Which is the graft of choice for the right coronary and posterior descending arteries? Comparison of the right internal mammary artery and the right gastroepiploic artery

Coronary artery size as a predictor of Y-graft patency following coronary artery bypass surgery

This study aims to evaluate the association between target vessel size and graft patency in the right IMA-right coronary territory anastomosis.A total of 402 patients who underwent CABG between 2005 and 2016 using the right IMA Y-graft to the posterolateral branch or posterior descending artery were enrolled. Preoperative coronary angiography was utilized to measure the size of the target coronary arteries in the right territory. Follow-up angiography and computed tomography at 6 to 12 months were used to determine graft patency.Thirty patients (7.5%) were found to have occluded graft. Larger target vessel size was associated with lower risk of graft occlusion (OR: 0.18, 95% CI:0.05-0.62, P = .007). The receiver operating characteristic (ROC) curve showed that the cutoff-value of 1.93 mm was found to have the maximum sum of sensitivity and specificity for graft patency (Area under the curve (AUC): 0.65, P = .01). Excluding patients with right coronary artery total occlusion, the discriminative performance of target vessel size became more prominent (AUC: 0.76, P < .01), with same cutoff value.In the setting of bilateral IMA composite grafting, the patency of right IMA to right coronary territory was influenced by the size of the target coronary artery. The influence of target coronary artery size was prominent in non-total occlusion patients. Careful selection of a target anastomosis site is recommended.

[Effect of the degree of stenosis of the right coronary artery on remote results of bypass grafting]

AIM

The purpose of this study was to assess the long-term results of right coronary artery bypass grafting and identify predictors of coronary artery bypass graft occlusion.

PATIENTS AND METHODS

Our retrospective single-centre study included a total of 245 patients subjected to isolated coronary artery bypass graft operations during the follow up period from 2010 to 2015. All patients endured bypass grafting of the right coronary artery (RCA) with either autovenous or autoarterial conduits. Control coronary bypass angiography was performed in all patients in connection with a relapse of angina pectoris. The duration of the follow up period amounted to 43.7±20.2 months. The patients were divided into two groups depending on the type of the conduit used to bypass the RCA. Group One patients (n=106) endured bypass grafting of the RCA and its branches using the internal thoracic artery. Group Two patients (n=139) underwent autovenous coronary artery bypass grafting of the RCA basin. By the main clinical, demographic and intraoperative parameters the groups were statistically homogeneous (p>0.05). The effect of the degree of proximal stenosis, the diameter of the grafted artery on the viability of bypass grafts was assessed.

RESULTS

During the follow-up period up to 84 months, 19 (17.9%) occluded arterial and 29 (20.9%) venous conduits were revealed. The Kaplan-Meier analysis showed that the probability of the absence of venous graft occlusion during the follow-up period up to 84 months was significantly lower than that of arterial grafts (log rank=0.012). The Cox regression analysis results revealed that shunt occlusion was influenced by the degree of proximal stenosis and the diameter of the shunted artery.

CONCLUSION

When shunting a moderate stenosis of the RCA (up to 70%), an advantage of autovenous conduits was revealed. When shunting the RCA with a critical stenosis and occlusion, advantages were revealed for the internal thoracic artery.

Contemporary use of arterial and venous conduits in coronary artery bypass grafting: anatomical, functional and clinical aspects

Although the benefits of using the left internal mammary artery to bypass the left anterior descending artery (LAD) have been extensively ascertained, freedom from major cardiovascular events and survival after coronary artery bypass grafting (CABG) also correlate with the completeness of revascularisation. Hence, careful selection of the second-best graft conduit is crucial for CABG success. The more widespread use of saphenous vein grafts contrasts with the well-known long-term efficacy of multiple arterial grafting, which struggles to emerge as the procedure of choice due to concerns over increased technical difficulties and higher risk of postoperative complications. Conduit choice is at the discretion of the operator instead of being discussed by the heart team, where cardiologists are not usually engaged in such decisions due to a hypothetical lack of technical knowledge. Furthermore, according to the ESC/EACTS guidelines, traditional CABG remains the gold standard for multi-vessel coronary artery disease with complex LAD stenosis, but hybrid procedures using percutaneous coronary intervention for non-LAD targets could combine the best of two worlds. With the aim of raising the cardiologist's awareness of the surgical treatment options, we provide a comprehensive overview of the anatomical, functional and clinical aspects guiding the decision-making process in CABG strategy.

Celiac artery stent placement for coronary ischemia

INTRODUCTION

The use of endovascular technology for mesenteric interventions has become an increasingly accepted treatment modality. We present an unusual case of celiac artery stent placement for coronary ischemia.

CASE DESCRIPTION

A 66-year-old male with a history most notable for coronary artery disease and coronary artery bypass grafting (CABG) x 3 utilizing left internal mammary artery to left anterior descending, radial artery to first diagonal and his right gastroepiploic artery (GEA) to posterior descending artery presented with chest pain. His work-up included a cardiac catheterization that revealed a 90% stenosis at the origin of the celiac axis. A subsequent computerized tomography angiogram confirmed this and noted moderate stenosis of his superior mesenteric artery (SMA) as well as severe inferior mesenteric artery (IMA) stenosis. The patient was taken for mesenteric angiography by vascular surgery at which time he underwent balloon-expandable stent placement in the celiac axis. The patient tolerated this procedure well and was noted to have an improvement in his symptoms postoperatively.

DISCUSSION

Use of arterial conduits for CABG have proven to be superior to vein. Long-term viability of the GEA as a conduit is dependent in part on the patency of mesenteric circulation. Our findings demonstrate a viable endovascular treatment option for angina pectoris secondary to mesenteric stenosis in this unique patient population.

Concomitant grafting of both postbifurcation internal thoracic artery branches

OBJECTIVE

We aimed to assess the clinical outcome and graft patency after concomitant grafting of both postbifurcation internal thoracic artery (ITA) branches.

METHODS

Between 2007 and 2013, 17 patients (14 men; mean [SD] age, 60 [9.3] years) underwent skeletonized bifurcated ITA grafting. Respective targets were restricted to non-left anterior descending (LAD) area. In all patients, a complementary standard ITA was used to graft the LAD artery. Graft patency was assessed by standard coronary angiography or serial multidetector computed tomography.

RESULTS

Of the bifurcated conduits, 94% were right ITA. Respective right ITA target sets were first and second obtuse marginal arteries (M1-M2) (n = 12), ramus-M1 (n = 2), and distal right coronary artery-posterior descending artery (n = 2). Right ITAs were mobilized retroaortic (via the transverse sinus) in 14 patients (82%) (to circumflex artery targets). Circumflex artery targets comprised 88.2% of all anastomoses (30/34). There were no early mortalities, myocardial infarctions, or hypoperfusion syndromes. During median follow-up of 44 months (range, 3-63), there was no late mortality. Overall reintervention rate was 11.7%, and bifurcated ITA-related reintervention rate was 5.8%. At 5 years, freedom from major adverse cardiac or cerebrovascular event related to bifurcated ITA respective territory was 87% (Kaplan-Meier). Coronary imaging was achieved in 76% of the patients (elective multidetector computed tomography, n = 9; symptoms-directed coronary catheterization, n = 4). Bifurcation branch patency rate was 88.4% (23/26) at a median of 3.5 years.

