Francesco Alessandrini

Long-Term Results of the Radial Artery Used for Myocardial Revascularization

Background—No information is available on the long-term results of radial artery (RA) grafts used as coronary artery bypass conduits. Methods and Results—In this report, we describe the long-term (105±9 months) angiographic results of a series of 90 consecutive patients in whom the RA was used as a coronary artery bypass conduit directly anastomosed to the ascending aorta. The long-term patency and perfect patency rates of the RA were 91.6% and 88%, respectively, versus 97.5% and 96.3% for internal thoracic artery grafts. The severity of stenosis of the target vessel clearly influenced long-term RA patency, whereas location of the target vessel and long-term use of calcium channel blockers did not influence angiographic results. Preserved endothelial function and absence of flow-limiting, fibrous, intimal hyperplasia were also documented. Conclusions—Ten years after surgery, RA grafts have excellent patency and perfect patency rates. Appropriate surgical technique and correct indication are the key factors for long-term RA patency.

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

OBJECTIVE To evaluate the midterm angiographic results of the use of radial artery grafts for myocardial revascularization. METHODS The 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. RESULTS The 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. CONCLUSIONS The 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.

Topical use of tranexamic acid in coronary artery bypass operations: A double-blind, prospective, randomized, placebo-controlled study

OBJECTIVES We sought to investigate the effect of topical application of tranexamic acid into the pericardial cavity in reducing postoperative blood loss in coronary artery surgery. METHODS A prospective, randomized, double-blind investigation with parallel groups was performed. Forty consecutive patients undergoing primary coronary surgery were randomly assigned to group 1 (tranexamic acid group) or group 2 (placebo group). Tranexamic acid (1 g in 100 mL of saline solution) or placebo was poured into the pericardial cavity and over the mediastinal tissues before sternal closure. The drainage of mediastinal blood was measured hourly. RESULTS Chest tube drainage in the first 24 hours was 485 +/- 166 mL in the tranexamic acid group and 641 +/- 184 mL in the placebo group (P =.01). Total postoperative blood loss was 573 +/- 164 mL and 739 +/- 228 mL, respectively (P =.01). The use of banked donor blood products was not significantly different between the two groups. Tranexamic acid could not be detected in any of the blood samples blindly collected from 24 patients to verify whether any systemic absorption of the drug occurred. There were no deaths in either group. None of the patients required reoperation for bleeding. CONCLUSIONS Topical application of tranexamic acid into the pericardial cavity after cardiopulmonary bypass in patients undergoing primary coronary bypass operations significantly reduces postoperative bleeding. Further studies must be carried out to clarify whether a more pronounced effect on both bleeding and blood products requirement might be seen in procedures with a higher risk of bleeding.

Prospective, Randomized Clinical Trial of the FloSeal Matrix Sealant in Cardiac Surgery

BACKGROUND Topical hemostatic agents composed of a gelatin-based matrix and thrombin have been reported to be effective, in addition to traditional means, in terminating bleeding during cardiac operations. We compared a hemostatic matrix sealant agent (FloSeal; Baxter Inc, Deerfield, IL) with alternative topical hemostatic agents in a mixed cohort of elective cardiac and thoracic aortic operations. METHODS Following sample size calculation, in a prospective randomized study design, 209 patients were treated with FloSeal matrix sealant (FloSeal group) and 206 patients received alternative agents as topical hemostatic materials (comparison group). FloSeal is composed of a self-expandable gelatin matrix component and purified bovine thrombin. Comparisons included hemostatic patches or sponges composed of either oxidized regenerated cellulose or purified porcine skin gelatin. Study endpoints were the following: rate of successful intraoperative hemostasis (identified by cessation of bleeding) and time required for hemostasis; overall postoperative bleeding; rate of transfusion of blood products; rate of surgical revision for bleeding; postoperative morbidity; and intensive care unit stay. RESULTS Statistically higher rates of successful hemostasis and shorter time-to-hemostasis were observed in the FloSeal group (p < 0.001 both). Time-to-event analysis confirmed this finding (p = 0.0025). Postoperative bleeding and rate of transfusion of blood products were statistically decreased in the FloSeal group (p < 0.001 both). Rates of revision for bleeding and of minor complications were not statistically different among groups in the overall cohort, but were significantly lesser in the FloSeal group if only patients with overt intraoperative bleeding are considered (p = 0.04 both). The advantages observed in the FloSeal group were not offset in patients undergoing systemic hypothermia. CONCLUSIONS The topical hemostatic agent used in the FloSeal group is effective in terminating intraoperative bleeding as an adjunct to traditional surgical methods for stopping bleeding. Its judicious use is associated with lesser need for transfusion of blood products and rate of revision for bleeding. Its cost-utility profile should be addressed in dedicated trials.

