Histological evaluation of skeletonized internal thoracic artery using ForceTriad™.

BACKGROUND: The internal thoracic artery (ITA) is a useful graft for coronary artery bypass grafting. Skeletonization, a technique that uses an ultrasonic scalpel, is increasingly used. However, the cost of an ultrasonic scalpel is extremely high. The purpose of this study was to determine whether a new electrosurgical cautery device (ForceTriad™) is as effective as an ultrasonic scalpel. METHODS: Bilateral ITAs were harvested from eight pigs using the skeletonizing technique. The ITA on one side was harvested with an ultrasonic scalpel and on the other side using the ForceTriad™. Macroscopic and histological examinations were performed in sixteen ITAs. RESULTS: No significant differences in the time required for harvesting were observed. The macroscopic findings revealed no significant change in any of the samples. The histological findings showed that the degree of thermal injury was similar. The normal structure was maintained in all samples. The ForceTriad™ costs US$ 226.82 less per patient than the ultrasonic scalpel. CONCLUSION: The new electrosurgical cautery device ForceTriad™ was less expensive, but it was equally effective. It appears that skeletonization performed with the new device is equivalent to that performed with an ultrasonic scalpel.

Obstruction of St Jude Medical valves in the aortic position: significance of a combination of cineradiography and echocardiography.

BACKGROUND: Obstruction of the St Jude Medical valve (St Jude Medical, Inc, St Paul, Minn) is a rare but serious complication. METHODS: Cineradiographic and echocardiographic evaluations of aortic St Jude Medical valves were simultaneously performed on 54 patients, with no signs of prosthetic valve dysfunction late after surgery. RESULTS: Although closing angles of the leaflets corresponded closely with the manufacturer data, restricted opening of the leaflets (opening angle >/= 20 degrees ) was found in 16 (group D) of the 54 patients by means of cineradiography. The opening angles were equal to or less than 14 degrees in the other 23 patients (group N) and between 15 degrees and 19 degrees in the remaining 15 (group M). Doppler-derived transprosthetic pressure gradients were significantly higher (P =.03) and the velocity index was significantly lower (P =.003) in group D than in group N. However, no significant differences were found in those values between group N and group M. Replacement of the aortic St Jude Medical valves was performed in 5 of the 16 patients, and the remaining 11 have been followed up because of relatively low pressure gradients. The cause of restricted leaflet movement was pannus formation without thrombosis in 4 patients and valve thrombosis with pannus formation in one. CONCLUSIONS: Reduced valve orifice area and restricted opening of the leaflets resulting from excess growth of pannus probably led to obstruction of the aortic St Jude Medical valves. A combination of cineradiography and echocardiography makes it possible to provide an accurate and detailed diagnosis of obstruction of the valve.

Long-term follow-up results after reconstruction of the mitral valve by leaflet advancement.

In this study, we discuss the clinical results of mitral leaflet advancement performed on 29 patients over the past 10 years and attempt to determine the indication. Preoperative diagnosis of mitral valve lesion consisted of mitral regurgitation in 21 patients and mitral stenosis in 8 patients. Mitral valve repair was applied to the anterior mitral leaflet in 2, the posterior mitral leaflet in 25, and bilateral leaflets in 2 patients. Reoperation was performed on 13 patients, and 1 patient died of renal failure immediately after reoperation. No reoperation was needed for 96.6% of the patients at 1 year, 89.5% at 5 years, 75.0% at 8 years, 63.8% at 10 years, and 52.6% at 15 years postoperatively. At reoperation, the repaired mitral leaflet was found to be calcified in 3 patients more than 9 years after the initial operation. Of the 12 survivors without reoperation, mitral stenosis associated with regurgitation was obvious in 6 patients. Of the 21 patients with preoperative mitral regurgitation, 90.0% showed no deterioration at 5 years, 79.7% at 8 years, and 69.1% at 10 years. On the other hand, for the 8 patients with mitral stenosis, the rates were 87.5% at 1 year, 62.5% at 5 years, 50.0% at 8 years, and 25% at 10 years. Our results suggest that mitral leaflet advancement shows satisfactory results in patients with mitral regurgitation but is not successful for patients with mitral stenosis in the long term because the repaired valve tends to be stenotic in the late postoperative period.

