Congenital heart surgery: expected versus observed surgical performance according to the Aristotle complexity score.

BACKGROUND: The Aristotle score quantifies the complexity involved in congenital heart surgery. It defines surgical performance as complexity score times hospital survival. We studied how expected and observed surgical performance evolved over time. METHODS: 2312 main procedures carried out between 2006 and 2010 were analyzed. The Aristotle basic score, corresponding hospital survival and related observed surgical performance were estimated. Expected survival was based on the mortality risks published by O'Brien and coauthors. Observed performance divided by expected performance was called the standardized ratio of performance. This should trend towards a figure above 100%. Survival rates and performance are given with 95% confidence intervals. RESULTS: The mean Aristotle basic score was 7.88 ± 2.68. 51 patients died: observed hospital survival was 97.8 % (97.1 %-98.3%). 115 deaths were anticipated: expected survival was 95.2% (93.5%-96.3%). Observed and expected surgical performance reached 7.71 (7.65-7.75) and 7.49 (7.37-7.59), respectively. Therefore the overall standardized ratio of performance was 102.94%. The ratio increased from 2006 (ratio = 101.60%) to 2009 (103.92%) and was 103.42% in 2010. Performance was high for the repair of congenital corrected transposition of the great arteries and ventricular septal defect (VSD) by atrial switch and Rastelli procedure, the Norwood procedure, repair of truncus arteriosus, aortic arch repair and VSD closure, and the Ross-Konno procedure, with corresponding standardized ratios of 123.30%, 116.83%, 112.99%, 110.86% and 110.38%, respectively. With a ratio of 82.87%, performance was low for repair of Ebstein's anomaly. CONCLUSION: The standardized ratio of surgical performance integrates three factors into a single value: procedure complexity, postoperative observed survival, and comparison with expected survival. It constitutes an excellent instrument for quality monitoring of congenital heart surgery programs over time. It allows an accurate comparison of surgical performance across institutions with different case mixes.

Surgical management of congenital heart disease: correlation between hospital costs and the Aristotle complexity score.

BACKGROUND: Hospital costs are expected to correlate with clinical complexity. Do costs for congenital heart surgery correlate with Aristotle complexity scores? METHODS: 442 inpatient stays in 2008 were evaluated. Aristotle scores and levels were determined. Costs were estimated according to the German Institute for Hospital Reimbursement system. Pearson and Spearman R correlation coefficients and corresponding goodness-of-fit regression coefficients R2 were calculated. RESULTS: Mean basic and comprehensive Aristotle scores were 7.60 +/- 2.74 and 9.23 +/- 2.94 points, respectively. Mean expenses per hospital stay amounted to 29,369 +/- 30,823 Euros. Aristotle basic and comprehensive scores and levels were positively correlated with hospital costs. With a Spearman R of 1 and related R2 of 0.9436, scores of the 6 Aristotle comprehensive levels correlated best. Mean hospital reimbursement was 26,412 +/- 17,962 Euros. Compensation was higher than expenses for patients in comprehensive levels 1 to 3, but much lower for those in levels 4 to 6. CONCLUSIONS: Aristotle comprehensive complexity scores were highly correlated with hospital costs. The Aristotle score could be used as a scale to establish the correct reimbursement after congenital heart surgery.

Congenital heart surgery: applicability of hospital reimbursement according to German diagnosis-related groups system in conformity with the Aristotle complexity score.

