Preliminary experience with inhaled milrinone in cardiac surgery

Background: Inhaled administration of milrinone reduces pulmonary artery pressure. Pulmonary hypertension (PH) and right heart failure are associated with difficult separation from cardiopulmonary bypass (CPB). Therefore, inhaled milrinone could facilitate separation from CPB. Objective: To determine the impact and timing of administration of inhaled milrinone. Methods: A retrospective analysis of our experience on high-risk patients receiving inhaled milrinone was conducted to evaluate the postoperative course after administration of the drug. Results: Seventy-three patients received inhaled milrinone from June 2002 to February 2005. Mean age was 64 ± 13 years, with a mean preoperative Parsonnet score of 27 ± 14. Inhaled milrinone (5 mg) was administered before (n = 30) or after (n = 40) CPB, three patients had off-pump procedures and were excluded. CPB time was 145 ± 78 min with cross-clamping times of 91 ± 56 min without any significant difference between groups. Fifty-four patients (74%) had difficult separation from CPB, 14 patients (19%) required an intra-aortic balloon pump and 10 patients (14%) needed emergency reinitiation of CPB for hemodynamic instability. Ten patients died in the perioperative period (13.7%). Patients receiving inhaled milrinone prior to CPB initiation had a lowering pulmonary artery pressure after CPB (p < .01) and had less emergency reinitiation of CPB after weaning (3% vs 23%, p = .02) as compared to those with administration after CPB. No detectable side effects were directly linked to the administration of the drug. Conclusion: In this high-risk cohort, use of inhaled milrinone was well tolerated. Administration before initiation of CPB could help weaning from CPB.     

Fate of pulmonary arteries following Norwood Procedure

Objective: This study evaluated the requirement for surgical reoperation and catheter-based reintervention to central pulmonary arteries (CPAs) following Norwood Procedure (NP). We sought to identify the influence of various surgical techniques employed during NP on subsequent interventions. Methods: Between 1993 and 2004, 226 patients underwent Stage II following NP. Ninety-eight patients (43%) had completion of Fontan circulation (Stage III) and a further 107 (47%) are on course for Fontan completion with 21 (9%) inter-stage deaths. During NP, the aortic arch was reconstructed without additional material (n = 91, 40%) or with a pulmonary homograft patch (n = 135, 60%). Pulmonary blood flow was supplied by modified Blalock–Taussig shunt (n = 177, 78%) or right ventricle to pulmonary artery conduit (RV-PA; n = 49, 22%). The CPAs defect was closed directly (n = 69, 31%) or with a patch (n = 157, 69%). Complete resection of coarctation was performed in 126 patients (56%). Results: Ninety-seven patients (43%) required surgical reoperation to CPAs during Stage II. Actuarial freedom from reoperation was 60 ± 3%, 52 ± 4% and 50 ± 4% at 1, 5 and 10 years, respectively. On multivariable analysis, NP with RV-PA increased risk of reoperation (LR 8.3, 5.3–13.2; p < 0.001). Forty-one patients (18%) required catheter-based reintervention on CPAs. Actuarial freedom from reintervention was 98 ± 1%, 72 ± 4% and 58 ± 6% at 1, 5 and 10 years, respectively. CPA problems were almost exclusively limited to the proximal Left pulmonary artery. On multivariable analysis, catheter-based reintervention became more common with time. Complete resection of coarctation increased risk of reintervention (LR 3.9, 1.6–9.6; p < 0.005). Arch reconstruction and CPAs repair techniques did not affect risk of reoperation or reintervention on CPAs. Conclusions: CPA stenoses and hypoplasia need surgical attention in approximately half of all patients undergoing the NP. The need for reoperation is increased when using the RV-PA conduit technique (although the majority of these are performed as part of the Stage II procedure). Catheter reinterventions are almost exclusively confined to the left CPA and are increased when the arch is shortened by resection of the coarctation tissue at time of NP.     