Incidence, determinants, and prognostic value of reverse left ventricular remodelling after primary percutaneous coronary intervention: results of the Acute Myocardial Infarction Contrast Imaging (AMICI) multicenter study

Aims Few data are available on the extent and prognostic value of reverse left ventricular remodelling (r-LVR) after ST-elevation acute myocardial infarction (STEMI). We sought to evaluate incidence, major determinants, and long-term clinical significance of r-LVR in a group of STEMI patients treated with primary percutaneous coronary intervention (PPCI). In particular, the role of preserved microvascular flow within the infarct zone in inducing r-LVR has been investigated. Methods and results Serial echocardiograms (2DE) and myocardial contrast study were obtained within 24 h of coronary recanalization (T1) and at pre-discharge (T2) in 110 reperfused STEMI patients. Follow-up 2DE was scheduled after 6 months (T3). Two-year clinical follow-up was obtained. Reverse remodelling was defined as a reduction >10% in LV end-systolic volume (LVESV) at 6 months follow-up. r-LVR occurred in 39% of study population. At multivariable analysis, independent predictors of r-LVR were an effective microvascular reflow within the infarct zone, the in-hospital improvement of myocardial perfusion, an initial large LVESV, and a short time to reperfusion. Cox analysis identified r-LVR as the only independent predictor of 2-year event-free survival. Combined events rate was significantly higher among patients without compared to those with r-LVR (log-rank test P < 0.05). Conclusion r-LVR frequently occurs in STEMI patients treated with PPCI and it is an important predictor of favourable long-term outcome. A preserved microvascular perfusion within the infarct zone is the major determinant of r-LVR.

Genetic control of postoperative systemic inflammatory reaction and pulmonary and renal complications after coronary artery surgery.

BACKGROUND Although some data suggest that the individual genetic predisposition for developing major or minor degrees of postoperative systemic inflammatory reaction may influence postoperative morbidity, this hypothesis has not been clinically tested to date. Methods and results The -174 G/C polymorphism of the promoter of the interleukin 6 gene was determined preoperatively in 111 consecutive patients submitted to primary isolated coronary artery bypass. The results of the genetic analysis were then correlated with the postoperative interleukin 6 levels and the development of postoperative renal and pulmonary complications. G homozygotes had significantly higher interleukin 6 levels postoperatively (P <.0001 for the difference between areas under the curve). These patients also had worse postoperative pulmonary and renal function. The mean perioperative difference in serum creatinine, potassium, and nitrogen was 0.82 +/- 0.34, 0.99 +/- 0.44, and 10.1 +/- 7.8 mg/dL versus 0.18 +/- 0.14, 0.15 +/- 0.48, and 2.6 +/- 4.1 mg/dL for GG versus non-GG carriers (P <.0001), respectively. The mean respiratory index at 6 and 12 hours was 2.9 +/- 0.8 and 2.8 +/- 0.3 versus 2.1 +/- 0.5 and 1.3 +/- 0.1, respectively (P <.0001). The mean duration of mechanical ventilation was 22.5 +/- 2.1 versus 12.7 +/- 6.7 hours (P <.01). A correlation was found between postoperative interleukin 6 levels and renal and pulmonary complications. CONCLUSION The interleukin 6 -174 G/C polymorphism modulates postoperative interleukin 6 levels and is associated with the degree of postoperative renal and pulmonary dysfunction and in-hospital stay after coronary surgery.

Coronary artery bypass grafting in type II diabetic patients: a comparison between insulin-dependent and non-insulin-dependent patients at short- and mid-term follow-up

BACKGROUND Diabetes is a well-established risk factor for coronary artery disease, and it is associated with an increased rate of early and late adverse events after myocardial revascularization by coronary artery bypass grafting. METHODS A prospective follow-up study was done to evaluate the short-term and mid-term outcomes of type II diabetic patients who had coronary artery bypass grafting at our institution between 1996 and May 1999. A total of 200 patients, 100 insulin-dependent diabetic patients (group I) and 100 non-insulin-dependent diabetic patients (group II), met the inclusion criteria of the study and were included in the clinical follow-up study. RESULTS The characteristics of the patients of the two groups were similar for baseline clinical angiographic and operative characteristics. In particular, no significant differences in cardiopulmonary bypass and aortic cross-clamping times were noted between the two groups. The number grafts per patient was similar between the two groups. There were no in-hospital deaths, but postoperative complications were different among the two series. In fact, 33% of patients in group I had at least one major complication compared with 20% in group II (p = 0.037). The cumulative number of complications was 148 in group I and 69 in group II, and the mean number of complications per patient was 4.5 and 3.5 in groups I and II, respectively. The major differences in perioperative complication rates were found in the need for prolonged (> 24 hours) ventilation, occurrence of respiratory or renal insufficiency, and mediastinitis. The mean length of stay in the intensive care unit and for total hospitalization were longer in group I than group II (4.3 +/- 2.8 days versus 2.8 +/- 2.7 days [p = 0.010] and 11.1 +/- 2.2 days versus 7.2 +/- 2.4 group II [p < 0.05], respectively). At long-term follow-up, group I patients had a significantly higher mortality rate (29% versus 10%, p < 0.001). Moreover, overall late cardiac and noncardiac complication rates were significantly higher in group I than II (37% versus 22%, p = 0.02). In the multivariate analysis including several preoperative and operative variables, treatment by insulin, advanced age (> 75 years), left ventricular dysfunction (left ventricular ejection fraction < 35%), and complex lesions at coronary angiography (American Heart Association lesion classification type C lesion) were found as independent predictors of increased mortality. CONCLUSIONS Our data show that patients with insulin-dependent type II diabetes who had coronary artery bypass grafting have a significantly higher rate of major postoperative complications with an extremely unfavorable short- and long-term prognosis. Diabetic patients on insulin treatment should be considered high-risk candidates for coronary artery bypass grafting and require intense perioperative and long-term monitoring. Further studies will be necessary to investigate whether such conclusions may be appropriate for newer surgical strategies such as off-pump operation.

