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Zoltán Galajda

Publications and source records attributed to Zoltán Galajda.

9 recordsLinked to original sources

Rate of tension redevelopment is not modulated by sarcomere length in permeabilized human, murine, and porcine cardiomyocytes.

The increase in Ca(2+) sensitivity of isometric force development along with sarcomere length (SL) is considered as the basis of the Frank-Starling law of the heart, possibly involving the regulation of cross-bridge turnover kinetics. Therefore, the Ca(2+) dependencies of isometric force production and of the cross-bridge-sensitive rate constant of force redevelopment (k(tr)) were determined at different SLs (1.9 and 2.3 mum) in isolated human, murine, and porcine permeabilized cardiomyocytes. k(tr) was also determined in the presence of 10 mM inorganic phosphate (P(i)), which interfered with the force-generating cross-bridge transitions. The increases in Ca(2+) sensitivities of force with SL were very similar in human, murine, and porcine cardiomyocytes (DeltapCa(50): approximately 0.11). k(tr) was higher (P < 0.05) in mice than in humans or pigs at all Ca(2+) concentrations ([Ca(2+)]) [maximum k(tr) (k(tr,max)) at a SL of 1.9 mum and pCa 4.75: 1.33 +/- 0.11, 7.44 +/- 0.15, and 1.02 +/- 0.05 s(-1), in humans, mice, and pigs, respectively] but k(tr) did not depend on SL in any species. Moreover, when the k(tr) values for each species were expressed relative to their respective maxima, similar Ca(2+) dependencies were obtained. Ten millimolar P(i) decreased force to approximately 60-65% and left DeltapCa(50) unaltered in all three species. P(i) increased k(tr,max) by a factor of approximately 1.6 in humans and pigs and by a factor of approximately 3 in mice, independent of SL. In conclusion, species differences exert a major influence on k(tr), but SL does not appear to modulate the cross-bridge turnover rates in human, murine, and porcine hearts.

Adult↗

Hand perfusion with 99mTc-HSA in patients expecting to undergo coronary bypass surgery: elaboration of a new complex diagnostic protocol for the safe removal of a radial artery graft.

BACKGROUND: The Allen test is used worldwide for radial artery graft removal. The postoperative examination of our patients' hand function and circulation proved that beside the transient neurological complications chronic hand circulatory disorders may arise. AIM: To develop a non-invasive method suitable for an objective evaluation of the hand's circulation to make it possible to use radial arteries safely for the revascularization of coronary arteries. METHODS: We examined 35 patients. After selective compression of the radial and ulnar arteries of both hands, we injected 400 MBq (99m)Tc-HSA intravenously and acquired 240 images, each of 1 s. After 30 s we released the ulnar artery first, and after 120 s the radial artery, too. Then computer analysis was performed. RESULTS: The patients could be divided into two groups. In the majority of them, releasing only the ulnar artery resulted in a good circulation of the fingers. It meant that the time-activity curve rapidly reached its maximum, and the activity did not change even after releasing the radial artery. In a smaller proportion of the patients the activity of the fingers increased only slowly, and did not reach a plateau even after 30 s. Following the release of the radial artery a further increase in the activity could be observed. We assume that the latter patient group is at risk of consequent circulatory disorder of the fingers after the removal of the radial artery, whereas in the former group the artery could be removed safely. CONCLUSIONS: Hand perfusion with (99m)Tc-HSA is useful in patients selected for coronary bypass operations, so we recommend the introduction of this method as a routine examination before the removal of the radial artery in patients with an abnormal Allen test.

Adult↗

The Allen test.

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Angiography↗

[Ebstein's anomaly--experiences with surgical treatment in adulthood].

INTRODUCTION: Long time results with operative treatment of Ebstein anomaly were examined. PATIENTS AND METHODS: From January 1985 to March 2001 16 patients with Ebstein anomaly were operated on. Ages ranged from 16 to 49 years at the time of operation. In 7 cases tricuspid valve repair was possible, and in 9 cases prosthetic valve was inserted. In all but one biological prosthesis has been used. In 15 cases atrial septal defect occurred as a concomitant anomaly, which was closed by direct suture in 9 cases and with patch (2 Dacron, 4 pericardium) in 6 cases. RESULTS: There was no early death (30 days postoperatively). 1 patient following tricuspid repair was reoperated on at the 9th postoperative day because of significant tricuspid insufficiency. Tricuspid valve replacement was performed with a biological prostheses. There were 3 late deaths: 2 patients (12.5%) in the first postoperative year (1 cardiac cause, 1 unknown), 1 patient died 6 years postoperatively following reoperation. There were 3 more patients requiring reoperation (total reoperation rate 28.6%) one of them a few days after the primary operation and two others 9 and 11 years following the first operation. 13 patients were recalled to control investigations. The authors could not contact 2 patients, 1 patient living abroad could not appear at our clinic. 10 patients have been investigated 6 months to 16 years after the operation. There were 9 patients in New York Heart Association class I or II. 2 patients had their own repaired valve; both had tricuspid insufficiency grade III. Both were completely active. 8 patients had previously tricuspid valve replacement and good valve function, but six of them have not been working any more. There were 5 female patients under 35 at the time of operation and 2 of them had successful pregnancies. CONCLUSIONS: Patients with Ebstein anomaly in NYHA stage III-IV. can be successfully treated surgically.

