[Giant Right Coronary Artery Aneurysm Complicated by Acute Myocardial Infarction:Report of a Case]

The patient was a 45-year-old man who was transported by ambulance to a nearby clinic owing to sudden chest pain. He was diagnosed with myocardial infarction and giant coronary artery aneurysm by coronary arteriogram and underwent an emergency intervention for the myocardial infarction. The patient was referred to our hospital. Intraoperative findings showed the mass-like right coronary artery aneurysm at the anterior to the right atrium. The origin of the right coronary artery was ligated in addition to the fenestration and the proximal and distal regions of the coronary artery aneurysm. It has been reported that coronary artery aneurysms are usually asymptomatic and are often discovered by chance during screenings, such as echocardiography, computed tomography, and coronary arteriogram. Here, we report a surgical case of giant right coronary artery aneurysm complicated by acute myocardial infarction.

Detachment of a prosthetic valve due to infective endocarditis caused by Streptococcus pneumoniae

The incidence of infective endocarditis (IE) due to S pneumoniae has decreased, thanks to antibiotics. However, when it does occur, it can be lethal. The present case provides a reminder of the potential lethality of this postoperative infection.

[Perioperative Multiple Pulmonary Embolism in a Patient with Giant Right Atrial Myxoma: Report of a Case]

It is reported that 20% of cardiac myxomas are located in the right atrium. An 81-year-old man presented with dyspnea, general fatigue and leg edema lasting for a year. Echocardiography revealed an 80 mm tumor occupying the right atrium and the right ventricle. At surgery, the tumor attached to the atrial septum was removed with the surrounding septal wall. As the tricuspid annulus was dilated, tricuspid annuloplasty with an artificial ring was also carried out. After coming off cardiopulmonary bypass, the patient developed pulmonary hypertension with the pulmonary arterial pressure being 80% of the systemic pressure, which subsided gradually day by day. Histopathological diagnosis was cardiac myxoma. Postoperative lung perfusion scintigraphy revealed postoperative multiple defects. It was considered that multiple tumor embolisms in the distal pulmonary artery caused postoperative pulmonary hypertension. Careful follow-up for remote recurrence would be essential.

Aortic regurgitation due to fibrous strand rupture in the fenestrated left coronary cusp of the tricuspid aortic valve

Fenestration-related massive aortic regurgitation is rare. The underlying mechanism is reported to be rupture of the fenestrated fibrous strand, and most ruptured cords have been reported in the bicuspid valve or in the right coronary cusp of the tricuspid aortic valve. We encountered a rare case of acute aortic regurgitation due to fibrous strand rupture in the fenestrated left coronary cusp. Preoperative echocardiography detected left coronary cusp prolapse, and operative findings revealed rupture of a fibrous strand in the left coronary cusp. For cases such as this, preoperative echocardiography would be useful for appropriate diagnosis.

Aortic arch rerouting and OPCAB in a patient with situs inversus totalis

Endovascular therapy approaches for aortic aneurysm have lowered the mortality and morbidity rates even in high-risk patients; moreover, these approaches are applied in the management of aortic arch pathologies by transposition of the supra-aortic branches. We present the case of a 75-year-old female patient with situs inversus totalis on hemodialysis. The patient underwent off-pump aortic arch rerouting and thoracic endovascular aortic repair concomitant with coronary artery bypass grafting for distal aortic arch aneurysm and ischemic heart disease.

[Outcomes of the surgical treatment of infectious endocarditis in a single institute for 13-years]

Recently, due to the progress in patient managements with antibiotics, the prognosis of the active phase infectious endocarditis (IE) has improved, but in some cases, urgent or emergent surgical treatment is inevitable because of the uncontrollable acute heart failure due to valve regurgitation, uncontrollable infection with circulatory collapse, or high embolization risk. We reviewed the outcomes of the 57 IE patients who underwent surgical treatment in our hospital from January, 2000 to April, 2012. Preoperative state including inflammatory responses, bacterial blood culture, antibiotic administration, and surgical procedures were examined. No statistical significances were detected in the mortalities between elective cases (n=43)and urgent or emergent cases (n=14). Totally, mortality was 5.3% including one case in prosthetic valve endocarditis, and was satisfactory.

