Aura Cernaianu - Academia.edu (original) (raw)

Papers by Aura Cernaianu

Vascular and Endovascular Surgery, 1992

Cardiovascular Surgery, 1995

Nitroglycerin has been reported to induce heparin resistance in clinical studies, however this ef... more Nitroglycerin has been reported to induce heparin resistance in clinical studies, however this effect is controversial, and recent controlled clinical and in vitro studies do not support this finding. An in vitro study was designed to evaluate nitroglycerin-induced heparin resistance. Six adult New Zealand white rabbits underwent weekly phlebotomy (n = 43). Samples were mixed with; 1.5 IU (0.15 ml) bovine sodium heparin/mi blood (Group I), 1.5 IU bovine sodium heparin/ml blood in combination with nitroglycerin 250 ~g/ml blood (Group 11), nitroglycerin 250 I~g/ml blood (Group liD, 0.15 ml normal saline mixed with nitroglycerin 250 ~g/ml blood (Group IV). A drug-free control was established (Group V). Activated clotting time (ACT), activated partial thromboplastin time (APTF), and prothrombin time (PT) were calculated for all groups. In group I, ACT, APTT, and PT were 265 ± 80, 111 ± 23 and 32 __ 13 s, respectively. In group I1, ACT, APTT and PT were 210 ± 55, 89 ± 18, and 30 ± 15 s, respectively. All differences were statistically significant. No differences were identified between controls and the group that received nitroglycerin alone or in combination with saline. Heparin ant±coagulation is significantly antagonized by the concomitant administration of therapeutic levels of nitroglycerin in vitro. Nitroglycerin-induced heparin resistance may be a significant issue in determining the safety and efficacy of concurrent medical therapy. Caution is advised in characterization of coagulation profiles in the presence of heparin and nitroglycerin.

Cardiovascular Surgery, 1995

PURPOSE: To investigate the immunological characteristics of abdominal aortic aneurysm (AAA). MET... more PURPOSE: To investigate the immunological characteristics of abdominal aortic aneurysm (AAA). METHODS: Twelve patients (10 males, 2 females) with AAA were studied. Ages ranged from 67 to 77 years (mean = 73 years). Before operation, peripheral blood samples were obtained in order to measure the white blood cell count, lymphocyte count and the lymphocyte subpopulations CD3, CD4, CD8 and CD20. The lymphocyte subpopulations were assessed using laser flow cytometric methods with specific monoclonal antibodies against CD3, CD4, CD8 and CD20 (expressed by T cell, helper T cell, suppressor T cell and B cell, respectively). In eight patients, we tested for CD3, CD4, CD8 and CD20 in the AAA specimens with enzymatic antibodies using immunostaining methods. RESULTS: The white blood cell and lymphocyte counts were within normal limits, except in one case. In peripheral blood samples, the CD3 level in only two cases (51.2% and 54.5%) were lower than is normal (61.7-77.3%). CD8 levels in only two cases (13%, 16.6%) were lower than is normal (20-41.4%). CD4, CD20 and CD4/CD8 estimations were within normal limits in all cases. In the AAA specimens, CD3 was positive in 6 cases, CD4 positive in 7 and CD8 positive in 2. CD20 was negative in all cases. CONCLUSIONS: 1. Lymphocyte subpopulations in patients with AAA did not show specific characteristics in peripheral blood samples. 2. Most of the lymphocytes which infiltrated into the aneurysreal wall were T cells, especially helper T cells.

Cardiovascular Surgery, 1995

Overall hospital mortality was 36.8% (28•76). Significant associations with non-survival were fou... more Overall hospital mortality was 36.8% (28•76). Significant associations with non-survival were found as expected with higher alSS and initial hypotension. However, survival was not associated (P = ns) with time from injury to admission or aortography, or from aortography to aortic surgery, nor with direct admission versus referral, nor the need for other prethoracotomy surgery. Surprisingly, much longer times (> 2 hours), also found within the direct admit and referred groups, were taken from injury to aortic surgery in the survivor group. These data form the basis for finding where it may be feasible to shorten time intervals when developing improved practice guidelines for TAR. The risk of spontaneous rupture during these long time intervals from injury to surgery remains to be analyzed.