CONCLUSIONS

Grafting both postbifurcation ITA branches is technically feasible and may be selectively considered. Current observations are valid for skeletonized conduits and limited to non-LAD targets. These preliminary findings should be corroborated by larger data sets.

Bilateral internal mammary artery grafting

The superiority of the left internal mammary artery over the saphenous vein graft led many surgeons to adopt bilateral internal mammary artery (BIMA) as a good surgical option for further improving late outcome of patients undergoing myocardial revascularization. However, routine use of BIMA was limited by some potential drawbacks: the increase of deep sternal wound problems, especially in diabetic patients; the shortness of right internal mammary artery (RIMA), which limited its utilization as an in situ graft; the low patency rate if grafted to the right coronary artery; and the longer operative time. The skeletonization of the internal mammary artery along with a better glucose control in diabetic patients significantly reduced the incidence of deep sternal problems. Another problem to solve was finding the optimal target of the RIMA. The general consensus is that RIMA appears to be more efficient if grafted to the lateral wall. The Y or T configuration of double mammary arteries could be more helpful to reach the lateral target vessels. Finally, recent reports clearly demonstrate the superiority of BIMA over single internal mammary artery in terms of survival or quality of life. The latter finding has also been reported in diabetic patients.

Total arterial revascularization in triple-vessel disease with off-pump and aortic no-touch technique

BACKGROUND

We evaluated the outcomes in patients who have undergone total arterial revascularization using the bilateral internal thoracic arteries (BITA) with off-pump and aorta no-touch technique.

METHODS

From March 2001 to September 2007, 512 consecutive patients with triple-vessel disease underwent total arterial revascularization with off-pump and aortic no-touch technique, using BITA or the right gastroepiploic artery (RGEA) in addition to BITA. Only BITA grafts were used for bypass to coronary arteries in 353 patients, and additionally in situ RGEA was bypassed to right coronary arteries in 159 patients. The mean number of distal anastomoses was 4.15 +/- 0.8 per patient.

RESULTS

One 30-day death occurred. Deep sternal wound infection occurred in 2 patients. The rate of perioperative stroke was 0.8%. The patients were followed for as long as 6 years (mean follow-up, 37.9 +/- 17.7 months). The 1-year and 5-year actuarial freedom from cardiac death was 98.3% and 96.7%, respectively. The 1-year and 5-year actuarial freedom from cardiac events was 97.1% and 89.3%, respectively. Using RGEA was a significant predictor of cardiac event-free survival (p = 0.046).

CONCLUSIONS

Total arterial revascularization using off-pump coronary bypass and aortic no-touch techniqe with BITA grafts was safe and effective, with low mortality among patients with triple-vessel disease. Patients undergoing in-situ RGEA grafting for right coronary arteries appeared to have fewer cardiac events than did patients undergoing only BITA grafting in triple-vessel disease.

Early outcome of a randomized comparison of off-pump and on-pump multiple arterial coronary revascularization

BACKGROUND

Previous randomized comparisons of off-pump and on-pump coronary artery bypass grafting (CABG) have yielded controversial results about the cardiac and neurological events and graft patency. In addition, these randomized studies were composed of CABG with a few arterial grafts. We performed a prospective randomized controlled study to compare off-pump and on-pump CABG with multiple arterial grafts.

METHODS AND RESULTS

Between July, 2002, and September, 2004, 167 consecutive unselected patients referred for elective primary CABG were randomly assigned to undergo multiple arterial off-pump CABG (n=81) or on-pump CABG (n=86). The clinical outcomes and S-100 protein, neuron-specific enolase, and maximum creatine kinase-MB levels were compared. Early graft patency was examined within 3 weeks after the operation by angiography. The number of grafts performed per patient (3.5+/-1.0 for off-pump CABG and 3.6+/-0.9 for on-pump CABG) and the number of arterial grafts performed per patient (3.3+/-1.0 for off-pump CABG and 3.4+/-0.9 for on-pump CABG) were similar. Completeness of revascularization (completed grafts/planned grafts) was 98% in both procedures. There were no hospital deaths in either group. The operation time was significantly (P<0.001) shorter in the off-pump group than in the on-pump group (267+/-60 minutes versus 307+/-59 minutes). The incidence of perioperative complications was similar. The frequency of no need for transfusion was higher in the off-pump group than in the on-pump group (80% versus 55%, P<0.001). The S-100 protein levels at the admission into the intensive care unit were significantly (P<0.001) lower in the off-pump group than in the on-pump group (0.20+/-0.11 ng/mL versus 0.34+/-0.22 ng/mL). The neuron-specific enolase levels at the intensive care unit admission were significantly (P<0.001) lower in the off-pump group than in the on-pump group (10.4+/-9.0 ng/mL versus 16.9+/-6.9 ng/mL). Maximum creatine kinase-MB levels were significantly (P=0.046) lower in the off-pump group than in the on-pump group (17.1+/-16.7 IU/L versus 21.5+/-10.6 IU/L). The overall early graft patency rate with or without stenosis was the same (98%) in both groups, but the rate without stenosis was slightly worse in the off-pump group (93%) than in the on-pump group (96%) (P=0.093). The stenosis-free patency rate in the right coronary area was significantly (P=0.028) worse in the off-pump CABG group (90%) than in the on-pump group (99%).

CONCLUSIONS

Off-pump CABG with multiple arterial grafts was as safe as the conventional on-pump CABG, with similar completeness of revascularization and early graft patency.

Using the Bilateral Internal Mammary Artery in the Left or Right Coronary Artery System: 5-Year Comparison of Operation Techniques and Angiographic Results

OBJECTIVE

Using the bilateral internal mammary artery (IMA) in coronary artery bypass grafting (CABG) surgery has prolonged survival, improved functional capacity, and reduced the rate of reintervention without increasing postoperative early morbidity and mortality.

METHODS

Between January 1996 and December 1997, 94 CABG operations were performed using the bilateral IMA. In Group A (n = 45), the right IMA was anastomosed to the left coronary artery system; in Group B (n = 49), the right IMA was anastomosed to the right coronary artery system. The left IMA was always anastomosed to the left coronary artery system in both groups.

