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Biomedical subjects

C Palombo

Publications and source records attributed to C Palombo.

At least 55 records · Page 3Linked to original sources

[Relationship of Doppler indexes of left ventricular filling and exertion tolerance].

The aim of this study was to evaluate if Doppler indexes of left ventricular filling are related to exercise capacity. Since a correlation between left ventricular filling pattern and causal blood pressure has been recently reported along a wide range of pressure values, a group of subjects with blood pressure ranging from normal to severely elevated values was studied. Twenty-four subjects (11 normotensives, 13 mild to severe hypertensive patients) underwent an echo-Doppler study and a maximal multistage cycloergometric exercise test. Since the cycloergometric test was limited by fatigue or dyspnea in all subjects, exercise duration was used as an effort tolerance index. Echocardiographic indexes of systolic function resulted normal in all subjects. Significant relationships with exercise duration were found for several indexes of left ventricular filling (A peak: r = -.743, p < .0001; A/E ratio: r = -.606, p < .005; early filling fraction: r = .639, p < .001). Exercise time was also significantly related to casual blood pressure, both systolic and diastolic. The relationships between transmitral blood flow and exercise capacity seem to indicate that an impairment of ventricular relaxation (as indicated by the progressive increase of atrial contribution) is associated with a decreased exercise tolerance, possibly because a progressively lower activation of Frank-Starling mechanism. Diastolic function thus seems to be able to affect exercise tolerance even in subjects with normal systolic function and blood pressure ranging from normal to severely elevated values.

Adult↗

Electrocardiographic signs of atrial overload in hypertensive patients: indexes of abnormality of atrial morphology or function?

Left atrial electrocardiographic (ECG) abnormalities have been reported as common findings in hypertension; however, their relationships with atrial anatomy are still uncertain. In addition, in arterial hypertension several studies demonstrated an abnormal left ventricular filling. The aim of this study was to investigate the relationships of the ECG signs of left atrial abnormality to atrial anatomy and left ventricular filling as evaluated by pulsed-wave (PW) Doppler in a group of patients with uncomplicated essential hypertension. To this end, 53 untreated essential hypertensive patients (age 44 +/- 8 years; blood pressure 160.5 +/- 21.5/104.7 +/- 13.5 mm Hg) underwent a complete 12-lead ECG and a PW Doppler study of the transmitral flow velocities. The ECG criteria of left atrial abnormality were: P wave wider than 0.12 (or 0.10) second or higher than 0.25 mV in lead II; P wave/PR segment ratio (Macruz index) greater than 1.6 in lead II; and P wave terminal forces in lead V1 equal to or more negative than 0.04. Echocardiographic measurements were made according to American Society of Echocardiography (ASE) convention. Doppler parameters of left ventricular filling were measured as E and A peak velocity, A/E ratio, and the ratio between the velocity-time integral under the E peak and that of the whole diastolic flow, which represents the rapid filling fraction (RFF). At least one ECG sign of atrial abnormality was present in 34 patients (64%); the Macruz index gave the most common ECG index of atrial abnormality (31 patients).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Casual, ambulatory and stress blood pressure: relationships with left ventricular mass and filling.

In arterial hypertension, casual blood pressure seems to be weakly related to the level of cardiac involvement. The aim of the present study was to assess if blood pressure during ambulatory monitoring, and during different stress tests, is a stronger predictor of anatomical and functional changes observed in hypertensive heart disease. To this aim, 29 untreated patients with borderline-to-moderate essential hypertension underwent an echo-Doppler evaluation to determine left ventricular thickness and mass. From transmitral flow, the ratio between late and early filling velocities (A/E ratio) was used to assess left ventricular diastolic behaviour. On the same day that ultrasonic study was carried out, we also measured a set of casual blood pressures; conducted a mental arithmetic test (standardized series of mental subtractions); a handgrip test (30% of maximum voluntary contraction for 3 minutes); and performed noninvasive ambulatory monitoring of blood pressure (Spacelabs 5200). Significant relationships were observed between left ventricular mass and both night-time systolic blood pressure (r = 0.46, P less than 0.02) and peak systolic blood pressure during mental stress (r = 0.39, P less than 0.05). The A/E ratio was significantly associated with casual systolic and diastolic blood pressure (r = 0.45, P less than 0.02; r = 0.38, P less than 0.05, respectively); day-time diastolic blood pressure (r = 0.47, P less than 0.02); night-time systolic and diastolic blood pressure (r = 0.44, P less than 0.05; r = 0.42, P less than 0.05 respectively); and peak systolic blood pressure during the mental arithmetic test (r = 0.44, P less than 0.05). Our results seem to confirm the presence of a relationship between causal blood pressure and left ventricular filling. Moreover, the transmitral flow seems to be dependent on both mean levels of blood pressure on ambulatory monitoring and systolic blood pressure during mental stress. As concerns left ventricular mass, the correlations observed support the weakness of the links between blood pressure and left ventricular anatomy.