Cardiovascular Surgery, 1995

The coincidence of coronary and carotid artery disease (uni-or bilateral, with or without involve... more The coincidence of coronary and carotid artery disease (uni-or bilateral, with or without involvement of the supra-aortic branch) is still a problem with regards to surgical strategy. Since the opening of the Heart Centre Duisburg in 1989 the authors have favoured a simultaneous approach to lesions in both arterial systems in order to avoid myocardial infarction or stroke. The aim of this retrospective study was to review the early and late results of the combined procedures for the endpoints of death, myocardial infarction and stroke. During a 7-year period (1990-1997) a total of 18,050 patients underwent cardiac surgery and extracorporeal circulation. Simultaneous intervention in both arterial systems was performed in 313 patients (1.73%). All patients underwent preoperative ultrasonic diagnostics, digital substraction angiography, neurological examination and cardiac catheterization. The principal indication was the need for myocardial revascularization, and symptomatic or asymptomatic carotid stenosis of 80% diameter reduction or more (with or without contralateral disease). The mean age was 66.4 Ϯ 6.9 years; 240 patients (76.7%) were male, 73 patients (23.3%) female; 243 patients (77.6%) had triple-vessel disease, 82 patients (26.2%) had left main stenosis and 94 patients (43.5%) had a reduced ejection fraction. A total of 171 patients (54.6%) had a previous myocardial infarction, 54 patients (17.3%) presented with unstable angina and nine patients (2.9%) had prior coronary artery bypass grafts. Eighty-seven patients (27.8%) had an internal carotid artery stenosis on the right side, 75 patients (24%) on the left side and 151 patients (48.2%) lesions in both carotid arteries. Prior carotid endarterectomy was performed in 14 patients (4.5%), and the contralateral carotid was occluded in 24 patients (7.7%). Fifty patients had a previous stroke (16%) and 185 patients (59.1%) were asymptomatic. During surgery, the the carotid artery was first exposed, followed by median sternotomy, systemic heparinization, cannulation and cardiopulmonary bypass. After achieving mild hypothermia (30°C), endarterectomy was performed with a venous patch closure. An occluded contralateral carotid artery was always an indication for shunting. Coronary artery bypass grafting was carried out with intermittent cross-clamping under moderate hypothermia (22-27°C). Ten patients suffered a myocardial infarction (3.2%), seven patients (2.2%) had an apoplectic insult perioperatively ( Ͻ 30 days) and one patient (0.3%) had an event during long-term follow-up. Early overall mortality was 28 (8.9%), of which 13 were cardiac related (4.2%). Overall late mortality was eight (2.6%), of which six were cardiac related (1.9%). Mean survival time was 6.18 years. Simultaneous carotid endarterectomy and myocardial revascularization can be justified as a routine surgical management of severe lesions in both arterial systems. The risk of myocardial infarction, apoplectic stroke or mortality was not significantly

Cardiovascular Surgery, 1995

The risks of allogeneic transfusion are well known to cardiovascular surgeons and have prompted a... more The risks of allogeneic transfusion are well known to cardiovascular surgeons and have prompted a search for alternatives. Perfluorocarbons were introduced into clinical trials in the early 1980s with the hope that these products would develop into acceptable blood substitutes. Unfortunately, the limited potency, short half-life, and potential toxicity of these early formulations, coupled with unrealistic expectations for efficacy, prevented the perfluorocarbons from playing a significant role in transfusion medicine. Recent changes in formulation to improve efficacy and eliminate toxicity have stimulated renewed interest in perfluorocarbons as alternatives to allogeneic transfusion.

Cardiovascular Surgery, 1995

Journal of Cardiothoracic and Vascular Anesthesia, 1991

Circulation, 1987

Twenty-three lonescu-Shiley standard bovine pericardial bioprostheses (15 aortic, seven mitral, a... more Twenty-three lonescu-Shiley standard bovine pericardial bioprostheses (15 aortic, seven mitral, and one tricuspid) removed at surgery from 21 adults, 28 to 75 years old (mean 55 at reoperation), were examined after functioning for as long as 84 months (mean 26). Reoperation was necessitated by active or healed endocarditis (10 valves), paravalvular leak (three), structural deterioration (eight), and other causes (two). Valves with degenerative dysfunction functioned 32 to 84 months (mean 68). Six had intrinsic cuspal calcification, one with stenosis, and there was regurgitation through secondary cuspal defects in five. Six valves had cuspal defects clearly associated with commissural sutures ("alignment stitches") unique to this valve design. One valve had a large basal cuspal tear. Other prominent pathologic features included gross cuspal thickening and mild stretching and microscopic deep fluid insudation, separation of collagen bundles, and mononuclear inflammation. Thus, structural disruption due to calcific tissue degeneration and design-related cuspal tears or commissural perforations are the predominant modes of degenerative failure of Ionescu-Shiley standard bovine pericardial valves. Circulation 76, No. 3, 618-627, 1987. clinical observations suggest that degenerative failures are related to cuspal tearing, calcification, or both,6j9 12-14 there has not been detailed description 618 ofremoved valves. Two previous studies that examined the detailed morphologic features of removed pericardial valves were limited with respect to duration of valve function and specimen number.'5 16 particular the extent to which specific degenerative mechanisms will limit the long-term durability and the pathologic correlates of extended function of pericardial bioprostheses are largely yet unknown. The purpose of this study was to investigate the causes of failure and morphologic spectrum of Ionescu-Shiley bovine pericardial valves removed at reoperation at a single institution, with emphasis on long-term structural changes.

