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Marko I Turina

Publications and source records attributed to Marko I Turina.

At least 19 recordsLinked to original sources
PubMed2006

Geometric models of the aortic and pulmonary roots: suggestions for the Ross procedure.

OBJECTIVE: To discuss geometric factors, which may influence long-term results relating to homograft competence following the Ross procedure, we describe the 3D morphology of the pulmonary and aortic roots. MATERIALS: Measurements were made on 25 human aortic and pulmonary roots. Inter-commissural distances and the heights of the sinuses were measured. For geometrical reconstruction the three commissures and their vertical projections at the root base were used as reference points. RESULTS: In the pulmonary root, the three inter-commissural distances were of similar dimensions (17.9+/-1.6mm, 17.5+/-1.4mm and 18.6+/-1.5mm). In the aortic root, the right inter-commissural distance was greatest (18.8+/-1.9mm), followed by the non-coronary (17.4+/-2.0mm) and left coronary sinus commissures (15.2+/-1.9mm). The mean height of the left pulmonary sinus was greatest (20+/-1.7mm) followed by the anterior (17.5+/-1.4mm) and right pulmonary sinus (18+/-1.66mm). In the aortic root, the height of the right coronary sinus was the greatest (19.4+/-1.9mm) followed by the heights of the non-coronary (17.7+/-1.8mm) and left coronary sinus (17.4+/-1.4mm). Measured differences between parameters determine the tilt angle and direction of the root vector. The tilt angle in the pulmonary root averaged 16.26 degrees , respectively; for the aortic roots, it was 5.47 degrees . CONCLUSIONS: Herein we suggest that the left pulmonary sinus is best implanted in the position of the right coronary sinus, the anterior pulmonary in the position of the non-coronary sinus and the right pulmonary sinus in the position of the left coronary sinus. In this way, the direction of the pulmonary root vector will be parallel to that of the aortic root vector.

Adult↗
PubMed2006

Blood supply of the sternum and its importance in internal thoracic artery harvesting.

BACKGROUND: The internal thoracic artery (ITA) is the conduit of choice in coronary bypass grafting, due to the excellent long-term results achieved using it. However, increased incidence of sternal infections after pedicled ITA harvesting has revived interest in the morphology of sternal blood supply. Our aim was to discuss the topography of the sternal branches with emphasis on internal thoracic artery harvesting. METHODS: This study was conducted on 50 fresh specimens of the anterior thorax wall. Radio-opaque material was injected and angiograms of the ITA were performed. Subsequently, the specimens were preserved and a dry dissection of each ITA and its branches was carried out. RESULTS: In dry dissected specimens, four types of vessels were identified that have the potential to carry blood to the sternum after harvesting the ITA. In the first group, the artery to the sternum also supplies the intercostal space. In the second morphologic variant, the sternal branch gives off the perforating and anterior intercostal arteries. In the third group, we classified the common branch of the sternal and perforating arteries. In the fourth group, the sternal artery originated from the ITA as an independent branch. CONCLUSIONS: For sternal-intercostal, perforating-intercostal, and sternal-perforating branches to function as collaterals after ITA harvesting, the common trunk of origin must remain intact. Based on morphologic data, we recommend ligating the common trunk as close as possible to the ITA; in this way, collateral blood flow to the sternum remains intact.

Adolescent↗
PubMed2006

Clinical anatomy of the atrioventricular node artery.

BACKGROUND AND AIM OF THE STUDY: The study aim was to describe the topographical relationship of the atrioventricular (AV) node artery and mitral valve annulus fibrosus with regard to AV node dysfunction following mitral valve replacement or ring annuloplasty. METHODS: The anatomy of the AV node artery was analyzed in 55 human hearts without previous pathological alterations. Selective coronary angiograms were performed to identify the AV node origin. Run-off of the AV node artery and its topographical relationship to the mitral valve attachment was analyzed in dry-dissected hearts. The position of the AV node was verified by histological sectioning. RESULTS: The AV node artery originated from the right coronary artery in 73% of examined cases, and from the left coronary artery in 27% of cases. The left AV node artery was closely related to the mitral valve attachment, especially at the area of the left proximal part of the posterior leaflet. CONCLUSION: These morphological data were compared to clinical reports emphasizing the postoperative incidence of AV block after mitral valve implantation and ring annuloplasty. The occurrence of early postoperative AV node block ranged from 20% to 37%. By comparing the present data with available literature, it can be stated that there is a high risk of intraoperative damage to the left AV node artery during manipulation of the mitral valve annulus fibrosus.