Right atrial thrombus associated with combined valvular disease: case report.

A 77-year-old man had a large right atrial (RA) thrombus associated with a combined mitral and tricuspid valve disease. Echocardiography showed a large, immobile, non-homogeneous, irregularly surfaced mass in the dilated RA, and prolapse of the anterior mitral leaflet resulting in massive mitral regurgitation. Computed tomography (CT) revealed a laminated structure with calcification and distinct margins, without invasion to the wall of the RA. On the basis of these echocardiographic and CT findings, a diagnosis of combined mitral and tricuspid valvular disease complicated with RA thrombus was made. Removal of the RA thrombus, mitral valve replacement and tricuspid annuloplasty were performed simultaneously, with successful outcome.

Improvement of postoperative graft patency rate for coronary revascularization.

For coronary artery revascularization, the long term patency rate of internal thoracic artery (ITA) is excellent and arterial conduit for coronary bypass grafting (CABG) has been actively pursued. Application of the right gastroepiploic artery (GEA) is on the increase but, the patency of the GEA graft is more technically demanding than that of ITA. To improve early postoperative graft patency for coronary artery bypass grafting (CABG) for arterial graft, we modified the technique for anastomosis and demonstrated the patency by postoperative angiogram in 26 consecutive patients receiving CABG. The graft was anastomosed to the coronary artery using two 8-0. Prolene sutures for arterial graft and 7-0 Prolene sutures for saphenous vein (SV) graft. The heal and toe sides of the graft were sutured separately by the parachute technique (double parachute technique), followed by running suturing and typing at bilateral sides. The number of distal anastomoses was 3.4/patient and 44 arterial grafts and 40 SV grafts were used for coronary revascularization. Arterial grafts consisted of 33 ITAs, 9 GEAs, and two inferior epigastric arteries. The angiograms taken 10 to 14 days after operation demonstrated 100% patency rate of arterial grafts and 39 out of 40 SV grafts were patent. The overall patency rate in the early postoperative period was 98.8% The "double parachute" technique for CABG is highly accurate anastomosis with good visualization and the patency rates for all kinds of grafts were found to have improved.

Successful removal of an infected pacemaker electrode by open heart surgery under extracorporeal circulation.

A 33-year-old male with sick sinus syndrome, who had received a pacemaker implant 18 years earlier, was complicated with a generator infection. Although the infected generator was removed, he was suffered from the recurrent local infection associated with a retained pacemaker lead. After a new pacemaker system implantation from the other side of the subclavian vein, we attempted to remove the lead utilizing a pacemaker removal kit. However, this intervention procedure was unsuccessful, because fibrous adhesions had developed around the lead, accompanied by calcification along its course. As a last resort, we opened the heart under extracorporeal circulation and removed the lead under direct vision. The post-operative course was uneventful. In order to remove a long-term implanted pacemaker lead, the direct surgical procedure with extracorporeal circulation is a favorable mean alternative to conventional intervention techniques.

Ultrastructural alterations of right and left ventricular myocytes in tetralogy of Fallot.

We examined the ultrastructure of right and left ventricular myocardial biopsies obtained prior to cardiopulmonary bypass in fourteen patients undergoing total correction of tetralogy of Fallot (TOF). Twelve patients were undergoing primary one-stage repair and two patients had had a previous Blalock-Taussig shunt operation. The ages of the patients ranged from 3 to 35 years. In left ventricular (LV) myocytes, the sarcolemma often formed pouches filled with mitochondria and the muscle fibers showed a disoriented arrangement. In addition, the myofibrils showed hypercontraction and the Z-bands were thickened; the degree of the myofibril contraction was more severe than that in right ventricular (RV) myocytes. These ultrastructural findings are similar to those observed in myocytes under hypoxic conditions. The number of lysosomes in LV myocytes, but not in RV myocyte increased in the older patients. While we have not established a causal relationship between the ultrastructural findings and clinical features in our cases, our observations are consistent with the possibility that early total correction of TOF may be required to prevent the development of hypoxic changes and degeneration of heart muscle.