RESULTS

There was 1 death (Group A) (1.06%), and 1 late death (Group B) (1.07%). One patient in Group A underwent balloon angioplasty, and 1 patient in Group B underwent reoperation after the follow-up. Pre- and postoperative data were similar between both groups, except for off-pump CABG, which was higher in Group B (2.2% versus 36.7%; P <.001). Twenty-three randomized patients in each group underwent control angiography until May 2002. Angiographic results showed that the patency of the right IMA to the right or left coronary artery system was similar (78.26% versus 82.6%; P = .7). But the left IMA had a better patency rate than the right IMA (95.65% versus 80.43%; P = .02). The patency rates of the left and right IMA anastomosis on the beating heart in Group B were not significantly different (92.3% versus 76.9%; P = .27). The patency of right IMA anastomosis with or without off-pump technique in Group B was similar (76.9% versus 80%; P = .84).

CONCLUSIONS

Bilateral IMA can be used with low morbidity and mortality. The angiographic and clinical results of off-pump CABG show that bilateral IMA can also be used in off-pump surgery with similar results.

Revascularization of the Right Coronary Artery: Grafting or Percutaneous Coronary Intervention?

BACKGROUND

The choice of myocardial revascularization strategy for the right coronary artery (RCA) in patients with multivessel disease and chronic stable angina remains controversial. Our aim was to determine the better strategy-hybrid, combining bypass of the left coronary network and percutaneous coronary intervention of the RCA, or exclusively surgical-and if the latter, the best conduit.

METHODS

We used decision analysis, a modeling technique, to compare two RCA revascularization strategies: surgical grafting and percutaneous coronary intervention. A review of the English language literature determined the variables for each strategy. All possible outcomes of each strategy were analyzed to determine the baseline strategy yielding the highest expected effectiveness. Sensitivity analysis determined the most relevant elements in the model and indicated threshold values.

RESULTS

Arterial grafting of the RCA led to the highest expected effectiveness, respectively 6% and 7% higher than that of percutaneous coronary intervention and the saphenous graft procedure. Of the arteries available-the radial, right gastroepiploic, and right internal thoracic artery-the most effective was the right internal thoracic artery, pedicled for the proximal part of the RCA and free connected as a Y or a T to the pedicled left internal thoracic artery for the distal part of the RCA. Sensitivity analysis showed surgery to be the appropriate strategy when the expected 1-year patency rate of the arterial graft exceeded 80%.

CONCLUSIONS

This analysis shows arterial grafting of the RCA to have better outcomes than percutaneous coronary intervention, and the right internal thoracic artery to be the best conduit.

Early and late outcome of skeletonised bilateral internal mammary arteries anastomosed to the left coronary system

OBJECTIVES

To investigate in a retrospective study the technical aspects of using the in situ bilateral internal mammary arteries (IMAs), with the right IMA (RIMA) used for revascularisation of the circumflex system, and to evaluate early and late outcome.

MATERIALS AND METHODS

Between January 1997 and July 2003, 552 consecutive patients underwent grafting of the circumflex artery system with an in situ skeletonised RIMA routed through the transverse sinus (eventually retrocaval). Mean (SD) age was 63.8 (11) years. 331 (60%) patients underwent total arterial myocardial revascularisation. Mean follow up was 26 (9) months.

RESULTS

The success rate of skeletonised RIMA grafting to the circumflex branch was 100%. There were 19 (3.4%) in-hospital deaths. Perioperative myocardial infarction occurred in 12 (2.2%) patients. In 155 patients undergoing postoperative angiography, two had an occluded RIMA and a string-like phenomenon was seen in three RIMA and one left IMA (LIMA). Three RIMA and three LIMA had stenotic lesions. The patency rates of RIMA and LIMA were 94% and 97.4%, respectively. Strong predictors of non-functional IMA grafts were a recipient coronary artery diameter of < 1.5 mm (p = 0.022), < 60% stenosis of the recipient coronary artery (p = 0.015), diffuse stenotic lesions of the recipient coronary artery (p = 0.018), and a small IMA calibre (p = 0.0001). Cumulative actuarial survival at three years was 96.4% and event-free cumulative survival was 93.8%.

CONCLUSIONS

Use of the bilateral IMAs offers the possibility of constructing various configurations, making total arterial myocardial revascularisation possible with a minimum number of arterial conduits. Use of the skeletonised RIMA through the transverse sinus and eventually retrocavally can reach most branches of the circumflex system and is associated with an excellent patency rate. Patients who received bilateral IMA grafts for left coronary system revascularisation had improved early and late outcomes and decreased risk of death, reoperation, and angioplasty.

Assessment of Myocardial Viability by Cardiovascular Magnetic Resonance

Patients with ischemic heart disease may have left ventricular (LV) dysfunction due to reversible or irreversible causes. The ability to distinguish viable myocardium with dysfunction due to a reversible etiology (hibernation, stunning) from nonviable scar is critical for determining proper management of the patient. Cardiovascular magnetic resonance (CMR) is a technique that has been established to be useful for the detection of myocardial viability and advancements in the field promise to further increase its utility. In this review we describe the features of CMR that make it suited for this purpose and outline promising developments that may soon make CMR the reference standard for viability assessment.

Internal mammary artery

The internal mammary artery (IMA) has been already used in some pioneering experiences since the middle of last century but it became the graft of choice only in the 1980s, after widespread angiographic and clinical demonstration of its superiority over the saphenous vein graft (SVG). The use of both mammary arteries was then explored in order to achieve better long-term results when compared to single IMA and SVG. The IMA can be harvested pedicled or skeletonized and used as an in situ graft or as a source for composite graft (Y-graft, lengthened graft). When the bilateral internal mammary artery (BIMA) is grafted in situ, the left internal mammary artery (LIMA) is generally used for the left descending artery (LAD) and the RIMA for the right coronary artery (RCA), or for the lateral wall, usually going through the transverse sinus. In the case of Y-graft, the left coronary system is more frequently chosen as the target site of revascularization. Our experience shows that: (1) The use of IMA provides better 15-year clinical results when compared to SVG. (2) The use of BIMA in patients younger than 75 years can produce higher 10-year freedom from cardiac-related events than the single one, even in diabetic patients.

Rationale of off-pump coronary artery bypass grafting for left main trunk disease

OBJECTIVE

Off-pump coronary artery bypass grafting (OPCAB) remains controversial in patients with left main trunk (LMT) disease because of a concern about the ability to tolerate hemodynamic instability. This study examined the safety of OPCAB for LMT disease compared with conventional coronary artery bypass grafting (CABG).

METHODS

Between April 1997 and December 2002, 257 consecutive patients with LMT stenosis who underwent CABG were enrolled. There were 98 patients who received CABG with the aid of cardiopulmonary bypass (CCAB group), and 159 patients who received OPCAB (OPCAB group).

