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Dive into the research topics where Vladimir Sojak is active.

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Featured researches published by Vladimir Sojak.


The Annals of Thoracic Surgery | 2008

Cardiac Resynchronization Therapy for the Failing Fontan Patient

Vladimir Sojak; Uros Mazic; Maja Cesen; Jürgen Schrader; Nenad Danojevic

Myocardial dysfunction is the leading cause of death in single-ventricle patients. Heart transplantation has traditionally been reserved for Fontan patients with end-stage myocardial dysfunction. Cardiac resynchronization therapy with multisite pacing was found to improve the myocardial performance in Fontan patients in acute postoperative settings; however, its role is unclear in chronic Fontan patients with progressive myocardial dysfunction. We present a case in which cardiac resynchronization therapy improved both hemodynamics and clinical condition in a Fontan patient with advanced myocardial dysfunction.


European Journal of Cardio-Thoracic Surgery | 2000

Results of modified Norwood's operation for hypoplastic left heart syndrome

Viktor Hraska; Matej Nosal; Pavol Sýkora; Vladimir Sojak; Michal Šagát; Pavol Kunovský

OBJECTIVE The aim of the study was to analyze intermediate results of treatment of the hypoplastic left heart syndrome based on selective indication criteria. METHODS Between February 1997 and May 1999 38 patients with hypoplastic left heart syndrome (n=35), or with functional variant of hypoplastic left heart syndrome (n=3) were admitted to our department. Contraindications for surgery were birth weight <2500 g, diameter of ascending aorta <2 mm, severe tricuspid regurgitation persisting after initial stabilization, pulmonary regurgitation more than mild, dysfunction of the systemic right ventricle and failure to effectively resuscitate circulation before surgery. RESULTS Based on these criteria surgery was not indicated in 17 patients. Twenty-one infants were operated on by modified Norwoods procedure using only autologous great vessel tissue for reconstruction of systemic outflow. Overall hospital mortality was 14% (three patients). Eighteen survivors (86%) were discharged with well-balanced circulation. There was one late death (5%). Thirteen patients had already undergone the second stage (bi-directional Glenn) with no death. The mean follow-up was 13. 2+/-9.1 months (range 4-32 months). Considering both early and late events the probability of survival for the whole group (n=21) from the time of surgery was 86% at 1 month, 80% at 12 months, and it remained unchanged at 18 and 24 months of follow-up. CONCLUSIONS Only a limited number of European countries offer surgical treatment of hypoplastic left heart syndrome. Promising intermediate results (80% survival rate after stage I and II) achieved at our department do not only reflect overcoming the learning curve but also a selective approach to indication for surgery as well. In a country with limited resources selective approach to the patients with hypoplastic left heart syndrome is justified.


European Journal of Cardio-Thoracic Surgery | 2016

A single-centre 37-year experience with reoperation after primary repair of atrioventricular septal defect

Vladimir Sojak; Marlotte Kooij; Aria Yazdanbakhsh; Dave R. Koolbergen; Eline F. Bruggemans; Mark G. Hazekamp

OBJECTIVES To evaluate our experience with patients reoperated after primary repair of atrioventricular septal defect (AVSD) and identify predictors of poor outcome. METHODS Between 1976 and 2014, 69 patients were reoperated after primary repair of partial (n = 28), intermediate (n = 15) or complete (n = 26) AVSD. RESULTS Median age at first reoperation was 62.4 (range, 1.6-845) months, median interval to first reoperation was 22.3 (range, 0.2-598) months. Main indications for first reoperation included left atrioventricular valve (LAVV) pathology (66%), residual septal defect (19%) and left ventricle outflow tract obstruction (LVOTO; 4%). Procedures to address LAVV pathology included various valvuloplasties in 47 (77%) patients and valve replacement in 14 (23%) patients. A second, third, fourth and fifth reoperation was required in 27, 12, 4 and 1 patient, respectively. Most common procedures were LAVV replacement (LAVVR), LVOTO relief, pacemaker implantation and right atrioventricular valve procedure. Freedom from reoperation after LAVV valvuloplasty (LAVVP) was 84 and 62% at 1 and 10 years, respectively. There were 10 early and 4 late deaths. Estimated overall survival at 1, 5 and 10 years was 87, 83 and 83%, respectively. Double orifice LAVV (DOLAVV) was a risk factor for in-hospital and overall mortality [odds ratio (OR) = 14.5; 95% confidence interval (CI) = 1.2-178.7; P = 0.037 and hazard ratio (HR) = 6.8; 95% CI = 1.5-31.7; P = 0.015, respectively]. Patients with LAVVP and LAVVR differed significantly in overall survival (P = 0.014). At the last follow-up (median, 9.8; range, 0-34 years), 84% survivors were in New York Heart Association Class I or II. CONCLUSIONS Many patients reoperated after primary AVSD repair needed surgical reintervention. LAVV pathology was the most common indication for reoperation. DOLAVV was a risk factor for mortality. Particular AVSD type did not appear to be a risk factor for mortality or LAVVP failure. There is some evidence for the close relationship between LAVV pathology and LVOTO in subjects undergoing reoperation after primary AVSD repair as some patients with initial LAVV problems needed LVOTO repair later on and vice versa.


