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Miralem Pasic

Publications and source records attributed to Miralem Pasic.

At least 19 recordsLinked to original sources

Impact of heparin-induced thrombocytopenia on outcome in patients with ventricular assist device support: single-institution experience in 358 consecutive patients.

BACKGROUND: Cardiac surgical patients are at an approximate 1% to 2% risk of experiencing heparin-induced thrombocytopenia (HIT), a severe immune-mediated disease that is associated with thromboembolic events. We assessed the occurrence of this disease and its influence on clinical outcome in patients after implantation of a ventricular assist device (VAD). METHODS: This retrospective analysis assessed data from our adult patient VAD program between the years 2000 and 2005. Patients were divided into three groups: those without confirmed HIT ((non)HIT), those in whom the diagnosis of HIT was made before VAD implantation (HIT(pre)), and those who experienced HIT after VAD implantation (HIT(post)). End points assessed were procedural success, as defined by discharge from hospital or transplantation or recovery of the failing heart, as opposed to death before procedural success was achieved. RESULTS: The data of 358 consecutive patients were analyzed. There were 330 (non)HIT patients (91.6%), 15 HIT(pre) patients (4.5%), and 13 HIT(post) patients (3.9%). Procedural success was observed in 50% of (non)HIT patients, 67% of HIT(pre) patients, and 31% of HIT(post) patients. CONCLUSIONS: Heparin-induced thrombocytopenia is a frequent complication in VAD patients and is associated with detrimental outcome when occurring after implantation. Preoperative diagnosis of HIT and the implementation of alternative anticoagulation procedures appears to be associated with better results. Early detection of HIT antibodies before or shortly after VAD implantation and immediate implementation of an alternative anticoagulation regimen may be a strategy to improve outcome.

Adult↗

Patients supported for over 4 years with left ventricular assist devices.

Ventricular assist device implantation has become an established therapy in adults and children for bridging to heart transplantation or to aid myocardial recovery. Recently, implantation of left ventricular assist devices as definitive therapy has been recognized as a better option than pharmacological treatment in patients who are not candidates for heart transplantation. This study presents our institution's experience with five patients successfully supported by two different left ventricular assist devices for over 4 years. This unique experience shows that left ventricular assist device support can be extended beyond 4 years with good quality of life and low risk, making it a good alternative for non-transplant candidates.

Adult↗

Homograft reconstruction of the aortic root for endocarditis with periannular abscess: a 17-year study.

OBJECTIVE: The study was conducted to evaluate the long-term results of homograft reconstruction of the left ventricular outflow tract with a cryopreserved aortic homograft in the presence of aortic root abscess associated with a biofilm bacterial infection. METHODS: Between January 1987 and December 2003, 161 patients with aortic root abscess underwent freehand aortic valve (FAVR, N = 78) and aortic root replacement (ARR, N = 83) with an antibiotic treated cryopreserved aortic homograft. Their mean age was 53.1+/-15.6 years. Endocarditis of the native valve was found in 80 patients and of the prosthetic valve in 81; of the prosthetic valves 49 (60.5%) were mechanical and 32 (39%) bioprosthetic. Aortic ventricular discontinuity was found in 83 patients. The common responsible microorganisms were the biofilm bacteria: Staphylococcus (S. epidermidis: 34, S. aureus: 13) in 47 patients followed by Enterococcus in 23 and Streptococcus in 39. Surgery was urgent in 80 patients and emergent in 81, of whom 44 were in cardiogenic shock. Follow-up totaled 810.8 patient-years (mean: 5.0+/-4.3 years) and was 100% complete. RESULTS: Operative mortality was 9.3% for elective/urgent and 14.3% for emergency surgery. A total of 7.3% patients died after hospital discharge during the 17-year follow-up period. The actuarial patient survival at 17 years was 70.4+/-3.6%. Early and late residual/recurrent infections and paravalvular leaks occurred in 4.3 and 2.5%, respectively. Reoperations were carried out in 30 patients, 11 for residual/recurrent infection and paravalvular leaks. Twenty-one patients with FAVR and 9 with ARR techniques underwent reoperation. Early reoperation rate was 4.3%. The actuarial freedom from residual/recurrent infection and paravalvular leaks was 91.6+/-2.4%. Actuarial freedom from reoperation at 17 years was 75+/-3.7%. It was 82.9+/-5.5% for ARR and 63.5+/-6.7% for AAVR technique. The actuarial freedom from structural valve deterioration (SVD) at 17 years was 98.6+/-0.4.% at a rate of %/patient-year. CONCLUSIONS: Radical debridement of the infected aortic root and homograft ARR offer a low recurrent infection rate and an overall low valve-related morbidity and mortality for up to 17 years. The antibiotic permeable cryopreserved homograft has proven to be resistant to biofilm bacterial infection.

