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Martin Czerny

Publications and source records attributed to Martin Czerny.

14 recordsLinked to original sources
PubMed2003

Coronary reoperations: recurrence of angina and clinical outcome with and without cardiopulmonary bypass.

BACKGROUND: We compared our experience of minimal tissue dissection and target vessel revascularization without cardiopulmonary bypass (CPB) with the standard procedure of total dissection of the heart and complete revascularization with CPB in patients who had elective reoperative coronary artery bypass grafting (redo-CABG). METHODS: We analyzed recurrence of angina and clinical outcome in 118 patients who had elective redo-CABG between January 1995 and April 2002. Seventy-four patients had redo-CABG with CPB, and 44 patients had redo-CABG without CPB. RESULTS: Perioperative outcome was comparable with regard to morbidity and mortality rates. At follow-up, the mean Canadian Cardiovascular Society score was 1.3 +/- 0.6 in patients who had redo-CABG with CPB and 1.7 +/- 0.8 in patients who had redo-CABG without CPB (p = 0.02). At follow-up, patients who had redo-CABG without CPB had a higher rate of recurrence of angina (log rank = 0.001) and higher use of nitrates (p = 0.015). Target vessel revascularization was an independent predictor of recurrence of angina in younger patients (< 75 years; p = 0.012) but not in the elderly (> or = 75 years; p = 0.142). CONCLUSIONS: In elective redo-CABG patients, minimal tissue dissection and target vessel revascularization without cardiopulmonary bypass did not add significant benefit with regard to perioperative morbidity and mortality. The unsatisfactory relief of symptoms does not seem to justify target vessel revascularization by a less invasive approach. Therefore, this technique should be offered exclusively to patients at high risk with complete revascularization using CPB, such as the elderly.

Aged↗
PubMed2003

Neurocognitive deficit following mitral valve surgery.

OBJECTIVE: Neurocognitive deficit is an important complication in patients undergoing open heart surgery. The aim of this prospective, contemporary study was to objectively measure neurocognitive brain function following mechanical mitral valve replacement and mitral valve repair. METHODS: Forty consecutive, unselected patients (mechanical valve replacement n=20, mean age 65+/-14; valve repair n=20, mean age 64+/-7, P=0.896) entered this prospective, contemporary study. Neurocognitive function was objectively measured by means of P300 auditory evoked potentials (peak latencies, ms) and two standard psychometric tests (Mini Mental State Examination, Trailmaking Test A (TTA)), preoperatively, 7 days and 4 months postoperatively. RESULTS: Before operation, neurocognitive brain function was comparable in both patients groups (mechanical valve replacement versus valve repair: P300 potentials 374+/-25 versus 378+/-46 ms; P=0.791 and TTA 57+/-15 versus 54+/-10 s; P=0.552). Following mechanical valve replacement, neurocognitive function continuously worsened (7 day-follow-up: P300 potentials 392+/-28, P=0.001 versus preop and TTA 65+/-17, P=0.0001; 4-month follow-up: P300 potentials 406+/-39, P=0.0004; TTA 69+/-17, P=0.0001). Interestingly, neurocognitive brain function was unaffected in patients undergoing valve repair (7-day follow-up: P300 potentials 386+/-40, P=0.890 versus preop and TTA: 53+/-10, P=0.644; 4-month follow-up: P300 potentials 374+/-36, P=0.166 and TTA 54+/-11, P=0.147). At 4-month follow-up, patients with mechanical prostheses performed worse as compared to valve repair (P300 potentials: P=0.024; TTA P=0.014). CONCLUSION: As shown by P300 auditory evoked potentials and Trailmaking Test A, there is marked neurocognitive damage related to mechanical valve replacement, whereas mitral valve repair does not affect neurocognitive function. This finding supports the beneficial effect of mitral valve repair over mechanical valve replacement in the decision-making tree of borderline cases, which are suitable for both types of procedure.

Adult↗
PubMed2003

Neurocognitive deficit following aortic valve replacement with biological/mechanical prosthesis.

