Coronary artery imaging with multidetector computed tomography: a call for an evidence-based, multidisciplinary approach

Modern multidetector computed tomography systems are capable of a comprehensive assessment of the cardiovascular system, including noninvasive assessment of coronary anatomy. Multidetector computed tomography is expected to advance the role of noninvasive imaging for coronary artery disease, but clinical experience is still limited. Clinical guidelines are necessary to standardize scanner technology and appropriate clinical applications for coronary computed tomographic angiography. Further evaluation of this evolving technology will benefit from cooperation between different medical specialties, imaging scientists, and manufacturers of multidetector computed tomography systems, supporting multidisciplinary teams focused on the diagnosis and treatment of early and advanced stages of coronary artery disease. This cooperation will provide the necessary education, training, and guidelines for physicians and technologists assuring standard of care for their patients.

Tracheostomy after cardiovascular surgery: An assessment of long-term outcome

OBJECTIVE

To ascertain long-term survival, identify risk factors for death, and document complications of tracheostomy after cardiovascular surgery.

METHODS

Between January 1, 1998, and September 1, 2001, 188 (1.4%) of 13,191 patients undergoing cardiovascular surgery had tracheostomy for respiratory failure 5 to 79 days (median, 14 days) after surgery. Factors associated with mortality were identified in the hazard function domain, and mode of death and complications of tracheostomy were determined by follow-up.

RESULTS

Survival was 75%, 50%, and 31% at 30 days, 3 months, and 2 years, respectively. The most important risk factors for death were older age (P = .004) and variables representing deteriorating hemodynamic (P < .0001), respiratory (P < .0001), and renal (P = .0001) function between the index cardiovascular operation and tracheostomy. The mode of death was isolated respiratory failure in only 21 (16%) of 130 patients, but multisystem organ failure in 71 (55%). Follow-up of 58 survivors identified voice complaints in 13 (24%), tracheal stenosis in 5 (9.2%), and permanent tracheostomy in 3 (6%).

CONCLUSIONS

Only one third of patients undergoing tracheostomy after cardiovascular surgery survive, because it is used primarily in those with deteriorating function of multiple organ systems. Although tracheostomy may enhance patient comfort and simplify nursing care, selection algorithms need to be developed if survival is the goal of the intervention.

Does use of a right internal thoracic artery increase deep wound infection and risk after previous use of a left internal thoracic artery?

OBJECTIVE

To determine whether adding right internal thoracic artery to previous left internal thoracic artery bypass at reoperation increases deep sternal wound infection and hospital mortality, particularly in diabetic patients.

METHODS

Reoperations (n = 2875; 2381 men) in patients with previous left internal thoracic artery bypass were performed between January 1990 and January 2003; 1939 (67%) had no repeat internal thoracic artery grafting, 923 (32%) received an additional right internal thoracic artery graft, and 13 (0.5%) had bilateral internal thoracic artery grafting with reuse of the left internal thoracic artery. Of the patients, 352 (12%) were insulin-treated and 590 (21%) non-insulin-treated diabetics. Multivariable logistic regression analysis was used to identify preoperative variables associated with right versus non-right internal thoracic artery use in diabetics and nondiabetics and to formulate propensity models. Propensity scores were used for matching and adjusted multivariable analyses of deep wound infection and hospital mortality.

RESULTS

Deep wound infection occurred in 3.0% (7/230) of diabetics receiving right internal thoracic artery grafts, 2.2% (5/230) of propensity-matched diabetics receiving non-right internal thoracic artery grafts (P = .6), in 1.1% (6/538) of nondiabetics receiving right internal thoracic artery grafts, and in 1.0% (5/538) of matched non-diabetic patients receiving non-right internal thoracic artery grafts (P = .8). Corresponding hospital mortality in these matched groups was 1.7% (4/230) versus 6.1% (14/230) for diabetics (P = .02) and 2.6% (14/538) versus 3.5% (19/538) for nondiabetics (P = .4). Risk factors for deep wound infection included higher weight (P = .0003), higher New York Heart Association functional class (P = .03), and less severe left anterior descending disease (P = .03). Risk factors for death were (P < .02) emergency operation, mitral valve replacement, and greater number of saphenous vein grafts.