Abscess↗

Aortic root abscess and secondary infective mitral valve disease: results of surgical endocarditis treatment.

OBJECTIVE: Mortality in active infective endocarditis (AIE) is substantial and reinfection can strongly influence outcome. Assessment of factors influencing mortality is important. We studied 108 (33%) patients suffering from root abscess out of a total of 327 AIE patients admitted to the Deutsches Herzzentrum Berlin for surgical treatment between 1996 and 2003. Among them were 53 (25.5% of all patients) who were diagnosed as having secondary infective mitral valve disease (SMVD). Mean age was 53+/-14.2 years; there were 37 men and 16 women. METHODS: Risk factors were assessed on the basis of clinical, hemodynamic, echocardiographic and surgical information. Mean follow-up was 325+/-251 days with complete echocardiographic examination performed in patients with double valve surgery. The differences between groups were analyzed using Student's t-test. Multivariate analysis for the whole group suffering from abscess was performed to identify independent factors influencing mortality. RESULTS: In 19 (35.8%) patients suffering from SMVD mitral valve reconstruction was undertaken and mitral valve replacement was performed in 34 (64.2%) patients. There were 27 patients treated with a Shelhigh prosthesis: 18 with double valve replacement (both Shelhigh) and nine with an aortic Shelhigh prosthesis and concomitant mitral valve reconstruction. Homografts were used in 17 patients, with mitral reconstruction in 10 and a stented mitral prosthesis in seven. In nine cases two stented valve prostheses were used. The calculated mean Doppler gradient for homografts and Shelhigh in aortic position was 12 (+/-5.7) and 15 (+/-4.6), respectively (NS). The following predisposing factors for mortality were assessed: severe damage of aortic annulus (OR 4.65, CI 1.22-17.1, P=0.0159); septic shock (OR 3.44, CI 0.85-13.9, P=0.07) and poor ejection fraction (<40%), and dilated LV. CONCLUSIONS: Excessive mortality reaching 29% was noted in patients suffering from AIE with aortic ring abscess and SMVD requiring double valve surgery. Double valve surgery with semi-stented Dacron-free valve prostheses is associated with a low rate of reinfection and good function of the implants. The most potent independent risk factors for death were septic shock and severe aortic root destruction.

Abscess↗

Permanent mechanical circulatory support in patients of advanced age.