[Successful treatment of a case of chylothorax, manifesting as a complication following surgical treatment of coarctation of the aorta, by using octreotide acetate; report of a case]

Chylothorax - a serious postoperative complication of thoracic surgery - is associated with high morbidity and mortality, and re-exploration is required in many such cases. A 33-year-old male patient had undergone an extra-anatomic bypass for the treatment of coarctation of the aorta. Persistent chylothorax developed as a complication postoperatively. Octreotide acetate was administered 11 days postoperatively, which resolved the chylothorax without the need for surgical intervention. The patient was discharged from our hospital without any complications at 40 days postoperatively. In the present report, we describe this case and a provide a review of the literature.

Effect of the neutrophil elastase inhibitor sivelestat on perioperative inflammatory response after pediatric heart surgery with cardiopulmonary bypass: a prospective randomized study

Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response. The neutrophil elastase inhibitor sivelestat is known to suppress this systemic inflammatory response, which can eventually result in acute organ failure. The prophylactic effect of sivelestat on acute lung injury, especially in pediatric cardiac surgery, remains unclear. This prospective double-blind, randomized study evaluated the perioperative prophylactic effect of sivelestat in patients undergoing elective pediatric open heart surgery with CPB. Thirty consecutive patients, weighing 5-10 kg and undergoing open heart surgery with CPB, were assigned to sivelestat (n = 15) or control (n = 15) groups. From CPB initiation to 24 h after surgery, patients in the sivelestat group received a continuous intravenous infusion of 0.2 mg/kg/h sivelestat, whereas patients in the control group received the same volume of 0.9% saline. Blood samples were collected, and levels of interleukin (IL)-6, IL-8, tumor necrosis factor alpha, polymorphonuclear elastase (PMN-E), C-reactive protein (CRP), as well as the white blood cell (WBC) count, platelet count, and neutrophil count (NC) were measured. PMN-E levels, IL-8 levels, WBC count, NC, and CRP levels were significantly lower, and platelet count was significantly higher in the sivelestat group, according to repeated two-way analysis of variance. The activated coagulation time was significantly shorter in the sivelestat group, similarly, blood loss was significantly less in the sivelestat group. In conclusion, Sivelestat attenuates perioperative inflammatory response and clinical outcomes in patients undergoing pediatric heart surgery with CPB.

[Hybrid procedure for combined descending thoracic and abdominal aortic aneurysms]

In patients with previous infrarenal abdominal aortic aneurysm (AAA) repair, the risk of spinal cord ischemia increases after thoracic endovascular aortic repair (TEVAR) for a descending thoracic aortic aneurysm (DTAA). The case is a 67-year-old man with a 60 mm infrarenal AAA and a 73 mm DTAA. We performed the staged hybrid procedure for these aortic aneurysms. First of all we underwent a conventional AAA repair. The bilateral internal iliac arteries and a inferior mesenteric artery were preserved. In addition, the right leg of the tube graft was anastomosed to the right superficial femoral artery to facilitate access of TEVAR. Two months later we performed TEVAR for the DTAA. DTAA extended from the level of the 7th thoracic vertebra to that of the 11th thoracic vertebra. Although there was a certain risk of paraplegia, no complications occurred. The hybrid procedure for combined DTAA and AAA may be a valuable option.

Successful repair for a giant coronary artery aneurysm with coronary arteriovenous fistula complicated by both right- and left-sided infective endocarditis

We report a rare case of a 65-year-old woman who underwent an emergent lifesaving heart operation for an undiagnosed right coronary artery aneurysm with a coronary arteriovenous fistula complicated by active infective endocarditis, which affected the aortic valve, mitral valve, and coronary sinus. We performed direct closure of the coronary arteriovenous fistula, ligation of the right coronary artery aneurysm, double coronary artery bypass grafting, and double valvular replacement. Five years after the operation, she had no sign of congestive heart failure or infection, and was not receiving antibiotics.

Adult patent ductus arteriosus: successful surgery with mitral valvuloplasty

The development of left ventricular dysfunction is a serious complication of longstanding patent ductus arteriosus. An 80-year-old woman who underwent patent ductus arteriosus ligation 13 years previously developed congestive heart failure and mitral regurgitation. She underwent surgical repair with transpulmonary ductus closure and mitral valve annuloplasty under cardiopulmonary bypass. She made a full recovery with improved left ventricular function.

