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Acute kidney injury (AKI) after cardiac bypass surgery (CABG) is common and carries a significant association with morbidity and mortality. Since minocycline therapy attenuates kidney injury in animal models of AKI, we tested its effects in patients undergoing CABG. This is a randomized, double-blinded, placebo-controlled, multi-center study. We screened high risk patients who were scheduled to undergo CABG in two medical centers between Jan 2008 and June 2011. 40 patients were randomized and 19 patients in each group completed the study. Minocycline prophylaxis was given twice daily, at least for four doses prior to CABG. Primary outcome was defined as AKI [0.3 mg/dl increase in creatinine (Cr)] within 5 days after surgery. Daily serum Cr for 5 days, various clinical and hemodynamic measures and length of stay were recorded. The two groups had similar baseline and intra-operative characteristics. The primary outcome occurred in 52.6 % of patients in the minocycline group as compared to 36.8 % of patients in the placebo group (p = 0.51). Peak Cr was 1.6 ± 0.7 vs. 1.5 ± 0.7 mg/dl (p = 0.45) in minocycline and placebo groups, respectively. Death at 30 days occurred in 0 vs. 10.5 % in the minocycline and placebo groups, respectively (p = 0.48). There were no differences in post-operative length of stay, and cardiovascular events between the two groups. There was a trend towards lower diastolic pulmonary artery pressure [16.8 ± 4.7 vs. 20.7 ± 6.6 mmHg (p = 0.059)] and central venous pressure [11.8 ± 4.3 vs. 14.6 ± 5.6 mmHg (p = 0.13)] in the minocycline group compared to placebo on the first day after surgery. Minocycline did not protect against AKI post-CABG.

Strategic planning is integral to any operation but complexity varies immensely and therefore the effort necessary to create the optimal plan. The previous three reports have discussed individual conduits and herein is an attempt to present approaches to common situations which the author favors. Although much has been learned over 45 years about use and subsequent behavior of venous and arterial grafts we continue to learn and, as a result, evolve new strategies or modify those now popular. Thus the reader must recognize that in spite of trying to be balanced and inclusive all surgeons have personal opinions and also prejudices which influence the approach taken and which may not be the optimal one for others or for the patient.

This is the third in a series on coronary artery bypass which reviews three alternative arterial conduits. The radial artery has become the most widely used of the three and accumulating experience demonstrates better patency at 10 years versus saphenous vein. Drawbacks are a long incision on the forearm, the propensity for spasm and persistent sensory disturbance in about 10%. The first is answered by endoscopic harvest which may yield a shorter conduit but reduces sensory nerve injury. Spasm is managed pharmacologically and by less harvest trauma. The gastroepiploic artery is used in situ and free and although the abdominal cavity is entered complications are minimal and patency compares favorably with the radial artery. Use of the inferior epigastric artery remains minimal and its similar length often requires composite use but limited patency data are supportive. Other arteries have had rare use and this is unlikely to change because the three presented here have significant advantages and acceptance.

The saphenous vein has been the principal conduit for coronary bypass grafting from the beginning, circa 1970. This report briefly traces this history and concomitantly presents one surgeons experience and personal views on use of the vein graft. As such it is not exhaustive but meant to be practical with a modest number of references. The focus is that of providing guidance and perspective which may be at variance with that of others and recognizing that there may be many ways to accomplish the task at hand. Hopefully the surgeon in training/early career may find this instructive on the journey to surgical maturity.

ObjectiveRadial artery harvesting has been questioned because of purported long-term circulatory consequences. Previous midterm Doppler ultrasonographic results are inconsistent regarding ulnar arterial effects. Flow-mediated vasodilatation more sensitively measures response to shear stress as index of arterial reactivity and function.MethodsWe contacted 231 patients who had undergone radial artery harvesting at least 10 years previously (mean follow-up, 12.9 ± 0.8 years). Subcohort of 25 volunteers (mean age, 69.2 ± 8.4 years) underwent ultrasonographic evaluation of ipsilateral (harvest) and contralateral (control) ulnar arteries. Flow-mediated vasodilatation compared changes in ulnar arterial diameters before and after occlusion.ResultsIn subcohort, peak systolic velocity of harvest ulnar artery was 0.82 ± 0.15 m/s, versus 0.63 ± 0.23 m/s on control side (P

The evolution of percutaneous intervention has reduced the prevalence of coronary bypass surgery in a patient population that is older, with more comorbidity and advanced coronary disease. Despite this less favorable group, perioperative mortality has continued to decline as the operation improves. The latter includes off-pump coronary grafting, smaller incisions, better intraoperative myocardial preservation, improving management of cardiopulmonary bypass, perioperative glucose control, and increasing use of arterial conduits as the radial artery comes of age and the gastroepiploic artery is reborn as a free graft. This brief review of the basics of coronary artery bypass is part experience with an effort to be fair-minded and balanced and to include that which is new and promising. It is imperative that we continue to innovate and distill the best from the old so that we can provide the optimal intervention for coronary artery disease.

Coronary artery bypass in 150 patients with angina has been accomplished with 225 IMA grafts and 85 saphenous vein grafts. There were 7 (4.7%) hospital deaths. Posterative catheterization in 85% of patients revealed that 9 (4.7%) IMA grafts and 11 (15%) vein graft had thrombosed. One-year catheterization in 32 patients (38 IMA grafts and 13 vein grafts) revealed no additional graft failures. The better patency of the IMA grafts appears to be related to their smaller size and therfore greater velocity of blood flow and freedom from intimal proliferation.

Enthusiasm for new therapeutic modalities frequently results in a ground swell of overuse, which recedes to leave a trough of negativism before a definitive level is established. In the case of CABG, the ground swell has become a 10-year flood tide, without an ebb, although ripples have marred the surface. It is generally agreed that suitable control populations are needed to determine the role of a therapy and that the best controls would arise from randomized prospective trials. At present, the best randomized trial is the VA study which has shown that operation does not enhance longevity for single vessel disease, but clearly does for left main coronary disease. In those individuals with two- and three-vessel disease, the VA study has not shown that surgical therapy is better than medical treatment. However, three other studies containing patients selected by the VA criteria indicate that operation provides significantly greater longevity for patients in these two categories. Acceptance of this position requires acknowlegement of the validity of the VA study and the comparison of extramural concurrent surgical series.