CONCLUSIONS

Use of the right internal thoracic artery for reoperations does not increase the risk of deep wound infections in diabetics or nondiabetics and does not increase mortality.

Mitral Valve Surgery in the Adult Marfan Syndrome Patient

BACKGROUND

Because mitral valve dysfunction in adults with Marfan syndrome is poorly characterized, this study compares mitral valve pathophysiology and morphology with that of myxomatous mitral disease, documents types of mitral valve operations, and assesses long-term survival and durability of mitral valve surgery in Marfan patients.

METHODS

From May 1975 to June 2000, 27 adults with Marfan syndrome underwent mitral valve surgery. Their valve pathophysiology and morphology was compared with that of 119 patients with myxomatous mitral disease undergoing surgery from September 1995 to March 1999. Survival and repair durability were assessed at follow-up.

RESULTS

Compared with myxomatous disease patients, Marfan patients had less posterior leaflet prolapse (44% versus 70%, p = 0.01), more bileaflet (44% versus 28%, p = 0.09) and anterior leaflet prolapse (11% versus 3%, p = 0.07), and presented earlier for surgery (age 41 +/- 12 years versus 57 +/- 13, p < 0.0001). Marfan patients had longer and thinner leaflets. Mitral valve repair was performed less frequently in Marfan (16 of 27, 59%) than myxomatous disease patients (112 of 119, 94%). There were no hospital deaths; at 10 years, survival was 80% and freedom from reoperation 96%, with only 1 reoperation among the 16 repairs.

CONCLUSIONS

Mitral valve pathophysiology and morphology differ between Marfan and myxomatous mitral valve diseases. Valve repair in Marfan patients is durable and gives acceptable long-term results, even in adults who present with advanced mitral valve pathology. With increasing use of the modified David reimplantation operation and sparing of the aortic valve, mitral valve repair is a greater imperative, particularly since we have not had to reoperate on any Marfan patients with reimplantations.

The Society of Thoracic Surgeons/American Association for Thoracic Surgery Off-Pump Training Program

BACKGROUND

Opportunities to acquire knowledge and skills in new technology are limited for cardiothoracic surgeons after completion of residency. In 2000 The Society of Thoracic Surgeons/American Association for Thoracic Surgery Joint Committee for New Technology Assessment accepted an educational grant from the Foundation for Advanced Medical Education to implement and test an instructional program for practicing cardiothoracic surgeons in off-pump coronary bypass surgery.

METHODS

Twenty-four surgeons were selected for participation. Instruction was provided in three phases: (1) a preliminary video illustrating the techniques; (2) 2-day training sessions at two separate locations linked by videoconference; and (3) visits by trainees to observe preceptor surgeons at their institutions, followed by visits of preceptor surgeons to the institutions of the trainees. Evaluation of the program was made by review of trainee case lists in the year after completion of the program and by written surveys completed by trainees and preceptors.

RESULTS

Seventeen surgeons completed all phases of the program. Most of them reported frequently utilizing off-pump bypass surgery in practice with good results. Two surgeons dropped out of the program before the first phase, and 5 surgeons did not complete all preceptor visits. Most survey respondents commented that the program met or exceeded their expectations.

CONCLUSIONS

Some trainees were unable to complete proctor visits because of professional responsibilities at home or because of difficulty in advanced scheduling of procedures. More rigorous selection and stronger administrative controls might have reduced program dropouts. The instructional model worked extremely well for properly selected and motivated surgeons.

Influence of patient characteristics and arterial grafts on freedom from coronary reoperation

OBJECTIVE

Arteriosclerosis is a progressive disease, and many patients require repeat coronary intervention after coronary artery bypass grafting. We sought to identify patient characteristics and operative factors that predict the need for or bias toward reoperative coronary artery bypass grafting.

METHODS

From 1971 to 1998, 48,758 patients underwent primary isolated coronary artery bypass grafting, and 1000 per year were followed every 5 years (n = 26,927). A multivariable time-related analysis was performed to model freedom from coronary reoperation and to identify patient and operative variables associated with occurrence of coronary reoperation.

