Single Bypass Grafting Research Articles

Blood pressure control and renal function preservation of exvivo renal artery repair with orthotopic renal autotransplantation for complex renal artery diseases.

To assess the outcome of exvivo renal artery repair with orthotopic renal autotransplantation for patients with complex renal artery disease. The single-center study collected and analyzed the data from patients with complex renal artery disease undergoing exvivo renal artery repair with orthotopic renal autotransplantation, retrospectively. A total of 21 complex renal artery lesions from 19 patients were included. The mean blood pressure showed a significant decrease from the preoperative to the postoperative period (P< .05). Renal function kept stable for the perioperative period. No significant serum creatinine and estimated glomerular filtration rate alteration was observed compared with the immediate postoperative period (P= .439 and .904, respectively). The median renal cold ischemia time was 35.5 (76) minutes. Two patients developed perioperative complications, one with acute cholecystitis and one with acute renal failure after graft occlusion in a solitary kidney. During the median follow-up of 48months, one single bypass graft of a solitary kidney was occluded, and four grafts developed restenosis. The primary and primary-assisted patency rates at the 5-year follow-up were 81.3% and 87.5%, respectively. No deaths were observed in the follow-up period. Exvivo renal artery reconstruction with orthotopic renal autotransplantation in patients with complex renal artery disease offers stable control of blood pressure and renal function preservation, and should be considered as a potential alternative for other open surgical procedures.

Long-Term Patency of Venous Conduits Targeting the Right Coronary Artery System-Single Is Superior to Sequential bypass Grafting.

Objective: Little is known about the fate of bypass grafts to the right coronary system. To investigate the long-term patency of venous bypass grafts directed to the right coronary artery (RCA) based on postoperative angiograms and to identify predictors of graft occlusion. Methods: In this single-center study, all patients who underwent coronary angiography from 2005 to 2021 after previously undergoing isolated coronary artery bypass grafting (CABG) were included. The primary endpoint was graft occlusion over a median follow-up of 9.1 years. Results: Among a total of 1106 patients (17.0% women, 64 (57–71) years median age), 289 (26.1%) received a sequential vein graft and 798 (72.2%) a single graft. Multivariate regression revealed age (HR 1.019, CI 95% 1.007–1.032), the urgency of CABG (HR 1.355, CI 95% 1.108–1.656), and severely impaired left ventricular function (HR 1.883, CI 95% 1.290–2.748), but not gender and chronic total occlusion (CTO) as predictive factors for graft occlusion. Single conduits were found to be a predictor of graft patency (HR 0.575 CI 95% 0.449–0.737). The angiographic outcome showed an overall 10-year freedom from graft occlusion of 73.4% ± 1.6%. The 5-year (10-year) freedom from graft occlusion was 76.9% ± 2.8% (57.8% ± 4.0%) for sequential grafts and 90.4% ± 1.1% (77.8% ± 1.7%) for single grafts (log-rank p < 0.001). Conclusions: In symptomatic patients with renewed angiography, venous bypass grafting of the RCA showed acceptable long-term patency rates. Single bypass grafting of the RCA was superior to sequential grafting, which needs to be further investigated.

Minimally Invasive Valve Surgery and Single Vessel Coronary Artery Bypass via Limited Anterior Right Thoracotomy.

Coronary artery bypass grafting with aortic valve replacement (AVR) or mitral valve replacement (MVR) is traditionally performed via sternotomy. Minimally invasive coronary surgery (MICS) and minimally invasive valve surgery have been successfully performed independently. Patients with critical right coronary artery (RCA) stenosis not amenable to percutaneous intervention are candidates for valve replacement and single vessel coronary artery bypass. We present our series of six patients who underwent a concomitant valve and single vessel intervention via right thoracotomy. Between January 2011 and June 2013, six patients underwent right thoracotomy with valve replacement and single vessel bypass. Four aortic and two mitral valves were replaced and all received single vessel RCA bypass using reversed saphenous vein graft. Thoracotomy was via right anterior approach for AVR and right lateral for MVR. The patients were assessed postoperatively for overall outcomes. The average age was 74 years (range 69-81); two patients were elective (AVR-1; MVR-1) and four were urgent (AVR-3; MVR-1). For MICS AVR and MICS MVR, the average cardiopulmonary bypass time was 171 ± 30 and 169 ± 7 minutes and the average aortic cross-clamp time was 122 ± 36 and 112 ± 2 minutes, respectively. Three patients were discharged home, one patient to a nursing home, and two to rehab. No patients required conversion to sternotomy; one patient developed atrial fibrillation, and one sepsis. Concomitant valve replacement and single bypass grafting via right anterior mini-thoracotomy is a viable option for select patients, particularly in non-stentable RCA stenosis. In the appropriate patient population, combined coronary artery bypass grafting and valve surgery can be safely performed via right thoracotomy.