These data would suggest that hypothermia combined with potassium cardioplegia enhances protection of the ischemic myocardium over other available techniques. The ideal conduct of this myocardial protection is not yet apparent but certain aspects are worthy of emphasis. (1) With the onset of ischemia cardioplegia should be immediately induced to abolish contractile activity and conserve energy. An advantage of blood cardioplegia is that there is no ischemia or it is trivial priorto cardioplegia. (2) The greater the degree of myocardial cooling the better. Although a myocardial temperature of 20 degrees C can commonly be achieved with perfusion hypothermia and topical hypothermia, it is possible to reduce myocardial temperature to 10 degrees C or lower with these same modalities. Because perfusion hypothermia provides fairly uniform rapid myocardial cooling, this should be maximally utilized by cooling of the systemic perfusate to 20 degrees C and cooling the cardioplegic infusate to 4-10 degrees C. Cardiac hypothermia should be maintained with crushed ice made from electrolyte solution or irrigation of the pericardial sac with cold electrolyte solution. The greater the degree of systemic hypothermia the less tendency for the myocardium to warm. (3) The ideal concentration of potassium is unknown at this time with a range of 15-40 mEq/l having been utilized without apparent potassium injury. (4) The ideal composition of the vehicle may never be defined and may not be of great importance. Whole blood would appear to offer physiological and pragmatic advantages over asanguinous vehicles. (5) The safe duration of ischemia has been moderately well defined. 1 h is well tolerated in the dog using profound cardiac hypothermia, whereas 30-45 min with lesser degrees of hypothermia is acceptable. When the interval of ischemia is to be 2 or 3 h reinfusion of potassium every 20-30 min has proven safe both experimentally and clinically.

Objective The radial artery has more smooth muscle in its wall than the other arterial conduits and is known to be vasospastic. Because it is frequently necessary to use vasoconstrictors early after coronary bypass surgery we investigated the effects of phenylephrine on conduit flow in this setting. Methods Thirty patients undergoing coronary artery bypass with all arterial conduits in which the radial artery was used as a T-graft were randomly assigned to receive intravenous infusions of normal saline (n = 10); nitroglycerin, 0.5 μg · kg · min (n = 11); or nicardipine, 0.5 μg · kg · min (n = 9), beginning early in the operation. After discontinuation of cardiopulmonary bypass and achievement of stable hemodynamics, control measurements were obtained, and this was followed by phenylephrine infusion to achieve a 20% increase in mean arterial pressure, after which the measurements were repeated. Results Mean radial artery flow increased similarly in all groups: normal saline, 40% ± 25%; nicardipine, 37% ± 27%; nitroglycerin, 48% ± 36% ( P = .533). Comparable changes occurred in arterial pressure and systemic vascular resistance, whereas the cardiac index remained unchanged. Conclusion Radial artery blood flow increases when the mean arterial pressure is increased with phenylephrine. There was no evidence of a conduit vasoconstrictive effect, which could limit or reduce conduit flow. Vasocontriction with phenylephrine is appropriate to provide adequate perfusion pressure for radial artery grafts.

Despite a known survival benefit with the use of the left internal mammary artery, it is used less frequently in women when compared with men. This study evaluated the hypotheses that the radial artery graft is used less frequently in women compared with men, that the radial artery is smaller in women compared with men, and that the use of the radial artery influences operative mortality and long-term survival in women.The use of a radial artery graft was evaluated in 2,633 patients who underwent isolated coronary artery bypass. Radial artery size and flow were compared in 207 patients who had intraoperative radial artery diameter and flow measurements. Propensity scoring was utilized to compare short- and long-term outcomes in a matched cohort of 588 women.Of 862 women (33%) who had isolated coronary artery bypass grafting, only 301 (35%) received a radial artery graft versus 44% of men (786 of 1,771, p0.001). Radial artery size and flow were significantly less in women. Operative mortality was not different between women with a radial artery graft and women without; however, 5-year survival was significantly better in women with a radial artery graft than in those without.Women received fewer radial artery grafts than men. Radial artery size and flow were significantly less in women than in men. Use of a radial artery graft did not influence operative mortality among women. However, 5-year survival among women who received a radial artery graft was significantly better than among women who did not.

Complete revascularization is important in young patients undergoing coronary artery bypass grafting, but this principle remains less absolute in elderly patients. The purpose of this study was to determine how complete revascularization influenced long-term survival after coronary artery bypass grafting in octogenarians.From 1986 to 2003, 500 consecutive patients 80 to 94 years of age underwent coronary artery bypass grafting. Complete revascularization was defined as placement of at least one graft to each of the three major vascular regions that included a 50% diameter lesion. Revascularization was complete in 400 (80%) patients and incomplete in 100 (20%) patients. Mean (+/- standard deviation) follow-up was 51 +/- 41 months and was 99% complete (2,102 total patient-years).Operative mortality was 8% +/- 2% (+/-95% confidence interval) and was statistically lower with complete (7% +/- 3%) versus incomplete (13% +/- 7%) revascularization (p0.05). Of 459 operative survivors, there were 261 late deaths. Multivariate regression analysis identified six independent predictors of late death: earlier operative year, male sex, peripheral or cerebrovascular disease, congestive heart failure, and incomplete revascularization (p0.03 for all). Excluding operative deaths, mean survival (Kaplan-Meier) was 82 months with complete revascularization compared with 65 months with incomplete revascularization (p0.008). Survival was 62% +/- 3% with complete versus 45% +/- 6% with incomplete revascularization at 5 years and 39% +/- 3% with complete versus 25% +/- 6% with incomplete revascularization at 8 years (p0.008).In octogenarians undergoing coronary artery bypass grafting, complete revascularization correlated with improved long-term survival, increasing mean survival by almost 25% compared with incomplete revascularization.

