Comparison of patency of single and sequential radial artery grafting in coronary artery bypass.

OBJECTIVES: Sequential radial artery (RA) grafting has the potential to enhance arterial revascularization compared to single grafting. Sequential RA grafting was performed predominantly with a single side-to-side anastomosis. The study aimed to assess if sequential RA grafting improved long-term graft patency compared to single RA grafting. In addition, the anastomotic patencies of side-to-side and end-to-side anastomoses in sequential RA grafting were assessed. METHODS: Two hundred nineteen patients underwent isolated coronary artery bypass grafting with skeletonized RA conduits between 2005 and 2016. Of these, 208 patients underwent radiological graft assessment; thus, 125 and 83 patients underwent single and sequential RA grafting, respectively. The graft and anastomotic patency rates were estimated using the Kaplan-Meier method. RESULTS: The median follow-up period was 9.1 years, and the radiological assessment lasted 5.1 years. The overall RA graft patency rates at 1, 5 and 10 years were 99.4%, 92.7% and 88.1%, respectively. The RA graft patency rate for sequential grafting was similar to that for single grafting (88.7% vs 87.4% at 10 years; P = 0.88). In the stratified analysis of anastomotic patency, the patency rate of side-to-side anastomoses of sequential RA grafting was significantly better than that of end-to-side anastomoses (100% vs 88.7% at 10 years; P = 0.01). CONCLUSIONS: The long-term RA graft patencies of sequential and single grafting were equally high. The anastomotic patency of side-to-side anastomoses of sequential RA grafting was remarkably high. Considering these findings, the RA can be effectively used for multiple arterial coronary revascularizations.

Left atrial myxoma detected after an initial diagnosis of polymyalgia rheumatica.

We herein report the case of a 69-year-old woman with left atrial myxoma detected following treatment with glucocorticoids for an initial diagnosis of polymyalgia rheumatica (PMR). The glucocorticoids markedly improved the patient's symptoms, and the tumor was excised after rapidly tapering the glucocorticoid dose. The PMR-like symptoms did not recur and the inflammatory marker levels returned to normal after surgery. The patient's clinical course indicated that the initial PMR-like symptoms were entirely caused by the left atrial myxoma. This case demonstrates that glucocorticoid treatment for suspected PMR can mask the symptoms of myxoma, leading to a delay in diagnosis.

Reconstruction of the free margin of the anterior mitral leaflet with autologous pericardium in active infected endocarditis.

In patients with active infective endocarditis mitral valve repair is better than mitral valve replacement, but it remains a challenge when there has been massive destruction of the rough zone of the anterior leaflet. We report a technical modification of mitral valve repair for advanced active infective endocarditis in which a widely infected rough zone and the chordae were successfully replaced with autologous pericardium and multiple artificial chordae. The procedure described here is capable of improving the prospects of mitral valve repair in advanced infective endocarditis.

Apicoaortic valved conduit with an apical connector for aortic stenosis with a calcified aorta.

We report a case of apicoaortic bypass using an apical connector for severe aortic stenosis. A 74-year-old woman suffered from severe aortic stenosis, with a small aortic annulus and a severely calcified aorta. A valved conduit with an apical connector was placed between the left ventricular apex and the descending thoracic aorta because the risk of aortic valve replacement was high. Use of an apical connector facilitated a secure connection between the conduit and the left ventricular apex. The pressure gradient across the native aortic valve fell from 64 mm Hg before the operation to 19 mm Hg afterward. Apicoaortic bypass using the apical connector is a reliable option for relieving obstruction of the left ventricular outflow tract in the presence of aortic stenosis when aortic valve replacement is a high risk.

Comparison of active and passive coronary perfusion in off-pump coronary artery bypass grafting.

The myocardial protective effects of active and passive coronary perfusion were compared during off-pump coronary artery bypass grafting (OPCAB) in coronary stenosis model. An internal shunt tube was placed in the proximal left anterior descending arteries of adult dogs to produce a 75% coronary stenosis model. In 10 animals passive coronary perfusion was performed using an internal shunt tube placed in a pseudo-anastomotic site, and active coronary perfusion was performed through an external shunt tube. Ischemia was examined at normal and low blood pressure, based on hemodynamics, regional myocardial blood flow, and oxygen and lactate extraction in the perfused area. With passive perfusion, regional myocardial blood flow decreased and oxygen extraction and regional lactate production increased at normal blood pressure, indicating myocardial ischemia. Regional myocardial blood flow further decreased at low blood pressure. In contrast, regional myocardial blood flow with active perfusion did not change at normal or low blood pressure, and oxygen and lactate extraction were unchanged, indicating prevention of myocardial ischemia. Myocardial ischemia can occur with passive perfusion even at normal blood pressure. Active coronary perfusion that provides sufficient regional perfusion prevents myocardial ischemia during coronary artery anastomosis in OPCAB.