RESULTS

There was no patient who converted to on-pump intraoperatively due to hemodynamic instability. Both intraoperative blood loss and blood transfusion incidence were lower in the OPCAB group. Postoperative course was similar, however, pulmonary complications were less observed postoperatively in the OPCAB group. No hypoperfusion syndrome was seen postoperatively in both groups. The average number of anastomosis was 3.2+/-1.1 in the CCAB group and 3.2+/-1.0 in the OPCAB group (p=0.645). Total arterial OPCAB with an aorta no-touch technique was achieved in 142 patients (89.3%) in OPCAB group. Postoperative angiography was performed in 95 patients in CCAB (96.9%), and in 141 patients in OPCAB (89.8%). Although graft patency of arterial grafts was good in both groups (100% in CCAB and 98.3% in OPCAB), saphenous vein graft patency was slightly lower in both groups (93.4% in CCAB and 76.5% in OPCAB) compared with arterial grafts.

CONCLUSION

OPCAB allows a safe and effective treatment of LMT disease.

Skeletonized Gastroepiploic Artery for Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Skeletonized arterial grafting may reduce the risk of graft spasm and may improve graft patency. Previously we reported a pilot study of skeletonized gastroepiploic artery (GEA) grafting with favorable results. Skeletonized GEA harvesting with an ultrasonic scalpel has now become our routine procedure. In this report, we compare the early clinical outcomes of skeletonized versus pedicled GEA grafting to assess the safety and benefit of use of skeletonized GEA in coronary artery bypass grafting.

METHODS

Between July 2002 and October 2003, the GEA was used as a conduit for isolated off-pump coronary artery bypass grafting in 105 patients. Of these, 21 patients (group P) received pedicled GEA and 59 patients (group S) received skeletonized GEA grafts (excluding 25 patients whose results were reported in the pilot study). The perioperative and early follow-up data were prospectively collected and compared.

RESULTS

No graft injury was found in either group. The preoperative characteristics were similar in the two groups except that group S had a smaller body surface area (1.64 +/- 0.16 m 2 in group S versus 1.73 +/- 0.16 m 2 in group P, P <.05) and a significant number of patients with diabetes (36/59, 61.0% versus 7/21, 33.3%, P <.05). The number of distal anastomoses was 4.3 < 1.0 versus 3.9 +/- 0.9 ( P = not significant [NS]). An in situ GEA composite graft was constructed in 8 (13.6%) of the patients in group S and none of the patients in group P ( P = NS). There was one hospital death due to infection in group S. Otherwise, there were no cases of low output syndrome or postoperative myocardial infarction in either group. During early postoperative follow-up, no angina recurrence or myocardial infarction was found.

CONCLUSION

The GEA can be skeletonized safely with an ultrasonic scalpel. Skeletonization enables a wider variety of choices in the use of GEA grafting.

In situ retrocaval skeletonized right internal thoracic artery anastomosed to the circumflex system via transverse sinus: Technical aspects and postoperative outcome

BACKGROUND

The aim of this study was to investigate whether, by using the in situ right internal thoracic artery via the transverse sinus (eventually retrocaval), both the proximal and distal major branches of the circumflex system could be grafted and to evaluate the early and late outcome in these patients.

METHODS

Between January 1997 and March 2002, 452 consecutive patients underwent grafting of the circumflex system with the in situ skeletonized right internal thoracic artery routed via the transverse sinus. The mean age was 62.4 +/- 10.3 years. A mean of 2.2 +/- 0.3 arterial grafts per patient were used, and 271 (60%) patients underwent total arterial myocardial revascularization. At 3 months after surgery, 86 patients (right Y or T graft) underwent echo color Doppler imaging before and after an adenosine provocative test. The mean follow-up was 27 +/- 8 months.

RESULTS

The success rate of skeletonized right internal thoracic artery grafting to the circumflex system branch was 100%. There were 15 (3.4%) hospital deaths. In 116 patients who underwent postoperative angiography, the total patency rates of the right and left internal thoracic arteries were 94% and 96.6%, respectively. Strong predictors for nonfunctional internal thoracic artery grafts were a small internal thoracic artery caliber (P <.001), recipient coronary artery diameter less than 1.5 mm (P =.012), stenotic lesions of less than 60% (P =.016), and diffuse stenotic lesions (P =.015) of the recipient coronary artery. In 86 patients who underwent postoperative echo color Doppler imaging, the flow reserves at the main stem of the left and right internal thoracic arteries were 2.24 +/- 0.5 and 2.48 +/- 0.6, respectively. Cumulative actuarial survival at 3 years was 96.3%, and event-free cumulative survival was 93%. The Cox model revealed a left ventricular ejection fraction of less than 35% (P =.016), age greater than 70 years (P =.025), New York Heart Association grade greater than III (P =.0019), nontotal arterial myocardial revascularization (P =.002), and the preoperative presence of more than 1 ischemic area (P <.001) as strong predictors for poor overall cumulative event-free survival.

CONCLUSIONS

The skeletonized right internal thoracic artery, placed via the transverse sinus and eventually retrocaval, can reach most branches of the circumflex system and is associated with an excellent patency rate. The predictors for poor overall event-free survival seem to be similar to those of the general population undergoing conventional coronary artery bypass grafting. Use of bilateral internal thoracic arteries and in situ right internal thoracic artery grafting via the transverse sinus offers the possibility of various configuration constructions, making possible total arterial myocardial revascularization with a minimum number of arterial conduits.

Long-term patency of the right internal mammary artery used as a coronary bypass conduit and the effect of the recipient vessel

This study reviewed our experience with the long-term patency of the right internal mammary coronary artery (RIMA) bypass graft in 58 patients over 1 year. Thirty-one percent (n = 18) of patients had obstructive lesions in the RIMA. In vessels with any lesion, the percent stenosis was 85.5% (range 30% to 100%). Eleven of 38 patients (28%) with right-sided recipient vessels had significant stenosis, whereas 21% of left-sided recipient vessels had significant stenosis of the RIMA. When compared with left internal mammary artery grafting, the long-term patency of the RIMA was lower than expected and warrants larger prospective studies.

Limits of arterial myocardial revascularization

A prospective study of myocardial blood perfusion after coronary artery bypass graft (CABG) was conducted in two groups of patients. In group 1, a two-year assessment by exercise thallium myocardial scintigraphy without medical treatment was performed in 122 patients who consecutively underwent CABG with exclusive use of both internal mammary arteries (IMA) and gastroepiploic artery (GEA). In group 2, myocardial function and perfusion were determined by radionuclide investigations performed before and one year after CABG in 100 patients with preoperative LV dysfunction (defined as LV ejection fraction (LVEF) less than 0.40), comparing results of myocardial revascularization performed with either exclusive arterial grafts (arterial group, 54 patients) or one arterial graft (IMA) associated with a sequential vein graft (vein group, 46 patients). In group 1, 21% of patients presented silent residual electric ischemia during exercise stress testing and 26% had reversible scintigraphic ischemic defect despite complete revascularization, 18% of those in the inferior wall bypassed with GEA and 8% in the anterior wall bypassed with the right IMA. In group 2, the significant preoperative ischemia significantly decreased in both the vein group and the arterial group. LV function was significantly improved in the vein group; in contrast there was no modification of LV function in the arterial group. A multivariate analysis showed that the surgical technique used and the preoperative LVEF were independent prognostic factors of the postoperative myocardial outcome, with a positive impact of the vein use on the postoperative myocardial function recovery. It is important to recognize that arterial grafts have some limitations in the ability to supply blood flow for coronary circulation that may induce postoperatively silent residual myocardial ischemia and a lack of LV function recovery.

