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Biomedical subjects

A Varga

Publications and source records attributed to A Varga.

At least 55 records · Page 3Linked to original sources
PubMed1999

Effects of chronic long-term therapy with calcium antagonists on cytogenetic damage in humans.

OBJECTIVE: To assess whether chronic long-term calcium antagonist therapy may increase genotoxicity, the chromosome aberration test, a widely accepted genotoxic assay, was used ex vivo in peripheral human lymphocytes of patients with or without long-term exposure to calcium antagonist therapy. METHODS AND RESULTS: In a case-control study design, we evaluated 30 ischaemic and/or hypertensive patients (22 males, eight females; age 59.4+/-1.5 years), under chronic calcium antagonist treatment (group I), for more than 3 years (4.4+/-0.34 years) and 30 age-matched subjects, without any previous exposure to calcium antagonists (group II). Venous blood samples were collected from the patients and cultures were set up for cytogenetic analysis by standard methods. For each subject, 100 metaphases were scored. The two groups showed similar values (mean +/- SEM) for percentage aberrant cells (group I 2.6+/-0.3 versus group II 2.5+/-0.3, not significant), percentage structural aberrations (group I 1.9+/-0.3 versus group II 1.8+/-0.2, not significant) and percentage numerical aberrations (group I 0.70+/-0.2 versus group II 0.73+/-0.2, not significant). CONCLUSIONS: Long-term calcium antagonist therapy is not associated with an increased incidence of chromosomal indices of genotoxic damage in humans.

Calcium Channel Blockers↗
PubMed1999

The impact of second harmonic imaging on stress echocardiography reading.

BACKGROUND: Noncontrast harmonic significantly improves overall image quality in echocardiography. The aim of this study was to assess whether harmonic imaging, without contrast, impacts on interobserver variability and diagnostic accuracy of "beginners" in stress echocardiography. METHODS: Images at rest and peak stress were obtained in digitized format in 15 consecutive patients (10 males, 5 females, mean age 66 +/- 9 years) and analyzed by 5 inexperienced observers (stress echo beginners) who were blinded to the imaging modality (standard versus harmonic imaging). Each observer graded the image quality as 1 = uninterpretable up to 5 = excellent, in a total of 240 segments. RESULTS: The mean image quality per segment was 2.9 for conventional technology and increased up to 3.6 for harmonic imaging (p < 0.001). The interobserver agreement (> or = 4 out of 5 readers) rose from 46 to 60%. The percentage of uninterpretable segments was 7.5% at rest and 8.9% at peak stress of conventional imaging, and decreased to 4.6 and 6.5%, respectively (p < 0.05) by second harmonic technology. The unanimous reading of two additional independent expert observers was arbitrarily assumed to be the "gold standard" to verify the accuracy of reading of the 5 beginners. The 5 beginners showed poor diagnostic accuracy with fundamental imaging (73%), and they did not improve with second harmonic imaging (70%, NS vs fundamental). CONCLUSIONS: Noncontrast second harmonic imaging improves image quality over conventional imaging. The improved quality of the image deflated interobserver variability but did not determine per se an improvement in the diagnostic accuracy of nonexperienced readers.

Aged↗
PubMed1999

Safety of ergotamine-ergic pharmacologic stress echocardiography for vasospasm testing in the echo lab: 14 year experience on 478 tests in 464 patients.

