20 years of arterial switch operation for simple TGA.

BACKGROUND: Arterial switch operation became the golden treatment for simple transposition of the great arteries (sTGA). We describe our experience with the arterial switch operation regarding long-term outcome and the need for re-intervention. Nevertheless, supravalvular pulmonary stenosis (SPS) remains a concern in the long run. We assess the evolution of SPS over time and evaluate the effect of technical modifications on SPS during our experience. METHODS: We performed a retrospective study on 133 patients operated with ASO for TGA between October 1991 and November 2009. Last report method was used. We reviewed our pediatric cardiology and cardiac surgery database to examine the echocardiographic data and electrocardiograms. A mean follow-up of 9.2 years (+/- 5.83 SD) was reached. RESULTS: One (0.8%) patient deceased postoperatively due to cardiogenic shock. The overall actuarial freedom from reoperation (open and percutaneous) was 88.1%, 78.5% and 76.9% at 1, 5 and 10 years. SPS needed to be treated in 17 patients. Valve regurgitation at final investigation was maximal moderate in 5 patients for the aortic valve, 10 for pulmonary valve and 3 in tricuspid valve. CONCLUSIONS: ASO shows excellent long-term results in sTGA with a very low morbidity and mortality and is therefore the procedure of choice. Re-intervention rate is determined by SPS. Since the extensive mobilization of the pulmonary arteries and the creation of a longer neo-pulmonary root, reduction in SPS was seen with no re-interventions in the second half of the group. To obtain a final comparison with the atrial switch operation, a longer Follow-up is necessary.

European Contegra multicentre study: 7-year results after 165 valved bovine jugular vein graft implantations.

OBJECTIVE: The valved bovine conduit "Contegra" for RVOT reconstruction became available for clinical use within a 100 % source data monitored and echo core lab controlled prospective European Multicentre Study, carried out from 1999 to 2006. We present the results of this study. METHODS: A total of 165 Contegras were implanted in 8 centres. The mean patient age was 3.9 years (2 days - 18 years, median 2.0). Total follow-up was 687 patient years. Diagnoses included: tetralogy of Fallot (64 patients, 39 %), truncus arteriosus (50, 30 %), double outlet right ventricle (16, 10 %), aortic valve disease/Ross procedure (11, 7 %), pulmonary valve atresia (10, 6 %), transposition of the great arteries (10, 6 %), 4 other malformations (2 %). Previous procedures were: 82 patients (50 %) - none; 37 (22 %) - valved conduit implantation; 14 (8 %) aortopulmonary shunt; 6 (4 %) catheter intervention. Follow-up appointments which included standardised echocardiography investigations were scheduled at 1, 3, 6, and 12 months, then annually. We evaluated freedom from death, explantation, intervention, stenosis, insufficiency, and degeneration. Results were stratified by age, diagnosis group and conduit size. RESULTS: The 5-year freedom-from rates were: explantation - 90 % (for patients aged 1 to 10 years) and 68 % (for younger patients); endocarditis - over 92 %; catheter intervention - 74 % (patients with congenital malformations); stenosis - 75 % and more (any group); insufficiency - 50 % (12 and 14 mm diameter conduits); any event - 13 % (patients under 1 year), 58 % (1 to 10 years), 82 % (> 10 years). Trace or mild insufficiency was a frequent, but not progressive finding. Mild calcification was detected in only 8 examinations. CONCLUSIONS: The performance of the Contegra conduit compares well with that of homografts when used to reconstruct paediatric right ventricular outflow tracts.

ALCAPA syndrome: an example of chronic myocardial hypoperfusion?