The purpose of this study was to compare operative mortality and midterm outcome of patients with ischemic mitral regurgitation (MR) undergoing either coronary artery bypass grafting (CABG) alone or CABG with mitral valve (MV) repair.From 1996 to 2001, 51 consecutive patients underwent CABG with MV repair for ischemic MR. All patients in this group were matched to similar patients with ischemic MR undergoing CABG alone during the same 6-year period using propensity analysis (considering 24 covariates, including severity of MR and New York Heart Association [NYHA] class).Propensity score matching yielded 51 closely matched control patients. Preoperative MR severity was 3+ or 4+ in 94% of CABG with MV repair and 96% of CABG-alone patients, and 86% of patients in each group were NYHA class III or IV. Operative mortality was 3.9% +/- 2.8% in both groups. Survival was also similar between CABG with MV repair and CABG alone at 1 year (84% +/- 5% versus 82% +/- 5%) and 3 years (70% +/- 7% versus 71% +/- 7% (p = 0.43). Among survivors, NYHA class improved at follow-up (50 +/- 20 months) from 3.4 +/- 0.7 to 1.7 +/- 1.0 for CABG with MV repair (p0.001) and from 3.4 +/- 0.7 to 1.8 +/- 1.0 for CABG alone (p0.001).Operative mortality, midterm survival, and late functional class were similar between two well-matched groups of patients undergoing CABG for ischemic MR, differing only in the addition of MV repair. Whereas MV repair can be added safely to CABG in this group of high-risk patients without increasing mortality, its impact on late survival and functional class may be limited.

The first three decades of coronary artery surgery have provided the foundation for the next century of this evolution. It is apparent that a multitude of events including the development of cardioplegia, improving surgical instrumentation, technological advances including endoscopic approaches and computer assisted robotics and biologic discoveries such as the role of the endothelium have provided the underpinnings for improved surgical outcomes. However, the single most important determinant of late results is the type of bypass conduit used for grafting. Thus, use of the left internal thoracic artery (ITA) grafted to the left anterior descending coronary is a more important determinant of survival than is any other factor (progression of coronary artery disease, increased age, poor left ventricular function, diabetes, female gender and offpump operations).1,2 Use of two ITAs provides further benefit3–8 and it is likely that three or more arterial conduits will be shown to be advantageous in this regard in due time. Japanese cardiothoracic surgeons have made significant contributions to the continuing evolution of coronary bypass surgery and particularly to the advance of arterial conduits. This report will address those contributions to this evolution.

Objective: The purpose of this study was to evaluate the effect of target vessel characteristics on radial artery patency when used as a composite T graft. Methods: Between October 1993 and March 2001, 1022 patients underwent coronary bypass with the internal thoracic artery–radial artery composite T graft. Of these, angiography has been performed on 109 patients at a mean 27.1 months (range, 2-70 months) postoperatively for symptoms of ischemia. By means of Cox proportional hazard models, the relationships between anastomotic patency and target vessel location, proximal stenosis, target diameter, and quality were assessed. Results: A total of 231 radial artery anastomoses were evaluated. The mean stenosis for patent anastomoses was 82% compared with 71% for occluded anastomoses (P

Objective: To assess the incidence of myocardial ischemia in patients receiving radial arterial and left internal thoracic arterial conduits (RA+LITA) during the postrevascularization period. Design: Nonrandomized observational sequential cohort. Setting: University hospital. Participants: Thirty adult patients, scheduled for elective coronary artery bypass graft surgery with RA+LITA, compared with 30 patients who received saphenous vein graft and left internal thoracic arterial conduits. Interventions: None. Measurements and Main Results: Myocardial ischemic episodes were defined as reversible ST-segment depressions or elevations ≥1 mm and ≥2 mm at J +60 msec and lasting ≥1 minute using 2-channel Holter monitoring. During the post-cardiopulmonary bypass period, a significantly higher number of patients with ≥2 mm ischemic episodes (21.7%; p = 0.015) and higher number of ≥2 mm ischemic episodes per hour (0.19 ± 0.4 episodes/hr; p = 0.03) were observed in the radial artery group versus the comparison group (0% of patients and 0 episodes/hr). During the postoperative period (24 hours), a significantly longer duration of ≥2 mm ischemic episodes was observed in the radial artery group (24 ± 33 minutes v 8.4 ± 21 minutes; p = 0.046). Radial artery graft, preoperative calcium antagonists, and pulmonary arterial mean pressure were independent predictors of the duration and area under the ST-segment curve of ≥2 mm ischemic episodes during the postoperative period. Conclusion: There is an association between the use of the radial artery graft and the incidence and severity of ≥2 mm postrevascularization ischemic episodes. Copyright © 2001 by W.B. Saunders Company

The extent of proximal and distal aortic resection that should be performed for acute type A aortic dissections remains controversial.From 1984 to 1999, 119 patients underwent repair of an acute type A dissection. Distal resection was to the ascending aorta in 78 (66%) and hemiarch in 41 (34%) patients. Proximally, the aortic valve was preserved in 69 (58%) patients, 40 (34%) underwent composite valve grafting, and 10 (8%) underwent separate graft and valve replacement.Operative mortality was higher for separate graft and valve (50%+/-16%) than for valve preservation (16%+/-5%) or composite grafts (20%+/-7%) (p0.05). Hemiarch replacement did not increase operative risk compared to distal reconstruction to the ascending aorta (17%+/-6% versus 22%+/-5%, p0.71). At 10 years, freedom from reoperation was 81%+/-7% and long-term survival was 60%+/-8%, but neither was related to the proximal or distal surgical technique (p0.15). Risk factors for late reoperation included a nonresected primary tear and Marfan syndrome (p0.05).An aggressive surgical approach, including a full root or hemiarch replacement, is not associated with increased operative risk and should be considered when type A dissections extensively involve the valve, sinuses, or arch.