Adult↗

Left ventricular filling: relationship with arterial blood pressure, left ventricular mass, age, heart rate and body build.

The relationships of age, heart rate, body build and, in particular, of arterial blood pressure and left ventricular mass to several Doppler indexes of diastolic function were evaluated in a series of 80 subjects with a wide range of blood pressure levels (106-217/68-144 mmHg). Body build and age results were inversely correlated to the indexes, reflecting the early contribution to left ventricular filling, whereas the increase in heart rate was associated with an increase in late diastolic contribution. Strong correlations (in most instances, P less than 0.0001) were observed with arterial blood pressure and left ventricular mass: the increase of these parameters was associated with a decrease of early transmitral peak velocity (E peak) and of early filling fraction, with an increase of late diastolic transmitral peak velocity (A peak) and of A:E ratio and, finally, with an increase of both deceleration time of E peak and acceleration time to A peak. Blood pressure or left ventricular mass were also confirmed as strong predictors of nearly all the Doppler-derived diastolic indexes by stepwise multiple regression analysis. When the subjects were subdivided into quintiles according to diastolic blood pressure and the average values of the five subgroups were compared, age, heart rate and body build results were similar in the quintiles while diastolic blood pressure increased stepwise by 10 mmHg. Analysis of variance showed significant differences for all the indexes of left ventricular filling except deceleration time of and acceleration time to E peak (P less than 0.05 to P less than 0.0001) and almost all the echo-Doppler indexes showed a linear trend with diastolic blood pressure and left ventricular mass.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Impaired insulin action on skeletal muscle metabolism in essential hypertension.

Previous studies have shown that essential hypertension is frequently associated with insulin resistance. The tissues responsible for this metabolic alteration have not been defined. We tested the hypothesis that skeletal muscle is the site of insulin resistance of essential hypertension with the use of the perfused forearm technique. Eight hypertensive (age 42 +/- 3 years, body mass index 27 +/- 1 kg/m2, intra-arterial mean blood pressure 126 +/- 4 mm Hg) and seven normotensive (age 48 +/- 3 years, body mass index 26 +/- 1 kg/m2, mean blood pressure 95 +/- 4 mm Hg) male volunteers were studied. After glucose ingestion (40 g/m2), normal glucose tolerance in the patients was maintained at the expense of a heightened plasma insulin response, suggesting the presence of insulin resistance. During graded, local (intra-arterial) hyperinsulinemia encompassing the physiological range (12-120 milliunits/l), glucose uptake by forearm tissues was significantly (p less than 0.03) reduced in the hypertensive subjects as compared with the controls at each of five insulin steps, by 43% on the average. In addition, forearm lactate and pyruvate release were significantly less stimulated in the hypertensive than in the normotensive group (p less than 0.01 for both), presumably as a consequence of the decreased glucose influx. Forearm exchange of oxygen, carbon dioxide, lipid substrates (free fatty acids, glycerol, and beta-hydroxybutyrate), and potassium were similar in the hypertensive and normotensive groups in the basal state. Insulin had no effect on oxygen consumption, carbon dioxide production, and respiratory quotient in either study group, whereas it stimulated free fatty acids, glycerol, and potassium uptake to the same extent in the hypertensive and normotensive groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Calcium antagonists: accounts on new perspectives of their use and an update on side effects].

Although calcium antagonists are drugs which have been introduced relatively recently, their use is already so widespread, at least in the treatment of cardiovascular diseases as to represent one of the main therapies for diseases such as ischaemic cardiopathy, arterial hypertension, and, to a lesser extent, arrhythmias. Together with the development of clinical applications, deeper insight has been gained into the clinical and experimental pharmacology of these drugs. The authors of this review concentrate their attention on some of the less frequently discussed aspects of calcium antagonists. On the one hand, they describe some "nonprimary" uses of these drugs, both in the cardiovascular and in other therapeutic fields, which already receive confirmation from relatively solid experimental data. On the other hand, they review the side effects and some pharmacological interactions of calcium antagonists, both of which should be held in due consideration, seeing that these drugs are widely employed in clinical practice and their use often requires prolonged, intensive treatment. The most common side effects are described, together with others relatively less well known ones, and outline is given of potential undesirable effects on the cardiovascular as well as on other systems.