CHEST Journal, 1992

Of all patients presenting at our level 1 trauma center with multiorgan system injuries, 33 have ... more Of all patients presenting at our level 1 trauma center with multiorgan system injuries, 33 have been identified with acute lesions of the thoracic aorta. Mean severity injury score was 24 +/- 3. Four patients underwent resuscitative thoracotomy upon arrival in the emergency department. One survived and fully recovered. The rest underwent diagnostic procedures and repair of aortic lesions in conjunction with surgical treatment of other injured organ systems. The overall survival rate was 82 percent. Survivors arrived significantly faster to the ED and had lesser degree of multiorgan system injuries. There was no difference in the time spent to make the diagnosis of acute aortic disruption for survivors and nonsurvivors, nor was a difference in time to arrive in the operating room once the diagnosis of aortic injury has been established. Morbidity was related to ischemia to distal organs in four patients of whom two presented with multiple lesions of the thoracic aorta; two remained paralyzed and two had only lower limb spasticity. All discharged survivors were alive at 12 months' follow-up. The type of surgical repair did not influence the outcome of patients with single, typical aortic lesions; however, "clamp/sew" technique was not adequate when multiple aortic tears were found intraoperatively. The outcome of surgical treatment of the traumatic aortic lesions of patients with polytrauma may be influenced by the speed of arrival to the ED, the magnitude of multiorgan system involvement, and the application of appropriate surgical technique for repair according to the intrathoracic findings and the timing of aortic repair vis-a-vis other surgical treatment.

Vascular and Endovascular Surgery, 1992

Cardiovascular Surgery, 1995

Nitroglycerin has been reported to induce heparin resistance in clinical studies, however this ef... more Nitroglycerin has been reported to induce heparin resistance in clinical studies, however this effect is controversial, and recent controlled clinical and in vitro studies do not support this finding. An in vitro study was designed to evaluate nitroglycerin-induced heparin resistance. Six adult New Zealand white rabbits underwent weekly phlebotomy (n = 43). Samples were mixed with; 1.5 IU (0.15 ml) bovine sodium heparin/mi blood (Group I), 1.5 IU bovine sodium heparin/ml blood in combination with nitroglycerin 250 ~g/ml blood (Group 11), nitroglycerin 250 I~g/ml blood (Group liD, 0.15 ml normal saline mixed with nitroglycerin 250 ~g/ml blood (Group IV). A drug-free control was established (Group V). Activated clotting time (ACT), activated partial thromboplastin time (APTF), and prothrombin time (PT) were calculated for all groups. In group I, ACT, APTT, and PT were 265 ± 80, 111 ± 23 and 32 __ 13 s, respectively. In group I1, ACT, APTT and PT were 210 ± 55, 89 ± 18, and 30 ± 15 s, respectively. All differences were statistically significant. No differences were identified between controls and the group that received nitroglycerin alone or in combination with saline. Heparin ant±coagulation is significantly antagonized by the concomitant administration of therapeutic levels of nitroglycerin in vitro. Nitroglycerin-induced heparin resistance may be a significant issue in determining the safety and efficacy of concurrent medical therapy. Caution is advised in characterization of coagulation profiles in the presence of heparin and nitroglycerin.

