Naser Qedra - Academia.edu (original) (raw)

Papers by Naser Qedra

Zeitschrift f�r Herz-, Thorax- und Gef��chirurgie, 1999

ABSTRACT Der Einsatz der extrakorporalen Zirkulation führt zu einer erheblichen Stimulation der p... more ABSTRACT Der Einsatz der extrakorporalen Zirkulation führt zu einer erheblichen Stimulation der proinflammatorischen Reaktion. Dies kann bewirken, daß die zeitgerechte Diagnosestellung einer Infektion postoperativ erschwert wird und zeigt den Bedarf nach einem zuverläßigeren Sepsismarker in der postoperativen Phase nach herzchirurgischen Eingriffen. Wir bestimmten den neuen Sepsismarker Procalcitonin (PCT) in zwei unterschiedlichen Patientengruppen, die jeweils dem Kontakt mit extrakorporalen Kreislaufsystemen ausgesetzt waren. Die erste Gruppe (VAD-Gruppe) bestand aus 38 Patienten mit terminalem Herzversagen, die mit einem ventrikulären Unterstützungssystem Typ Berlin Heart versorgt wurden. Die zweite Gruppe (EKZ-Gruppe) bestand aus 713 Patienten, die einem konventionellen herzchirurgischen Operationsverfahren unterzogen wurden. PCT wurde vor Operation und täglich nach der Operation gemessen. In der VAD-Gruppe waren die präoperativen PCT-Werte in der Lage, Patienten im kardiogenen Schock zu identifizieren, die nach der Operation an einer Infektion verstarben. Darüberhinaus hatten die Patienten, die vor Herztransplantation immer noch erhöhte PCT-Werte aufwiesen, eine schlechte Prognose nach Transplantation. In der EKZ-Gruppe hatte kein Patient erhöhte PCT-Werte vor Operation. Patienten mit erhöhten Werten am ersten postoperativen Tag hatten eine hohe Inzidenz von Komplikationen in ihrem weiteren Verlauf, während Patienten ohne PCT-Erhöhung einen unkomplizierten Verlauf nahmen. Sowohl bei Patienten mit kardiogenem Schock als auch nach Einsatz der Herz-Lungen-Maschine ist Procalcitonin in der Lage, bakterielle und pilzbedingte Infektionen zu identifizieren. Daher kann es zur Beurteilung der Transplantabilität von Patienten an Kreislaufunterstützungssystemen herangezogen werden. Der PCT-Wert scheint vom Blutkontakt zu Fremdoberflächen nicht beeinflußt zu werden. Allerdings zeigen eine Reihe von Patienten nach herzchirurgischen Routineeingriffen einen PCT-Verlauf. Die Komplikationsinzidenz ist in dieser Gruppe deutlich erhöht. Möglicherweise ist der PCT-Anstieg auf eine intestinale Minderperfusion während der extrakorporalen Zirkulation zurückzuführen. The use of extracorporal circulation in open heart surgery causes profound stimulation of proinflammatory reaction. Therefore, timely diagnosis of infectious complications may become extremely difficult, and a more reliable marker of sepsis under these circumstances is needed. We measured the new marker for sepsis Procalcitonin (PCT) in two distinct groups of patients exposed to extracorporeal circulatory devices. Group VAD consisted of 38 patients in end-stage heart failure supported with ventricular assist devices (VAD) Type Berlin Heart. Group EEC included 713 patients undergoing standard open heart surgery procedures. PCT was measured before operation and daily thereafter. PCT levels before operation were able to identify patients in cardiogenic shock who after device implantation died of infectious complications. Patients on VAD who showed elevated PCT levels before heart transplantation had a very unfavorable outcome. In the ECC group, none of the patients had elevated PCT levels before surgery. On day one after the procedure PCT was elevated in those patients who in their further postoperative course developed complications. Patients without PCT elevation after open heart surgery had an uncomplicated recovery. Under the conditions of cardiogenic shock as well as the use of extracorporeal circulation, PCT is able to identify bacterial and fungal infections. It is helpful in evaluating the transplantability of patients on VADs. PCT seams to be unaffected by the use of extracorporeal circulatory circuits. However, a substantial number of patients exhibit PCT increase after ECC, and the PCT level has some prognostic value. The increase of PCT may be due to intestinal malperfusion.