An evaluation of long-term results over 10 years after intracardiac repair of tetralogy of Fallot.

A follow-up study was conducted of 166 patients who had survived for more than 10 years after total correction of tetralogy of Fallot. The total number of patients in NYHA class I was 141 (85%); the other 25 patients had been medically treated or had followed a prudent life style. The factors which caused postoperative symptoms were residual lesions and ventricular arrhythmia. Ultrasonic echocardiography showed that among 72 patients with transannular patch, 68 (95%) showed moderate or severe pulmonary incompetence. There was a correlation of gamma = 0.43 between the severity of pulmonary incompetence and cardiothoracic ratio in the 48 patients without any residual lesions, while two cases with severe pulmonary incompetence showed obvious right ventricular failure. Ambulatory ECG monitoring was employed to study 53 patients. As a result, 21 patients were found to present solitary moderate or severe pulmonary incompetence, while premature ventricular contraction of Lown's grade 4A was seen in nine patients (42.9%). In conclusion, it is considered essential to carefully follow up patients after intracardiac repair of tetralogy of Fallot, especially those with severe pulmonary incompetence.

Risk factors for posttransfusion graft versus host disease, mediastinitis, and late cardiac tamponade in heart surgery. Survey of 119 Japanese institutions.

OBJECTIVE: Correlations and risk factors remain to be unclarified for post-heart-surgery posttransfusion graft-versus-host disease, mediastinitis, and late cardiac tamponade caused by deteriorated host-defense mechanisms due to cardiopulmonary bypass both with and without steroid usage. METHODS: We sent questionnaires to 298 Japanese cardiovascular institutions asking for institution profiles, including infection control, steroid use in cardiopulmonary bypass, and prevalence of mediastinitis, late cardiac tamponade, and posttransfusion graft-versus-host disease during 1994. The overall prevalence of posttransfusion graft-versus-host disease since the start of service (from establishment of institution to date) was also requested. RESULTS: The number of pump cases at the 119 institutions responding (40%) were 91.6 +/- 67.9 cases/institution (total = 10,904). The prevalence of mediastinitis was 1.2 +/- 1.8 and that of late cardiac tamponade 1.0 +/- 1.8%. Posttransfusion graft-versus-host disease occurred in 1 of 10,904 patients (0.01%) during 1994 at an institution where steroids and nonirradiated blood were used in surgery. The simple institutional mean prevalence of posttransfusion graft-versus-host disease since establishing institutions was 0.08 +/- 0.13%. Of the 119 institutions surveyed, 86 used steroids in all pump cases (72%); 11 institutions used steroids in a limited number of cases (9%). The institutional mean of methylprednisolone-converted steroid dose was 21.5 +/- 16.4 mg/kg (n = 119). In multivariate regression analysis, operation time (p = 0.005) for mediastinitis, steroid usage (all, limited, or no cases) (p = 0.01) and % aneurysm (p = 0.05) for late cardiac tamponade, and steroid dosage (p = 0.002) for posttransfusion graft-versus-host disease were identified as significant risk factors. CONCLUSION: Our results suggest that massive steroid administration for cardiopulmonary bypass may increase the risk of posttransfusion graft-versus-host disease and late cardiac tamponade, but not mediastinitis.

[Multiple systemic embolization from floating thrombus in left atrium].

A 66-year-old woman was referred to our hospital because of cerebral infarction, myocardial infarction and renal infarction. Further examination indicated that she was suffering from mitral valve stenosis with a floating thrombus in the left atrium. She underwent emergency mitral valve replacement and thrombectomy. The thrombus was attached to the left atrium by only four thin and weak strings and removed easily. We think that the thrombus was the precursor of a free-floating ball thrombus without stalk.

