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P Pruszczyk

Publications and source records attributed to P Pruszczyk.

33 records · Page 2Linked to original sources
PubMed1995

Heart rate variability in pheochromocytoma.

The results of our study show that parasympathetic tone was higher in patients with pheochromocytoma than in patients with primary hypertension. An unusual spectral form of vagal activity was seen during excessive beta-adrenergic stimulation, while persistent hypertension with an excessive alpha-adrenergic stimulation was responsible for low cardiac sympathetic tone, probably due to desensitization of beta-adrenergic receptors.

Adrenal Gland Neoplasms↗
PubMed1995

Transoesophageal echocardiography for definitive diagnosis of haemodynamically significant pulmonary embolism.

Transesophageal echocardiographic evaluation of right and left pulmonary arteries, up to the origin of their lobar branches, was prospectively performed with a single plane probe in 32 consecutive patients (18 M, 14 F, aged 55.5 +/- 14.6, from 32 to 80 years) with clinical or echocardiographic suspicion of pulmonary embolism, who met transthoracic echocardiographic criteria of right ventricular overload. Transoesophageal echocardiography showed unequivocal (20 patients) or suspected (three patients) intraluminar thrombi in 88.5% of 26 patients with haemodynamically significant acute or chronic pulmonary embolism, confirmed with reference methods. The sensitivity of the unequivocal transoesophageal echocardiographic diagnosis was 80% for acute and 73% for chronic haemodynamically significant pulmonary embolism. No false-positive results were found (specificity 100%). Additionally, in three cases, transoesophageal echocardiography disclosed the cause of the right ventricular overload revealing a previously undiagnosed atrial septal defect or Ebstein anomaly. Direct visualization of proximal pulmonary arterial thrombi by transoesophageal echocardiography emerges as a useful new method of prompt and definite diagnosis of haemodynamically important pulmonary embolism.

Adult↗
PubMed1995

Plasma neuropeptide Y and catecholamines in women and men with essential hypertension.

Neuropeptide-Y (NPY) is a peptide proposed to modulate the effect of the sympathetic nervous system on blood pressure control and contribute to the development of essential hypertension. To assess the possible influence of gender on its role, we evaluated plasma NPY, noradrenaline (NA) and adrenaline (A) concentrations in men and women with essential hypertension. No difference in NPY concentration was found between genders, but NPY concentration was elevated in both hypertensive men and women. NA levels were similar in all investigated hyper- and normotensives, while A was increased only in hypertensive men. These results suggest various patterns of sympatho-adrenal activity in gender subgroups of patients with essential hypertension.

Adult↗
PubMed1995

Plasma neuropeptide Y during dynamic exercise in patients with essential hypertension.

UNLABELLED: The aim or the study was to assess plasma neuropeptide Y immunoreactivity concentration (NPY-ir) during dynamic exercise in pts with different stages of essential hypertension (ESH). We studied 25 males aged 29.4 +/- 6.3 yrs with established ESH (ESH) and 12 healthy males aged 27.3 +/- 5.1 yrs (C). Plasma concentrations of NPY-ir, NA, A, BP were measured before treadmill test, in the last minute of two six-min. work loads corresponding to 60% and 80% of maximal individual load and 30 min. after cessation of exercise. Plasma NPY-ir was evaluated with RIA, NA and A with REA. Gradual exercise resulted in an increase of NPY-ir in ESH (from 14.4 +/- 5.8 to 18.1 +/- 6.4 and 20.7 +/- 8.1 fmol/ml p = 0.036, p = 0.02) and in C (from 11.7 +/- 4.6 to 13.4 +/- 5.0 and 15.2 +/- 5.9 fmol/ml, p < 0.01). Likewise plasma NA and A increased in both groups. Plasma NPY-ir during exercise was significantly higher in ESH than in C (p = 0.041 and p = 0.047) while no such differences were observed in plasma NA and A. According to the left ventricle mass index (LVMI) ESH was divided into two subgroups: with left ventricular hypertrophy (LVH+) n = 10, LVMI = 159.7 +/- 7.7 g/m2 and without the hypertrophy (LVH-) n = 15 LVMI = 112.3 +/- 19.2g/m2. LVH- presented significant increase in plasma NPY-ir during exercise (from 14.7 +/- 5.7 to 18.2 +/- 6.5, 22.8 +/- 8.3 fmol/ml p < 0.01), while no changes in LVH+ were observed (from 14.1 +/- 5.8 to 17.8 +/- 6.0 and 17.8 +/- 6.7 fmol/ml, ns). LVH+ were older than LVH- (33.4 +/- 7.1 yrs vs 26.7 +/- 4.2 p = 0.04), but no correlation between age and plasma NPY-ir was noticed. No differences in plasma NA and A were present between these subgroups. CONCLUSION: Patients at different stages of essential hypertension display various patterns of sympatho-adrenal activation during dynamic exercise.

