Reza Tavakoli

Gene regulatory control of myocardial energy metabolism predicts postoperative cardiac function in patients undergoing off-pump coronary artery bypass graft surgery : Inhalational versus intravenous anesthetics

Background: Anesthetic gases modulate gene expression and provide organ protection. This study aimed at identifying myocardial transcriptional phenotypes to predict cardiovascular biomarkers and function in patients undergoing off-pump coronary artery bypass graft surgery. Methods: In a prospective randomized trial, patients undergoing elective off-pump coronary artery bypass graft surgery were allocated to receive either the anesthetic gas sevoflurane (n = 10) or the intravenous anesthetic propofol (n = 10). Blood samples were collected perioperatively to determine cardiac troponin T, N-terminal pro-brain natriuretic peptide, and pregnancy-associated plasma protein A. Cardiac function was measured with transesophageal echocardiography and pulmonary artery thermodilution. Atrial biopsies were collected at the beginning and end of bypass surgery to determine gene expression profiles. Results: N-terminal pro-brain natriuretic peptide and pregnancy-associated plasma protein A blood levels were decreased with sevoflurane treatment. Echocardiography showed preserved postoperative cardiac function in sevoflurane patients, which paralleled higher cardiac index measurements. N-terminal pro-brain natriuretic peptide release was predicted by sevoflurane-induced transcriptional reduction in fatty acid oxidation, whereas changes in cardiac index were predicted by preoperative gene activity of the peroxisome proliferator-activated receptor &ggr; coactivator-1&agr; pathway. Sevoflurane-mediated attenuation of transcripts involved in DNA-damage signaling and activation of the granulocyte colony-stimulating factor survival pathway predicted improved postoperative cardiac index and diastolic heart function, respectively. Conclusions: Anesthetic-induced and constitutive gene regulatory control of myocardial substrate metabolism predicts postoperative cardiac function in patients undergoing off-pump coronary artery bypass graft surgery. The authors analysis further points to novel cardiac survival pathways as potential therapeutic targets in perioperative cardioprotection.

Results of surgery for irreversible moderate to severe mitral valve regurgitation secondary to myocardial infarction

OBJECTIVEnModerate to severe irreversible mitral regurgitation secondary to myocardial infarction is an independent risk factor for reduced long-term survival. Late effects of correction of mitral incompetence concomitant with coronary artery bypass grafting (CABG) are less well known and the choice of mitral valve procedure is still debated.nnnMETHODSnFrom 1988 to 1998, 93 consecutive patients (mean age 63+/-9 years) were treated for moderate to severe irreversible mitral regurgitation secondary to myocardial infarction; 84 were in NYHA functional class III-IV and 19 were in cardiogenic shock. Thirty-seven patients underwent emergency surgery. Perioperative intraaortic balloon pump (IABP) was necessary in 33 patients. Follow-up ranged from 6 months to 12 years (mean 51 months+/-41).nnnRESULTSnMitral valve was repaired in 30 patients and replaced in 63. Replacement was preferably performed in patients with major displacement of papillary muscle and in patients with acute papillary muscle rupture. CABG (3.4 distal anastomoses) was performed in all patients and was complete in 92%. Early mortality was 15% (14/93). Multivariable analysis identified need for IABP (P=0.005) and COPD (P=0.02) as risk factors for early death. Emergency surgery had only a trend (P=0.15) for increased mortality; age, low ejection fraction, repair vs. replacement had no influence. Actuarial survival rates at 1, 5 and 10 years were 81, 65 and 56%, respectively. Late survival was similar in patients with replacement or repair (P=0.46). At last follow-up, all but one patient were in NYHA functional class I or II.nnnCONCLUSIONSnCombined mitral valve procedure and myocardial revascularization, as complete as possible, for moderate to severe mitral regurgitation secondary to myocardial infarction achieve satisfactory early and late outcome despite the increased operative mortality. Acute papillary muscle rupture, severe restriction of the mitral valve by major displacement of the papillary muscle are better managed by valve replacement.

Repair of postinfarction dyskinetic LV aneurysm with either linear or patch technique

OBJECTIVESnControversy still exists regarding the optimal surgical technique for postinfarction dyskinetic left ventricular aneurysm (LVA) repair. We compared the efficacy of two established techniques, linear vs. patch remodeling, for repair of dyskinetic LVA.nnnPATIENTS AND METHODSnFrom 1989 to 1998, 95 (16 women, 79 men) consecutive patients were operated on for postinfarction dyskinetic LVA. Thirty-four patients underwent patch remodeling (R) and 61 linear (L) repair. The mean age was 61.1+/-8.5 years. Indications for surgery alone or in combination included angina in 72 patients, dyspnea in 64 and ventricular tachycardia in 41. Thirty-seven patients had a history of congestive heart failure (R 13 (38%), L 24 (39%), NS). The mean ejection fraction (EF) with aneurysm was 0.29+/-0.09 in R vs. 0.35+/-0.10 in L (P<0.04), whereas the mean EF without aneurysm was 0.43+/-0.11 in R vs. 0.46+/-0.08 in L (P=0.3). Seventy-one aneurysms were anterior (R 30 (88%), L 41 (68%), P<0.05). Concomitant coronary artery bypass grafting was performed in 84 patients (R 29 (85%), L 55 (90%), NS). Follow-up ranged from 1 to 12 years (mean 5.6+/-3.4 years, median 6.1 years).nnnRESULTSnEarly mortality was 8% (n=8) (R 4, L 4, NS). Survival at 1, 5 and 10 years was 88, 73, and 44%, respectively. It did not differ significantly between R (1 and 5 year survival 85, 66%) and L (90, 76%, P=0.58). Preoperative risk factors for mortality were history of congestive heart failure (1 and 5 year survival 81 and 57% vs. 90 and 78%, respectively, hazard ratio (HR)=1.95, P<0.05), non-anterior localization of the aneurysm (86 and 49% vs. 86 and 77%, HR=2.06, P<0.05), history of thromboembolic events (57 and 19% vs. 89 and 74%, HR=3.27, P<0.05), and left ventricular EF (HR=0.97 per %, P=0.05). At late follow-up the mean functional class was 1.8+/-0.6 in long-term survivors (preoperative 2.9+/-0.9, P<0.001) with no difference between the groups.nnnCONCLUSIONSnThe technique of repair of postinfarction dyskinetic LVA should be adapted in each patient to the cavity size and extent of the scarring process into the septum and subvalvular mitral apparatus. Applying these considerations to the choice of the technique of repair, both techniques achieved satisfactory results with respect to perioperative mortality, late functional status and survival.

