Raffaele Bonato

Incidence, Predictors, and Outcome of Conduction Disorders After Transcatheter Self-Expandable Aortic Valve Implantation

The aims of the present study were to investigate the incidence and characteristics of conduction disorders (CDs) after transcatheter aortic valve implantation (TAVI), to analyze the predictors of permanent pacemaker (PPM) implantation, and to evaluate the outcomes of CDs over time. In particular, we sought to investigate whether the depth of deployment and other technical aspects of valve implantation might predict the need for PPM implantation after TAVI. TAVI has been reported to favor the onset or worsening of CDs often requiring PPM implantation. A total of 70 patients with aortic stenosis due to dystrophic calcification underwent TAVI with third-generation CoreValve Revalving System from May 2007 to April 2009. We collected electrocardiograms at baseline, during TAVI, during hospitalization and at the 1-, 3-, 6-, and 12-month follow-up visits thereafter. The clinical, anatomic, and procedural variables were tested to identify the predictors of PPM implantation. The PPM dependency at follow-up was analyzed. Six patients were excluded from the analysis because of a pre-existing PPM. Of the 64 patients, 32 (50%) had one or more atrioventricular-intraventricular CDs at baseline. TAVI induced a worsening in the CDs in 49 (77%) of the 64 patients, with 25 (39%) requiring in-hospital PPM implantation. On multivariate analysis, the independent predictors of PPM implantation were the depth of the prosthesis implantation (p = 0.039) and the pre-existing right bundle branch block (p = 0.046). A trend in the recovery of the CDs over time was recorded, although 2 patients required PPM implantation 1 month after discharge for late complete atrioventricular block. In conclusion, TAVI often induces or worsens CDs, requiring PPM in more than one third of patients, although a trend in the recovery of CDs during the midterm was recorded. The independent predictors of PPM implantation were the depth of prosthesis implantation and pre-existing right bundle branch block.

Expanding the eligibility for transcatheter aortic valve implantation the trans-subclavian retrograde approach using: the III generation CoreValve revalving system.

OBJECTIVES Our aim was to assess the safety and feasibility of the retrograde trans-subclavian approach to transcatheter aortic valve implantation (TAVI) in selected high-risk patients with aortic stenosis (AS) and severe peripheral vasculopathy. BACKGROUND TAVI is an emerging therapeutic option to treat inoperable/high-risk patients affected by symptomatic AS. However, these patients are also often affected by severe iliac-femoral arteriopathy, rendering the transfemoral approach unemployable for percutaneous revalving procedure. METHODS From among those patients in our department between May 2007 and December 2008, who were refused surgical aortic valve replacement because of high surgical risk and were ineligible for transfemoral percutaneous aortic valve replacement, we scheduled 3 for TAVI by the subclavian approach. Procedures were performed by a combined team of cardiologists, cardiac surgeons, and anesthetists in the catheterization laboratory. The III generation CoreValve Revalving System (CoreValve Inc., Irvine, California) with an 18-F delivery system was introduced in all cases by the left subclavian artery. RESULTS Prosthetic valves were successfully implanted in all 3 cases, leading to a fall in transvalvular gradient without significant paravalvular regurgitation. No intraprocedural or periprocedural complications occurred. Two patients developed an atrioventricular block requiring the implantation of a permanent pacemaker. All patients were discharged in asymptomatic status, with good prosthesis performance. No adverse events occurred within the 3-month follow-up. CONCLUSIONS TAVI by subclavian retrograde approach seems safe and feasible in inoperable/high-risk patients with AS and peripheral vasculopathy, who are neither eligible for surgical valve replacement nor transfemoral percutaneous aortic valve implantation. Further studies are needed to evaluate the long-term efficacy of this new therapy.

Life-threatening anaphylactic shock caused by porcine heparin intravenous infusion during mitral valve repair

J Thorac Cardiovasc Surg 2003;126:1194-1195 Gerosa Tomaso Bottio, Giorgio Pittarello, Raffaele Bonato, Umberto Fagiolo and Ginoinfusion during mitral valve repair Life-threatening anaphylactic shock caused by porcine heparin intravenoushttp://jtcs.ctsnetjournals.org/cgi/content/full/126/4/1194 located on the World Wide Web at: The online version of this article, along with updated information and services, is

Surgical treatment of complete A-V canal defects in children before 3 months of age