Adult↗
PubMed1995

Influence of alpha-adrenergic blockade on ventricular arrhythmias, QTc interval and heart rate variability in phaeochromocytoma.

There are strong experimental evidences that alpha 1-adrenergic stimulation significantly influences cardiac arrhythmogenesis, especially during myocardial ischaemia and reperfusion. However, anti-arrhythmic effects of alpha-blockade in humans were scarcely utilised. Thus the purpose of our study was to assess these effects in patients with phaeochromocytoma. In 22 patients simultaneous 24 h ECG and blood pressure (BP) monitoring, as well as estimation of the urinary 24 h free catecholamine excretion, were performed twice: before and during the treatment with the non-selective alpha-blocker, phenoxybenzamine. The heart rate variability was measured during four 5 min periods, at 10.00, 16.00, 22.00 and 04.00. During alpha-blockade systolic blood pressure (SBP) decreased from 137.6 +/- 23.8 to 126.5 +/- 15.7 mm Hg (P < 0.01), heart rate increased from 83.0 +/- 9.9 to 88.5 +/- 10.0/min (P < 0.02) and duration of QTc interval unsignificantly increased. Incidence of frequent or repetitive ventricular arrhythmias was significantly higher before treatment (in 9 vs 3 of 22 patients, P < 0.05). Heart rate variability significantly decreased during the treatment, with regard to all parameters, representing both the sympathetic and parasympathetic activity. We conclude that non-selective alpha-blockade significantly decreases the incidence of frequent or repetitive ventricular arrhythmias in patients with phaeochromocytoma, although the lack of QTc interval shortening suggests that the effect of class I drugs may participate in the anti-arrhythmic effects of phenoxybenzamine. Moreover, non-selective alpha-blockade in phaeochromocytoma significantly diminishes vagal activity.

Adrenal Gland Neoplasms↗
PubMed1994

[Detection of patent foramen ovale by transcranial Doppler ultrasonography].

This study compares the value of transcranial Doppler ultrasound (TCD) and transesophageal echocardiography (TEE) for detecting a patent foramen ovale (PFO). A total of 61 stroke patients under 65 years of age, were studied. A PFO was detected by TEE in 27 of 61 patients and these results were used as the gold standard. TCD confirmed the presence of PFO in 23 of the 27 patients and detected a PFO in a further 5 patients with normal TEE results. TCD had a sensitivity of 85% (23 of 27) and accuracy of 85% (52 of 61). The prevalence of PFO detected by both methods was 38%.

Cerebrovascular Disorders↗
PubMed1991

Long term follow-up after surgical removal of pheochromocytoma--observations in 61 patients.

89 patients were operated on for pheochromocytoma. 61 patients (37 women and 24 men) were available for extended follow-up. The final survey, performed 79.1 +/- 66.9 months postoperatively, provided data on survival, blood pressure tumor recurrence, malignant metastatic lesions, cardiovascular complications and coexisting diseases. There were 4 deaths during the follow-up period, including 2 instances of malignant pheochromocytoma. Permanent normalization of blood pressure was achieved in 38 patients (62.3%). This hypotensive effect was noted in 79.2% of patients with preoperative paroxysmal hypertension and in 40.8% of those with sustained hypertension. Permanent or re-developing postoperative hypertension was noted in 23 (37.7%) patients. This includes 4 cases of malignant pheochromocytoma, 4 cases of recurrent benign pheochromocytoma and 15 cases of essential hypertension. Cardiovascular complications during follow-up were rare and concerned the patients with essential hypertension diagnosed postoperatively.

