From Zagreb, Croatia to Cleveland, Ohio. Interviewed by Barry Shurlock.
Explore the source record for details and available documents.
Croatia↗
Biomedical subjects
Tomislav Mihaljevic
Publications and source records attributed to Tomislav Mihaljevic.
Transfusion in coronary artery bypass grafting is associated with reduced long-term survival.
BACKGROUND: Perioperative red blood cell (PRBC) transfusion has been associated with early risk for morbid outcomes, but risk related to long-term survival has not been thoroughly explored. Therefore, we examined the influence of PRBC transfusion and component therapy on long-term survival after isolated coronary artery bypass grafting after controlling for the effect of demographics, comorbidities, operative factors, and the early hazard for death. METHODS: The US Social Security Death Index was used to ascertain survival status for 10,289 patients who underwent isolated coronary artery bypass grafting from January 1, 1995 through June 28, 2002. The outcome measure was all-cause mortality during the follow-up period. Unadjusted survival estimates were performed using the Kaplan-Meier techniques. Survival curves for transfusion status were compared with the log-rank test. The parametric decomposition model was used for risk-adjusted survival. A balancing score was calculated for each patient and forced into the final model. RESULTS: Survival among transfused patients was significantly reduced as compared with nontransfused patients. The instantaneous risk of death displayed a biphasic pattern: a declining hazard phase from the time of the operation (early hazard) up until 6 months postoperatively and then a late hazard that continued out until about 10 years. Transfusion of red cells was associated with a risk-adjusted reduction in survival for both the early (0.34 +/- 0.02, p < 0.0001) and late phases (0.074 +/- 0.016, p < 0.0001). CONCLUSIONS: Perioperative PRBC transfusion is associated with adverse long-term sequela in isolated CABG. Attention should be directed toward blood conservation methods and a more judicious use of PRBC.
Age Factors↗
Surgery for permanent atrial fibrillation: impact of patient factors and lesion set.
BACKGROUND: Whether a complete Cox-maze procedure is needed to ablate permanent atrial fibrillation in patients undergoing concomitant cardiac surgery is unknown. Our objective was to assess the effectiveness of different lesion sets in such patients. METHODS: From November 1991 to January 2004, 575 patients underwent surgical treatment of permanent atrial fibrillation (duration > 6 months); mitral valve disease was the primary indication for surgery in 74%. Procedures included pulmonary vein isolation alone (n = 68, 12%), pulmonary vein isolation with left atrial connecting lesions (n = 265, 46%), and Cox-maze (n = 242, 42%). Rhythm documented on 5,120 postoperative electrocardiograms was used to estimate time-related prevalence of, and risk factors for, atrial fibrillation. RESULTS: Prevalence of postoperative atrial fibrillation peaked at 46% two weeks after operation, declining to 24% at one year. Patient-related risk factors for increased prevalence included older age (p < 0.0001), larger left atrium (p < 0.0001), and longer duration of preoperative atrial fibrillation (p = 0.0008). The Cox-maze procedure and lesion sets resembling it created with alternative energy sources had a similarly low prevalence of late postoperative atrial fibrillation; in contrast, pulmonary vein isolation and lesion sets that did not include a lesion to the mitral anulus were less effective. CONCLUSIONS: This study suggests that in cardiac surgical patients with permanent atrial fibrillation the left atrial lesion set should include wide pulmonary vein isolation, at least one connection between right and left pulmonary veins, and a connection to the mitral anulus. Availability of alternative energy sources to create lesions sets has virtually eliminated the need for the cut-and-sew Cox-maze procedure.
Adult↗
Transapical aortic valve implantation: an animal feasibility study.