Jugular venous valved conduit (Contegra) matches allograft performance in infant truncus arteriosus repair

Objective: Limited availability and durability of allograft conduits require that alternatives be considered. We compared bovine jugular venous valved (JVV) and allograft conduit performance in 107 infants who survived truncus arteriosus repair. Methods: Children were prospectively recruited between 2003 and 2007 from 17 institutions. The median z-score for JVV (n = 27, all 12 mm) was +2.1 (range +1.2 to +3.2) and allograft (n = 80, 9–15 mm) was +1.7 (range −0.4 to +3.6). Propensity-adjusted comparison of conduit survival was undertaken using parametric risk-hazard analysis and competing risks techniques. All available echocardiograms (n = 745) were used to model deterioration of conduit function in regression equations adjusted for repeated measures. Results: Overall conduit survival was 64 ± 9% at 3 years. Conduit replacement was for conduit stenosis (n = 16) and/or pulmonary artery stenosis (n = 18) or regurgitation (n = 1). The propensity-adjusted 3-year freedom from replacement for in-conduit stenosis was 96 ± 4% for JVV and 69 ± 8% for allograft (p = 0.05). The risk of intervention or replacement for branch pulmonary artery stenosis was similar for JVV and allograft. Smaller conduit z-score predicted poor conduit performance (p < 0.01) with best outcome between +1 and +3. Although JVV conduits were a uniform diameter, their z-score more consistently matched this ideal. JVV exhibited a non-significant trend towards slower progression of conduit regurgitation and peak right ventricular outflow tract (RVOT) gradient. In addition, catheter intervention was more successful at slowing subsequent gradient progression in children with JVV versus those with allograft (p < 0.01). Conclusions: JVV does match allograft performance and may be advantageous. It is an appropriate first choice for repair of truncus arteriosus, and perhaps other small infants requiring RVOT reconstruction.     

The effects of therapeutic sulfide on myocardial apoptosis in response to ischemia–reperfusion injury

Objective: Ischemia–reperfusion (I/R) injury, often encountered clinically, results in myocardial apoptosis and necrosis. Hydrogen sulfide (H₂S) is produced endogenously in response to ischemia and thought to be cardioprotective, although its mechanism of action is not fully known. This study investigates cardioprotection provided by exogenous H₂S, generated as sodium sulfide on apoptosis following myocardial I/R injury. Methods: The mid-LAD coronary artery in Yorkshire swine (n = 12) was occluded for 60 min, followed by reperfusion for 120 min. Controls (n = 6) received placebo, and treatment animals (n = 6) received sulfide 10 min prior to and throughout reperfusion. Hemodynamic, global, and regional functional measurements were obtained. Evans blue/TTC staining identified the area-at-risk (AAR) and infarction. Serum CK-MB, troponin I, and FABP were assayed. Tissue expression of bcl-2, bad, apoptosis-inducing-factor (AIF), total and cleaved caspase-3, and total and cleaved PARP were assessed. PAR and TUNEL staining were performed to assess apoptotic cell counts and poly-ADP ribosylation, respectively. Results: Pre-I/R hemodynamics were similar between groups. Post-I/R, mean arterial pressure (mmHg) was reduced by 30.2 ± 4.3 in controls vs 8.2 ± 6.9 in treatment animals (p = 0.01). +LV dP/dt (mmHg/s) was reduced by 1308 ± 435 in controls vs 403 ± 283 in treatment animals (p = 0.001). Infarct size (% of AAR) in controls was 47.4 ± 6.2% vs 20.1 ± 3.3% in the treated group (p = 0.003). In treated animals, CK-MB and FABP were lower by 47.0% (p = 0.10) and 45.1% (p = 0.01), respectively. AIF, caspase-3, and PARP expression was similar between groups, whereas cleaved caspase-3 and cleaved PARP was lower in treated animals (p = 0.04). PAR staining was significantly reduced in sulfide treated groups (p = 0.04). TUNEL staining demonstrated significantly fewer apoptotic cells in sulfide treated animals (p = 0.02). Conclusions: Sodium sulfide is efficacious in reducing apoptosis in response to I/R injury. Along with its known effects on reducing necrosis, sulfide's effects on apoptosis may partially contribute to providing myocardial protection. Exogenous sulfide may have therapeutic utility in clinical settings in which I/R injury is encountered.     

Factors affecting early and long-term outcomes after completion pneumonectomy

Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.     