Conventional Left Atrial Versus Superior Septal Approach for Mitral Valve Replacement

BACKGROUND This study was designed to evaluate the safety and effectiveness of the superior septal approach for routine mitral valve replacement. METHODS One hundred forty-six consecutive patients undergoing mitral valve replacement at our institution were randomly assigned to undergo the procedure using either the conventional left atriotomy or the superior septal approach. Postoperatively and during the follow-up, 12-lead electrocardiography, 24-hour Holter monitoring, and transthoracic and transesophageal echocardiography were performed in all patients. RESULTS The cardiopulmonary bypass and cross-clamp times were significantly higher in the superior septal group. No significant difference in blood loss was found between the two groups, and no residual atrial septal defect was found in patients in whom we used the superior septal approach. The maintainance of sinus rhythm at late follow-up and the incidences of postoperative arrhythmias and newly developed atrioventricular block were not significantly different between the two groups. CONCLUSIONS The use of the superior septal approach to the mitral valve is not associated with a greater incidence of rhythm disturbances or other complications. Because this approach provides optimal exposure of the valve and the subvalvular apparatus, it has been routinely adopted for use in patients undergoing mitral valve replacement at our institution.

Individualized surgical strategy for the reduction of stroke risk in patients undergoing coronary artery bypass grafting.

BACKGROUND This study was designed to evaluate the efficacy of a protocol of systematic screening of the ascending aorta and internal carotid arteries and individualization of the surgical strategy to the ascending aorta and internal carotid arteries status in reducing the stroke incidence among patients undergoing coronary artery bypass grafting. METHODS On the basis of a pre- and intraoperative screening of the ascending aorta and internal carotid arteries, 2,326 consecutive patients undergoing coronary artery bypass grafting were divided in low, moderate, and high neurologic risk groups. In the high-risk group dedicated surgical techniques were always adopted and the reduction of the neurologic risk was considered more important than the achievement of total revascularization. RESULTS The incidence of perioperative stroke in the high-risk group was similar to those of the other two groups (1.1 versus 1.3 and 1.1%, respectively; p = not significant); however, angina recurrence was significantly more frequent in the high-risk group. CONCLUSIONS The described strategy allows a low rate of perioperative stroke in high-risk patients undergoing coronary artery bypass grafting. Whether the reduction of the neurologic risk outweighs the benefits of complete revascularization remains to be determined.

Should severe monolateral asymptomatic carotid artery stenosis be treated at the time of coronary artery bypass operation

OBJECTIVE The optimal treatment of severe monolateral asymptomatic carotid artery stenosis (SMACS) in patients undergoing coronary artery bypass grafting (CABG) is still controversial. MATERIALS AND METHODS This study is based on the in-hospital and mid-term (>5 years) clinical results of a cohort of 139 consecutive CABG patients with SMACS operated at our Institution between January 1989 and December 1995. In the first 73 patients (no carotid surgery group), the SMACS was left untouched at the time of coronary surgery, whereas in the remaining 66 (carotid endoarterectomy group), the carotid stenosis was treated either immediately before or concomitantly with the CABG procedure (depending on the severity of the anginal symptoms). RESULTS The overall preoperative characteristics of the patients were comparable. The in-hospital results were similar between the two groups with regard to mortality, stroke and major postoperative complications. However, at mid-term follow-up, significantly more patients of the no carotid surgery group suffered cerebral events (transient or permanent) ipsilateral to the SMACS or the lesion had to be operated on. CONCLUSIONS The concomitant treatment (either staged or simultaneous) of SMACS at the time of CABG does not influence the in-hospital results, but confers significant neurological protection during the years after the operation.