Clinical Research in Cardiology, Apr 1, 2009

Purpose We compared early results of homograft aortic root replacement (ARR) in native (NVE) and ... more Purpose We compared early results of homograft aortic root replacement (ARR) in native (NVE) and prosthetic (PVE) aortic valve endocarditis in order to identify predictors for early mortality (\30 days). Methods Between 05/1986 and 12/2007, 1,163 endocarditis patients were operated upon. Of these, 221 patients (n = 185 men, median age 55 years) underwent homograft ARR due to 99 cases of NVE (45%) and 122 of PVE (55%) aortic root endocarditis. Demographics, clinical differences, survival rates and predictors of early mortality were analyzed. Follow-up (mean 5.2 ± 0.4 years, maximum 18.4 years) was completed in 96.8% with a total of 1,127 patient years. Results Main causes of the 47 (21.2%) early deaths were septic multiorgan failure in 23 (48.9%) and myocardial failure in 10 (21.3%) patients with a significantly better survival for NVE than for PVE patients (patients = 0.029). The highest ORs were found in the univariate analysis for preoperative development of septic shock (OR 14.28), preoperative necessity of ventilation (OR 7.08), high doses of catecholamines (OR 5.60), severe aortic root destruction (OR 5.12), emergency operation (OR 4.25) and persistent fever despite antibiotic treatment (OR 4.11). Multivariate analysis showed that preoperative ventilation (OR 5.43), persistent fever under antibiotic treatment (OR 2.84) and prosthetic endocarditis (OR 2.32) were independent risk factors for early mortality.

Thorac Cardiovasc Surg, 2010

Circulation, Nov 22, 2011

American Journal of Transplantation

The Thoracic and Cardiovascular Surgeon, 2010

The Journal of Thoracic and Cardiovascular Surgery, 2010

patient, it is preferable to avoid any unnecessary prolongation of the procedure. Finally, a pulm... more patient, it is preferable to avoid any unnecessary prolongation of the procedure. Finally, a pulmonary homograft is used to produce least turbulence, and these valves are considered the best substitute for the pulmonary valves.

The Journal of Heart and Lung Transplantation, 2004

Background: Procalcitonin (PCT) has been established as a marker for infectious inflammation with... more Background: Procalcitonin (PCT) has been established as a marker for infectious inflammation with systemic reactions and/or organ dysfunction. Several studies reported a strong correlation between high PCT levels and the risk of mortality in inflammatory conditions. We previously identified PCT as a predictor of early graft-failurerelated mortality after HTx . Now for the first time we evaluated PCT and Sequential Organ Failur Assessment (SOFA) score as prognostic markers in the early postoperative period after heart (HTx) and lung (LTx) transplantation. Methods: In a prospective study, blood was collected daily from 100 consecutive patients (age 47 Ϯ 13 years) for up to 28 days following HTx (n ϭ 73) and LTx (n ϭ 27). PCT serum concentrations were measured by immunoluminometry. In addition, C-reactive protein (CRP) was measured and WBC counts performed. To characterize the severity of illness the SOFA score was calculated in modified form. Results: From the 1 st until the 28 th postoperative day (POD) PCT levels were significantly higher in non-survivors than in survivors, whereas only CRP levels from the 7 th POD and WBC counts from 5 th POD were significantly higher in non-survivors. Areas under the receiver operating characteristic curve (ROC-AUC) for risk of mortality on the 1 st POD was 0.74 for PCT and increased continuously thereafter, compared to 0.47 for CRP and 0.48 for WBC counts on the 1 st POD. A PCT value of Ͼ2 ng/mL on the 7 th POD as a predictor for mortality had a specificity of 65.8% and sensitivity of 75%. Modified SOFA score showed the best results (ROC-AUC: on the 1 st POD 0.83 and from the 3 rd POD on Ͼ 0.9) Conclusions: In comparison to CRP and WBC counts, PCT and SOFA score were identified as the best predictors of mortality in patients after HTx and LTx. Calculation of SOFA score and PCT measurements in the early postoperative period after HTx and LTx may therefore be helpful in early therapeutic decision making, by identifying patients at high risk of mortality.