Iloprost improves hemodynamics in patients with severe chronic cardiac failure and secondary pulmonary hypertension

PURPOSE: Significant pulmonary hypertension is a predictor of postoperative right heart insufficiency and increased mortality in patients undergoing orthotopic heart transplantation. Since the use of iv vasodilators is limited by their systemic effects, we evaluated the pulmonary and systemic hemodynamic effects of inhaled aerosolized iloprost (IP) in heart transplant candidates with elevated pulmonary vascular resistance (PVR). METHODS: Twenty-nine male heart transplant candidates because of dilated or ischemic cardiomyopathy with elevated PVR were included in the study. After assessing baseline hemodynamics, 50 micro g aerosolized IP were administered by inhalation. RESULTS: Inhalation of iloprost reduced PVR index (PVRI; 416 +/- 180 vs 349 +/- 173 dyn x sec(-1) x m(-2) x cm(-5); P < 0.01) and mean pulmonary artery pressure (MPAP; 28.6 +/- 9 vs 24.2 +/- 9.1 mmHg; P < 0.01), but did not affect blood pressure or systemic vascular resistance. An additional improvement of ventricular performance with an increase of cardiac index (CI; 2.8 +/- 0.7 vs 2.6 +/- 0.7 L x min(-1) x m(-2); P < 0.05) and a decrease of pulmonary capillary wedge pressure (PCWP; 15.6 +/- 6.8 vs 12.8 +/- 7.1 mmHg; P < 0.01) was observed after inhalation of IP. CONCLUSIONS: Inhaled aerosolized iloprost effectively reduces MPAP and is accompanied by an increase in CI and stroke index. Further advantages of iloprost inhalation are the lack of adverse reactions and ease of administration. Iloprost may be a useful drug to screen for vascular reactivity in cardiac transplantation patients.     

Prognostic value of FDG uptake in early stage non-small cell lung cancer

Background: Non-small cell lung cancer (NSCLC) has a poor prognosis even for early stages of the disease (stage I and II). We studied the prognostic value of PET FDG in patients with completely resected stage I and II NSCLC. Methods: Retrospective study of 96 patients with NSCLC whose staging included ¹⁸F-FDG PET (fluoro deoxy glucose positron emission tomography). Histopathological stage was either stage I (75) or stage II (n = 21). FDG uptake was measured as maximal standardized uptake value for body weight (SUVmax). Mean follow-up was 45 ± 30 months (1–142 months). Overall and cancer-free survival rates were recorded. Results: SUVmax were higher for stage II than for stage I (10.5 ± 4.5 vs 8.5 ± 5, p = 0.04). Mean tumor volumes were equivalent for both stages (33 cm³, p = 0.18), excluding a partial volume effect. The median SUVmax in the whole study population was 7.8. The median survival was significantly longer in patients with a lower (SUVmax ≤ 7.8) FDG uptake (127 months vs 69 months, p = 0.001). For stage I tumors (n = 75), high FDG uptake was significantly associated with reduced median survival: 127 months if SUVmax ≤ 7.8 and 69 months if SUVmax > 7.8 (p = 0.001). For stage II tumors (n = 21), no statistical difference was observed: 72 months vs 40 months for SUVmax ≤ 7.8 and for SUVmax > 7.8, respectively (p = 0.11), although there was a clear trend towards reduced survival for highly metabolic tumors. Disease-free survival was also significantly better for lower metabolic tumors: 96.1 months vs 87.7 months (p = 0.01). Conclusion: High FDG uptake is associated with reduced overall survival and disease-free survival of patients with completely resected stage I–II NSCLC. Whether patients with highly metabolic tumors should undergo a closer postoperative surveillance or adjuvant chemotherapy has to be addressed in a properly designed prospective trial.     

Assessment of pulmonary function after lobectomy for lung cancer — upper lobectomy might have the same effect as lung volume reduction surgery