RESULTS

Freedoms from reoperative coronary artery bypass grafting were 99.6%, 98.4%, 93%, 82%, 72%, and 65% at 1, 5, 10, 15, 20, and 25 years, respectively. Risk of reoperation (hazard function) demonstrated a short, rapidly declining early phase, followed by a long, slow-rising late phase. Patient variables that increased the likelihood of coronary reoperation included younger age (P < .0001), higher total cholesterol (P = .0004) and triglyceride levels (P = .0005), lower high-density lipoprotein (P = .0002) level, diabetes mellitus (P < .0001), and more extensive coronary artery disease (P = .01). Increasing extent of arterial grafting performed at primary coronary artery bypass grafting decreased occurrence of coronary reoperation (P < .0001).

CONCLUSION

Patient factors associated with arteriosclerosis progression and type of bypass conduit influence the need for or bias toward repeat coronary artery bypass grafting. Aggressive patient risk-factor reduction and extensive arterial coronary revascularization at primary coronary artery bypass grafting should result in fewer coronary reoperations.

Transfusion increases the risk of postoperative infection after cardiovascular surgery

BACKGROUND

Because of the immunomodulatory effects of transfusion, we attempted to identify factors associated with blood product use and determine the association of transfusion quantity with postoperative infection.

STUDY DESIGN

We studied total perioperative transfusion of blood products for 15,592 cardiovascular operations performed from July 1998 to May 2003. Infection end points were septicemia/bacteremia (n=351, 2.2%) and superficial (n=353, 2.3%) and deep (n=212, 1.4%) sternal wound infections. Factors associated with blood product administration were used to form balancing scores to adjust for differences in patient characteristics among those receiving and not receiving blood products.

RESULTS

Fifty-five percent of patients received packed red blood cells (RBC), 21% received platelets, 13% got fresh frozen plasma (FFP), and 3% got cryoprecipitate. Factors associated with RBC use included older age, female gender, higher New York Heart Association class, lower hematocrit, reoperation, and longer cardiopulmonary bypass time--all indicative of higher-risk patients. The more RBC units transfused, the higher was the occurrence of septicemia/bacteremia (p < 0.0001) and superficial (p=0.0007) and deep (p < 0.0001) sternal wound infection. Use of FFP (septicemia/bacteremia) and platelets (septicemia/bacteremia and deep sternal wound infection) mitigated against this association only slightly.

CONCLUSIONS

Blood products tended to be used in the sickest patients. But after accounting for this, risk of infection increased incrementally with each unit of blood transfused. Although cause and effect cannot be established, results suggested that blood product transfusion is an independent risk factor for postoperative infection in cardiac surgical patients, blood products are more likely to be used in the sickest patients, and no amount of blood loss treated by transfusion is innocuous.

Predictors of revascularization method and long-term outcome of percutaneous coronary intervention or repeat coronary bypass surgery in patients with multivessel coronary disease and previous coronary bypass surgery

AIMS

The optimal revascularization strategy in patients with symptomatic multivessel coronary artery disease (CAD) and previous coronary artery bypass grafting (CABG) remains unknown.

METHODS AND RESULTS

We evaluated all patients with previous CABG undergoing isolated, non-emergency multivessel revascularization between 1 January 1995 and 31 December 2000. The analysis concentrated on the independent predictors of the revascularization method, as well as on long-term mortality and its predictors, after calculating a propensity score for the method of revascularization. There were 2191 patients (1487 with reoperation and 704 with percutaneous coronary intervention, PCI) in the study. The most important factors in choosing reoperation were presence of more diseased or occluded grafts, previous infarction, lower ejection fraction (EF), longer interval from first CABG, and more total occlusions of native arteries, as well as absence of a patent mammary graft. The distribution of the propensity score was skewed towards the two extremes. At 5 years, the unadjusted cumulative survival was 79.5% for CABG and 75.3% for PCI, P=0.008. After adjustment for the propensity score for PCI vs. CABG, PCI was associated with a hazard ratio of 1.47 (0.94-2.28), P=0.09. The most powerful predictors of mortality were higher age and lower EF.

