Mitral valve repair in the elderly: operative risk for patients over 70 years of age is acceptable.

AIM: Mitral valve repair for degenerative disease is widely accepted. Because of low risk and excellent late outcomes, surgical intervention is recommended increasingly early when repair appears possible. The place of repair vis a vis continued medical therapy in the elderly, however, is less well defined as there are scant data on their surgical risk. We reviewed our recent results with mitral valvuloplasty for degenerative disease with attention to the influence of age. METHODS: Thirty-day results of mitral valvuloplasty for degenerative disease between January 1996 and April 2000 were examined retrospectively. Patients with ischemic etiology were excluded. Results among those over age 70 years were compared with younger patients. RESULTS: Of 140 patients (78 men and 62 women) aged 27 to 91 (mean 62+/-13) years (44 gs;70 years of age), 61 underwent isolated mitral valvuloplasty, 71 mitral valvuloplasty and coronary artery bypass, and 8 mitral valvuloplasty with other procedures. By multivariate analysis preoperative cardiogenic shock (0.001), but not age, was as a risk factor for death. Among patients stratified by age gs; or <70, there were differences in atrial fibrillation (47.7% vs 29.2%, p=0.03), prolonged ventilation (31.8% vs 15.6%, p=0.03) and hospital stay (median 9.5, range 5-285 vs median 6.5, range 2-36, p=0.001), but not 30-day readmission (15.9% vs 22.9%) or death (5.2% vs 9.1%, p=0.49). CONCLUSION: Operative results for mitral valvuloplasty in the elderly are acceptable. Surgery should not be withheld on the basis of age alone.

The advantages of the Harmonic Scalpel for the harvesting of radial arteries for coronary artery bypass.

BACKGROUND: Improvements in replacement vessel harvesting techniques and antispasmodic agents since the 1970s have led to a resurgence of interest in the radial artery (RA) as a conduit for coronary revascularization. METHODS: This randomized study compared the Ultra Cision Harmonic Scalpel (HS) (Ethicon Endo-Surgery, Inc., Cincinnati, OH) and the cold steel scalpel (CSS) for harvesting radial arteries to be used in coronary artery bypass grafting (CABG) procedures. Men and non-pregnant women, aged 21 to 79 years, with myocardial ischemia or coronary stenosis who were scheduled to undergo coronary bypass were enrolled in the study. RESULTS: Harvesting of the radial artery by the Harmonic Scalpel required a significantly lower number of clips to control bleeding. There was no significant difference between the times required to harvest the artery with either device. There were no complications, malfunctions, or serious adverse events associated with the use of either device. CONCLUSIONS: The Harmonic Scalpel provides excellent control of bleeding compared to the cold steel scalpel, and its use permits bleeding to be controlled without the need for potentially damaging electrocautery. No clinically significant adverse events were associated with the use of the Harmonic Scalpel.

Midterm results of complete arterial revascularization in more than 1,000 patients using an internal thoracic artery/radial artery T graft.

OBJECTIVE: To report the authors' 7-year experience with the internal thoracic artery/radial artery (ITA/RA) T graft as the only conduits for myocardial revascularization in two- and three-vessel disease. SUMMARY BACKGROUND DATA: One and two arterial conduits provide increasing survival benefit for coronary grafting and reduce the need for reintervention. Exclusive use of arterial conduits may provide further benefit. METHODS: From October 1993 to November 2000, 1,020 patients underwent complete arterial revascularization with the ITA/RA T graft. The authors focus on the 909 having initial bypass, with a mean age of 60 and 20% age 70 or older. The incidence of triple-vessel disease was 73%, female gender 28%, diabetes mellitus 27%, peripheral vascular disease 11%, cerebrovascular disease 10%, and chronic obstructive pulmonary disease 6%; ejection fraction was less than 35% in 11%. Perioperative data were collected prospectively. Follow-up information was obtained at a mean of 35.4 months (range 1-88) and was 95% complete. RESULTS: There were seven (0.08%) deaths within 30 days of surgery. The incidence of perioperative infarction was 3.3%, low cardiac output 2.7%, stroke 2.2%, reoperation for bleeding 3.8%, and deep sternal infection 0.8%. The actuarial survival rate was 90% at 5 years, freedom from infarction was 94%, freedom from catheterization was 83%, and freedom from reintervention (angioplasty or reoperation) was 93%. CONCLUSION: The ITA/RA T graft for complete arterial revascularization is associated with a low rate of perioperative death and complications and 5-year survival and freedom from reintervention values consistent with other revascularization strategies.

