Mitral valve surgery after previous CABG with functioning IMA grafts

Background. Mitral valve surgery after previous coronary artery bypass grafting presents a challenging problem for the cardiac surgeon. An injury to patent coronary artery bypass grafts, especially internal mammary artery grafts, during reoperation via a redo sternotomy, may be fatal. Therefore, a reliable alternative to the redo sternotomy is desirable to minimize potential injury to internal mammary artery grafts.

Methods. Between February 1987 and October 1998, we performed 59 consecutive mitral valve operations after previous coronary artery bypass grafting surgery (CABG). A total of 24 patients (41%) had functioning internal mammary artery (IMA) grafts and represent the population for this study. No patients were excluded for any reason. Of the 24 patients, 20 (83%) were men. Mean age was 66 ± 13 years (range 41 to 83 years) and the mean duration from CABG was 5.3 ± 3.6 years (range 0.1 to 12 years). Four (17%) had functioning bilateral internal mammary artery grafts. All had 3 to 4+ mitral regurgitation (MR) at the time of mitral valve surgery and the mean preoperative ejection fraction (EF) was 40% ± 14% (range 20% to 74 %).

Results. Twenty-one (88%) patients underwent mitral valve surgery through an anterolateral right thoracotomy and 3 (12%) through a redo sternotomy. Twenty-two (92%) patients, including the 3 patients in whom a redo sternotomy was used, had cannulation of the femoral artery and vein. Two patients required axillary artery cannulation. All 21 patients in whom the mitral valve was approached through a right thoracotomy underwent deep hypothermia (19.6° ± 2.1°C, range 14° to 25°C) without aortic clamping, with a mean duration of CPB of 138 ± 46 minutes (range 65 to 249 minutes). In 18 (75%), the MR was ischemic in origin and in 6 (25%) there was myxomatous degeneration. Nine (34%) required valve replacement and 15 (66%) underwent repair. There were no operative or hospital deaths and all patients were discharged to home or to a rehabilitation facility. There were 4 (17%) major complications. Two patients suffered respiratory failure requiring tracheotomy, 1 patient developed a perioperative MI requiring an intraaortic balloon pump and 1 developed heart block requiring a permanent pacemaker. There were no neurologic, peripheral vascular, bleeding, or wound complications.

Conclusions. Reoperative mitral valve surgery in the setting of functioning IMA grafts, even in the face of depressed LV function, can be done safely and with minimal morbidity.     

Mitral valve replacement through right thoracotomy after previous coronary artery bypass grafting

The Usefulness of Brachial Artery Cannulation, Perfused Ventricular Fibrillation with Moderate Hypothermia, and Minimal Dissection Techniques It has been reported by several authors that a right thoracotomy for mitral valve surgery can be useful after previous coronary aortery bypass grafting (CABG). A 76-year-old man with mitral valve regurgitation after previous CABG underwent mitral valve replacement with some modified techniques. Cardiopulmonary bypass was established with right brachial artery cannulation and right femoral venous cannulation with the aid of vacuum-assisted venous drainage. Ventricular fibrillation (VF) was induced by rapid pacing of the ventricle, and mitral valve replacement was performed under perfused VF with moderate hypothermia. The patient’s postoperative course was uneventful. This method appears to be a safe and easy alternative mitral valve surgery for complicated cases of this type.     

Revival of the radial artery for coronary artery bypass grafting.