Adolescent↗

[Two years experience with the Pericarbon stentless valve in Hungary].

OBJECTIVE: In 1999 stentless heart valves were introduced for treatment of the aortic valve disease in elderly patients at the Department of Cardiac Surgery of the University of Debrecen. PATIENTS, METHODS: Between December 1999 and November 2001 63 patients underwent aortic valve replacement with Sorin Pericarbon stentless valve. The mean gradient was 80 +/- 11 mmHg, the left ventricular wall thickness was 15.5 +/- 0.7 mm and the ejection fraction was 54 +/- 8% preoperatively. 4 patients were in NYHA II, 47 in NYHA III and 12 in NYHA IV functional class. 42 patients had isolated aortic valve replacement, the remaining 21 patients underwent combined surgical procedure. The aortic x-clamp and perfusion times were 125 +/- 27 and 153 +/- 48 minutes respectively. Nine 21 mm, twenty-three 23 mm, seventeen 25 mm, twelve 27 mm and two 29 mm valves were implanted. RESULTS: The hospital mortality was 6% (four patients). Transient atrial fibrillation was the most frequent postoperative complication. 77% of the patients had uneventful recovery and left hospital one week after surgery. Transthoracic echocardiography was performed at all patients before discharge and in December 2001. The mean follow up time was 9.7 +/- 5.8 months. 86% of the patients were in NYHA I functional class at the time of the follow up. The mean and peak transvalvular gradients were 9.4 +/- 4.1 mmHg and 16.1 +/- 6.8 mmHg respectively. The left ventricular wall thickness has decreased significantly (12.5 +/- 1.1 mm). CONCLUSION: The Sorin Pericarbon stentless valve is an easily implantable valve replacement device. Due to the excellent hemodynamic properties and the unnecessary anticoagulation it could be safely used in elderly patients.

Adult↗

Radiation-induced coronary artery disease in Hodgkin's disease.

PURPOSE: Secondary malignant tumours and cardiovascular complications are of great importance among the late complications after treatment for Hodgkin's disease (HD) because they may significantly reduce the patients' life expectancy. We report on coronary artery disease (CAD) after treatment for HD. METHODS AND MATERIALS: We present the case of two female patients with HD who received mediastinal irradiation after which complete remission was achieved. In 12 and 19 years after the onset of the disease, control examinations revealed ischaemic heart disease, which was confirmed by coronary arteriography and solved by stent implantation in one of the patients and bypass surgery in the other one. CONCLUSIONS: Ischaemic heart disease was due to early CAD, which was associated with mediastinal irradiation accompanied by hypothyroidism, hyperlipidaemia and, possibly, early menopause, all posing an increased risk for the cardiologic disease. Our cases may serve as a warning example to carefully plan the management (low dose, involved field irradiation) of newly diagnosed patients as well as the cardiologic follow-up of patients with HD.

Adult↗

Activation of the poly(ADP-ribose) polymerase pathway in human heart failure.

Poly(ADP-ribose) polymerase (PARP) activation has been implicated in the pathogenesis of acute and chronic myocardial dysfunction and heart failure. The goal of the present study was to investigate PARP activation in human heart failure, and to correlate PARP activation with various indices of apoptosis and oxidative and nitrosative stress in healthy (donor) and failing (NYHA class III-IV) human heart tissue samples. Higher levels of oxidized protein end-products were found in failing hearts compared with donor heart samples. On the other hand, no differences in tyrosine nitration (a marker of peroxynitrite generation) were detected. Activation of PARP was demonstrated in the failing hearts by an increased abundance of poly-ADP ribosylated proteins. Immunohistochemical analysis revealed that PARP activation was localized to the nucleus of the cardiomyocytes from the failing hearts. The expression of full-length PARP-1 was not significantly different in donor and failing hearts. The expression of caspase-9, in contrast, was significantly higher in the failing than in the donor hearts. Immunohistochemical analysis was used to detect the activation of mitochondrial apoptotic pathways. We found no significant translocation of apoptosis-inducing factor (AIF) into the nucleus. Overall, the current data provide evidence of oxidative stress and PARP activation in human heart failure. Interventional studies with antioxidants or PARP inhibitors are required to define the specific roles of these factors in the pathogenesis of human heart failure.

Adenosine Diphosphate Ribose↗