The Journal of Heart and Lung Transplantation, 2001

Background: Infections are known as a primary factor leading to morbidity and mortality in transp... more Background: Infections are known as a primary factor leading to morbidity and mortality in transplant recipients. The differentiation between sepsis/severe sepsis and systemic inflammatory reactions induced by operative trauma or by acute rejection is of great importance in the decision-making and timing of an adequate therapy. In addition immunosuppression makes the diagnosis of infection more difficult. Recently, procalcitonin (PCT) has been identified as a biological marker for sepsis/severe sepsis. The kinetics and the diagnostic value of PCT after transplantation of intrathoracic organs were prospectively evaluated. Methods: Blood was collected daily from 72 consecutive patients (age 46 Ϯ 13 years) for up to 38 days following heart (n ϭ 50), lung (n ϭ 19) and heart-lung (n ϭ 3) transplantation. PCT serum concentrations were measured by immunoluminometry. In addition, C-reactive protein (CRP) was measured. Cytoimmunological monitoring (CIM) and WBC counts were also performed. Results: The PCT levels increased significantly to reach a maximum on the 1st postoperative day (median 4.2, range 0.4-24.7 g/l) and decreased continuously thereafter in the absence of infection (pϽ0.001, n ϭ 38). In patients with perioperative infection episodes (n ϭ 21) the PCT levels, but not the CRP, levels were significantly higher than in those without infection (PCT: p Ͻ0.001, CRP: p Ͼ0.5). The persistence of high PCT levels thereafter closely correlated with the development of sepsis and or severe sepsis (n ϭ 13). In 15 patients 17 episodes of acute rejection were observed. PCT levels did not significantly increase during these episodes (pϾ0.8). The PCT levels are not influenced by the immunosuppression. Conclusion: Considering the postoperative kinetics of ProCT levels, ProCT measurements increase the accuracy of the diagnosis of sepsis/severe sepsis following transplantation of intrathoracic organs. As a biological marker PCT has advantages over established parameters in this situation.

The Journal of Heart and Lung Transplantation, 2009

The SOFA has an increasing role in the prediction of mortality and morbidity in cardiac surgical ... more The SOFA has an increasing role in the prediction of mortality and morbidity in cardiac surgical patients and before VAD therapy (1,2). As patients after HTx receive inotropes early postoperatively due to the pathophysiology of heart transplantation, identifying patients at high risk of mortality according to the use of catecholamines may be difficult. We evaluated the application of SOFA in prediction of 30-day mortality and morbidity in this setting. Methods and Materials: We retrospectively studied 126 consecutive heart transplant recipients (age: median 47, 12-70 years). The SOFA was calculated postoperatively and daily until intensive care unit (ICU) discharge or for a maximum of 7 days. C-reactive protein (CRP) values and white blood cell count (WBC) were reviewed. Lengths of ICU stay and 30-day mortality were assessed. Results: From the 1st until the 7th postoperative day (POD) only SOFA values, not CRP or WBC counts, were significantly higher in non-survivors (12.5%) than in survivors (Mann-Whitney test: p Ͻ0.01). For SOFA area under the receiver operating characteristic curve (ROC-AUC) for risk of 30-day mortality at ICU admission was 0.90 (95% CI 0.83 to 0.98). The highest value (0.94, 95% CI 0.88 to 0.99) was reached on the 4th POD. In survivors the maximum of SOFA, but not of CRP or WBC counts, correlated significantly with the length of ICU stay (p Ͻ 0.01). The main organ dysfunction responsible for the higher SOFA in non-survivors was renal dysfunction, followed by thrombocytopenia and respiratory dysfunction. Conclusions: Although patients after HTx need catecholamines in the early postoperative period, SOFA can be used to grade the severity of morbidity and to identify the risk of 30-day mortality. Renal function and thrombocytopenia are to be focused on in this condition. As an independent score, SOFA is therefore helpful in early therapeutic decision making and resource planning in heart transplanted patients.