Adolescent↗
PubMedDate not supplied

Mitogenic effect of neuropeptide Y in rat vascular smooth muscle cells.

Neuropeptide Y (NPY) is a vasoconstrictor released with norepinephrine from perivascular sympathetic nerves. Since sympathetic nerves appear to play a role in vascular smooth muscle cell (SMC) hypertrophy, we studied the effects of NPY on proliferation of cultured rat aorta- and vena cava-derived SMC. Both cell types displayed high-affinity NPY binding sites with displacement characteristics of [Pro34]NPY > NPY(13-36) > NPY(18-36) in aorta and [Pro34]NPY = NPY(13-36) = NPY(18-36) in the vena cava. Incubation with NPY (50-1000 nM) for 48 h increased by up to twofold cell number and [3H]-thymidine incorporation in both cell types (aortic more sensitive to NPY than venous). Following incubation with NPY, the disappearance of NPY immunoreactivity (-IR) from media was markedly delayed in the presence of SMC, and cell content of NPY-IR increased in a dose-dependent manner, indicating that SMC either diminish degradation of the peptide (possibly by internalization) or secrete endogenous NPY (or both). Structure-activity relationship studies with NPY(18-36) indicated involvement of Y1 receptors in mitogenesis. Thus, NPY has a mitogenic effect (probably mediated by Y1 receptors) and, therefore, may be a sympathetic trophic factor involved in vascular hypertrophy.

Animals↗
PubMedDate not supplied

[Transcatheter closure of patent foramen ovale in patients after cryptogenic stroke].

Paradoxical embolism through a patent foramen (PFO) is a possible mechanism of ischaemic stroke in patients with cryptogenic stroke. Occlusion of PFO in such patients is considered by some authors as most effective in stroke prevention. We present our initial experience with transcatheter closure of PFO with the new self-expanding device--the Amplatzer PFO occluder in three young patients (age < 50 years). Each of them experienced at least one ischaemic stroke episode, without a left heart or carotid source and each had an interatrial communication with right-to-left shunting during Valsalva manoeuvre on echocardiography. The PFO's were closed completely without complications, under transoesophageal echo guidance in general anaesthesia. Complete closure was confirmed at one-month follow-up echocardiogram in each patient. No repeat cerebral accidents occurred at that time. The procedures were relatively easy and the clear presentation of the implant on TEE and fluoroscopy, made implantation fully controlled. The unique feature of the device is, that until release it can easily be retrieved, repositioned or removed. Transcatheter closure of PFO with the Amplatzer PFO occluder may become the new therapeutic option for patients with cryptogenic stroke and presumed paradoxical embolism.

Adult↗
PubMedDate not supplied

[Does hormonal activity of pheochromocytoma affect long-term prognosis in surgically treated patients?].

89 patients were operated upon for pheochromocytoma. 61 patients (37 women and 24 men) were available for follow-up. Mean age at operation was 39 +/- 12.3 yrs. Before operation paroxysmal and sustained hypertension were observed in 34 (55.7%) and 27 (44.3%) patients, respectively. Postoperatively permanent normalization of blood pressure was achieved in 38 cases (62.3%). All patients were divided into four groups. Group I with increased urine excretion of noradrenaline (NA) and adrenaline (A) consisted of 19 (31.1%) patients. Group II (increased NA excretion) included 27 (44.3%) patients. Group III comprised 3 (4.9%) cases with elevated A excretion. 12 (19.7%) patients with normal urinary excretion of catecholamines and increased excretion of methoxycatecholamines were alloted to group IV. Permanent normalization of blood pressure predominantly was observed in group IV--91.6%, whilst in group I, II and III this hypotensive effect was noted in 57.9%, 51.8% and 2/3, respectively. Permanent normalization of blood pressure can be mainly expected in patients with pheochromocytoma in whom catecholamines are rapidly inactivated within the tumor.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

[Evaluation of the usefulness of certain localization methods in diagnosis of pheochromocytoma].