Occurrence of myocardial ischemia immediately after coronary revascularization using radial arterial conduits.

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 >or=1 mm and >or=2 mm at J +60 msec and lasting >or=1 minute using 2-channel Holter monitoring. During the post-cardiopulmonary bypass period, a significantly higher number of patients with >or=2 mm ischemic episodes (21.7%; p = 0.015) and higher number of >or=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 >or=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 >or=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 >or=2 mm postrevascularization ischemic episodes.

Does the extent of proximal or distal resection influence outcome for type A dissections?

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 < 0.05). Hemiarch replacement did not increase operative risk compared to distal reconstruction to the ascending aorta (17%+/-6% versus 22%+/-5%, 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.

Influence of internal mammary artery grafting and completeness of revascularization on long-term outcome in octogenarians.

BACKGROUND: It has been well established that complete revascularization with internal mammary artery (IMA) grafting is important in young patients undergoing coronary artery bypass grafting (CABG). Applying these principles to octogenarians remains controversial. METHODS: From 1986 to 1999, 358 consecutive patients aged 80 to 94 years underwent CABG. Revascularization was complete in 291 (81%) and incomplete in 67 (19%). The IMA was used in 231 (65%) cases. RESULTS: Operative mortality was 7% +/- 1%, but was not statistically different with or without IMA grafting (IMA 5% +/- 2% versus no IMA 10% +/- 3%, p = 0.11) or complete revascularization (p > 0.41). Midterm survival improved with IMA grafting (70% +/- 3% versus 56% +/- 5% at 4 years, p < 0.03; 36% +/- 4% versus 29% +/- 5% at 8 years, p < 0.08), but was not significant beyond 8 years. Among 138 survivors, those with IMA grafts were more likely to be angina free (82% versus 53%, p < 0.001) and in New York Heart Association class I (60% versus 36%, p < 0.03). Survival, recurrent angina, and functional class were independent of completeness of revascularization (p > 0.21). CONCLUSIONS: IMA grafting improved survival, angina, and functional class of octogenarians, but complete revascularization did not have a similar impact.

Quality of life after aortic valve replacement at the age of >80 years.

BACKGROUND: The optimal management of aortic valve disease in patients >80 years old depends on functional outcome as well as operative risks and late survival. METHODS AND RESULTS: We retrospectively identified 133 patients (62 men, 71 women) aged 80 to 91 years (mean 84+/-3 years) who underwent aortic valve replacement alone or in combination with another procedure between January 1, 1993, and April 31, 1998. Demographics included hypertension 68%, diabetes mellitus 17%, and history of stroke 11%. Operative (30 day) mortality rate was 11%. Urgent or emergent surgery, aortic insufficiency, and perioperative stroke or renal dysfunction were risk factors for operative death by multivariable analysis. Intensive care unit and total hospital length of stay were prolonged at 6.2 and 14.7 days, respectively. Late follow-up between July 1, 1998, and November 1, 1999, was 98% complete. Actuarial survival at 1 and 5 years was 80% and 55%, respectively. Predictors of late mortality were preoperative or perioperative stroke, chronic obstructive pulmonary disease, aortic stenosis, and postoperative renal dysfunction. The mean New York Heart Association functional class for 65 long-term survivors improved from 3.1 to 1.7. Quality of life assessed with the Medical Outcomes Study Short Form-36 was comparable to that predicted for the general population >75 years old. CONCLUSIONS: Functional outcome after aortic valve replacement in patients >80 years old is excellent, the operative risk is acceptable, and the late survival rate is good. Surgery should not be withheld from the elderly on the basis of age alone.