Eighteen years after its first introduction for coronary artery revascularization, the radial artery (RA) was reinvestigated because of unexpected good long-term results in the early series. Since July 1989, 104 patients underwent myocardial revascularization using 122 RA grafts (18 patients received two grafts). The left internal mammary artery (IMA) was concomitantly used as a pedicled graft in 100 cases and the right IMA in 19 cases; a free IMA graft was used in 29 cases and a saphenous vein graft in 24 cases. A mean of 2.8 grafts per patient were performed. Nine patients underwent associated procedures: carotid endarterectomy (3), aortic valve replacement (3), Bigelow procedure (1), and mitral valve repair (2). The target artery receiving the RA was the circumflex (n = 59), diagonal (n = 29), right coronary (n = 27), and left anterior descending (n = 7). One patient died (0.96%) and 2 had perioperative myocardial infarct. Sternal wound infection was noted in 3 cases of double IMA implantation. No ischemia of the hand was observed. All patients received diltiazem started intraoperatively and continued after discharge. In addition aspirin (100 mg/day) was given at discharge. Early angiographic controls (less than 2 weeks) were obtained in the first 50 consecutive patients and revealed 56 of 56 patent RA grafts, 48 of 48 patent left IMA grafts, 11 of 11 patent right IMA grafts, 14 of 18 patent free IMA grafts, and 8 of 9 patent vein grafts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Crossed double internal mammary-to-coronary artery grafts.

Crossed double internal mammary (IMA)-coronary artery grafts (the left to the left anterior descending artery [LAD], the right to a diagonal or marginal coronary branch) were used without mortality and with excellent functional results in 36 patients requiring separate grafts to these vessels (22% of patients undergoing coronary revascularization). Flows were 70 +/- 9 ml/min in the left and 50 +/- 7 ml/min in the right IMA, respectively. All revisualized grafts remained patient. The location and direction of the LAD and of diagonal and marginal branches allow excellent alignment of these shorter and wider double IMA grafts. The left IMA is the graft of choice for the LAD, and the right IMA is the choice for a high diagonal or early arising marginal branch that requires an additional separate graft. The right IMA is not satisfactory for right coronary or LAD bypass.     

Minimally invasive approach for redo mitral valve surgery: a true benefit for the patient

OBJECTIVES: Redo mitral valve surgery via sternotomy is associated with a substantial morbidity and mortality. This study evaluated a minimally invasive technique for mitral valve redo procedures. MATERIAL AND METHODS: Out of a series of 394 patients undergoing mitral valve repair or replacement via a right minithoracotomy, 39 patients underwent redo mitral valve surgery (59+/-13 years, 23 female). Previous cardiac surgeries included 17 patients with mitral valve repair, 6 patients with mitral valve replacement, 3 patients with aortic valve replacement, 2 patients with atrial septal defect closure, and 11 patients with coronary artery bypass grafting (CABG). In all cases, femoro-femoral cannulation was performed. The port access technique was applied in patients undergoing redo valve surgery. In patients with prior CABG, the operation was performed using deep hypothermia and ventricular fibrillation. RESULTS: In all cases, sternotomy was avoided. The mitral valve was replaced in 20 patients and repaired in 19. Time of surgery and cross-clamp time were comparable with the overall series (168+/-73 [redo] vs 168+/-58 min and 52+/-21 [redo] vs 58+/-25 min). Mortality was 5.1%. One patient had transient hemiplegia due to the migration of the endoclamp. All other patients had uneventful outcomes and normal mitral valve function at 3-month's follow-up. CONCLUSION: Redo mitral valve surgery can be performed safely using a minimally invasive approach in patients with a previous sternotomy. The right lateral minithoracotomy offers excellent exposure. It minimizes the need for cardiac dissection, and thus, the risk for injury. Avoiding a resternotomy increases patient comfort of redo mitral valve surgery.     

Internal mammary artery grafts: technical factors influencing patency

Eight hundred fourteen patients with internal mammary artery (IMA) coronary artery bypass grafts have been restudied 961 times with coronary arteriography, primarily to evaluate the patency of the grafts in the setting of symptomatic coronary occlusive disease. Their records were reviewed to assess graft patency as related to the technical aspects of coronary artery bypass surgery. Patency was evaluated using life-table analysis of the data. The method of harvesting the IMA played no role in patency. The left anterior descending coronary artery was the recipient coronary artery with the highest patency rate. The left IMA had a significantly higher patency rate than the right IMA. As a group, the IMAs had a significantly higher patency rate than saphenous vein grafts. However, there was no difference between right IMA grafts and saphenous vein grafts. The mammary artery grafts that remained patent throughout the study had a significantly higher blood flow after bypass than did those that became occluded (43.0 +/- 0.9 versus 28.9 +/- 1.8 ml/min; p less than .001).     

