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A Laczkovics

Publications and source records attributed to A Laczkovics.

At least 19 recordsLinked to original sources
PubMed1997

[Heart rupture after mitral valve replacement. Pathologic-anatomic findings].

The rupture of the free left ventricular wall is considered a serious complication following mitral valve replacement. We report about 3 cases characterized by similar pathologic-anatomical findings within the region of the left ventricle after mitral valve replacement. Following resection of the original and pathologically altered mitral valve and implantation of a prosthesis, rupture of the left ventricular wall occurred in short time intervals ranging from 1 to 12 h postoperatively. All cases represented a transverse midventricular disruption located between the mitral valve anulus and the resected papillary muscles. The histologic findings included necrotic, damaged myocardial structures with considerable bleeding to the interstitium. Inflammatory infiltration could be detected within the myocardial defects. Abnormal pathologic findings of the coronary arteries or intraoperative lesions could be excluded by thorough autoptic studies. Because of central localization of the ventricular disruption between the mitral valve anulus and the papillary muscles a direct traumatic myocardial injury caused by mitral valve orotheses is to be excluded. When taking into account several reports from literature in combination with our described findings, in autopsy, a loss of contractile integrity of the left ventricle following resection of mitral valve apparatus, especially the chordae tendinaea, should be considered as primary cause for this type of ventricular rupture. This destabilization will lead to a regionally stressec myocardial "stretching" which finally results in rupture of the left ventricular free wall. The described pathogenetic concept seemingly represents the decisive mechanism of this transverse midventricular disruption in all 3 cases. To prevent such post-operative complications, only very limited resection of the mitral valve apparatus should be performed to maintain parts of the chordae tendineae.

Aged↗
PubMed1994

Cardioprotection by nifedipine cardioplegia during coronary artery surgery.

In a double-blind, placebo-controlled, randomized clinical study, the cardioprotective effect of nifedipine (Adalat, Bayer) as an adjunct to St. Thomas' cardioplegia was investigated in 24 patients undergoing coronary artery bypass grafting. Nifedipine at a dosage of 200 micrograms or placebo was added to each 1000 ml of St. Thomas solution, under strict light protection. ECG and haemodynamic data, including cardiac output measurements, serum calcium levels, creatine phosphokinase, (CK) CK-MB and lactate were measured during and after the operation. Additional cardioprotective effects were demonstrated in the nifedipine group by a significantly lesser reduction of the cardiac index after cardiopulmonary bypass and lower post-operative CK and CK-MB serum levels (P < 0.05). The incidence of ischaemia and cardiac arrhythmias was significantly higher in the placebo group on the post-operative ECG.

Arrhythmias, Cardiac↗
PubMed1993

Relief of diastolic cardiac dysfunction after cyclosporine withdrawal in a cardiac transplant recipient.

Severe heart failure developed in a 49-year-old patient 18 months after orthotopic cardiac transplantation. Acute rejection as well as other overt causes of graft failure were excluded. Haemodynamic measurements suggested severe diastolic myocardial dysfunction. Since no other causes of diastolic heart failure were identified, a potential side effect from cyclosporine was considered. Cyclosporine was therefore withdrawn and immunosuppressive treatment was switched to conventional therapy consisting of azathioprine and prednisolone. Withdrawal of cyclosporine was followed by an impressive clinical improvement and by complete haemodynamic normalization. Therefore, in cases of otherwise unexplained graft failure, a potentially reversible side effect from cyclosporine should be taken into consideration.

Coronary Disease↗
PubMed1993

Exercise chronotropy in patients with normal and impaired sinus node function after cardiac transplantation.