Adult↗
PubMed2005

Aortic dissection with potential origin from a mechanical bypass anastomosis.

Ascending aortic dissection is a known complication of cardiac surgery. Off-pump coronary artery bypass surgery seems to be associated with a higher risk for this event as compared with on-pump bypass surgery. This increased risk may result from aortic side-clamping under pulsatile flow as opposed to continuous flow in conventional bypass surgery. Mechanical devices allowing performance of proximal bypass anastomoses without aortic side-clamping are supposed to reduce the risk for aortic dissection. We report a case in which ascending aortic dissection occurred 8 days after off-pump bypass surgery, most likely arising from a mechanically performed proximal bypass anastomosis.

Aged↗
PubMed2005

In the footsteps of senning: lessons learned from atrial repair of transposition of the great arteries.

The Senning operation has evolved from being the initial surgical correction that allowed survival in complete transposition of the great arteries to an integral part of the anatomic repair of congenitally corrected transposition. In patients with complete transposition, the Senning operation has given satisfactory initial and long-term surgical results, but the potential for right ventricular failure and atrial arrhythmias have drastically reduced its indications in the current era. The long-term follow-up and pertinent postoperative issues of the Senning operation will be reviewed, along with its newfound role in the anatomic repair of congenitally corrected transposition.

Arrhythmias, Cardiac↗
PubMed2005

Respiratory dependent compression of a venous bypass: therapy by stenting.

Although coronary artery bypass surgery has provided major advances in the treatment of coronary artery disease, narrowing of bypass vessels still constitutes a drawback of this therapy. Although this event is most frequently caused by intraluminal processes, obstruction from external structures is extremely rare. We report such a case in which external bypass compression was provoked by deep inspiration causing typical anginal symptoms. Percutaneous coronary intervention including stent placement provided bypass patency independent from the patient's respiratory phase. Disappearance of symptoms and absence of myocardial ischemia in perfusion scans confirmed successful treatment.

Angioplasty, Balloon, Coronary↗
PubMed2005

Normalization of high pulmonary vascular resistance with LVAD support in heart transplantation candidates.

OBJECTIVE: Pulmonary hypertension (PH) and elevated pulmonary vascular resistance (PVR) lead to poor outcome after heart transplantation due to postoperative failure of the non-conditioned right ventricle. The role of continuous flow left ventricular assist device (LVAD) support in the reduction of elevated PVR was evaluated in a series of clinical implants. METHODS: Among 17 patients with terminal heart failure receiving a MicroMed DeBakey LVAD as bridge to transplant, there were six patients with pulmonary hypertension (mean systolic PAP 47 mmHg) and high PVR (398 dynes/cm5), previously not considered suitable for heart transplantation, who underwent serial right heart catheters during their LVAD support period. RESULTS: In these patients mean systolic pulmonary pressure dropped to 29 mmHg and PVR decreased to a mean 167 dynes/cm5 under LVAD support. Clinical improvement was significant in all patients. Four patients were successfully transplanted without major postoperative difficulties (mean duration 130 days support) and all are doing well to date. Post-transplant-PVR remained in the normal range in all transplanted patients. CONCLUSIONS: Elevated PVR and severe PH were both previously considered as contraindication for heart transplantation. A period of LVAD pumping leads to a progressive decrease of PVR and normalization of pulmonary pressures, making these patients amenable for heart transplantation. LVAD as bridge to heart transplantation is safe and highly beneficial for terminal heart failure patients with severe PH.

Adult↗
PubMed2005

A new classification of the mitral papillary muscle.