BACKGROUND: Scores of Aristotle comprehensive complexity (ACC) levels have been demonstrated to correlate with the case-mix index (CMI) (cost-weights) generated by the German Diagnosis-Related Groups (DRG) 2009 version (G-DRG 2009). The equation used was "y = 0.5591 + 0.939 x" whereby y stands for cost-weight and x for ACC score. We hypothesised that each ACC level could be assigned a DRG (ACC DRG) and be used to determine hospital reimbursement. METHODS: 185 patients underwent cardiac surgery between January and June 2009. The ACC scores of these 185 patients were grouped in ACC levels, based on the basic cost-weight value of their DRG. One ACC DRG was assigned to each group and a corresponding cost-weight calculated based on the aforementioned equation. The resulting ACC CMI was compared with the CMI generated by the G-DRG 2009 (G-DRG 2009 CMI). Finally, the ACC surgical performance (complexity x hospital survival) was used to calculate the cost-weight; the obtained CMI was called "effective ACC CMI". RESULTS: Mean ACC score was 9.515 +/- 3.611 points. Derived ACC CMI and related G-DRG 2009 CMI were 9.494 and 8.438, respectively. Hospital survival was 97.8 % (181/184). Therefore ACC surgical performance and "effective ACC CMI" were 9.306 and 9.297, respectively. For each ACC level, the number of patients (n), mean ACC score, ACC CMI and related G-DRG 2009 CMI were as follows: Level 1: n = 25, 4.024 +/- 0.879, 4.338 and 5.911; Level 2: n = 30, 6.563 +/- 0.574, 6.722 and 6.602; Level 3: n = 43, 8.665 +/- 0.540, 8.695 and 8.088; Level 4: n = 73, 11.730 +/- 1.690, 11.574 and 9.612; Level 5: n = 14, 16.710 +/- 1.380, 16.249 and 11.843, respectively. CONCLUSIONS: The Aristotle score can be used to adjust hospital reimbursement by assigning a DRG and cost-weight value to each ACC level. Missing figures for level 6 can be obtained from a previous study which showed a mean score of 22.11 +/- 1.24: the ACC CMI would be 21.320. The 6 ACC DRGs indicate the correct compensation based on the complexity of the procedure. Reimbursement using the German DRG 2009 appears to favour less complex cases, while procedures with a higher complexity are penalised. Reimbursement according to "effective ACC CMIs" would have a strong impact by supporting units providing high-quality care.

Function of Contegra valved grafts after unifocalization.

BACKGROUND: Can Contegra grafts withstand high pressure? METHODS: The function of Contegra grafts implanted after unifocalization of major aortopulmonary collateral arteries (MAPCAs) in 10 patients was evaluated. Median age at repair was 194 days and two conduit sizes were used: 12 mm (n = 8) and 14 mm (n = 2). Echocardiography and heart catheterization findings were reviewed. RESULTS: Two patients died: one early after repair, one late. Death was not graft related. The median duration of observation for survivors was 31 (range 4 - 42) months. The postoperative right ventricular/left ventricular pressure ratio was greater than 75 % in 9 patients. High pressures persisted in 6 survivors. Seven patients underwent interventional dilatation/stenting of pulmonary arteries on 19 occasions. No obstruction was detected in the conduit. Graft valve regurgitation increased in 5 patients, but never exceeded grade 2 (n = 4). Freedom from reoperation for conduit dysfunction/failure was 100 % at month 42. CONCLUSION: At mid-term follow-up, the Contegra grafts withstood high pressure without significant dysfunction or aneurysmal dilatation requiring surgery. Contegra appears to be an acceptable alternative to the aortic homograft for use after unifocalization of MAPCAs in infancy.

Cerebral blood volume changes during closure by surgery of patent ductus arteriosus.

BACKGROUND: Surgical closure of a patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants has been associated with impaired neurodevelopmental outcome. Surgical PDA closure may result in abrupt changes of cerebral haemodynamics. OBJECTIVE: To examine the cerebral blood volume changes occurring after surgical closure of PDA. DESIGN: Continuous cerebral near-infrared spectroscopy (NIRS) recording throughout PDA surgery. SETTING: Tertiary neonatal intensive care unit, with PDA surgery performed on the ward. PATIENTS: Ten VLBW infants, median birth weight 748 g (range 590-1070), gestational age 24 (23-27) weeks, chronological age 14 (12-22) days. INTERVENTION: Surgical closure of PDA. MAIN OUTCOME MEASURES: Changes in cerebral oxygenated haemoglobin, cerebral deoxygenated haemoglobin, and tissue oxygenation index (measured), changes in cerebral blood volume (CBV) and cerebral haemoglobin difference (calculated) as measured by NIRS. RESULTS: During the first 2 minutes after closure of the PDA, CBV increased significantly (mean (SD) 0.14 (0.12) ml/100 g tissue; p = 0.01) and returned to baseline within 2-5 minutes. Cerebral oxygenation did not change. CONCLUSIONS: There is a short-lasting increase in CBV immediately after surgical closure of PDA, but no change in cerebral oxygenation. These transient changes are unlikely to cause harm.

Congenital aortic regurgitation due to absent aortic cusps and high-degree mitral stenosis.

Congenital absence of aortic cusps leads to severe aortic regurgitation. We present a newborn with this rare entity with extreme mitral stenosis. Hemodynamic features were those of hypoplastic left heart syndrome. Surgical management consisted of initial modified Norwood procedure followed by orthotopic heart transplantation.