BACKGROUND: The safety of ergonovine/ergometrine stress testing for coronary vasospasm when performed outside the cath lab has vigorously been questioned. The aim of this study was to assess the value of ergonovine/ergometrine stress testing performed in the echo lab. METHODS: We retrospectively reviewed the data prospectively collected in the echo lab of the Institute of Clinical Physiology of Pisa (Italy) from January 1, 1985, to October 1, 1998, on 478 tests performed on 464 patients with either ergonovine or ergometrine stress echo testing. By selection, all patients had history of chest pain, consistent with vasospastic angina, negative or ambiguous exercise stress testing, and normal or near normal resting left ventricular function. Ergonovine or ergometrine maleate was injected up to a total cumulative dosage of 0.35 mg, under continuous 12 lead ECG and two-dimensional echo monitoring. RESULTS: There were no death, myocardial infarction, ventricular fibrillation or III degree atrioventricular block. One patient had non-sustained ventricular tachycardia associated with transient ST segment elevation 30 min after the test. Two patients had II degree atrioventricular block, associated with positive echocardiography test and promptly reversed by nitrate administration. Transient regional myocardial dysfunction occurred in 74 patients (15%). Limiting ischemia-independent side effects were present in 13 patients (3%): hypotension in 1, arterial hypertension in 5, nonsustained ventricular tachycardia in 2, and nausea/vomiting in 5. The overall feasibility was 97%. CONCLUSIONS: Pharmacological stress echocardiography with either ergonovine or ergometrine is highly feasible and can be safely performed in the echo lab in properly selected patients in whom coronary vasospasm is suspected. It is often the only way to document coronary vasospasm otherwise missed by conventional noninvasive stress test and even by coronary angiography.

Coronary Angiography↗
PubMed1999

Coronary vasospasm as a source of false positive results during dobutamine echocardiography.

BACKGROUND: Several studies have demonstrated a consistently high sensitivity of dobutamine echocardiography whereas test specificity in these series has been variable. The aim of this study was to evaluate whether coronary vasospasm--elicited by alpha1 adrenoreceptor stimulation--may be a significant source of false positive responses during dobutamine stress. METHODS: From the data bank of four institutions we selected 113 patients (75 males, 38 females, mean age 55 +/- 12 years) with dobutamine echocardiography performed (up to 40 micrograms/kg/min and atropine 1 mg if needed) before a coronary angiography showing normal or near normal (visually assessed stenosis severity < 50%) coronary arteries. The following variables--which were previously reported influencing dobutamine echo specificity--entered the multivariate statistical analysis: age, sex, heart rate at baseline and at peak stress, baseline echo, hypertension, site of asynergy, and spasm at coronary angiography. RESULTS: Twenty-five patients had a positive dobutamine test. The positivity occurred in the left coronary territory in 15 and in the right coronary territory in 10 cases. All the 6 patients with spontaneous spasm during angiography had a false positive stress test result. By multivariate analysis only coronary artery spasm during angiography (p = 0.0015) and history of hypertension (p = 0.0031) were significant predictors of false positive results of dobutamine stress echocardiography. CONCLUSIONS: Coronary artery spasm may be an important source of false positive results during dobutamine stress echocardiography.

Coronary Disease↗
PubMed1998

Softwood hemicellulose-degrading enzymes from Aspergillus niger: purification and properties of a beta-mannanase.

The enzymes needed for galactomannan hydrolysis, i.e., beta-mannanase, alpha-galactosidase and beta-mannosidase, were produced by the filamentous fungus Aspergillus niger. The beta-mannanase was purified to electrophoretic homogeneity in three steps using ammonium sulfate precipitation, anion-exchange chromatography and gel filtration. The purified enzyme had an isoelectric point of 3.7 and a molecular mass of 40 kDa. Ivory nut mannan was degraded mainly to mannobiose and mannotriose when incubated with the beta-mannanase. Analysis by 1H NMR spectroscopy during hydrolysis of mannopentaose showed that the enzyme acts by the retaining mechanism. The N-terminus of the purified A. niger beta-mannanase was sequenced by Edman degradation, and comparison with Aspergillus aculeatus beta-mannanase indicated high identity. The enzyme most probably lacks a cellulose binding domain since it was unable to adsorb on cellulose.

Amino Acid Sequence↗
PubMed1998

Relative role of coronary stenosis severity and morphology in determining pharmacologic stress echo positivity.