Objective: Lung volume reduction surgery (LVRS) in well-selected patients with severe emphysema results in postoperative improvement in symptoms and pulmonary function. Experience with LVRS suggests that predicted postoperative FEV_1.0 may be underestimated after lobectomy in patients with lung cancer and emphysema. As most of the patients with lung cancer have more or less emphysematous changes in the lungs, we assumed that lobectomy would achieve the same effect as LVRS even in patients without chronic obstructive pulmonary disease on the pulmonary function test. We assessed changes in pulmonary function in terms of ‘volume reduction effect’ after lobectomy for lung cancer. Methods: Forty-three patients underwent right upper lobectomy (RUL), 38 patients left upper lobectomy (LUL), 39 patients right lower lobectomy (RLL), and 38 patients left lower lobectomy (LLL). Pulmonary function tests were performed preoperatively and 6 months to 1 year after surgery. Results: Percent change in FEV_1.0 after lobectomy was −6.9 ± 16.1% in RUL group, −11.2 ± 16.9% in LUL group, −14.7 ± 9.8% in RLL group, and −12.8 ± 9.5% in LLL group. We evaluated the correlation between a preoperative FEV_1.0% of predicted and percentage change in FEV_1.0 after lobectomy. There were no significant relationships between these variables in RLL or LLL group. In contrast, there were significant negative relationships between these variables in RUL and LUL groups. Correlation coefficients were r = −0.667, p < 0.0001 for RUL and r = −0.712, p < 0.0001 for LUL. In RUL and LUL groups, patients with a higher preoperative FEV_1.0% of predicted had a more adverse percentage change in FEV_1.0 after surgery. In addition, all 13 patients with a preoperative FEV_1.0% of predicted <60% in RUL and LUL groups had an increase in FEV_1.0 postoperatively. Patients with a lower preoperative FEV_1.0% of predicted had a greater ‘volume reduction effect’ with an increase in FEV_1.0 after upper lobectomy. Conclusion: Upper lobectomy might have a volume reduction effect.     

Retrograde flush following topical cooling is superior to preserve the non-heart-beating donor lung

Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex^® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm⁻⁵) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH₂O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH₂O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.     

Systematic mediastinal lymphadenectomy does not increase postoperative immune response after major lung resections

Objective: To assess the influence of mediastinal lymphadenectomy on postoperative concentration of interleukin 6 (IL-6) and interleukin 1 receptor antagonist (IL-1ra) in serum, sputum, and pleural fluid, in patients operated upon due to lung cancer and benign pulmonary diseases. Methods: Thirty-three patients undergoing uncomplicated resections, including 23 with lung cancer and 10 with benign diseases, were analyzed. In patients with right lung cancer we performed a systematic lymphadenectomy, while in patients with left lung cancer systematic sampling was performed. Serum IL-6 and IL-1ra concentration was measured before and after surgery, and on postoperative days 1, 3, and 7, as well as in sputum at the end of surgery and in pleural fluid on postoperative day 1, by ELISA test. Results: In 23 patients with cancer, 19.0 ± 11.43 mediastinal lymph nodes were removed (in 11 patients with right lung cancer 27.6 ± 7.6 and in 12 patients with left lung cancer 11.1 ± 8.1). No differences were found in serum and sputum concentration of IL-6 and IL-1ra between patients after right and left thoracotomy due to cancer and between patients with cancer and patients with benign diseases. Patients with cancer had a lower concentration of IL-1ra in pleural fluid (median 16950, range 16050–45470.05 pg/ml) than patients with benign diseases (76665.6 pg/ml (range 53618–89617.9); p = 0.0008). In 23 cancer patients a negative correlation between concentration of cytokines in pleural fluid and a number of mediastinal lymph nodes resected was observed (Spearman correlation coefficient for IL-6: r = −0.44, p = 0.04; for IL-1ra: r = −0.57, p = 0.01). Such correlation was not observed for a number of positive N2 lymph nodes. Conclusions: Systematic lymphadenectomy added to major lung resection does not increase postoperative humoral immune response in uncomplicated cases, as measured by levels of IL-6 and IL-1ra in serum, pleural fluid, and sputum.     

