Massimo Bonacchi

Does ministernotomy improve postoperative outcome in aortic valve operation? A prospective randomized study

BACKGROUND The aim of this study was to compare the postoperative outcome obtained in patients undergoing elective aortic valve operation, either through ministernotomy or conventional sternotomy. METHODS Between January 1999 and July 2001, 80 consecutive patients undergoing elective aortic valve replacement were randomly divided into two groups: group I (n = 40 patients) undergoing a ministernotomy approach (reversed-C or reversed-L), and group II (n = 40 patients) undergoing conventional sternotomy. RESULTS The length of skin incision was significantly shorter in group I than in group II (8.2+/-1.3 cm versus 23.7+/-2.6 cm, p < 0.001). No significant differences were found in cardiopulmonary bypass duration, associated procedures, or aortic cross-clamping times. Total operating time was 3.7+/-0.46 hours in group I compared with 3.4+/-0.6 hours in group II (p = 0.014). A similar incidence of cardiac, neurologic, infective, and renal complications between groups was found. Mean mediastinal drainage and mean blood transfusions (amount of blood transfused) per patient were greater in group II (p < 0.004 and p < 0.001, respectively). Twenty-five (62.5%) patients in group II and 15 (37.5%) patients in group I required postoperative blood transfusion (p = 0.04). Mechanical ventilation time was significantly longer in group II (6.2+/-1.8 hours versus 4.4+/-0.9 hours, p = 0.006). Five days after the surgical procedure, spirometric data analysis demonstrated a significantly lower total lung capacity and maximum inspiratory and expiratory pressures in group II compared with group I (p = 0.003, p = 0.007, and p < 0.001, respectively). CONCLUSIONS Our results showed that ministernotomy had not only important cosmetic advantages but also beneficial effects in blood loss and transfusion, postoperative pain, and probably in sternal stability. Ministernotomy also improved recovery of respiratory function and allowed earlier extubation and hospital discharge.

Respiratory dysfunction after coronary artery bypass grafting employing bilateral internal mammary arteries: the influence of intact pleura

OBJECTIVE To evaluate the role of intact pleurae regarding the postoperative respiratory functional status in patients undergoing coronary revascularization employing both internal mammary arteries (IMAs), according to the pedunculated or skeletonized technique (SKT) with opened or intact pleurae. MATERIALS AND METHODS Using both IMAs, 299 patients underwent elective coronary revascularization. They were randomized and divided into group I (n=82, undergoing IMA harvesting according to the SKT without opening the pleurae); group II (n=186, undergoing IMA harvesting according the pedunculated technique with open pleurae); and group III (n=31, undergoing IMA harvesting according the SKT with incidentally opened pleurae). There were no differences regarding the preoperative patient characteristics and the anaesthetic and surgical management. RESULTS There were two deaths in group I versus seven in group II and one in group III (P=ns). The number of total arterial myocardial revascularization and arterial composite grafts was significantly higher in groups I and III than in group II, (P<0.001 and P<0.005, respectively). The incidence of postoperative complications was similar between groups. Blood loss of >1000 ml was significantly higher in group II than group I (P<0.028); but the incidence of re-thoracotomy and blood transfusion was similar between groups. The mechanical ventilation time was significantly higher in groups II and III versus group I (P<0.018 and P<0.02, respectively). The incidence of prolonged ventilation (>24 h), pleural effusion, thoracocentesis and atelectasis, resulted in being significantly higher in group II than group I. The incidence of thoracocentesis was significantly higher in group III than group I. The pain score and analgesic requirements at 1-12 h after awakening were significantly higher in groups II and III versus group I, becoming similar after the chest tubes were removed. PaO(2) was significantly higher, and PaCO(2) and FiO(2) were significantly lower in group I than groups II and III at 1 and 4 h before extubation and at 1 and 4 h after extubation. PaO(2) and PaCO(2) became similar between groups at the 5th postoperative day. CONCLUSIONS According to our results, we may conclude that pleural integrity has beneficial effects on the respiratory functional status after coronary revascularization using both IMAs. A meticulous and more careful IMA harvesting approach significantly reduces the postoperative morbidity regarding the pulmonary functional status, and as a consequence, reduces the hospital costs.

