Endoscopic radial artery harvesting for coronary artery bypass grafting: the initial clinical experience and results of the first 50 patients.

BACKGROUND: The radial artery (RA) is a commonly used arterial conduit in coronary artery bypass grafting (CABG). Traditional open-vessel harvest often leads to postoperative wound complications and cosmetic problems. Endoscopic RA harvesting (ERAH) has been widely used to prevent these problems. The purpose of this study was to assess these problems and graft patency in the first 50 patients who underwent ERAH. METHODS: Between February 2006 and October 2007, 50 patients underwent ERAH with the VasoView system (Boston Scientific). These patients were compared with 50 patients who underwent the traditional open technique. RESULTS: The mean age was 62.8 years in both groups. All RAs were successfully harvested. No conversion was made from ERAH to the traditional open technique. The mean harvesting time (forearm ischemic time) was 27.4 + or - 6.5 minutes, and the mean length of the RA in the ERAH group was 18.5 cm. Neither wound complications, such as wound infection and skin necrosis, nor severe neurologic complications were recorded. The patency rate was 95.9% (95/99) in the ERAH group and 94% (94/100) in the open group. CONCLUSION: ERAH can be performed safely, and the early results are satisfactory. Endoscopic vessel harvesting is therefore recommended as the technique of choice for RA harvesting.

[Aprotinin reduces bleeding during off-pump coronary artery bypass grafting in a patient on ticlopidine; report of a case].

A 65-year-old man was admitted to a local hospital with symptoms of unstable angina pectoris. He was administered ticlopidine before drug eluting stent (DES) stenting for 2 weeks. Coronary angiography showed 3 vessel diseases. He was then admitted to our hospital due to a sudden onset of unstable angina following shock during the percutaneous coronary intervention (PCI) procedure, emergency off-pump coronary artery bypass grafting (OPCAB) was thus performed. He received aprotinin 5 hundred thousand KIU just at the start of surgery and 5 hundred thousand KIU after undergoing anastomosis of the coronary artery. Postoperatively, only some minor bleeding was observed. Aprotinin reduces bleeding, the transfusion requirements of packed red blood cells, platelets, and the total blood units in patients on ticlopidine who undergo emergency OPCAB.

New method of thermal coronary angiography for intraoperative patency control in off-pump and on-pump coronary artery bypass grafting.

BACKGROUND: We evaluated the effectiveness of a new thermal coronary angiogram system using intraoperative imaging with an infrared camera for coronary artery bypass grafting. METHODS: The thermal coronary angiograms of 51 patients who underwent a total of 107 coronary artery bypass grafts were evaluated. Thermal coronary angiograms were obtained after completing distal anastomoses by the injection of cold saline solution into the vein grafts or free arterial grafts or by reperfusion with warmer blood in the internal thoracic artery grafts. Temperature differences of greater than 0.1 degrees C between the injectant and the epimyocardium resulted in high-contrast images. RESULTS: Thermal coronary angiograms were obtained from 107 coronary artery bypass grafts; 103 grafts were patent (96.3%), and 2 internal thoracic artery grafts were occluded. After reanastomoses, thermal coronary angiograms were again obtained, and all grafts appeared to be patent. Four grafts did not clearly show hemokinesis because of an intramyocardial segment or circumferential fat surrounding the artery. CONCLUSIONS: Thermal coronary angiograms cannot show hemokinesis clearly in cases with an intramyocardial arterial segment or in patients in whom the grafts are surrounded by fat. Therefore, thermal coronary angiograms are considered to play a valuable role in confirming the success or failure of myocardium revascularization because this diagnostic modality does not interfere with the surgical procedures, is noninvasive, and can be both quickly and easily performed.

Coronary artery bypass grafting in DES era.

