Carlo Canosa

Midterm clinical and angiographic results of radial artery grafts used for myocardial revascularization.

OBJECTIVEnTo evaluate the midterm angiographic results of the use of radial artery grafts for myocardial revascularization.nnnMETHODSnThe first 68 consecutive surviving patients who received a radial artery graft proximally anastomosed to the aorta at our institution were studied again at 5 years (mean 59 +/- 6.5 months) of follow-up; 48 of these patients had previously undergone an early angiographic examination. The response of the radial artery to the endovascular infusion of serotonin was evaluated 1 and 5 years after the operation, and the midterm status of the radial artery graft was correlated with the degree of preoperative stenosis of the target vessel and with calcium-channel blocker therapy.nnnRESULTSnThe patency and perfect patency rates of the radial artery grafts 5 years after the operation were 91.9% and 87.0%, respectively. All radial artery grafts that were patent early after the operation remained patent at midterm follow-up, and early parietal irregularities in 7 patients were seen to have disappeared after 5 years. The early propensity toward graft spasm after serotonin challenge was markedly decreased at midterm follow-up. The continued use of calcium-channel antagonists after the first postoperative year did not influence the radial artery graft status, whereas the preoperative severity of the target-vessel stenosis markedly influenced the angiographic results.nnnCONCLUSIONSnThe midterm angiographic results of radial artery grafts used for myocardial revascularization are excellent. The correct surgical indication is essential. Continued therapy with calcium-channel antagonists after the first year does not influence the midterm angiographic results.

Myocardial revascularization with and without cardiopulmonary bypass: advantages, disadvantages and similarities

OBJECTIVESnOff-pump coronary artery bypass surgery is becoming increasingly popular although its effectiveness remains controversial. Our goal was to investigate the effectiveness of on-pump and off-pump coronary artery bypass surgery on early (30 days) and long-term (5 years) clinical outcome in two groups of patients selected using propensity scores.nnnMETHODSnFrom November 1994 to December 2001, 4381 patients underwent isolated coronary surgery. Applying propensity score matching, 1922 patients were selected (off-pump n=961, on-pump n=961).nnnRESULTSnStepwise logistic regression analysis showed that the use of cardiopulmonary bypass was an independent predictor for early death, cerebral vascular accident, early negative primary endpoints (ENPEP), and early major events (EME). Five years freedom from both events was similar in the two groups. However, freedom from acute myocardial infarction (AMI) in grafted areas was higher in the off-pump than in the on-pump patients, a possible explanation being the lower postoperative creatine kinase myocardial band (CKMB) release. Grouping all patients according to CKMB peak release also showed that patients with normal release values had higher freedom from all cardiac events investigated. A subgroup analysis of 59 patients converted from off-pump to on-pump showed higher early mortality, ENPEP, and EME. Conversion, however, did not affect late clinical outcome.nnnCONCLUSIONSnThese results suggest that off-pump surgery reduces early mortality and morbidity. Conversion to on-pump carries high in-hospital mortality and morbidity. Long-term clinical outcome is similar in the two groups; however, off-pump patients seemed to have a higher freedom from AMI in the grafted area which might be related to the lower CKMB peak release when compared with patients undergoing on-pump surgery.

Comparison of response to serotonin of radial artery grafts and internal mammary grafts to native coronary arteries and the effect of diltiazem.

We studied the response of radial artery (RA) or left internal mammary artery grafts to the intraluminal infusion of serotonin in 22 consecutive patients 1 year after the operation, subsequently evaluating the effect of diltiazem in 9 patients. Serotonin causes a significant vasoconstriction of the RA grafts, but not of the left internal mammary artery grafts, whereas oral diltiazem treatment does not prevent the effect of the higher dose of serotonin on RA grafts.

Human Mesenchymal Stem Cells Reendothelialize Porcine Heart Valve Scaffolds: Novel Perspectives in Heart Valve Tissue Engineering

Abstract Heart valve diseases are usually treated by surgical intervention addressed for the replacement of the damaged valve with a biosynthetic or mechanical prosthesis. Although this approach guarantees a good quality of life for patients, it is not free from drawbacks (structural deterioration, nonstructural dysfunction, and reintervention). To overcome these limitations, the heart valve tissue engineering (HVTE) is developing new strategies to synthesize novel types of valve substitutes, by identifying efficient sources of both ideal scaffolds and cells. In particular, a natural matrix, able to interact with cellular components, appears to be a suitable solution. On the other hand, the well-known Whartons jelly mesenchymal stem cells (WJ-MSCs) plasticity, regenerative abilities, and their immunomodulatory capacities make them highly promising for HVTE applications. In the present study, we investigated the possibility to use porcine valve matrix to regenerate in vitro the valve endothelium by WJ-MSCs differentiated along the endothelial lineage, paralleled with human umbilical vein endothelial cells (HUVECs), used as positive control. Here, we were able to successfully decellularize porcine heart valves, which were then recellularized with both differentiated-WJ-MSCs and HUVECs. Data demonstrated that both cell types were able to reconstitute a cellular monolayer. Cells were able to positively interact with the natural matrix and demonstrated the surface expression of typical endothelial markers. Altogether, these data suggest that the interaction between a biological scaffold and WJ-MSCs allows the regeneration of a morphologically well-structured endothelium, opening new perspectives in the field of HVTE.

Repair of an ascending aorta pseudoaneurysm by way of superior ministernotomy

A wide ascending aorta pseudoaneurysm occurring 10 years after uncomplicated aortic valve replacement was successfully repaired using a superior ministernotomy and femoral-femoral cannulation. In this setting, a limited sternal incision minimized the risk of pseudoaneurysm rupture during dissection and allowed safe isolation of the target cardiac structures.

Open Clip-Free Radial Artery Harvesting With the Harmonic Shears

Abstractu2003 Background: The Ultracision Harmonic Scalpel is associated with several advantages in radial artery (RA) harvesting. It allows fewer hemostatic clips to close the collateral branches, less thermal injury of the conduit, and reduced time of harvesting in comparison with the conventional RA harvesting technique with electrocautery and hemostatic clips. We recently started open RA harvesting with the harmonic shears (HSH). In this study, we aimed at evaluating the feasibility of this simplified ultrasonically activated harvesting technique, and report the results of RA harvesting with HSH. Methods: The RA harvesting with HSH was performed in 20 patients operated on for myocardial revascularization from July 2004 to December 2005. Results: The harvest of the RA was completed in little time, without any complication. Neither bleeding from the collateral branches nor spasm alongside the entire length of the RA was observed. No bleeding occurred from the muscles of the forearm. Conclusion: This technique of RA harvesting with HSH is impressive in terms of short time of harvest, complete absence of clips for the collateral branches, and no thermal injury of the conduit.

The “Button Inside” Technique for the Aortic Root Replacement: A Modified Button Technique

Abstractu2002 Modified button technique for reattachment of coronary arteries in the aortic root replacement is reported. Anastomosis of the coronary buttons is performed from the inside of the composite valve graft previously including the coronary buttons in the composite valve graft. Reduced tension is present between coronary arteries and the composite valve graft once the heart is beating and the systemic pressure is increasing. In this way coronary buttons are reinforced directly by the composite aortic wall graft prosthesis. The coronary ostia are perfused with lower tension at the site of the coronary anastomoses. No bleeding from the suture line of the coronary buttons occurs using this new surgical approach.