Repair of congenital malformations of the mitral valve: early and midterm results.

BACKGROUND The aims of this study were to determine early and midterm survival and freedom from reoperation, and to identify the predictors for poor postoperative outcome in children undergoing mitral valve (MV) repair owing to congenital malformations of the mitral valve. METHODS Between January 1990 and February 2001, 94 consecutive children with congenital MV disease underwent valve repair. The mean age was 5.2+/-3.3 years (range 20 days to 15 years). Twenty-five (26.6%) children were less than 1 year old. Isolated MV disease was found in 21 (22.4%) patients. MV stenosis was the predominant lesion in 21 (22.4%) patients with a mean left atrial to left ventricle diastolic peak gradient of 24.5+/-9.2 mm Hg. MV regurgitation was the predominant pathophysiology in 73 (77.6%) patients with a mean regurgitation grade of 3.3+/-0.7. RESULTS The hospital mortality was 8.5% (8 of 94). Three patients required permanent pacemaker implantation owing to complete atrioventricular block. Two patients underwent mediastinal exploration for significant bleeding. Postoperatively the echocardiography color Doppler study demonstrated a significantly lower mean end diastolic left atrium to left ventricle gradient 8.7+/-2.2 mm Hg (p < 0.001) in patients with MV stenosis and a mean regurgitation grade of 0.9+/-0.6 (p < 0.001) in patients with MV regurgitation. Actuarial survival and actuarial reoperation-free survival were 89.2% and 76.3%, respectively. Multivariate analysis demonstrated that age less than 1 year (p = 0.035), hammock MV (p = 0.0093), cardiothoracic ratio greater than 0.6 (p < 0.0001), and associated cardiac anomalies (p = 0.003) were strong predictors for poor overall freedom from reoperation and midterm survival. CONCLUSIONS Mitral valve repair for congenital mitral valve disease yields acceptable early and midterm mortality and reoperation rates. Strong predictors for poor overall freedom from reoperation and midterm survival were age less than 1 year, hammock MV, cardiothoracic ratio greater than 0.6, and associated cardiac anomalies.

Should Mild‐to‐Moderate and Moderate Ischemic Mitral Regurgitation Be Corrected in Patients with Impaired Left Ventricular Function Undergoing Simultaneous Coronary Revascularization?

Introduction: Mitral valve regurgitation (MR) occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction predicts poor outcome. This study assessed the feasibility of mitral valve (MV) surgery concomitant with coronary artery bypass grafting (CABG) in patients with mild‐to‐moderate and moderate ischemic MR and impaired LV function. Materials and Method: From January 1996 to July 2000, 49 patients (group 1) and 50 patients (group 2) with grade II and grade III ischemic MR and LV ejection fraction (EF) between 17% and 30% underwent combined MV surgery and CABG (group 1) or isolated CABG (group 2). LVEF (%), LV end‐diastolic diameter (EDD) (mm), LV end‐diastolic pressure (EDP) (mmHg), and LV end‐systolic diameter (ESD) (mm) were 27.5 ± 5, 67.7 ± 7, 27.7 ± 4, and 51.4 ± 7, respectively in group 1 versus 27.8 ± 4, 67.5 ± 6, 27.5 ± 5, and 51.2 ± 6, respectively in group 2. Groups 1 and 2 were divided into Groups 1A and 2A with mild‐to‐moderate MR (22 [45%] and 28 [56%] patients, respectively) and groups 1B and 2B with moderate MR (27 [55%] and 22 [46%], respectively). In group 1, MV repair was performed in 43 (88%) patients and MV replacement in 6 (12%) patients. Results: Preoperative data analysis did not reveal any difference between groups. Five (10%) patients in group 1 died versus 6 (12%) in group 2 (p = ns). Within 6 months after surgery, LV function and its geometry improved significantly in group 1 versus group 2 (LVEF, p < 0.001; LVEDD, p = 0.002; LVESD, p = 0.003; and LVEDP (p < 0.001) improved significantly in group 1 instead of a mild improvement in Group 2). The regurgitation fraction decreased significantly in group 1 patients after surgery (p < 0.001). There was an inverse strong correlation between postoperative forward cardiac output and regurgitation fraction (p < 0.001). LVEF and LVESD improved significantly in group versus group 2 patients (p = 0.04 and p = 0.02, respectively). The cardiac index increased significantly in group 1 and 2 (p < 0.001 and p = 0.03, respectively). LV function and geometry improved significantly postoperatively in group 1B versus group 2B (LVEDD, p = 0.027; LVESD, p = 0.014; LVEDP, p = 0.034; and LVEF, p = 0.02), instead of a mild improvement in group 1A versus group 2A (LVESD, p = 0.015; LVEF, p = 0.046; and LVEDD and LVEDP, p = 0.05). At follow‐up, 4 (67%) of 6 patients undergoing MV replacement died versus 5 (11.59/0) of patients undergoing MV repair in group 1 (p = 0.007). The overall survival at 3 years in Group 2 was significantly lower than group 1 (p < 0.009). Conclusion: MV repair and replace‐ ment‐preserving subvalvular apparatus in patients with impaired LV function offered acceptable outcomes in terms of morbidity and survival. Surgical correction of mild‐to‐moderate and moderate MR in patients with impaired LV function should be taken into consideration since yields better survival and improved LV function.