Clopidogrel before urgent coronary artery bypass graft

Comment Development of new operative procedures has caused a resurgence in the surgical treatment of atrial fibrillation. Like the Cox maze procedure, these new operations generally include isolation of the pulmonary veins and excision of the left atrial appendage. Exposure of these structures, particularly in a large left atrium, is challenging. A series of new atrial retractor blades (Kapp Surgical Inc, Cleveland, Ohio) provides exposure of the posterior left atrium and pulmonary vein orifices. These blades, which are malleable and universally adjustable, attach to a standard mitral valve retractor. This system provides excellent and consistent exposure of the posterior left atrium and pulmonary veins without the need for surgical assistance, facilitating operations for atrial fibrillation.

Electroporation-mediated interleukin-10 overexpression in skeletal muscle reduces acute rejection in rat cardiac allografts

Human interleukin 10 (hIL‐10) may reduce acute rejection after organ transplantation. Our previous data shows that electroporation‐mediated transfer of plasmid DNA to peripheral muscle enhances gene transduction dramatically. This study was designed to investigate the effect of electroporation‐mediated overexpression of hIL‐10 on acute rejection of cardiac allografts in the rat.

Retracted: right anterior minithoracotomy for minimal access aortic valve replacement.

Background: Controversy surrounds the safety of the use of minimal access aortic valve replacement (AVR). Most studies report on partial sternotomy as the preferred approach. Here we report our experience with a homogenous series of patients undergoing AVR through a right minithoracotomy (MAVR). Methods: Preoperative 64-multislice computer-tomography (64-MSCT) was done to optimize the approach in MAVR patients. One hundred and sixteen patients underwent MAVR by a standardized technique. Results: Guided by 64-MSCT, the second intercostal space was entered in 16 and the third in 100 patients. Anatomical contraindications to this technique were further defined by 64-MSCT: distance from intercostal space to aortic valve ≥12 cm and to aortic cannulation site ≥10 cm, aortic annulus diameter ≤19 mm, distance of the aortic valve annulus to the right coronary ostium ≤12 mm, and to the left coronary ostium ≤8 mm. Despite the prolonged operative, cardiopulmonary bypass and cross-clamp times, early mortality, and morbidity (perioperative myocardial infarction, stroke, reexploration for bleeding) in our patients compared favorably with those reports comparing minimal access and sternotomy approaches. Similarly, patient outcomes (mechanical ventilation time, intensive care stay, transfusion requirements, incidences of new-onset atrial fibrillation and deep wound infection, and need for major pain medication) consistently compared to the results reported by a meta-analysis of reports comparing minimal access and sternotomy techniques. Conclusions: Right anterior minithoracotomy is safe for isolated aortic valve replacement. Preoperative 64MSCT allows a better planning and definition of contraindications to this approach. This is a valuable technique in selected patients for isolated aortic valve replacement. doi: 10.1111/j.1540-8191.2009.00862.x (J Card Surg ****;**:**-**) In view of the growing risk profile of cardiac surgical patients, operative techniques aimed at reduction of the operative burden could potentially help in maintaining the good results obtained with standard approaches. For patients undergoing isolated myocardial revascularization, off-pump coronary artery bypass grafting is a technical option to achieve this goal.1 For patients needing valve procedures, in particular Address for correspondence: Reza Tavakoli, M.D., Ph.D., Department of Cardiac Surgery, Canton Hospital Lucerne, 6000 Lucerne 16, Switzerland. Fax: +41-41-205 45 63; e-mail: reza.tavakoli@ksl.ch aortic valve replacement (AVR), minimal access aortic valve replacement (MAVR) has been developed in order to lower surgical trauma and hence to maintain excellent results obtained through median sternotomy approach.2,3 Since its introduction, MAVR has been adopted by many centers as an alternative to conventional surgery.4 However, almost all these centers perform the MAVR through a ministernotomy or a right parasternal approach.4 Here, we report our experience in a group of patients undergoing AVR with a standardized right minithorcotomy approach5 guided by preoperative 64-multislice computer tomography (64-MSCT). RE TR AC TE D ii WEBER, ET AL. MINITHORACOTOMY AORTIC VALVE REPLACEMENT J CARD SURG ****;**:**-** TABLE 1 Exclusion Criteria for MAVR Chest deformities Previous right hemithorax surgery or irradiation Combined valve and bypass surgery Aneurysm of the ascending aorta METHODS AND PATIENTS All patients underwent routine preoperative assessment including complete blood analysis, electrocardiogram, chest X-ray, lung function test, echocardiography, and coronary angiography for patients older than 45 years. Moreover, a 64-MSCT was performed in preparation for MAVR in patients eligible (Table 1) for this procedure.