of athletes, both values being greater than in sedentary subjects. CONCLUSIONS: Asymmetrical training of the upper limbs is accompanied by a greater distensibility of the middle-sized arteries of the more trained side. This is not associated with asymmetrical changes in endothelial structure or function. It is associated with a greater wall thickness in the trained side, suggesting that, at least in part, a training-induced asymmetrical change in wall structure (possibly with a predominance of more distensible tissues such as elastine and smooth muscle) is responsible.

Effects of prolonged immobilization of the limb on radial artery mechanical properties.

Physical training is associated with an increase in arterial distensibility. Whether the effect of training on this variable is evident also for ordinary levels of exercise or no exercise is unknown, however. We have addressed this issue by investigating the effect on radial artery distensibility of prolonged monolateral immobilization of the ipsilateral limb versus the following resumption of normal mobility. We studied 7 normotensive subjects (age, 25.4+/-3.0 years; systolic/diastolic blood pressure, 119+/-9/68+/-6 mm Hg, mean+/-SE) in whom 1 limb had been immobilized for 30 days in plaster because of a fracture of the elbow. At both the day after plaster removal and after 45 days of rehabilitation, radial artery distensibility was evaluated by an echo-tracking device (NIUS-02), which allows arterial diameter to be measured noninvasively and continuously over all pressures from diastole to systole (finger monitoring), with the distensibility values being continuously derived from the Langewouters formula. In both instances, the contralateral arm was used as control. Immediately after removal of the plaster, radial artery distensibility was markedly less in the previously immobilized and fractured limb compared with the contralateral limb (0.4+/-0.1 versus 0.8+/-0.1, 1/mm Hg 10(-3), P<0.05). After rehabilitation, the distensibility of the radial artery was markedly increased in the previously fractured limb (0.65+/-0.1 1/mm Hg 10(-3), P<0.05), whereas no change was seen in the contralateral limb. Thus, complete interruption of physical activity is associated with a marked reduction of arterial distensibility, indicating that even an ordinary level of activity plays a major role in modulation of arterial mechanical properties.

Effects of isolated systolic hypertension and essential hypertension on large and middle-sized artery compliance.

BACKGROUND: Systolic hypertension of the elderly is characterized by a reduction in arterial compliance. Whether and to what extent this involves arteries of various structure and size is not well known. OBJECTIVE: To study carotid and radial artery compliance in systolic hypertension of the elderly, compared to essential hypertension and normotension. METHODS: We investigated 28 elderly patients with systolic hypertension (age 68.6 +/- 1.4 years, mean +/- SE; systolic blood pressure > 160 mmHg and diastolic blood pressure < 90 mmHg) plus 17 age-matched patients with essential hypertension and 15 age-matched healthy normotensive subjects. Radial and carotid artery compliance were evaluated using echotracking techniques. In both arteries compliance was assessed statistically and dynamically, i.e. as compliance values throughout the diasto-systolic pressure range. Measurements included intima-media wall thickness of the radial artery. RESULTS: Compared to normotensive subjects, carotid artery compliance was reduced in essential hypertension and more so in systolic hypertension. However, although in both groups radial artery wall thickness was markedly greater than in the normotensive group, radial artery compliance was markedly reduced in systolic hypertension, but unchanged in essential hypertension. CONCLUSIONS: In systolic hypertension of the elderly the reduction of arterial compliance is marked in both muscular and large elastic arteries, while in elderly essential hypertensives changes in arterial compliance are more heterogeneous, i.e. only carotid artery compliance is reduced. The different effects of these two types of hypertension on arterial mechanics are visible throughout the physiological range of blood pressure and probably accounted for by different alterations in vessel wall structure.

Evidence of functional and structural cardiac abnormalities in cirrhotic patients with and without ascites.