Ventilatory and ECMO treatment of H1N1-induced severe respiratory failure: results of an Italian referral ECMO center.

BackgroundSince the first outbreak of a respiratory illness caused by H1N1 virus in Mexico, several reports have described the need of intensive care or extracorporeal membrane oxygenation (ECMO) assistance in young and often healthy patients. Here we describe our experience in H1N1-induced ARDS using both ventilation strategy and ECMO assistance.MethodsFollowing Italian Ministry of Health instructions, an Emergency Service was established at the Careggi Teaching Hospital (Florence, Italy) for the novel pandemic influenza. From Sept 09 to Jan 10, all patients admitted to our Intensive Care Unit (ICU) of the Emergency Department with ARDS due to H1N1 infection were studied. All ECMO treatments were veno-venous. H1N1 infection was confirmed by PCR assayed on pharyngeal swab, subglottic aspiration and bronchoalveolar lavage. Lung pathology was evaluated daily by lung ultrasound (LUS) examination.ResultsA total of 12 patients were studied: 7 underwent ECMO treatment, and 5 responded to protective mechanical ventilation. Two patients had co-infection by Legionella Pneumophila. One woman was pregnant. In our series, PCR from bronchoalveolar lavage had a 100% sensitivity compared to 75% from pharyngeal swab samples. The routine use of LUS limited the number of chest X-ray examinations and decreased transportation to radiology for CT-scan, increasing patient safety and avoiding the transitory disconnection from ventilator. No major complications occurred during ECMO treatments. In three cases, bleeding from vascular access sites due to heparin infusion required blood transfusions. Overall mortality rate was 8.3%.ConclusionsIn our experience, early ECMO assistance resulted safe and feasible, considering the life threatening condition, in H1N1-induced ARDS. Lung ultrasound is an effective mean for daily assessment of ARDS patients.

Anomalous Origin of the Right Pulmonary Artery from the Ascending Aorta

Abstract  Objectives: The aim was to review our experience with the surgical repair of the anomalous origin of the right pulmonary artery (AORPA) from the aorta. Materials and Method: Between January 1991 and March 2001, five patients with AORPA underwent surgical correction. One patient presented isolated AOPA from the aorta. Implantation of the anomalous PA to the main PA trunk was performed by (1) direct anatomosis employing an autologous pericardial patch in two patients; (2) using an aortic flap in two patients with AORPA; and (3) using an aortic and pulmonary flaps in another patient. The mean follow‐up time was 27 months. Results: One patient died due to progressive heart failure unresponsive to inotropic support. Early postoperative pulmonary hypertension crisis was identified in patient 4, that was managed by intravenous prostacyclin. The same patient necessitated mechanical ventilation for 11 days. The mean residual gradient for all survivors was 9.5 ± 4 mmHg. The postoperative Tc‐99 m scintigraphy demonstrated 72 ± 4.5(%) lung perfusion. At follow‐up the survival was 100%. None of the followed patients required reoperation. Conclusion: The AORPA from the aorta is a rare but important entity, necessitating a scrupulous preoperative and intraoperative evaluation. The techniques employing autologous tissues for enlarging and lengthening the AORPA seem to be associated with better results in terms of postoperative restenosis. (J Card Surg 2004;19:103‐112)