BACKGROUND: Mitral valve homograft implantation and reconstruction of the left ventricular subvalvular apparatus requires a good knowledge of the morphology of the left papillary muscles. A comprehensive description of the left ventricular subvalvular apparatus is presented to aid in this procedure and to support conventional and endoscope-assisted reconstruction of the chordae tendineae. MATERIAL/METHODS: The subvalvular apparatuses of 100 unfixed human hearts were investigated. Papillary muscles were endoscopically examined on the hearts in situ, then the hearts were explanted and the subvalvular apparatus was macroscopically inspected. The geometrical arrangement of the chordae tendineae was determined. RESULTS: We defined three groups of the left ventricular papillary muscle. In group I the basal part and the apex of the muscle were undivided. In group II there were two heads; in subgroup II/A the base of the papillary muscle was undivided and in II/B it was divided into two separate parts. In group III the papillary muscle had three heads. In subgroup III/A the base was undivided, while in III/B it was made up of two and in III/C three separate parts. CONCLUSIONS: We propose a classification of the left ventricular subvalvular apparatus based on the macroscopic and endoscopic investigations. It emphasizes the morphology of the apical and basal parts of papillary muscles and includes the geometrical arrangement of the chordae tendineae. Thus it may be of a great value in endoscopic and conventional mitral valve replacement or reconstruction of the chordae tendineae and in mitral valve homograft implantation.

Adult↗
PubMed2004

Anatomic reconstruction of recurrent aortic arch obstruction in children.

OBJECTIVE: Anatomical reconstruction of the aortic arch following aortic arch surgery is challenging. The placement of an extra-anatomical aortic bypass has been proposed for these difficult cases. This approach is not ideal in children due to possible long-term complications. This study presents the results of our policy to reconstruct the aortic arch in recurrent obstruction in children, which are not amenable to balloon dilatation. METHODS: Seven children with a median age of 8 years (range 1 month-15 years) were operated for aortic arch obstruction following correction of an aortic coarctation. Six children presented another intra-cardial lesion (2 subaortic membranes; 2 VSDs, 1 ostium stenosis of the left main coronary artery, and 1 mitral valve insufficiency). The surgical approach involved a sternotomy, cardiopulmonary support using two arterial inflow cannulas (one above and one below the aortic arch), and moderate hypothermia. Enlargement of the aortic arch was performed by a sliding plasty in four patients and by a patch plasty in three patients. Associated cardiac defects were corrected as well. RESULTS: It was technically possible to perform the planned operation in all patients. All patients survived and none presented significant postoperative complications. There were no residual gradients in six patients and a gradient of 10 mmHg in one patient postoperatively. One patient showed transient recurrent nerve palsy which recovered within 6 weeks. Follow-up echocardiographic and MRI studies revealed a normal appearing aortic arch with laminar flow. CONCLUSIONS: Although more demanding, an anatomical reconstruction of the aortic arch can be performed in infants and children with recurrent obstruction of the aortic arch with excellent initial results. This approach may prove superior to an extra-anatomic bypass in the long-term.

Adolescent↗
PubMed2004

Advantages of subclavian artery perfusion for repair of acute type A dissection.

OBJECTIVE: Arterial perfusion through the right subclavian artery is proposed to avoid intraoperative malperfusion during repair of acute type A dissection. This study evaluated the clinical and neurological outcome of patients undergoing surgery of acute aortic type A dissection following subclavian arterial cannulation compared to femoral artery approach. METHODS: From 1/97 to 1/03, 122 consecutive patients underwent surgery for acute type A aortic dissection. Subclavian cannulation was performed in 62 versus femoral cannulation in 60 patients. Clinical characteristics in both groups were similar. Mean age was 61 years (SD+/-14 years, 72% male) and mean follow-up was 3 years (+/-2 years). Patient outcome was assessed as the prevalence of clinical complications, especially neurological deficits, mortality at 30 days, perioperative morbidity and time of body temperature cooling and analyzed by nominal logistic regression analysis for odds ratio calculation. RESULTS: Arterial subclavian cannulation was successfully performed without any occurrence of malperfusion in all cases. Patients undergoing subclavian cannulation showed an odds ratio of 1.98 (95% CI 1.15-3.51; P=0.0057) for an improved neurological outcome compared to patients undergoing femoral cannulation. Re-exploration rate for postoperative bleeding was significantly reduced in the subclavian group (P<0.0001), as well as occurrence of myocardial infarction (P<0.0001) and duration for body temperature cooling (P=0.004). The 30-day mortality of patients with femoral cannulation was significantly higher compared to patients with subclavian artery cannulation (24 versus 8%; P=0.0179). CONCLUSIONS: Arterial perfusion through the right subclavian artery provides an excellent approach for repair of acute type A dissection with optimized arterial perfusion body perfusion and allows for antegrade cerebral perfusion during circulatory arrest. The technique is safe and results in a significantly improved clinical and especially neurological outcome.