Uniform long-term gene expression using adeno-associated virus (AAV) by ex vivo recirculation in rat-cardiac isografts.

BACKGROUND: Gene therapy in cardiovascular disease promises to be of great impact. The ideal vector for the therapeutic gene transfection remains to be determined. The aim of the present study was to investigate the efficacy of gene transfer using adeno-associated virus vectors carrying the lacZ-reporter gene (AAV-lacZ) in a previously described coronary recirculation model. METHODS: Beating Lewis rat hearts perfused with oxygenated Krebs-Henseleit solution were harvested, after which an atrial septal defect (ASD) was created. All vessels were tied, and AAV-lacZ was injected into the aortic root. The solution was recirculated through the ASD to the left side of the heart and pumped back to the coronary arteries by the left ventricle. Incubation was allowed for 20 min at 15 degrees C, and the hearts were subsequently transplanted heterotopically in syngeneic rats. Three increasing doses (109, 1,010, 1,011 e. u.) of AAV-lacZ virus vectors were used to study the rate of gene transfer. All hearts were harvested after 7-60 days and evaluated histologically for expression of the lacZ-gene. RESULTS: Dose-dependent gene transfer was observed. Even after 60 days, there was no obvious decline in gene expression. CONCLUSION: Adeno-associated virus vectors offer effective and uniform gene transfer in the myocardium after transcoronary injection and recirculation. Due to the lack of immune response previously described, no decrease in gene expression can be observed up to 60 days after injection.

Fetoscopic direct fetal cardiac access in sheep : An important experimental milestone along the route to human fetal cardiac intervention.

BACKGROUND: Fetal cardiac interventions by direct ultrasound-guided approaches or open fetal cardiac surgery have been fraught with technical difficulties, as well as with significant maternal and fetal morbidity in humans. Therefore, the purpose of our study in sheep was to assess the feasibility and potential of fetoscopic direct fetal cardiac access. METHODS AND RESULTS: In 15 anesthetized pregnant ewes (88 to 109 days of gestation; term, 145 days), 3 to 4 trocars were percutaneously placed in the uterus. Using videofetoscopic equipment, we assessed the feasibility of achieving direct fetal cardiac access. Minimally invasive direct fetal cardiac access by operative fetoscopy was achieved in 10 of the 15 fetal sheep. In 7 fetuses, the approach was successfully tested for fetal cardiac pacing (n=5) or antegrade fetal cardiac catheterization (n=2). Access was not achieved in 5 fetuses because of bleeding complications (n=2) or because the fetoscopic setup could not be established (n=3). All but 2 fetal sheep were alive at the end of the procedure. Acute fetal demise resulted from maternal hypotension or kinking of the fetal inferior caval vein by sternal suspension. Six ewes continued gestation; 3 of these went to term, with a normal fetal outcome. Two ewes died from septicemia 3 and 7 days after the procedure, and 1 ewe aborted 1 month after the procedure. CONCLUSIONS: Minimally invasive direct fetal cardiac access by operative fetoscopy is feasible in fetal sheep. The fetoscopic approach carries important potential for fetal cardiac pacing, antegrade fetal valvuloplasties, and resection of fetal intrapericardial teratomas in human fetuses.

Wound complications after left ventricular assist device implantation.

BACKGROUND: Wound necrosis and infection pose a tremendous risk for patients with left ventricular assist devices. METHODS: We analyzed our database of patients with left ventricular assist devices for those who developed wound dehiscence and concomitant infection after left ventricular assist device implantation. RESULTS: Three of our 66 patients (4.5%) with implantable ventricular assist devices had had severe wound complications with necrosis of the abdominal or thoracic wall uncovering part of the device. The predominant impact on the development of these complications was presumably related to multiple surgical interventions on the same site. CONCLUSIONS: Nevertheless, these patients can recover and undergo successful heart transplantation if adequately managed.

Operative techniques and strategies for minimally invasive fetoscopic fetal cardiac interventions in sheep.