BACKGROUND: Percutaneous aortic valve implantation has recently been performed in nonsurgical patients with severe aortic stenosis. Retrograde valve delivery has been problematic because of the size of the delivery system and concomitant peripheral vascular disease. We investigated a minimally invasive approach through the left ventricular apex for antegrade placement of a device-deliverable valve. METHODS: Transapical aortic valve implantation was performed using a 23-mm equine valve mounted on a stainless steel stent in 24 swine (weight range, 35 to 45 kg). A limited or full sternotomy approach was used to access the apex of the heart. The crimped valve was introduced through a sheath in the left ventricular apex. Fluoroscopy and echocardiography were used for guidance. Deployments were performed on the beating heart either with ventricular unloading using femoral extracorporeal circulation or rapid ventricular pacing. RESULTS: All valves were successfully delivered at the selected target site with acceptable visualization of the noncalcified aortic annulus. Valve migration occurred during eight deployments (two distal and six retrograde) secondary to persistent cardiac output, unfavorable annular anatomy, and dislodgement by the delivery catheter. Exact positioning of the nonmigrated valves at the aortic annulus was examined by necropsy of all animals at the end of the procedures. Paravalvular leak was noted in 14 of 18 (77.8%) valves remaining in situ. CONCLUSIONS: The transapical approach was used for the successful antegrade placement of a stented valve, obviating the technical problems associated with a large delivery system transiting the peripheral vascular system. Stent design contributing to paravalvular leak remains problematic.
Animals↗
Folding valvuloplasty without leaflet resection: simplified method for mitral valve repair.
Standard repair techniques can prove challenging in patients with severe myxomatous mitral valve disease when there is a broad-based mid-portion of the posterior leaflet and small medial and lateral scallops. We describe a new surgical technique in which the mitral valve repair was accomplished by simple folding the prolapsed segment of the posterior leaflet and by insertion of the flexible annuloplasty ring.
Adult↗
Extrapleural pneumonectomy for scimitar syndrome.
Explore the source record for details and available documents.
Adult↗
Morbidity and mortality risk associated with red blood cell and blood-component transfusion in isolated coronary artery bypass grafting.
OBJECTIVE: Our objective was to quantify incremental risk associated with transfusion of packed red blood cells and other blood components on morbidity after coronary artery bypass grafting. DESIGN: The study design was an observational cohort study. SETTING: This investigation took place at a large tertiary care referral center. PATIENTS: A total of 11,963 patients who underwent isolated coronary artery bypass from January 1, 1995, through July 1, 2002. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 11,963 patients who underwent isolated coronary artery bypass grafting, 5,814 (48.6%) were transfused. Risk-adjusted probability of developing in-hospital mortality and morbidity as a function of red blood cell and blood-component transfusion was modeled using logistic regression. Transfusion of red blood cells was associated with a risk-adjusted increased risk for every postoperative morbid event: mortality (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.67-1.87; p<.0001), renal failure (OR, 2.06; 95% CI, 1.87-2.27; p<.0001), prolonged ventilatory support (OR, 1.79; 95% CI, 1.72-1.86; p<.0001), serious infection (OR, 1.76; 95% CI, 1.68-1.84; p<.0001), cardiac complications (OR, 1.55; 95% CI, 1.47-1.63; p<.0001), and neurologic events (OR, 1.37; 95% CI, 1.30-1.44; p<.0001). CONCLUSIONS: Perioperative red blood cell transfusion is the single factor most reliably associated with increased risk of postoperative morbid events after isolated coronary artery bypass grafting. Each unit of red cells transfused is associated with incrementally increased risk for adverse outcome.
Aged↗
Early and late results of isolated and combined heart valve surgery in patients > or =80 years of age.
We present a series of 405 consecutive patients aged > or =80 years who underwent isolated or combined valve surgery over a 5-year period. Our results demonstrate that valve surgery in the elderly can be performed with acceptable early mortality, good late survival, and excellent late functional outcome.
Aged↗
Postinfarction ventricular septal defect with pseudoaneurysm repair after failed percutaneous closure.
Ventricular septal defect with intramyocardial dissection of the ventricular free wall is a rare complication of myocardial infarction associated with poor prognosis. We describe a patient who developed a ventricular septal defect with intramyocardial dissection of the right ventricular free wall. Initially the patient was successfully stabilized by the placement of a percutaneous closure device. The placement of the device allowed initial hemodynamic recovery of the patient and subsequent definitive surgical repair. This case illustrates the importance of collaboration between interventional cardiologists and cardiac surgeons in the treatment of complex postinfarction ventricular septal defects.
Aneurysm, False↗
Transesophageal echocardiography for pulmonary embolectomy.
Explore the source record for details and available documents.