Adult↗

Assessment of pretreatment laparotomy in patients with cervical carcinoma prior to radiotherapy.

One hundred fifty-five patients with cervical cancer not amenable to radical surgery underwent selective, paraaortic lymphadenectomy and exploratory laparotomy prior to the initiation of radiotherapy. Fifty-one patients underwent transperitoneal lymphadenectomy; the remainder had the procedure performed using the extraperitoneal approach. Twenty-six patients (17%) were found to have metastatic disease to the paraaortic lymph nodes. The incidence of paraaortic metastases increased with advancing clinical stage. Twenty-four of the 26 patients were treated with extended-field radiotherapy which did not exceed 5100 cGy to the paraaortic region. Twenty-three percent of the patients with positive paraaortic nodes had documented intraperitoneal tumor. Two- and five-year actuarial survival rates for patients with paraaortic metastases were 35 and 27%, respectively. Approximately 4.6% of patients undergoing a selective paraaortic lymphadenectomy derived therapeutic benefit from the information supplied by the procedure. Using a Cox model, tumor histology, status of the paraaortic lymph nodes, tumor size, and presence of intraperitoneal disease were statistically significant prognostic factors in patient survival. Tumor size and presence of intraperitoneal disease were major predictors of patient survival.

Adenocarcinoma↗

Echo-Doppler assessment of left ventricular filling in borderline hypertension.

The aim of this study was to evaluate left ventricular anatomy and diastolic function in borderline essential hypertension. To this aim, 16 borderline hypertensive patients underwent echocardiographic and pulsed-wave Doppler evaluation. As control groups, 20 normotensive controls and 20 patients with established hypertension were evaluated by the same procedure. By the Doppler assessment of transmitral blood flow, the following indices of left ventricular diastolic function were obtained: early (E) and late (A) peak flow velocity, late to early velocity ratio (A/E), early filling fraction (EFF) and acceleration and deceleration times of early and late flow peaks. Borderline hypertensives had an interventricular septum and posterior wall thickness significantly higher than normotensives and lower than established hypertensives. As regards the diastolic indexes, borderline hypertensive patients had significantly higher A peaks (P less than .02) and A/E ratios (P = .05) and lower EFF (P less than .02) as compared to normotensive controls. No significant differences were on the other hand observed with established hypertensive patients. This resultant diastolic pattern was independent of age, as indicated by the analysis of age-matched subgroups. The presence of diastolic function changes in borderline hypertension confirms the early appearance of this kind of abnormality in hypertensive heart disease. On the other hand, the finding of increased left ventricular wall thickness in borderline hypertensives does not allow us to conclude that, as suggested by other authors, diastolic function changes in the early stage of hypertension are independent on anatomical modifications.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Reduced cardiovascular efficiency and increased reactivity during exercise in borderline and established hypertension.

In this study, exercise capacity was evaluated in patients with borderline and established, uncomplicated, essential hypertension as compared to normal subjects. To this aim, the response of blood pressure, heart rate and cardiac work to a multi-stage exercise test was investigated by analyzing the results of linear regression fitting of cardiovascular parameters (ie, heart rate, systolic blood pressure and rate-pressure product (RPP)) versus time of exercise. Compared to normal patients, both essential and borderline hypertensive patients had a shorter average duration of exercise test (ie, a decreased exercise capacity), always negative for transient myocardial ischemia. This was in spite of a mild increment of maximal RPP (+19% and +10% v normal patients, respectively). Reduction of exercise duration in borderline and established hypertensive patients was related to the higher RPP at rest (+26% and +56% related to normal patients, respectively) and to the steeper slopes (rates of increment) of heart rate systolic pressure and RPP during exercise. Interestingly, in the overall population of normal and hypertensive subjects, the slopes of heart rate and RPP were directly correlated with basal blood pressure. In conclusion, these data indicate a decreased exercise tolerance in both established and borderline hypertensive patients without documented myocardial ischemia. This abnormality, which appears to be due to a disproportional increment during exercise not only of systolic pressure but also of heart rate, could reflect abnormalities in the autonomic control of heart function.

Adult↗

Different determinants of left ventricular filling in normotensive subjects and essential hypertensive patients.

