Yasuhiko Wanibuchi

Comparison of durability of bioprostheses in tricuspid and mitral positions.

BACKGROUND Few reports have assessed differences in the durability of mitral and tricuspid bioprostheses after simultaneous implantation of the same bioprosthesis in both positions. We investigated the long-term outcome after simultaneous mitral valve replacement (MVR) and tricuspid valve supraannular implantation (TVSI) with the Carpentier-Edwards bioprostheses in patients with severe tricuspid regurgitation and advanced mitral valve disease. METHODS Between 1982 and 1998, 37 patients in our hospital underwent MVR and TVSI with Carpentier-Edwards bioprostheses. The mean age of the patients was 55+/-11 years. The average postoperative follow-up was 7.9+/-4.5 years after surgery (range 0 to 14.6 years, 315.1 patient-years). The follow-up rate was 100%. We evaluated the actuarial survival rate, the actuarial freedom from structural valve deterioration (SVD) and reoperation, and postoperative complications. RESULTS The overall actuarial survival rate at 13 years after the operation was 69%+/-31%. The actuarial freedom from SVD and reoperation in the mitral and tricuspid positions were 78+/-22 and 100% and 70+/-30 and 90%+/-10% (p = 0.03), respectively. No patient had systemic or pulmonary thromboembolism, or complications associated with fatal arrhythmia. CONCLUSIONS These results suggest that the bioprostheses in the tricuspid position yield significantly better long-term results than those in the mitral position after simultaneous MVR and TVSI.

Coronary artery reoperation through the left thoracotomy with hypothermic circulatory arrest

BACKGROUND The left thoracotomy approach to avoid injury of the patent old graft and the myocardium with mid sternal reentry at coronary artery reoperation. METHODS The left thoracotomy approach was used in 13 patients. There were 11 men and 2 women with a mean age of 63 years, ranging from 39 to 75 years. Three patients were having their third coronary bypass operation. In 11 patients, distal anastomoses were performed under circulatory arrest with moderate hypothermia. In the other 2 patients, distal anastomoses were performed on a beating heart. No aortic cross-clamp was applied in all patients. The mean number of distal anastomoses was 1.8; the grafted vessels were 11 anterior descending, 3 diagonal, 8 circumflex, and 1 posterolateral coronary arteries. Used grafts were 17 saphenous veins, 4 left internal thoracic arteries, and 2 gastroepiploic arteries. Inflow sites of the free graft were descending aorta in 10 patients and left subclavian artery in 3 patients. RESULTS All patients were alive and well at the mean follow-up of 16 months, and all grafts were patent. CONCLUSIONS The left thoracotomy approach is safe and effective for reoperation on the left coronary artery system, and circulatory arrest is convenient and safe for performing distal anastomosis.

Availability of the in situ right gastroepiploic artery for coronary artery bypass

The right gastroepiploic artery (GEA) has been successfully used as a coronary bypass graft recently. We examined the in situ GEA graft length required from the pyloric portion to the site of coronary anastomosis at the time of operation. Measured GEA length was 17.0 +/- 1.7 cm for the posterior descending artery anastomosis in 17 patients, 17.8 +/- 1.7 cm for the main right coronary artery anastomosis in 13 patients, 22.0 +/- 2.3 cm for the posterolateral branch anastomosis in 7 patients, and 21.0 cm for the left anterior descending artery anastomosis in 1 patient. We examined 228 randomly selected abdominal angiograms and measured the internal diameter of the right GEA at every 2-cm interval from its origin. Probability of availability of the in situ GEA graft for each site of anastomosis was 97% to the right coronary artery and 88% to the anterior descending or the circumflex artery when the internal diameter of GEA was 1.5 mm or greater. From an anatomical standpoint, we concluded that the GEA can be assumed available without preoperative angiography.