Long-term experiences on cardiac retransplantation in adults

Background: It remains disputed whether cardiac retransplantation should be performed. This study aimed to evaluate our long-term experiences on cardiac retransplantation in adults. Patients and methods: Between March 1989 and December 2004, 2% (28/1290) of cardiac retransplantations were performed. Results: The reasons for cardiac retransplantation were cardiac allograft vasculopathy (n = 13; 47%), primary graft failure (n = 11; 39%), and refractory acute rejection (n = 4; 14%). The 30-day mortality risk was 29% (acute rejection: 50%; primary graft failure: 36%; cardiac allograft vasculopathy: 15%, p = 0.324), compared to 8.5% for primary cardiac transplantation (p < 0.001). The causes of early death were acute rejection (n = 3; 37%), multiorgan failure (n = 3; 37%), primary graft failure (n = 1; 13%), and right ventricular failure (n = 1; 13%). The late mortality rate was 96/1000 patient-years. The causes of late death were acute rejection (n = 4; 50%), cardiac allograft vasculopathy (n = 2; 25%), multiorgan failure (n = 1; 13%), and infection (n = 1; 13%). The 1-, 5-, 10-, and 15-year survival was respectively 78, 68, 54, and 38% (primary cardiac transplantation), and 46, 41, 32, and 32% (cardiac retransplantation) (p = 0.003). The short-term survival for cardiac retransplantation due to cardiac allograft vasculopathy was likely better than primary graft failure and refractory acute rejection (p = 0.09). Conclusion: The overall outcomes of cardiac retransplantation are significantly inferior to primary cardiac transplantation. Cardiac retransplantation should be only performed for selected patients.     

Clinical advantages of using mini-bypass systems in terms of blood product use, postoperative bleeding and air entrainment: an in vivo clinical perspective

Objective: In an effort to minimize the effect of extracorporeal circulation (ECC), mini-bypass is gaining clinical acceptance in routine coronary artery bypass grafting (CABG). These small circuits target combine the clinical advantages of reduced prime, 100% bio-coating and suction blood separation. We demonstrate that the use of mini-bypass in routine CABG reduces homologous blood product use and postoperative bleeding. Our goal was to also demonstrate that these small systems are effective in gaseous microemboli (GME) management as compared to a conventional extracorporeal system. Methods: Prospective, randomized study comparing 30 mini-bypass (Dideco ECC.O™) to 30 conventional systems (n = 30, Dideco 903 Avant™). Study included CABG cases only, independent of preoperative coagulative status; clinic ethical committee approval and informed patient consent was obtained before initiating study. Results: There were no statistical differences in terms of patient demographics. Statistically significant differences were seen in transfusion frequency (27% of the study group vs 43% in the control group, p = 0.05), transfused volume (133.3 ± 244.5 ml vs 325 ± 483.1 ml, p < 0.05), fresh frozen plasma (0 unit vs 3 units, p < 0.001), postoperative bleeding (301.8 ± 531.9 ml vs 785.5 ± 1000.4 ml, p < 0.05) and GME activity post-arterial filter (0.14 μl vs 5.32 μl, p < 0.05). Conclusions: The adoption of mini-bypass significantly potentially reduces hemodilution, donor blood usage, postoperative bleeding and exposure to GME in routine CABG patients as compared to the use of conventional extracorporeal circulation circuits.     

Inhaled iloprost in patients with chronic thromboembolic pulmonary hypertension: effects before and after pulmonary thromboendarterectomy

BACKGROUND: In primary pulmonary hypertension, aerosolized prostanoids selectively reduce pulmonary vascular resistance and improve right ventricular function. In this study, hemodynamic effects of inhaled iloprost, a stable prostacyclin analogue, were evaluated in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and early after pulmonary thromboendarterctomy (PTE). METHODS: Ten patients (mean age 49 years old [32 to 70 years old], New York Heart Association functional class III and IV) received a dose of 33 micro g aerosolized iloprost immediately before surgery (T1), after intensive care unit admission (T2), and 12-hours postoperatively (T3). Effects on pulmonary and systemic hemodynamics and gas exchange were recorded and compared with preinhalation baseline values. RESULTS: Preoperatively, inhaled iloprost did not significantly change mean pulmonary artery pressure (mPAP), cardiac index (CI), or pulmonary vascular resistance (PVR). Postoperatively, inhaled iloprost induced a significant reduction of mPAP and PVR and a significant increase of CI at T2 and T3. Preinhalation versus postinhalation PVR was as follows: at T1, 847 versus 729 dynes. s. cm(-5), p = 0.45; at T2, 502 versus 316 dynes. s. cm(-5), p = 0.008; and at T3, 299 versus 227 dynes. s. cm(-5), p = 0.004. CONCLUSIONS: In patients with CTEPH, inhalation of iloprost elicits no significant pulmonary vasodilation before surgery, and may have detrimental effects on systemic hemodynamics. Postoperatively, it significantly reduces mPAP and PVR, and enhances CI. Following PTE, inhalation of iloprost is useful to improve early postoperative hemodynamics.     