OBJECTIVE: The aim of this study was to objectively measure neurocognitive deficit following aortic valve replacement with a mechanical or biological prosthesis. MATERIALS AND METHODS: In this prospective, contemporary study we followed 82 consecutive patients undergoing isolated aortic valve replacement with either a mechanical (n=29, mean age=52+/-7 years) or a biological (n=53, mean age=68+/-10 years) valve prosthesis. Neurocognitive function was measured by means of objective P300 auditory evoked potentials (peak latencies, ms) and two standard psychometric tests (Trailmaking Test A, Mini Mental State Examination) before the operation, 7 days and 4 months after the operation, respectively. RESULTS: Since P300 peak latencies increase with age, preoperative P300 measures are lower in patients receiving mechanical valves (360+/-35 ms, mean 52 years) as compared to patients receiving biological valves (381+/-34 ms, 68 years, P=0.0001). Seven days after surgery, P300 peak latencies were prolonged (-worsened) in both groups as compared to preoperative values (mechanical valves: 384+/-36 ms; P=0.0001 and biological valves: 409+/-39 ms; P=0.0001). Although on a different level (-age-related), this development was comparable within both groups (P=0.800). Four months after surgery, P300 peak latencies normalized in the mechanical valve group (372+/-27 ms, P=0.857 versus preoperative), while in contrast in the biological valve group they remained prolonged (417+/-37 ms, P=0.0001). We found no difference within patients receiving different types of biological or mechanical aortic valves. CONCLUSION: Postoperative neurocognitive damage is not reversible in (-elderly) patients with biological aortic valve replacement, while in contrast postoperative neurocognitive damage is reversible in (-younger) patients with mechanical valve replacement. For this contrary development, age seems to be most important, whereas damage related to type of valve prosthesis may be overestimated.

Adult↗
PubMed2003

Endovascular stent graft placement in patients with acute thoracic aortic syndromes.

OBJECTIVE: In the present study, the effectiveness of endovascular stent grafts (ESG) in the treatment of acute aortic complications, such as acute dissection type B, penetrating ulcer and traumatic aortic rupture is evaluated. PATIENTS AND METHODS: From June 1997 to February 2002, 66 patients were treated with ESG. Out of this cohort, 19 patients (28.8%) were subjected to stent grafting due to acute aortic syndromes. Acute dissection type B was present in 11 patients (16.6%), a penetrating ulcer was diagnosed in six patients (9%) and in 2 patients (3%) a traumatic aneurysm was the indication for operation. There were 16 male and three female patients with a mean age of 60 years (20-85 years). Excluder stent grafts (Gore) were used in 15 patients, the Talent device (Medtronic) was implanted in four patients. RESULTS: Stent graft placement was technically successful in all patients. Hospital mortality was 0%. Paraparesis occurred in one patient (5.2%), which could be managed successfully without remaining neurological deficit after installation of cerebrospinal fluid drainage for 72h. In another patient, overstenting of the left subclavian artery caused ischemia of the left arm and left subclavian to carotid artery bypass had to be performed. ICU-stay ranged from 1 to 6 days (mean 2.4 days) and the patients could be discharged after an average hospital stay of 8 days. In the follow-up period, one patient died due to myocardial infarction and one patient had to be re-operated due to contained rupture of the thoracic aorta caused by an endoleak. CONCLUSIONS: The study suggests that endovascular stent grafting is an excellent and effective treatment modality for the acute aortic accident, which can be recommended for high-risk patients too. However, close follow-up examination is indicated and long-term results have to be awaited to evaluate the real effectiveness of this method.

Adult↗
PubMed2003

Long-term survival (>10 years) of patients >60 years with induction therapy after cardiac transplantation.

