Tivadar Hüttl

Venous Myogenic Tone and Its Regulation Through K+ Channels Depends on Chronic Intravascular Pressure

In this study, we compared the level of myogenic tone and its negative-feedback control through specific K+ channels in two types of human veins (saphenous [SV] and cephalic [CV] veins), which experience different ranges of pressure in vivo. We also investigated whether an experimental model of increased venous pressure in rats exposed to head-up tilt for 2 weeks produced changes similar to those observed in the human veins. Cylindrical vein segments were cannulated, their diameters were measured, and the intraluminal pressure was set at different levels (2 to 30 mm Hg) in vitro. Acetylcholine test showed that during the regular harvesting process 76% of the human SVs exposed for coronary bypass grafts had no functional endothelium. We found significant myogenic tone in the human SV, where the in vivo pressure is high, but it was not present in the human CV, where the in vivo pressure is low. The nonspecific K+ channel antagonist, tetraethylammonium (TEA), decreased the diameter of the human SV but not the CV. Iberiotoxin and 4-aminopyridine, blockers of the Ca(2+)-sensitive (KCa) and voltage-gated K+ (KV) channels, also decreased the diameter of the human SV by 10.2 +/- 4.8% and 19.5 +/- 4.7%, respectively. In the rat SV, significant myogenic tone was found, but TEA had no effect, even after 2 weeks of in vivo pressure increase in the hindlimb by head-up tilt. We conclude that (1) an increased venous myogenic tone correlates with higher chronic intraluminal pressure loads, (2) KCa and KV channels counterregulate the myogenic tone in human, but not in rat, saphenous vein, (3) the counterregulatory effect is more effective at high than at low intraluminal in vitro pressure levels, and (4) its development is probably a long-term process.

Characterization of pericardial and plasma ghrelin levels in patients with ischemic and non-ischemic heart disease

Ghrelin is an endocrine regulatory peptide with multiple functions including cardioprotective effects. It is produced in various tissues among others in the myocardium. Pericardial fluid has been proven to be a biologically active compartment of the heart that communicates with the myocardial interstitium. Thus, pericardial level of certain agents may reflect their concentration in the myocardium well. In our study we measured acylated (active) and total (acylated and non-acylated) pericardial and plasma ghrelin levels of patients with ischemic and non-ischemic heart disease. Pericardial fluid and plasma samples were obtained from patients with coronary artery disease (ISCH, n=54) or valvular heart disease (VHD, n=41) undergoing cardiac surgery. Acylated pericardial ghrelin concentrations were found to be significantly higher in patients with ischemic heart disease (ISCH vs. VHD, 32±3 vs. 16±2pg/ml, p<0.01), whereas plasma levels of the peptide showed no difference between patient groups. Pericardial-to-plasma ratio, an index abolishing systemic effects on local ghrelin level was also significantly higher in ISCH group for both acylated and total ghrelin. Plasma total ghrelin showed negative correlation to BMI, plasma insulin and insulin resistance index HOMA-A. Pericardial acylated and total ghrelin concentrations were negatively correlated with posterior wall thickness (R=-0.31, p<0.05 and R=-0.35, p<0.01, respectively). Plasma insulin concentration and HOMA-A showed significant negative correlation with pericardial ghrelin levels. In conclusion, increased pericardial active ghrelin content and higher pericardial-to-plasma ghrelin ratio were found in ischemic heart disease as compared to non-ischemic patients suggesting an increased ghrelin production of the chronically ischemic myocardium. According to our results, pericardial ghrelin content is negatively influenced by left ventricular hypertrophy and insulin resistance.

Successful cardiac resynchronization therapy after heart transplantation.

We describe a case of a 56-year-old male patient, who developed refractory dilated cardiomyopathy 5 years after heart transplantation. An atriobiventricular pacemaker was implanted when indication criteria of cardiac resynchronization therapy (CRT) were seen. The intraventricular dyssynchrony was significant before CRT, while synchronous contraction was demonstrated later with the beneficial reverse remodelling of the left ventricle. Resynchronization therapy resulted in significant improvement of the patients clinical parameters. The success of this therapy points out the possible role of CRT in the treatment of chronic allograft failure after heart transplantation.