Cirrhosis is associated with cardiovascular abnormalities. Scanty information is available as to whether these include left ventricle diastolic dysfunction and wall thickness increase. To this aim in 27 cirrhotic patients with tense ascites, 17 cirrhotic patients with previous episodes of ascites (not actual), and 11 controls we investigated by echocardiography and echocolor Doppler left ventricle diastolic function (E wave, A wave, E/A ratio, deceleration time of E wave), systolic function (ejection fraction), and wall thickness (left ventricle posterior wall thickness + interventricular septum thickness) along with neurohumoral variables. All measurements (supine position) were repeated after total paracentesis (10.7 +/- 0.6 L of ascites) in ascitic patients. Both in patients with and without ascites E/A ratio was reduced as compared with controls (0.93 +/- 0.07 and 0.97 +/- 0.06 vs. 1.18 +/- 0.08, P < .05) while left ventricle wall thickness was increased (18.6 +/- 0.6 and 20.1 +/- 0.8 vs. 17.2 +/- 0.7, P < .05 and P < .01, respectively), irrespective of the postviral or alcoholic cause of liver disease. In all cirrhotics both right and left atrial and right ventricle diameters were significantly greater. Ejection fraction was slightly but significantly (P < .01) reduced in ascitic patients. Paracentesis induced a reduction of the highly increased basal plasma renin activity, aldosterone, norepinephrine (P < .01), and epinephrine (P < .05) and improved diastolic function (E/A, P < .05). Systolic function was unaffected. Thus, irrespective of ascites and cause, advanced cirrhosis is associated with left ventricle diastolic dysfunction and wall thickness increase. We can speculate that neurohumoral overactivity, known to stimulate cardiac tissue growth, may challenge the heart, promoting fibrosis and exerting a further hindrance to ventricular relaxation in patients with cirrhosis experiencing episodes of ascites.

Effects of chronic ACE inhibition on sympathetic nerve traffic and baroreflex control of circulation in heart failure.

BACKGROUND: In congestive heart failure ACE inhibitors chronically reduce plasma norepinephrine. No information exists, however, on whether and to what extent this reduction reflects a true chronic inhibition of sympathetic outflow and which mechanisms may be responsible. METHODS AND RESULTS: In 24 patients aged 60.3+/-2.0 years (mean+/-SEM) affected by congestive heart failure (New York Heart Association class II) and treated with diuretics and digitalis, we measured mean arterial pressure (Finapres), plasma renin activity and angiotensin II levels (radioimmunoassay), plasma norepinephrine (high-performance liquid chromatography), and muscle sympathetic nerve activity (microneurography at a peroneal nerve) at rest and during baroreceptor stimulation and deactivation caused by stepwise intravenous infusions of phenylephrine and nitroprusside, respectively. In 12 patients measurements were repeated after a 2-month addition of the ACE inhibitor benazepril (10 mg/d P.O.), while in the remaining 12 patients they were performed again after 2 months without any treatment modifications. Benazepril did not alter mean arterial pressure, markedly increased plasma renin activity, reduced plasma angiotensin II, and caused a nonsignificant reduction in plasma norepinephrine. In contrast, muscle sympathetic nerve traffic was significantly reduced (-30.5+/-5.3%, P<.01). This reduction was accompanied by no change in the sympathoexcitatory responses to baroreceptor deactivation but by a marked enhancement of the sympathoinhibitory responses to baroreceptor stimulation (103.5+/-3.4%). CONCLUSIONS: These results provide the first direct evidence that in congestive heart failure chronic ACE inhibitor treatment is accompanied by a marked reduction in central sympathetic outflow. This reduction may depend on a persistent restoration of baroreflex restraint on the sympathetic neural drive.

Combined effects of hypertension and hypercholesterolemia on radial artery function.