OBJECTIVES Surgical repair of complete A-V canal defects (CAVCD) is a well established procedure which is currently performed in infancy. The aim of this study is to evaluate surgical results of correction in early infancy in comparison to older age. METHODS From January 1985 to March 2001, 119 consecutive patients (age range 27 days to 83 months, mean 6.7 months) underwent repair of CAVCD in our Institution. Forms with unbalanced ventricles in association with Fallots tetralogy or heterotaxia were excluded from this series. Fifty-eight patients (49%) underwent correction before 3 months of age (Group A), and 61 patients (51%) after 3 months (Group B). Surgical repair was accomplished with a double patch technique in 100 patients (84%). Associated surgical lesions were treated simultaneously in 48 patients (40%). RESULTS There were 11 operative deaths (<30 days) (two in Group A (3.4%) and nine in Group B (15%)) (P = 0.05). The remaining patients were discharged home in good haemodynamic condition. Reoperation for postoperative left A-V incompetence occurred in five patients in Group A and in eight patients in Group B. There were eight late deaths (three in Group A and five in Group B), of which four were non-cardiac related. At a mean follow-up time of 80 months (range 2-184 months) 100 patients are asymptomatic and well, and free from oral medication. Echocardiographic examination showed absent or mild residual left A-V valve incompetence in 91 patients (49 in Group A and 42 in Group B) and moderate left A-V valve incompetence in nine patients (four in Group A and five in Group B). Kaplan-Meier survival estimates at 10 years were 90% for Group A and 75% for Group B. Kaplan-Meier freedom from reoperation at 10 years was 89% for Group A and 84% for Group B. CONCLUSIONS Our data demonstrate that repair of CAVCD under 3 months of age is the ideal approach to this malformation with a lower mortality rate at operation compared to older patients. Logistic analysis showed that an operative age >3 months is, compared to an age < or =3 months, an incremental risk factor for hospital mortality with an odds ratio of 4.8 (95% confidence limit 1-23.5) (P = 0.05). In the long term, freedom from reoperation for left A-V valve incompetence is higher when compared to children repaired at an older age.

Value of transesophageal echocardiography during repair of congenital heart defects

Two-dimensional transesophageal color Doppler echocardiography was employed intraoperatively in 30 children undergoing repair of a variety of simple and complex cardiac malformations. There were 16 female and 14 male patients, with a mean age of 9 +/- 3 years (range, 4 to 13 years) and a mean weight of 31 +/- 9 kg (range, 16 to 50 kg), 16 children weighing less than 30 kg. A standard, commercially available transesophageal echocardiography probe (5 MHz, 64 elements) was used in all patients without complications. Transesophageal echocardiography proved helpful in selecting the surgical approach, in assessing the adequacy of surgical repair, in detecting residual intracardiac shunts, and in allowing uninterrupted monitoring of ventricular performance throughout the procedure. Our initial experience suggests that transesophageal echocardiography is a valuable tool to be used in children with congenital cardiac malformations, particularly in those requiring complex intracardiac procedures. The amount of information obtained by the surgeon should favor the routine use of transesophageal echocardiography during open heart procedures and stimulate the development of probes to be safely used even in infants and newborns.

Intraoperative plasmapheresis in cardiac surgery

OBJECTIVE To determine the effects of intraoperative plasmapheresis on total transfusion requirements, mediastinal drainage, and coagulation. DESIGN The trial was prospective, randomized, and controlled. SETTING Inpatient cardiac surgery at a university medical center. PARTICIPANTS Two hundred ninety-three consecutive patients undergoing cardiac surgery requiring cardiopulmonary bypass. INTERVENTIONS Intraoperative plasmapheresis (IP) was performed in 147 patients before heparinization; platelet-rich plasma was reinfused immediately after heparin reversal. MEASUREMENTS AND MAIN RESULTS Mediastinal chest tube drainage during the first 12 postoperative hours was significantly less in the IP group (p = 0.022), but no difference was noted in total postoperative blood loss between the two groups. The amount of packed red cells and fresh frozen plasma transfused to the IP group in the intensive care unit was significantly lower (p = 0.02, p = 0.002, respectively); 51.4% of patients required no transfusion compared with the control group (34.5%) (p = 0.006). No differences were noted for data collected in the intensive care unit in terms of the mean duration of chest tube drainage, ventilator time, or any hematologic variables at baseline or at any subsequent time in the study. CONCLUSIONS After cardiac surgery, intraoperative plasma-pheresis reduces early postoperative bleeding and decreases the need for homologous transfusions.