OBJECTIVES: The purpose of this study was to evaluate functional variables and morphologic correlates of chronically hypoperfused myocardium before and after revascularization. BACKGROUND: Neonates with congenital anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA syndrome) develop some myocardial necrosis shortly after birth. The survivors of this event are left with a localized infarction and an almost entirely collateral circulation-dependent perfusion of the left ventricle that results in poor global left ventricular function. Survival beyond infancy is uncommon because of severe left heart failure. Revascularization, however, brings about functional recovery with good clinical outcome. The ALCAPA syndrome is thus characterized by chronic collateral circulation-dependent low perfusion, low contraction matching and potential revivability. METHODS: Five patients with ALCAPA syndrome are presented, with preoperative and postoperative clinical findings and histologic data obtained from intraoperative transmural biopsy specimens. RESULTS: The angiographically assessed preoperative ejection fraction was 33 +/- 19% (mean +/- SD). Postoperative echocardiographic follow-up revealed normal left ventricular function in all patients. Histologic study of the biopsy specimens taken from the region perfused by the anomalous artery showed a variable degree of fibrosis (51 +/- 32%). The ultrastructure of the remaining myocytes revealed viable characteristics, but a substantial percent (46 +/- 26%) showed a markedly reduced fraction of contractile material. CONCLUSIONS: These ultrastructural studies suggest delayed subcellular adaptive responses in the chronically hypoperfused myocardium of patients with ALCAPA syndrome.

Rheologic genesis of discrete subvalvular aortic stenosis: a Doppler echocardiographic study.

To determine whether morphologic structures or abnormal flow patterns predispose to pathologic proliferation of subvalvular tissue, 26 patients (mean age 19.8 +/- 10.3 years) were studied greater than or equal to 6 months after operation for isolated discrete subvalvular aortic stenosis. The aortic root diameter and the mitral-aortic separation were measured with sector echocardiography. Flow patterns in the left ventricular outflow tract of these patients and control subjects were evaluated with a color flow mapping system optimized for the detection of turbulence. All control subjects had laminar flow throughout systole in the left ventricular outflow tract. By contrast, turbulence originating well below the site where the shelf had previously been resected was observed in 20 (77%) of the 26 patients. In 16 of these 20 patients turbulence was caused by a ridge, which in 13 patients could be identified as the offshoot of a ventricular band. In four patients the turbulence was caused by malalignment of the muscular and membranous septum, resulting in protrusion of the muscular septum into the outflow tract. Except for the latter four patients, the aortic root diameter was 84 +/- 10% of values predicted by body surface area, with values in six patients falling below the third percentile (p less than 0.01). The mitral-aortic separation was 9.7 +/- 3.5 mm, values in 21 patients falling above the 97th percentile (p less than 0.001). These data support the theory that discrete subvalvular aortic stenosis may be caused by a chronic flow disturbance, preferably in a small and long outflow tract. Left ventricular bands, if reaching the outflow tract, may be a factor.(ABSTRACT TRUNCATED AT 250 WORDS)

Transverse arch hypoplasia predisposes to aneurysm formation at the repair site after patch angioplasty for coarctation of the aorta.

OBJECTIVES: This study used magnetic resonance imaging (MRI) to evaluate the morphology and pathophysiology of aneurysm formation after patch angioplasty for coarctation of the aorta. BACKGROUND: Late aneurysm formation at the repair site is a well known and frequent complication after patch angioplasty. However, because the underlying mechanisms remain unresolved, postoperative outcome is unpredictable and adequate follow-up difficult. METHODS: Seventy-three of 85 patients with patch angioplasty for coarctation of the aorta were screened for aneurysm formation. Magnetic resonance imaging was performed in all 33 patients with an aneurysm, and results were compared with those for 13 control patients and 10 normal subjects. Mean (+/- SD) time between operation and MRI was 12.0 +/- 2.0 years. Aneurysm was defined as the ratio of the diameter of the aorta at the repair site to the diaphragmatic aorta > or = 1.5. Hypoplasia of the transverse arch and recoarctation at the repair site were defined as a ratio < 0.9. Transverse arch ratios on MRI were compared with those on preoperative cineangiography and the pressure gradient between the patient's right and left arm. RESULTS: All 33 patients with an aneurysm had a hypoplastic transverse arch. The 13 patients with a normal ratio at the repair site had a normal transverse arch ratio (chi square, p < 0.0001). Logarithmic regression showed a significant negative correlation (r = 0.62) between the repair site and transverse arch ratios. A significant pressure difference between the patient's right and left arm was found in patients with versus those without aneurysm (p = 0.0009). No significant difference was found between transverse arch ratios on preoperative cineangiography and postoperative MRI (mean 0.014 +/- 0.1, p = 0.4). CONCLUSIONS: Aneurysm formation at the repair site is highly related to hypoplasia of the transverse arch. Sufficient catch-up growth of a hypoplastic transverse arch is rare after late patch angioplasty. Dynamic phenomena, such as flow acceleration and turbulence, originating in a narrow transverse arch, may contribute to aneurysm formation at the repair site after patch angioplasty.