Cardiovascular Surgery, 1995

PURPOSE: To investigate the immunological characteristics of abdominal aortic aneurysm (AAA). MET... more PURPOSE: To investigate the immunological characteristics of abdominal aortic aneurysm (AAA). METHODS: Twelve patients (10 males, 2 females) with AAA were studied. Ages ranged from 67 to 77 years (mean = 73 years). Before operation, peripheral blood samples were obtained in order to measure the white blood cell count, lymphocyte count and the lymphocyte subpopulations CD3, CD4, CD8 and CD20. The lymphocyte subpopulations were assessed using laser flow cytometric methods with specific monoclonal antibodies against CD3, CD4, CD8 and CD20 (expressed by T cell, helper T cell, suppressor T cell and B cell, respectively). In eight patients, we tested for CD3, CD4, CD8 and CD20 in the AAA specimens with enzymatic antibodies using immunostaining methods. RESULTS: The white blood cell and lymphocyte counts were within normal limits, except in one case. In peripheral blood samples, the CD3 level in only two cases (51.2% and 54.5%) were lower than is normal (61.7-77.3%). CD8 levels in only two cases (13%, 16.6%) were lower than is normal (20-41.4%). CD4, CD20 and CD4/CD8 estimations were within normal limits in all cases. In the AAA specimens, CD3 was positive in 6 cases, CD4 positive in 7 and CD8 positive in 2. CD20 was negative in all cases. CONCLUSIONS: 1. Lymphocyte subpopulations in patients with AAA did not show specific characteristics in peripheral blood samples. 2. Most of the lymphocytes which infiltrated into the aneurysreal wall were T cells, especially helper T cells.

Cardiovascular Surgery, 1995

Overall hospital mortality was 36.8% (28•76). Significant associations with non-survival were fou... more Overall hospital mortality was 36.8% (28•76). Significant associations with non-survival were found as expected with higher alSS and initial hypotension. However, survival was not associated (P = ns) with time from injury to admission or aortography, or from aortography to aortic surgery, nor with direct admission versus referral, nor the need for other prethoracotomy surgery. Surprisingly, much longer times (> 2 hours), also found within the direct admit and referred groups, were taken from injury to aortic surgery in the survivor group. These data form the basis for finding where it may be feasible to shorten time intervals when developing improved practice guidelines for TAR. The risk of spontaneous rupture during these long time intervals from injury to surgery remains to be analyzed.

Cardiovascular Surgery, 1995

The coincidence of coronary and carotid artery disease (uni-or bilateral, with or without involve... more The coincidence of coronary and carotid artery disease (uni-or bilateral, with or without involvement of the supra-aortic branch) is still a problem with regards to surgical strategy. Since the opening of the Heart Centre Duisburg in 1989 the authors have favoured a simultaneous approach to lesions in both arterial systems in order to avoid myocardial infarction or stroke. The aim of this retrospective study was to review the early and late results of the combined procedures for the endpoints of death, myocardial infarction and stroke. During a 7-year period (1990-1997) a total of 18,050 patients underwent cardiac surgery and extracorporeal circulation. Simultaneous intervention in both arterial systems was performed in 313 patients (1.73%). All patients underwent preoperative ultrasonic diagnostics, digital substraction angiography, neurological examination and cardiac catheterization. The principal indication was the need for myocardial revascularization, and symptomatic or asymptomatic carotid stenosis of 80% diameter reduction or more (with or without contralateral disease). The mean age was 66.4 Ϯ 6.9 years; 240 patients (76.7%) were male, 73 patients (23.3%) female; 243 patients (77.6%) had triple-vessel disease, 82 patients (26.2%) had left main stenosis and 94 patients (43.5%) had a reduced ejection fraction. A total of 171 patients (54.6%) had a previous myocardial infarction, 54 patients (17.3%) presented with unstable angina and nine patients (2.9%) had prior coronary artery bypass grafts. Eighty-seven patients (27.8%) had an internal carotid artery stenosis on the right side, 75 patients (24%) on the left side and 151 patients (48.2%) lesions in both carotid arteries. Prior carotid endarterectomy was performed in 14 patients (4.5%), and the contralateral carotid was occluded in 24 patients (7.7%). Fifty patients had a previous stroke (16%) and 185 patients (59.1%) were asymptomatic. During surgery, the the carotid artery was first exposed, followed by median sternotomy, systemic heparinization, cannulation and cardiopulmonary bypass. After achieving mild hypothermia (30°C), endarterectomy was performed with a venous patch closure. An occluded contralateral carotid artery was always an indication for shunting. Coronary artery bypass grafting was carried out with intermittent cross-clamping under moderate hypothermia (22-27°C). Ten patients suffered a myocardial infarction (3.2%), seven patients (2.2%) had an apoplectic insult perioperatively ( Ͻ 30 days) and one patient (0.3%) had an event during long-term follow-up. Early overall mortality was 28 (8.9%), of which 13 were cardiac related (4.2%). Overall late mortality was eight (2.6%), of which six were cardiac related (1.9%). Mean survival time was 6.18 years. Simultaneous carotid endarterectomy and myocardial revascularization can be justified as a routine surgical management of severe lesions in both arterial systems. The risk of myocardial infarction, apoplectic stroke or mortality was not significantly