Inverted L-shape sternotomy as a minimally invasive approach

We report a successful treatment of the complete papillary muscle rupture occurring 16 months after coronary artery bypass grafting (CABG). A 57-year-old man was admitted for the sudden onset of chest pain and cardiogenic shock. Emergency cardiac catheterization revealed severe mitral regurgitation and total occlusion in the right coronary artery, which was successfully revascularized by percutaneous coronary intervention under intra-aortic balloon pumping. The right internal thoracic artery grafted to the left anterior descending artery in the previous CABG was functioning well. An echocardiogram distinctly indicated the ruptured head of the papillary muscle. Since an emergency operation revealed complete rupture of the posterior papillary muscle, mitral valve replacement was carried out through an inverted L-shape sternotomy with T-shape left atriotomy. Our case indicates that the inverted L-shape sternotomy was a useful approach to preserve the function of grafts, and that T-shape left atriotomy offered a good exposure of the mitral valve in the limited surgical field.     

An approach to mitral valve surgery by a T-shaped mini-sternotomy with functioning bilateral internal thoracic artery grafts

We herein report successful surgical treatment of mitral valve regurgitation in a 49-year-old man. He was admitted to our hospital due to acute aggravation of dyspnea on effort. He had a surgical history of coronary artery bypass grafting with bilateral internal thoracic artery grafts. A transthoracic echocardiogram showed severely decreased cardiac function and severe mitral regurgitation due to anterolateral mitral valve leaflet prolapse. Computed tomography showed the right internal thoracic artery running over the front of the aorta to the left circumflex artery. To avoid injury to the functioning grafts during median sternotomy, we chose to perform an inferior T-shaped mini-sternotomy. The surgical field was sufficient to perform mitral valve replacement with a mechanical prosthetic valve under fibrillatory arrest. The grafts were neither dissected nor clamped, and access to the aorta and mitral valve was excellent.     

Mitral valve replacement through right thoracotomy after coronary arterial bypass grafting with functioning conduits.

A 67-year-old man who had undergone coronary artery bypass grafting 3 years previously suffered from severe mitral regurgitation associated with Streptococcal infective endocarditis. He was placed in New York Heart Association functional class III. Preoperative angiography demonstrated good opacification of all 3 conduits implanted in the previous operation. We replaced the mitral valve through an anterolateral right thoracotomy, approaching the mitral valve as an alternative to redoing sternotomy to minimize potential injury to patent grafts. His postoperative course was uneventful. After a 1-month course of antibiotics, the patient was discharged as New York Heart Association class II and at present, 3 months after discharge, is doing well. This approach is an effective alternative to redoing sternotomy for mitral valve operation, especially in patients undergoing a previous coronary arterial bypass grafting via median sternotomy.     

The micro-mitral operation comparing the Port-Access technique and the transthoracic clamp technique