Background . Proximal anastomosis of the radial artery to the side of the internal thoracic artery (ITA) permits complete arterial revascularization in most patients, with the aim of improving long-term results of coronary artery bypass through greater long-term graft patency. The short-term results, however, have yet to be defined. We therefore reviewed our early experience with this grafting strategy. Methods . Between October 1, 1993, and September 1, 1998, 649 patients aged 30 to 85 years (mean, 60 ± 10 years) had primary coronary artery bypass using an ITA and radial artery in a T-graft configuration. Left ventricular function was severely depressed (ejection fraction Results . A total of 937 distal anastomoses were performed with the left ITA (1.4 per patient) and 1,452 with the radial artery (2.2 per patient). There was one perioperative death (0.2%). There were 32 (5%) q-wave myocardial infarctions, and 14 patients (2%) had transient low output syndrome. There was one episode of hypoperfusion corrected by lengthening the left ITA. Angiography for clinical indications in 27 patients 1 to 35 months postoperatively (mean, 9.5 ± 8.3 months) demonstrated a distal anastomotic patency of 100% for ITA and 82% for radial artery grafts. Conclusions . Complete arterial revascularization can be achieved with an ITA and radial artery T-graft with low operative risk and acceptable early patency. These results support the continued investigation of this grafting strategy.

A human sternum with an imbedded arrowhead (Fig 1) from Patagnoia presents a dramatic image fit to make several points regarding life, medicine, and surgery. Things are not always what they seem (the arrow enters the inner side of the sternum and therefore crossed the chest). Life was as fragile then as it is today. New forms of trauma have replaced, but not completely, the arrow, and new diseases, witness acquired immunodeficiency syndrome, continue to arise or be recognized. Although the interval from then to now is great, the messages are timeless. My message is not timeless but focuses on two generations of physicians (dad and me), a decade of change, and the next generation. In less than a decade profound changes in the structure and economics of medical practice have surpassed those of the preceding 150 years. As I look back on my 32 years of practice that came after 13 years in education, training, and military service after college, I thought it might be appropriate to reflect on these changes and how they may affect physicians in the future. I was fortunate to have a father who practiced medicine in a blue collar community of ten thousand people, that was built around a United States naval ship yard. I was well aware of my father’s profession from an early age but did not participate in it as some sons might. I was occasionally exposed to the “evils of socialized medicine” through conversations between my father and other physicians. I also learned that the American Medical Association was solidly against this form of medical practice, which I did not fully comprehend. At that time it seemed a far off possibility and not particularly threatening even as I considered pursuing medicine as a career. It was during college that I decided that medicine would be a good career, for several reasons. I had a personal health problem that I wanted to research and correct for myself and others. There seemed to be a good market for physicians. Providing care was satisfying to one’s own mind and was associated with respect from the community. And if one were diligent and even modestly successful one would not starve. Medical school taught me enough to engender a new respect for my dad, who delivered babies, set fractures in his office, and then developed the x-rays of the same between pediatric patient visits, performed major abdominal or gynecologic operations in the morning before heading to the office, managed to make house calls at mundane as well as odd hours, and speak with patients on the phone in midst of family dinners (the phone was in its place beside the kitchen table where we ate). At that time I could recall Sunday drives in the country when father would point out a farmhouse where he had delivered a baby, where he had treated a patient with heart failure, or relate that he had to back his model-T Ford up the hill to another house as low gear did not provide enough power to make the grade. Mother told me how wonderful it was when the bridge was built across Port Washington Narrows in 1932 so that instead of a 10minute ferry ride it was a short drive across the bridge to make a house call and it saved a 1-hour drive home when dad missed the last ferry in the evening. These vignettes from the practice of a solo practitioner engaged in the great American fee-for-service tradition that existed from the founding of our country until recently are uncommon today except in very rural or remote areas. Occasionally my dad would mention that some patients had no money or not enough to pay for services, which never seemed to be a problem for him. The only vexation that I perceived was on occasion when such a patient would become unusually demanding of his time, such as a lengthy phone call while we were eating. Some less-well-off patients, but also those who did pay, were grateful in other ways by bringing something from the garden, the beach, the water, or something crafted by hand and dropped off at the office or our home. In my clinical years at the University of Washington Presented at the Forty-fifth Annual Meeting of the Southern Thoracic Surgical Association, Orlando, FL, Nov 12–14 1998.

To better define the merits of the bileaflet and tilting-disc valves, we prospectively randomized 102 patients whose age, 57 years; range, 11 to 85 years) to receive either the St. Jude (n = 55) or the Medtronic-Hall (n = 47) mitral valve prosthesis between September 1986 and May 1991. The two groups were not different with respect to preoperative New York Heart Association class, incidence of mitral stenosis and insufficiency, angina score, extent of coronary artery disease, ventricular function, completeness of revascularization, or cross-clamp or bypass time. The hospital mortality (14.5% versus 10.6%, St. Jude versus Medtronic-Hall) and late mortality (7.3% versus 2.1%) were not significantly different. Follow-up was complete in 84 of 89 hospital survivors (94%) with a mean of 26 months (range, 1 to 60 months). The linearized rates of valve-related events and the 3-year actuarial survival demonstrated no significant differences between both cohorts. Comparison of the clinical outcome and echocardiographic parameters obtained at the time of follow-up demonstrated no significant differences between the two prostheses. These data indicate that the Medtronic-Hall and St. Jude mitral prostheses are similar with respect to their rates of valve-related complications and hemodynamic profiles. This study suggests that there is no difference between the St. Jude and Medtronic-Hall prostheses with regard to early clinical performance or hemodynamic results and therefore does not support the preferential selection of either prosthesis.

The ideal temperature for blood cardioplegia administration remains controversial.Fifty-two patients who required elective myocardial revascularization were prospectively randomized to receive intermittent antegrade tepid (29 degrees C; group T, 25 patients) or cold (4 degrees C; group C, 27 patients) blood cardioplegia.The two cohorts were similar with respect to all preoperative and intraoperative variables. The mean septal temperature was higher in group T (T, 29.6 degrees +/- 1.1 degrees C versus 17.5 degrees +/- 3.0 degrees C; p0.0001). After reperfusion, group T exhibited significantly greater lactate and acid release despite similar levels of oxygen extraction (p0.05). The creatine kinase-MB isoenzyme release was significantly lower in group T (764 +/- 89 versus 1,120 +/- 141 U x h/L; p0.04). Hearts protected with tepid cardioplegia demonstrated significantly increased ejection fraction with volume loading, improvement in left ventricular function at 12 hours, and decreased need for postoperative inotropic support (p0.05). The frequency of ventricular defibrillation after cross-clamp removal was lower in this cohort (p0.05). There were no hospital deaths, and both groups had similar postoperative courses.Intermittent antegrade tepid blood cardioplegia is a safe and efficacious method of myocardial protection and demonstrates advantages when compared with cold blood cardioplegia in elective myocardial revascularization.