Echocardiography, Transesophageal↗
Intraoperative sentinel lymph node mapping of the lung using near-infrared fluorescent quantum dots.
BACKGROUND: The presence of lymph node metastases is an important prognostic marker with regard to non-small-cell lung cancer (NSCLC). Assessment of the sentinel lymph node (SLN) for the presence of tumor may improve staging. Our objective was to develop an optical noninvasive imaging tool that would permit intraoperative SLN mapping and provide real-time visual feedback for image-guided localization and resection. METHODS: Invisible near-infrared (NIR) light penetrates relatively deeply into tissue and background autofluorescence is low. We have developed a NIR fluorescence imaging system that simultaneously displays color video and NIR images of the surgical field. We recently engineered 15 nm nonradioactive NIR fluorescent quantum dots (QDs) as optimal lymphotrophic optical probes. The introduction of these QDs into lung tissue allows real-time visualization of draining lymphatic channels and nodes. RESULTS: In 12 Yorkshire pigs (mean weight 35 kg) we demonstrated that 200 pmol of NIR QDs injected into lobar parenchyma accurately maps lymphatic drainage and the SLN. All SLNs were strongly fluorescent and easily visualized within 5 minutes of injection. In 14 separate injections QDs localized to a mediastinal node, whereas in 2 injections QDs localized to a hilar intraparenchymal node. Histologic analysis in all cases confirmed the presence of nodal tissue. CONCLUSIONS: We report a highly sensitive rapid technique for SLN mapping of the lung. This technique permits precise real-time imaging and therefore overcomes many limitations of currently available techniques.
Animals↗
Impact of concomitant coronary artery bypass grafting on hospital survival after aortic root replacement.
BACKGROUND: We examined the impact of concomitant coronary artery bypass grafting (CABG) on hospital survival after aortic root replacement. We sought to determine whether CABG procedures that were not originally planned but rather added after the aortic root procedure was completed (CABG/bailout) skewed the results to shift patients with bad outcomes to the CABG group, making the non-CABG group appear undeservedly low risk. METHODS: Between May 1992 and January 2001, 369 consecutive patients underwent aortic root replacement. Concomitant CABG was required in 95 patients (26%). Indications for CABG were significant coronary artery disease in 73 patients (20%), active endocarditis or acute aortic dissection involving the coronary orifices in 14 patients (4%), and difficulty weaning from bypass because of regional wall motion abnormality from presumed but unconfirmed coronary artery disease or technical error at coronary ostial reimplantation (CABG/bailout) in 8 patients (2%). RESULTS: Operative mortality for the entire cohort was 5.7% (21 patients). The operative mortality rate for the non-CABG group was 0.4% (1 of 274 patients), and for the CABG group, 21% (20 of 95 patients; p < 0.001). Independent predictors of operative mortality in the CABG group were New York Heart Association functional class III or IV (odds ratio, 3.9; 95% confidence interval, 1.07 to 14.5), active endocarditis (odds ratio, 9.2; 95% confidence interval, 2.06 to 41.5), acute aortic dissection (odds ratio, 7.6; 95% confidence interval, 1.81 to 32.0), and failure to use retrograde cardioplegia (odds ratio, 6.4; 95% confidence interval, 1.06 to 38.8). The use of CABG/bailout was not a predictor. CONCLUSIONS: Adding CABG at the end of an aortic root procedure is a rare event, and because it is rare, there is no significant shift of risk as a result of the CABG/bailout patients on the overall CABG group.
Adult↗
Invited commentary.
Explore the source record for details and available documents.
Coronary Artery Bypass↗
Totally endoscopic robotic-assisted repair of patent ductus arteriosus and vascular ring in children.