BACKGROUND: Several minimally invasive approaches to the mitral valve have been described, including parasternal incision and right anterolateral thoracotomy. MATERIAL AND METHODS: Since September 1996, 58 patients underwent minimally invasive mitral valve surgery at our institution through a right anterolateral minithoractomy. Two different techniques were used for institution of cardiopulmonary bypass (CPB) and aortic clamping: in the Port-Access group (group A) patients had femoro-femoral cannulation with a special arterial cannula to introduce an endoaortic balloon clamp (n = 23). The second group (group B) of patients underwent femoro-femoral CPB as well in combination with a specially designed transthoracic aortic clamp (Chitwood technique, n = 35). Patients were assigned to either technique in a nonrandomized fashion. Demographics were similar in both groups. RESULTS: In group A, 4 valves were replaced, 19 patients had mitral valve repair. In group B, 7 patients had valve replacement and 28 patients underwent mitral repair. Four patients in group A were converted to Chitwood technique due to endoclamp dysfunction. Operating time, CPB time, cross-clamp time, and postoperative blood loss were lower in group B (operating time 295 +/- 83 min vs. 236 +/- 63.9 min; CPB min 167.6 = 64.9 min vs. 137.6 +/- 38.2 min; cross-clamp time 105.9 +/- 51.7 min vs. 78.9 +/- 25.2 min; postoperative blood loss 584 +/- 428 mL vs. 323 +/- 209 mL [p < 0.05]). Clinical outcome regarding postoperative mechanical ventilatilation time, hospital stay and hospital mortality was not different between groups. CONCLUSIONS: Minimally invasive mitral valve procedures via right anterolateral minithoracotomy, including complex valve repair, can be performed successfully using either technique. However, the Chitwood technique provides better intraoperative handling with shorter operation time and less postoperative blood loss. Additionally, costs of a procedure are less using the Chitwood technique compared to the Port-Access technique.     

Mitral valve replacement after previous coronary artrey bypass grafting( CABG) with functioning left internal thoracic artery( LITA) grafts in an elderly patient; report of a case

An 85-year-old woman had a history of coronary artery bypass grafting (CABG) performed 7 years ago, and dyspnea on effort had been worsening recently. Since echocardiography showed severe mitral valve regurgitation( MR), mitral valve repair was suggested. Preoperative enhanced computed tomography (CT) showed the patent functioning left internal thoracic artery (LITA) graft. Mitral valve replacement (MVR) using a 25 mm CEP bioprosthesis was performed successfully via resternotomy without any intraoperative injury of the heart. Myocardial protection without clamping of functioning LITA was done by both antegrade and retrograde continuous coronary perfusion (RCCP) under mild hypothermia. The postoperative clinical course was uneventful without any hemodynamic compromise. She was discharged on postoperative day 21 without any cardiac events following early introduction of cardiac rehabilitation. From these results, mitral valve reoperation by RCCP under mild hypothermia without control of functioning internal thoracic artery( ITA) grafts could be a safe option in some cases.     

Anterolateral thoracotomy as an alternative to repeat median sternotomy for replacement of the mitral valve

Median sternotomy is the most common approach for repeat cardiac surgery despite the potential complications of cardiac injury. Right anterolateral thoracotomy has been recommended as an alternative for patients undergoing mitral valve replacement, but data supporting one approach over the other do not exist. To compare these procedures, the records of 43 patients who had had a previous median sternotomy and who underwent mitral valve replacement were reviewed. No statistically significant differences between patients undergoing repeat median sternotomy (33 patients) and those undergoing right anterolateral thoracotomy (10 patients) were demonstrable when compared for age, gender, New York Heart Association Functional Class, other diseased valves, urgency of operation, indication for operation, type of valve removed, type of valve implanted, length of postoperative hospitalization, length of operation, days of ventilatory support, length of intensive care unit stay, and survival (90% for thoracotomy group; 76% for median sternotomy group; p, NS). Significant differences between the two groups, favoring right anterolateral thoracotomy, were apparent when comparisons were made for length of perfusion (means, 94.8 min, thoracotomy group; 121.4 min, sternotomy group; p = .03), incidence of reexploration (0%, thoracotomy group; 13%, sternotomy group; p = .001), and blood transfusion (means, 5.3 units, thoracotomy group; 11.4 units, sternotomy group; p = .003). Right anterolateral thoracotomy is an effective alternative to repeat median sternotomy for replacement of the mitral valve in patients who have had a previous median sternotomy.     