Adult↗
PubMed2004

Direct closure of the septum primum in atrioventricular canal defects.

OBJECTIVE: The objective of this study was to assess the safety of directly closing the septum primum during the correction of atrioventricular canal defects. METHODS: We performed a retrospective analysis of our experience with direct closure of the septum primum during the repair of atrioventricular canal defect. The series consisted of 28 consecutive patients presenting with a partial (15 patients) and complete (13 patients) atrioventricular canal defect. The cleft in the atrioventricular valve was closed completely in 25 patients and partially in 3 patients (those with a small left lateral leaflet). In complete atrioventricular canal, the ventricular septum defect was closed with a patch of polytetrafluoroethylene (Gore-Tex, W. L. Gore & Associates, Inc, Flagstaff, Ariz) or xenopericardium. Follow-up was complete and ranged from 3 to 21 months (median 11 months). RESULTS: There were no early or late deaths and no surgical complications. The septum primum defect was closed completely in all patients as assessed by echocardiography. All the patients were in sinus rhythmus, and none had even a temporary complete atrioventricular block. The surgical result and heart rhythm have remained stable over time. CONCLUSIONS: Direct closure of the septum primum is an easy, quick, and safe procedure during repair of atrioventricular defects.

Age Factors↗
PubMed2004

Early bypass occlusion after deployment of nitinol connector devices.

BACKGROUND: Reducing the negative side effects associated with extracorporeal circulation is the major advantage of off-pump revascularization. However, side clamping of a calcified aorta for proximal anastomoses can cause emboli, resulting in neurologic damage. This problem has been addressed by introducing a mechanical anastomosis device (Symmetry, St Jude Medical) that allows vein-to-aorta anastomosis without manipulating the aorta. This report describes our experience with this device. METHODS: Between June 2001 and April 2002, 77 connectors (1.3 per patient) were deployed in 61 patients (51 men and 10 women; mean age, 68 +/- 8.6 years) undergoing off-pump coronary artery bypass grafting or beating-heart revascularization. Intraoperative quality assessment included transit-time flow measurement (Medistim) and indocyanine green-based angiography (Spy, Novadaq). RESULTS: The surgeons were meticulously trained in loading of the device. No postoperative neurologic deficits were detected. Fifty-three patients had an uneventful course. However, 8 (13.1%) patients with 12 implanted connectors were symptomatic within 8 months (1 day to 8 months). Angiography revealed significant (95%) stenosis or even occlusion of the proximal vein-to-aorta anastomosis at the level of all connectors. Four patients underwent reoperation (2 dilated-stented and 2 treated with drugs). CONCLUSION: On the basis of these observations, the routine use of the connector was halted at our institution. At the moment, the use of this therapy is reserved for patients with severely calcified aortas with no technical alternative. Further investigations appear necessary to evaluate the clinical patterns of this otherwise promising technology.

Aged↗
PubMed2004

Overlapping annuloplasty of the mitral valve in children.

Harmonious reduction of the posterior annulus of the mitral valve can be a useful adjunct to obtain complete valve competence in case of annular dilatation. We present a technique with the use of two resorbable sutures that overlap over the middle third of the posterior annulus that was used in 10 children with good short-term results. Resorption of the sutures should permit subsequent normal growth of the mitral valve. If the primary cause of valvular regurgitation was corrected, it can be expected that the repair will remain stable after resorption of the sutures.

Cardiac Surgical Procedures↗
PubMed2004

Inferior partial sternotomy for surgical closure of isolated ventricular septal defects in children.

