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To define better the performance of the bileaflet St. Jude and the tilting-disc Medtronic-Hall valves, we retrospectively analyzed 122 patients (St. Jude, 80 patients; Medtronic-Hall, 42 patients) who received simultaneous aortic and mitral replacement from May 1984 until June 1994. The two groups were not different with respect to preoperative clinical and hemodynamic parameters and New York Heart Association functional class. The hospital mortality and late mortality were not significantly different. Risk analysis identified advanced age and previous myocardial revascularization as predictors of operative death. Follow-up was complete in 96 of 103 hospital survivors (93%) and was similar in both groups. The actuarial survival, linearized rates of valve-related complications, and actuarial freedom from valve-related complications were similar in both cohorts. The presence of coronary artery disease negatively influenced the actuarial survival after simultaneous aortic and mitral valve replacement. Postoperative New York Heart Association functional class was not significantly different in either group. These data indicate that the Medtronic-Hall and St. Jude prostheses are not significantly different with respect to their clinical performance and valve-related complications for simultaneous double-valve replacement.

To evaluate the effectiveness of tailoring aortoplasty used to treat fusiform aneurysms of the ascending aorta, we reviewed the results of operation in 17 patients. Nine patients had tailoring aortoplasty alone, and 8 patients had aortoplasty with Dacron wrap of the ascending aorta. Fourteen of 17 patients were discharged from the hospital, and 12 patients were alive at follow-up between 2 and 120 months. Of two late deaths, neither was due to aneurysmal disease. Actuarial survival at 1 and 10 years was 81% and 63%, respectively. In selected cases, tailoring aortoplasty can achieve long-term results comparable with those of resection and graft replacement of fusiform ascending aortic aneurysms.

A DENOSINE (ADO, MW = 267.24) is an endogenous nucleoside (Fig I), which is the end-product of highenergy adenosine triphosphatc (ATP) catabolism during reduced oxygen (02) supply/demand states resulting from hypoxia and ischemia.’ In regard to the cardiovascular system, ADO may be considered a self-protective hormone or autocoid, because it is secreted by myocardial cells during ischemiaihypoxia while having many beneficial effects against arrhythmias, myocardial ischemia. and reperfusion ischemia.‘-a Leung et al” have published the first preliminary evidence that 5aminoimidazole-4-carboxamide riboside (AICAR) infusion reduces the frequency of perioperative myocardial infarctions (PMI) during coronary artery bypass graft (CABG) by increasing endogenous ADO in ischemic myocardium. The following is a critical review of published Englishlanguage articles regarding residual myocardial injury and potential metabolic therapy with either ADO or AICAR during CABG surgery.

Surgical treatment for ischemic heart disease continues to evolve. The long-term benefit of coronary artery bypass grafting can be shown to extend for 15 to 20 years. The long-term patency achieved with internal thoracic artery grafts has extended the already good results of coronary artery bypass grafting. It is the surgeon's hope that the pursuit of multiple arterial grafting will further extend these results. Operations continue to increase in complexity and include a growing number of reoperations. Techniques to deal with these situations have continued to evolve so that the operative mortality remains low. The role of angioplasty in patients with multiple-vessel coronary artery disease has not been firmly established. However, increasing data indicate that in patients with triple-vessel disease and depressed ventricular function, complete surgical revascularization is the treatment of choice.

Background. The extent of proximal and distal aortic resection that should be performed for acute type A aortic dissections remains controversial. Methods. 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. Results. Operative mortality was higher for separate graft and valve (50% ± 16%) than for valve preservation (16% ± 5%) or composite grafts (20% ± 7%) (p 0.71). 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 (p > 0.15). Risk factors for late reoperation included a nonresected primary tear and Marfan syndrome (p < 0.05). Conclusions. 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.