Excision of a cardiac papillary fibroelastoma with the use of a fiberscope

Cardiac papillary fibroelastoma (CPF) is a histologically benign tumor that can cause a significant embolic event. CPF is usually located on the endocardium, and is found on valves in 90% of cases. We experienced an unusual case of CPF situated on a left ventricular anterolateral papillary muscle. An 84-year-old female who had developed cerebellum infarction five months previously underwent surgical resection of CPF. During surgical resection of the tumor, a fiberscope was useful for detecting the lesion, and allowed us to ensure complete resection with a good surgical view. Our experience encourages us to use the fiberscope when resecting other intracardiac masses, including thrombi.

High-output heart failure caused by arteriovenous fistula long after nephrectomy

A 70-year-old Japanese woman was admitted to our hospital because of anasarca. At 32 years of age, she had undergone nephrectomy for renal tuberculosis. A continuous abdominal bruit was heard. The chest X-ray showed cardiomegaly and dilatation of the pulmonary artery. Abdominal three-dimensional computed tomography scanning clearly revealed an arteriovenous fistula. Cardiac catheterization disclosed cardiac output of 9.2 l/min and a step-up of oxygen saturation at the renal vein level of the inferior vena cava. Surgical closure of the fistula promptly decreased her cardiac output and improved the heart failure. This is a rare case of an arteriovenous fistula developing long after nephrectomy and causing high-output heart failure.

Determinants of Incomplete Left Ventricular Mass Regression Following Aortic Valve Replacement for Aortic Stenosis

OBJECTIVE

Incomplete regression of left ventricular hypertrophy (Abn-LVMI) following AVR for aortic stenosis (AS) may decrease long-term survival. In this prospective study, we identified the predictors of Abn-LVMI.

METHODS

Between 1990 and 2000, 529 patients undergoing AVR for AS had clinical and hemodynamic data collected prospectively. Preoperative and annual postoperative transthoracic echos were employed to assess left ventricular mass index (LVMI) and hemodynamics. Abn-LVMI was defined as the 75th percentile of the lowest postoperative LVMI (>128 mg/m2, n = 133). All other patients were included in the normal regression group (N-LVMI). Univariate and multivariable logistic regression analyses were used to determine the predictors of Abn-LVMI.

RESULTS

Preoperative hypertension, diabetes, coronary disease, valve size, mean postoperative gradients, effective orifice area, and patient-prosthesis mismatch (PPM, indexed EOA <0.60 cm2/m2) did not predict Abn-LVMI. By logistic regression the most important positive predictor of Abn-LVMI was the extent of preoperative LVMI, with an odds ratio of 37.5 (p < 0.0001). Survival (93.4 +/- 1.8% vs 94.8 +/- 2.3%, p = 0.90) and freedom from NYHA III-IV (75.0 +/- 3.7% vs 76.6 +/- 5.3%, p = 0.60) were similar for both groups at 7 years.

CONCLUSIONS

Measures of valve hemodynamics were not important predictors of incomplete regression of hypertrophy. The extent of preoperative hypertrophy was the most important predictor, suggesting that earlier surgical intervention may reduce the extent of hypertrophy postoperatively. Furthermore, the significance of LV hypertrophy to long-term survival must be reassessed, in the absence of scientific evidence.

Contemporary Trends in Aortic Valve Surgery:. A Single Centre 10-Year Clinical Experience*

The purpose of this study is to present a comprehensive profile of the trends in aortic valve replacement at a single institution over the past decade. Prospectively collected data concerning 873 patients undergoing aortic valve replacement (AVR), with and without coronary artery bypass grafting (CABG), were analysed. The patients were divided into three time periods: period I, (1990 to 1993); period II, (1994 to 1996); and period III, (1997 to 2000). Actuarial survival of AVR patients with and without CABG at 7 years was 82.9 +/- 2.4% and 79.1 +/- 3.3% (p = 0.17), respectively. Actuarial survival at 7 years for stentless, mechanical, and stented valve patients were 89.5 +/- 2.7%, 85.5 +/- 2.8%, and 76.0 +/- 3.2%, respectively. There was a significant difference in survival between the stentless and stented valve groups (p = 0.014). Age (63.8 +/- 12.9 yrs, 66.2 +/- 11.0 yrs, 67.9 +/- 10.3 yrs; p = 0.01), the incidence of peripheral vascular disease (5.1%, 10.8%, 16.6%; p = 0.001), and the extent of coronary artery disease necessitating CABG (34.0%, 38.8%, 41.0%; p = 0.05) have increased significantly in the later time period. However, operative mortality has remained constant (4.7%, 4.8%, 4.5%; p = 0.9). Moreover, perioperative complications have decreased significantly (27.4%, 18.0, 16.0%; p = 0.001). Multivariate analysis identified more recent time period as independent protective factor for early mortality and morbidity (period I, RR 1.00; period II, RR 0.47; period III, RR 0.40).