OBJECTIVE: This study details our initial results of long-term left ventricular assist device (LVAD) support in patients suffering from catecholamine-dependent end-stage heart failure or cardiogenic shock with age above 65 years or age above 60 and contraindications to cardiac transplantation. METHODS: Between September 2000 and July 2002, 27 patients received implantation of left ventricular assist devices (Micromed DeBakey (n=15), Berlin Heart Excor (n=6), Arrow Lion Heart (n=4) and Novacor N100 (n=2)). The mean age of this group was 66.2+/-4.1 (60-77) years. The patients presented with the following features by the time of LVAD implantation: failure of weaning from inotropic support (78%), either profound cardiogenic shock (37%) or instable hemodynamic status (22%), high-dose inotropic (52%) or intraaortic balloon pump support (11%), dialysis (15%), artificial ventilation (15%), and at least one previous cardiac procedure (44%). RESULTS: The cumulative survival rate for the whole group was 63% at 30 days, 30% at 180 days, and 22% at 2 years. The presence of preoperative cardiogenic shock was associated with a higher perioperative mortality rate. Late complications (n=7) included replacement of two thrombosed DeBakey LVADs and five late deaths secondary to thrombembolism/intracranial hemorrhage (DeBakey LVAD, n=3) or septicemia (n=2). As of May 15, 2003, six patients remain on LVAD support for an average of 653 (339-953) days, three patients now for more than 2 years. Ten patients were discharged home to spend 73% of their life span on out-of-hospital long-term LVAD support. CONCLUSION: This study reports the first single-center experience of permanent LVAD support in patients of advanced age. For this initial experience, many patients with critical circulatory status and previous cardiac operations were included and a high postoperative mortality rate was encountered among them. Older age and associated multimorbidity are the key determinants rendering the conditions of LVAD therapy for this patient cohort to be different from the bridge-to-transplant experience. The LVADs employed in this study showed different capabilities with regard to long-term support. Our experience shows that permanent mechanical circulatory support does have the potential to evolve as a treatment option in selected elderly patients with end-stage heart failure.

Aged↗

First experiences with a novel magnetically suspended axial flow left ventricular assist device.

UNLABELLED: Axial flow pumps have gained increased acceptance since their first clinical use in 1998. The present report summarizes the clinical experience with patients treated for severe cardiogenic shock for the first time with a newly developed axial flow pump with magnetically levitated bearings. MATERIAL AND METHODS: The axial flow pump Incor was implanted in 24 patients between June 2002 and June 2003. All except one patient were men. In 16 patients dilative cardiomyopathy, in seven ischemic and in one restrictive cardiomypathy had been diagnosed. All patients presented with catecholamine-dependent end-stage heart failure, seven of them were on an artificial ventilator and three were dependent on intraaortic balloon pump support. All patients suffered from organ dysfunction resulting from low cardiac output. RESULTS: There were no perioperative deaths. The 30-day mortality rate was 8% (n = 2); 79% ( n = 19) of patients reached a condition to be discharged home. The cumulative time on the device is 6.9 years; the longest individual time up to July 1, 2003 is 12.6 months. There were no structural defects or failures of the system. In one case the controller had to be exchanged because of intermittent malfunction. Cardiac output ranged between 4 and 6 l in all instances and there were no cases of infection of the drive-line or the system. Hemolysis was present initially but was not detectable in the later course. There were three instances of transient ischemic attacks. Two patients developed late cardiac tamponade with re-opening of the chest after 9 and 14 days. In one patient persistent gastrointestinal bleeding required re-hospitalization and transfusion therapy. Two patients were weaned from the device after 6 and 7 months of support, respectively. CONCLUSION: The preliminary clinical experience with Incor is promising. The flow is sufficient for recovery from multiorgan failure and the pump allows long-term hemolysis-free support. The concept of magnetically levitated bearings has proven to be durable and reliable. In the case that the heart may recover through unloading, weaning from the pump is possible.

Adult↗

Transcontinental transport of a patient with an AbioMed BVS 5000 BVAD.

In patients with severe cardiogenic shock requiring implantation of a short-term assist device transportation to a specialized heart center for further therapy may be necessary. We report the first successful transcontinental air transport (from Singapore to Berlin, Germany) of a patient with fulminating myocarditis requiring implantation of a biventricular assist device.

Air Ambulances↗

Factors influencing the results of double-valve surgery in patients with fulminant endocarditis: the importance of valve selection.