The chronotropic response during graded, symptom limited exercise was investigated in 32 cardiac transplant recipients a mean of 49 +/- 18 days after transplantation. All patients had systematic evaluation of postoperative donor sinus node (SN) function and the cardioacceleratory response was compared according to the SN function. Twenty-one patients had normal postoperative SN studies (corrected SN recovery time < 520 msec, group I) while the SN function was impaired postoperatively in the remainder (n = 11, group II; corrected SN recovery time 4,149 +/- 6,283 msec in 5 patients, junctional escape rhythm in 6 patients). All patients had regained sinus rhythm at time of the exercise test. Patients in group II had lower basal sinus rates at the beginning of exercise (91.5 +/- 11 vs 101.4 +/- 7 beats/min, P < 0.02). This lower chronotropy was maintained over every incremental step (F rate between groups = 30, P = 0.0001, F rate vs workload = 15, P = 0.0001 by two-way ANOVA) and resulted in a significantly lower heart rate at individual peak exercise (108.3 +/- 20 vs 124.2 +/- 13 beats/min, P < 0.02). A total of 14/16 patients in group I but only 2/16 patients in group II accomplished a peak heart rate > or = 120 beats/min (P = 0.009). The workload achieved did not differ between the groups (107 +/- 29 vs 102 +/- 32 watts, P > 0.5). These data show a lower SN chronotropy during rest and at peak exercise in cardiac transplant recipients with postoperative SN deficiency and apparent normalization of SN function.

Adult↗
PubMed1993

Normal AV node function in patients with sinus node dysfunction after cardiac transplantation.

Postoperative atrioventricular nodal (AVN) function was compared in 55 patients with normal and 50 patients with impaired sinus node (SN) function after cardiac transplantation (corrected SN recovery time > 520 msec or sinus arrest +/- escape rhythm). Fifty-two patients had fixed atrial pacing at cycle lengths between 600 and 430 msec, and 53 patients at cycle lengths from 600 to 300 msec between postoperative weeks 1 to 3. Relative (stimulus-R interval; AVNRRP) and effective AVN refractory period (AVNERP) were determined in 53 patients at a cycle length of 500 msec. Only one of 105 recipients had high degree AVN conduction disturbance characterized by a Wenckebach phenomenon at cycle length < 630 msec in the first postoperative week. Three patients with normal and two patients with impaired SN function had Wenckebach cycle lengths > 430 msec while the Wenckebach cycle lengths were < or = 430 msec in the remainder (p = NS). Resting PQ interval (146 +/- 18 vs 162 +/- 32; p = 0.09), Wenckebach cycle length (350 +/- 53 vs 362 +/- 50 msec), AVNRRP (356 +/- 38 vs 367 +/- 37 msec), and AVNERP (217 +/- 48 vs 244 +/- 49 msec) did not differ significantly between patients with normal and impaired SN function. AVN conduction did not deteriorate during 318 +/- 130 days of follow-up (PQ at follow-up 154 +/- 17 and 158 +/- 22 msec, patients with normal and impaired SN function, respectively). One DDD pacemaker was placed for AVN conduction disturbance while 22 pacemakers were implanted for SN deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Long-term intrinsic pacemaker function in patients paced for sinus node deficiency after cardiac transplantation.

Fifteen cardiac transplant recipients requiring permanent pacing (AAI, n = 9; VVI, n = 6; rate responsive devices, n = 11) for postoperative sinus node (SN) insufficiency underwent evaluation of long-term SN function 240 to 1,461 days after transplantation. The intrinsic rhythm at the time of discharge was sinus in 7 patients; junctional escape in 6 patients; and pacemaker dependent in 2 patients. At follow-up, 5 patients had regained regular sinus rhythm, accounting for a total of 11 patients in sinus rhythm while 4 patients were in junctional bradycardia. The SN recovery time as determined by the permanent pacemaker was normal (< 1,500 msec) in only 1/8 patients in whom it was determined, although 4 of these 8 patients were temporarily overriding the pacemaker during ambulatory monitoring. Patients with pathological SN recovery times included 3 patients with late return of sinus rhythm and 4 patients who had recovered normal sinus rhythm before their discharge from the hospital. Three patients developed late symptoms despite apparent early normalization and underwent delayed pacemaker implantations on postoperative days 35, 52, and 225, respectively. We conclude that, in patients requiring pacemaker implantation after cardiac transplantation, normalization of SN function cannot be inferred from just return of sinus rhythm, regardless of whether it occurs early or late. These findings may have implications when a pacemaker exchange or explantation is being considered.

Electrocardiography↗
PubMed1992

Sinus node dysfunction after orthotopic cardiac transplantation: postoperative incidence and long-term implications.