Aortic root re-replacement with cryopreserved aortic homograft in a patient with active composite valve-graft endocarditis.

We describe a repeat aortic root replacement using a cryopreserved aortic homograft in a patient with active composite valve-graft endocarditis and an aortic root abscess. At the second surgery, infected prosthetic material was removed and surrounding tissue was radically debrided. The cryopreserved aortic homograft was positioned using the full root technique with a concomitant coronary bypass graft. The postoperative course was uneventful and the patient continues to thrive 2 years after the repeat operation.

Cerebral perfusion using the tissue oxygenation index in mitral valve repair in a patient with porcelain aorta and aortic regurgitation.

We report successful mitral valve repair in a patient with porcelain aorta, complicated by aortic regurgitation, severe cerebrovascular disease, and multiple cerebral infarctions. The patient was a 77-year-old male who had congestive heart failure as a result of severe mitral regurgitation. Mitral valve repair was performed without aortic cross-clamping, using moderate hypothermic cardiopulmonary bypass. Aortic regurgitation was likely to worsen upon retracting the atrial septum to expose the mitral valve, complicating the operative procedure. We therefore controlled the regurgitation by lowering the blood temperature and using systemic perfusion flow. During systemic low-flow perfusion, we used near-infrared spectroscopy (NIRS) and the bispectral index to prevent cerebral hypoperfusion. The tissue oxygenation index value derived from NIRS was maintained above 55% during the procedure. The repair was performed safely with no difficulty. The postoperative course was satisfactory, with no neurological complications; echocardiography revealed no mitral regurgitation. The use of NIRS is valuable in preventing neurological complications in mitral valve operations complicated by porcelain aorta and aortic regurgitation.

Chondromodulin-I maintains cardiac valvular function by preventing angiogenesis.

The avascularity of cardiac valves is abrogated in several valvular heart diseases (VHDs). This study investigated the molecular mechanisms underlying valvular avascularity and its correlation with VHD. Chondromodulin-I, an antiangiogenic factor isolated from cartilage, is abundantly expressed in cardiac valves. Gene targeting of chondromodulin-I resulted in enhanced Vegf-A expression, angiogenesis, lipid deposition and calcification in the cardiac valves of aged mice. Echocardiography showed aortic valve thickening, calcification and turbulent flow, indicative of early changes in aortic stenosis. Conditioned medium obtained from cultured valvular interstitial cells strongly inhibited tube formation and mobilization of endothelial cells and induced their apoptosis; these effects were partially inhibited by chondromodulin-I small interfering RNA. In human VHD, including cases associated with infective endocarditis, rheumatic heart disease and atherosclerosis, VEGF-A expression, neovascularization and calcification were observed in areas of chondromodulin-I downregulation. These findings provide evidence that chondromodulin-I has a pivotal role in maintaining valvular normal function by preventing angiogenesis that may lead to VHD.

A surgical case of ventricular septal perforation after repairing left ventricular free wall rupture.

A 78-year-old woman with diagnosis of acute myocardial infarction (AMI) in the anteroseptal area fell into cardiogenic shock suddenly just before starting percutaneous coronary intervention (PCI). Echocardiography showed left ventricular free wall rupture, then an emergent operation was performed by sutureless patch repair using collagen fleece with fibrinogen-based impregnation. Eight days later from the initial operation, the onset of ventricular septal perforation (VSP) was recognized. Fifteen days after, the infarct exclusion technique with endocardial patch was performed. She has been doing well 4 months after the operation without residual shunt. To our best knowledge, this is the first surgical case report that free wall rupture of left ventricle and VSP which are serious complications after myocardial infarction happened in succession.

Resection of giant right atrial lymphoma using vacuum-assisted cardiopulmonary bypass without snaring the inferior vena cava.