CONCLUSION

The choice of the revascularization method in patients with previous CABG is dictated mostly by anatomical considerations and less by clinical characteristics. In contrast, clinical characteristics predominantly affect long-term outcome, whereas the method of revascularization has a limited effect. A randomized clinical trial addressing this important segment of the population with ischaemic heart disease is warranted.

Is Reoperation Still a Risk Factor in Coronary Artery Bypass Surgery?

BACKGROUND

Hospital mortality for reoperative coronary artery bypass grafting (CABG) is approaching that of primary CABG. This raises two questions: (1) has experience neutralized the risk of reoperation attributable to its greater difficulty, or (2) has experience neutralized the risk attributable to the higher-risk profile of reoperative patients?.

METHODS

From 1990 to 2003, 21,568 CABG procedures were performed, of which 4,518 (21%) were reoperations: 3,919 first, 552 second, 43 third, 3 fourth, and 1 fifth. Reoperative patients had a higher-risk profile than primary patients, with more vascular disease, left ventricular dysfunction, and coronary artery disease (all p < 0.0001). Logistic regression was used to identify factors associated with hospital death and to develop a propensity score for reoperation, which was used to (1) adjust multivariable analyses of death and (2) compare outcomes in matched patients.

RESULTS

Hospital mortality was 4.3% (168 of 3,919) for first reoperation, 5.1% (28 of 552) for second, and 6.4% (3 of 47) for third or more, compared with 1.5% (263 of 17,050) for primary operations. Risk of both primary and reoperative CABG decreased with experience (p > 0.0002); however, reoperative risk fell markedly in the mid-1990s. In both the overall and matched-pairs analyses, reoperation was a risk factor before 1997 (p < or = 0.008), but not after (p = 0.2). Reoperation within 1 year of previous CABG increased risk (p < 0.0001). Risk attributable to left ventricular dysfunction decreased with experience (p = 0.05).

CONCLUSIONS

Hospital mortality for reoperative CABG has been consistently higher than for primary operation, but this difference has narrowed considerably. Patient characteristics, not reoperation itself, now have greater influence.

Evaluation of left ventricular outflow tract area after septal reduction in obstructive hypertrophic cardiomyopathy: a real-time 3-dimensional echocardiographic study

BACKGROUND

The comparative impact of percutaneous alcohol septal reduction (ASR) and surgical myectomy on the left ventricular outflow tract (LVOT) area in patients with obstructive hypertrophic cardiomyopathy (HC) is not well defined. Real-time 3-dimensional echocardiography (RT3DE) provides accurate information about the LVOT geometry and shape. We aimed to analyze the change in LVOT area after septal reduction interventions in patients with obstructive HC using RT3DE.

METHODS

Thirty-one HC patients (mean age 53 +/- 17 years) undergoing ASR (n = 14) or myectomy (n = 17) were studied at baseline and during follow-up with RT3DE. LVOT area was measured after observing the LVOT in the 3D space as the smallest area during midsystole. LVOT pressure gradients were determined by conventional continuous wave Doppler.

RESULTS

Overall, LVOT area increased from 0.86 +/- 0.20 to 2.50 +/- 0.88 cm2 (P < .01), and the resting LVOT pressure gradient decreased from 64 +/- 41 to 16 +/- 10 mm Hg (P < .01) after a median follow-up of 3 months after intervention (range 1-24 months). A similar significant decrease in LVOT pressure gradients was seen in myectomy and ASR groups (from 62 +/- 39 to 12 +/- 5 mm Hg and from 67 +/- 43 to 21 +/- 14 mm Hg, respectively, P < .01 in between each group, and P = NS between both groups). However, the increase in LVOT area was greater in myectomy than in ASR group (from 0.81 +/- 0.22 to 2.90 +/- 0.64 cm2 and 0.93 +/- to 0.16 to 2.02 +/- 0.92 cm2, respectively, P < .01 between both groups).