BACKGROUND: Recent efforts to develop procedures for fetoscopic fetal cardiac interventions have been prompted by the development of severe secondary damage to the fetal heart due to semilunar valvar obstructions and the poor outcome of therapy-refractory fetal arrhythmias. The purpose of our manuscript is to analyze and share our experience with the creation of an operative setup for these procedures in sheep. METHODS: We studied a total of 48 fetal sheep between 81 and 106 days of gestation (term, 145 days). After entering the amniotic cavity by a percutaneous approach, we performed various fetoscopic fetal cardiac procedures. We analyzed the success of percutaneous fetal access, methods of trocar support, the incidence and management of trocar dislodgement or accidental insertion into the chorioamniotic space, problems related to amniotic insufflation and trocar placement, as well as techniques for fetal posturing and uterine closure. RESULTS: Percutaneous fetal access was achieved in all sheep. The use of resterilizable trocars substantially decreased the costs of our procedures. Utilizing a percutaneous transuterine purse-string suture for trocar support helped to minimize the number of nonabsorbable T-fasteners remaining inside the uterus postoperatively. As complications such as trocar dislodgement, insertion of the trocar into the chorioamniotic space, and problems with intraamniotic insufflation and gas loss were mastered, conversion to an open operative approach was never required. A novel strategy that we devised for percutaneous fetal posturing permitted adequate fetal posturing with ease and minimal trauma to the fetal skin. CONCLUSION: As operative techniques have become more refined, the feasibility of performing fetoscopic fetal cardiac interventions in human fetuses now depends mainly on technical improvements in imaging and interventional catheters, as well as advances in pacemaker equipment.

Effective gene transfer in the rat myocardium via adenovirus vectors using a coronary recirculation model.

BACKGROUND: Gene therapy promises to play an important role in the treatment of heart disease and in transplantation. The limited effectiveness of gene transfer, however, remains an unresolved problem. The aim of the study was to create a model for more effective gene transfer using adenovirus vectors carrying the lacZ-reporter gene (AdV-lacZ). METHODS: Beating Lewis rat hearts perfused with oxygenated Krebs-Henseleit solution were harvested, after which an atrial septal defect (ASD) was created. All vessels were tied and AdV-lacZ was injected into the aortic root. The solution was recirculated through the ASD to the left side of the heart and pumped back to the coronary arteries by the left ventricle. Incubation was allowed for 20 min at 15 degrees C and the hearts were subsequently transplanted heterotopically in syngeneic rats. This method was compared to AdV-lacZ injection into cardioplegic hearts. The hearts were harvested after 2, 7, or 14 days and evaluated histologically for expression of the lacZ gene. RESULTS: Maximal gene expression was achieved after 7 days by the recirculation model. There was less efficient gene expression at day 2 and at day 14. No evidence of ischemic injury of the myocardium was noticed histologically. Almost no successful gene expression was seen in the arrested hearts. CONCLUSION: This novel recirculation method lets the vector be repeatedly exposed to the endothelium, resulting in an effective gene expression after 7 days incubation time rather than after 14, when a decline has set in presumably due to immunologic response.

Fetoscopic transesophageal electrocardiography and stimulation in fetal sheep: a minimally invasive approach aimed at diagnosis and termination of therapy-refractory supraventricular tachycardias in human fetuses.

BACKGROUND: Therapy-refractory supraventricular tachycardia commonly results in hydrops and death in human fetuses. The purpose of this study in fetal sheep was to assess the feasibility of a minimally invasive fetoscopic approach for fetal transesophageal electrocardiography and stimulation aimed at diagnosis and termination of these tachycardias. METHODS AND RESULTS: We studied a total of 10 fetal sheep (87 to 103 days of gestation; term=145 days). We entered the amniotic cavity using a percutaneous fetoscopic approach and placed various electrophysiology catheters into the fetal esophagus. We recorded the number of animals in which fetoscopic transesophageal electrocardiography and stimulation were successful and assessed pacing success and thresholds for different catheters. In addition, we monitored for potential adverse effects from stimulation and for other complications of the operation. Recording of transesophageal electrocardiograms was successful in all fetal sheep. Capture during stimulation was successfully documented by additional fetal bipolar surface electrocardiograms in 7 fetuses. In fetuses in which fetal surface electrocardiograms were not recorded, pacing stimulus artifacts interfered with documentation of capture. Although stimulation thresholds were high, the maternal rhythm was not affected by fetal stimulation. CONCLUSIONS: Fetoscopic fetal transesophageal electrocardiography and stimulation are feasible in fetal sheep. This minimally invasive approach might have the potential to improve diagnosis and management of therapy-refractory supraventricular tachycardias in human fetuses.

Milrinone modulates endotoxemia, systemic inflammation, and subsequent acute phase response after cardiopulmonary bypass (CPB).