Bovine internal thoracic artery graft for myocardial revascularization : late results

From May 1988 to March 1990, the bovine internal thoracic artery (ITA) graft, 3 mm in diameter, was used for coronary artery bypass grafting in 29 patients with the approval of the Japanese Ministry of Health. Excluding three postoperative deaths and 6 patients who rejected postoperative angiography, 20 patients (13 men and 7 women; mean age, 62 years; range, 37 to 80 years) were followed up angiographically for up to 4 years. Sites of bovine ITA anastomosis were as follows: anterior descending, 4; circumflex, 5; and right coronary artery, 11. The mean bovine ITA graft blood flow measured by electromagnetic flowmeter was 75.2 mL/min (range, 40 to 150 mL/min). During the mean follow-up of 45 months (range, 30 to 52 months), 12 patients underwent postoperative angiography once, 6 patients twice, and 2 patients three times. It revealed 14 of 16 (88%) bovine ITA grafts were patent within 2 postoperative months. Three of 6 (50%) were patent at 3 to 12 months, of which 2 patent grafts required balloon angioplasty for distal anastomotic stenosis. In 7 patients restudied later than 1 year (20, 24, 25, 44, 48, 50, and 52 months), one of seven grafts (14%) was patent. There was stenosis (> or = 50%) at four distal and one proximal bovine ITA anastomotic sites, but no focal stenosis was found in the trunk at any period. There was one late death due to renal failure, one myocardial infarction, and one mild angina due to bovine ITA graft failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler miniprobe to measure arterial graft flow in coronary artery bypass grafting

Using a 5 X 5-mm ultrasonographic Doppler miniprobe, the flow volume of arterial grafts (internal thoracic artery and gastroepiploic artery) was measured four times during the course of coronary artery bypass grafting. Graft flow just before sternal closure was almost equivalent to that in the preoperative phase when the anastomosis was optimal. Use of the Doppler miniprobe facilitated evaluation of the arterial graft flow pattern easily and quickly. We conclude that the Doppler miniprobe can provide helpful information for the evaluation of results of coronary artery bypass grafting in real time without necessitating any additional procedures.

The role of medical treatment of distal type aortic dissection

We analyzed the short-term and long-term outcome of 42 patients with distal type aortic dissection. Twenty-eight patients underwent intensive medical therapy within two weeks after the onset of pain (acute dissection). The remaining 14 patients had chronic dissection. The goals of medical treatment were to control blood pressure and to attain a negative C-reactive protein test result. Hospital survival rate in the patients with acute dissection was 96% (27/28). In-hospital complications included changes in mental status, renal dysfunction, bradycardia, orthostatic hypotension, and liver dysfunction, all of which were managed medically. Three of these patients underwent surgical therapy in the chronic phase and were discharged uneventfully. Fifteen (62.5%) of the 24 medically treated patients were discharged with negative C-reactive protein tests. Spontaneous resolution of a dissection was demonstrated by radiological examinations in 8 cases. Five-year survival rates in 24 medically treated patients was 93%. Hospital survival rate in the patients with chronic dissection was 100% (14/14). The rigorous control of blood pressure in the acute phase, and subsequent meticulous evaluation of the dissection by radiological tests and C-reactive protein test provides acceptable short-term and long-term outcomes of patients with acute distal dissection without the need for emergency surgical intervention.

Tricuspid valve supra-annular implantation in adult patients with Ebstein's anomaly

BACKGROUND Tricuspid valve supra-annular implantation (TVSI) has been performed for adult patients with Ebsteins anomaly at our hospital for several decades. TVSI is characterized by reliable reduction of tricuspid annulus size without affecting the conduction system; by prevention of residual tricuspid regurgitation (RTR) through preservation of the native tricuspid valve; and by implantation of the bioprosthesis at a supra-annular site. METHODS Ten adult patients with Ebsteins anomaly underwent TVSI. The right ventricular diameter and residual tricuspid regurgitation were evaluated by echocardiography preoperatively, at discharge, 1 year after the operation, and over the long term (12.4 +/- 5.5 years). Actuarial survival rate, actuarial freedom from structural valve deterioration rate, and postoperative occurrence of arrhythmia were also evaluated. RESULTS The actuarial survival rate at 19 years was 76 +/- 15%. Tricuspid regurgitation disappeared in 8 patients just after operation. Right ventricular diameter was significantly smaller at discharge than preoperatively (63 +/- 11 vs 37 +/- 9, p < 0.01), and there were no significant differences between values at discharge and at follow-up. The actuarial freedom from structural valve deterioration rate and the reoperation rate were both 100%. There were no fatal complications related to arrhythmia or thromboembolism. CONCLUSIONS TVSI is useful for adult patients with Ebsteins anomaly. The absence of complications related to fatal arrhythmia and thromboembolism, good durability of the bioprosthesis, and a simple operative procedure are merits of this therapy.