Inhaled aerosolized iloprost in the evaluation of heart transplant candidates--experiences with 45 cases

PURPOSE: Pulmonary hypertension represents a significant predictor of postoperative right heart insufficiency and increased mortality in patients undergoing orthotopic heart transplantation. As the use of intravenous vasodilators is limited by their systemic effects, we evaluated the pulmonary and systemic hemodynamic effects of inhaled aerosolized iloprost in heart transplant candidates with elevated pulmonary vascular resistance. METHODS: Forty-five male heart transplant candidates with dilated or ischemic cardiomyopathy were included in the study. After assessing baseline hemodynamics, 20 microg of aerosolized iloprost was administered by ultrasonic inhalation. All patients were breathing spontaneously. RESULTS: Inhalation of iloprost reduced pulmonary vascular resistance index (395 +/- 205 vs 327 +/- 222 dyne.s.cm(-5).m(-2); P < 0.05) and mean pulmonary arterial pressure (28.7 +/- 10 vs 24.3 +/- 10 mm Hg; P < 0.05). An additional improvement of ventricular performance with an increase of cardiac index (2.7 +/- 0.7 vs 3.0 +/- 0.8 L.min(-1).m(-2); P < 0.05) and a decrease of pulmonary capillary wedge pressure (16.6 +/- 7.7 vs 13.4 +/- 7.3 mm Hg; P < 0.05) was accompanied by a slight decrease of systemic vascular resistance (1280 +/- 396 vs 1172 +/- 380 dyne.s.cm(-5); P < 0.05). However, the mean arterial pressure remained uninfluenced. CONCLUSIONS: Inhaled aerosolized iloprost effectively reduces mean pulmonary arterial pressure and also induces an increase in cardiac index. Further advantages of iloprost inhalation are the lack of adverse reactions and ease of administration. Iloprost represents a useful drug to screen for vascular reactivity in cardiac transplantation patients.     

Effects of pre-natal and early post-natal undernutrition on adult internal thoracic artery function

Objective: Previous studies in humans and animals have suggested that undernutrition in utero and in early post-natal life may lead to altered vascular function in a number of peripheral arteries. We investigated the effect of pre- and post-natal nutrient restriction on the vascular reactivity of the left internal thoracic artery using a sheep model. Methods: Welsh mountain ewes were mated and assigned to three dietary groups: (1) 100% of total nutritional requirements (control, n = 6); (2) 50% of total nutritional requirements during the first 31 days of gestation (n = 6); and (3) 50% nutritional restriction during the first 31 days of gestation, followed by a restriction in the diet of their offspring 12–25 weeks post-natally, designed to produce a 15% reduction in growth trajectory (n = 7). The male offspring were sacrificed at 130 weeks; the left internal thoracic artery was mounted onto a wire myograph and the reactivity of the vessel to various agonists measured. Results: The offspring of animals who underwent an early gestation nutrient restriction had a significantly increased basal tone (0.41 ± 0.25 vs 6.34 ± 1.35, p = 0.015) and sensitivity to phenylephrine (log EC₅₀: −6.23 ± 0.04 M vs −5.74 ± 0.17 M, p = 0.036) as compared with control animals. However, this phenomenon was not seen in animals that underwent both pre- and post-natal nutrient restriction. Conclusions: Pre-natal undernutrition increases the basal tone and sensitivity of the left internal thoracic artery to phenylephrine. This effect is significantly attenuated by continued undernutrition in early post-natal life. These experiments suggest that in utero and early post-natal undernutrition may be important determinants of graft function in later life.     