Dehiscence of a valved conduit in the ascending aorta following low-velocity blunt chest trauma: case report.

We report a case of a 56-year old man presenting with dehiscence of a valved conduit in the ascending aorta following low-velocity blunt thoracic trauma. The patient had a history of a Bentall procedure in 1994. Two weeks before referral to our hospital, the patient fell during a bicycle ride and hit the handlebars of the bicycle with his chest. During the days following the accident, the patient developed progressively worsening fatigue, shortness of breath, and intolerance for even minor physical effort. The presence of an enlarged ascending aorta surrounding the implanted valved graft was confirmed, and the patient was referred to our department for surgical repair, after which the patient had an uneventful recovery and was discharged home on postoperative day 12.

[Surgical aspects of (cardio) pulmonary transplantation]. / Aspects chirurgicaux de la transplantation (coeur) poumons.

UNLABELLED: INTRODUCTION AND STATE OF THE ART: Both short and long-term outcomes following lung transplantation have improved substantially in recent years as a result of advances in the selection and management of donors, organ preservation, immunosuppressive therapy, and the treatment of infectious and malignant complications. In addition surgical techniques have evolved over time and have contributed to this increase in success rates. PERSPECTIVES AND CONCLUSIONS: This review outlines surgical aspects of lung transplantation including a historical note, techniques of lung harvesting, some anaesthetic considerations, the different transplant types and incisions, as well as anastomotic techniques and their pitfalls.

Prevention of bone loss in cardiac transplant recipients. A comparison of biphosphonates and vitamin D.

Bone mineral density is already abnormally reduced at the moment of cardiac transplantation and bone loss occurs at an impressive rate in the first postoperative year. The aim of the study was to compare two prophylactic medical regimens as to their efficacy in mitigating bone loss after transplantation. Forty-eight consecutive recipients were randomized to receive either alternating calcium carbonate and disodium etidronate (group A) or a daily supplement of calcium carbonate and alphacalcidol (group B). Bone mineral density measurements were performed immediately before hospital discharge and 6, 12, and 24 months after surgery using dual energy X-ray absorptiometry. Clinical events were recorded and roentgenograms of the spine were performed postoperatively and 1 and 2 years later. In both treatment groups bone loss remained significant at the level of the lumbar spine in the first postoperative year (P<0.005) and at the level of the femoral neck in the first (P<0.005) and the second (P<0.06) year after transplantation. Six months after transplantation, however, patients receiving alphacalcidol had a significant reduction in bone loss at the level of the lumbar spine (P=0.047) and at the level of the femoral neck (P=0.043). At the level of the femoral neck this decrease in bone loss was even more pronounced in the second postoperative year (P<0.001). In the group of patients treated with disodium etidronate, 4 recipients needed additional hospitalizations for treatment of symptomatic fractures at the level of the lumbar spine or the femoral neck. No such events happened in recipients receiving vitamin D supplements. Prophylactic administration of calcium carbonate and alphacalcidol after cardiac transplantation reduces bone loss and seems to decrease osteoporotic complications.

Safety and efficacy of low dose simvastatin in cardiac transplant recipients treated with cyclosporine.