CONCLUSION

RT3DE demonstrated an effective increase in LVOT area after both ASR and myectomy. This technique may be useful for assessing the results of septal reduction in patients with obstructive HC.

Ischemic Versus Degenerative Mitral Regurgitation: Does Etiology Affect Survival?

BACKGROUND

Ischemic mitral regurgitation (MR) is associated with poor survival and degenerative MR with excellent survival. We hypothesized that in some patients with degenerative MR requiring concomitant coronary artery bypass grafting (CABG), ischemic disease would dominate prognosis, resulting in survival as poor as in patients with ischemic MR. Thus, we (1) determined survival impact of etiology (degenerative vs ischemic) after combined mitral valve repair and CABG and (2) explored survival differences within etiology groups.

METHODS

From 1985 to 2003, 710 patients underwent mitral valve repair for degenerative MR and concomitant CABG (two diseases); 400 patients had mitral annuloplasty and CABG for functional ischemic MR (one disease). Patients were propensity-matched on demography, symptoms, comorbidities, coronary artery disease, and left ventricular function. Survival was compared between matched groups and within groups.

RESULTS

Compared with patients with degenerative MR, those with ischemic MR had more extensive coronary artery disease, worse ventricular function, more comorbidities, and more symptoms (p < 0.05). Unadjusted 5-year survivals were 64% and 82% for patients with ischemic and degenerative MR, respectively. However, 123 ischemic and degenerative MR matched pairs had equivalently poor 5-year survival (p > 0.9), 66% and 65%, respectively. Among patients with degenerative MR, survival varied widely, depending largely on ischemic burden and extent of left ventricular dysfunction.

CONCLUSIONS

The large survival discrepancy between patients with ischemic and degenerative MR is attributable to differences in patient profile, particularly extent of ischemic disease and left ventricular dysfunction. Thus, ischemic and degenerative MR patients with equivalent characteristics have equivalently poor survival.

The effect of bilateral internal thoracic artery grafting on survival during 20 postoperative years

BACKGROUND

To compare survival of patients receiving bilateral internal thoracic artery grafts and single internal thoracic artery grafts more than 20 postoperative years, assess magnitude of benefit, and identify predictors of benefit.

METHODS

From cohorts of 8123 patients receiving single internal thoracic artery grafts and 2001 receiving bilateral internal thoracic artery grafts during primary isolated bypass operations for multivessel coronary disease between 1971 and 1989, we identified 1152 propensity-matched pairs. Mean follow-up of survivors was 16.5 years, with 51 patients followed for 20 years or more. Hazard function methodology was used to identify risk factors for mortality, compare survival, and assess magnitude of benefit.

RESULTS

Comparison of the matched pairs showed survival of the bilateral internal thoracic artery and single internal thoracic artery groups at 7, 10, 15, and 20 years was 89% versus 87%, 81% versus 78%, 67% versus 58%, and 50% versus 37%, respectively (p < 0.0001). Divergence of bilateral internal thoracic artery and single internal thoracic artery hazard function curves continued to widen through 20 postoperative years. At 20 years, bilateral internal thoracic artery grafting was predicted to produce worse survival in 2.8% of patients, a survival advantage of less than 5% in 12.9%, greater than 10% in 52%, and greater than 15% in 7.6%. Combinations of cardiac and noncardiac descriptors were used to define higher and lower risk patient subsets. Advanced age, abnormal left ventricular function and noncardiac risk factors decreased overall survival but the incremental benefit of bilateral internal thoracic artery grafting persisted.

CONCLUSIONS

Bilateral internal thoracic artery grafting produces improved survival compared with single internal thoracic artery grafting during the second postoperative decade, and the magnitude of that benefit increases through 20 postoperative years.

Does the arterial cannulation site for circulatory arrest influence stroke risk?

BACKGROUND

We investigated whether axillary/subclavian artery inflow with a side graft decreases the risk of stroke versus cannulation at other sites during hypothermic circulatory arrest.