Acute Type A Aortic Dissection Complicated by Aortic Stent Graft Collapse

A 57-year-old man complaining of chest pain presented with signs of lower limb ischemia 1 year after implantation of a stent graft at the aortoiliac bifurcation. A computed tomography scan revealed the presence of a type A aortic dissection and complete collapse of the stent graft by bulging of the false lumen. The patient underwent emergency surgical reconstruction of the aortic root and arch, which allowed reexpansion of the previously collapsed stent graft. Stenting of residual stenoses distal to the stent graft and of an occluded left renal artery was also successful.

A simple surgical method for removing a large floating thrombus from the ascending aorta

We report the successful surgical removal of a large floating thrombus from the ascending aorta causing systemic embolization. It was diagnosed by transesophageal echocardiography (TEE), CT scan, aortography and Cardiovascular Magnetic Resonance Imaging (CMR). The free-floating, highly embolic source 2 cm distal to the left coronary sinus was removed from the ascending aorta using a simple surgical technique. Isolated cerebral perfusion with circulatory arrest on normothermia provided a simple and safe access to the thrombus attached to a ruptured atherosclerotic plaque. The patient was discharged on the 7 th postoperative day after an uneventful recovery.

Aortic coarctation reconstructed by resection and homograft replacement in the 1950s: long-term outcome 40 years after operation

Since the first successful repair of aortic coarctation by Dr Clarence Crafoord in 1945, there are few data regarding late follow-up of homografts in this position. Between 1957 and 1959, 7 patients underwent surgical correction of aortic coarctation by Professor József Kudász at the Department of Cardiovascular Surgery, Semmelweis University, using freeze-dried aortic homograft. We were able to locate 4 of these patients and found no significant complications due to the operation. We report on this 40-year follow-up of implanted aortic homograft.

Early complications and their treatment after heart transplantation in Hungary – experiences of the first 16 years

UNLABELLED Heart transplantation is the most successful current long-term therapy of end stage cardiac failure. AIM In order to improve the results of the Hungarian heart transplantation activity, all data from the first 16 years were retrospectively examined and matched with the relevant literature. METHODS Between January 1992 and December 2007, 127 heart transplantations were performed in 125 patients in Hungary. Above the documentation of the Department of Cardiovascular Surgery, Semmelweis University, the archives of the Institute of Forensic Medicine, Semmelweis University, the Registry of Hungarian National Blood Transfusion Service, Organ Coordination Office and the data of the Gottsegen György National Institute of Cardiology were used. RESULTS Early mortality has been approaching the international level recently. Graft failure was the primary cause of death in the Hungarian practice as well, followed by infection, uncontrollable bleeding during surgery and multiorgan failure. In one case successful acute retransplantation was performed, but the most effective, ventricular assist device therapy is completely missing from the armamentarium. Excellent results were achieved with medical treatment against acute rejection such as written in the international literature. CONCLUSIONS For the sake of developing, regular usage of assist device therapy in Hungary is a prominent task. Development and application of standard protocols providing better quality in organ donor treatment and donation management have to be pressed.

[Osteosynthesis with plates for full sternal dehiscence (Titanium Sternal Fixation System Synthes) -- first use in Hungary].

The prevalence of deep sternal infection after cardiac surgery is between 0,5 and 5%, with an average mortality up to 50%. The authors present the case of the rst sternal osteosynthesis carried out in Hungary after postoperative deep sternal infection. Using this orthopedic reconstructive surgical technique in this patient group, an anatomical reconstruction and reposition of the sternum is feasible. With the Titanium Sternal Fixation Synthes system reconstruction of total or partial sternal absence is possible.

Számítástechnikai döntéstámogató rendszer kiépítése a szívsebészetben: a 3D tervezéstől a posztoperatív eredményekig