Hyperlipidemia is common in heart transplant patients. Lipid-lowering therapy poses special problems, yet may be important because accelerated graft atherosclerosis is the major factor limiting long-term survival. Simvastatin 5 mg/day was started > 6 months after surgery in 26 consecutive cardiac transplant recipients with a total serum cholesterol level of > 250 mg/dl. The dose of simvastatin was increased in 5-mg increments until total serum cholesterol fell below 220 mg/dl or until side effects developed or up to a maximal dose of 20 mg/day. The final average daily dose was 10 mg. Changes in serum lipid levels after 6 months of therapy were compared with data from a matched and concurrent control group of heart transplant patients not taking simvastatin. Immunosuppression for both groups consisted of CsA, AZA, and corticosteroids. In the simvastatin-treated group, the serum level of total cholesterol decreased by 27% from 315 +/- 53 to 230 +/- 38 mg/dl (P < 0.0001), low density lipoprotein cholesterol decreased by 40% from 205 +/- 30 to 123 +/- 32 mg/dl (P < 0.0001), and triglycerides decreased by 21% from 177 +/- 89 to 140 +/- 49 mg/dl (P < 0.01). There was no significant change in high density lipoprotein cholesterol level. Body weight and CsA blood levels remained stable. Steroid intake decreased during the study period to a similar extent in both the treated and the control groups. In the control group, no significant changes in serum lipid levels were observed. Two patients experienced a mild form of myotoxicity. In one other patient simvastatin treatment was stopped after an acute pancreatitis of uncertain etiology developed. Low dose simvastatin effectively lowers total serum cholesterol, low density lipoprotein cholesterol, and triglycerides in heart transplant patients. With due precautions, the safety profile of the drug in this patient population seems reasonable.

Homograft insertion for pulmonary regurgitation after repair of tetralogy of fallot improves cardiorespiratory exercise performance.

Surgical repair of tetralogy of Fallot (TOF) with reconstruction of the right ventricular (RV) outflow tract invariably results in pulmonary regurgitation. Chronic pulmonary regurgitation has been associated with RV dysfunction and decreased exercise performance. The present study assessed the influence of pulmonary valve replacement (PVR) for severe pulmonary regurgitation after previous TOF repair on cardiorespiratory exercise performance and RV function. Eighteen patients, between the ages of 8 and 18 years, underwent an exercise test and a cardiac magnetic resonance imaging scan at least 1 year after PVR. The exercise data were compared with those obtained from 24 age-matched normal controls and 27 age-matched patients with repaired TOF and a moderate degree of pulmonary regurgitation. A subgroup of 11 patients had an exercise test performed before and after PVR. Cardiopulmonary exercise performance was evaluated by determination of the ventilatory anaerobic threshold (VAT) and by the steepness of the slope of oxygen uptake versus exercise intensity (SVO2). After PVR there was a significant increase in VAT (86+/-11% before to 106.9+/-14% after, p = 0.03) and in SVO2 (1.71+/-0.47 to 2.3+/-0.39, p = 0.004). In patients examined after PVR, the VAT and SVO2 values were not significantly different from the values in the normal controls (104+/-15% [p>0.05] and 2.03+/-0.77 after PVR vs. 2.42+/-0.68 [p>0.25], respectively). In contrast, patients with repaired TOF and a moderate degree of pulmonary regurgitation had a significantly lower VAT (86+/-11%, p<0.05) and SVO2 (1.8+/-0.74 vs. 2.42+/-0.68, p<0.05) than normal controls. Magnetic resonance imaging studies revealed residual RV dilatation and dysfunction. However, there was no correlation between RV dilatation and RV dysfunction and aerobic exercise capacity. It is concluded that aerobic exercise capacity substantially improves after PVR for severe pulmonary regurgitation after previous TOF repair. Although the right ventricle remains significantly dilated and hypocontractile, there is no relation between RV function and exercise performance.

The modified polytetrafluoroethylene Blalock-Taussig shunt: case report of an unusual complication.

A case of excessive serous leak through a modified polytetrafluoroethylene Blalock-Taussig shunt is presented. This relatively rare complication was treated successfully with fibrin glue and collagen fleece.