Coronary artery bypass grafting (CABG) has played an important role in the treatment of ischemic heart disease. Recently, the introduction of a drug-eluting stent (DES) has decreased the incidence of restenosis after percutaneous intervention (PCI). PCI with a DES is being increasingly performed, whereas the number of patients for whom CABG has been indicated has decreased over the last few years in Japan and the United States. According to a report, the number of patients undergoing CABG will not decrease in the future due to its usefulness in the treatment of multi-vessel lesions. We have also reviewed how CABG should be improved. For this purpose, it may be important to carry out less invasive CABG by the off-pump method and to improve the long-term results obtained by CABG with an internal thoracic artery graft and complete revascularization. Hence, CABG may achieve better long-term results compared with PCI and continued future application of CABG.

Application of a new suture material called the U-Clip for composite and sequential grafting with off-pump coronary bypass surgery.

BACKGROUND: The U-Clip was found to facilitate the interrupted anastomosis of coronary artery bypass grafts (CABG). This device may be beneficial especially in multivessel off-pump CABG (OPCAB) using composite grafts or sequential anastomosis. The aim of this study was to evaluate our early clinical experience using the U-Clip in OPCAB cases. METHODS: This retrospective study included 118 patients who underwent off-pump CABG between 2001 and 2004. The mean age of the 91 men and 27 women was 69.5 +/- 8.0 years (range, 47-85). The U-Clip was adopted for sewing 73 proximal ends of the free graft to the side or end of the inflow conduit to prepare the composite graft. The U-Clip was also applied to 112 distal anastomoses, especially to the side-to-side anastomosis of the sequential graft. RESULTS: Hospital mortality rate was 0.8% (1/118). The early patency rate of distal anastomoses using the U-Clip was 95% (96/101). The early patency rate of proximal anastomoses using the U-Clip was 98.4% (62/63). Interim angiography was performed in 12 patients (range, 3.8-42 months; average, 16 months). In these 12 patients, a total of 8 proximal anastomoses of conduits using the U-Clip were all patent without stenosis. The patency rate of a total of 10 distal anastomoses in the 12 patients using the U-Clip was 100%. CONCLUSIONS: The U-Clip-interrupted anastomosis enables a safe, definite, and rapid end-to-end or end-to-side connection of arterial grafts. We therefore consider the U-Clip to be a useful suture material especially for multivessel OPCAB using multiple arterial grafts.

Central arterial cannulation and the arch first method for aortic arch aneurysm repair.

BACKGROUND: We investigated whether the axillary artery or ascending aorta cannulation combined with the arch first method decreases the risk of stroke during total arch replacement. PATIENTS AND METHODS: From January 2002 to January 2006, 35 total arch replacements were performed with the arch first method and central arterial cannulation. The mean age was 66+/-10 years. The cannulation sites were the axillary artery in 19 and the ascending aorta in 16. The arch first method (a short period of deep hypothermic circulatory arrest with retrograde cerebral perfusion and then subsequent antegrade cerebral perfusion) was used in all patients. RESULTS: The mean retrograde cerebral perfusion time was 29+/-7 min. The incidence of the permanent neurological dysfunction related to the surgical procedures was 2.9% (1/35). Hospital mortality was 5.7% of patients (2/35). There was no difference in the operative outcome between the 2 arterial inflow sites. CONCLUSION: At the time of total arch replacement, the use of central arterial cannulation and the arch first method are effective methods for preventing permanent brain injury. Cannulation of the ascending aortic using Dispersion cannula perfusing toward the aortic valve is considered to be a safe and favorable method for central arterial cannulation.

Development of the oxygenator: past, present, and future.

From the 1950s to the 1980s, the most widely used oxygenator in the clinical field was the disposable bubble oxygenator. However, membrane oxygenators have become the preferred clinical choice over the years. In the United States, membrane oxygenators used in cardiopulmonary bypass operations account for the majority of clinical oxygenator use. Membrane oxygenators have an equal capability for oxygenating venous blood compared with other type of oxygenators such as the bubble type and film type; however, the membrane oxygenator requires a smaller volume for priming to achieve a sufficient gas transfer rate and results in less blood trauma such as hemolysis because it uses a similar mechanism to the natural lung. In the 1980s, the first capillary-type oxygenator adopted the system of intracapillary blood perfusion. However, this induced high pressure resistance in the module and caused hemolysis. Thus, at present, capillary oxygenators commonly adopt the system of extracapillary blood perfusion. Microporous hollow-fiber membranes are primarily used for short-term cardiopulmonary bypass application, whereas nonmicroporous hollow-fiber membranes are primarily used for long-term extracorporeal membrane oxgenation application.