A 53-year-old man sustained hemodynamic collapse due to a huge right atrial tumor and was transferred to our hospital and underwent a life-saving emergency operation. The tumor arose from the inferolateral wall of the right atrium, occupying almost the whole right atrial cavity and obstructing not only the inflow of the right ventricle but also the orifice of the inferior vena cava. Venous cannulation via the right atrial wall and placing a snare around the inferior vena cava were impossible. With a cardiopulmonary bypass using vacuum-assisted venous drainage, the tumor was successfully resected and the tricuspid valve was replaced with a bioprosthetic valve without snaring the inferior vena cava. Postoperative histological examination demonstrated the tumor to be a large B-cell non-Hodgkin type malignant lymphoma. When the tumor is large and it is difficult to establish total cardiopulmonary bypass, the vacuum-assisted cardiopulmonary bypass is a useful option. This can achieve a bloodless operative field and is not blocked by the incoming air, due to the venous drainage being continually pressure-regulated.

Active distal coronary perfusion to prevent regional myocardial ischemia in off-pump coronary artery bypass grafting.

Regional myocardial ischemia during anastomosis in off-pump coronary artery bypass (OPCAB) can occasionally cause hemodynamic instability. To prevent regional myocardial ischemia and stabilize the hemodynamics during the procedure, perfusion of the distal coronary artery to the anastomotic site is necessary as the only reliable method. We have applied an active coronary perfusion method using a servo-controlled pump in selected patients in place of conventional passive perfusion methods (intraluminal shunt and external shunt). We present a case in which the active perfusion method proved useful in avoiding regional myocardial ischemia. A 74-year-old male patient with triple-vessel coronary disease underwent OPCAB for unstable angina. During revascularization of the main right coronary artery, the hemodynamics collapsed due to regional myocardial ischemia. As soon as the distal coronary artery was perfused at a high flow rate around 80 ml/min, the hemodynamics stabilized and the operation was completed successfully. This active coronary perfusion method in OPCAB is particularly useful in cases in which regional myocardial ischemia cause hemodynamic instability.

Ventricular septal rupture masquerading as coronary perforation during intervention for acute myocardial infarction.

Ventricular septal rupture is a serious complication of acute myocardial infarction. We experienced a case of septal rupture immediately after primary angioplasty with thrombolysis, whose angiographic findings were similar to those of coronary perforation. The progression of septal rupture was delineated by the serial angiograms.

Surgery for advanced gastric cancer after coronary artery bypass grafting using the right gastroepiploic artery: report of a case.

Ischemic heart disorders are often treated by coronary artery bypass grafting (CABG) using the right gastroepiploic artery (RGEA). We report the case of a 57-year-old man with a history of CABG using the RGEA, who underwent D2 radical total gastrectomy followed by Roux-en-Y anastomosis, with successful dissection of the #6 lymph nodes, while preserving the RGEA. The patient had a 9-month history of gastric cancer, during which time the Maruyama Vaccine (Specific Substance Maruyama, or SSM) was given as alternative therapy. This case report serves to demonstrate that radical gastrectomy can be safely performed after CABG using the RGEA, and that gastric cancer will progress in spite of SSM therapy.

Changes in left ventricular volume and predictors of cardiac events after endoventricular circular patch plasty.

OBJECTIVE: The aim of this study was to identify predictors of cardiac events after endoventricular circular patch plasty (Dor operation) by analyzing our experience with Dor operation. METHODS: Thirty patients with left ventricular aneurysm and/or ischemic cardiomyopathy who underwent Dor operation were included in this study. Hemodynamic and clinical results were analyzed, and the predictors of cardiac events were examined. RESULTS: Hospital mortality was 3.3%. Postoperative clinical status and left ventricular (LV) function in all survivors significantly improved. The survival rates at 1, 3, and 5 years after operation were 93%, 89% and 89%. The corresponding cardiac event-free rates were 75%, 67% and 49%. Pre- and postoperative LV function and volume did not differ significantly between patients with or without cardiac events. However, the proportion of reduced end-diastolic volume index (EDVI) (preoperative EDVI-postoperative EDVI) to preoperative EDVI was significantly higher in patients with cardiac events than in cardiac event-free patients. Postoperative LV volume re-increased in the cases with cardiac events during follow-up. Cox regression analysis confirmed that preoperative clinical premature ventricular contraction and end-systolic volume index (ESVI), postoperative EDVI, ESVI, and ejection fraction were independent predictors of late cardiac events. There was a significant positive correlation between preoperative ESVI and postoperative EDVI. CONCLUSION: Though LV function significantly improved after Dor operation, LV reconstruction with excessive reduction can cause restarting LV remodeling and increasing mortality and morbidity. Therefore, LV reconstruction of appropriate sizes and shapes, considering the function of residual myocardium, has a significant effect on prognosis. It is highly reasonable to expect that preoperative ESVI can predict the optimal size of reconstructed left ventricle.