European Journal of Cardio-Thoracic Surgery | 2012

Mid-term results of bidirectional cavopulmonary anastomosis and hemi-Mustard procedure in anatomical correction of congenitally corrected transposition of the great arteries †

Vladimir Sojak; Irene M. Kuipers; Dave R. Koolbergen; Marry Rijlaarsdam; Jaroslav Hruda; Nico A. Blom; Mark G. Hazekamp

OBJECTIVES The Senning or Mustard procedure combined with the arterial switch operation (ASO) (± VSD and no left ventricular (LV) outflow tract obstruction) or the Rastelli operation (VSD and LV outflow tract obstruction) has become the preferred strategy over conventional repair as it is thought to prevent long-term dysfunction of the right ventricle (RV). More recently, hemi-Mustard rerouting of blood from the inferior vena cava to the RV in combination with bidirectional cavopulmonary anastomosis (BCPA) has been adopted by some centres for potential benefits over the classic atrial switch procedure. The aim of this study was to analyse our experience with hemi-Mustard and BCPA as part of an anatomical repair of congenitally corrected transposition of the great arteries (CCTGA) in selected patients. METHODS Between 2004 and 2011, eight patients underwent hemi-Mustard/BCPA with the Rastelli operation (n = 6) or ASO (n = 2). The median age was 2.9 (range: 1.2-9.1) years. Positional anomalies were present in 75% of the patients. Both patients with ASO had dysplastic and insufficient tricuspid valves. In the Rastelli group, four patients had previously received shunts followed by BCPA in one patient. In the ASO group, both patients underwent pulmonary artery banding initially. RESULTS There was one in-hospital death and no late mortality. Two patients received a pacemaker. One patient from the Rastelli group required conduit change 6 years later. At the mean follow-up of 4.5 years, six and one patients are in NYHA classes I and II, respectively; six patients showed good biventricular function, while one had LV dysfunction. Systemic venous obstruction and sinus node dysfunction were not observed, and BCPA was functioning well in all patients. CONCLUSIONS Hemi-Mustard/BCPA is useful in anatomical repair of CCTGA in selected patients. When compared with the classic atrial switch operation, it is technically easier which makes it especially helpful in atrio-apical discordance; it unloads an RV with limited size or function, and avoids complications related to the upper limb of the classic atrial switch procedure. Mid-term results of this approach are favourable. Further follow-up is needed to prove long-term benefits.


Multimedia Manual of Cardiothoracic Surgery | 2015

Partial and intermediate atrioventricular septal defects without major associated cardiac anomalies

Panagiotis Sfyridis; Vladimir Sojak; Mark G. Hazekamp

Partial and intermediate atrioventricular septal defects (p-i AVSDs) constitute approximately 20-40% of all AVSDs. Children with p-i AVSDs are usually asymptomatic and typically undergo surgery at the preschool age or earlier if the signs of heart failure have developed. Surgical treatment for repair of p-i AVSDs has been successful for more than 60 years and is mainly directed towards closing septal defects, and maintaining or creating competent, non-stenotic left and/or right atrioventricular valves. By most measures, the outcomes of surgical management of p-i AVSDs have improved over the last 5 decades. In spite of significantly reduced mortality, the need for reoperation and long-term morbidity remains an issue in some patients from this population. The purpose of this article is to review current options and outcomes concerning the surgical management of the p-AVSD and i-AVSD variants without major associated cardiac malformations.