Ultrastructural and cytochemical correlates of myocardial protection by cardiac hypothermia in man.

We report observations on ultrastructural and cytochemical changes in the myocardium after hypothermic protection in 21 patients who underwent cardiac operation. Two general categories of hypothermic protection were studied. (1) topical cooling during anoxic arrest and moderate general hypothermia (10 patients with aortic valve replacement, Group 1) and (2) intermittent perfusion during moderate general hypothermia combined with topical cooling (11 patients with multiple valve replacement, Group II). Transmural left ventricular biopsies were taken at the start of the cardiopulmonary bypass and shortly after the end of aortic cross-clamping. In Group I (cross-clamp time, 51 +/- 12 minutes) only minor pathologic changes of the myocardial fine structure were found, with no differences among the left ventricular layers. In most mitochondria, structure remained intact but the mitochondrial granules disappeared. Cytochrome-c-oxidase activity was unchanged. In Group II (total cross-clamp time, 83 +/- 16 minutes) the subendocardium was well preserved. Slight subcellular damage comparable with that of resulting from topical cooling was seen in all hearts even after a total cross-clamp period of 106 minutes. Cytochrome-c-oxidase activity was unchanged. In the subepicardium, however, a positive correlation was found between the severity of ultrastructural damage and total cross-clamp time (p less than 0.05). Matrix clearing, damage to the cristae and the mitochondrial membranes, and nuclear abnormalities occurred when the aorta was cross-clamped for morethan 60 minutes. Cytochrome-c-oxidase activities decreased in these samples. It is concluded that: (1) no significant subcellular injury was found in hearts cooled topically during 1 hour of anoxic arrest; and (2) in hearts protected by intermittent perfusion during moderate general hypothermia and additional external cooling, the subendocardium was well preserved for anoxic periods of up to 106 minutes. However, after 60 minutes of aortic cross-clamping subcellular damage increased progressively in the subepicardium.

The Björk-Shiley Monostrut valve. Clinical experience in 647 patients.

A total of 647 consecutive patients underwent valve replacement with a Björk-Shiley Monostrut valve (Shiley, Inc., Irvine, Calif.) from January 1, 1984, through December 31, 1988. A total of 135 patients (20.8%) had had a previous cardiac correction. Overall hospital mortality was 6.8%. Preoperative functional class, cardiopulmonary bypass time, aortic crossclamping time, and cause of valve replacement influenced in-hospital mortality significantly (univariate analysis). The median follow-up was 30 months. Overall actuarial survival was 81% +/- 4% at 6 years. Univariate and multivariate regression analysis showed that preoperative functional class, total cardiopulmonary bypass time, size of mitral prosthesis, and pure mitral insufficiency significantly influenced total mortality after valve replacement. Additional coronary bypass grafting and redo valve replacement did not. The actuarial rate of freedom from thromboembolism was 86% +/- 4% at 6 years. There were no cases of valve thrombosis. Patients having a thromboembolic event showed a higher probability of late death after native valve replacement.

Mechanical support with microaxial blood pumps for postcardiotomy left ventricular failure: can outcome be predicted?

OBJECTIVE: We sought to identify the indications of mechanical support in postcardiotomy left ventricular failure in patients who are unable to undergo transplantation. METHODS: From 1989 through 1997, 61 patients with postcardiotomy left ventricular failure beyond intra-aortic balloon pumping were assisted with the Hemopump cardiac assist system (Medtronic, Minneapolis, Minn). Their mean age was 64 +/- 8 years. Comorbidity was prevalent; 47% underwent cardiac massage before pump support, and evolving myocardial infarction was diagnosed in 43% before surgery. Multivariable logistic regression of data known at the moment of pump insertion was performed to identify the risk factors for mortality. RESULTS: Sixty-five percent of the patients were weaned from the device, but only 30% were discharged home. Cardiac index evolution during the first hours after pump insertion (P <.001) is the only independent predictor for possibility to wean from the device in the multivariable analysis. Acute renal failure is the only variable retained in the model for 90-day mortality. Device-related complications were far more frequent with the femoral (54%) than with the transthoracic (6%) cannula. Only 13% of the patients had bleeding complications. CONCLUSIONS: One third of the patients with postcardiotomy heart failure refractory to use of the intra-aortic balloon pump can be saved with the use of an endovascular axial flow pump. It is impossible to predict lethal outcome on preoperative data alone. The early hemodynamic response to support seems to be related to functional recovery of the heart and subsequent weaning from the device.