Ex vivo renal artery reconstruction for complex renal artery disease

The objective of this study was to evaluate long-term outcome of renal revascularization by exvivo renal artery reconstruction for complex renal artery disease. From 1987 to 2012, 23 patients (17 women; mean age, 45years) with complex renal artery lesions underwent open renal revascularization by exvivo technique. Underlying disease included fibromuscular dysplasia with aneurysm (11), atherosclerotic aneurysm (6), Takayasu arteritis (3), and other (3). Outcomes analyzed included primary, primary assisted, and secondary patency rates; antihypertensive medication requirements; renal function and preservation; and mortality. Late graft patency, renal size, and cortical thickness were analyzed by serial renal duplex ultrasound examinations. Twenty-four kidneys in 23 patients were revascularized by exvivo renal artery reconstructive techniques. Perioperative complications were limited to two patients requiring reoperation for bleeding. Renal function did not change, and there were no in-hospital deaths. During a mean follow-up of 44months, a single bypass graft occluded, requiring repeated bypass, which was performed with renal preservation. Primary, primary assisted, and secondary patency rates were 94% at 5 and 10years. Compared with preoperative values, systolic and diastolic blood pressure and the number of antihypertensive medications were reduced (P< .05) in the 18 patients with hypertension. Late renal function was preserved as measured by no change in both serum creatinine concentration and estimated glomerular filtration rate compared with preintervention values (P= .25 and P= .35, respectively). In addition, there was no difference in treated kidney size or renal cortical thickness on follow-up compared with preoperative measurements (P= .15 and P= .62, respectively). No patient required dialysis. There were three late deaths, none related to the renal procedure, providing 5- and 10-year survival of 85% and 68%, respectively. Exvivo renal artery reconstruction for complex renal artery disease confers a benefit in blood pressure while preserving renal mass and function. This technique should be considered a competitive alternative to other open surgical techniques for the management of complex renal artery disease.

Surgical Outcomes after Superior Vena Cava Reconstruction with Expanded Polytetrafluoroethylene Grafts

Graft occlusion is a problem after superior vena cava (SVC) reconstruction for thoracic malignancy. Expanded polytetrafluoroethylene (ePTFE) is considered to be an optimal material for venous reconstruction. We reviewed the hospital records of 13 patients who underwent complete resection of thoracic malignancy invading the SVC, including SVC reconstruction with ePTFE grafts. Single bypass grafting was performed in two patients (one right-sided, one left-sided) and double bypasses grafting was performed in the other patients. All patients received antithrombotic therapy after surgery. Eight patients died of recurrence or other disease during the follow-up period (range 5-41 months). Of the 24 grafts in 13 patients, graft patency was confirmed in 20 grafts in 9 patients at a mean time follow-up time of 47.8 ± 50.0 months after surgery. In the remaining four grafts in four patients, occlusion was diagnosed at a mean time of 1.25 ± 0.50 months after surgery. All obstructed grafts were left-sided bypass grafts in patients who underwent double bypass grafting, and did not result in SVC syndrome. SVC reconstruction with ringed ePTFE grafts was safe and had good outcomes. In patients who underwent double bypasses grafting, the left-sided bypass grafts were susceptible to occlusion.