70岁以上冠状动脉旁路移植术病人乳内动脉流量测量分析

目的 分析70岁以上冠状动脉旁路移植术病人乳内动脉旁路血管血流量的特点.方法 对2003年1月至2007年1月间78例70岁以上(含70岁)应用乳内动脉非体外循环冠状动脉旁路移植手术(OPCAB)的病人,使用瞬时超声血流测量技术对其乳内动脉平均血流量、搏动指数等指标进行测量并分析.结果 78例病人83根乳内动脉旁路血管平均流量(36.0±21.5)ml/min,平均搏动指数3.50±1.76,血流波形均以舒张期为主.男女性别比、平均流量和搏动指数差异无统计学意义[(39.0±23.1) ml/min对(28.0±14.7) ml/min;(3.30±1.50)对(4.10±2.22),P>0.05],但女病人平均流量较男病人偏低,搏动指数较男病人偏高.结论 70岁以上病人冠状动脉旁路移植术应用乳内动脉是安全、有效的;对老年病人乳内动脉流量的评价分析应当结合老年病人的病变特点.     

Clinical experience in thoracoscopic left internal mammary artery harvesting with voice activated robotic assistance]

Between September 1998 to February 2000, 45 consecutive patients underwent robotic-assisted, video-enhanced coronary artery bypass grafting. All IMA's were harvested using the voice-activated robotic assistant (AESOP 3000, Computer Motion Inc, Santa Barbara, CA) and the Harmonic scalpel (Ethicon Endo-Surgery, Cincinnati, OH). Left IMA's were successfully harvested in all patients. Harvested IMA's were anastomosed to LAD's under direct vision through limited left anterior thoracotomy. The IMA harvest time was 57.8 +/- 23.2 min, intraoperative graft flow was 34.3 +/- 20.5 ml/min, postoperative hospital stay was 3.9 +/- 1.5 days. The early postoperative angiogram showed that all grafts were patent. There was no mortality, no significant morbidity. The robotic assisted, video enhanced CABG provides safe and complete LIMA dissection with minimal manipulation and assures sufficient LITA length for tension free anastomosis.     

Mitral valve replacement through right thoracotomy after coronary arterial bypass grafting with functioning conduits

A 67-year-old man who had undergone coronary artery bypass grafting 3 years previously suffered from severe mitral regurgitation associated withStreptococcal infective endocarditis. He was placed in New York Heart Association functional class III. Preoperative angiography demonstrated good opacification of all 3 conduits implanted in the previous operation. We replaced the mitral valve through an anterolateral right thoracotomy, approaching the mitral valve as an alternative to redoing sternotomy to minimize potential injury to patent grafts. His postoperative course was uneventful. After a 1-month course of antibiotics, the patient was discharged as New York Heart Association class II and at present, 3 months after discharge, is doing well. This approach is an effective alternative to redoing sternotomy for mitral valve operation, especially in patients undergoing a previous coronary arterial bypass grafting via median sternotomy.     

Nonreversed saphenous vein grafts for coronary artery bypass grafting

Between August 1985 and December 1988, valvotomized saphenous vein grafts were used in 365 patients undergoing coronary artery bypass grafting (CABG). In this operation, the femoral end of the vein is attached to the aorta and the pedal end is attached to the coronary artery. Vein diameters measured 8 +/- 2 mm at the femoral end, 4.5 +/- 1.2 mm at the knee level, and 3.5 +/- 1.3 mm at the ankle. Ratios between levels were as follows: knee to femoral end, 0.56, and ankle to femoral end, 0.43. The ratio of knee to femoral end was 0.42 in cases with vein midthigh bifurcation. There were 1,310 grafts implanted (3.6 per patient). In 341 patients, CABG alone was performed, and 24 patients had combined procedures: 11 had CABG with mitral valve replacement, 9 had CABG with aortic valve replacement, 2 had CABG with repair of postinfarct ventricular septal defect, and 2 had CABG with automatic defibrillator implantation. Follow-up (up to 3.5 years) was attained in 97% of patients. For various reasons, 34 patients had a second angiogram between 3 and 41 months postoperatively. Of 120 vein grafts, 108 (90%) were patent. At autopsy, 11 patients with 45 vein grafts had 43 patent and clean grafts and two thrombosed. Use of nonreversed saphenous vein for coronary bypass is recommended. It assures a large proximal anastomosis, natural vein bifurcations can be used with fewer proximal anastomoses, better vein-coronary artery size matching is obtained, and the patency rate is satisfactory.     