The short-term and long-term effects of warm or tepid cardioplegia

BACKGROUND

Clinical studies of myocardial protection rarely identify differences in hard clinical outcomes after surgery, either early or late, because most trials lack sufficient statistical power to deal with low-frequency events.

METHODS

Prospectively collected data concerning all isolated coronary bypass operations from November 1989 to February 2000 were analyzed to determine the effects of cold blood cardioplegia and warm or tepid blood cardioplegia on early and late outcomes after surgery. Warm blood cardioplegia was used in 4532 patients, whereas cold blood cardioplegia was used in 1532. The allocation of patients to receive warm blood cardioplegia and cold blood cardioplegia was random in 749 cases and according to surgeon preference in the remainder. Most patients in the cold blood cardioplegia group had surgery earlier in the time course of the study, and most in the warm blood cardioplegia group underwent surgery later.

RESULTS

Perioperative death, myocardial infarction, and death or myocardial infarction were all more common in the cold blood cardioplegia group than in the warm blood cardioplegia group (death 2.5% vs 1.6%, P =.027, adjusted odds ratio 1.45, 95% confidence interval 0.95-2.22, P =.09; myocardial infarction 5.4% vs 2.4%, P <.0001, adjusted odds ratio 1.86, 95% confidence interval 1.36-2.53, P <.0001; death or myocardial infarction 7.3% vs. 3.8%, P <.0001, adjusted odds ratio 1.70, 95% confidence interval 1.30-2.21, P <.0001). Actuarial survival at 60 months was 91.1% +/- 1.4% in the warm blood cardioplegia group and 89.9% +/- 1.3% in the cold blood cardioplegia group (P =.09), whereas freedom from death or myocardial infarction was 84.7% +/- 1.8% and 83.2% +/- 1.6%, respectively (P =.16). In multivariate models, cold blood cardioplegia was associated with poorer survival (risk ratio 1.30, 95% confidence interval 0.96-1.75, P =.09) and freedom from any death or late myocardial infarction (risk ratio 1.93, 95% confidence interval 1.56-2.39, P =.0001).

CONCLUSIONS

In 6064 patients undergoing isolated coronary artery bypass grafting, warm or tepid blood cardioplegia may be associated with better early and late event-free survivals than is cold cardioplegia.

Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant

BACKGROUND

Although small valve size and patient-prosthesis mismatch are both considered to decrease long-term survival, little direct evidence exists to support this hypothesis.

METHODS

To assess the prevalence of patient-prosthesis mismatch and the influence of small valve size on survival, we prospectively studied 1,129 consecutive patients undergoing aortic valve replacement between 1990 and 2000. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography postoperatively (3 months to 10 years). Abnormal postoperative gradients were defined as those patients with mean or peak gradient above the 90th percentile (mean gradient > or = 21 or peak gradient > or = 38 mm Hg). Patient-prosthesis mismatch was defined as those patients with indexed effective orifice area below the 10th percentile (< 0.60 cm2/m2).

RESULTS

A multivariable analysis identified internal diameter of the implanted valve as the only independent predictor of abnormal gradients postoperatively. However, there was no significant difference in actuarial survival between normal and abnormal gradient groups (7 years: 91.2% +/- 1.5% versus 95.0% +/- 2.2%; p = 0.48). Freedom from New York Heart Association class III or IV (7 years: 74.5% +/- 3.1% versus 74.6% +/- 6.2%; p = 0.66) and left ventricular mass index were not different between normal and abnormal gradient groups. Patients with and without patient-prosthesis mismatch were similar with respect to postoperative left ventricular mass index, 7-year survival (95.1% +/- 1.3% versus 94.7% +/- 3.0%; p = 0.54), and 7-year freedom from New York Heart Association class III or IV (79.3% +/- 6.6% versus 74.5% +/- 2.5%; p = 0.40). In patients with patient-prosthesis mismatch and abnormal gradients, the majority had prosthesis dysfunction owing to degeneration.