Angiographically assessed plaque morphology, not only plaque severity, may affect myocardial vulnerability to ischemia during stress testing. The aim of this study was to evaluate directly, in a head-to-head comparison, the relation between coronary stenosis severity and morphology and pharmacologic stress echo response. From our inpatients echo databank, we selected 68 patients (62 men, mean age 57 +/- 9 years) who had undergone high-dose dipyridamole and high-dose dobutamine-atropine echocardiography, performed within 1 week and in random order, before coronary angiography that showed significant coronary artery disease by selection. There were altogether 121 vessels with visually assessed stenosis >50% in 68 patients. Thirty-three had complex-type and 56 simple-type lesions (according to the Ambrose classification), whereas 32 vessels were occluded. During dobutamine echocardiography there were 51 dyssynergic regions of the left ventricle fed by different coronary arteries in 50 patients and dipyridamole stress was able to induce ischemia in 45 separate regions in 44 patients. The overall agreement between the 2 tests in recognizing ischemia was 76%. Induced ischemia was associated with greater quantitatively assessed stenosis severity for both dipyridamole (positive, 70 +/- 12% vs negative, 63 +/- 12% area reduction; p <0.05) and dobutamine (positive, 68 +/- 12% vs negative, 63 +/- 12% area reduction; p <0.05). The simple-type stenosis was more frequently identified with dobutamine (46%) versus dipyridamole (21%, [p <0.01]), whereas the complex-type stenosis was associated with a trend toward more frequent positivity of dipyridamole (55%) versus dobutamine (36%), p = 0.13. Adenosinergic stress positivity is affected not only by plaque severity, but also by plaque morphology, whereas adrenergic stress positivity is affected by plaque severity, not by plaque morphology.

Adult↗
PubMed1998

Phosphatidylethanol in blood as a marker of ethanol consumption in healthy volunteers: comparison with other markers.

Phosphatidylethanol is a "pathological" phospholipid, formed via the action of phospholipase D only in the presence of ethanol. The present study was made to elucidate how different levels and patterns of alcohol intake affect blood levels of phosphatidylethanol in comparison with other markers of abuse. We used a new HPLC-evaporative light-scattering detection technique for phosphatidylethanol quantitation. This method had a total coefficient of variation of <20% at the detection limit of 0.2 nmol, equaling 0.8 micromol/liter of whole blood. Two groups were studied. (a) Five healthy volunteers were given 32 to 47 g of ethanol in a single dose, to give blood ethanol levels of approximately 25 mmol/liter after 30 to 60 min. Phosphatidylethanol, carbohydrate-deficient transferrin (CDT), and blood ethanol were measured before and after the intake. (b) Twelve student volunteers were studied during a 3 week period of prolonged alcohol consumption (total estimated intake: 1334 +/- 488 g, mean +/- SD) and phosphatidylethanol, serum-CDT, gamma-glutamyltransferase, and blood ethanol were measured at the start of the period (day 1) and twice at the end of the period (days 18 and 21). In group (a), no phosphatidylethanol was detected at any time after ethanol dosage/intake. In group (b), no blood phosphatidylethanol or blood ethanol could be demonstrated at the start, and serum-CDT was below the discrimination limit (1.3%) in all persons. No phosphatidylethanol was detected in those four persons with the lowest intake (742 +/- 150 g). However, the remaining eight persons had detectable levels of phosphatidylethanol (1.0 to 2.1 micromol/liter), and these had a higher total intake (1630 +/- 389 g). There was a statistically significant (p = 0.02) increase in serum CDT for 3 weeks. However, only 3 of 12 persons increased above the discrimination limit. The present results indicate that a substantial alcohol intake is needed to elevate blood phosphatidylethanol. In comparison with serum-CDT, blood phosphatidylethanol appears more sensitive.

Adult↗
PubMed1997

The elusive link between coronary lesion morphology and dobutamine stress echocardiography results. The EDIC (Echo Dobutamine International Cooperative) Study Group.