Anomalous origin of the left coronary artery from the pulmonary artery is rare and more so in the adult. Reimplantation of the left main coronary into the aorta is successful in early life, but it may be more difficult in the adult who had a previous repair. We report a successful reoperation of anomalous origin of the left coronary artery from the pulmonary artery in an adult patient using a left internal thoracic and radial artery "Y"-graft. Composite arterial grafting has become an established and straight forward technique in coronary surgery, and it is appropriate and recommended for congenital lesions in adults and at any age if necessary.

Chylothorax is a rare complication following coronary artery bypass graft surgery. We report a case of chylothorax that complicated a left internal thoracic artery harvest and review the literature regarding this subject.

This second report in the series on coronary artery bypass presents the authors experience and personal views on the internal thoracic artery (ITA) which date to 1966. There has been a very gradual evolution in the acceptance of this conduit which was initially compared with the saphenous vein and viewed as an improbable alternative to it. As is common with concepts and techniques which are 'outside the box' there was skepticism and criticism of this new conduit which was more difficult and time consuming to harvest for the surgeon who had to do it all. It was viewed as small, fragile, spastic and its flow capacity was questioned. Only a few surgeons employed it because of these issues and some of them would frequently graft it to the diagonal artery as it was thought not to supply adequate flow for the left anterior descending unless it was small. After a decade, angiographic data revealed superior patency to vein grafts. Even this evidence and survival benefit reported a few years later did not convince many surgeons that their concerns about limitations justified its use. Thus widespread adaption of the ITA as the conduit of choice for the anterior descending required another decade and bilateral use is only now expanding to more than 5% of patients in the US and somewhat faster in other countries.

Background— The radial artery is often used as the second arterial graft for coronary artery bypass grafting. Little is known about the differences in long-term patency between radial free and T grafts. This study was performed to determine long-term radial artery patency over a 15-year period. Methods and Results— Radial arteries were used as free grafts or T grafts for coronary artery bypass grafting over a 15-year period. Patients were contacted to determine if postoperative cardiac catheterization was performed and examination of any reports and films was performed. Grafts were graded as patent, luminal irregularity, or occluded. Each sequential graft was counted separately. Between September 1993 and December 2008, 13 926 patients underwent isolated coronary artery bypass grafting and 3248 patients had at least one radial artery graft used as a conduit. Catheterizations were performed at a mean of 7.4±3.8 years (range, 3 days to 14.4 years) on 372 radial artery grafts (103 free and 269 T) in 215 patients. Kaplan-Meier freedom from occlusion for radial free and T grafts at 1 and 10 years was 97.1% and 75.4% and 99.6% and 62.9%, respectively ( P =0.146 free versus T). Kaplan-Meier survival to 15 years was not statistically different between free and T graft patients ( P =0.5). Conclusions— In 215 patients with postoperative catheterization after coronary artery bypass grafting with a radial artery graft, radial free and T grafts had similar and acceptable long-term patency to support their use as a coronary artery bypass graft conduit.

From March 1990 through January 1992, 108 patients undergoing myocardial revascularization had one (91) or both (17) inferior epigastric arteries (IEA) used for myocardial revascularization. The internal thoracic artery (ITA) was used bilaterally in 87 patients. Of the 373 distal anastomoses, 210 (56%) were with the ITA, 130 (35%) with the IEA, and 12 (3%) with the gastroepiploic artery. Nineteen patients (18%) received 21 saphenous veins. When compared with the ITA, the IEA demonstrated a longer harvest time (36.5 vs 29.6 min, P0.0001), a shorter usable length (11.9 cm vs 16.5 cm, P0.001), and similar flow (49.7 cc/min vs 48.7 cc/min, P = NS). The operative mortality was 2.8%. Two deaths resulted from low cardiac output and the one remaining death from complications of a cerebral vascular accident. The most common major complication was respiratory insufficiency, which occurred in 11 patients (12%). There were two sternal infections (2%), and two abdominal wound infections (2%), none of which were fatal. The IEA is an acceptable additional arterial conduit. It can be safely employed with one or both ITAs. Short-term and long-term patency must be established before preferential use of this conduit is advised.

Background The internal thoracic artery (ITA) and inferior epigastric artery (IEA) may be used as conduits for myocardial revascularization. Harvesting the ITAs and IEAs can lead to clinically significant ischemia of the anterior abdominal wall. Methods We created a registry with data from 108 patients receiving myocardial revascularization with 1 or greater ITA and (or) 1 or greater IEA. After revascularization, patients were followed to document their outcomes during hospitalization. We sought to identify risk factors for tissue necrosis in these patients. Results All patients had 1 (84%) or 2 (16%) IEAs harvested. Both ITAs were utilized in 81% of patients; 19% had only the left ITA harvested. All patients in whom 2 IEAs were harvested also had 2 ITAs harvested (17 of 108). Of these 17 patients, 2 (12%) developed abdominal wall necrosis. Only patients who had bilateral ITA and bilateral IEA harvest experienced this complication. Conclusions Bilateral harvest of ITAs and IEAs results in a moderate risk of clinically significant abdominal wall necrosis. The extent of tissue loss may involve skin, muscle, and fascia, but the peritoneum and posterior rectus sheath remained intact in both affected patients in this series. These data may be most valuable to those who contemplate an abdominal operation in a patient who has had one or more of their ITAs or IEAs taken.