Early and long-term outcome in patients undergoing aortic root replacement with composite graft according to the Bentall's technique

OBJECTIVE The aims of this study were: (i) to evaluate the early and long-term outcome in patients undergoing aortic root replacement (ARR) with a composite graft; (ii) to identify the predictors for poor overall survival in this pool of patients. MATERIAL AND METHODS Between January 1989 and December 2000, 212 patients underwent ARR with a CG. Mean age was 56+/-14 years, ranging from 16 to 77. Annuloaortic ectasia was the most frequent cause of aortic disease in this series, 81 (38%) patients, followed by atherosclerotic aneurysm 57 (27%) and type A acute aortic dissection 52 (24.5%). Marfans syndrome was present in 37 (17.5%) patients. Duration of follow-up ranged from 1 to 120 months, mean 59+/-35 months. RESULTS The overall hospital mortality was 16 (7.5%) patients. Eight of them had aortic dissection and four Marfan syndrome. The most frequently found complication resulted to be renal failure in 22 (10%) patients and low cardiac output in 15 (7%) patients. The incidence of perioperative myocardial infarction, neurological complications, respiratory complications, renal failure and coagulopathy incidence were significantly higher in patients with cardiopulmonary bypass (CPB) time >170 min, CA >40 min, and total aortic arch replacement. The actuarial survival at 1, 3 and 5 years resulted to be 91.8, 86 and 81.5%, instead the actuarial survival without re-operation resulted to be 89, 82 and 78%. The actuarial survival in patients with aortic dissection was significantly lower versus non-dissection (P=0.022). The multivariate analysis revealed the aortic dissection (P=0.03), age >65 years (P=0.014), associated coronary artery disease (P=0.002), NYHA functional class>/=3 (P=0.027), LVEF <35% (P=0.002) and total arch reconstruction (P=0.003) as strong predictors for poor overall survival in patients undergoing ARR. CONCLUSIONS The ARR with a CG offers acceptable early and long-term outcome. The predictors for poor overall survival in patients undergoing ARR seems to be preoperative aortic dissection extended into the aortic arch, older age, depressed left ventricular function and associated coronary artery disease.

Functional and histopathological improvement of the post-infarcted rat heart upon myoblast cell grafting and relaxin therapy

Although the myocardium contains progenitor cells potentially capable of regenerating tissue upon lethal ischaemic injury, their actual role in post‐infarction heart healing is negligible. Therefore, transplantation of extra‐cardiac stem cells is a promising therapeutic approach for post‐infarction heart dysfunction. Paracrine cardiotropic factors released by the grafted cells, such as the cardiotropic hormone relaxin (RLX), may beneficially influence remodelling of recipient hearts. The current study was designed to address whether grafting of mouse C2C12 myoblasts, genetically engineered to express green fluorescent protein (C2C12/GFP) or GFP and RLX (C2C12/RLX), are capable of improving long‐term heart remodelling in a rat model of surgically induced chronic myocardial infarction. One month after myocardial infarction, rats were treated with either culture medium (controls), or C2C12/GFP cells, or C2C12/RLX cells plus exogenous RLX, or exogenous RLX alone. The therapeutic effects were monitored for 2 further months. Cell transplantation and exogenous RLX improved the main echocardiographic parameters of cardiac function, increased myocardial viability (assessed by positron emission tomography), decreased cardiac sclerosis and myocardial cell apoptosis and increased microvascular density in the post‐infarction scar tissue. These effects were maximal upon treatment with C2C12/RLX plus exogenous RLX. These functional and histopathological findings provide further experimental evidence that myoblast cell grafting can improve myocardial performance and survival during post‐infarction heart remodelling and dysfunction. Further, this study provides a proof‐of‐principle to the novel concept that genetically engineered grafted cells can be effectively employed as cell‐based vehicles for the local delivery of therapeutic cardiotropic substances, such as RLX, capable of improving adverse heart remodelling.