Radial artery harvest: comparison of ultrasonic dissection with standard technique.

BACKGROUND: 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. METHODS: 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. RESULTS: Harvest times were not different. Conventional technique used 74+/-18 (mean +/- standard deviation) clips versus 3.2+/-4.3 clips (p<0.001). In situ free flow was 17.2+/-20.7 mL/min for conventional technique versus 52.5+/-48.1 for ultrasonic (p<0.001). 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. CONCLUSIONS: Ultrasonic dissection of the RA is associated with decreased RA spasm, good hemostasis, no additional harvest time, and has become our standard technique.

Multiple arterial grafts and survival.

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.

Reappraisal of coronary endarterectomy for the treatment of diffuse coronary artery disease.

BACKGROUND: The development of new technologies such as transmyocardial laser revascularization and, more recently, local delivery of angiogenic growth factors has refocused attention on the surgical management of diffuse coronary artery disease. In some cases, coronary endarterectomy is also technically feasible. To facilitate decision-making among these options, we reviewed our experience with coronary endarterectomy to determine the results to be expected with this more traditional approach. METHODS: A search of our computerized database identified 7,096 patients undergoing myocardial revascularization between January 1, 1986 and March 30, 1997, of whom 177 (2.3%) underwent endarterectomy of at least one coronary artery. Perioperative events were derived from the database. Follow-up information was obtained from patients at 3 months to 11.5 years (mean = 55.7 +/- 38.8 months) after surgery. RESULTS: Endarterectomy was performed on the right coronary artery (RCA) system in 100 patients, the left anterior descending (LAD) system in 52, the circumflex system in 18, and in multiple distributions in 7. The 30-day mortality was 7% for RCA, 0% for LAD, 17% for circumflex, and 14% for multi-system endarterectomy (p = 0.20). There were no statistically significant differences in perioperative myocardial infarction or ventricular dysrhythmia between these groups. Actuarial survival at 5 years was 76% for patients undergoing RCA endarterectomy and 75% for left sided (LAD or circumflex) endarterectomy (p = 0.91). At late follow-up, 74% (86/117) of survivors were angina-free, 6% (7/117) had undergone subsequent angioplasty, and 3% (4/117) had undergone subsequent surgery. CONCLUSIONS: Coronary endarterectomy can be accomplished with acceptable operative risk and good long-term results, even when applied in a highly selective manner. The results of novel therapies for diffuse coronary artery disease should be considered in the context of those achievable with more traditional approaches.

The continuing evolution of arterial conduits.

Vineberg used the internal thoracic artery (ITA) to achieve indirect myocardial revascularization in 1950, and Green reported direct coronary anastomosis with an operating microscope in 1968. It was not until the early 1980s that superior 10-year patency compared with saphenous vein was established for the ITA. In 1986, Loop proved better patient survival at 10 years when the left ITA was grafted to the left anterior descending artery rather than vein in patients with triple-vessel disease having complete revascularization. Only in 1998 has Lytle shown enhanced survival with use of two ITAs over one in triple-vessel disease. This report came 4 months after a report showing no additional benefit from the second ITA. Increasingly, complex use of arterial conduits allows complete revascularization with two arterial conduits (both ITAs or one ITA and one radial artery) in most patients (with 10-year data soon to be available in the former). The T-graft configuration (ITA T-graft or radial T-graft) is highly complex and utilizes single-source inflow to the entire heart (in addition to native coronary flow), which may not provide adequate inflow and remains controversial. Although patency for the ITA is well established, this cannot be said for the radial artery (one report of 55 conduits to 5.5 years), the gastroepiploic artery (one report of 44 conduits to 7 years), or the inferior epigastric artery (one report of 154 conduits to 43 months). Long-term follow-up of each conduit and each configuration is required to prove its durability and, therefore, value in the operative management of coronary disease.