CONCLUSIONS

Severe patient-prosthesis mismatch is rare after aortic valve replacement. Patient-prosthesis mismatch, abnormal gradient, and the size of valve implanted do not influence left ventricular mass index or intermediate-term survival.

Are stentless valves hemodynamically superior to stented valves? A prospective randomized trial

BACKGROUND

Although stentless aortic bioprostheses are believed to offer improved outcomes, hemodynamic benefits remain unsubstantiated.

METHODS

Fifty-three patients were randomized to receive the stented C-E pericardial valve (CE) and 46 patients the Toronto Stentless Porcine valve (SPV). Annuli were sized for the optimal insertion of both valve types, such that surgeons were required to commit to specific valve sizes before randomization. Echocardiographic measurements and functional status (Duke Activity Status Index) were assessed at 3 and 12 months postoperatively.

RESULTS

Although cardiopulmonary bypass times (CE: 118.6+/-36.3 minutes; SPV: 148.5+/-30.9 minutes; p = 0.0001) and aortic cross-clamp times (CE: 95.4+/-28.6 minutes; SPV: 123.6+/-24.1 minutes; p = 0.0001) were significantly prolonged in the SPV group, perioperative morbidity and mortality was similar between groups. Neither valve offered a superior internal diameter for any given annular diameter (mean decrease in left ventricular outflow tract diameter after valvular implantation: SPV: 3.4+/-1.11 mm versus CE: 3.7+/-1.33 mm; p = 0.25). Although labeled mean valve size was significantly larger in the SPV group, the actual mean valve size based on internal valvular diameter was no different between groups (CE: 21.9+/-2.0 mm; SPV: 22.3+/-2.0 mm; p = 0.286). Although effective orifice areas increased, and mean and peak transvalvular gradients decreased in both groups over time, no differences were demonstrated between groups at 12 months. Similarly, although significant regression of left ventricular mass was accomplished in both groups over time, no differences were demonstrated between groups. Finally, Duke Activity Status Index scores of functional status improved in both groups over time; however, no differences were noted between groups at 12 months postoperatively.

CONCLUSIONS

Although offering excellent outcomes, stentless valves did not demonstrate superior hemodynamic indices in comparison to stented valves up to 12 months after implantation.

Initial experience with off-pump coronary artery bypass grafting

Off-pump coronary artery bypass grafting (OPCAB) is clearly preferable for patients with extracardiac complications. The aim of this study was to evaluate the initial outcome of OPCAB, and its validity for patients with extracardiac complications. One hundred and fifty-seven consecutive coronary artery bypass graft (CABG) patients were divided into two groups: 30 OPCAB patients and 127 on-pump CABG patients. The early outcomes of the two groups were compared. Preoperatively, OPCAB patients had more extracardiac risk factors than on-pump CABG patients. There were no differences in age or cardiac function between the groups, but the off-pump group had a higher incidence of previous surgery, cerebrovascular disease, and renal failure. There were no differences in graft patency, stroke, or mortality between the two groups, even though the OPCAB patients had more risk factors than the on-pump patients. Our initial experience with OPCAB showed that it is acceptable for high-risk patients in view of the serious nature of their extracardiac condition.

Staged coronary artery bypass grafting after percutaneous angioplasty for intracranial vascular stenosis

OBJECTIVE

Cerebrovascular disease is commonly associated with coronary artery disease and is a major risk factor for cardiac surgery. Concomitant coronary artery bypass grafting and carotid endarterectomy may reduce the risk of stroke; however, this staged operation is effective only for extracranial lesions. The strategy for on-pump coronary artery bypass grafting for patients with intracranial vascular stenosis is still controversial.

METHODS

The subjects were 157 consecutive candidates for coronary artery bypass grafting who underwent computed tomography and digital subtraction cerebral angiography preoperatively to check for cerebrovascular disease. Additional single-photon emission computed tomography was performed to evaluate cerebral ischemia, according to the neurologist's request. Patients with diffuse intracranial vascular stenosis impossible to treat with percutaneous transluminal angioplasty underwent off-pump coronary artery bypass grafting. Patients with a circumflex coronary artery lesion first underwent percutaneous transluminal angioplasty for cerebral vascular stenosis followed by secondary on-pump coronary artery bypass grafting.