Anomalous origin of the left main coronary artery. Surgical management

A 53-year-old man, with no medical history, presented with acute coronary syndrome. Coronary angiography revealed a common right ostium giving rise to both the right coronary artery and the left main coronary artery. The left interior mammary artery was used as a single bypass graft to the left anterior descending coronary artery. The patient was asymptomatic on follow-up.

Robotic Totally Endoscopic Multivessel Coronary Artery Bypass Grafting Procedure Development, Challenges, Results

Closed-chest totally endoscopic coronary artery bypass grafting (TECAB) is feasible using robotic technology. During the early phases, TECAB was restricted to single bypass grafts to the left anterior descending artery system. Because most patients referred for coronary artery bypass surgery have multivessel disease, development of endoscopic multiple bypass grafting is mandatory. Experimental work on multivessel TECAB was carried out in the early 2000s, and first clinical cases were already performed. With further technological development of operating robots, double, triple, and quadruple TECAB has become feasible both on the arrested heart and on the beating heart. To date, 161 cases of multivessel TECAB using the da Vinci telemanipulation systems are published in the literature. The main advances enabling multivessel TECAB were the availability of a robotic endostabilizer for beating heart procedures and increased surgeon skills using remote access heart-lung machine perfusion and endo-cardioplegia. Both internal mammary arteries can be harvested and both radial artery and vein graft can be used in multivessel TECAB. Y-grafting and sequential grafting are feasible. Multivessel endoscopic surgical revascularization can be combined with percutaneous coronary interventions in advanced hybrid coronary revascularization. Time requirements for multivessel TECAB are significant, and conversion rates to larger thoracic incisions are higher than those observed for single-vessel TECAB. Clinical short- and long-term outcomes, however, seem to meet the standards of open coronary bypass surgery through sternotomy. The main advantages of multivessel TECAB are a completely preserved sternum, use of double internal mammary artery even in risk groups, and a remarkably short recovery time.

Robotic Totally Endoscopic Triple Coronary Artery Bypass Grafting on the Arrested Heart: Report of the First Successful Clinical Case

Robotic technology enables "port only" totally endoscopic coronary artery bypass grafting (TECAB). During early procedure development only single bypass grafts were feasible. Because current referral practice for coronary bypass surgery mostly includes multivessel disease, performance of multiple endoscopic bypass grafts is desirable. We report a case in which a patient received a right internal mammary artery bypass graft to the left anterior descending artery and a left internal mammary artery jump graft to 2 obtuse marginal branches. The procedure was performed through 5 ports on the arrested heart using the daVinci S robotic surgical system. This is the first reported triple bypass grafting procedure using an arrested heart approach.

Revascularization of the superior mesenteric artery alone for treatment of intestinal ischemia

Objective: Complete revascularization is recommended by many authors for treatment of intestinal ischemia. The observation that postprandial intestinal hyperemia is limited to the superior mesenteric artery (SMA) has suggested to us that SMA revascularization alone should be adequate treatment. We preferentially manage intestinal ischemia with a single bypass graft to the SMA and herein update our results using this approach. Methods: Patients were identified from a prospectively established vascular surgical registry. Each patient was assessed for acute versus chronic intestinal ischemia, preoperative angiographic findings, operation used, perioperative morbidity and mortality, late symptomatic relief, cause of death, and life table–determined survival and graft patency. Graft patency was determined by follow-up angiography or duplex scanning. Results: Fifty bypass grafts to the SMA alone were performed in 49 patients (31 women, 18 men; mean age, 62 years) for treatment of intestinal ischemia. In all patients additional splanchnic arteries were available for bypass grafting. Operative indications were acute symptoms in 21 patients, 14 of whom had bowel infarction; chronic symptoms in 26 patients; and prophylaxis in conjunction with infrarenal aortic surgery in 3 patients. Thirty-two grafts originated from the aorta or an iliac artery, and 18 originated from an aortic graft. There were 40 prosthetic and 10 autogenous conduits. Perioperative mortality was 3% in patients with chronic symptoms and 12% overall. All survivors were symptomatically improved. Mean follow-up was 44 months. Nine-year assisted primary graft patency was 79%, and 5-year patient survival was 61%. Two late deaths occurred in patients with recurrent intestinal ischemia resulting from graft occlusions. Conclusions: Bypass grafting to the SMA alone appears to be both an effective and durable procedure for treatment of intestinal ischemia. Our results appear equal to those reported for “complete” revascularization for intestinal ischemia. When the SMA is a suitable recipient vessel, multiple bypass grafts to other splanchnic vessels are unnecessary in the treatment of intestinal ischemia. (J Vasc Surg 2000;32:37-47.)