OBJECTIVE: Cardiac transplantation has become an established method for end-stage heart disease. Short- and mid-term outcome has been known to be similar between younger and older (>60 years) recipients. So far, nothing is known about long-term outcome of old patients and the potential long-term effects of antibody induction therapy in these patients. The purpose of this study was to analyse long-term outcome of old cardiac transplant recipients who underwent antibody induction therapy. METHODS: Since 1989, 203 patients (total n = 882) above 60 years have been transplanted at our center. On these patients n = 66 were above 65 years. Survival, incidences of rejection, infection, cancer, graft arteriosclerosis and the amount of renal insufficiency were compared with patients <60 years (n = 679), transplanted during the same period of time. Freedom from specific event was computed by Kaplan-Meier analysis and compared by log-rank test. RESULTS: Ten year survival was similar in all groups (<60 years: 53.7%; 60-64 years: 53.1% and >65 years: 60.2%; P = NS). Causes of death were similar in all patient groups. There were significant fewer rejection episodes in the older patient group (freedom from rejection: 74.9 vs. 83.5 vs. 90.6; P = 0.03). Yet significantly more number of patients >65 years were without steroid maintenance therapy (43.1%) compared to other patient groups (8.2 vs. 9.3%; P < 0.05). There was no difference in overall freedom from severe infection (74.1 vs. 67.7 vs. 85.3%; P = NS), whereas there was a trend towards more CMV disease in the oldest patient group (82.7 vs. 88.6 vs. 70.8%; P=0.06). The incidence of cancer was similar in all groups (freedom from cancer: 82.2 vs. 84.7 vs. 79.1%; P = NS), as well as there was no difference in severe graftsclerosis between all patients (79.2 vs. 93.7 vs. 93.3%; P = NS). There was no difference in development of chronic renal dysfunction (creatinine > 2.0 mg/dl) between the three groups (10 vs. 14 vs. 16%; P = NS). CONCLUSIONS: Old recipients of cardiac transplants have a similar long-term outcome than younger recipients. They were less prone to rejections, had a similar incidence of severe infections and showed a trend towards more CMV disease. All patients had a very low rate of graft arteriosclerosis that was similar amongst the groups. Age-related decline of the immune system further enhanced by immunomodulation of antibody induction therapy might be accounted for the results as well as steroid-free immunosuppression.

Age Factors↗
PubMed2003

Release of neuron-specific enolase and S100 after implantation of cardioverters/defibrillators.

OBJECTIVE: Repeated induction of ventricular fibrillation with ensuing alterations in electroencephalogram and jugular venous oxygen saturation is common practice during insertion of transvenous implantable cardioverters/defibrillators. We investigated whether these functional changes are also associated with cerebral injury. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: We studied 45 patients undergoing implantable cardioverter/defibrillator insertion. Eleven patients with cardiac pacemaker implantation, which was performed in the same manner yet without the necessity to induce ventricular fibrillation, served as controls. MEASUREMENTS AND MAIN RESULTS: Serum neuron-specific enolase and S100 were determined before, immediately postoperatively, and 2 hrs postoperatively. In a randomly composed subgroup, neuron-specific enolase was also determined 6 and 24 hrs after surgery. Implantable cardioverter/defibrillator patients only showed an increase of both markers postoperatively. Median neuron-specific enolase values climbed from a preoperative 9.9 to 12.3 and 14.4 microg/L at 2 and 24 hrs after surgery, respectively. This increase was associated with the number of shocks and the cumulative time in circulatory arrest. The highest median S100 level (0.075 microg/L) was reached 2 hrs after the procedure. Neuron-specific enolase and S100 were extremely elevated (13.7 and 0.970 microg/L, respectively) in one patient after an extended episode of ventricular fibrillation. Plasma hemoglobin levels were in the normal range in implantable cardioverter/defibrillator patients throughout the observation period. CONCLUSIONS: Apparently, even brief successive periods of global cerebral ischemia cause neuronal damage without obvious severe neurologic deficits. However, they may be related to subtle postoperative neurologic or cognitive dysfunctions that a number of implantable cardioverter/defibrillator patients exhibit after implantation.

Aged↗
PubMed2003

Fibrinolytic balance of the arterial wall: pulmonary artery displays increased fibrinolytic potential compared with aorta.