BACKGROUND: Coronary lesion angiographic morphology of the complex type is associated to enhanced susceptibility to ischemia during vasodilator adenosinergic stress testing and attributed to the reduced vasodilatory capacity of the damaged endothelium. Whether coronary lesion morphology can also influence the results of adrenergic pharmacologic stress test remains unknown. The aim of our study was to assess the relationship between coronary plaque morphology and dobutamine-atropine stress echocardiography (DASE) results. METHODS AND RESULTS: We analyzed DASE (up to 40 mcg/kg/min plus atropine) and coronary angiography data of 42 patients with single vessel disease and no totally occluded vessel at angiography. 7 patients had angina, 35 had previous infarction. A diagnostic DASE was performed in all patients within 1-10 (mean 4.7 +/- 3.4) days before coronary angiography. An angiographic lesion was considered complex when irregular borders and/or intraluminal lucencies, suggestive of ulcer and/or thrombus were present. According to the angiographic lesion morphology (Ambrose classification), 2 groups were identified: Group I, with simple lesion; Group II with complex lesion. The two groups were similar for number of patients (n = 21), age (I = 55 +/- 11 vs II = 53 +/- 7 years, p = ns), coronary stenosis severity expressed as % diameter reduction (I = 77 +/- 14 vs II = 78 +/- 15%, p = ns), presence of previous infarction (I = 17 vs II = 18 pts, p = ns). No difference was found in the prevalence of positivity between the two groups (I = 72 vs II = 62%, p = ns). The two groups achieved a similar peak dobutamine dose (I = 32 +/- 9 vs II = 33 +/- 9 mcg/kg/min, p = ns) and peak Wall Motion Score Index (I = 1.5 +/- 0.26 vs II = 1.45 +/- 0.28, p = ns). CONCLUSIONS: In patients with non occlusive single vessel disease, coronary morphology of complex type is not associated with greater vulnerability to dobutamine induced ischemia.

Adult↗
PubMed1997

Changes in left ventricular mass during treatment with minoxidil and cilazapril in hypertensive patients with left ventricular hypertrophy.

Attainment of the regression of hypertension-associated left ventricular hypertrophy (LVH) seems to be a desirable goal of blood pressure (BP)-reducing therapy. Since antihypertensive drugs of differing types may exhibit markedly different abilities to modulate LVH, we examined the effects of the angiotensin-converting enzyme inhibitor cilazapril, and the potassium channel activator minoxidil, alone or in combination with each other, on the left ventricular mass (LVM) in patients with severe essential hypertension who had LVH detected by echocardiography. All patients received the same base therapy of bopindolol and guanfacine. After a run-in period, they were treated with: (1) cilazapril (n = 10); (2) minoxidil, combined with a diuretic (n = 10); or (3) both cilazapril and monoxidil (n = 6) for 12 months. The LVM index (LVMI; LVM per body surface area) was estimated every 3 months by means of echocardiography. Each kind of therapy decreased the arterial pressures to a similar degree. The 1-year treatment with the cilazapril-based regimen resulted in a significantly diminished LVMI (from a mean +/- s.d. of 173 +/- 38 to 152 +/- 22 g/m2; P < 0.05). On the other hand, the minoxidil-based therapy led to a significant increase in LVMI (from 148 +/- 19 to 170 +/- 35 g/m2; P < 0.05). There were no significant LVMI changes in patients receiving the combined, cilazapril + minoxidil-based treatment (172 +/- 34 vs the pretreatment 183 +/- 54 g/m2). The results confirm that long-term treatment with cilazapril is effective both in reducing BP and in reducing LVM. In spite of yielding a satisfactory reduction of BP, minoxidil therapy, even in combination with a diuretic and a beta-blocker, may lead to an aggravation of pre-existing LVH; this effect of minoxidil could be prevented by the simultaneous administration of cilazapril.

Adult↗
PubMed1997

Autonomic dysfunction in systemic sclerosis: time and frequency domain 24 hour heart rate variability analysis.

To evaluate the autonomic nervous control of the heart in patients with systemic sclerosis (SSc), spontaneous heart rate variability was investigated by means of time-domain and spectrum analysis of 24 h ECG ambulatory recordings in 30 SSc patients (four males, aged 45.2 +/- 9 yr, mean +/- S.D., range 27-60) and 30 age-matched healthy subjects. A significantly higher heart rate (P < 0.01) and lower circadian and spectral indices of heart rate variability (P < 0.01) were observed in SSc patients, compared with controls. A predictive value of age (P = 0.002), tachycardia (P = 0.002), circadian heart rate variability (P = 0.0025) and spectral power values (P = 0.005) for patient mortality was found. Moreover, the relative risk of death was higher (P = 0.05) in older subjects with circulating anti-Scl70. These abnormalities, detectable by a feasible, non-invasive diagnostic approach, indicate the presence of autonomic cardiac neuropathy in SSc patients.