Postoperative outcome in patients with anomalous origin of one pulmonary artery branch from the aorta

OBJECTIVES The aim was to review our experience with the surgical repair of the anomalous origin of one pulmonary branch from the aorta (AOPA). MATERIALS AND METHOD Between January 1991 and March 2002, eight patients with AOPA underwent surgical correction. Three patients presented isolated AOPA. Five patients presented right AOPA and three, left AOPA. Implantation of the AOPA to the main pulmonary artery was performed by: (I) direct anastomosis in two patients with left AOPA; (II) interposition of a synthetic graft in one patient with left AOPA; (III) employing an autologous pericardial patch in two patients with right AOPA; (IV) using an aortic flap in three other patients with right AOPA. The mean follow-up time was 37.7 months. RESULTS One patient died postoperatively due to progressive heart failure unresponsive to inotropic support. Early postoperative pulmonary hypertension crisis was identified in another patient. Within 1 year after surgery, the mean residual gradient across the anastomotic site at follow-up was 14+/-8 mmHg. The patient undergoing interposition of a synthetic graft presented a residual gradient of 29 mmHg and underwent reoperation at almost 2.5 years after the first correction. The residual gradient in patients undergoing correction according to technique I was 17+/-3 mmHg, and in patients undergoing implantation of the AOPA according to techniques III or IV was 9.5+/-4.6 mmHg (P=0.11). Similarly, the Tc-99m scintigraphy demonstrated that a lower lung perfusion (the lung perfused from the respective AOPA compared with the contralateral lung) in patients undergoing AOPA implantation according to technique I was 59+/-6(%) and in patients undergoing techniques III or IV was 72+/-4.5(%) (P=0.038). At follow-up, all patients were alive. CONCLUSION The AOPA from the aorta is a rare but important entity, necessitating a scrupulous preoperative and intraoperative evaluation. Patients presenting this anomaly may undergo correction using various surgical techniques with acceptable results. The techniques employing autologous tissues for enlarging and lengthening the AOPA seems to be associated with less restenosis at the anastomotic site, however, larger series of patients are required to confirm such outcome.

A novel strategy to improve systemic oxygenation in venovenous extracorporeal membrane oxygenation: The “χ-configuration”

BACKGROUND Venovenous extracorporeal membrane oxygenation (VV-ECMO) is used in refractory acute respiratory distress syndrome where lung recovery is the primary goal. For its achievement, adequate extracorporeal blood flow and a maximal separation between oxygenated (inflow) and deoxygenated (outflow) blood flow are essential for reducing the recirculation phenomenon. We introduce the χ-configuration, a new cannulation strategy for VV-ECMO. PATIENTS AND METHODS We report our experience with 30 VV-ECMO consecutive patients: in 16 patients (group NS) we applied the χ-configuration, which consists of a particular right atrial cannula arrangement and a self-made modified inflow cannula, consisting of an outflow multihole venous cannula that was inserted percutaneously through the right femoral vein, into the right atrium, just below on the superior vena cava, and a self-made modified curved inflow cannula (inserted percutaneously through the right internal jugular vein) that, in its terminal segment, permitted the tip to be positioned close to the tricuspid valve. In 14 patients (group C) we applied the standard femoro-jugular VV-ECMO 2-cannula setting. In both groups, efficacy of blood oxygenation was obtained by gas-blood analysis, by blood samples obtained at arterial, central venous, and pulmonary artery lines, and by ECMO inflow and outflow lines. The recirculation fraction was obtained by a specific bedside formula. RESULTS No differences were noted between groups regarding the pre-ECMO patient characteristics. No complications during cannulation were recorded. In group NS, on-ECMO time, post-ECMO mechanical ventilation time, and ECMO overall results were significantly better than in group C. During high-flow VV-ECMO, pulmonary and systemic arterial oxygen saturation and arterial oxygen tension were significantly higher in group NS, and blood recirculation fraction was significantly lower. CONCLUSIONS Our data indicate that χ-configuration can be safe, feasible, and more effective than conventional VV-ECMO. It permits near complete drainage of the desaturated blood and a preferential oxygenated blood inflow toward the tricuspid valve, resulting in a significant reduction of recirculation, thereby improving the patients oxygenation. Our innovative strategy reduces on-ECMO and post-ECMO mechanical ventilation time, gives a faster and better pulmonary recovery, improves survival, and can reduce hospital costs.