The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacement for aortic stenosis alone or in combination with myocardial revascularization has not been fully defined. Sixty-three patients undergoing elective aortic valve replacement received cold potassium blood cardioplegic solution via either the aortic root (36 patients) or the coronary sinus (27 patients). The patients were similar with respect to age, degree of aortic stenosis, ventricular function, severity of coronary artery disease, crossclamp time, completeness of revascularization, and mean volume and temperature of the infusion solution. The mean septal temperature and the release of myocardium-specific isoenzyme in the first 2 hours after crossclamp removal was higher in the retrograde group (p horac C ardiovasc S urg 1992;104:130–8)

To determine the efficacy of ventricular closure techniques, we reviewed our experience with 62 patients who survived the repair of aneurysms of the anterior wall of the left ventricular from 1984 through 1989. Forty of these patients underwent aneurysm repair by standard linear closure and 22 by a circular closure technique. After a mean follow-up interval of 3 years, there were no demonstrable differences in angina class, New York Heart Association functional classification, or survival. In 41 surviving patients, postoperative left ventricular dimensions and function were satisfactorily evaluated by standard echocardiographic measurements. No significant differences were found in postoperative long-axis left ventricular systolic diameter or in short-axis systolic or diastolic areas. There was a significantly larger long-axis diastolic diameter in the circular closure group; however, there was no difference in this parameter when the ratios of postoperative to preoperative lengths were compared. Further intragroup comparisons demonstrated an increase in short-axis areas postoperatively within the circular closure group in contrast to a decrease in patients in the linear closure group; these changes were not statistically significant. There was no significant difference in postoperative ejection fraction between the two closure groups, although minor reductions were found in the circular closure group. These data demonstrate no significant difference between the linear and circular closure techniques with respect to standard echocardiographic parameters, functional classification, and survival. (J T horac C ardiovasc S urg 1992;103:841-8)

Controlled dilation of the internal thoracic artery with a balloon catheter has been reported to effectively treat intraoperative arterial spasm. It has been shown in laboratory animals that dilation of the internal thoracic artery at prescribed shear force levels will not cause intimal damage. Using scanning electron and light microscopy, we have examined the effects of calibrated balloon dilation on the endothelium of the human internal thoracic artery. In 10 patients with bilateral internal thoracic artery grafting, the artery was dilated with a Fogarty IMAG balloon catheter (Baxter Healthcare Corporation, Edwards Division, Santa Ana, Calif.) that was withdrawn at tensions of 20 or 30 gm. Arterial segments and nondilated control specimens were prepared for scanning electron microscopy. The intimal surface of each internal thoracic artery was evaluated by assigning a score (from 0 to 3) to 10 examined scanning electron microscopy fields; subsequently the arterial tissue was viewed by light microscopy with paraffin-embedded sections stained for elastic tissue. Arteries were obtained from three additional patients so that the microscopic appearance of the arteries could be observed after rough manipulation or removal of the balloon without shearing. The results of this study are as follows: (1) By scanning electron microscopy, dilated internal thoracic arteries yielded consistently higher scores than the control arteries, reflecting severe, tension-dependent alterations of the endothelium, which included marked desquamation of endothelial cells, with extensive areas of complete denudation and pronounced attachment of platelets to these areas; (2) endothelial injury occurred by inflation alone, without shearing by the inflated balloon; (3) by light microscopy, the internal thoracic arteries showed (a) fenestrations of the internal elastic lamina with occasional transmigration of smooth muscle cells through these gaps and (b) foci of intimal thickening without overt atherosclerotic lesions. We conclude that the endothelium of human internal thoracic arteries is highly vulnerable to balloon dilation, which can severely injure the intimal surface. For this reason we prefer not to include this procedure in our protocol for preparing the internal thoracic artery. (J T horac C ardiovasc S urg 1992;103:375—80)

From March 1990 through January 1991, 47 patients undergoing myocardial revascularization had one (37) or both (10) inferior epigastric arteries (IEA) used as a conduit for bypass with 62 distal anastomoses. The internal thoracic artery (ITA) was used bilaterally in 41 patients and unilaterally in 6 with 100 distal anastomoses. Five patients had a single saphenous vein graft. In total, 167 anastomoses (3.55 per patient) were performed. Single IEA grafts were harvested through a paramedian incision and bilateral grafts, a midline incision. Harvest time was 36.5 minutes for IEA grafts and 29.6 minutes for ITA grafts (p less than 0.0001). Graft length was 11.9 cm for IEA grafts and 16.5 cm for ITA grafts (p less than 0.0001). Distal graft diameter was 2.0 mm for IEA grafts and 2.1 mm for ITA grafts (p less than 0.01). Graft flow was 49.7 mL/min for IEA grafts and 48.7 mL/min for ITA grafts. Microscopic assessment of segments of both the IEA and ITA from 14 patients revealed similar internal elastic laminae and an equal number of fenestrations. Combined intimal and medial thickness was comparable in both conduits. Medial elastic tissue was more prominent in ITA grafts and lacking in eight of the 14 IEA grafts. Gross plaque formation was noted in the proximal 1 to 3 cm of 50% of IEA grafts, but the lumen was not compromised and microscopic thickening was minimal. An unexpected finding was medial calcifications (Mönckeberg's disease) in two of the 14 IEAs without associated atherosclerosis. There was one hospital death, one abdominal wound infection, and one instance of fat necrosis superficial to the sternum.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrasonic decalcification of the aortic valve was performed in 22 elderly patients with critical aortic stenosis (aortic valve areas less than 0.8 cm2) as an alternative to prosthetic valve replacement. All of the patients had symptoms. The mean New York Heart Association class was 3.3 +/- 0.9. Adequate decalcification with restoration of leaflet mobility was achieved in all patients, including seven with bicuspid aortic valves. Leaflet perforation occurred and was successfully repaired in five patients. Ten patients underwent concomitant myocardial revascularization. There were two operative deaths (9%) and three late deaths. Echocardiograms were obtained preoperatively, postoperatively, and at 6 months. The mean aortic valve area increased significantly from 0.72 +/- 0.17 to 1.42 +/- 0.31 cm2 (p less than 0.001) and the peak gradient decreased from 74 +/- 34 to 25 +/- 13 mm Hg (p less than 0.001). At 6 months the aortic valve area (1.29 +/- 0.48 cm2) and peak gradient (31 +/- 12 mm Hg) continued to be significantly better than the preoperative measurements (p less than 0.001), but the 6-month aortic valve area was slightly decreased and the gradient increased when compared with the immediate postoperative values (p less than 0.02). The prevalence of mild to moderate aortic insufficiency increased from 50% of the patients preoperatively to 87% at 6 months (p less than 0.05). Two patients subsequently required aortic valve replacement for restenosis and aortic insufficiency. Ultrasonic decalcification is effective in relieving aortic stenosis, but subsequent restenosis and insufficiency may limit its application.