[Reoperative coronary revascularization without cardiopulmonary bypass].

We report a case of successful reoperation of coronary revascularization without cardiopulmonary bypass. The patient was a 62-year-old man, who had undergone coronary artery bypass grafting (CABG) to the LAD and CX with two saphenous vein grafts (SVG) for the left main lesion 12 years before. He required reoperation for unstable angina due to progressive ischemic heart disease and the diseased SVG. Preoperative coronary angiogram revealed total occlusion of major 3 branches and the diseased SVG to the LAD. The reoperation was performed without cardiopulmonary bypass through the repeated median sternotomy for revascularization of the LAD and RCA. The left internal thoracic artery and the gastroepiploic artery were anastomosed to the LAD and RCA under the beating heart without any hemodynamic or electrocardiographic deteriorations. The operation was uneventfully finished in 3 hr 40 min. without the use of blood products. Postoperative angiogram showed both new grafts were widely patent, and he was discharged 14 days after the operation without angina. We also performed 4 other cases of reoperative CABG without cardiopulmonary bypass, and conclude that this technique is a safe and effective alternative in a carefully selected group of patients for reoperative CABG to reduce several technical problems related to coronary reoperation.

[Coronary artery bypass grafting: does the use of arterial graft for coronary artery bypass grafting increase surgical risk?].

Since April in 1988 coronary artery bypass grafting (CABG) was performed in 177 patients and the clinical results were compared in SVG-group (n = 37) in which only saphenous vein graft (SVG) was used as a graft conduit and AG-group in which one arterial graft (AG-1 group, n = 92) or more than two arterial grafts were used (AG-2 group, n = 48). In SVG-group the age was older than that in AG-group, while coronary vessels were most involved in AG-2 group and the mean number of distal anastomosis increased more in AG-group. The total pump time and aortic cross clamping time showed no significant differences among the groups. Furthermore, the occurrence of perioperative myocardial infarction, requirement of intra-aortic balloon pumping, frequency of re-chest open for hemorrhage, or sternal infection showed no significant differences among the groups. Postoperative hospital deaths were in four (three cardiac deaths) of SVG-group and four (one cardiac and two graft-versus-host disease) of AG-group. These results suggest that the use of AG does not increase surgical risk and AG can be positively used for CABG.

[Percutaneous transluminal angioplasty of a constricting coronary artery bypass graft: a case report].

A case with percutaneous transluminal coronary angioplasty (PTCA) for the stenosis of saphenous vein bypass graft was reported. A 68-year-old woman developed repeated effort angina two months after emergency triple CABG. Coronary angiographic study revealed 90% stenotic lesion in a sequential vein graft which was located between proximal and distal OM. PTCA was successful to dilate the stenotic lesion from 90% to 25% narrowing. She has been free from angina after the CABG and PTCA.

[A case of discrete type of subpulmonary stenosis].

We reported a 8-year-old girl having discrete type of subpulmonary stenosis. This patient was associated with atrial septal defect (ASD), valvular pulmonary stenosis, and persistent left superior vena cava (PLSVC). The incidence of this type of subpulmonary stenosis is less frequent than that of subaortic lesion. ASD was closed by the autologous pericardium and a transannular patch was used for enlargement of the right ventricular outflow tract followed by commissurotomy of the pulmonary valve and resection of subpulmonary discrete lesion. She was uneventful and postoperative pulsed doppler echocardiogram showed good results.

[Coronary artery bypass grafting in a patient with Kawasaki disease].

A 3-year-girl admitted because of angina at rest. She had been diagnosed as Kawasaki disease at the age of 3 months. At that time, a coronary aneurysm was detected by echocardiogram and aspirin had started to administer. At the age of 4 months, a cardiac arrest occurred after severe heart attack because of inferior myocardial infarction. At the age of 2 years and 6 months, she started to complain of a chest pain even at rest. Coronary angiography was performed, and it showed total occlusion of RCA and LAD. However, LAD was vaguely filled by collateral flow from diagonal branch, and 201Tl scintigraphy showed myocardial viability of anteroseptal area. At operation, the size of ITA was 1.2 mm in diameter. Coronary artery bypass grafting to LAD by ITA was performed. Three weeks postoperatively, graft patency was confirmed by coronary angiography. The girl discharged with good ability of exercise. The ITA seemed to be the first choice of conduit for CABG even in a small child, and to be useful for progressive surgical treatment of Kawasaki disease.