Risk factors for reoperation after relief of congenital subaortic stenosis

Background: Congenital subaortic stenosis entails a lesion spectrum, ranging from an isolated obstructive membrane, to complex tunnel narrowing of the left outflow associated with other cardiac defects. We review our experience with this anomaly, and analyze risk factors leading to restenosis requiring reoperation. Methods: From 1994 to 2006, 58 children (median age 4.3 years, range 7 days–13.7 years) underwent primary relief of subaortic stenosis. Patients were divided into simple lesions (n = 43) or complex stenosis (n = 15) associated with other major cardiac defects. Age, pre- and postoperative gradient over the left outflow, associated aortic or mitral valve insufficiency, chromosomal anomalies, arteria lusoria, and operative technique (membrane resection (22) vs associated myectomy (34) vs Konno (2)) were analyzed as risk factors for reoperation (Kaplan–Meier, Cox regression). Results: There was no operative mortality. Median follow-up spanned 2.7 years (range 0.1–10), with one late death at 4 months. Reoperation was required for recurrent stenosis in 11 patients (19%) at 2.6 years (range 0.3–7.5) after initial surgery. Risk factors for reoperation included complex subaortic stenosis (p = 0.003), younger age (p = 0.012), postoperative residual gradient (p = 0.019), and the presence of an arteria lusoria (p = 0.014). For simple lesions, no variable achieved significance for stenosis recurrence. Conclusions: Surgical relief of congenital subaortic stenosis, even with complex defects, yields excellent results. Reoperation is not infrequent, and should be anticipated with younger age at operation, complex defects, residual postoperative gradient, and an arteria lusoria. Myectomy concomitant to membrane resection, even in simple lesions, does not provide enhanced freedom from reoperation, and should be tailored to anatomic findings.     

Sympathetic stimulation increases the blood flow through the in situ right gastroepiploic artery graft after off-pump coronary artery bypass graft surgery

Objective: The right gastroepiploic artery is gaining popularity as an in situ arterial graft for coronary artery bypass surgery. Unlike the internal thoracic artery, the right gastroepiploic artery is a visceral artery and has a vasoconstrictive tendency in response to sympathetic stimulation. We hypothesized that blood flow through the in situ right gastroepiploic arterial graft might be compromised after sympathetic stimulation. Methods: Thirty patients scheduled for off-pump coronary artery bypass surgery using the left internal thoracic artery and the right gastroepiploic artery as in situ arterial grafts were enrolled. Blood flow through both arteries was measured by transit time flow before (T1), during (T2), and after noradrenalinee infusion (T3). Results: After sympathetic stimulation, blood flow of both the right gastroepiploic artery (30.1 ± 13.9 mL/min at T1 vs 36.2 ± 17.5 mL/min at T2; P = 0.001) and left internal thoracic artery grafts (37.3 ± 19.1 mL/min at T1 vs 41.8 ± 18.2 mL/min at T2; P = 0.01) was increased significantly. However, blood flow in proportion to cardiac output increased only in the right gastroepiploic artery graft (P = 0.01). Conclusions: Sympathetic stimulation increases, rather than compromises, blood flow through the right gastroepiploic artery graft after coronary revascularization.     

Improving the surgery for sigmoid achalasia: long-term results of a technical detail

Objective: Heller myotomy results for the treatment of sigmoid achalasia are worse than those achieved for fusiform achalasia. We retrospectively examined two groups of sigmoid achalasia patients, in which we performed (1) the standard Heller–Dor procedure (no pull-down) and (2) the Heller–Dor plus a technique apt to obtain the verticality of the oesophageal axis (pull-down). We verified whether the latter technique improved long-term results. Materials and methods: We considered 33 patients affected by primitive oesophageal sigmoid achalasia operated upon consecutively (1979–2005). Diagnosis was based on symptoms, manometry, radiology and endoscopy. After 1987, we routinely isolated 360° of the gastro-oesophageal junction and the lower oesophagus and applied U stitches at the right side of the lower oesophagus to pull down and rotate the gastro-oesophageal junction toward the right. Fifteen patients underwent the no pull-down and 18 patients underwent the pull-down technique. Postoperative follow-up included objective clinical and instrumental evaluation (questionnaire filled by a surgeon including the assessment of symptoms and endoscopic reflux oesophagitis according to a semi-quantitative scale) and subjective evaluation (self-evaluation SF-36 questionnaire). Results: The mean follow-up period was 89 months (range 12–261 months). The postoperative dysphagia score was significantly improved in the entire group. Excellent results were present in 12 patients (36.4%), good in 11 (33.3%), fair in 3 (9.1%) and insufficient in 7 patients (21.2%). No statistically significant differences were observed between the two groups with regard to the postoperative symptoms and oesophagitis. Postoperative radiological measurements of oesophageal diameter and residual barium column were significantly improved in the whole group and within each group with respect to the radiological variables measured preoperatively (p = 0.000). In the comparison of the two groups, statistically significant differences were observed with regard to mean oesophageal diameter (p = 0.030) (pull-down, 4 ± 0.9 cm; no pull-down, 4.7 ± 0.6 cm) and residual barium column (p = 0.048) (pull-down, 6.2 ± 3.4 cm; no pull-down, 9.6 ± 5.8 cm). Conclusions: The Heller–Dor operation is effective in the presence of sigmoid achalasia. The clinical objective and subjective evaluations show a trend toward the improvement of results with the pull-down technique. Stronger statistical significance would probably be obtained from a larger case series.     