Mortality and morbidity after total arch replacement using a branched arch graft with selective antegrade cerebral perfusion.

BACKGROUND: The early outcome after aortic arch surgery has improved. However, some operative survivors have died as a result of postoperative problems soon after discharge. This study determines the factors affecting mortality within 1 year of total arch replacement. METHODS: Between July 1993 and November 2001, 103 patients (mean age 65 +/- 11 years, 26 women, 35 dissections) underwent total arch replacement through a median sternotomy using a branched arch graft with selective cerebral perfusion. Eighteen operations including 14 acute dissections were performed on an emergency basis. Concomitant procedures were root replacement in 5 patients, mitral valve replacement in 1, coronary artery bypass in 14, and open endovascular stent-graft in 9. The average time (minutes) for bypass, aortic cross-clamp, selective cerebral perfusion, and distal arrest were respectively 273 +/- 79, 163 +/- 54, 145 +/- 36, and 69 +/- 22. RESULTS: Mechanical heart support was necessary in 3 patients. Stroke occurred in 9 patients, transient neurologic dysfunction in 7, and paraplegia/paraparesis in 4. The only independent determinant for postoperative stroke was a history of stroke (odds ratio 16.3, 95% confidence interval: 2.8 to 93.8). Thirty-one patients required ventilator support for more than 5 days. Hemodialysis was needed in 5 patients. Sternal infection or mediastinitis occurred in 6 patients. The in-hospital mortality was 12% (12 of 103). The actuarial survival rate at 1 year was 83%, and was 67% at 5 years. For the 1-year mortality independent determinants were emergency surgery (odds ratio 5.3, 95% confidence interval: 1.6 to 17.9) and age 75 years or older (odds ratio 4.0, 95% confidence interval: 1.1 to 13.9). CONCLUSIONS: Total arch replacement using a branched arch graft with selective antegrade cerebral perfusion has a favorable 1-year mortality rate except for patients undergoing emergency surgery and for elderly patients.

A case in which biventricular assist device support was required after aortic valve replacement with a bioprosthetic valve.

We report the case of a 45-year-old man with severe aortic regurgitation. The patient underwent aortic valve replacement with a bioprosthetic valve, but was unable to be weaned from cardiopulmonary bypass (CPB). Intraoperative coronary angiography revealed stenosis of the right coronary orifice, so an intra-aortic balloon pump was inserted and coronary artery bypass grafting to the right coronary artery was conducted; however, weaning from CPB again failed. Left ventricular assist using a Gyro centrifugal pump was performed between the left atrium and left femoral artery, along with right ventricular assist using a Nikkiso centrifugal pump between the right atrium and pulmonary artery. Flow rates averaged from 2.0 to 2.8 l/min for the left-side ventricular assist device (VAD) and 2.1-3.8 l/min for the right-side VAD. The bypass rate reached approximately 70% at maximum. No thromboembolic events were documented during VAD support. The patient underwent explantation of VADs on postoperative day 4. No thrombus was identified on the bioprosthetic aortic valve by transesophageal echocardiography. The left-side pump displayed no thrombus, while the right-side pump had a small thrombus at the shaft. The patient was discharged from the hospital and was alive as of 2 year postoperatively. To the best of our knowledge, no clinical study has yet compared the antithrombotic properties of two centrifugal pumps in one patient where mechanical support was performed for the same duration and flow rate.

Comparison of early postoperative quality of life in minimally invasive versus conventional valve surgery.