The radial artery (RA) is used increasingly for myocardial revascularization. Having an ultrasonic dissector available in our unit, we began to use it for RA harvest with the impression that harvest spasm might be less for the new technique.We compared RA harvest using standard techniques (21 RA) with ultrasonic dissection (41 RA) in which all branches were divided between clips with scissors in the former and bleeding branches were clipped in the latter.Harvest times were not different. Conventional technique used 74+/-18 (mean +/- standard deviation) clips versus 3.2+/-4.3 clips (p0.001). In situ free flow was 17.2+/-20.7 mL/min for conventional technique versus 52.5+/-48.1 for ultrasonic (p0.001). Free flow after the proximal anastomosis to the left internal thoracic artery was 38.5+/-60.4 mL/min for conventional technique and 50.7+/-29.6 for ultrasonic (p = 0.008). Free flow 10 minutes after intraluminal papaverine was 78.5+/-45.9 mL/min for usual technique versus 102.8+/-51.7 for ultrasonic (p = 0.016). No patient required reoperation for bleeding.Ultrasonic dissection of the RA is associated with decreased RA spasm, good hemostasis, no additional harvest time, and has become our standard technique.

The Oxford International Symposium on myocardial preservation provided an appropriate milestone and impetus to survey one aspect of operative myocardial preservation, namely blood cardioplegia, and to contrast it with the more popular crystalloid cardioplegia. This review is by no means complete or exhaustive but represents my best effort to summarize important information that has accumulated in the literature as blood cardioplegia, and our understanding of it, has evolved. It is appropriate to compare blood and crystalloid cardioplegia with respect to biochemical and physiological differences. Clinical comparison has been limited, for the most part, to randomized studies, and a number of differences and details of clinical management of the two techniques have been omitted, either because they seemed unimportant or there was no good information that would allow an objective comparison of their significance. Hopefully, the reader will recognize the intent to focus on meaningful differences and similarities between the two techniques and to present them fairly.

The efficacy of coronary sinus cardioplegia administered into the right atrium has not been fully defined. Thirty-two consecutive patients undergoing elective myocardial revascularization were prospectively assigned to receive cold blood cardioplegia exclusively into the aortic root (15 patients) or the right atrium (17 patients). The two groups were similar with respect to age, ventricular function, severity of coronary disease, cross-clamp time, and mean infusate volume and temperature. Completeness of revascularization was greater in the aortic root cardioplegia group (p less than 0.007). The mean septal temperature and time to achieve electromechanical arrest was greater in the right atrial cardioplegia group (p less than 0.05). The right ventricular temperature and the release of myocardial isoenzyme were similar in both groups. Left and right ventricular stroke work index was preserved equally in both cohorts. Volume loading studies performed immediately after termination of bypass suggested better left ventricular function in the aortic root cardioplegia group. Myocardial performance with a loading challenge assessed late postoperatively was superior in the right atrial cardioplegia group (p less than 0.05). There were no differences between the groups with respect to clinical outcome. The data suggest that right atrial cardioplegia (1) possesses clinical safety equal to aortic root cardioplegia, (2) possesses inferior ventricular septal cooling, and (3) yields adequate preservation of both the right and left ventricles. We conclude that right atrial cardioplegia possesses no apparent advantage over aortic root delivery in the setting of elective myocardial revascularization.

A 63-year-old man had a 10 × 16-cm sternal mass 18 months after a second aortocoronary bypass operation. The resected lesion was a metastatic tumor of squamous histology. No primary tumor was found. The diagnostic work-up and treatment options are presented.

Prevention of ventricular fibrillation after aortic unclamping using lidocaine hydrochloride as an additive to cold potassium blood cardioplegia was studied prospectively in 46 patients undergoing elective myocardial revascularization. Patients were similar with respect to age, ventricular function, severity of coronary artery disease, cross-clamp time, completeness of revascularization, frequency of internal thoracic artery grafting, systemic temperature at the time of cross-clamp removal, and mean infusate volume and temperature. Patients receiving lidocaine blood cardioplegia (group 1, 23 patients) had a significant reduction in the incidence of ventricular fibrillation (22% versus 74%; p less than 0.0005) and in the mean number of cardioversion attempts required to defibrillate the heart (0.5 +/- 1.3 versus 1.9 +/- 0.97; p less than 0.0005) after cross-clamp removal compared with controls (group 2, 23 patients). There were no differences between the two groups postoperatively with regard to cardiac enzyme release, hemodynamic measurements, or clinical outcome. Patients receiving lidocaine blood cardioplegia tended to have a lower incidence of new postoperative atrial fibrillation (9% versus 26%). Ventricular function was preserved equally in both groups. We conclude that lidocaine is a safe additive to potassium blood cardioplegia and significantly reduces the incidence of ventricular fibrillation after aortic unclamping.