BACKGROUND: This study reports on our initial experience with robotically assisted patent ductus arteriosus (PDA) closure and vascular ring division in children. METHODS: From April 2002 to May 2004, 15 patients underwent PDA closure (n = 9) and vascular ring repair (n = 6) by a totally endoscopic approach, utilizing the Da Vinci robotic system. The mean age of the patients was 8.3 +/- 4.7 years (range, 3 to 18) and the mean weight, 35.5 +/- 19.0 kg (range, 14.1 to 77.0 kg). Three thoracoscopic trocars were used to accommodate the endoscopic camera and two surgical instruments with an additional small incision for lung retraction. After dissection by the surgeon seated at the master console, PDA ligation with clips or division of the atretic arch and ductal ligament was performed. RESULTS: Total operative times were 170 +/- 46 minutes (PDA) and 167 +/- 48 minutes (vascular ring). One patient with vascular ring was converted to thoracotomy because of dense adhesions due to previous surgery. Precise and easy surgical maneuver was possible with the articulated surgical instruments and three-dimensional visualization in 14 patients. Intraoperative transesophageal echocardiography confirmed no persistent shunt in all PDA patients. No laryngeal nerve injury and hemorrhage were noted. All patients were extubated in the operating room. Median length of postoperative hospital stay was 1.5 days. CONCLUSIONS: Robotically assisted PDA closure and vascular ring division is a feasible and safe procedure. Future technologic improvement, including smaller instrument size and incorporation of tactile feedback, may permit application of this technique to even younger infants and intracardiac repairs.
Adolescent↗
Three dimensional computed tomographic imaging in planning the surgical approach for redo cardiac surgery after coronary revascularization.
OBJECTIVE: Reoperative cardiac surgery after previous coronary artery bypass grafting represents a surgical challenge due to the potential for injury to patent coronary grafts, aorta or right ventricle. Standard preoperative imaging using a coronary angiogram and chest radiograph (CXR) often results in inaccurate assessment of mediastinal anatomy. We aimed to evaluate 3D volume rendered computed tomographic imaging as an adjunct to standard preoperative assessment of patients requiring cardiac surgery in whom coronary artery revascularization had been performed in the past. METHODS: Between January 2003 and January 2004, 33 patients with previous coronary revascularization referred for reoperative cardiac surgery underwent preoperative 3D CT imaging in order to optimize the surgical approach. The mean age in this patient population was 72+/-8 years. The combined evaluation of CXR and conventional angiography offered incomplete insight into pertinent mediastinal topography in 85% of patients (28/33). RESULTS: The correlations for distances of the left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft from the midline and posterior sternum obtained by CT angiography (CTA) and CXR were poor, R=0.56 and 0.49, respectively. The correlation coefficients for distances between the right ventricle and the aorta to the sternum obtained by the same methods were similarly marginal, 0.58 and 0.48, respectively. The correlation coefficients for distances between the LIMA to LAD, circumflex and right coronary artery grafts from the midline obtained by CTA and conventional angiography were 0.54, -0.13 and 0.43, respectively. In seven patients (21%) the surgical strategy was modified based on the location of patent grafts in the mediastinum. The hospital mortality was 17% (5/29). Intraoperative injuries to vital structures were encountered in two patients (7%). No injuries to patent LIMA or the aorta were encountered. CONCLUSIONS: The 3D CT imaging technique is useful in defining the optimal surgical strategy for reoperative cardiac surgery. We found that CTA is superior to CXR and conventional angiography in defining the position of patent grafts and vital structures in relation to the midline and posterior sternum. Preoperative mapping of patent coronary grafts and other vital mediastinal structures reduces the morbidity of the reoperation through modification of surgical approaches.
Aged↗
Modern surgical treatment of massive pulmonary embolism: results in 47 consecutive patients after rapid diagnosis and aggressive surgical approach.
OBJECTIVES: This study retrospectively reviews an aggressive multidisciplinary approach to the treatment of massive pulmonary embolism, centering on rapid diagnosis with contrast-enhanced computed tomography of the chest to define the location and degree of clot burden and transthoracic echocardiography to document right ventricular strain followed by immediate surgical intervention when appropriate. METHODS: Between October 1999 through February 2004, 47 patients (30 men and 17 women; median age, 58 years; age range, 24-86 years) underwent emergency surgical embolectomy for massive central pulmonary embolism. The indications for surgical intervention were (1) contraindications to thrombolysis (21/47 [45%]), (2) failed medical treatment (5/47 [10%]), and (3) right ventricular dysfunction (15/47 [32%]). Preoperatively, 12 (26%) of 47 patients were in cardiogenic shock, and 6 (11%) of 47 were in cardiac arrest. RESULTS: There were 3 (6%) operative deaths, 2 with preoperative cardiac arrest; 2 of these 3 patients required a right ventricular assist device. In 38 (81%) patients a caval filter was placed intraoperatively. Median length of stay was 11 days (range, 3-75 days). Median follow-up was 27 months (range, 2-50 months); follow-up was 100% complete in surviving patients. There were 6 (12%) late deaths, 5 of which were from metastatic cancer. Actuarial survival at 1 and 3 years' follow-up was 86% and 83%, respectively. CONCLUSION: An aggressive approach to large pulmonary embolus, including rapid diagnosis and prompt surgical intervention, has improved results with surgical embolectomy. We now perform surgical pulmonary embolectomy not only in patients with large central clot burden and hemodynamic compromise but also in hemodynamically stable patients with right ventricular dysfunction documented by means of echocardiography.