We investigated incidence, normalization rates, and clinical significance of sinus node (SN) dysfunction after cardiac transplantation. Thirty-nine of 90 patients systematically evaluated presented with impaired SN function in the postoperative period. Of these, 22 normalized their SN function during follow-up while 17 remained impaired after 3 months. The proportion normalized was higher in patients with prolonged SN recovery time (11/16, 68.8%) and those reverting from escape rhythm to sinus rhythm until discharge (5/8, 62.5%) when compared to patients in escape rhythm throughout the postoperative period (5/11, 45.5%) or pacemaker dependence (1/4, 25%). There was no reliable postoperative predictor of normalization and necessity of long-term pacing. A postoperative heart rate consistently less than 70 beats/min (irrespective of the native rhythm) was significantly related to outcome (P = 0.01), but revealed unacceptable sensitivity (61.5%) and specificity (81%). After all, both patients with severe symptoms (near syncopes and syncope), were derived from this group. These two patients, who had been discharged in sinus rhythm, had late pacemakers implanted. An additional 17 patients had early pacemaker placement, only seven of which were constantly paced during follow-up. Given the low normalization rates, patients with postoperative escape rhythm are those most likely to benefit from pacemaker therapy over the long term. Even those in, or reverting back to, sinus rhythm until discharge may experience severe symptoms, particularly in the setting of a postoperative rate consistently less than 70 beats/min since this indicates a relatively lower probability of recovery.

Algorithms↗
PubMed1992

Influence of valve surgery on female fertility.

Pregnancies following cardiac valve surgery represent a considerable maternal and fetal risk. The present paper is a report of 163 women in child-bearing age who underwent cardiac valve surgery. Congenital (14.7%) and acquired (85.3%) cardiac defects required a total of 72 alloplastic and 16 bioprosthetic valve implantations. In 69 patients, purely instrumental correction was performed, in 6 patients conduits were placed. Thirty-four pregnancies were observed and led to the delivery of 18 healthy infants. The birth weight was always in the 2-sigma normal range or slightly above. Three cesarean sections were performed due to the cardiac defect, in 6 patients vacuum extraction or forceps delivery was done, and in 9 patients delivery was spontaneous. We observed 4 cases of spontaneous abortion, and in 12 cases interruption of pregnancy. 75.1% women never became pregnant. Potential risks in terms of endocarditis, repeated valve implantation and anticoagulation are emphasized, methods to decrease the physical strain during delivery are discussed.

Bioprosthesis↗
PubMed1992

Postoperative sinus node dysfunction in the transplanted heart. Impaired automaticity but normal refractoriness.

We describe the use of the extrastimulus technique to define the range of sinus node (SN) effective refractoriness (SNERP) in the denervated transplanted human heart. SNERP could be successfully determined in 18 of 28 patients corresponding to 25 of 43 SN studies and ranged from 210 to 360 ms at a basic pacing cycle length of 500 ms (95 percent confidence limits: 252.5 to 296.2 ms), which is shorter than reported in the innervated native heart. Sixteen data sets in 12 patients showed normal SN function and nine sets of measurements in seven patients showed abnormal SN function (corrected SN recovery time greater than 520 ms). While recovery time was profoundly abnormal (279.7 +/- 94 vs 7,284.8 +/- 10,454, p less than 0.001), the SNERP did not differ significantly between the groups (274.3 +/- 40 vs 286 +/- 42 ms at 500 ms, p = 0.5) and was normal at a range of 220 to 340 ms even in those patients with grossly impaired SN recovery (SNERP in patients with normal SN function: 210 to 360 ms at 500 ms). This study demonstrates that SN refractoriness in the transplanted human heart is shorter than previously reported in innervated controls and suggests that posttransplantation SN dysfunction is characterized by impaired automaticity rather than impaired refractoriness.

Adult↗
PubMed1992

[The coronary sinus as a source of activated T-lymphocytes in patients after orthotopic heart transplantation].