Noninvasive innovations have advanced the timing and precsion of diagnosis of acute dissection or enlarging aortic aneurysm. However, the need to perform coronary arteriography prior to surgical repair in these patients remains a question for many clinicians. This retrospective 10-year (1978 to 1988) review examined data of 54 patients undergoing urgent surgical repair of thoracic aortic tear, aneurysm, or dissection in our institution. Results of coronary arteriography and clinical variables (history of coronary artery disease, electrocardiographic abnormalities, surgical procedures, and in-hospital mortality) were tabulated. Twenty-seven patients had type A aortic dissection and 27 patients had type B. Twenty-four patients had aortic dissection or tear (type A or B) due to motor vehicle trauma. In patients with type A, a history and/or electrocardiogram suggestive of coronary artery disease was present in 16, in whom cardiac catheterization was performed in five. None required coronary bypass surgery or died. In the 11 patients with no clinical history of coronary artery disease or electrocardiographic abnormalities, six had cardiac catheterization, none had coronary artery disease, two had coronary reimplantation, and six died. Only 1 of the 27 patients with type A dissection had a perioperative myocardial infarction (a patient with a clinical history of coronary artery disease who did not undergo cardiac catheterization). In patients undergoing type B aortic repair, 10 had a clinical history or electrocardiogram consistent with coronary artery disease but only one underwent cardiac catheterization and subsequent coronary artery bypass graft surgery for coronary artery disease. Seventeen patients had no history of coronary artery disease, of whom only two had cardiac catheterization (no coronary artery disease, no deaths), with three deaths in the remaining 15—one with coronary artery disease found at autopsy. Death after aortic surgical repair in our series was most often due to postoperative bleeding complications without evidence of myocardial infarction. In patients with no prior history of coronary artery disease of electrocardiographic abnormalities, past and current surgical experience do not support routine use of coronary arteriography.

The prevalence and characteristics of silent myocardial ischemia as detected by 24-hour ambulatory electrocardiography ST-segment depression were prospectively assessed in 94 patients examined early (1 to 3 months) and 184 patients examined late (12 months) after coronary artery bypass grafting (CABG), and followed for a mean of 48 +/- 11 (range 4 to 62) months. The relation of ambulatory electrocardiographic silent ischemia to evidence of completeness of revascularization as defined by cardiac angiography performed 1 and 12 months after CABG, and to prognosis by follow-up of adverse clinical events was analyzed. Silent ischemia was detected early in 20% (19 of 94) and late in 27% (50 of 184) of patients, and showed a mean frequency of episodes ranging from 6 to 10 episodes/24 hours with a mean duration ranging from 15 to 23 minutes. The circadian distribution of episodes disclosed a significant peak of ischemic activity during the period of 6 A.M. to noon and a secondary peak between 6 P.M. and midnight (p less than 0.01 and p less than 0.001, respectively). Silent ischemia was not found by univariate analysis to be associated with graft or anastomotic site occlusions, low graft flow rates, grafted arteries with significant distal residual stenoses or ungrafted stenotic native coronary arteries. Kaplan-Meier analysis of time to cardiac event showed that silent ischemia was not predictive of an adverse clinical event in the early years after CABG. Cox regression analysis of 30 covariates only disclosed age (relative risk 1.06 [95% confidence interval, 1.01 to 2.94]) as having an effect on time to adverse clinical event.(ABSTRACT TRUNCATED AT 250 WORDS)

Limitations in the long-term patency of saphenous veins for bypass grafts have encouraged interest in the use of arterial conduits. The positive effect of an internal thoracic artery graft on survival has been accepted for more than a decade, but it has proven difficult to show additional benefit from additional arterial conduits; this is probably due to multiple factors, including inappropriate choice of target vessels, short follow-up, and inadequate numbers of patients. Recently, however, the positive effect of a second arterial graft was confirmed. It will probably be difficult to show a survival benefit from a third or fourth arterial graft, but we believe that complete arterial revascularization will result in improved long-term freedom from reintervention. Interest in arterial conduits for coronary artery bypass was primarily limited to the left internal thoracic artery until the mid-1980s, when enthusiasm for the use of bilateral internal thoracic arteries grew. More recently, the gastroepiploic artery, the inferior epigastric artery, and especially the radial artery have all found advocates. However, the original conduit--and the standard against which all others are compared--is the greater saphenous vein.