Development of implantable right ventricular assist device.

Implantable ventricular assist devices (VADs) are indicated for long waiting periods before transplantation and also as a destination therapy. Meanwhile, right ventricular failure (RVF) is one of the four major complications observed in patients after left VAD (LVAD) implantation, with an incidence of approximately 20%. Preoperative prediction of the complication remains difficult, and the mortality is very high. To date, no implantable right VAD (RVAD) is available for the clinical situation. The possibility of realizing an implantable RVAD with Gyro centrifugal pump (PI-710 pump) was investigated. Eleven chronic animal experiments with LVAD and RVAD implantation were performed. Right heart bypass was established between right outflow and pulmonary trunk, and the pump was implanted in the preperitoneal space. The anatomic fit was good. The mean term of the experiments was 59 days, with excellent pump performance. Stable pulmonary hemodynamics and respiratory function were maintained during all of the experimental terms. No specific abnormal histologic findings of the lung were confirmed; however, tunica media hypertrophy was recognized in some cases. The PI-710 pump is feasible as a clinically implantable RVAD, but further study of histologic and pulmonary vascular changes after RVAD implantation is needed.

Commissural dehiscence and pannus formation of porcine heart valve bioprostheses.

From May 1976 to June 2001, 95 porcine heart valve bioprostheses (BPs) were explanted. Among them, 85 prostheses were available for an analysis of structural valve deterioration (SVD). There were 32 Hancock (H) BPs and 53 Carpentier-Edwards (CE) BPs, with a mean implantation duration of 12 +/- 3.5 and 11.0 +/- 4 years, respectively. There were two extraordinary complications. One was commissural dehiscence (CD) of the CEBPs in 10/53 cases (18.9%), with a mean duration of 12.7 +/- 2.7 years. This was not observed in the HBPs. The other was pannus formation in both BPs. In the mitral position, it was 25/32 (78.1%) in HBPs and 37/53 (69.8%) in CEBPs. In the aortic position, it was 4/32 (1.3%) in the HBPs and 11/53 (20.8%) in the CEBPs. We conclude that CD could not be diagnosed preoperatively and anticoagulation is therefore indicated to prevent pannus formation of such prostheses, particularly in those located in the mitral position.

Off-pump coronary artery bypass grafting in patients with end-stage renal disease on hemodialysis.

BACKGROUND: Coronary artery bypass grafting (CABG) for hemodialysis patients is high risk compared with other patient groups. The aim of this study was to analyze the potential benefits of off-pump CABG for hemodialysis patients. METHODS: From April 1994 through December 2000, 26 hemodialysis patients underwent CABG. The off-pump group consisted of 15 patients operated on without a pump and the on-pump group consisted of 11 patients operated on with a pump. RESULTS: There was no difference between the two groups with regard to mean age, mean number of diseased vessels and mean number of anastomoses per patient. No patient died in either group during hospitalization. The postoperative complication rate was low in both groups. The postoperative ventilation time was shorter in the off-pump group (8.5 vs 26.1 hours, p < 0.001, respectively [off-pump group vs on-pump group]). The length of ICU stay was shorter in the off-pump group (1.7 vs 3.5 days, p = 0.01, respectively [off-pump group vs on-pump group]). The medial cost was lower in the off-pump group (26,200.80 dollars versus 44,024.10 dollars p = 0.0001 respectively [off-pump group vs on-pump group]). CONCLUSIONS: Off-pump CABG provided excellent less-invasive cardiac surgical results for dialysis patients.