Propofol-fentanyl versus isoflurane-fentanyl anesthesia for coronary artery bypass grafting: Effect on myocardial contractility and peripheral hemodynamics

To avoid intraoperative awareness and postoperative respiratory depression from high-dose opioid anesthesia, propofol (P), or isoflurane (I) has been combined with moderate-dose opioid with varying results. However, the effects of both P and I on myocardial contractility and left ventricular afterload have not been completely quantified. The end-systolic pressure-diameter relationship (ESPDR) of the left ventricle (LV) is a reliable method to quantitatively assess LV contractility because it is relatively independent of changes in preload and incorporates afterload changes. The purpose of this study was to quantify the cardiodynamic effects of propofol-fentanyl (PF) anesthesia in comparison with isoflurane-fentanyl (IF) anesthesia in patients undergoing coronary artery bypass grafting (CABG). Thirty patients with normal or moderately impaired LV function (ejection fraction > or = 40% with LV end-diastolic pressure < or = 18 mmHg, no preoperative akinesia or dyskinesia) undergoing elective CABG were studied. After premedication with flunitrazepam, 2 mg orally, all patients were induced with thiopental, 1 mg/kg, fentanyl, 20 micrograms/kg, and vecuronium, 0.1 mg/kg, and were ventilated with oxygen/air (F(1)O2 0.6). Anesthesia was maintained throughout the procedure with a zero-order intravenous (IV) continuous infusion of P, 3 mg/kg/h (PF group), or with isoflurane inhalation of 0.6% (IF group), supplemented by intermittent boluses (5 micrograms/kg) of fentanyl (up to a total maintenance dose of 30 micrograms/kg). After intubation, a cross-section of the LV was visualized by two-dimensional transesophageal echocardiography and an m-mode echocardiogram was obtained at the maximum anterior-posterior diameter. The radial artery pressure tracing and the ECG were simultaneously recorded with the M mode.(ABSTRACT TRUNCATED AT 250 WORDS)

Totally percutaneous valve replacement for severe aortic regurgitation in a degenerating bioprosthesis.

Recently, the feasibility and safety of percutaneous aortic valve replacement (PAVR) has been reported in the treatment of degenerative aortic valve stenosis in patients at high-risk for surgical aortic valve replacement (AVR). However, so far this therapy has been limited to patients with severe stenosis of the native valve. We report the case of a patient with severe aortic regurgitation owing to bioprosthesis dysfunction who was successfully treated by implantation of a CoreValve (CoreValve Inc, Irvine. Calif) prosthesis with a totally percutaneous approach.

Value and limitations of transesophageal echocardiographic monitoring during percutaneous balloon mitral valvotomy

To determine the utility of transesophageal echocardiographic monitoring during percutaneous balloon mitral valvotomy, we analyzed data from 40 consecutive patients who had been randomly assigned to undergo balloon mitral valvotomy under transesophageal echocardiographic guidance or without echo. All procedures were carried out under general anaesthesia. The completion rate (100% vs 73%), the procedure time (108 +/- 28 min vs 65 +/- 18 min), the X-ray exposure time (62 +/- 13 vs 33 +/- 12 min), resulted significantly (P less than 0.001) more favorable in the echo-monitored patients. Moreover, a lower rate of major complications (cardiac tamponade, large residual atrial shunting, and severe mitral regurgitation) was noted in the echo-monitored patients. The achieved final area of the mitral valve did not differ significantly between the two groups. From an evaluation of results as a whole, 96% of the echo-monitored procedures were successful, whereas only 40% of the procedures conducted without echocardiographic control achieved a satisfactory final result in absence of major complications. We conclude that transesophageal echocardiography is a safe, effective, and valuable tool to monitor each step of balloon mitral valvotomy in order to shorten the time of the procedure, and to improve the results of this complex interventional catheterization technique.

Four-side near-infrared spectroscopy measured in a paediatric population during surgery for congenital heart disease.

In this study we monitored renal, hepatic and muscular oxygen saturations by near-infrared spectroscopy and we evaluated the correlation with variables that could affect tissue oxygenation in 16 paediatric patients during surgical heart procedure. We considered the following phases: 1) basal time (after induction of anaesthesia and before median sternotomy), 2) before starting cardiopulmonary bypass, 3) 15 min after starting it, 4) at half time, 5) 15 min before the end, 6) at the end, 7) 15 min after the end, and 8) 10 min before paediatric intensive care unit admission. Heart rate, mean arterial pressure, peripheral oxygen saturation, serum lactate, haemoglobin, blood gas analysis, and rectal temperature were registered. We found a decrease of all monitored regional saturations (rSO(2)) (cerebral P = 0.006, hepatic P = 0.005) before starting the bypass. After this time, cerebral saturation gradually increased without reaching the basal value; renal and liver saturations increased after starting bypass; muscular rSO(2) increased in the second half (P = 0.005). A statistically significative inverse correlation between cerebral rSO(2) and pH was observed. In conclusion, during paediatric heart surgery a vulnerable period was identified. We underline the necessity to monitor this phase.