BACKGROUND: Extension of infection below the aortic valve is a serious complication, especially with mitral valve involvement. Mortality is substantial and reinfection can strongly influence outcome. PATIENTS: Of 327 surgical patients with active infective aortic valve endocarditis admitted to the Deutsches Herzzentrum Berlin for surgical treatment between December 1996 and December 2003, 108 had root abscess, and 53 (25.5%) had diagnoses of secondary infective mitral valve disease (SMVD). The mean age (+/-SD) was 53 +/- 14.2 years; there were 37 men and 16 women. METHODS: The secondary lesion on the mitral valve was classified as SMVD requiring double-valve surgery (DVS). This prospective clinical and echocardiographic study revealed 2 paths of infection extension into the mitral valve. In the DVS group, 38 patients (71.7%) had tissue metastatic lesions, and 15 patients (28.3%) had a jet lesion on the mitral valve. Most patients (42) with SMVD had an aortic ring abscess as the primary lesion. RESULTS: All patients with destructive endocarditic doublevalve disease received aortic and mitral valve surgery. In 19 cases (35.8%), mitral valve reconstruction was undertaken; in 4 cases, mitral valve replacement had to be carried out after attempted mitral valve reconstruction. Concomitant mitral valve replacement because of severe damage to the valvular and subvalvular apparatus was performed in 30 patients (56.6%). Other types of surgery performed in 11 cases (20.8%) were 8 closures of a septic ventricular septal defect and 3 closures of a fistula to the right ventricle or right atrium. Twenty-seven patients were treated with a Shelhigh prosthesis, 18 were treated with double-valve replacement (both Shelhigh), and 9 were treated with an aortic Shelhigh prosthesis and concomitant mitral valve reconstruction. Homografts were used in 17 patients, with mitral valve reconstruction carried out in 10 patients and a stented mitral prosthesis in 7. In 9 cases, 2 stented valve prostheses were used. There were 14 early (60 days) deaths (26.4%). Septic shock, severe annular and subannular destruction, and poor left ventricular function (end-diastolic dimension >65 mm, ejection fraction <40%) were the significant risk factors determined in the multivariate analysis. Function of Implants: Continuous and Color Doppler Investigation: Comparative studies of 2 different implants in the aortic position were performed late postoperatively (325 +/- 251 days) for homografts and the Shelhigh stentless prosthesis. The calculated instantaneous (maximal Doppler) gradient and the mean pressure gradient through the aortic implants were 19 +/- 10.4 mm Hg and 12 +/- 5.7 mm Hg, respectively, for the homografts and 24 +/- 8.4 mm Hg and 15 +/- 4.6 mm Hg, respectively, for the Shelhigh stentless prosthesis (not significantly different for the 2 groups). There was no mitral or aortic valve dysfunction. A trivial paravalvular leakage in the mitral position in 1 patient and a pseudoaneurysm of the left ventricular out- flow tract without leakage or valvular dysfunction in another were diagnosed by postoperative Doppler investigation. CONCLUSIONS: The mortality in patients with destructive endocarditis requiring DVS depends mostly on the patients' preoperative hemodynamic situation. The risk of reinfection can be minimized if valve substitutes are properly selected (homografts, Shelhigh No-React SuperStentless and No-React BioConduit in the aortic position, or Shelhigh BioMitral in the mitral position). Concomitant mitral valve reconstruction procedures do not increase the risk of mitral reinfection.

Endocarditis↗

Stentless aortic valves as an alternative to homografts for valve replacement in active infective endocarditis complicated by ring abscess.