Metastatic atrial myxoma to the skin at 15 years after surgical resection

Metastasis from atrial myxoma is uncommon. We report on a patient who developed metastasis of the left atrial myxoma to the skin at 15 years after surgical resection. The primary lesion had not recurred. The myxoma has the potential for metastatic growth.

Gastroepiploic artery graft for anterior descending coronary artery bypass

In 308 right gastroepiploic artery (GEA) grafting procedures performed for myocardial revascularization, 38 GEA, 34 in situ, and four free grafts were used to bypass the left anterior descending coronary artery (LAD). Indications for using the GEA for the purpose of LAD bypass were: unavailability of the internal thoracic artery (ITA) at reoperation, surgical damage to the ITA at the time of the operation, or an apparently better free flow versus that in the left ITA, particularly in patients with diabetes mellitus in whom it was considered inadvisable to use bilateral ITAs. There were 21 male and 17 female patients with a mean age of 62 years (range, 31 to 77 years). Ten patients had undergone a previous myocardial revascularization. The mean number of distal anastomoses was 2.8 (range, 1 to 5). Concomitantly used conduits were the ITA in 27 patients, saphenous veins in 21 patients, the inferior epigastric artery in 4 patients, and the bovine internal thoracic artery in 1 patient. All but 1 patient survived. Follow-up ranged from 3 to 84 months (mean, 27 months). Postoperative angiography was performed in 33 patients. At the short-term evaluation (mean, 1 month), 32 of 33 (97%) GEA grafts were found to be patent; all 4 GEA grafts studied at the long-term evaluation (mean, 25 months) were also found to be patent. In no patients did angina recur postoperatively. In 25 patients who underwent an exercise study postoperatively, the stress test results were negative in 23.(ABSTRACT TRUNCATED AT 250 WORDS)

Central nervous system damage following surgery using cardiopulmonary bypass--a retrospective analysis of 1386 cases.

In order to determine the incidence and risk of central nervous system damage (CNSD) which accompanies cardiovascular surgery, a retrospective analysis was carried out on 1386 patients who received surgery utilizing cardiopulmonary bypass. CNSD occurred in 32 of the 1386 patients, the total incidence being 2.3 per cent. The major risk factors which led to a high incidence of CNSD were found to be reoperation, thrombus in the left atrium (TLA) and calcification of the ascending aorta (Cal aAo). In the primary surgical series, CNSD was found in only 29 of 1350 patients (2.2 per cent), however, of a total 36 patients who underwent reoperation, 3 (8.3 per cent) patients developed CNSD (p<0.05). In a surgical series done on 562 patients with mitral valve disease, the prevalence of CNSD was much higher in patients who suffered TLA than in those who did not, being 4/85 cases (4.7 per cent)vs 11/477 cases (2.3 per cent), respectively. Moreover, a significantly higher incidence of CNSD was noted in patients with Cal aAo, occurring in 6/10 cases (60 per cent) with Cal aAovs 4/333 cases (1.2 per cent) without Cal aAo (p<0.001). The results of this study showed that patients with CNSD, who had received coronary artery bypass surgery and aortic arch replacement tended to follow a poor clinical course, suggesting that atheromatous plaque embolization may be the leading cause of the poor prognosis following CNSD in patients having undergone cardiopulmonary bypass.