Single coronary artery bypass grafting--a comparison between minimally invasive 'off pump' techniques and conventional procedures.

At present, few studies directly comparing minimally invasive and conventional coronary artery bypass grafting are available. The aim of the present study was to evaluate the clinical outcome of the two techniques. We retrospectively compared our first consecutive 20 patients undergoing minimally invasive coronary artery single bypass grafting on the beating heart (group I) with 23 consecutive patients receiving single coronary artery bypass via sternotomy using cardiopulmonary bypass and cardioplegia (group II). The procedures were performed during the period from Jan 1, 1994 to Feb 20, 1997. There were no significant differences in demographic data. Statistically significant differences were found concerning total operative time (172.6 min in group I and 149.6 min in group II P = 0.0009) and myocardial ischemic time (23.7 min local coronary occlusion time in group I and 17.6 min aortic cross-clamp time in group II P = 0.03. Patients treated minimally invasive received significantly fewer blood transfusions (25.0% vs. 69.6% P = 0.0035) and were discharged significantly earlier from the hospital (admission rate on the fifth postoperative day 68.4% in group I vs. 100.0% in group II P = 0.0004). We conclude that minimally invasive coronary artery bypass grafting on the beating heart in comparison to conventional single coronary artery bypass grafting during the learning curve requires longer operative times but can reduce blood transfusion requirements and hospital stay.

Sequential vein bypass grafting: tactics and long-term results

The sequential bypass grafting technique has many advantages over coronary artery bypass grafting with single grafts. The aim of this study was to evaluate the consequences of sequential bypass graft failure. Between 1 January 1984 and 31 December 1996, 3846 patients underwent primary coronary artery bypass vein grafting. A total of 3490 patients received sequential vein bypass grafts and 356 patients received single vein bypass grafts (9%). There were 6177 sequential bypass grafts (3490 postero-lateral grafts (56%) and 2687 in the antero-lateral position (44%)) and 1468 single grafts (972 vein grafts and 496 internal thoracic artery grafts). Overall, there were 80 hospital deaths (2.1%). Mortality in relation to type of grafts used was: 13 deaths in 356 patients with only single graft (3.7%) and 67 deaths in 3490 patients who received sequential vein grafts (1.9%). Of 3766 hospital survivors, 3731 were followed for an average of 76 months. During follow-up, 85 patients died (2.3%), 15 patients (0.4%) underwent cardiac transplantation and 52 (1.4%) had re-do coronary artery bypass vein grafting. Graft-percutaneous transluminal coronary angioplasty was performed in 56 patients (1.5%), 37/1390 single bypass grafts (2.7%) and 19/6023 sequential bypass grafts (0.3%). There were 272/6023 symptomatic sequential graft occlusions (4.5%) (182 were in postero-lateral position and 90 in the antero-lateral position). There were 66/667 single vein graft occlusions (9.9%) and 15 symptomatic internal thoracic artery graft occlusions (2.1%) during follow-up. In 97% of patients, presenting symptoms of postero-lateral sequential bypass graft occlusion took the form of a renewed angina with a myocardial infarction rate of 3% and a mortality rate of 7%. Corresponding figures for antero-lateral sequential bypass grafts were 22, 78 and 68%, and anterior single vein bypass grafts were 70, 30 and 15%, respectively. The overall 10-year survival rate in patients with sequential bypass grafts was 81.2% and the cumulative patency rate (1464 angio-controls of 2576 sequential vein grafts) was 72.2%. A symptomatic occlusion of a postero-lateral sequential vein bypass results in a low incidence of myocardial infarction with low mortality, when the terminal anastomosis is connected to a high flow vessel. An antero-lateral sequential vein bypass graft has better long-term patency than single vein bypass, but should occlusion occur, it would usually be associated with a higher myocardial infarction and mortality rates than a single vein graft. The highest risk for failure of a sequential graft in the antero-lateral position occurs when the left anterior descending artery (LAD) is small or severely diseased. In this situation the single graft technique with internal thoracic artery appears to be safer.