Aortic dissections complicating open cardiac surgery: report of three cases.

Between June 1991 and February 1999, three patients suffered ascending aortic dissection as a complication of cardiopulmonary bypass operations with aortic cannulation at our hospital. The dissection occurred during the operation in two of the three patients and several months after the operation in one. Among a total of 2207 cardiac operations performed during this period, the incidence of perioperative ascending aortic dissection was 0.14%. In addition to visual inspection and palpation, either epicardial or transesophageal echocardiography proved extremely useful for establishing an intraoperative diagnosis of ascending aortic dissection as a complication of open cardiac operation. One of the three patients underwent closed plication but subsequently died of vital organ ischemia. In this case, failure of reapproximation of the injured intima by closed plication might have led to extension of the dissection. Despite prolonged cardiopulmonary bypass and myocardial ischemic time, graft replacement of the ascending aorta was successfully carried out in the other two patients. Thus, we believe that graft replacement of the ascending aorta should be performed for patients with extensive aortic dissection complicating an open cardiac operation.

[The second coronary reoperation via the left thoracotomy without cardiopulmonary bypass].

A 75-year-old female who had underwent coronary artery bypass grafting (CABG) reoperation 2 years before was readmitted because of unstable angina. Two arterial grafts and one saphenous vein graft (SVG) were all occluded one and half year after the primary operation. The second operation was approached via the repeated sternotomy. LAD and RCA were revascularized with a Y-shaped SVG which had only one inflow. Coronary angiogram revealed stenosis of LMT and RCA and occlusion of the inflow of the Y-shaped SVG. We performed the 3rd CABG via the left thoracotomy without cardiopulmonary bypass for revascularization of the LAD area. A new SVG was anastomosed from the descending aorta to the old SVG just proximal to the anastomotic site with LAD. Local coronary occlusion time was 7 min without any hemodynamic or electrocardiographic deteriorations. The operation was successfully performed in 3 hr 55 min. The patient recovered well uneventfully. Postoperative angiogram showed that the new SVG was adequately patent and she was discharged without angina. We conclude that CABG without cardiopulmonary bypass via the left thoracotomy is an useful alternative to decrease mortality and morbidity for reoperative myocardial reveascularization.

Morphological and functional study of free arterial grafts.

Morphological and functional changes of free arterial grafts in dogs were studied for 3 weeks after implantation and the changes were compared to those in implanted free vein grafts. In the arterial grafts, endothelial cells with abundant pinocytotic vesicles and some cytoplasmic folds were observed by transmission and scanning electron microscope and cell detachment was seen only at the site of anastomosis, while most cells were detached in the vein grafts. The site of mechanical damage in the arterial grafts was covered by regenerated endothelial cells which showed similar morphological findings to the normal arterial endothelial cells. In contrast, regenerated cells in the vein grafts started to cover the denuded area 7 days after the implantation and had completely covered it by 3 weeks. Prostacyclin was produced more abundantly in arterial grafts than in vein grafts at any phase after implantation. The level of prostacyclin production was between 30 and 40 pg/mg in any phase after implantation of free arterial grafts, while in vein grafts the level was 2.5 pg/mg at the day of implantation and increased to 13.6 pg/mg at 21 days. This study showed that the endothelial cells were well preserved and the level of prostacyclin production was high in the arterial grafts, and thus the grafts seemed to show potent anti-thrombogenicity after implantation. Although late changes in arterial and vein grafts were not investigated in this experimental protocol, these results may suggest that the arterial graft is superior to the vein graft even in the early period after its implantation as a free graft.