Activities of Daily Living↗
PubMed1997

Protection of the renal artery in nephron-sparing surgery. I. Pathomorphological study.

It is necessary to clamp the renal artery for some time in renal surgery to preserve the organ. Not only the renal parenchyma but also the wall of the clamped renal artery may be damaged due to known ischaemic-reperfusion causes. Regional venous renal hypothermia induced by intracellular solutions (Sacks II, Euro-Collins) could provide protection against damage of the vessel wall caused by reperfusion or clamping in our experiments, in cases of clamping for 30 minutes, probably because it also ensured the cooling of the surface of the vessel wall. Similar vasoprotective effect could be achieved by systematic antioxidant treatment (MTDQ-DS) and regional renal hypothermia given in combination. Harmful effects of 45-minute clamping could be best avoided by applying antioxidant treatment alone. While there were no significant morphological changes in the renal arteries the persistent endothelial damage may trigger further complications like renal ischaemic condition.

Animals↗
PubMed1997

Protection of the renal artery in nephron-sparing surgery. II. Arterial contractility investigations.

It has been well known that reperfusion following ischaemia may cause functional and structural damage to not only the organ involved but also the blood vessels supplying that organ. As in organ-sparing renal surgery it is inevitable to clamp the renal artery for some time, it is expected that reperfusion, following the removing of clamping, causes structural changes in the vessel wall which may result in a decrease in arterial function. In our model experiments on animals, the left renal arteries were atraumatically clamped for 30, 45 and 60 minutes. Simultaneously with clamping, perfusion regional renal venous cooling was applied to some of the animals, together with nephrotomy. In some cases cooling was performed in combination with antioxidant treatment. On the 3rd postoperative day renal arteries from both sides were removed, the right, intact ones serving as control. Noradrenaline dose effect curves characterizing vessel contractility were determined to demonstrate functional changes. It was established that cooling the renal artery for only 30 minutes was enough to rule out the damage due to ischaemia-reperfusion. If clamping lasted for 45 minutes, venous cooling of the kidney in combination with antioxidant treatment was necessary to spare arterial function. Clamping for 60 minutes resulted in irreversible/permanent decrease in contractility even if hypothermia and antioxidant treatment were given simultaneously.

Animals↗
PubMed1996

Combined low dose dipyridamole-dobutamine stress echocardiography to identify myocardial viability.

OBJECTIVES: We sought to evaluate the effects of combined administration of infra-low dose dipyridamole and low dose dobutamine on assessment of myocardial viability. BACKGROUND: Low dose pharmacologic stress echocardiography with either dobutamine or dipyridamole infusion has been proposed for the recognition of myocardial viability. METHODS: Thirty-four patients with rest wall motion dyssynergy by two-dimensional echocardiography and with angiographically proved coronary artery disease underwent in combination with two-dimensional echocardiographic monitoring: 1) low dose (5 to 10 microgram/kg per min over 3 min) dobutamine infusion; 2) infra-low dose (0.28 mg/kg over 4 min) dipyridamole infusion; 3) combination of infra-low dose dipyridamole infusion immediately followed by low dose dobutamine infusion (combined dipyridamole-dobutamine). RESULTS: Follow-up rest echocardiography was available in 30 patients. After revascularization, 82 segments showed a contractile improvement of > or = 1 grade, whereas 63 segments remained unchanged. The sensitivity of dobutamine, dipyridamole and combined dipyridamole-dobutamine for predicting recovery was 72% (95% confidence interval [CI] 60.9% to 81.3%), 67% (CI 55.8% to 77%) and 94% (CI 86.3% to 97.9%), respectively. The specificity of dipyridamole, dobutamine and combined dipyridamole-dobutamine was 95% (CI 86.7% to 99%), 92% (CI 82.4% to 97.3%) and 89% (CI 78.4% to 95.4%), respectively. The accuracy of the dobutamine, dipyridamole and combined dipyridamole-dobutamine test was 80%, 79% and 92%, respectively (combined dipyridamole-dobutamine vs. dobutamine, p < 0.05; combined dipyridamole-dobutamine vs. dipyridamole, p < 0.01). CONCLUSIONS: Infra-low dose dipyridamole added to low dose dobutamine recruits an inotropic reserve in asynergic segments that were nonresponders after either dobutamine or dipyridamole alone and destined to recover after revascularization.