Cardiovascular Surgery, 1995

The risks of allogeneic transfusion are well known to cardiovascular surgeons and have prompted a... more The risks of allogeneic transfusion are well known to cardiovascular surgeons and have prompted a search for alternatives. Perfluorocarbons were introduced into clinical trials in the early 1980s with the hope that these products would develop into acceptable blood substitutes. Unfortunately, the limited potency, short half-life, and potential toxicity of these early formulations, coupled with unrealistic expectations for efficacy, prevented the perfluorocarbons from playing a significant role in transfusion medicine. Recent changes in formulation to improve efficacy and eliminate toxicity have stimulated renewed interest in perfluorocarbons as alternatives to allogeneic transfusion.

Cardiovascular Surgery, 1995

Journal of Cardiothoracic and Vascular Anesthesia, 1991

Circulation, 1987

Twenty-three lonescu-Shiley standard bovine pericardial bioprostheses (15 aortic, seven mitral, a... more Twenty-three lonescu-Shiley standard bovine pericardial bioprostheses (15 aortic, seven mitral, and one tricuspid) removed at surgery from 21 adults, 28 to 75 years old (mean 55 at reoperation), were examined after functioning for as long as 84 months (mean 26). Reoperation was necessitated by active or healed endocarditis (10 valves), paravalvular leak (three), structural deterioration (eight), and other causes (two). Valves with degenerative dysfunction functioned 32 to 84 months (mean 68). Six had intrinsic cuspal calcification, one with stenosis, and there was regurgitation through secondary cuspal defects in five. Six valves had cuspal defects clearly associated with commissural sutures ("alignment stitches") unique to this valve design. One valve had a large basal cuspal tear. Other prominent pathologic features included gross cuspal thickening and mild stretching and microscopic deep fluid insudation, separation of collagen bundles, and mononuclear inflammation. Thus, structural disruption due to calcific tissue degeneration and design-related cuspal tears or commissural perforations are the predominant modes of degenerative failure of Ionescu-Shiley standard bovine pericardial valves. Circulation 76, No. 3, 618-627, 1987. clinical observations suggest that degenerative failures are related to cuspal tearing, calcification, or both,6j9 12-14 there has not been detailed description 618 ofremoved valves. Two previous studies that examined the detailed morphologic features of removed pericardial valves were limited with respect to duration of valve function and specimen number.'5 16 particular the extent to which specific degenerative mechanisms will limit the long-term durability and the pathologic correlates of extended function of pericardial bioprostheses are largely yet unknown. The purpose of this study was to investigate the causes of failure and morphologic spectrum of Ionescu-Shiley bovine pericardial valves removed at reoperation at a single institution, with emphasis on long-term structural changes.

CHEST Journal, 1992

Of all patients presenting at our level 1 trauma center with multiorgan system injuries, 33 have ... more Of all patients presenting at our level 1 trauma center with multiorgan system injuries, 33 have been identified with acute lesions of the thoracic aorta. Mean severity injury score was 24 +/- 3. Four patients underwent resuscitative thoracotomy upon arrival in the emergency department. One survived and fully recovered. The rest underwent diagnostic procedures and repair of aortic lesions in conjunction with surgical treatment of other injured organ systems. The overall survival rate was 82 percent. Survivors arrived significantly faster to the ED and had lesser degree of multiorgan system injuries. There was no difference in the time spent to make the diagnosis of acute aortic disruption for survivors and nonsurvivors, nor was a difference in time to arrive in the operating room once the diagnosis of aortic injury has been established. Morbidity was related to ischemia to distal organs in four patients of whom two presented with multiple lesions of the thoracic aorta; two remained paralyzed and two had only lower limb spasticity. All discharged survivors were alive at 12 months' follow-up. The type of surgical repair did not influence the outcome of patients with single, typical aortic lesions; however, "clamp/sew" technique was not adequate when multiple aortic tears were found intraoperatively. The outcome of surgical treatment of the traumatic aortic lesions of patients with polytrauma may be influenced by the speed of arrival to the ED, the magnitude of multiorgan system involvement, and the application of appropriate surgical technique for repair according to the intrathoracic findings and the timing of aortic repair vis-a-vis other surgical treatment.