PURPOSE: Minimally invasive cardiac surgery (MICS), an approach in which full sternotomy is avoided and the surgical incision is minimal, has been shown to produce less postoperative discomfort and to enable earlier mobilization and discharge than conventional cardiac surgery (CCS). This study was performed to retrospectively evaluate quality of life following MICS in comparison with CCS valve surgery. METHODS: Sixty-six patients scheduled for MICS and 50 patients scheduled for CCS for isolated aortic or mitral valve surgery from January 1999 to June 2001 were enrolled in the study. The clinical records for the two groups were compared across intraoperative parameters and those associated with postoperative quality of life. RESULTS: The aortic clamp and cardiopulmonary bypass times in the MICS group were longer than those in the CCS group (144 +/- 42 and 224 +/- 58min vs 112 +/- 21 and 179 +/- 27min, P < 0.001). Postoperative pain medication (rectal buprenorphine and intramuscular pethidine) was administered to 18 of the 66 MICS patients (27%), as compared with 26 of the 50 CCS patients (52%, P = 0.007). Postoperative delirium was less frequent in the MICS group than the CCS group (26% vs 44%, P = 0.039). Initial postoperative food intake and urine catheter removal were possible earlier in the MICS than in the CCS group. MICS patients had shorter stays in the intensive care unit than CCS patients (37.4 +/- 7.3 vs 45.9 +/- 8.7h, P < 0.001). CONCLUSION: Although longer aortic clamp and cardiopulmonary bypass times remain a problem in MICS procedures, our results suggest that MICS, as compared with CCS, facilitates earlier recovery of daily activities and provides improved quality of life in the early postoperative period.

Effects of atrial fibrillation on coronary artery bypass graft flow.

OBJECTIVES: No detailed studies exist of coronary artery bypass graft flow during atrial fibrillation. We examined the effects on bypass graft flow of atrial fibrillation following coronary artery bypass grafting. METHODS: Immediately after surgical revisualization, atrial fibrillation was induced in 18 patients by high frequency atrial pacing. Hemodynamic variables were measured in sinus rhythm and atrial fibrillation. The graft flow in pedicled left internal thoracic artery grafts and in saphenous vein grafts was also measured using transit-time flowmetry. RESULTS: Left internal thoracic artery graft flow had a greater diastolic component than saphenous vein graft flow, as shown by the percent diastolic time-flow integral (86 +/- 10% in the left thoracic artery and 62 +/- 12% in the saphenous vein, P < 0.0001). The induced atrial fibrillation caused significant deterioration in hemodynamics: heart rate and central venous pressure increased, and mean arterial pressure and cardiac index decreased (all P < 0.0025). In left internal thoracic artery grafts (n = 18) and also in saphenous vein grafts (n = 20), graft flow decreased significantly with atrial fibrillation (44.3 +/- 26.2 to 26.2 +/- 20.7 ml/min in the left internal thoracic artery, P = 0.0003; 39.7 +/- 15.6 to 33.3 +/- 14.3 ml/min in the saphenous vein, P = 0.001). The reduction in graft flow due to atrial fibrillation was much larger in left internal thoracic artery grafts than in saphenous vein grafts (P = 0.0008). CONCLUSIONS: Direct measurement of coronary artery bypass graft flow shows that atrial fibrillation after surgery significantly reduces graft flow. The effect is much larger in left internal thoracic artery grafts with their strong diastolic component than in saphenous vein grafts.

Minimally invasive cardiac surgery by the port-access method.

Recently, minimally invasive surgery has come to be an important theory in cardiac surgery, the goal of which is shortening of hospital stay, earlier recovery of employment, and cosmetics. In this paper, we will describe our experience with port-access cardiac surgery conducted under the support of our new technology. This study assesses the quality of cardiac surgery performed by the port-access method. The author developed a direct endoaortic clamp balloon (Yozu balloon). This balloon is a triple-lumen balloon catheter of 3.6 mm in outer diameter and 40 cm in full length. The balloon is inserted directly into the ascending aorta. Injection of cardioplegic solution and aortic vent can be conducted. Also, we introduce a modified Cosgrove flex clamp to apply in small-incision surgery, aiming at a less invasive procedure. The modified point is that the original, united Cosgrove flex clamp can be divided into the handle part equipped with a ratchet, and the bellows part equipped with a clamp jaw. By this modification, it became possible to apply the Cosgrove flex clamp transthoracically; that is, it became possible to conduct aortic clamping safely and securely through this small port of 8 mm in diameter. Port-access cardiac surgery is one of the developing and promising methods of cardiac operation. In view of future technological progress, we can expect the gradual but wide popularization of this method.