Graft of choice to right coronary system in left-sided bilateral internal thoracic artery grafting

BACKGROUND

The complementary graft of choice to the right coronary artery system in patients undergoing left-sided bilateral internal thoracic artery grafting has yet to be determined. Saphenous vein graft (SVG) was compared with right gastroepiploic artery (RGEA) as the supplemental conduit to the right coronary artery when left-sided bilateral internal thoracic artery grafting is implemented.

METHODS

From April 1996 to July 1999, 234 patients underwent bilateral internal thoracic artery grafting to the left coronary system with RGEA grafted to the posterior descending artery (RGEA group). They were compared with 127 patients with left-sided bilateral internal thoracic artery in whom SVG was used for grafting the right coronary system (SVG group).

RESULTS

Female sex (27% versus 14.5%), diabetic patients (40% versus 27%), emergency cases (21% versus 7.3%), and left main coronary artery disease (34% versus 23%) were more prevalent in the SVG group. Number of grafts per patient was higher in the SVG group (3.8 versus 3.5, p = 0.04). Thirty-day mortality was 3.9% in the SVG and 2.6% in the RGEA group (not significant). Occurrence of postoperative complications (myocardial infarctions, strokes, bleeding, and sternal infections) was similar. Return of angina was similar (1.6% versus 3.8% in the SVG and RGEA groups, respectively). Midterm follow-up (4 to 56 months) showed comparable 1-year and 4-year survival (Kaplan-Meier) for both groups (92.8% and 91.7% in the SVG group, and 94.7% and 88% in the RGEA group, respectively).

CONCLUSIONS

In patients undergoing left-sided bilateral internal thoracic artery grafting, the use of RGEA for revascularization of the right coronary system does not confer clinical benefits over SVG after midterm follow-up.

Redo off-pump coronary artery bypass grafting for high risk hemodialysis patients

BACKGROUND

The number of reoperative (redo) coronary artery bypass grafting (CABG) for patients with long-term hemodialysis has been increasing. Off-pump CABG (OPCAB) may decrease risks associated with redo CABG.

METHODS

Two patients on chronic hemodialysis with calcification of the ascending aorta underwent redo double coronary OPCAB for the left anterior descending artery (LAD) and the posterior descending artery (PDA) via median sternotomy. The LAD was bypassed with the left internal thoracic artery (LITA). The PDA was exposed with minimum dissection and bypassed with a composite graft of the right internal thoracic artery (RITA) and the saphenous vein (SV).

RESULTS

Both patients made a quick recovery with no complications and one had postoperative angiography that showed the patent grafts. Both patients were free from angina pectoris at follow-up of 6 months and 3 months, respectively.

CONCLUSION

Redo OPCAB of the LAD and PDA can be performed with minimal dissection via median sternotomy using the LITA and a composite graft of the RITA and SV.

Coronary artery bypass grafting using the gastroepiploic artery in 1,000 patients

BACKGROUND

The gastroepiploic artery (GEA) has been used as a graft in 1,000 patients in our institution, and the clinical outcome and the angiographic long-term results were reviewed.

METHODS

Between June 1, 1991, and June 30, 2001, 1,000 consecutive isolated coronary artery bypass grafting procedures using the GEA were performed in the Shin-Tokyo Hospital Group. The perioperative data were retrospectively analyzed, and the late angiographic results, cardiac related events, and survival were examined. The end points of the follow-up study were death or the occurrence of a cardiac-related event.

RESULTS

The GEA was used in 767 men and 233 women (mean age, 63.8 +/- 9.4 years). The GEA was used as an in situ graft in 99.6% of patients and was anastomosed to the right coronary artery in 87.8% and the circumflex artery in 10.0%. In addition, the left internal mammary artery was used in 96.9% of patients, the right internal mammary artery in 28.5%, the radial artery in 41.7%, the inferior epigastric artery in 1.4%, and the saphenous vein in 40.1%. The hospital morbidity and mortality rates were 10.8% and 0.8%, respectively. No abdominal complications were observed. Postoperative myocardial infarction associated with GEA graft failure occurred in 2 patients. During the late follow-up of 4.0 +/- 2.3 years, cardiac-related events were observed in 155 patients. The actuarial 3- and 5-year event-free rates were 91.2% and 84.2%, respectively. There were 86 late deaths, 36 of which were cardiac related deaths. The actuarial 3- and 5-year survival rates were 96.6% and 92.6%, respectively. Angiography was performed on 437 patients within 1 year after operation and in 221 patients more than 1 year postoperatively (mean interval, 3.1 +/- 1.8 years). The actuarial 1-, 3-, and 5-year GEA graft patency rates were 98.7%, 91.1%, and 84.4%, respectively, and the actuarial 1-, 3-, and 5-year LIMA graft patency rates were 99.6%, 98.8%, and 97.0%, respectively (p < 0.0005).

CONCLUSIONS

The GEA was used for coronary artery bypass grafting with good perioperative results. However, the angiographic patency rate of the GEA was inferior to that of the internal mammary arteries. The late occurrence of angina attributed to GEA graft failure should be carefully monitored.

Complementary saphenous grafting: long-term follow-up

OBJECTIVE

Recently we reviewed the 10-year clinical and angiographic outcomes of sequential internal thoracic artery grafting. Most of the patients also received complementary saphenous grafts, and their overall long-term patency rates were surprisingly high. Therefore, we decided to analyze these results in more detail.

METHODS

The first consecutive 500 patients having received at least one sequential internal thoracic artery graft between October 1985 and August 1991 were restudied retrospectively. The saphenous grafts were only used to achieve complete revascularization in addition to complex arterial grafting on less significant or remote coronary vessels. A total of 161 patients consented to a late angiographic restudy at a mean postoperative interval of 7.5 years (1-12.2 years).

RESULTS

At 5 and 10 years postoperatively, freedom from angina was 96% and 82%, and freedom from any cardiac event was 92.8% and 69%, respectively. Only 15 (3.1%) patients needed additional revascularization (0.3% per patient-year): 4 coronary artery bypass grafting (0.8%) and 11 percutaneous transluminal coronary angioplasty (2.3%). The overall patency and intactness rates of saphenous anastomoses were 72.5% and 60.2%, respectively. There was a significant difference between the patency and intactness of sequential versus single anastomoses: 76% versus 60% and 64.5% versus 44.4%, respectively. There was no significant difference in either patency or intactness between right internal thoracic and sequential saphenous grafts anastomosed to the right coronary artery: 83.4% versus 75.2% and 77.8% versus 62.4%, respectively. The same was true for the anastomoses to the "remote area" (distal circumflex, distal right coronary artery).