RESULTS

Three patients were selected for staged operations. Percutaneous transluminal angioplasty was performed for 4 intracranial stenotic lesions. All lesions were dilated successfully, and no complications developed during or after the procedure. All patients tolerated staged coronary artery bypass grafting and were extubated within 1 day without any mental disturbance. No further neurologic complication occurred, and computed tomography performed postoperatively revealed no significant changes.

CONCLUSION

Staged on-pump coronary bypass after percutaneous transluminal angioplasty for cerebrovascular disease may reduce the risk of stroke during cardiopulmonary bypass, and it is useful especially in patients with intracranial cerebrovascular disease.

Mid-term follow up results of Japanese heart transplant patients operated in UCLA Medical Center

Japanese candidates have been accepted for heart transplantation by the UCLA Medical Center in the US since 1993 due to the lack of donors available from brain-dead patients.

OBJECTIVES AND METHODS

We monitored to patients who underwent such heart transplantation and have been seen at the out-patient clinic at Tokyo Women's Medical University following transplantation. Pre-operative diagnosis was dilated cardiomyopathy in all patients. One patient underwent Novacor implantation as a bridge to heart transplant. All patients underwent cardiac echocardiography and cardiac catheterization including intraluminal echography.

RESULTS

All patients survived with an actuarial survival curve of 100% at 1 year, 100% at 3 years and 87% at 5 years in 4.15 years of average follow-up. Two patients died due to liver dysfunction and cerebral emboli. The postoperative functional status of patients was New York Heart Association classification I in 8 (100%). Immunosuppressive therapies included triple drug therapy using either cyclosporin or tacrolimus. The incidence of acute rejection (/pt) exceeding grade 3 was 4% within three months, 3.5% in 3-6 months, and no significant rejection episode more than 6 months after transplantation. Posttransplantation coronary artery disease was seen in 2 patients, but no progression was seen after diltiazem therapy.

CONCLUSION

Our postoperative follow-up after cardiac transplantation appears to be satisfactory.

[Management of patient with acute myocardial infarction due to left main trunk obstruction]

Between April 1995 and March 1998, we experienced 13 cases of Acute Myocardial Infarction due to Left Main Trunk Obstruction (LMT-AMI). Two cases died before emergent intervention. Eight cases underwent emergent intervention (Plain Old Balloon Angioplasty (POBA) in five cases, Stenting in 3 cases); 2 cases died of acute occlusion of POBA site, 1 case survived by only POBA, and the other 5 cases underwent following Coronary Artery Bypass Grafting (CABG). 3 cases underwent only CABG with stable hemodynamics condition by Intraaortic balloon pumping (IABP) support. In a result, seven of eight CABG cases survived. Emergent stenting made the hemodynamics before CABG stable, and six-month's follow up angiogram showed occluded bypass grafts and patent stented sites in two of three cases. The combination therapy of emergent stenting and CABG will have to be evaluated in future.

[Reoperative off-pump subclavian-coronary artery bypass grafting in an elderly patient with left internal thoracic artery stenosis]

A 80-year-old Japanese female was diagnosed to have angina pectoris and admitted to our hospital. She had been operated on with mitral valve replacement and coronary artery bypass grafting to right and circumflex coronary artery 4 years before. The coronary angiogram showed significant stenosis with severe calcification in the left anterior descending coronary artery, and it was unsuitable for catheter intervention. The patient also had stenotic left internal thoracic artery and multiple cerebral infarction, but successful off-pump subclavian-coronary artery bypass grafting using saphenous vein graft through small thoracotomy was performed without new neurological deficit. This procedure is useful for patients with left internal thoracic artery unsuitable for MIDCABG, due to quality, size, or injury during preparation.

Should the aortic valve homograft be recryopreserved?

BACKGROUND

The number of homograft donors is limited and the once-thawed homograft may be unsuitable for the recipient and obliged to be wasted. The purpose of this study was to investigate the possibility of recryopreserving and using the once-thawed homograft for another patient.

METHODS

Canine aortic valve leaflets were frozen to -80 degrees C by a programmed freezer, stored in liquid nitrogen, and thawed after 1 week. A subgroup of leaflets was left at 4 degrees C for 15 minutes, re-cryopreserved, and thawed after 1 week. Pathologic and flow cytometric evaluations were performed.