Actuarial Analysis↗
Valve replacement in women of childbearing age: influences on mother, fetus and neonate.
BACKGROUND AND AIM OF THE STUDY: Currently, there is no clear consensus on the optimal type of cardiac valve prosthesis that should be placed in women of childbearing age. The risks of reoperative surgery for bioprosthetic valves must be weighed against those of anticoagulation therapy required for mechanical valves. Bioprosthetic valves placed in women of childbearing age are not necessarily superior to mechanical valves in terms of maternal or fetal outcomes. METHODS: A retrospective analysis was performed of early and late outcome in 103 women of childbearing age (mean age 28.3 +/- 5.1 years; range: 18-35 years) who underwent mechanical (n = 63) or biological (n = 40) valve replacement between January 1982 and July 2002. RESULTS: Eleven of the 40 women (28%) with biological valves had 19 pregnancies (13 vaginal births; three caesarean sections). Twelve of the 63 women (19%) with mechanical valves had 37 pregnancies (nine vaginal births, four caesarean sections). All of the women with mechanical valves became pregnant while receiving warfarin, and were subsequently placed on heparin or enoxaparin. No bleeding complications or birth defects were observed in either group. The incidence of miscarriages (32% (12/37) versus 11% (2/19), p = 0.09) and therapeutic abortions (32.4% (12/37) versus 5.3% (1/19), p = 0.06) were greater in the group with mechanical valves than with bioprosthetic valves. Freedom from reoperation at five and 10 years for biological versus mechanical valves was 79% versus 90%, and 38% versus 82%, respectively (p < 0.01), with no reoperative mortality. CONCLUSION: Biological valves are recommended in women of childbearing age, despite the fact that no birth defects were seen in children born to women with mechanical valves on warfarin, because the teratogenic effects of warfarin may be masked by the high rate of miscarriages and therapeutic abortions in this group.
Adolescent↗
In vivo optical imaging of pleural space drainage to lymph nodes of prognostic significance.
BACKGROUND: Understanding the spatial and temporal drainage patterns of the pleural space could have profound impact on the treatment of lung cancer and mesothelioma. The purpose of this study was to identify the in vivo pattern of drainage from the pleural space to prognostic lymph node stations. METHODS: Fifty-six rats underwent pleural space injection of a novel lymph tracer composed of recombinant human serum albumin (HSA) covalently conjugated to the near-infrared (NIR) fluorophore IRDye78 via an amide bond (HSA-78). Nodal uptake was imaged at 10, 20, 30, and 60 minutes and 4, 12, and 24 hours after injection with a custom system that simultaneously acquires color video, NIR fluorescence of HSA-78, and a merged picture of the two. Six pigs underwent the same procedure with imaging at 30 minutes, 1 hour, and 24 hours. RESULTS: In both the rat model and the pig model, HSA-78 drained from the pleural space to superior mediastinal lymph nodes first, followed by other intrathoracic and then extrathoracic lymph nodes over the course of 24 hours. CONCLUSION: NIR fluorescence imaging in two species shows that the superior mediastinal lymph nodes are the first to drain the pleural space. Over the course of 24 hours, the pleural space also communicates with other intrathoracic and then extrathoracic lymph nodes. This study also demonstrates an intraoperative method for identifying nodes communicating with the pleural space, with potential utility in the staging and/or resection of lung cancer and mesothelioma.
Animals↗