Multimedia Manual of Cardiothoracic Surgery | 2012

Surgery for truncus arteriosus

Vladimir Sojak; Julio Lugo; Dave R. Koolbergen; Mark G. Hazekamp

Truncus arteriosus (TA) is a congenital heart defect in which a common arterial trunk supplies systemic, pulmonary and coronary circulation. Associated cardiac anomalies are common. Without surgical treatment, most patients die within infancy. Various operative techniques have evolved over the past 50 years. More recently, many centres have adopted primary repair in the neonatal period or early infancy. The objective of this paper is to describe anatomy, diagnosis, natural history and the technique of operation of TA.


World Journal for Pediatric and Congenital Heart Surgery | 2010

Simultaneous Repair of Supravalvar Aortic and Supravalvar Pulmonary Stenosis Using the 3-Patch Technique

Vladimir Sojak; Dave R. Koolbergen; Luc Filippini; Mark G. Hazekamp

Patients with Williams-Beuren syndrome may have bilateral outflow tract obstruction. We report a simultaneous repair of supravalvar aortic and supravalvar pulmonary stenosis using the 3-patch technique.


World Journal for Pediatric and Congenital Heart Surgery | 2018

Long-Term Outcome of Direct Relief of Subaortic Stenosis in Single Ventricle Patients

Friso M. Rijnberg; Vladimir Sojak; Nico A. Blom; Mark G. Hazekamp

Background: Single ventricle patients with unrestrictive pulmonary blood flow and (potential) subaortic stenosis are challenging to manage and optimal surgical strategy is unknown. Direct relief of subaortic stenosis by enlargement of the ventricular septal defect and/or subaortic chamber has generally been replaced by a Damus-Kaye-Stansel or Norwood procedure due to concerns of iatrogenic heart block, reobstruction, or ventricular dysfunction. Studies reporting long-term outcome after the direct approach are limited. The aim of our study was to describe and analyze our experience with direct relief of subaortic stenosis in single ventricle patients. Methods: Demographic data, characteristics, and pre-operative, operative and outcome details were collected for children undergoing direct relief of subaortic stenosis between 1989 and 2016. Results: Twenty-three patients (median age: 7.4 months, range: 10 days to 5.5 years) underwent direct relief of subaortic stenosis. Complete follow-up was available for all patients (median: 15.6 years, range: 34 days to 26.3 years). Seven (30%) patients had recurrence of subaortic stenosis. One (4%) patient developed complete heart block and one patient developed moderate ventricular dysfunction. Five (50%) patients developed a (pseudo)aneurysm at site of the patch and ventriculotomy. There were two perioperative deaths. Eighty-six percent of patients underwent a successful Fontan procedure. Conclusions: Direct relief of subaortic stenosis is associated with a substantial risk of reobstruction and patch (pseudo)aneurysm formation. However, risk of heart block is low and long-term outcome is good with the majority of patients reaching Fontan completion. In our opinion, the direct approach appears to be a good and relatively simple procedure in selected cases for the treatment of subaortic stenosis.


European Journal of Cardio-Thoracic Surgery | 2018

Aortic coarctation repair through left thoracotomy: results in the modern era†

Emile S. Farag; Jolanda Kluin; Frederiek de Heer; Yunus Ahmed; Vladimir Sojak; David R. Koolbergen; Nico A. Blom; Bas A.J.M. de Mol; Arend D.J. ten Harkel; Mark G. Hazekamp