CONCLUSIONS

Complementary sequential saphenous grafting still deserves consideration in some patients below 70 years of age, particularly for those with disease in the "remote area": the distal circumflex and right coronary branches.

Technical aspects and outcome of in situ right internal thoracic artery grafting to the major branches of the circumflex artery via the transverse sinus

BACKGROUND

Little is known about the anatomic limitations of in situ right internal thoracic artery (RITA) grafting to the circumflex artery.

METHODS

To evaluate the technical aspects and outcome of revascularization of the proximal and distal major branches of the circumflex artery (obtuse marginal [OM] branch and posterolateral [PL] branch), a total of 145 patients who possessed a graftable branch of the circumflex artery were enrolled into the prospective project. There were 73 patients who had the PL branch as a primary target and 72 patients with OM branches, which were allocated by a blinded observer who reviewed the preoperative angiography.

RESULTS

Changes of primary target vessels were required in 9 patients (6.2%), yielding an overall success rate of RITA grafting of 93.8%. The success rates of RITA grafting to the OM branch and the PL branch were 95.8% (69/72; CI 88.3% to 99.1%) and 91.7% (67/73; CI 83.0% to 96.9%), respectively. The univariate analysis identified grafting under hypothermic ventricular fibrillation as predictors of inability to use in situ RITA grafting for revascularization of the circumflex artery. RITA grafting to the PL branch is not identified as a predictor. Postoperative angiography in 136 patients revealed only one occlusion (0.75%) of the RITA graft anastomosed to the marginal artery. There were no significant differences in patency rates between left and right ITA grafts.

CONCLUSIONS

This prospective study showed that in situ RITA was, in most cases, able to reach most branches of the major circumflex artery and demonstrated an excellent patency rate.

Long-term results of bilateral internal thoracic artery grafting

BACKGROUND

Little is known about the long-term results of the uniform group of patients who had bilateral internal thoracic artery (ITA) grafting with the method of left ITA-to-left anterior descending coronary artery and right ITA-to-circumflex artery.

METHODS

Late follow-up study was performed in the first consecutive 203 patients (mean age, 62.6 +/- 9.1 years) who underwent isolated coronary artery bypass grafting with the left ITA anastomosed to the left anterior descending coronary artery and the right ITA to major branches of the circumflex artery. The patients were grouped according to the patency of ITA grafts demonstrated by early postoperative angiography (Both patent (BP) group, 168 patients: both ITAs showed complete patency; Not patent (NP) group, 23 patients: at least one ITA was dysfunctional).

RESULTS

Actuarial 7-year survival in all patients was 89.3% +/- 3.1%. The cumulative probability of event-free survival for cardiac death, myocardial infarction, intervention, and angina at 7 years was 96.6% +/- 1.8%, 98.0% +/- 1.5%, 86.7% +/- 3.2%, and 90.7% +/- 2.9%, respectively. NP group had more myocardial infarction and angina than the BP group, but was not statistically significant. Because of failed grafts at the early angiography, intervention was performed more frequently in NP group (p < 0.01).

CONCLUSIONS

Our results of actuarial 7-year survival and the cumulative probability of event-free survival were at least comparable to the results of other similar studies using bilateral ITA. The freedom from angina appeared to be better than in the previous study. Overall our study supports the continued use of this method of ITA grafting.

The right internal thoracic artery graft--benefits of grafting the left coronary system and native vessels with a high grade stenosis

OBJECTIVE

The left internal thoracic artery (LITA), when grafted to the left anterior descending artery (LAD), is generally accepted as the conduit of choice for coronary artery bypass grafting (CABG). In contrast, the role and efficacy of the right internal thoracic artery (RITA), despite its long-term use as a coronary artery graft, is relatively less understood. Accordingly, in this study, we sought to assess the utility of the RITA as a coronary conduit by examining the long-term patency of both in situ and free RITA grafts and analyzing the association between intraoperative graft and coronary artery variables.

METHODS

Nine hundred and sixty-two patients (LITA 962, RITA 432) who had CABG between 1985 and 1998 and underwent re-angiography for evidence of myocardial ischemia were included in this observational analysis. The diameter of the internal thoracic artery (ITA), the presence of a proximal anastomosis with the aorta, the location of the anastomosis with the coronary artery, and the coronary artery diameter, were recorded at the initial procedure. The follow-up was 67.0+/-39.4 months (mean+/-SD, range 0.1-169.5). The relationship between intraoperative variables and graft patency was assessed using Cox proportional hazard models.

RESULTS

Highest RITA failure rates were associated with grafting a native coronary artery with a stenosis of less than 60% compared with 80-100% (RR 3. 8 (95% CI, 1.9-7.2) P=0.0001). Grafts to non-LAD arteries had a higher risk of failure, the highest risk ratio being associated with grafting the right coronary artery (RR 4.0 (95% CI, 0.9-17.4) P=0.06)). Free compared with in situ grafts were also associated with a higher risk of failure with this result bordering on statistical significance (RR 1.9 (95% CI, 1.0-6.0) P=0.06))

CONCLUSION

Preference should be given to grafting arteries with a high grade stenosis or occlusion, to grafting left rather than right coronary arteries, and to using in situ rather than free ITA grafts. Passing the RITA to the left, either anterior to the aorta or through the transverse sinus, did not influence patency.

Theoretical analysis of right gastroepiploic artery grafting to right coronary artery

BACKGROUND

The right gastroepiploic artery (GEA) has been used as the second reliable arterial graft for coronary artery bypass grafting (CABG). However, concern regarding the flow competition with the recipient coronary artery has remained.

METHODS

An application of in situ GEA grafting to the right coronary artery (RCA) was studied by using a theoretical model. The theoretical model of CABG was given variables; ie, the diameters and the lengths of both in situ GEA and proximal segment of the RCA, and the degree of proximal stenosis in the RCA. According to the range of these variables obtained from clinical data, the ratio of the GEA flow to the flow of the RCA distal to the anastomosis was calculated.

RESULTS

Main factors to determine the flows in the two parallel paths were the inner diameters of both vessels, and the degree of the proximal stenosis. When the inner diameters of the GEA were 0.5 mm larger than that of the RCA, the GEA carried more than 50% of the total flow of the RCA distal to the anastomosis despite a moderate stenosis in the RCA. When the inner diameter of the GEA was equal to, or 0.5 mm smaller than, that of the RCA, the GEA flow was dominated by the native RCA flow unless the proximal stenosis was critical.