Localization tests including TC-scans, scintigraphy with 131I-radiolabelled metaiodobenzylguanidine and ultrasound have been performed in 68 patients with diagnosed pheochromocytoma. Diagnosis was based on clinical symptoms and increased catecholamines and/or their metabolites excretion with the urine. Proper diagnosis with CT-scans was 97%, scintigraphy--92%, and ultrasound--93%; false negative results in scintigraphy amounted to 8% (3 patients) and 5% (3 patients) in case of ultrasound. CT-scans were free of such errors. False positive diagnosis was made in 2 (3%) patients with CT-scans and in 1 (2%) patient tested with ultrasound. These results suggest that pheochromocytoma may be precisely localized with non-invasive techniques, especially CT-scans.

Adolescent↗
PubMedDate not supplied

[Blood pressure in patients after unilateral adrenalectomy for aldosterone producing adrenal adenoma].

Forty five patients (35 women and 10 men) who underwent adrenalectomy for aldosterone-producing adrenal adenoma were followed up for 5.7 +/- 4.7 years (1-17 years). Stable normalization of blood pressure was noted in 27 (60%) patients. In 16 patients the primary hypertension and in 1 patient the second adrenal adenoma were diagnosed after surgery. Statistically significant decrease in daily excretion of adrenaline and noradrenaline with the urine, reduced adrenaline/noradrenaline ratio and reduced catecholamines and their metabolites ratio were noted in the operated patients in comparison to healthy volunteers indicating catecholamines metabolism disorders. Surgical treatment of adrenal adenoma besides normalization of blood pressure diminishes biochemical abnormalities. Development of the primary blood hypertension may be expected in some patients.

Adenoma↗
PubMedDate not supplied

Neuropeptide Y and alpha-adrenoceptor interactions in patients with essential hypertension.

Neuropeptide Y (NPY) is a vasoconstrictor sympathetic cotransmitter and a modulator of adrenergic function whose role in hypertension is yet unknown. We studied the co-release of NPY and noradrenaline (NA) in patients with essential hypertension (13 females, 11 males, age 42 +/- 13 years) by measuring plasma levels of NPY-immunoreactivity (-ir, radioimmunoassay) and NA (radioenzymatic method) following administration of clonidine (CL 300 micrograms, p.o.). At rest, only NPY-ir levels significantly correlated with diastolic blood pressure (DBP, r = 0.42, p < 0.05). Three hours after CL, there were a decrease in mean arterial pressure and plasma NA (by 31 +/- 14 mmHG, p < 0.05 and 92 +/- 10 pg/ml, p < 0.01) but no change in NPY-ir levels. Patients were subsequently subdivided into groups with high (> or = 90 mmHg) or normal DBP (< or = 89 mmHg) and with or without elevated plasma NA levels (above or below 414 pg/ml, a normotensive mean +1 standard deviation). In hypertensives, but not in those with normal DBP, plasma NPY-ir correlated not only with DBP but also with systolic and mean blood pressure (r = 0.53 and r = 0.60, respectively) at rest. Hypertensives with "high" NA had significantly lower resting plasma NPY-ir levels than those with "low" NA (7.1 +/- 3.6 vs 14.7 +/- 6.0 fmol/ml, p < 0.05). In the former group, CL evoked the greatest fall in plasma NA, and also decreased NPY-ir levels by 50% (p < 0.05). Thus, patients with essential hypertension were found to display differential patterns of changes in sympathetic cotransmitters to clonidine. NPY may contribute to the increased blood pressure in hypertensives and together with NA, mediate hypotensive action of clonidine but only in the hyperadrenergic subgroup of hypertensives.

Adult↗