Post-transplant diabetes mellitus in lung transplant recipients: incidence and risk factors

Objective: Post-transplant diabetes mellitus (PTDM) is a common and potentially serious complication after solid organ transplantation. There are only a few data, however, about the incidence of DM in patients undergoing lung transplantation. Patients and methods: The medical records of 119 consecutive patients who underwent lung transplantation from 1998 to September 2004 were reviewed. Patients were divided in three groups according to their diabetes status, including pre-transplant DM, the PTDM group and those without DM. Patient records and all laboratory data were reviewed and the clinical course of diabetes was monitored. All recipients were treated with tacrolimus based regimen. Results: Mean follow-up for all patients was 25 ± 10. Twenty-three patients had DM in the pre-lung transplantation (LTX) DM group. PTDM developed in 34 of the remaining 96 patients (35.4%) with an incidence of 20%, 23% after 6 months and 12 months post-transplant. No significant difference was noted between 12 and 24 months post-LTX. The patients who developed DM were older (57 ± 15 vs 53 ± 13 years, p = 0.009), had increased BMI (26 ± 5 vs 24 ± 4, p = 0.0001), shorter time from diagnosis to LTX (21 ± 13 vs 28 ± 18 months, p = 0.007) more cytomegalovirus infection and more acute rejection and hyperglycemia in the first month after LTX. Four patients died in the PTDM group compared to nine patients in the no-DM group (12% vs 14%; p = 0.72). Conclusions: Post-transplant diabetes is a common complication in lung transplant patients receiving tacrolimus-based immunosuppression. The risk for developing PTDM is greatest among older recipients, those obese, and among recipients with more rejections episodes.     

Mitral valve repair by Alfieri''s technique does not limit exercise tolerance more than Carpentier''s correction

Objective: The main goal of this study was to evaluate if the edge-to-edge mitral repair could be a limiting factor for exercise tolerance and to compare these results to those of classical techniques. Methods: Between 2000 and 2002, 54 consecutive patients were operated on for mitral valve regurgitation (MR). Twenty-five patients were operated with Alfieri's technique (group A) and 29 patients with Carpentier's technique (group C). The mean age was 63.9 years in group A and 63.8 years in group C (p = 0.98). After a mean follow-up of 16.2 ± 12 months, survivor patients were seen at the outpatient clinic, by the same physician for a clinical evaluation, an echocardiogram at rest and at peak exercise, and received a cardiorespiratory exercise testing with maximal oxygen uptake (VO₂ max) recording. Results: Clinical status improved with 0% of the patients in class NYHA III or IV in either group postoperatively versus 77% preoperatively. There was no significant MR in 80% of cases in group A versus 89.6% in group C (p = 0.54). The mean mitral valve area was 2.5 and 2.9 cm² in groups A and C, respectively (p = 0.018). The mitral gradient at rest was 3.8 and 3.3 mmHg (p = 0.31) and the mitral gradient at peak exercise was 8.5 and 9.7 mmHg (p = 0.22) in groups A and C, respectively. Cardiorespiratory exercise testing showed a mean VO₂ max of 73.7 ± 15% of normal value in group A versus 79.6 ± 13.1% in group C (p = 0.18). Conclusion: Alfieri's technique has the same efficiency on improvement of MR and clinical status than classical repair. Despite a higher restriction of mitral valve area at rest in group A, gradient and mean VO₂ max at peak exercise were similar in both groups.