Mononuclear cells are the component of blood responsible for allograft recognition, rejection and acceptance. Shifts in the patterns of various mononuclear cell subpopulations were often used as a diagnostic tool in detection of heart rejection. The specificity of mononuclear cell monitoring has remained a controversial point until today, because infections led to similar changes as organ rejection. In this study we investigated whether mononuclear cells taken from coronary sinus blood give more information about the immunological status of the transplanted heart than those taken from central verous blood. After endomyocardial biopsy, coronary sinus blood was sampled by catheterization under X-ray control. Blood from the right atrium was taken for control measurement. Mononuclear cells obtained by density gradient cytocentrifugation were stained with monoclonal fluorescein conjugated antibodies detecting CD4- (T helper)-, CD8- (T suppressor)-, CD25- (Interleukin-2 receptor), and the CD71- (Transferrin receptor) antigens. Endomyocardial biopsies were graded according to the Billingham scheme. In the absence of rejection, the phenotypes of mononuclear cells from the coronary sinus did not differ from those of right atrial cells. Mild rejection led to a statistically insignificant increase of CD4- CD25- and CD7-antigen bearing cells in the coronary sinus blood, whereas the CD8 positive cells remained stable as compared to mononuclear cells from the right atrium. However, patients with moderate rejection showed a significant elevation of CD4 positive cells and activated T-cells (CD15-, CD71-positive cells) in the coronary sinus as compared with cells from the right atrium. The T helper/suppressor ratio (Th/s-ratio) shifted towards the T-helper population.(ABSTRACT TRUNCATED AT 250 WORDS)

CD4-CD8 Ratio↗
PubMed1992

The determinants of elevated total plasma cholesterol levels in cardiac transplant recipients administered low dose cyclosporine for immunosuppression.

Elevated total plasma cholesterol level is a frequent finding after cardiac transplantation. To identify risk factors for the development of hypercholesterolemic states, we applied multivariate statistics in a logistic and linear manner. Six-month posttransplantation levels of total plasma cholesterol in 57 adult heart recipients were available for analysis. Maintenance immunosuppression was carried out with either cyclosporine and azathioprine or both agents plus low-dose steroids. Total plasma cholesterol levels were dichotomized for the logistic analysis (1) by the age- and sex-matched 75th and 90th percentiles of a reference population according to National Institutes of Health treatment guidelines and (2) by the cut point 250 mg/dl. Twelve potential risk factors were evaluated as covariates: recipient age, body weight after 6 months, body weight gain over 6 months, body mass index after 6 months, body mass index gain over 6 months, current cyclosporine dosage, trough level of cyclosporine in whole blood according to high-performance liquid chromatography after 6 months, cumulative cyclosporine dosage over 6 months, serum bilirubin, type of original cardiac disease, maintenance steroids, and steroid bolus treatment. Multivariate logistic regression yielded the type of original cardiac disease as a significant predictor of posttransplantation hypercholesterolemia exceeding the 90th percentile (p = 0.019) and of hypercholesterolemia exceeding 250 mg/dl (p = 0.032). Maintenance steroids were identified as a second significant cofactor (p = 0.069) for total plasma cholesterol levels exceeding 250 mg/dl. Multiple linear regression again revealed the type of original cardiac disease and maintenance steroids as significant predictors by p values of 0.005 and 0.013, respectively. Patients with coronary artery disease as the original cardiac pathology and low-dose maintenance steroids had the greatest risk for the development of elevated total plasma cholesterol levels after cardiac transplantation. However, the overall predictive quality of the linear model was limited (multiple r value 0.43), which indicates that other variables besides the tested ones attributed to elevated total plasma cholesterol levels. These results confirm the adverse role of maintenance steroids on posttransplantation hypercholesterolemia and demonstrate the type of original cardiac disease as the most important risk factor. They suggest that abnormalities of lipoprotein metabolism and dietary factors continue to affect total plasma cholesterol levels after cardiac transplantation.

Adult↗
PubMed1991

A beat-by-beat analysis of electrocardiograms from cardiac transplant recipients.

A software system is described for producing a beat-by-beat analysis of the electrocardiograms from patients after heart transplantation. Pacemaker spikes are automatically detected and eliminated from the signals. R waves are located by a robust and accurate two-step algorithm. Based on the variable length of single heart beats, the Fourier coefficients of three orthogonal surface leads and of two intracardiac leads are calculated beat-by-beat. Power spectra are then obtained by combining contributions from the variable fundamental frequency and its multiples (harmonics) into fixed frequency classes of 1 Hz width and averaging over 60-120 cardiac cycles. Additionally, averaged beat-by-beat power spectra are calculated for windowed QRS complexes and T waves. As by-products, single beat quantities, such as R-R and R-T intervals, averaged signals for all leads, and the orientational autocorrelation function of the electrical vector of the heart, are obtained. Following beat-by-beat evaluation, mean values and standard deviations are obtained for all quantities.