Compliance and distensibility of middle-sized conduit arteries are increased in hypertension and reduced in hypercholesterolemia. Despite their frequent association in the same individual, the combined effect of these two conditions on arterial mechanical properties is unknown. We studied four groups of age- and sex-matched subjects: 10 normotensive normocholesterolemic subjects, 10 mild hypertensive normocholesterolemic subjects, 10 mild hypercholesterolemic normotensive subjects, and 10 mild hypertensive and mild hypercholesterolemic subjects. We measured radial artery diameter by an echotracking device and beat-to-beat blood pressure from an ipsilateral finger. Compliance-pressure and distensibility-pressure curves were derived by Langewouters' formula. Between-group comparisons were made by calculating for both compliance and distensibility the integral of the area under the portion of the curve common to the four groups ("isobaric" compliance and distensibility). Blood pressure was similarly elevated in the two hypertensive groups, and serum cholesterol was similarly elevated in the two hypercholesterolemic groups. Compared with values in normotensive normocholesterolemic subjects, isobaric compliance and distensibility were greater in hypertensive normocholesteroclemic (+38% and 47%, respectively) and smaller in normotensive hypercholesterolemic (-6% and -23%) subjects. However, when both hypertension and hypercholesterolemia were present, isobaric compliance and isobaric distensibility were significantly reduced (-26% and -18%, P < .05). Therefore, hypercholesterolemia reverses the effect of hypertension on arterial compliance and causes arterial stiffening, as when present alone.

Primary prevention of cardiovascular disease.

Antihypertensive drug treatment has been shown to significantly decrease cardiovascular morbidity and mortality rates in hypertensive subjects and to reduce the occurrence of major hypertension-related complications, such as stroke, coronary artery disease, congestive heart failure and renal insufficiency. Despite these favorable effects, several issues related to antihypertensive treatment remain to be clarified. This paper will discuss some of these issues, with particular reference to the effects of blood pressure lowering on renal diseases and coronary heart disease. It will also discuss the ongoing clinical trials aimed at clarifying some unsolved issues of antihypertensive treatment. The objective of the International Nifedipine GITS Study Intervention as a Goal in Hypertensive Treatment was to provide information on the effects of calcium antagonist treatment on high blood pressure values and on hypertension-related cardiovascular complications in a high-risk hypertensive population.

Effects of cigarette smoking on carotid and radial artery distensibility.

OBJECTIVE: Cigarette smoking acutely induces a marked increase of blood pressure and heart rate. This is accompanied by a marked reduction of radial artery distensibility. Whether this reflects an alteration of arterial mechanics of large elastic arteries as well is not established, however. DESIGN AND METHODS: In this study we addressed the acute effects of smoking on the stiffness of a peripheral medium-sized muscular artery and a large elastic vessel. We studied seven healthy normotensive smokers (age 28+/-7 years, mean+/-SEM), in the absence of smoking for at least 24 h. Radial artery (NIUS 02) and carotid artery diameter (WTS) were concomitantly acquired beat-to-beat in the 5 min before, during and after smoking of a cigarette containing 1.2 mg of nicotine. Blood pressure and heart rate were concomitantly recorded by a Finapres device. Radial and carotid artery distensibility were calculated according to the Langewouters and Reneman formulae, respectively. Data were collected for consecutive 30 s periods. Statistical comparisons were performed between the three different phases and, within each phase, between 30 s periods. In five subjects the protocol was repeated after 1 week using a stran rather than a cigarette to obtain data under sham smoking. RESULTS: Smoking increased systolic blood pressure by 14%, diastolic blood pressure by 10% and heart rate by 27%. Radial artery diameter was reduced during smoking (-3.7%) and more so after smoking (-14.8%), while carotid artery diameter did not change significantly either during or after smoking. Radial artery distensibility was also significantly reduced only after smoking (-41.3%, P < 0.01), while carotid artery distensibility was significantly reduced both during (-33.3%) and after smoking (-27.2%) (P < 0.01 versus before). No changes in blood pressure, heart rate and arterial wall mechanics were induced by sham smoking. CONCLUSIONS: Acute cigarette smoking reduces distensibility not only in medium-sized but also in large elastic arteries, therefore causing a systemic artery stiffening. The mechanisms of these effects remain to be determined. However, it is likely that adrenergic mechanisms are responsible for the arterial distensibility alterations.