Coronary Artery Bypass Grafting Without Cardiopulmonary Bypass

From October 1995 until April 1996. CABG (coronary artery bypass grafting) was performed under the beating heart without CPB (cardiopulmonary bypass) in nine cases. They consisted of 7 males and 2 females ranging in age from 31 to 79 years old (mean 64.7 years). Single bypass grafting was performed in 6 cases, and double bypass grafting was done in 3 cases, involving 2 re-do cases. With regard to the major associated diseases, two patients had required chronic hemodialysis three time a week, four patients were administered with insulin for diabetes mellitus. There were other three patients with renal dysfunction not requiring hemodialysis, two patients had pulmonary problems, and one patient had Parkinson's disease. Further more two patients were older than 75th years in age. Graft anastomosis to the coronary artery was performed with 7-0 polypropylene. In one case, left thoracotomy was done to approach the heart for the anastomosis to intermediate artery, and in the other eight cases, median sternotomy was done. The grafts used in the nine cases were 4 right internal thoracic arteries, 6 left internal thoracic arteries, one gastroepiploic artery and one saphenous vein, 12 grafts in total. Subtotal gastrectomy for gastric cancer and cholecystectomy for cholecystitis was done in one patient for each. Heterologous blood transfusion was required two cases (22.2%). The postoperative course was very good in all cases. Eleven grafts in postoperative angiographed 8 cases were all patent, although presenting the string sign in one case, and angina pectoris disappeared in all cases. CABG under the beating heart without CPB was considered to be useful for the patients with considerable other diseases from the point of view of safety and ease of postoperative managements. We think that this procedure should be considered particularly for patients on chronic hemodialysis who required CABG.

Filling of multiple vessels by injection of dye into a single bypass graft

We describe the unusual filling of two coronary bypass grafts by a single injection in a patient who underwent coronary arterial bypasses surgery. The injection, made in the left internal mammary artery, filled the left anterior descending artery, a diagonal branch, and the graft of saphenous vein placed to that artery. In contrast, injection in the saphenous vein graft to the diagonal artery filled the diagonal artery, the left anterior descending artery and the left internal mammary to its point of origin. We emphasize the importance of this phenomenon.

Fifteen Years' Experience with the Internal Mammary Artery Graft

Initially, the internal mammary artery (IMA) was implanted into the myocardium, and 10 years later it was anastomosed directly to coronary arteries. Our experience with the IMA started with single attached grafts. To reduce injury to the pedicle and improve anastomotic accuracy, magnification, microsurgical techniques, and cardioplegia were introduced. After establishing excellent long-term patency of the IMA and knowing of the high incidence of obstruction in saphenous vein grafts 7 to 10 years after operation, we hypothesized that multiple IMA coronary anastomoses could improve the long-term results of coronary artery bypass grafting. Bilateral IMA, sequential IMA, and IMA Y-grafts were used to increase the number of mammary coronary anastomoses to 3.1 per patient. Early clinical results and patency evaluations are encouraging. In our experience, the IMA has evolved from being implanted into the myocardium, to a single bypass graft to the left anterior descending coronary artery, and finally to being the bypass conduit of choice supplying blood to three or more obstructed coronary arteries or their branches.

Emergency Coronary Artery Bypass Graft Surgery for Threatened Acute Myocardial Infarction Related to Coronary Artery Catheterization