Prostacyclin production by internal mammary artery as a factor in coronary artery bypass grafts

Long-term patency of coronary artery bypass grafts (CABG) with internal mammary artery (IMA) is better than with saphenous vein (SV) grafts. To determine if vascular prostacyclin (PGI2) produced by IMA might contribute to the improved outcome, we compared PGI2 generated by IMA and SV fragments from 26 patients undergoing CABG and tested the effect of preoperative, long-term ingestion of of aspirin. Fresh tissues were incubated in buffer +/- 25 mumol/L of sodium arachidonate at 37 degrees C for 5 minutes to stimulate PGI2 production, measured by radioimmunoassay of its major hydrolytic product, 6-keto-PGF1 alpha. Results were expressed in picograms of 6-keto-PGF1 alpha per milligram tissue wet weight for total PGI2 production by vascular segments and picograms per cm2 surface area for endothelial PGI2 production. Endothelial PGI2 production was compared for IMA and SV in template-stirring chambers that exposed only the luminal surface of the vessel, excluding underlying smooth muscle. Endothelial PGI2 production by IMA was significantly higher than production by SV under both basal (mechanical stimulation only 1436 +/- 224 versus 842 +/- 227 pg/cm2, mean +/- SEM, p greater than 0.05) and stimulated (25 mumol/L sodium arachidonate: 3343 +/- 347 versus 2032 +/- 465 pg/cm2, p less than 0.025) conditions in patients not receiving aspirin. For patients receiving aspirin, endothelial PGI2 production by IMA was significantly higher than production by SV in stimulated conditions (1382 +/- 526 versus 683 +/- 124 pg/cm2, p less than 0.05). Histologic examination of the tissue segments revealed intact endothelium after incubation in both IMA and SV. Thus a high capacity for PGI2 synthesis and diminished inhibition of PGI2 after aspirin were demonstrated for IMA compared with SV tissue and may be a factor in the improved patency of IMA grafts.     

Combining off pump coronary artery bypass with mitral valve replacement

Background Conventional approach to combined coronary artery bypass grafting (CABG) and mitral valve replacement (MVR) is associated with longer cardiopulmonary bypass (CPB) and aortic cross clamp (ACC) time leading to high operative risk. Methods We conducted a retrospective review of nine consecutive patients undergoing coronary artery bypass grafting/mitral valve replacement combining the off pump technique with cardioplegic arrest. Elective intra aortic balloon pump (IABP) support was instituted in all cases. CABG was first done in all cases without cardiopulmonary bypass support. Mitral valve replacement was then done using conventional cardiopulmonary bypass and cardioplegic arrest using the superior septal approach. Results Nine consecutive patients underwent coronary artery bypass grafting with mitral valve replacement including three patients with acute myocardial infarction. Preoperative echocardiogram revealed a mean ejection fraction (EF) of 38.4 ± 6.0%. Intra aortic balloon pump was inserted in all patients preoperatively. The average number of grafts were 3.0 ± 0.7. Eight patients received bioprosthetic valve while one patient received mechanical prosthesis. The average length of stay in intensive care unit was 3.3 ± 0.5 days. There was no mortality. One patient had superficial wound infection. Conclusion The data suggest that the combined technique (off pump coronary artery bypass grafting and conventional mitral valve replacement) is a safe method to perform coronary artery bypass grafting/mitral valve replacement with minimal morbidity and mortality.     