Algorithms↗
PubMed1991

Transesophageal echocardiographic evaluation in mechanically assisted circulation.

Transesophageal echocardiography (TEE) has assumed an increasing importance in cardiothoracic surgery, but its use in patients with mechanically assisted circulation is unclear. We performed TEE in 11 patients: total artificial heart (TAH) 2, right ventricular assist device (RVAD) 2, left ventricular assist device (LVAD) 6, biventricular assist device (BVAD) 1. TEE was helpful in three areas. (1) selection of the assist device (AD): evaluation of left and right ventricular function allows differentiation of left, right or biventricular failure. (2) management of patient and optimization of pump performance: in all patients, correct cannula position and pump flow could be identified. Right ventricular failure in the presence of LVAD was found to cause hemodynamic instability in 4 patients. In 1 patient with repeated RV dilation and hypotension despite RVAD, TEE allowed optimal pump settings to be determined. (3) weaning from AD: Recovery of ventricular function can be assessed prior to weaning and repeatedly monitored during weaning. TEE in TAH is limited to problems such as identification of atrial thrombus or inflow valve dysfunction. We conclude that TEE is useful in the setting of mechanically assisted circulation for AD selection, improvement of patient management, optimization of pump performance and during weaning from AD.

Assisted Circulation↗
PubMed1991

Prosthetic bypass and flow reversal in the dissecting thoraco-abdominal aortic aneurysm.

In 1981 Carpentier and Co-workers introduced an alternative surgical procedure for great dissecting thoraco-abdominal aortic aneurysms, departing from the resection and the orthotopic implantation of a prosthesis (graft inclusion technique). Compression of the aneurysmatic false lumen from the inside under stepwise thrombosis of the aneurysmal sac with conservation of the main arterial origins was achieved by prosthetic bypass of the diseased vascular part and a flow reversal in the dissected aortic region by an oblique suture across the aortic lumen after the origin of the left subclavian artery. This procedure, distinguished by rather little effort and few complications (bleeding, ischaemic spinal cord damage) is described for all stages of dissecting thoracal aortic aneurysms. In the last 2 years this operation was performed in our department on 4 patients (1 m. 3 f) suffering from an acute dissecting thoraco-abdominal aortic aneurysm (Stanford type B). 2 patients died in the early postoperative period, one from a redissection close to the proximal anastomosis, the other due to the critical cardiac situation. 2 patients could be followed up postoperatively 10 and 27 months. In both cases no signs of minor perfusion of the spinal cord, the kidneys, or the mesenterial organs were observed. In both cases a partial thrombosis of the aneurysmal sac with intact blood stream to the major vessels in these regions could be demonstrated by sonography, angiography or DSA, and computer tomography. The concept of flow reversal proved to be an alternative to major resection procedures.

Aged↗
PubMed1991

Early results with the anatomical correction of transposition of the great arteries.

From November 1984 to April 1991, 38 children underwent an arterial switch operation for transposition of the great arteries (TGA). In 24 infants (mean age 8 days) TGA with intact ventricular septum was present, in 14 patients (mean age 75 days) TGA was combined with a ventricular septal defect (VSD). There were 11 in-hospital deaths with an overall mortality of 29%, mainly due to technical problems. Whereas the group TGA + VSD showed a mortality rate of 50%, simple TGA and the subgroup simple TGA younger than 14 days had a mortality rate of 16.7% and 17.4%, respectively. Mortality was not influenced by coronary artery morphology and age. In simple TGA, the data presented suggest that this operation can be performed with good short-term clinical results. Most children are asymptomatic and without medication at a mean follow-up time of 2.5 years; but as there are pathological postoperative findings in echocardiography, the long-term benefit remains a matter of concern. Considerable perioperative problems are present in cases of TGA + VSD so surgical management is more differentiated, including other options.

Follow-Up Studies↗
PubMed1991

[Significance of surgically corrected heart valve diseases on fertility].

We report on 111 patients, who were operated for heart valve failure. The influence of the operation on fertility was examined. Only 24 women became pregnant. From 34 pregnancies, 4 resulted in early abortion; in 12 cases abortion was performed (8 times for medical reasons), therefore 18 children were born. The remaining 87 operated patients (78.4%) never became pregnant, although only 29 patients were advised against pregnancy. 27 patients decided on various contraceptive methods by themselves.

Abortion, Induced↗