INTRODUCTION Although surgical specialties utilize static models for preoperative planning, the evolution of dynamic planning methods and computer simulations created the opportunity for the introduction of dynamic parameters in cardiac surgery. Our aim was to apply 3D models in cardiac surgical practice, predicting fluid dynamic results, ventricular shape, volume and function before the operation. METHODS Using a script developed by us, the raw DICOM files were imported, the dilated left ventricle was modeled and fluid dynamic parameters were simulated, such as flow kinematic and profile analysis, turbulence calculation and myocardial response to shear stress. Then step-by-step simulation of the surgical ventricle restoration procedure was accomplished and the calculated variables were imbedded in silico model. The length of resection lines was modified based on the previous computer simulation and applied during the operation, if feasible. RESULTS The sphericity and conicity indexes were improved significantly in postoperative period (0.42 vs. 0.67 and 0.36 vs. 0.72, p < 0.05). The occurred shear stress at endocardium decreased 83% due to the normalization of flow kinematic pattern of the ventricle in postoperative period (132.21 ± 29.5 dyne/cm2 vs. 22.92 ± 10.3 p < 0.05 dyne/‌cm2). The postoperative turbulent flow pattern significantly decreased, according to our computational method (2712 vs. 1823, p < 0.0001). CONCLUSION With our method, the standardization of the surgical ventricle reconstruction was achievable and the surgical steps were predictable. Therefore, a new decision making support system was established in cardiac surgery for high risk patients. A personalized surgical technique was offered to our patients, improving their life expectancy and quality of life.INTRODUCTION Although surgical specialties utilize static models for preoperative planning, the evolution of dynamic planning methods and computer simulations created the opportunity for the introduction of dynamic parameters in cardiac surgery. Our aim was to apply 3D models in cardiac surgical practice, predicting fluid dynamic results, ventricular shape, volume and function before the operation. METHODS Using a script developed by us, the raw DICOM files were imported, the dilated left ventricle was modeled and fluid dynamic parameters were simulated, such as flow kinematic and profile analysis, turbulence calculation and myocardial response to shear stress. Then step-by-step simulation of the surgical ventricle restoration procedure was accomplished and the calculated variables were imbedded in silico model. The length of resection lines was modified based on the previous computer simulation and applied during the operation, if feasible. RESULTS The sphericity and conicity indexes were improved significantly in postoperative period (0.42 vs. 0.67 and 0.36 vs. 0.72, p < 0.05). The occurred shear stress at endocardium decreased 83% due to the normalization of flow kinematic pattern of the ventricle in postoperative period (132.21 ± 29.5 dyne/cm2 vs. 22.92 ± 10.3 p < 0.05 dyne/‌cm2). The postoperative turbulent flow pattern significantly decreased, according to our computational method (2712 vs. 1823, p < 0.0001). CONCLUSION With our method, the standardization of the surgical ventricle reconstruction was achievable and the surgical steps were predictable. Therefore, a new decision making support system was established in cardiac surgery for high risk patients. A personalized surgical technique was offered to our patients, improving their life expectancy and quality of life.

Migration of an epicardial pacemaker into the abdominal cavity

Migration of a permanent pacemaker generator from their intramuscular pocket to the abdominal cavity is a less frequent, but potentially life-threatening complication. The authors present the case of a 69-year-old woman, who visited the emergency department of the clinic, with complains of non-specific abdominal symptoms. Her past medical history included a complete atrioventricular block diagnosed in 2009 during the mitral valve replacement and since then she had an epicardial permanent pacemaker; the pulse generator was placed into an intramuscular pouch created in the left subcostal region. Surprisingly, radiologic examinations showed that the generator migrated into the pouch of Douglas. Considering patient safety, first a new intracardiac pacemaker was implanted and then the migrated device was removed surgically. The patient was discharged on the seventh postoperative day.Az epicardialis pacemakerek ritka, de akár életet veszélyeztető szövődménye a generátortelepnek a subcostalisan kialakított zsebből a hasüregbe történő elvándorlása. A szerzők 69 éves nőbetegük esetét ismertetik, aki aspecifi kus hasi panaszokkal jelentkezett a klinika sürgősségi osztályán. Anamnéziséből kiemelendő, hogy korábbi mitralisműbillentyű-műtétét követően kialakult III. fokú atrioventricularis blokkja miatt epigastrialis pacemakert helyeztek be úgy, hogy a pacemakergenerátort a subcostalisan kialakított intramuscularis zsebben helyezték el. Mellkasátvilágítás igazolta, hogy a telep – eredeti helyétől messzire – a Douglas-üregbe vándorolt. A szokatlan helyre és távolságra vándorolt készüléket hasi feltárásból távolították el, közvetlenül azt követően, hogy új endocardialis pacemakerrendszer került beültetésre. A beteg szövődménymentesen, a 7. posztoperatív napot követően otthonába távozott. Orv. Hetil., 2015, 156(4), 154–157.