Adult↗
PubMed1996

Does stress echocardiography predict the site of future myocardial infarction? A large-scale multicenter study. EPIC (Echo Persantine International Cooperative) and EDIC (Echo Dobutamine International Cooperative) study groups.

OBJECTIVES: We sought to assess whether the site of future myocardial infarction can be predicted on the basis of induced dyssynergy ("area at risk") recognized by stress echocardiography. BACKGROUND: The severity and extent of stress-induced dyssynergy are strong predictors of subsequent major cardiac events. However, high grade stenotic lesions are not strictly associated with the site of future coronary occlusions. METHODS: From the stress echocardiography multicenter trials data bank, we selected 70 patients (56 men; mean age +/- SD 58 +/- 11 years) meeting the following inclusion criteria: 1) dipyridamole (n = 53) or dobutamine (n = 17) stress echocardiography; 2) a spontaneously occurring infarction, with no intercurrent revascularization procedure between the initial study and the infarction; and 3) a follow-up rest echocardiogram obtained 41 +/- 90 days after the infarction. RESULTS: A complete ischemia-infarction mismatch (infarct-related dysfunction in a patient with negative stress test results) occurred in 29 patients (41%). A partial mismatch (ischemic dysfunction in a territory different from the infarct area) occurred in nine patients (13%). A match (ischemia-related and infarction-related dyssynergy involving the same region) occurred in 32 patients (46%). The average time interval between the stress examination and the occurrence of infarction or reinfarction was 144 +/- 160 days in patients with a match and 439 +/- 622 days in patients with a mismatch (p < 0.05). CONCLUSIONS: Induced ischemia (imaged as transient dyssynergy by pharmacologic stress echocardiography) inconsistently identifies the site of future infarction. The majority of spontaneous coronary occlusions leading to infarction are unheralded by induced ischemia. However, most infarctions occurring within 1 year of stress testing are in the area identified as ischemic during testing.

Databases, Factual↗
PubMed1996

Cyclic variation in myocardial gray level as a marker of viability in man. A videodensitometric study.

Experimental and human studies have shown that a preserved cyclic (diastolic-to-systolic) echoreflectivity variation, assessed by radiofrequency sampling of backscatter signal with non-commercially available prototypes, identifies viability in a myocardial segment with a resting dyssynergy. The objective of this study was to assess whether a videodensitometric analysis of myocardial gray level variation during cardiac cycle might identify viable but dyssynergic myocardium in a clinical setting. Thirty-four patients with a resting dyssynergy (akinesis in 26, marked hypokinesis in eight) in the septum and/or inferno-posterior wall were evaluated by videodensitometry. All echo studies were performed with commercially available instruments in the long axis parasternal view, with quantitative analysis of gray levels performed off-line on digitized images. Segmental wall motion was assessed with a 16 segment model of the left ventricle, each scored from 1, normal, to 4, dyskinetic. A follow-up echo study was obtained in all patients > 4 weeks after successful revascularization (in 22 by angioplasty, in 12 by bypass surgery). Two groups of segments were identified: 18 viable segments (contractile improvement of 1 grade or more in resting function after revascularization); 16 necrotic segments (no contractile improvement in resting function after revascularization). The % cyclic variation was higher in viable vs necrotic segments (26 +/- 16 vs 1 +/- 13%, P < 0.01), in spite of similar % systolic thickening (5 +/- 5 vs 4 +/- 6%, P = ns) and end-diastolic thickness (10 +/- 2 vs 10 +/- 2 mm, P = ns). When individual patient analysis was performed, % cyclic variation was below the 95% confidence limits obtained from normal control regions (n = 34; % cyclic variation = 38 +/- 14) in two out of 18 viable and in 14 out of 16 necrotic segments. A cut-off of > or = 9.4% cyclic variations in a dyssynergic segment yielded 89% sensitivity and 88% specificity for predicting functional recovery following successful revascularization. In conclusion, viable dyssynergic myocardial segments show a cyclic gray level variation at rest, which can be detected by simple videodensitometric analysis, much less technologically demanding than radiofrequency backscatter evaluation.