Journal of Clinical Oncology, 2008

Journal of Thoracic and Cardiovascular Surgery, 2010

Solitary fibrous tumor (SFT) of the mediastinum occurs most commonly in the visceral and parietal... more Solitary fibrous tumor (SFT) of the mediastinum occurs most commonly in the visceral and parietal pleura; it is extremely rare for it to affect cardiac structures. We report, for the first time, a case of mediastinal SFT with an unusual vascular supply from the coronary arteries and an unusual location. The tumor was diagnosed 34 months after aortic valve replacement and revascularization of the left anterior descending coronary artery with the left internal thoracic artery (ITA). It was completely resected, and 16 months later, there have been no local or distant recurrences.

Clinical Research in Cardiology, 2009

Circulation, 2001

Background-To date, donor-specific markers to predict outcome after heart transplantation (HTx) a... more Background-To date, donor-specific markers to predict outcome after heart transplantation (HTx) are unknown.

The Annals of Thoracic Surgery, 2009

chambers. The two discs of the device are asymmetrical in size and will result in the deployment ... more chambers. The two discs of the device are asymmetrical in size and will result in the deployment of the larger disc in the pseudoaneurysm, which may injure the wall of the sac. For these reasons, we chose the Amplatzer muscular ventricular septal defect occluder device, because of two equal sized discs. It is essential that the disc at the aortic end should not impinge on the coronary ostia. We showed the feasibility of this procedure from both femoral and brachial routes. Both our patients have had good immediate-term and short-term outcomes.

ASAIO Journal, 2010

Mechanical circulatory support (MCS) is valuable in saving the lives of patients with severe card... more Mechanical circulatory support (MCS) is valuable in saving the lives of patients with severe cardiogenic shock. However, their survival is limited if multiorgan failure (MOF) proves to be irreversible. Although ventricular assist devices (VADs) have been shown to reverse end-organ failure in some patients, the pathophysiological mechanisms of end-organ failure and its regression are not fully understood, and clinical markers and thresholds for the &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;point of no return&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; are lacking. We investigated predictors of 30-day survival in patients supported with a biventricular assist device (BVAD). We studied 157 patients implanted with a Berlin Heart EXCOR BVAD between 1987 and 2006. Children younger than 10 years and cases with postcardiotomy syndrome and transplant failure were excluded from the analysis as well as patients with technical or bleeding problems requiring rethoracotomy. In total, 69 clinical, hemodynamic, echocardiographic, and laboratory parameters were evaluated. Most of the patients suffered from ischemic cardiomyopathy or acute myocardial infarction. In addition, the preoperative multiple organ dysfunction syndrome (MODS) and the sequential organ failure assessment (SOFA) scores were calculated. The patients were divided into two groups regarding procedural success: group I-survival &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;30 days or heart transplantation or weaning from device (n = 105) and group II-death on system &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;30 days after surgery (n = 52). The 30-day procedural success rate was 67%. The patients in group I had higher systolic blood pressure (96.7 vs. 90.1 mm Hg, p = 0.027), lower serum creatinine (1.96 vs. 2.4 mg/dl, p = 0.001), and higher arterial pH (7.43 vs. 7.37, p = 0.02). The multivariate analysis recognized age, body temperature, systolic blood pressure, MODS score, and higher arterial pH as significant predictors for 30-day mortality. Standard markers for severity of cardiogenic shock and MOF do not predict survival on BVAD. As expected, older patients are at higher risk for death on BVAD. Acidosis and high MODS score predict unfavorable outcome. However, the prediction of clinical outcome in patients in severe cardiogenic shock supported by BVAD is possible in extreme situations only.