Total arterial revascularization with an internal thoracic artery and radial artery T graft.

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 <35%) in 12%, and left main stenosis was present in 14%. 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.

Extended use of arterial conduits for myocardial revascularization.

Myocardial revascularization by means of surgical coronary artery bypass grafting has proven to provide reproducible and durable relief from the sequellae of coronary atherosclerosis. Despite the proven success of this operation, efforts are ongoing both to reduce the perioperative risks and morbidity, as well as to improve the long-term outcomes. The use of multiple arterial conduits is an example of the latter. This is based on the proven superior long-term patency of arterial grafts as compared with venous conduits. A remarkable wide variety of conduits and configurations are being explored currently. We outline our current thinking with regard to arterial grafting as the field now stands. The early results are encouraging, and suggest a significant improvement in long-term relief from angina pectoris and freedom from reintervention when multiple arterial conduits are employed.

Arterial grafting: techniques and conduits.

The superior long-term patency and survival of the internal thoracic artery in coronary artery bypass grafting, compared with saphenous vein, established the internal thoracic artery as the conduit of choice for myocardial revascularization. Use of the internal thoracic artery has expanded, and the possibility of similar performance by other arteries has motivated surgeons to investigate alternative arterial conduits (eg, the gastroepiploic artery, inferior epigastric artery, and radial artery). Although these grafts have become more technically feasible and have shown benefits, more follow-up data are needed to determine the long-term patency, freedom from arteriosclerosis, and efficacy of alternative conduits.

Mitral valve replacement: randomized trial of St. Jude and Medtronic Hall prostheses.

BACKGROUND: This study was designed to better define the merits of the bileaflet and tilting-disc valves. METHODS: We prospectively randomized 156 patients (mean age, 59 years) to receive either the St. Jude (n = 80) or the Medtronic Hall (n = 76) mitral valve prosthesis between September 1986 and December 1997. The two groups were not significantly different with respect to preoperative New York Heart Association class, left ventricular ejection fraction, incidence of mitral stenosis or insufficiency, extent of coronary artery disease, completeness of revascularization, or cross-clamp or bypass time. RESULTS: The operative mortality (11.2% versus 13.1%, St. Jude versus Medtronic Hall, respectively) and late mortality (27% versus 22%, St. Jude versus Medtronic Hall, respectively) were not significantly different. Follow-up was complete in all hospital survivors with a mean of 60.7 months (range, 1 to 133 months). The analysis of 10-year actuarial survival and freedom from valve-related events demonstrated no significant differences between the cohorts. Freedom from reoperation was higher in the St. Jude group (p < 0.01). Comparisons of patient functional status and echocardiographic hemodynamic parameters obtained at the time of follow-up demonstrated no significant differences between the two prostheses. CONCLUSIONS: This study suggests that there is no difference between the St. Jude and Medtronic Hall prostheses with respect to late clinical performance or hemodynamic results and therefore does not support the preferential selection of either prosthesis.

Intermittent antegrade tepid versus cold blood cardioplegia in elective myocardial revascularization.

BACKGROUND: The ideal temperature for blood cardioplegia administration remains controversial. METHODS: 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. RESULTS: 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; p < 0.0001). After reperfusion, group T exhibited significantly greater lactate and acid release despite similar levels of oxygen extraction (p < 0.05). The creatine kinase-MB isoenzyme release was significantly lower in group T (764 +/- 89 versus 1,120 +/- 141 U x h/L; p < 0.04). 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 (p < 0.05). The frequency of ventricular defibrillation after cross-clamp removal was lower in this cohort (p < 0.05). There were no hospital deaths, and both groups had similar postoperative courses. CONCLUSIONS: 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.