Classic pulmonary thromboembolism research has documented that large pulmonary thromboemboli lyse spontaneously, suggesting potent fibrinolytic activity in human pulmonary artery (Pa). This concept conflicts with published animal studies in which the proximal Pa was reported to be devoid of tissue plasminogen activator (t-PA) expression. The current study used in situ hybridization protocols to demonstrate t-PA expression in samples of human main Pa (n = 30). Real-time PCR was used to demonstrate quantitatively that the levels of t-PA transcripts were higher than those of its primary regulator [ie, plasminogen activator-inhibitor 1 (PAI-1)] in the Pa samples. Immunologic and functional assays extended these observations by demonstrating that levels of t-PA antigen were higher than PAI-1 antigen, which resulted in the detection of free t-PA activity. This contrasted with the fibrinolytic balance of matched samples of aorta (n = 6) in which PAI-1 transcripts and antigen values were higher than the corresponding t-PA values, and only M(r) 110 kDa t-PA-PAI-1 complexes could be detected in functional assays. To assess the relative fibrinolytic contribution of the endothelial cell layer, Pa endothelial cells and aortic endothelial cells were scraped and propagated in culture for 20 +/- 6 days. Pa endothelial cell-conditioned media revealed increased t-PA/PAI-1 antigen ratios. Taken together, our data indicate that the balance between t-PA and PAI-1 is shifted in human main Pa to favor net PA activity.

Aorta, Thoracic↗
PubMed2003

The impact of asymptomatic carotid artery disease on the intraoperative course of coronary artery bypass surgery.

Asymptomatic carotid artery stenosis (CAS) may result in neurological injury after coronary artery bypass surgery, but routine preoperative carotid screening is not undisputed. We studied whether routinely determined carotid duplex results, beyond detecting high-risk patients, additionally influence intraoperative course. One hundred and eight patients without new signs of impaired cerebral circulation were investigated. Anesthesiology, perfusionist records, and patient files were reviewed for patient characteristics, intraoperative variables and postoperative neurological sequelae. There was a higher incidence of prior cerebrovascular events and peripheral artery disease in CAS patients (p < 0.05). Pulsatile flow was employed more frequently in this group (p < 0.05). Severe hyperventilation, hyperglycemia, hemodilution, hyperthermia, and lactacidosis were avoided in both groups. However, labile hemodynamics of CAS patients required more corrective interventions (p < 0.05). There was also a tendency toward greater mortality. Stroke and transient ischemic attack (TIA) occurred in two patients without CAS. Since CAS was associated with a greater degree of cardiovascular instability requiring frequent measures to control hemodynamics, positive duplex results should heighten vigilance. Although CAS does not appear to be the major source of cerebral ischemia, it involves significant comorbidity.

Aged↗
PubMed2003

Redo coronary artery bypass grafting with and without cardiopulmonary bypass in the elderly.

OBJECTIVES: Morbidity and mortality rates rise with increasing age in patients undergoing conventional redo coronary artery bypass grafting (CABG). The aim of this study was to compare our experience of minimal tissue dissection and target vessel revascularization without cardiopulmonary bypass (CPB) with the standard procedure of total dissection of the heart and complete revascularization with CPB for a population of elderly patients undergoing elective redo coronary artery CABG. METHODS: We retrospectively analyzed morbidity, mortality, and functional status of 47 patients older than 75 years who underwent redo CABG between January 1995 and June 2002. Thirty-one patients underwent redo CABG with CPB, and 16 patients underwent redo CABG without CPB. Follow-up end points were defined by patient survival, freedom from recurrence of angina (Canadian Cardiovascular Society [CCS] score), freedom from rehospitalizations and reinterventions, and the need for antianginal medication. RESULTS: There were 2 perioperative deaths (2 in the CPB group versus 0 in the group without CPB; P =.151). Nonfatal myocardial infarction occurred in 3 patients (3 in the CPB group versus 0 in the group without CPB; P =.082). Major adverse cardiac events occurred in 5 patients (5 in the CPB group versus 0 in the group without CPB; P =.058). At the time of follow-up, the mean CCS score of patients who underwent redo CABG with CPB was 1.5 +/- 0.8 and was 1.6 +/- 0.7 for patients who underwent redo CABG without CPB (P =.432). The rates of angina recurrence (16% with CPB versus 13.3% without CPB; P =.243), use of nitrates (8.7% with CPB versus 14.3% without CPB; P =.542), and survival (89% with CPB versus 93% without CPB; P =.238) were very comparable for the two groups. CONCLUSIONS: In this high-risk subgroup of patients, those patients who underwent target vessel revascularization without CPB showed a trend toward a lower rate of major adverse cardiac events, and this procedure seems promising with regard to long-term outcome. Therefore, target vessel revascularization may be offered liberally to elderly patients who are at high risk in surgeries involving complete revascularization with CPB. Further studies are needed to elucidate the long-term outcome of target vessel revascularization for elderly patients undergoing redo CABG.