Aortic valve surgery after previous coronary artery bypass grafting with functioning internal mammary artery grafts

BACKGROUND: Aortic valve surgery after coronary artery bypass grafting (CABG) in the setting of patent pedicled internal mammary artery (IMA) grafts poses a high risk because of the underlying ischemic and valve disease. Unlike mitral valve surgery or CABG, in which aortic clamping (AoX) may be optional, aortic valve surgery uniformly requires AoX unless circulatory arrest is used. Management of the IMA graft in these circumstances has traditionally involved dissection and clamping to prevent regional myocardial warming and cardioplegia "washout" during AoX. An alternative strategy involves avoiding dissection of the IMA, leaving the IMA graft open and establishing moderate-to-deep hypothermia during AoX and cardioplegic arrest. To date, no study has been published documenting the safety and efficacy of the latter practice. METHODS: A total of 94 patients who had patent IMA graft and underwent aortic valve surgery under AoX and cardioplegia between April 1992 and March 2001 were analyzed. The IMA was avoided and left open during AoX, and the patients were cooled systemically (median 20 degrees C). Patients ranged in age from 55 to 90 years (median 73.5 years). Ejection fraction was 15% to 83% (median 50%). Of the patients, 18 (19%) underwent minimally invasive upper hemi-resternotomy. Analysis for predictors of outcome was performed. RESULTS: The operative mortality, perioperative myocardial infarction (MI), and stroke rates were 6.4%, 7%, and 11%, respectively. No significant independent predictors of operative mortality or MI could be identified in the multivariate analysis, although a trend was shown for operative mortality with urgent procedures and patients requiring concomitant surgery of the ascending or arch aorta or aortic root. Advanced age and prolonged cardiopulmonary bypass predicted stroke in the multivariate analysis. There were five (5%) IMA injuries, all occurring during reentry or mediastinal dissection, but none in the subgroup of patients who underwent minimally invasive procedures. All patients survived. CONCLUSIONS: Patients undergoing aortic valve surgery after CABG in the presence of patent IMA represent a potentially high-risk group. Because AoX is almost uniformly required, a decision regarding the management of the IMA pedicle is needed. We have found that leaving the IMA undissected and unclamped is a reasonable strategy, provided that systemic cooling for myocardial protection is established to prevent regional warming and to compensate for cardioplegia washout effect during AoX.     

Efficacy of the internal mammary artery in combined aortic valve replacement-coronary artery bypass grafting

BACKGROUND: While internal mammary artery (IMA) use predicts improved survival after coronary bypass grafting (CABG), it remains unknown whether patients undergoing concomitant aortic valve replacement (AVR) realize a similar benefit. METHODS: All patients at a single teaching institution, undergoing combined AVR-CABG, which included a graft to the left anterior descending coronary artery (LAD) from 1984 to 1994 (n = 227) were examined retrospectively. RESULTS: Patients receiving an IMA graft (yesIMA, n = 135) and patients receiving only saphenous vein grafts (nonIMA, n = 92) were not different in their presenting symptoms, or in their incidence of preoperative risk factors. The patients with IMA were more likely to be male, have a later year of operation, be younger, and have a greater body surface. Morbidity was not different between groups. IMA use did not affect 30-day mortality. Long-term actuarial survival was greater in the group with IMA (63% +/- 7% vs 42% +/- 6% at 5 years, p < 0.01). A multivariate Cox proportional hazards model demonstrated that use of an IMA graft improved survival, while recent myocardial infarction, diabetes, earlier year of operation, and lower ejection fraction diminished long-term survival. The relative risk of IMA grafting was 0.570. CONCLUSIONS: Within the limits of a retrospective analysis, patients in a modern era of cardiac operation, who undergo combined AVR-CABG, do not suffer increased morbidity from IMA use, and may realize a survival benefit from use of the IMA as a conduit for bypass of the LAD coronary artery.