BACKGROUND: Compromised splanchnic perfusion and the resulting intestinal mucosal injury leads to a decreased mucosal barrier function, which allows translocation of intestinal flora and endotoxemia. The authors evaluated the effects of milrinone on splanchnic oxygenation, systemic inflammation, and the subsequent acute-phase response in patients undergoing coronary artery bypass grafting. METHODS: This open, placebo-controlled randomized clinical study enrolled 22 adult patients in two groups. Before induction of anesthesia, baseline values were obtained and patients were randomized to receive milrinone (30 microg/kg bolus administered progressively in 10 min, followed by a continuous infusion of 0.5 microg x kg(-1) x min(-1)) or saline. The following parameters were determined: hemodynamics; systemic oxygen delivery and uptake; arterial, mixed venous and hepatic venous oxygen saturation; intramucosal pH (pHi); and mixed and hepatic venous plasma concentrations of endotoxin, interleukin 6, serum amyloid A, and C-reactive protein. RESULTS: Milrinone did not prevent gastrointestinal acidosis as measured by pHi, but its perioperative administration resulted in significantly higher pHi levels compared with control. Venous and hepatic venous endotoxin and the interleukin 6 concentration were reduced significantly in the milrinone group. Serum amyloid A values were attenuated in the milrinone group 24 h after surgery. No significant differences could be seen in routinely measured oxygen transport-derived variables. CONCLUSIONS: Perioperative administration of low-dose milrinone may have antiinflammatory properties and may improve splanchnic perfusion in otherwise healthy patients undergoing routine coronary artery bypass grafting.

Transplant vasculopathy.

Transplant vasculopathy constitutes the major impediment to long-term survival in heart transplant recipients. Within the "response to immune injury" paradigm, it can best be understood as the resultant of an orchestrated recipient immune response to the initial allogenic stimulus by graft vascular endothelium. This response incorporates the elaboration of complex coordinated cytokine patterns and corresponding cell types including B-lymphocytes, T-helper1- and T-helper2-cells, cytotoxic T-cells, macrophages, and polymorphonuclear cells. These attack the alloantigenic vascular endothelium and lead, by complex cytokine signaling, to migration of donor smooth muscle cells from the media into the intima, associated with a switch from the contractile to a synthetic phenotype. In conjunction with recipient T-cells, macrophages, and lipids, the intimal fibroproliferative growth of the donor vessel is hereby initiated.

The influence of body temperature on transient evoked otoacoustic emissions.

Thirty patients undergoing open heart surgery under induced hypothermia had transient evoked otoacoustic emissions (TEOAE) recorded during cooling to 26.07 degrees C (standard deviation (SD) 4.25 degrees C) vesically measured temperature and 24.86 degrees C (SD 4.7 degrees C) nasopharyngeally measured temperature respectively. Subsequently tè patients were rewarmed until normal body temperature was reached again. There was a clear influence of body temperature on the amplitudes and reproducibilities of the TEOAE. The relationship of temperature and amplitude or reproducibility during the cooling phase was significantly different from that during rewarming. No TEOAE were measurable during cooling at a mean temperature lower than 33.41 degrees C (SD 2.04 degrees C) vesical temperature and 30.16 degrees C (SD 3.0 degrees C) nasopharyngeal temperature respectively. During rewarming the echoes became recognizable again at a mean temperature of 28.75 degrees C (SD 3.38 degrees C) vesical temperature and 27.49 degrees C (SD 2.99 degrees C) nasopharyngeal temperature. These results suggest a hysteresis in the relationship between the amplitude of TEOAE and temperature, similar to the well-established relationship between evoked potentials and temperature.

Renal insufficiency in neonates after cardiac surgery.