The aim of the study was to evaluate the relationships between left ventricular (LV) filling and age, heart rate (HR), blood pressure (BP), and LV mass in three groups of subjects with different casual blood pressure. Twenty normotensive subjects (NT: age 39.2 +/- 7.2; BP 121.6 +/- 11.3/77.7 +/- 7.5 mm Hg), 16 borderline hypertensives (BH: age 38.6 +/- 9.2; BP 138.2 +/- 11.6/91.7 +/- 9.4 mm Hg), and 20 essential hypertensives (EH: age 44.5 +/- 8.3; BP 165.7 +/- 14.8/107.6 +/- 11.4 mm Hg) underwent 2D Echo evaluation and PW Doppler measurements of transmitral blood flow velocity. In NT, the Doppler indexes of LV filling showed significant correlations only with age and heart rate (age v E peak: r = .68 P less than .001; v A peak: r = .45, P less than .05; v A/E: r = .78, P less than .001. Heart rate v A peak: r = .78, P less than .001, v A/E: r = .74, P less than .001, respectively). Similar but weaker relationships were observed in BH. On the contrary, EH showed no significant correlations with age or heart rate, but with both systolic blood pressure (SBP), diastolic blood pressure (DBP), and LV mass (SBP v A peak: r = .49, P less than .05; v A/E: r = .68, P less than .001; DBP v E peak: r = 44, P less than .05; v A/E: r = .58, P less than .01. Left ventricular mass v E peak: r = .45, P less than .05; v A/E: r = .51, P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Microalbuminuria and casual and ambulatory blood pressure monitoring in normotensives and in patients with borderline and mild essential hypertension.

Several reports suggest that urinary albumin excretion may be elevated in patients with essential hypertension and that this index may be a good predictor for cardiovascular complications. The aim of this study was to compare 24-hour urinary albumin excretion in a group of normotensives, borderline, and untreated mild hypertertensives and to assess, in a subgroup of them, the possible relations between microalbuminuria and arterial blood pressure. Fifteen normotensives, 16 borderline, and 19 mild hypertensive patients were studied. Slightly but significantly higher values of microalbuminuria were observed in the mild hypertensives compared to the other two groups. In 21 borderline and mild hypertensive patients 24-hour microalbuminuria was related to casual blood pressure and noninvasive ambulatory blood pressure monitoring. A significant correlation was found between microalbuminuria and average day-time diastolic blood pressure. Our data suggest that albumin excretion is slightly increased in mild arterial essential hypertension; the direct association between microalbuminuria and arterial diastolic blood pressure during daily activities seems to confirm a pathophysiological link between transcapillary protein escape and arterial blood pressure that warrants further studies.

Adult↗

Seasonal influences on blood pressure in high normal to mild hypertensive range.

To investigate the seasonal influences on various arterial blood pressure measurements, 22 subjects in the high normal to mild hypertensive range were examined twice following the same protocol. In one group (13 subjects), measurements were first done in warm conditions and repeated 5-7 months later in cold conditions; in the second group (nine subjects) a reverse sequence was followed. Blood pressure was measured under casual conditions during a hand grip exercise test, mental arithmetic test, and submaximal multistage bicycle exercise test; during the following 24 hours, blood pressure was measured serially with a noninvasive ambulatory blood pressure recorder. Daily outdoor maximum and indoor laboratory temperatures were also obtained. In the cold season, significantly higher values (on the average by 5-10 mm Hg, p less than 0.01) were obtained in both groups for mean diastolic daytime blood pressure. For other measurements, a trend toward higher values in the cold season was observed in both groups, although statistical significance was not obtained in all instances. For nighttime measurements, irrespective of the seasonal sequence, lower values were observed in the second session. Significant correlations were found between the differences in the average daytime ambulatory blood pressures and the corresponding changes of daily maximum outdoor temperatures after 5-7 months. These observations indicate that arterial blood pressure may be strongly influenced by environmental temperature. This phenomenon should be taken into account both in the evaluation of the individual hypertensive patients and in the design and analysis of studies on arterial hypertension, especially when ambulatory blood pressure techniques are employed.

Adolescent↗

Long-term reproducibility and evaluation of seasonal influences on blood pressure monitoring.

The aim of this study was to evaluate the long-term reproducibility and the possible seasonal influences on casual blood pressure and ambulatory blood pressure monitoring in patients with borderline or mild arterial hypertension. Two sets of measurements were performed at 6-month intervals, one set in the warm and one in the cold season, using the same protocol, consisting of measurements of casual and ambulatory blood pressures, together with the recording of outdoor temperatures. Casual blood pressure was measured by an automatic recorder and 24-h ambulatory blood pressure monitoring was performed by a non-invasive device. For the selected intervals, the reproducibility of most pressure measurements was low; in addition, casual diastolic pressure and 24-h systolic and diastolic pressures were significantly higher in the cold than in the warm season. Taken together, these findings confirm and extend the results obtained in several large-scale studies and support the importance of taking environmental temperature into account, not only in epidemiological studies but also in small-scale studies and probably even in the individual patients, especially when using integrated evaluations by ambulatory monitoring.