BACKGROUND: Surgical closure of isolated ventricular septal defect (VSD) through partial inferior sternotomy offers the advantages of a much shorter, cosmetically superior skin incision, potentially improved sternal stability, a lower rate of infection, and less postoperative pain. We report our technique and results of use of inferior partial sternotomy for closure of isolated VSD in children. PATIENTS AND METHODS: From July 2002 to July 2003, 24 consecutive patients with a median age of 4.5 months (range, 1 month-4.5 years) underwent partial inferior sternotomy for isolated VSD closure. The length of the incision ranged from 4 to 6 cm. Special features of the approach included T incision of the lower sternum (from the fourth intercostal space to the xiphoid), establishment of cardiopulmonary bypass with central cannulation, aortic cross-clamping, and cardioplegic arrest. All VSDs were approached through right atriotomy. Perimembranous VSDs were exposed after detachment of the anterior leaflet of the tricuspid valve and were closed with a continuous suture. Muscular VSDs were approached directly. Perioperative and postoperative echocardiographic findings were available for all patients. Follow-up was complete. RESULTS: There was no mortality or significant surgical morbidity. Median cross-clamping and cardiopulmonary bypass times were 43 and 103 minutes, respectively. All patients were in sinus rhythm. Perioperative and postoperative echocardiography confirmed the absence of any residual defects in perimembranous VSDs and the presence of a trace residual VSD in 4 patients with muscular VSDs. Optimal healing of the partial sternotomy was obtained in all patients. CONCLUSIONS: Inferior partial sternotomy is less invasive than and cosmetically superior to full sternotomy. It provides excellent results when applied to isolated VSD with standard surgical techniques.

Child, Preschool↗
PubMed2004

Review article: Tissue engineering of semilunar heart valves: current status and future developments.

Heart valve replacement represents the most common surgical therapy for end-stage valvular heart diseases. One major drawback that all heart valve replacements have in common is the lack of growth, repair, and remodeling capability once implanted into the body. The emerging field of tissue engineering is focusing on the in-vitro generation of functional, living semilunar heart valve replacements. This review presents a state-of-the-art overview of the physiological and biomechanical requirements of semilunar heart valves, focusing on the aortic valve. Moreover, recent heart valve tissue engineering is summarized and future options and improvements on the way towards clinical applications are discussed.

Animals↗
PubMed2003

Graft occlusion after deployment of the Symmetry Bypass System.

Recently the Symmetry Bypass System (SJM, St. Paul, MN) became available. Now the system is frequently applied for vein-graft to aorta anastomoses in off-pump coronary artery bypass operations. This report describes a complication associated with the use of the Symmetry Bypass System (SJM) in a patient undergoing a standard off-pump coronary artery bypass procedure. A novel imaging system (SPY, Novadaq, Toronto, Canada) was applied for intraoperative assessment of graft function, and this system immediately diagnosed the occlusion of the proximal mechanical anastomosis caused by a mobile atheromatous aortic plaque.

Aged↗
PubMed2003

Detachment of the anterior leaflet of the tricuspid valve to expose perimembranous ventricular septal defects.

BACKGROUND: Detachment of the septal leaflet of the tricuspid valve has been described for better access to perimembranous ventricular septal defects. Detachment confined to the anterior leaflet is less known, although it provides a better exposure of the subaortic area and puts less jeopardy on the conduction tissues. METHODS: Data regarding 49 consecutive patients who had congenital perimembranous ventricular septal defect closure were retrospectively reviewed. Thirty-three patients (67%) underwent temporary detachment of the anterior leaflet of the tricuspid valve. The defect was closed with a Gore-Tex patch and a continuous suture. In 10 patients (29%), concomitant right ventricular outflow tract enlargement was performed. Follow-up was obtained in every patient (median time, 11 months; range, 2 to 26 months). RESULTS: No early or late death occurred. Closure of the ventricular septal defect was complete, with no more than trivial residual jet leaks found in perioperative echocardiography. All patients were in sinus rhythm. The tricuspid valve never showed more than mild insufficiency after repair. No patient showed subaortic obstruction. CONCLUSIONS: Detachment of the anterior leaflet of the tricuspid valve to expose the ventricular septal defect is a safe approach that allows rapid closure of the defect with a continuous suture and provides excellent results.

Blood Vessel Prosthesis Implantation↗