From July 1, 1984, through June 30, 1989, after 1,259 open heart operations, 110 patients (8.7%) underwent 162 early reoperations either in the intensive care unit (144 procedures) or in the operating room (26 procedures). Reexploration for bleeding (49 procedures) (3.9%) and intraaortic balloon removal (50 procedures) (4.0%) were the two most common procedures. Ninety percent and 96% of these procedures, respectively, were performed in the intensive care unit. Mediastinal infections occurred in 4 (6.1%) of 66 patients undergoing repeat mediastinal operations for all indications. No infection occurred after reexploration for bleeding nor did mediastinal infection occur after reoperation in the intensive care unit. Postoperative death in these 110 patients was not related to reoperation except possibly in the case of 1 patient (0.9%). Average transit time to and from the operating room for patients returned there for reoperation was 89.7 minutes. Charges for procedures performed in the operating room were at least twice as great as for those performed in the intensive care unit. This experience supports expanded use of reoperation in the intensive care unit, as it is safe, effective, economical, and convenient.

One hundred consecutive patients who had coronary artery bypass grafting using both internal thoracic arteries (ITAs) and saphenous veins, operated on during a 3-year period between 1972 and 1975, have been compared retrospectively with a series of 100 patients operated on during the same period who had one ITA graft along with saphenous vein grafts. The two groups were similar with respect to age, sex, risk factors for coronary artery disease, angina class, extent of coronary artery disease, left ventricular function, number of coronary bypass grafts performed, and completeness of revascularization. Single ITA operative mortality was 2% and double ITA, 9% (p = NS). The mean follow-up of hospital survivors was 14.4 +/- 2.7 years; all but 7 patients had follow-up for at least 10 years. At 13 years, the actuarial patency of the right ITA was 85% and the left ITA, 82%. These data strongly suggest a survival benefit for patients with double ITA grafts among hospital survivors (74% versus 59%; p = 0.05). Patients receiving two ITA grafts had a significant freedom from subsequent myocardial infarction (75% versus 59%, p less than 0.025), recurrent angina pectoris (36% versus 27%, p less than 0.025), and subsequent total ischemic events (32% versus 18%, p less than 0.01). These data also suggest improved freedom from coronary artery interventional therapy (percutaneous transluminal coronary angioplasty and reoperation) when two ITA grafts were used. These results support the use of bilateral internal thoracic artery grafting in selected patients.

At present a rapid and profound change in myocardial revascularization has evolved from the work of Gruentzig. The recent technological advances have been so fast paced that there has not been ample time to fully assess each new facet of technology and pharmaceutics before another arrives. The interface between percutaneous intervention (PCI) and coronary artery bypass (CAB) is not well defined as previously so that continental, national and regional differences exist. The progress in PCI from balloon angioplasty to drug eluting stents has seen a progressive decline in restenosis and reintervention but relief of symptoms has not equaled that attained with CAB. Survival benefit for CAB over PCI has not been demonstrated in the many randomized clinical trials which are limited by selection of only 5-12% of potential patients so that higher risk patients and those with more extensive and complex coronary disease are excluded. These excluded patients are included in the registries where survival benefit for CAB over PCI is clearly evident. Situations less amenable to PCI include: left main disease; three vessel disease; vessels that are smaller, diffusely diseased or with distal lesions which are frequently associated with diabetes; ostial and bifurcation lesions; and coronary arteries that are tortuous, calcified or with very long lesions. It is in these situations that PCI does not provide revascularization equivalent to CAB. Surgeons must appreciate the success of PCI, acknowledge their reduced role in revascularization and strive to provide the best operation possible when the clinical situation demands it.

The purpose of this study was to identify patient subgroups in which prosthesis-patient mismatch most influenced late survival.Over a 12-year period, 1,400 consecutive patients underwent bioprosthetic (933 patients) or mechanical (467) aortic valve replacement. Prosthesis-patient mismatch was defined as prosthetic effective orifice area/body surface area less than 0.75 cm2/m2 and was present with 11% mechanical and 51% bioprosthetic valves.With bioprosthetic valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 68% +/- 7% mismatch versus 75% +/- 7% no mismatch, p0.02) but not older patients (p = 0.47). Similarly, with mechanical valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 62% +/- 11% versus 79% +/- 4%, p0.005) but not older patients (p = 0.26). For small patients (body surface area less than 1.7 m2), prosthesis-patient mismatch did not impact survival with bioprosthetic (p = 0.32) or mechanical (p = 0.71) valves. For average-size patients (body surface area 1.7 to 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with both bioprosthetic (p0.05) and mechanical (p0.005) valves. For large patients (body surface area greater than 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with mechanical (p0.04) but not bioprosthetic (p = 0.40) valves.Prosthesis-patient mismatch had a negative impact on survival for young patients, but its impact on older patients was minimal. In addition, although prosthesis-patient mismatch was not important in small patients, prosthesis-patient mismatch negatively impacted survival for average-size patients and for large patients with mechanical valves.

Background Complex use of arterial conduits has resurrected concerns about the adequacy of conduit flow. The T-graft is the extreme example of this trend. Our purpose was to identify the limitation of single source inflow and to compare flow capacity with completion coronary flow. Methods Between February 1999 and November 2001, 372 patients underwent total arterial revascularization with the T-graft alone. Intraoperative flows were recorded for each limb of the T-graft before and after distal anastomoses in 204 patients. Independent predictors of T-graft flow were identified by multivariate analysis. Results Free flow for the radial arterial (RA) limb was 161 ± 81 mL/min, the internal thoracic artery (ITA) limb 137 ± 57 mL/min (combined 298 ± 101 mL/min) versus simultaneous limb flow of 226 ± 84 mL/min giving a flow restriction of 24% ± 14%. Completion coronary flow was 88 ± 49 mL/min for the RA, 60 ± 45 mL/min for the ITA, and 140 ± 70 mL/min for both limbs simultaneously to give a flow reserve (vs simultaneous free flow) of 160% or 1.6. Independent predictors of completion RA limb flow are RA proximal diameter ( p = 0.005), number of anastomoses ( p = 0.018), and target stenosis ( p = 0.005). Conclusions A flow reserve of 1.6 compares favorably with an ITA flow reserve of 1.8 at 1-month postoperatively and 1.8 for both the ITA T-graft and the ITA/RA T-graft at 1-week postoperatively as reported by others. Proximal RA diameter and competitive coronary flow influence completion T-graft flow. These data quantitate the limitation of single source inflow of the T-graft configuration and support its continued use.