Nifedipine as an adjunct to St. Thomas' Hospital cardioplegia. A double-blind, placebo-controlled, randomized clinical trial.

The cardioprotective effect of the addition of the slow calcium-channel blocker nifedipine to cardioplegic solution was tested in two double-blind placebo controlled randomized studies. The first study included 24 patients undergoing aortic-coronary bypass grafting, and the second included 24 patients undergoing aortic valve replacement. Nifedipine at a dose of 200 micrograms/L or placebo was added to St. Thomas' Hospital cardioplegic solution. The following markers of ischemia were used: adenosine triphosphate and its catabolites, creatine phosphate and inorganic phosphate, determined in transmural left ventricular biopsy specimens taken before, at the end of, and after aortic cross-clamping; hemodynamic recovery 15 minutes after cessation of cardiopulmonary bypass; clinical outcome in terms of the incidence of arrhythmias, low cardiac output, positive inotropic support immediately after operation, and follow-up at 15 months. The main difference between the two studies was that myocardial temperature during cross-clamping remained constant at 14 degrees C in coronary bypass grafting but increased to 25 degrees C in valve operations despite the application of the same amounts of cardioplegic solutions. This lower temperature resulted in better preservation of high-energy phosphates in coronary bypass operations as compared to the placebo group having valve replacement operations. According to analysis of variance, a drug effect could be demonstrated only in the aortic valve replacement study: Accumulation of breakdown products of the adenine nucleotide pool was less in the nifedipine group than in the placebo group (p less than 0.05). Adenosine triphosphate decreased only to 84% in the nifedipine group and to 72% in the placebo group. Despite this adenosine triphosphate-sparing effect, weaning from cardiopulmonary bypass was more difficult in the nifedipine group. Left ventricular stroke work index 15 minutes after bypass was decreased to 72% of the prebypass value in the nifedipine group (t test, p less than 0.01) and only to 86% in the placebo group (p = NS). In contrast, after the patients were admitted to the intensive care unit, the incidence of low cardiac output tended to be lower in the nifedipine group than in the placebo group: 33% versus 58% (p = NS). In conclusion, ischemia-induced degradation of nucleotides as it occurs when myocardial cooling is inadequate can be prevented by the addition of nifedipine to the St. Thomas' Hospital cardioplegic solution. This effect, however, is not associated with an improved clinical outcome.

Structural valve deterioration in mitral replacement surgery: comparison of Carpentier-Edwards supra-annular porcine and perimount pericardial bioprostheses.