Adult↗

Cardiovascular reactivity to physical and psychologic stress during long-term treatment with nitrendipine in essential hypertension.

Nitrendipine is a second-generation dihydropyridine calcium antagonist selective for hypertension. The aim of this study was to assess whether, in addition to reduce resting blood pressure, nitrendipine also affects the cardiovascular reactivity to physical and psychologic stress. Ten essential hypertensive patients, out of treatment for at least 2 weeks, underwent a symptom-limited dynamic maximal exercise and a mental arithmetic stress test (MAT) after placebo (1 week) and 1 and 5 weeks of active treatment with nitrendipine (20 mg q.i.d.). To evaluate the cardiovascular response to exercise and its changes during treatment, the slope of the regression line (if statistically significant) of the blood pressure, heart rate, and rate-pressure product (RPP) values against workload were considered, together with exercise capacity, blood pressure, and pressure-rate product at the peak of maximal exercise. During mental stress, indexes of stroke volume (SVI), cardiac output (COI), and peripheral resistance (TPRI) were obtained by Doppler transcutaneous aortovelography (TAV). Resting systolic and diastolic BP were significantly reduced during treatment. The average length of exercise was 7.3, 7.64, and 8.0 min after, respectively, placebo, 1, and 5 weeks of treatment. Peak systolic and diastolic BP, peak RPP, and RPP slope were consistently decreased after treatment, significantly for peak DBP and RPP. During mental arithmetics, a significant increase of BP and HR and a decrease of SVI were observed on placebo; both BP and SVI responses disappeared after 5 weeks on nitrendipine, whereas the HR increase was unchanged. Peak values of COI and TPRI during MAT were significantly increased and decreased, respectively, after nitrendipine, whereas basal values showed similar changes, but not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Renal scintigraphic captopril test in the diagnosis of renovascular hypertension.

Angiotensin converting enzyme (ACE) inhibitor-induced renal failure has been reported in bilateral renal artery stenosis and in stenosis in solitary kidneys, but not in unilateral renal artery stenosis. In these patients, however, a functional impairment of the kidney ipsilateral to the stenosis can often be detected after ACE inhibition by scintigraphic techniques employing glomerular radionuclide tracers like 99mTc-diethylenetriamine pentaacetic acid (DTPA). Dynamic renal scintigraphy with 99mTc-DTPA before and 1 hour after administration of captopril, 25 mg (renal scintigraphic captopril test; RSCT), was performed in a selected series of 39 hypertensive subjects with suspected renovascular hypertension. Changes in glomerular filtration rate induced by captopril on the individual kidney were estimated by assessing the early (120-180 seconds) DTPA uptake by the kidney. Values were expressed as the ratio between the kidney with the lower uptake and the contralateral one in 34 patients and as the ratio of the kidney counts to the injected dose in five patients with solitary kidneys, aortic coarctation, or both. Compared with precaptopril values, postcaptopril uptake decreased markedly in 14 subjects (-62.42 +/- 30.94 [SD]%; range, -25 to -100%) and decreased modestly or even increased in the other 25 (+0.57 +/- 9.83%; range, +28 to -13%). Of the 14 subjects considered to be RSCT-positive diagnostic workup revealed either established (10) or strongly suspected (2) renal artery stenosis in 12 and aortic coarctation in 2 subjects. In another patient with established renovascular hypertension, results of the RSCT were negative when performed in the supine position but became positive when repeated in the sitting position.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Changes in renal function during physical and mental effort.

Aim of the study was to evaluate the renal responses to physical and mental effort in essential hypertension by means of a non-invasive radioisotopic method. Renal uptake rate of Tc99m-DMSA was evaluated in 10 subjects. Starting from 5 to 15 minutes after dose injection counts over the kidney region were acquired by means of a gamma-camera time-activity curves were obtained for each kidney. In non-stimulated patients DMSA uptake rate increased regularly; in the remaining cases both isometric exercise and mental effort induced an abrupt reduction of the uptake rate which increased again after the end of the test. Although the relation of DMSA uptake rate to renal function is not yet fully understood, we tentatively interpret these results as indicating blood flow reductions during these stressful conditions.

Humans↗