Renal failure after cardiac surgery using cardiopulmonary bypass (CPB) is well understood for infants, children and adults. The perioperative risk factors after CPB for immature kidneys in newborns are not well known. This retrospective study investigates perioperative risk factors for renal insufficiency in neonates. I) Preoperative: Age; weight, performed angiography, amount of dye used in angiography, renal disease and creatinine. II) Intraoperative: Duration of operation, duration of MAP < 40 mmHg, use of deep hypothermia, in-out fluid balance, duration of CPB, duration of circulatory arrest and cross-clamp time. III) Postoperative: Creatinine, use of catecholamines, use of nitroglycerine (NG) or phosphodiesterase inhibitors (PDI) and additional antibiotics. From Jan. 1990 to Dec. 1994 50 neonates underwent cardiac surgery using CPB (n = 23 transposition of the great arteries; n = 4 pulmonary atresia; n = 6 critical pulmonary stenosis; n = 5 hypoplastic left heart syndrome; n = 3 Ebstein's anomaly; n = 2 interrupted arch with hypoplastic left ventricle; n = 2 single ventricle; n = 1 each: double outlet right ventricle, tricuspid atresia, critical aortic stenosis, rhabdo-myosarkoma, corrected transposition of the great arteries.) Thirty-one patients entered the study. Depending on the postoperative creatinine level two groups (group I: creatinine <1 mg/dl and group II: >1 mg/dl) were created. The diureses between the two groups did not differ. Comparing the patients of group I vs. group II, patients of group I were younger (mean age: 7.7 d. vs. 11.4 d), lighter (mean weight: 3260 g vs. 3430 g), less had angiography (44% vs. 77%), received more dye (mean amount: 14 ml vs. 7 ml), the duration of MAP < 40 mmHg while on CPB was longer (mean duration 3 min vs. 21 min), more patients were operated on using deep hypothermia (55% vs. 27%), the postoperative in-out-fluid balance was more positive (mean balance +413 ml vs. +221 ml), received postop. more frequently high doses of catocholamines and less common NG or PDI, but more often additional antibiotics. The duration of circulatory arrest (mean time: 60 min vs. 55 min) and cross clamp time (mean time: 68 min vs. 65 min) seems not to be a risk factor and vasodilators given simultaneously with catecholamines may have preventive effects on postoperative renal insufficiency. Immature kidneys may play an outstanding role in the susceptibility of damaging factors. Further investigation with a larger number of patients allowing to obtain statistical significant risk factors are required.

Comparative analysis of glutaraldehyde-preserved porcine xenografts and fresh or glutaraldehyde-treated human aortic valves by holographic interferometry.

Although calcification and degeneration are recognized as the main causes of bioprosthetic heart valve failure, the reasons for such failure are not well understood. Hidden tissue anomalies in the valves may be the origin of later calcification. Application of hologram interferometry for non-destructive testing enables the detection of such tissue anomalies. A comparative study by holographic interferometry of ten porcine bioprosthetic valves (seven Carpentier-Edwards SAV, two BioImplant and one Valcor) with five human aortic valves before and after glutaraldehyde treatment is presented. Whereas irregularities were detected in the interferograms of eight out of ten bioprostheses, no similar distorted fringe pattern was found in the holographic interferograms of human specimens. The present results suggest that tissue abnormalities exist in standard bioprosthetic valves which are absent in human ones. These irregularities may be the origin of later calcification and valvular dysfunction.

A simple technique for thoracoscopic resection of lung tumors.

Mainly incited by the bushfirelike spread of endoscopic operative techniques in general surgery, thoracoscopy has become the object of new interest in the field of thoracic surgery. Location and resection of lung tumors are problematic for several reasons and so far not standardized. The main problems are pointed out. A new technique together with the instruments and their advantages is demonstrated. Future aspects are discussed.

Surgical experience with defibrillator implantation using nonthoracotomy leads.

Between October 10, 1989, and June 17, 1991, 109 patients with life-threatening ventricular arrhythmias received an implantable cardioverter-defibrillator at our institution. In 50 patients, nonthoracotomy lead systems consisting of a subcutaneous chest wall patch electrode near the cardiac apex and one (Cardiac Pacemakers, Inc: Endotak C) or two (Medtronic: Transvene) transvenous electrodes were tested. The mean ejection fraction was 0.44 +/- 0.15 with a range from 0.19 to 0.81. Twenty-four patients had a history of open heart operation. In 43 patients the nonthoracotomy lead system was implanted, whereas in 7 patients epicardial patch lead systems were required due to elevated defibrillation thresholds during nonthoracotomy lead testing. There was one perioperative death unrelated to the operative procedure (hydrocephalus internus). Hemorrhage from the subcutaneous patch pocket or the device pocket that required reintervention occurred in 4 patients. During a mean follow-up of 13 +/- 5 months (range, 4 to 26 months) no dislocation of an endocardial lead, insulation defect, or lead fracture has been observed. In 1 patient, the lead system had to be removed due to infection of the subcutaneous patch pocket. The cardiovascular survival rate was 98% at 12 and 18 months, and freedom from sudden cardiac death was 100% at 6 and 12 months. In conclusion, defibrillator implantation using nonthoracotomy lead systems is feasible with a success rate of 86%, and during short-term follow-up no problems related to the lead system such as dislocation, fracture, or insulation defect have occurred.