CONCLUSIONS

If the inner diameter of the GEA is 0.5 mm larger than that of the RCA, CABG with the GEA can be applied more widely. If not, the application would basically be limited.

Analysis by early angiography of right internal thoracic artery grafting via the transverse sinus : predictors of graft failure

BACKGROUND

There has been debate regarding whether technically demanding right internal thoracic artery (RITA) grafting via the transverse sinus can be extensively applied to patients in high-risk groups, such as patients with a small body size, elderly patients, and woman with relatively smaller coronary artery and internal thoracic artery (ITA) diameters.

METHODS AND RESULTS

Of the 1456 patients who underwent isolated coronary artery bypass grafting between January 1989 and December 1998 at Kumamoto Central Hospital, 393 patients (mean age, 62.4+/-9.0 years) with the RITA anastomosed to the major branches of the circumflex artery were studied. Left ITA grafting was performed in 384 patients, and in 369, the in situ left ITA was anastomosed to the left anterior descending coronary artery using standard methods. Early postoperative angiography was performed in 381 patients. The RITA was occluded in 4 patients, and string-like artery and significant stenosis were present in 11 and 7 patients, respectively; RITA graft patency was thus 94.1%. Of the preoperative variables and angiographic data, simple and multiple logistic regression analyses identified decreased severity of native stenosis, diffuse sclerosis of native vessels, and residual side branches of the ITA as independent predictors of nonfunctional grafts. The method of ITA grafting did not influence the patency of the graft.

CONCLUSIONS

The excellent patency rate demonstrated by this study, the largest angiographic study to date of RITA grafting via the transverse sinus, indicates that this technique can provide reliable revascularization of the left ventricle and that it has the potential to be applied to a wide variety of patients with diseased circumflex arteries.

Risk factors for radial artery harvest site infection following coronary artery bypass graft surgery

Radial arteries increasingly are used during coronary artery bypass graft (CABG) surgery. Although risk factors for saphenous vein harvest site infection (HSI) have been reported, rates of and risk factors for radial artery HSI are not well established. We compared rates of radial artery HSI that were detected by 2 surveillance methods, regular and heightened. Risk factors were determined by a case-control study. We identified 35 radial artery HSIs ("case sites") in 26 case patients. The radial artery HSI rate was significantly higher during heightened surveillance than during routine surveillance (12.3% vs. 3.1%, respectively; P=.002). Multivariate analysis showed that diabetes mellitus with a preoperative glucose level >/=200 mg/dL (odds ratio [OR], 4.4; P=. 01) and duration of surgery >/=5 h (OR, 3.1; P=.02) were independent risk factors for radial artery HSI. Infection is a common complication of radial artery harvesting for CABG surgery, and infection rates are dependent on the intensity of surveillance. We identified preoperative hyperglycemia and surgery duration as independent risk factors for radial artery HSI.

Vasorelaxant actions of enoximone, dobutamine, and the combination on human arterial coronary bypass grafts

Enoximone (a type III-selective phosphodiesterase inhibitor) and dobutamine (a beta-receptor agonist) are positive inotropic drugs frequently used in the postoperative management of coronary bypass surgery. The purpose of this study was to characterize their relaxant effects on the human internal mammary artery (IMA) and the gastroepiploic artery (GEA) and to test the hypothesis that their combination may have greater than additive relaxant effects. In organ baths, the relaxant effects of enoximone and dobutamine were tested on rings of IMA (n = 86) precontracted with U46619 (a thromboxane A2 mimetic), norepinephrine (NE), or KCl. The relaxant effects of dobutamine and enoximone also were tested on rings of GEA (n = 42) precontracted with U46619 and NE. The effect of the combination of enoximone and dobutamine were tested on rings of IMA (n = 24) precontracted with U46619 or NE. With respect to maximal relaxations induced by papaverine (10(-4) M), enoximone (< or =10(-3) M) caused full relaxations of IMA precontracted with NE, U46619, or KCI. Dobutamine (< or =10(-3) M) caused full relaxations of IMA precontracted with NE or KCI but only 46% (95% CI, 27-65) relaxation in the rings precontracted with U46619. Similar patterns of relaxation were observed in GEA rings, with dobutamine inducing partial relaxation in GEA precontracted with U46619. The pD2 values of enoximone and dobutamine were both significantly lower in segments precontracted with U46619. The in vitro threshold relaxant concentrations were in the upper limits or over the range of therapeutic plasma concentrations. The relaxant effect of the combination was significantly more important than the theoretic additive effect in IMA contracted with U46619 or NE. Enoximone and dobutamine are potent in vitro vasodilators but exert weak relaxant effects in IMA and GEA at concentrations in the therapeutic range. There is, however, a greater than additive vasorelaxant effect of the combination, suggesting that the vasorelaxant effect of the combination, in addition to the additive inotropic effect, may be beneficial to patients undergoing coronary bypass grafting.

Abdominal abscess: late complication after gastroepiploic coronary artery bypass grafting

The gastroepiploic artery is widely used an arterial conduit during coronary artery revascularisation surgery. We report an unusual complication of a 56-year-old man who developed a late intra-abdominal abscess extending into the mediastinum adjacent to the right ventricle more than 2 years after surgery. This was managed with percutaneous drainage and the patient made a full recovery. The case illustrates the potential problems associated with harvesting of this artery and the need for careful haemostasis.

Initial experience with MIDCAB grafting using the gastroepiploic artery

BACKGROUND

Minimally invasive direct coronary artery bypass grafting with the gastroepiploic artery can be used in primary operations and reoperations to revascularize the inferior or anterior surface of the heart.

METHODS

Patients who had symptomatic coronary artery disease limited to a single coronary distribution were selected. Coronary targets were grafted with the pedicled gastroepiploic artery through a small midline epigastric incision. Patients were followed with scheduled outpatient clinic visits, Doppler examination, and selective recatheterization.

RESULTS

Between May 1995 and November 1997, 74 patients underwent gastroepiploic artery minimally invasive direct coronary artery bypass grafting; 33 (45%) had a primary operation and 41 (55%), a reoperation. Grafting was performed to the distal right coronary artery (n = 38), the posterior descending artery (n = 28), or the distal left anterior descending coronary artery (n = 8). There were six deaths (8%) within 30 days after operation. Twenty patients (28%) underwent recatheterization; there were two graft occlusions, two graft stenoses, and five anastomotic stenoses. Of 60 patients seen 2 or more weeks after operation, 53 (88%) had resolution of anginal symptoms at a mean follow-up of 10.9 months (range, 0 to 30 months).

CONCLUSIONS

Inferior minimally invasive direct coronary artery bypass grafting with the gastroepiploic artery avoids the risks of repeat sternotomy, aortic manipulation, and cardiopulmonary bypass. Patency rates, however, were lower than expected, and there is significant morbidity and mortality associated with high-risk patients undergoing the procedure. Continued follow-up is essential to evaluate long-term graft patency and patient survival.