BACKGROUND: Bioprostheses preserved with glutaraldehyde, both porcine and pericardial, have been available as second-generation prostheses for valve replacement surgery. The performance with regard to structural valve deterioration with the Carpentier-Edwards supra-annular (CE-SAV) porcine bioprosthesis and the Carpentier-Edwards Perimount (CE-P) pericardial bioprosthesis (Baxter Healthcare Corp, Edwards Division, Santa Ana, Calif) was evaluated to determine whether there was a difference in mitral valve replacement. METHODS: The CE-SAV bioprosthesis was implanted in 1266 overall mitral valve replacements (isolated mitral, 1066; mitral in multiple, 200) and the CE-P bioprosthesis in 429 overall mitral valve replacements (isolated mitral, 328; mitral in multiple, 101). The mean age of the CE-SAV population was 64.2 +/- 12.2 years and that of the CE-P population, 60.7 +/- 11.7 years (P =.0001). For the study, structural valve deterioration was diagnosed at reoperation for explantation. RESULTS: The freedom from structural valve deterioration was evaluated to 10 years, and the freedom rates reported are at 10 years. For the overall mitral valve replacement groups, the actuarial freedom from deterioration was significant (P =.0001): CE-P > CE-SAV for 40 years or younger, 80% versus 60%; 41 to 50 years, 91% versus 61%; 51 to 60 years, 84% versus 69%; 61 to 70 years, 95% versus 75%. The older than 70-year group was 100% versus 92% (no significant difference). The actual freedom from structural valve deterioration also demonstrated the same pattern at 10 years: 40 years or younger, CE-P 82% versus CE-SAV 68%; 41 to 50 years, 92% versus 70%; 51 to 60 years, 90% versus 80%; 61 to 70 years, 97% versus 88%; and older than 70 years, 100% versus 97%. The independent risk factors of structural valve deterioration for the overall mitral valve replacement group were age and age groups and prosthesis type (CE-SAV > CE-P). The prosthesis type either in isolated replacement or in multiple replacement was not predictive of structural valve deterioration. The pathology of structural valve deterioration was different: 70% of CE-P failures were due to calcification and 57% of CE-SAV failures were due to combined calcification and leaflet tear. CONCLUSION: The actuarial and actual freedom from structural valve deterioration, diagnosed at reoperation, is greater at 10 years for CE-P than for CE-SAV bioprostheses. The mode of failure is different, and the cause remains obscure. Long-term evaluation is recommended, because the different modes of failure may alter the clinical performance by 15 and 20 years.

Phrenic nerve dysfunction after heart-lung and lung transplantation.

BACKGROUND: Phrenic nerve dysfunction (PND) is a well-known complication after cardiac surgery, but reports on its incidence and consequences after heart-lung and lung transplantation are scarce. METHODS: The incidence and consequences (ventilator days and intensive-care unit length of stay [ICU LOS]) of PND were studied by retrospective chart review of 27 heart-lung (HLTx) and 111 lung (LTx) transplantations performed from July 1991 to June 2001 at the Leuven University Hospital, Leuven, Belgium. On clinical suspicion of diaphragmatic dysfunction, nerve conduction studies were performed, which were completed with a needle electromyogram (EMG) of the diaphragm when the conduction study was non-conclusive. RESULTS: The incidence of PND in 21 evaluable HLTx recipients was 42.8% (9 of 21 patients), resulting in significantly more ventilator days for PND patients (37.6 +/- 36.3 days vs 5.3 +/- 3 days; p < 0.05) and a prolonged ICU LOS (46.8 +/- 33 vs 9.8 +/- 4.9 days; p < 0.05). In the 97 evaluable LTx patients, 9.3% (9 of 97 patients) developed PND. This resulted in more ventilator days for the PND group (30.6 +/- 14.8 days vs non-PND 7.9 +/- 14.8 days. p < 0.05) and a longer ICU LOS (PND 37.8 +/- 18.7 days vs non-PND 12.1 +/- 17.8 p < 0.05). Needle EMG of the diaphragm revealed denervation in 1 HLTx and 5 LTx patients. In LTx patients sustaining PND more tracheostomies were performed (44.4% vs 4.5% for non-PND patients p < 0.005). Eight of 9 LTx patients with PND had sequential single-lung transplantation. CONCLUSIONS: PND represents an important clinical problem after HLTx and LTx and has a considerable influence on both number of ventilator days and ICU resource utilization.

Hemopump fails as bridge to transplantation in postinfarction ventricular septal defect.