Aged↗
PubMed2002

Cognitive deficit after aortic valve replacement.

BACKGROUND: Impairment of cognitive brain function after coronary artery bypass grafting (CABG) is well known. In contrast the potential neurocognitive damage related to aortic valve replacement (AVR) is uncertain. METHODS: In this contemporary case-matched control study we followed 30 patients (mean age 70 years) receiving isolated AVR with a biological prosthesis. A cohort of sex-and age-matched patients (n = 30, mean age 70 years) receiving CABG with cardiopulmonary bypass served as controls. Cognitive brain function was measured by means of auditory evoked P300 potentials (peak latencies, ms) before the operation and 7 days and 4 months after the operation. Additionally, two standard psychometric tests (Mini-Mental State Examination and the Trailmaking Test A) were performed. RESULTS: In preoperative measures there was no difference between patients undergoing AVR and patients undergoing CABG (AVR 378 +/- 37 ms, CABG 374 +/- 32 ms, p = 0.629). One week after surgery P300 peak latencies were prolonged (impaired) in both groups compared with preoperative values (AVR 405 +/- 43 ms, p = 0.001; CABG 398 +/- 44 ms, p = 0.004). At this point of follow-up there was no difference between the groups (p = 0.607). Finally, 4 months after surgery P300 auditory evoked potentials returned to normal in the CABG group (380 +/- 24 ms, p = 0.940) while in contrast in the valve group they continued to become prolonged (worsened) compared with preoperative values (410 +/- 47 ms, p = 0.005). At this time of follow-up P300 peak latencies were prolonged in AVR patients as compared with CABG patients (p = 0.032). The Trailmaking Test A and Mini-Mental State Examination failed to discriminate any difference. CONCLUSIONS: Four-month impairment of cognitive brain function is more pronounced in patients undergoing biological AVR as compared with age-matched control patients undergoing CABG. Further studies are needed to clarify the potential pathologic mechanisms causing an ongoing cognitive impairment in patients with biological aortic valve prostheses.

Aged↗
PubMed2002

Combined surgical and endovascular treatment of acute aortic dissection type A: preliminary results.

BACKGROUND: The established treatment modality of acute Stanford type A dissection includes repair of the ascending aorta and various portions of the aortic arch, whereas the descending aorta is left untreated. We report a simultaneous approach of open repair of the ascending aorta with transluminal stent grafting of the descending aorta to minimize the consequences of an untreated descending aorta. METHODS: From April 2001 to February 2002, 8 consecutive patients (3 women [37.5%] and 5 men [62.5%]) with a mean age of 55.7 years (range, 45 to 70 years) were intended to be treated with the combined method of surgical repair of the ascending aorta and transluminal stent grafting into the descending aorta during the period of deep hypothermic circulatory arrest. Circulatory arrest time ranged between 30 and 67 minutes (average, 38.8 minutes). Specially designed Talent stent grafts (32 to 40 mm in diameter, length 13 cm) were inserted under direct vision and deployed with the proximal end at the origin of the left subclavian artery. RESULTS: Intraoperative stent graft placement was successful in 7 patients (87.5%). Because of severe kinking of the distal arch, stent insertion failed in 1 patient (12.5%). One patient with a history of preoperative stroke in the middle cerebral artery died because of intracerebral bleeding on postoperative day 2, resulting in an in-hospital mortality of 12.5%. Mean intensive care unit stay was 6.4 days (range, 2 to 21 days) and overall hospital stay was 18.2 days (range, 7 to 33 days). Completion computed tomographic scans revealed complete thrombosis of the false lumen in 2 patients and partial thrombosis in 4 patients. Follow-up was complete and ranged from 1 to 9 months (mean, 5.4 months). CONCLUSIONS: This preliminary study shows that combined surgical and endovascular treatment of acute type A dissection is feasible, and at least partial thrombosis of the false lumen can be achieved, potentially minimizing the risk of further dilatation or rupture. Additionally, the stent graft expands the otherwise sickle-shaped true lumen, thereby ameliorating distal aortic perfusion. Long-term results are warranted to demonstrate the effectiveness of this new combined treatment modality.