Two internal thoracic artery grafts are better than one

OBJECTIVE

Does the use of bilateral internal thoracic artery (ITA) grafts provide incremental benefit relative to the use of a single ITA graft?

METHODS

We conducted a retrospective, nonrandomized, long-term (mean follow-up interval of 10 postoperative years) study of patients undergoing elective primary isolated coronary bypass surgery who received either single (8123 patients) or bilateral ITA grafts (2001 patients), with or without additional vein grafts. Multiple statistical methods including propensity score matching, and multivariable parsimonious and nonparsimonious risk factor analyses were used to address the issues of patient selection and heterogeneity.

RESULTS

In-hospital mortality was 0.7% for both the bilateral and single ITA groups. Survival for the bilateral ITA group was 94%, 84%, and 67%, and for the single ITA group 92%, 79%, and 64% at 5, 10, and 15 postoperative years, respectively (P <.001). Death, reoperation, and percutaneous transluminal coronary angioplasty were more frequent for patients undergoing single rather than bilateral ITA grafting, and this observation remained true despite multiple adjustments for patient selection, sampling, and length of follow-up. The differences between the bilateral and single ITA groups were greatest in regard to reoperation. The extent of benefit of bilateral ITA grafting varied according to patient-related variables, but no patient subsets were identified for whom single ITA grafting could be predicted to provide an advantage.

CONCLUSIONS

Patients who received 2 ITA grafts had decreased risks of death, reoperation, and angioplasty.

Long-term patency rate of right internal thoracic artery bypass via the transverse sinus

BACKGROUND

Although concern regarding patency and possible compromise of graft blood flow by routing the right internal thoracic artery (RITA) through the transverse sinus has been raised, little is known about long-term patency.

METHODS AND RESULTS

To evaluate long-term patency of in situ RITA bypass via the transverse sinus, our first 115 patients (94 men, 21 women; mean age, 62.5 years; range, 13 to 77 years) who were alive in 1998 were enrolled for angiographic study. Only good-caliber grafts with no occlusion, string sign, or significant stenosis were considered patent. Early postoperative angiography had been performed 2 to 3 weeks after surgery in 114 patients. The early patency rates were 97.1% for RITA and 95.4% for left internal thoracic artery (LITA) grafts. Of 109 long-term survivors, 73 (67.0%) consented to have late angiographic restudy at a mean of 59 months (range, 9 to 93 months); 89.9% of RITA and 92.3% of LITA grafts were patent. Cumulative patency rates (actuarial curves) at 6 years were 89.3% (95% CI, 85% to 94%) for RITA and 94.5% (95% CI, 92% to 97%) for LITA, the differences not reaching statistical significance (multivariate Cox analysis).

CONCLUSIONS

Our study demonstrated good long-term patency of in situ RITA bypass grafting via the transverse sinus for revascularization of the circumflex and diagonal arteries and supports its continued use.

Minimally invasive coronary artery bypass grafting using the right gastroepiploic artery without pump

OBJECTIVE

To explore the feasibility to operate on the right coronary artery and its branches utilizing the right gastroepiploic artery (RGEA) without cardiopulmonary bypass (CPB). All cases were performed since May 1996.

METHODS

A small mid-line incision including splitting of the lower sternum gave excellent exposure. The inferior surface of the heart was dissected to expose and stabilize the target vessel. The heart rate was controlled with a Diltiazem drip. CPB was not necessary in any case. The right coronary artery was bypassed in four patients, the posterior descending artery branch in five patients and the terminal circumflex of the left coronary artery in one patient. After grafting, patency of the anastomosis was demonstrated by Doppler echocardiogram.

RESULTS

No patient had perioperative mortality or complications. No patient had recurrent angina. Color Doppler echocardiographic imaging studies before discharge confirmed patency of the graft in eight of ten cases. In two cases, the gastroepiploic artery could not be visualized. Angiographic visualization was positive in four out of five cases.

CONCLUSIONS

The gastroepiploic artery is an excellent conduit for vascularization of the inferior aspect of the heart. The operation can be done using a minimally invasive technique and without the use of cardiopulmonary bypass. This approach seems especially applicable in selective reoperative cases.

Aortocoronary saphenous vein graft disease: pathogenesis, predisposition, and prevention

Aortocoronary saphenous vein graft disease, with its increasing clinical sequelae, presents an important and unresolved dilemma in cardiological practice. During the 1st month after bypass surgery, vein graft attrition results from thrombotic occlusion, while later the dominant process is atherosclerotic obstruction occurring on a foundation of neointimal hyperplasia. Although the risk factors predisposing to vein graft atherosclerosis are broadly similar to those recognized for native coronary disease, the pathogenic effects of these risk factors are amplified by inherent deficiencies of the vein as a conduit when transposed into the coronary arterial circulation. A multifaceted strategy aimed at prevention of vein graft disease is emerging, elements of which include: continued improvements in surgical technique; more effective antiplatelet drugs; increasingly intensive risk factor modification, in particular early and aggressive lipid-lowering drug therapy; and a number of evolving therapies, such as gene transfer and nitric oxide donor administration, which target vein graft disease at an early and fundamental level. At present, a key measure is to circumvent the problem of vein graft disease by preferential selection of arterial conduits, in particular the internal mammary arteries, for coronary bypass surgery whenever possible.

Reoperations with the right gastroepiploic artery without cardiopulmonary bypass

The right gastroepiploic artery (RGEA) has been utilized as the bypass conduit on the inferior surface of the heart with a minimally invasive approach. Fourteen patients had reoperative coronary bypass surgery for severely symptomatic single-vessel disease of the right coronary artery. All surgeries were performed since May 1996. A small mid-line incision including splitting of the lower sternum gave excellent exposure. The inferior surface of the heart was dissected to expose and stabilize the target vessel. The heart rate was controlled with a diltiazem drip. Cardiopulmonary bypass was not necessary in any case. The right coronary artery was bypassed in three patients, the posterior descending artery branch in ten patients, and the terminal circumflex of the left coronary artery in one. After grafting, patency of the anastomosis was demonstrated by Doppler echocardiogram. Two patients had left anterior descending artery (LAD) grafts with LIMA (left mammary artery) and RGEA grafts performed simultaneously with two port access incisions. No patient had perioperative mortality or complications. No patient had recurrent angina. Doppler color echocardiographic imaging studies before discharge confirmed patency of the graft in 13 of 14 cases. In one case, the gastroepiploic artery could not be visualized. Angiographic visualization was positive in seven cases; seven patients were not studied yet. The gastroepiploic artery is an excellent conduit for vascularization of the inferior aspect of the heart. The operation can be done with a minimally invasive technique and without the use of cardiopulmonary bypass. This approach seems especially applicable in selective reoperative cases.