Background The purpose of this study was to determine the incidence of neurologic hand complications after radial artery harvesting and to compare the harmonic scalpel versus conventional cold scalpel technique. Methods From 1995 to 2000, 786 radial arteries were harvested from 782 patients for coronary artery bypass grafting. From 1995 to 1997, the conventional cold scalpel technique was used (422 patients), and from 1998 to 2000, the harmonic scalpel was used (360 patients). Mean follow-up was 4.2 ± 2.1 years and was 90% complete. Symptoms included thumb weakness or numbness, tingling, or pain in the hand. Results The incidence of neurologic hand complications was similar with both techniques (11.2% ± 3.5% cold, 11.0% ± 3.6% harmonic, p > 0.95), and in 19% (13 of 67 with symptoms) there was complete resolution within 1 year. Symptoms persisted long-term in 9.0% ± 3.2% cold scalpel and 9.0% ± 3.3% harmonic scalpel patients ( p > 0.81), but were considered a "constant and significant source of discomfort" in only 0.6% ± 0.9% cold scalpel and 1.4% ± 1.3% harmonic scalpel patients ( p > 0.41). Conclusions The incidence of adverse neurologic outcomes causing significant long-term discomfort in the hand was low using either the cold scalpel or harmonic scalpel technique. However, a significant number of patients had neurologic hand symptoms in both groups, and this should be included when discussing operative risks with the patient.

The radial artery (RA) can be used as either an aortocoronary (RA-Ao) or composite graft (T graft). Optimum use for the RA has yet to be established. We compared RA patency with these two techniques.Between October 1993 and June 2001, 1505 patients underwent coronary artery bypass grafting using the RA as either a composite (n = 1022) or RA-Ao graft (n = 483). Angiograms performed on 203 (13.5%) patients with signs or symptoms of ischemia at an average of 26.1 +/- 18.5 months postoperatively were reviewed.Patients with RA-Ao grafts had a greater incidence of postoperative angiography versus patients with composite grafts (19% versus 11%; p0.01). Patients receiving T grafts had a greater number of anastomoses per patient (4.1 +/- 0.6 versus 3.0 +/- 1.0; p0.01) and a higher incidence of total arterial revascularization (100% versus 41%; p0.01). Regardless of grafting strategy, patency was significantly worse for targets of the right coronary artery (58% T graft; 67% RA-Ao; p0.01 for both) and for targets with less than or equal to 70% stenosis (59% T graft; 57% RA-Ao; p0.01 for both). The site of proximal anastomosis failed to effect RA patency (relative risk, 1.2; 95% confidence interval, 0.7 to 1.8; p = 0.50).The site of the proximal anastomosis does not appear to influence patency. Both RA-Ao and composite conduits are sensitive to target location and stenosis. Advantages of composite grafting include greater conduit length and minimizing aortic manipulation at the expense of increased complexity and the potential for hypoperfusion. These factors should be considered when choosing an RA grafting strategy.

Fifteen patients who had coronary artery bypass grafting with the left internal thoracic artery (2 also had in situ right internal thoracic artery grafts placed) underwent catheterization for recurrent angina 15 to 21 years later. Angiographic assessment revealed widely patent conduits without evidence of conduit atherosclerosis. Translocation of the internal thoracic artery to the coronary circulation does not appear to be associated with accelerated atherosclerosis of the conduit, and freedom from serious conduit atherosclerosis can be anticipated for at least 20 years.

Enthusiasm for simulation early in cardiothoracic surgery training is growing, yet evidence demonstrating its utility is limited. We examined the effect of supervised and unsupervised training on coronary anastomosis performance in a randomized trial among medical students.Forty-five medical students were recruited for this single-blinded, randomized controlled trial using a low-fidelity simulator. After viewing an instructional video, all participants attempted an anastomosis. Subsequently, the participants were randomized to 1 of 3 groups: control (n = 15), unsupervised training (n = 15), or supervised training with a cardiothoracic surgeon or fellow (n = 15). Both the supervised and unsupervised groups practiced for 1 hour per week. After 4 weeks, the participants repeated the anastomosis. All pre- and posttraining performances were videotaped and rated independently by 3 cardiothoracic surgeons blinded to the randomization. All raters scored 13 assessment items on a 1 to 5 (low-high) scale along with an overall pass/fail rating.After the training period, all 3 groups showed significant improvements in composite scores (control: +0.52 ± 0.69 [P = .014], unsupervised: +1.05 ± 0.48 [P .001], and supervised: +1.10 ± 0.84 [P .001]). Compared with control group, both supervised (P = .005) and unsupervised trainees (P = .005) demonstrated a significant improvement. Between the supervised and unsupervised groups there were no statistically significant differences in composite scores.Practice on low-fidelity simulators enabled trainees to improve on a broad range of skills; however, the additional effect of attending-level supervision is limited. In an era of increasing staff surgeon responsibilities, unsupervised practice may be sufficient for inexperienced trainees.

In the initial decade of coronary surgery, serial angiography of internal thoracic artery grafts revealed increased caliber in some, decreased caliber in others, and "string sign" in a few, which was occasionally documented to be reversible. Although we speculated on possible causes of these changes, it was not until discovery of the endothelial role in modulating arterial diameter to maintain shear stress in a narrow range that we began to gain insight into the mechanisms responsible for remodeling of the arterial wall. This review provides a glimpse of the physiology and biology of arterial remodeling and summarizes observations on the various arterial conduits when subjected to flow alterations.