Acute Disease↗
PubMed2002

The vacuum-assisted closure system for the treatment of deep sternal wound infections after cardiac surgery.

BACKGROUND: The VAC system (vacuum-assisted wound closure) is a noninvasive active therapy to promote healing in difficult wounds that fail to respond to established treatment modalities. The system is based on the application of negative pressure by controlled suction to the wound surface. The method was introduced into clinical practice in 1996. Since then, numerous studies proved the effectiveness of the VAC System on microcirculation and the promotion of granulation tissue proliferation. METHODS: Eleven patients (5 men, 6 women) with a median age of 64.4 years (range 50 to 78 years) with sternal wound infection after cardiac surgery (coronary artery bypass grafting = 5, aortic valve replacement = 5, ascending aortic replacement = 1) were fitted with the VAC system by the time of initial surgical debridement. RESULTS: Complete healing was achieved in all patients. The VAC system was removed after a mean of 9.3 days (range 4 to 15 days), when systemic signs of infection resolved and quantitative cultures were negative. In 6 patients (54.5%), the VAC system was used as a bridge to reconstructive surgery with a pectoralis muscle flap, and in the remaining 5 patients (45.5%), primary wound closure could be achieved. Intensive care unit stay ranged from 1 to 4 days (median 1 day). Duration of hospital stay varied from 13 to 45 days (median 30 days). In-hospital mortality was 0%, and 30-day survival was 100%. CONCLUSIONS: The VAC system can be considered as an effective and safe adjunct to conventional and established treatment modalities for the therapy of sternal wound infections after cardiac surgery.

Aged↗
PubMed2002

Fluid dynamics, wall mechanics, and oxygen transfer in peripheral bypass anastomoses.

Intimal hyperplasia at vascular anastomoses seems to be promoted by altered flow conditions and stress distributions within the anastomotic region. In order to gain deeper insight into postoperative disease processes, and subsequently, to contribute to the development of improved vascular reconstructions, detailed studies, also on local flow dynamics and related mass transport and wall mechanical effects, are required. In context with in vivo studies, computer simulation based on casts of femoro-popliteal bypasses implanted into sheep were performed to analyze the flow dynamics, the oxygen transport, and the wall and suture mechanics in anatomically correct bypass configurations related to three established surgical techniques and resulting geometries (conventional type anastomosis, Taylor-patch and Miller-cuff anastomoses with venous interposition grafts of different modifications). The influence of geometry, compliance of the graft, the interponated vein patch and vein cuff, and of the artery was included. Time-dependent, three-dimensional Navier-Stokes equations describing the flow field, and a nonlinear shell structure for the vessel walls were coupled using finite element methods. The numerical results demonstrate nonphysiological flow patterns in the anastomotic region. Strongly skewed axial velocity profiles and secondary velocities occur in the junction region. In the Miller-cuff a vortex may induce a wash-out effect which protects the host artery. On the artery floor opposite the junction flow separation and zones of recirculation were found. The analysis of oxygen transport illustrates a correlation between zones of low wall shear stress and reduced oxygen flux into the wall. Wall mechanics show that increased compliance mismatch leads to increased and discontinuous intramural stresses. Comparison to histomorphological findings on intimal hyperplasia shows certain correlations, particularly increased compliance mismatch has a proliferate influence on suture line hyperplasia. The reduction of compliance mismatch using vein interposition results in decreased generation of intimal hyperplasia, and therefore, contributes to improvement of patency rates, while the geometrical modification and the resulting change of the flow pattern seems to be less important for the growth of anastomotic intimal hyperplasia.

Anastomosis, Surgical↗