From 1990, six patients were bridged to transplantation with a catheter-mounted axial flow pump (Hemopump). Indications were graft failure (two patients), postinfarction ventricular septal defect (two patients), myocarditis (1 patient), and myocardial infarction (1 patient). The 21F cannula, inserted via the groin, was used as a partial assist in four patients, and the 31F cannula, inserted via the ascending aorta, was used to assist the other two patients completely. Hemodynamic recovery was achieved in all patients (mean cardiac index rose from 2.1 L/gm/m2 to 3.85 L/gm/m2 after 1 hour assist). Sudden pump failure occurred in the two patients with postinfarction ventricular septal defect and a piece of necrotic tissue blocking the catheter was found. Both patients died. The other four patients were successfully bridged to transplantation. One of these patients died during his postoperative hospital stay; the three remaining patients were discharged and were well at follow-up (46, 40, and 3 months). The Hemopump device provides sufficient organ perfusion to be used as a bridge to transplantation. No conclusions can be drawn for the long-term use (longest run in this series was 102 hours). Postinfarction ventricular septal defect is a contraindication for the use of the Hemopump device.

Dobutamine stress echocardiography after heart transplantation.

Dobutamine stress echocardiography was performed in 28 heart transplant recipients to study its value in the detection and staging of transplant vasculopathy. Fourteen patients had angiographic evidence of coronary artery disease (group 1), and 14 had angiographically normal coronary arteries (group 2). The dobutamine stress protocol called for a dose increase of dobutamine every 3 minutes until the age-predicted maximal heart rate was achieved. In groups 1 and 2, the mean maximal dose of dobutamine was, respectively, 24 +/- 9 micrograms/kg min and 29 +/- 8 micrograms/kg min, and the mean rate-pressure product was, respectively, 12386 +/- 1777 mm Hg/min and 10753 +/- 1085 mm Hg/min at rest, increasing to 20987 +/- 4020 mm Hg/min and 19795 +/- 2728 mm Hg/min at maximal dose. No patient in group 1 or 2 had deterioration of global or regional wall motion under dobutamine stress. In group 1, seven patients had wall motion abnormalities at rest, normalizing in five of them under dobutamine stress. In group 2, four patients had wall motion abnormalities at rest, normalizing in all patients under dobutamine stress. Consequently, this protocol of dobutamine stress echocardiography is unsuitable for the early detection of transplant vasculopathy despite its proven value in the general population. Conversely, these data suggest that the functional sequelae of transplant vasculopathy are not necessarily prominent, despite the known angiographic underestimation of the extent of the disease.

Late acute rejection and subclinical noncompliance with cyclosporine therapy in heart transplant recipients.

BACKGROUND: Although noncompliance with immunosuppressive medication is recognized as a critical behavioral risk factor for late acute rejection episodes and graft loss after transplantation, little is known about the degree of subclinical cyclosporine noncompliance, its associated risk for acute late rejection episodes (>1 year after transplantation), and its determinants in heart transplant recipients. METHODS: The convenience sample of this longitudinal study included 101 European heart transplant recipients (87 men and 14 women), with a median age of 56 (Q1 = 50, Q3 = 61) and a median posttransplantation status of 3 (range 1 to 6) years. Subclinical cyclosporine noncompliance was measured during a 3-month period with electronic event monitoring. Selected sociodemographic, behavioral, cognitive, emotional, health, and treatment-related determinants of medication noncompliance were measured by using instruments with established psychometric properties or by patient interviews. With the use of iterative partitioning methods of cluster analysis, including nonstandardized electronic event monitoring compliance parameters, patients were categorized by degree of subclinical cyclosporine noncompliance into a 3-cluster solution. RESULTS: Overall compliance was high, with a median medication taking compliance of 99.4%. The 3 derived clusters, that is, excellent compliers (84%), minor subclinical noncompliers (7%), and moderate subclinical noncompliers (9%), differed significantly by degree of subclinical noncompliance (p < .0001) and showed a 1.19%, 14.28%, and 22.22% incidence of late acute rejections (p = .01), respectively. The 3 groups also differed in terms of former medication noncompliance (p = .02), appointment noncompliance (p = .03), and perceived self-efficacy with medication taking (p = .04). CONCLUSIONS: Although in absolute numbers cyclosporine compliance in this sample was high, minor deviations from dosing schedule were associated with an increased risk for acute late rejection episodes. This suggests a pivotal role of patient compliance in successful long-term outcome after transplantation.