OBJECTIVES Surgical repair of coarctation of the aorta (CoA) is often possible through left thoracotomy and without the use of cardiopulmonary bypass. Recent studies reporting the outcome after CoA repair through left thoracotomy are limited. Therefore, the aim of this study is to evaluate the results of CoA repair through left thoracotomy in children who were operated on in our centre over the past 21 years. METHODS From January 1995 to December 2016, 292 patients younger than 18 years underwent primary CoA repair through left thoracotomy at our 2 institutions. Peri- and postoperative data and follow-up data collected from our hospital and the referring hospitals were retrospectively reviewed. RESULTS Median age at operation was 64 days (range 2 days-17 years). Most patients underwent the resection of the CoA followed by an (extended) end-to-end anastomosis (93%). Six patients died perioperatively and 2 more patients died during the follow-up, of which 7 patients had other major comorbidities. Actuarial survival was 97% at 5 years, 96% at 10 years and 96% at 15 years. Second arch interventions due to recoarctation were performed in 9.9% (n = 29) of patients, consisting of balloon dilatation in all but 2 patients. Recoarctation occurred significantly more often after initial repair in the neonatal period (21%) and could occur as late as 14 years after initial surgery. There were 7 re-recoarctations, and 14% of patients were on hypertensive medication during the follow-up. CONCLUSIONS Repair of CoA through left thoracotomy is a safe procedure with low rates of mortality. The long-term follow-up is necessary due to the significant risk of recoarctation requiring reintervention.


European Journal of Cardio-Thoracic Surgery | 2016

Reoperation for right ventricular outflow tract obstruction after arterial switch operation for transposition of the great arteries and aortic arch obstruction.

Regina Bökenkamp; Elizabeth Aguilar; Roel L.F. van der Palen; Vladimir Sojak; Eline F. Bruggemans; Jaroslav Hruda; Irene M. Kuipers; Mark G. Hazekamp

OBJECTIVES Right ventricular outflow tract obstruction (RVOTO) is one of the reasons for late reinterventions after repair of transposition of the great arteries (TGA) with aortic arch obstruction (AAO). The aim of the present study was to identify predictors of reoperation for RVOTO in patients who underwent arterial switch operation (ASO) and arch repair for TGA or Taussig-Bing anomaly with AAO. METHODS Between 1977 and 2015, 45 patients [TGA/intact ventricular septum (IVS) 5, TGA/ventricular septal defect (VSD) 13, Taussig-Bing 27] with coarctation (21), arch hypoplasia (5), coarctation and hypoplasia (12) and aortic arch interruption (7) underwent ASO and arch repair. The median age at the ASO was 19 days (range, 1 day to 12.7 years). AAO was repaired concomitantly with ASO in 36 patients. Operation reports and 2D-echocardiographic data were retrospectively reviewed to determine the following parameters: position of the great arteries, coronary artery anatomy, and diameters of RVOT, aortic annulus, aortic sinotubular-junction, pulmonary annulus and transverse aortic arch previous to ASO. The median follow-up time was 6 years (range, 0-30 years). Four patients were lost to follow-up; reliable echo data were available in 24 subjects. Cox proportional hazard models were performed to examine predictors of reoperation for RVOTO. RESULTS Thirty-day mortality rate after ASO was 13% (n = 6), and late mortality rate 9% (n = 4). Ten patients (TGA/VSD 2, Taussig-Bing 8) had 14 reoperations for RVOTO. One patient died after reoperation. Taussig-Bing anomaly was a significant predictor of reoperation for RVOTO [hazard ratio (HR) = 5.5, 95% confidence interval (CI) = 1.15-26.38, P = 0.033]. Higher preoperative aortic annulus Z-score significantly decreased the reoperation risk (HR = 0.6, 95% CI = 0.42-0.93, P = 0.020). In reoperated patients, the mean gradient across the RVOT reduced from 84 ± 12.2 mmHg prior to reoperation to 15.29 ± 13.70 mmHg at latest follow-up. CONCLUSIONS Taussig-Bing anomaly and smaller preoperative aortic annulus diameter (Z-score) were significant predictors of reoperation for RVOTO in patients after ASO for TGA or Taussig-Bing anomaly with AAO. In Taussig-Bing hearts, the more complex anatomy often necessitates modifications of the operation technique, sometimes precluding RVOT relief at primary ASO. During follow-up, the possibility of recurrent RVOTO should always be considered in this specific patient population. Yet, in case of a reoperation for RVOTO, the surgical relief is in general effective.

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Mark G. Hazekamp

Leiden University Medical Center

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Dave R. Koolbergen

Leiden University Medical Center

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Eline F. Bruggemans

Leiden University Medical Center

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Irene M. Kuipers

Boston Children's Hospital

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David R. Koolbergen

Leiden University Medical Center

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Jaroslav Hruda

VU University Medical Center

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Marlotte Kooij

Leiden University Medical Center

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Nico A. Blom

Leiden University Medical Center

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