Impaired radial artery compliance in normotensive subjects with familial hypercholesterolemia.

Hypercholesterolemia impairs arteriolar dilatation, but whether the vascular abnormalities accompanying this condition include large artery function is unknown. We addressed this issue in 13 normotensive subjects with familial hypercholesterolemia (serum cholesterol 401.6 +/- 16.9 mg/dl, mean +/- S.E., FHC) and no evidence of atherosclerotic lesions, in whom radial artery (RA) diameter and blood pressure (BP) were measured beat to beat by an echotracking and a Finapres device, respectively. RA compliance (RAC) was derived from the diameter/BP relationship and expressed over the systo-diastolic BP range, both at baseline and after a 12-min brachial artery occlusion. RAC was expressed also as the area under the RAC/BP curve divided for pulse BP. Measurements included maximal forearm blood flow (plethysmography) and minimal forearm vascular resistance (FVR) which were obtained from the values following the 12-min brachial arterial occlusion. Data were collected before and after 6- and 24-month lipid lowering treatment (simvastatin 40 mg/day). Ten age-matched normotensive normocholesterolemic healthy subjects (N) served as controls. Compared to N, baseline RAC was strikingly reduced in FHC (-53.5%, P < 0.01). After ischemia RAC increased significantly and markedly in N (+38.7, P < 0.01), while only a modest and non-significant increase was observed in FHC. Minimal FVR was markedly higher in FHC than in N (3.5 +/- 0.9 vs 1.6 +/- 0.1 units, P < 0.01). In FHC (7 subjects) RAC remained unchanged after 6 months of lipid lowering treatment, but increased markedly (+55.2%, p < 0.05) when treatment was prolonged to 24 months. Lipid lowering treatment also reduced minimal FVR, the effect being significant both after 6 and after 24 months. No changes in RAC and minimal FVR were seen after 6 months in controls. Thus, in subjects with a marked increase in serum cholesterol due to FHC, not only arteriolar dilatation, but also RAC and distensibility are markedly impaired. This impairment can be favourably affected by an effective lipid lowering treatment of long duration.

Angiotensin-converting enzyme inhibition and radial artery compliance in patients with congestive heart failure.

Congestive heart failure is characterized by a clear-cut impairment of arterial compliance of medium-sized arteries, but whether this alteration is irreversible or can be favorably affected by cardiovascular drugs currently used in congestive heart failure treatment is unknown. We studied 9 congestive heart failure patients (New York Heart Association class II; age, [mean +/- SEM] 60.7 +/- 3.3 years) receiving diuretic and digitalis treatment in whom arterial compliance was assessed at the level of the radial artery by an echotracking device capable of measuring the arterial diameter along the entire cardiac cycle. Beat-to-beat arterial blood pressure was concomitantly measured by a Finapres device that allowed diameter-pressure curves and compliance-pressure curves (Langewouters' formula) to be calculated for the entire systolic-diastolic blood pressure range. Arterial compliance was expressed as the area under the compliance-pressure curve normalized for pulse pressure (compliance index). Data were collected before and after 4 and 8 weeks of oral administration of benazepril (10 mg/day). Ten healthy subjects were studied before and after an observational period of 4 weeks (5 subjects) or 8 weeks (5 subjects), and 9 age-matched mildly essential hypertensive subjects studied before and after 4 to 12 weeks of benazepril administration served as control subjects. In congestive heart failure patients, baseline compliance index was significantly less than in normotensive and hypertensive subjects. However, the compliance index showed a marked increase after 4 weeks of benazepril administration (+95.7 +/- 24.9%, P < .05); the increase was also marked after 8 weeks of angiotensin-converting enzyme inhibitor treatment (+77.7 +/- 4.2%, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)