BACKGROUND: The valve substitute of choice in active infective aortic valve endocarditis complicated by annulus abscess in our institution is the cryopreserved homograft. To avoid implantation of any prosthetic material, the Shelhigh No-React stentless valves and conduits may be considered an alternative when no suitable homograft is available. METHODS: Between March 1986 and January 2001, 452 homografts were implanted in the aortic position. From January 2000 to August 2001, 75 Shelhigh No-React prostheses were implanted at our institution. In 25 consecutive patients (study group) with aortic annulus abscess, urgent aortic valve replacement with the Shelhigh SuperStentless and Stentless Aortic Valve Conduit was undertaken. Patients (16 male, 9 female; age, 49 +/- 19 years) were studied with follow-up until March 2002. The control group comprised 68 consecutive historical patients (46 male, 22 female; age, 53 +/- 14.4 years) with similar disease treated between January 1997 and December 1999 in whom an aortic homograft was implanted. This group was also followed up until March 2002. Demographic data and preoperative characteristics of the patients were without significant differences. Patients were studied by echocardiography. RESULTS: Sixty-day mortality was 16% (11 patients) in the control group compared with 12% (3 patients) in the study group. Recurrent infection occurred in 4% in both groups. The instantaneous and mean Doppler gradients yielded no significant differences (19.4 +/- 10.4 mm Hg and 11.8 +/- 5.7 mm Hg versus 18.2 +/- 8.7 mm Hg and 10.9 +/- 5.3 mm Hg, respectively). The mean effective orifice area calculated from Doppler flow velocity for the stentless valve was 2.3 +/- 0.6 cm2. Preoperative evaluation of left ventricular dimensions and global left ventricular systolic function did not vary significantly between the two groups. However, postoperatively evaluated left ventricular end-diastolic diameter dimensions in the study group were significantly smaller than those in the control group (47.6 +/- 7.9 mm versus 56 +/- 9.5 mm; p = 0.05). Ejection fraction was similar in both groups (56.2% +/- 12.8% for the study [Shelhigh] and 52.6% +/- 16.8% for the control [homograft] group). CONCLUSIONS: Our experience with both the Shelhigh No-React SuperStentless and Stentless Aortic Valve Conduit in patients with native or prosthetic aortic valve endocarditis appears to demonstrate good results, similar to those of cryopreserved homografts. Ease of implantation and favorable effective orifice area and pressure gradients, as well as the No-React anticalcification treatment, are promising factors.

Abscess↗

New approach in treatment of acute cardiogenic shock requiring mechanical circulatory support.

In 12 patients with acute cardiogenic shock who required mechanical circulatory support a short-term Abiomed BVS 5000 extracorporeal assist device was implanted using the inflow and outflow cannulas of the BerlinHeart extracorporeal assist device. In 7 patients suitable for long-term support the Abiomed pumps were later exchanged for BerlinHeart pumps. This approach avoids the risks associated with repeat sternotomy and use of cardiopulmonary bypass and decreases the total costs of patient care.

Acute Disease↗

Cannulation of the right axillary artery for surgery of acute type A aortic dissection.

OBJECTIVE: The optimal choice of the arterial inflow site during operations for type A aortic dissection is not clearly defined. The aim of the prospective study was to identify whether cannulation of the right axillary artery instead of the femoral artery may improve the results of surgery for acute type A aortic dissection. METHODS: Seventy consecutive patients were operated on because of acute type A aortic dissection from January 2000 to February 2002. The only difference in surgical strategy was the site of arterial cannulation: the right axillary artery was used in 20 patients [axillary group] and the left femoral artery in 50 patients [femoral group]. All patients had aortic surgery with open distal anastomosis during deep hypothermic arrest and retrograde cerebral perfusion. The mean age was 58.7 +/- 12 years with a range from 28 to 88 years (axillary group, 56.6 +/- 13 years; femoral group, 59.4 +/- 12 years; P = 0.435). Preoperatively evident organ malperfusion was identified in five (25%) patients of the axillary group and in seven (14%) of the femoral group. RESULTS: There was no perioperative death. The hospital mortality rate was 5.0% for the axillary group and 22% for the femoral group (all patients, 17%). Major neurological complications occurred postoperatively in 5% of patients from the axillary group (one out of 20 patients) and in 8% of patients from the femoral group (four out of 50 patients) (all patients, 7%). CONCLUSION: Cannulation of the right axillary artery improved the outcome of surgery for acute type A aortic dissection. However, postoperative complications occurred after both axillary and femoral artery cannulation.

Acute Disease↗