METHODS

Between January 1993 and May 2003, 1,352 operations with circulatory arrest were performed for complex adult cardiac problems. A single arterial inflow cannulation site was used in 1,336 operations, and these formed the basis for comparative analyses. Cannulation sites were axillary plus graft in 299 operations, direct cannulation of the aorta in 471, femoral in 375, innominate in 24, and axillary or subclavian without a side graft in 167. Retrograde brain perfusion was used in 933 (69%). A total of 272 (20%) were for emergencies, 432 (32%) were reoperations, and 439 (32%) were for dissections. A total of 617 (46%) had aortic valve replacement and 1,160 (87%) ascending, 415 arch (31%), and 248 descending (18%) aortic replacements. Indications also included arteriosclerosis (n = 301) and calcified aorta (n = 278). Primary comparisons were made by using propensity matching, and, secondarily, risk factors for stroke or hospital mortality were identified by multivariable logistic regression.

RESULTS

Stroke occurred in 6.1% of patients (81/1,336): 4.0% (12/299) of those had axillary plus graft and 6.7% who had direct cannulation (69/1,037; p = 0.09; p = 0.05 among propensity-matched pairs). Operative variables associated with stroke included direct aortic cannulation, aortic arteriosclerosis, descending aorta repair, and mitral valve replacement. The risk of hospital mortality was higher (11%; 42/375) for patients who had femoral cannulation than axillary plus graft (7.0%; 21/299; p = 0.06; p = 0.02 among propensity-matched pairs).

CONCLUSIONS

Axillary inflow plus graft reduces stroke and is our method of choice for complex cardiac and cardioaortic operations that necessitate circulatory arrest. Retrograde or antegrade perfusion is used selectively.

Comparing On-Pump and Off-Pump Coronary Artery Bypass Grafting

One of the most hotly debated and polarizing issues in cardiac surgery has been whether coronary artery bypass grafting (CABG) without the use of cardiopulmonary bypass or cardioplegia (off-pump CABG, or OPCAB) is superior to that performed with the heart-lung machine and the heart’s being chemically arrested (standard CABG). Various clinical trials are reviewed comparing the 2 surgical strategies, including several large retrospective analyses, meta-analyses, and the randomized trials that address different aspects of standard CABG and OPCAB. Although definitive conclusions about the relative merits of standard CABG and OPCAB are difficult to reach from these varied randomized and nonrandomized studies, several generalizations may be possible. Patients may achieve an excellent outcome with either type of procedure, and individuals’ outcomes likely depend more on factors other than whether they underwent standard CABG or OPCAB. Nevertheless, there appear to be trends in most studies. These trends include less blood loss and need for transfusion after OPCAB, less myocardial enzyme release after OPCAB up to 24 hours, less early neurocognitive dysfunction after OPCAB, and less renal insufficiency after OPCAB. Fewer grafts tend to be performed with OPCAB than with standard CABG. Length of hospital stay, mortality rate, and long-term neurological function and cardiac outcome appear to be similar in the 2 groups. To definitively answer the remaining questions of whether either strategy is superior and in which patients, a large-scale prospective randomized trial is required.

Comparison of Saphenous Vein and Internal Thoracic Artery Graft Patency by Coronary System

BACKGROUND

We sought to compare saphenous vein and internal thoracic artery graft patency by coronary system.

METHODS

From 1972 to 1999, 50,278 patients underwent primary coronary surgery; subsequently, 4,333 had angiography of 2,121 internal thoracic artery and 8,733 saphenous vein grafts. Longitudinal analysis was used to model graft occlusion and identify risk factors. Using the model, patency was calculated twice for each graft and compared first as if an internal thoracic artery, and second as if a saphenous vein, were used.

RESULTS

Unadjusted 1-, 5-, and 10-year patency was 93%, 88%, and 90% for internal thoracic arteries and 78%, 65%, and 57% for saphenous veins. At 10 years, internal thoracic arteries were more likely than saphenous veins to be patent to left anterior descending in 99.1% of cases, to diagonals in 98.3%, to circumflex in 98.3%, to posterior descending artery in 98.5%, and to right coronary arteries in 82.5%. For right coronary arteries, saphenous vein patency was equivalent to or better than internal thoracic artery patency early after surgery. However, by 10 years, internal thoracic artery patency was better in right coronary arteries with 70% stenosis or greater. At all times after surgery and all levels of clinically important coronary stenosis, internal thoracic artery patency surpassed saphenous vein patency in grafts to the left anterior descending, diagonal, circumflex, and posterior descending arteries.