Cell Survival↗
PubMed1996

Infra-low dose dipyridamole test. A novel dose regimen for selective assessment of myocardial viability by vasodilator stress echocardiography.

Low (0.56 mg.kg-1 over 4 min) and high (0.84 mg.kg-1 over 10 min) doses of dipyridamole can identify viable myocardium through the contractile recovery of basally dyssynergic regions; however, it also induces ischaemia in susceptible patients. The aim of this study was to assess the potential of an "infra-low' dose of dipyridamole to selectively identify myocardial viability, independently evaluated by low dose dobutamine. Forty patients with resting dyssynergy and angiographically assessed coronary artery disease (1-vessel in 18, 2-vessel in 12, and 3-vessel in 10 patients) separately underwent a low dose dobutamine (5-10 micrograms.kg-1.min-1 for 3 min) echo test and an infralow dose (0.28 mg.kg-1 over 4 min) dipyridamole echo test. Systolic blood pressure (rest: 131 +/- 19 mmHg) changed slightly after dobutamine (137 +/- 21, P < 0.05 vs rest) and remained stable after dipyridamole (130 +/- 17, P = ns vs rest). Heart rate (rest: 68 +/- 13 beats.min-1) was also unchanged after dipyridamole (69 +/- 12, P = ns vs rest) and increased slightly after dobutamine (71 +/- 15, P < 0.05 vs rest and vs dipyridamole). No patient developed echocardiographic or electrocardiographic signs of ischaemia after either dipyridamole or dobutamine. Of the 243 segments with baseline dyssynergy, 70 were responders (i.e. they showed an improvement of 1 grade or more, from 1 = normal/hyperkinetic to 4 = dyskinetic in a 16-segment model of the left ventricle) by both dipyridamole and dobutamine, 157 were non-responders (i.e. they showed no change) by both dipyridamole and dobutamine, and 16 showed discordant results (five responders by dipyridamole only; 11 by dobutamine only). The overall concordance of dipyridamole and dobutamine was 93%. An echocardiographic follow-up could be obtained > 6 weeks after successful revascularization (achieved with angioplasty in 17, with by pass surgery in 3) in 19 patients and showed an improvement of one grade or more in 50 segments (viable) and no improvement in 50 segments (necrotic). The sensitivity of dobutamine and dipyridamole for predicting recovery was 76 and 78% respectively (P = ns); the specificity of both tests was 94%. In conclusion, infra-low dose dipyridamole is a haemodynamically neutral stress test which does not affect either heart rate or systolic blood pressure; it allows myocardial viability to be explored selectively, without eliciting ischaemia; it shows excellent overall concordance with low dose dobutamine and has good sensitivity and excellent specificity for predicting functional recovery following successful revascularization.

Adult↗
PubMed1995

[15-year echocardiographic follow-up of acromegalic patients].

An echocardiographic follow-up of 25 patients (pts) was performed, after the first examinations in 1978-1979. 15 pts have died in the last 15 years (Group 1), while 10 still living (Group 2). In Group 1 either the impaired global left ventricular at the time of the first echocardiography predicted a high mortality i.e. there were only two pts with normal echocardiographic findings. The other 6 acromegalic pts with a "normal heart" have survived. The left ventricular hypertrophy of pts in Group 2 was observed to increase during the 15-year follow-up, because of the development of systemic hypertension. In conclusion, the echocardiographic findings are of a good predictive value in estimations of the survival rate in acromegalic pts.

Acromegaly↗