In 20 patients undergoing cardiac catheterization, usually involving balloon-catheter dilation or streptokinase infusion, catheter-induced coronary artery intimal damage resulted in severe chest pain, electrocardiographic changes suggesting myocardial ischemia, and angiographic evidence of obstruction or dissection of a major coronary artery. These patients were surgically revascularized within 8 hours after the onset of the acute chest pain syndrome. Our experience with pharmacological and catheter-related manipulations to improve coronary blood flow after the ischemic episode but before operation suggested that the additional time spent in the catheterization laboratory was worthwhile. The injured coronary artery was the left anterior descending in 10 patients, the right in 8, the left main in 1 patient, and an obtuse marginal branch of the circumflex in 1. The average number of grafts per patient was 2.5; only 6 patients had single bypass grafts. In 5 patients, intraaortic balloon pumping was used either preoperatively or postoperatively. Inotropic support was used postoperatively in 5 patients, and 7 patients received lidocaine for ventricular irritability. Abnormal elevation of the serum isoenzyme of creatine kinase (CK-MB) was seen in 8 patients, and new Q waves were noted in 4 patients; 3 of these 4 patients with new Q waves also had abnormal serum CK-MB levels. Global ejection fraction obtained by the equilibrium-gated blood pool scan postoperatively was 60 ± 3%, which was similar to the 62 ± 3% obtained from the contrast-determined ventriculogram done preoperatively prior to the catheter-related injury. There were no early or late deaths, but morbidity was much higher in the group who had emergency coronary artery bypass grafting (CABG) compared with those who had elective CABG. In conclusion, emergency CABG for threatened myocardial infarction (MI) related to catheter-induced injury can be performed safely with preservation of global left ventricular function and a 20% incidence of new Q wave MI.

A rationale for the use of sequential coronary artery bypass grafts

The use of sequential coronary artery bypass grafts has been advocated because of improved graft runoff and increased blood flow through the graft with this technique. To examine the influence of runoff, quantitated in terms of coronary vascular resistance, on the velocity of blood flow through coronary artery bypass grafts, we made two sets of simultaneous pressure and flow measurements in 106 single grafts and in 35 double sequential grafts. The first set of measurements was obtained following the aortic anastomosis and the second set of measurements was made following completion of the coronary anastomosis. Resistance of the coronary bed was calculated from the two sets of measurements. The velocity of blood flow through the grafts was calculated from vein graft diameter and the second flow measurement. No significant difference was found between the diameter of single vein grafts (4.0 +/- 0.05 mm.) and sequential vein grafts (4.1 +/- 0.09 nm.). Coronary vascular resistance in the sequential grafts (100.0 +/- 15.6 RU) was lower than that in single grafts (174.6 +/- 14.6 RU, p = 0.001). Velocity of blood flow through the proximal segment of the sequential grafts (11.1 +/- 1.1 cm/sec) was higher than that through single grafts (7.5 +/- 0.6 cm/sec, p = 0.003). The proximal segment of the sequential bypass graft has a higher velocity of blood flow than that seen in a single bypass graft. To obtain maximum hemodynamic advantage with the possibility of improving long-term patency rates, it is advisable to use the smaller coronary artery for the proximal sequential anastomosis.

Technical consideration in multiple valve and coronary artery surgery

Twelve patients at the University of Oregon Medical School Hospitals have undergone simultaneous double valve and aorto-coronary bypass graft operations. All were in Functional Class III or IV and most had angina pectoris. Nine patients had aortic and mitral valve replacement: Six patients had concomitant single aorto-coronary bypass grafts, 2 had concomitant double bypass grafts, and 1 patient had concomitant triple bypass grafting. The tenth patient had mitral valve re-replacement, tricuspid annuloplasty, and a single bypass graft. The eleventh patient had aortic valve replacement, mitral commissurotomy, and triple bypass grafting. The twelfth patient had aortic valve replacement, mitral commissurotomy, and single bypass grafting. The first 3 patients operated upon died 1, 6, and 19 days after the operation of acute myocardial infarction, low cardiac output, and related problems. The next 9 consecutive patients have survived operation. Five are in Functional Class I and 2 are in Functional Class II and free of angina 3 to 19 months later. The eighth patient is slowly improving after a prolonged, complicated hospital course. There was one late death at 6 weeks (arrhythmia). The improved survival rate is related to refinements in technique which expedite the procedure and allow maximum protection of the myocardium. Frequent intermittent coronary artery perfusion of the beating heart in conjunction with a systematic, modular approach to the procedure has allowed major cardiac reconstruction to be accomplished at low risks to the patient.