CONCLUSIONS

Internal thoracic arteries demonstrate better patency than saphenous veins except when grafting moderately stenosed right coronary arteries. When bypassing right coronary arteries with less than 70% stenosis, saphenous veins may be a better choice.

Recurrent mitral regurgitation after annuloplasty for functional ischemic mitral regurgitation

OBJECTIVES

We sought to characterize the temporal return of mitral regurgitation after annuloplasty for functional ischemic mitral regurgitation; to identify its predictors, particularly with respect to annuloplasty type; and to determine whether annuloplasty type influences survival.

METHODS

From April 1985 through November 2002, 585 patients underwent annuloplasty alone for repair of functional ischemic mitral regurgitation, generally with concomitant coronary revascularization (95%). A flexible band (Cosgrove) was used in 68%, a rigid ring (Carpentier) in 21%, and bovine pericardial annuloplasty (Peri-Guard) in 11%. Six hundred seventy-eight postoperative echocardiograms were available in 422 patients to assess the time course of postoperative mitral regurgitation and its correlates. Most echocardiograms were performed early after the operation (median, 8 days); 17% were performed at 1 year or beyond.

RESULTS

During the first 6 months after repair, the proportion of patients with 0 or 1+ mitral regurgitation decreased from 71% to 41%, whereas the proportion with 3+ or 4+ regurgitation increased from 13% to 28% ( P < .0001); the regurgitation grade was stable thereafter. The temporal pattern of development of 3+ or 4+ regurgitation was similar for Cosgrove bands and Carpentier rings (25%) but substantially worse for Peri-Guard annuloplasties (66%). Small annuloplasty size did not influence postoperative regurgitation grade ( P = .2), although Cosgrove bands were used in most patients receiving 26- and 28-mm annuloplasties. Freedom from reoperation was 97% at 5 years. Annuloplasty type was not associated with survival.

CONCLUSIONS

Although initial mitral valve replacement would eliminate the risk of postoperative mitral regurgitation, this strategy has been associated with reduced survival. Therefore the development of additional techniques is necessary to achieve more secure repair of functional ischemic mitral regurgitation.

Aortic Dissection After Previous Cardiovascular Surgery

BACKGROUND

Risk of repairing aortic dissection after previous cardiovascular surgery has not been described clearly. This study assesses early and late outcomes of such reoperations.

METHODS

From January 1, 1990, to January 1, 2002, 108 patients with prior cardiovascular surgery (isolated coronary artery bypass grafting, 51%; isolated valve surgery, 21%; aortic aneurysm repair, 24%; and combinations of these in the remainder) underwent reoperation for aortic dissection (emergency operation for acute dissection in 24%). Mean age was 63 +/- 13 years, and 85% were men. The interval since prior surgery ranged from 10 days to 22 years (median, 3.8 years). This was the third operation for 8%. Ascending aortic repair with or without aortic arch or descending aortic repair was performed in 40%, aortic valve replacement (n = 15) or repair (n = 17) with ascending aortic repair in 30%, aortic root replacement with or without aortic arch or descending aortic repair in 30%, and aortic arch with or without descending aortic repair in 1%. Circulatory arrest was used in 78%, with retrograde brain perfusion in 58%.

RESULTS

Hospital mortality was 6%, stroke 4%, renal failure 2%, and respiratory failure 7%. Survival at 30 days and 1, 3, 5, and 7 years was 93%, 85%, 74%, 63%, and 53%, respectively. Aortic reoperation was performed in 7 patients, with freedom from this event at 30 days and 1, 3, 5, and 7 years of 98%, 95%, 93%, 91%, and 89%., respectively

CONCLUSIONS

Aortic dissection after cardiovascular surgery is rare and can be managed with acceptable operative risks and good long-term survival. Need for subsequent aortic reoperation is uncommon.