RESULTS

After thawing, by pathology, alignment of the fibers was acceptably maintained but the membrane and cytoplasm of the fibroblast were damaged. These findings were not significantly aggravated even after rethawing. By flow cytometry, fibroblast viability was 90.7%+/-1.7% immediately after thawing, 87.6%+/-1.0% after thawing for 15 minutes at 4 degrees C, 63.7%+/-2.7% during refreezing at 0 degrees C, and 39.4%+/-4.3% after rethawing.

CONCLUSIONS

From the standpoint of fibroblast viability, it is not possible to recryopreserve the once-cryopreserved and thawed aortic valve homograft.

Clinical assessment of prolonged myocardial preservation for patients with a severely dilated heart

BACKGROUND

The purpose of this study was to compare the myocardial protective effect of histidine-tryptophan-potassium and glucose-insulin-potassium cardioplegic solutions in patients with a dilated heart (left ventricular diastolic diameter > 55 mm, left ventricular systolic diameter > 45 mm) associated with prolonged cross-clamp time (longer than 200 minutes).

METHODS

We selected 20 patients with dilated hearts due to severe aortic regurgitation. Glucose-insulin-potassium cardioplegia was used in 11 patients and histidine-tryptophan-potassium cardioplegia was used in 9 patients.

RESULTS

After operation, the cardiac index was significantly increased in the histidine-tryptophan-potassium group (p < 0.05). Postoperative percent fractional shortening was 13.4% +/- 3.1% in the glucose-insulin-potassium group and 23.6% +/- 2.6% in the histidine-tryptophan-potassium group (p < 0.05). Creatine kinase levels were significantly lower in the histidine-tryptophan-potassium group than that in the glucose-insulin-potassium group (p < 0.05). The incidence of ventricular arrhythmia (higher than Lown's grade 2) was lower in the histidine-tryptophan-potassium group.

CONCLUSIONS

These data support the superiority of the histidine-tryptophan-potassium method over the glucose-insulin-potassium method for protection of the dilated heart during prolonged ischemia in open heart operations.

Hypertrophic obstructive cardiomyopathy with abnormalities of the mitral valve complex

The mechanism of obstruction of the left ventricular outflow tract (LVOT) in hypertrophic obstructive cardiomyopathy (HOCM) is mainly due to dynamic systolic anterior motion (SAM) of the mitral valve. We report a case of HOCM with mitral regurgitation (MR) associated with complicated abnormalities of the mitral apparatus which contributed to a high pressure gradient through the LVOT. A small, 53-year-old woman was admitted for chest pain and palpitation. Examinations revealed asymmetric septal hypertrophy of the left ventricle, MR, SAM of the mitral valve and a high pressure gradient (108 mmHg) through the LVOT. Operative findings revealed an abnormally hypertrophied interventricular septum, an extensively thickened and enlarged anterior mitral leaflet (AML), malposition of the origin of the anterior papillary muscle arising closer to the aortic annulus than normal, and its direct insertion into the AML without any distinguishable chordae tendineae. The hypertrophied septum and the large and protruding AML appeared to obstruct the LVOT, resulting in a loss of subaortic clearance that was recovered after mitral valve replacement and myectomy. Pathology of the papillary muscle was characteristic of HOCM, showing disorganization and disarray of myocardial fibers, bizarre-shaped nuclei, and intercellular fibrosis, while those of the mitral leaflets negated both rheumatic changes and endocarditis.

[Reoperation for malfunction of Ionescu-Shiley bovine pericardial bioprosthetic valves in the mitral position--special consideration with emergency operation]

Sixty-eight patients have had mitral valve replacement with Ionescu-Shiley bovine pericardial bioprosthesis from 1981 to 1984. Thirty five patients were required reoperation due to primary tissue failure of the bioprosthesis, 10 (28.6%) were on emergency basis and 25 (71.4%) were on elective. Hospital deaths were two (20.0%) on emergency and four (16.0%) on elective. Clinical features of emergency cases were as follows: progressive congestive heart failure in eight, severe hemolysis with massive hemoglobinuria in eight and acute renal failure in four. Cusp tears were observed in all valves, 8.1 +/- 1.5 mm in emergency group and 4.2 +/- 3.6 mm in elective group. Neointimal ingrowth over Dacron cloth of the inner surface of the stent was absent in 29 valves (89.2%). Calcification was observed in seven valves, however these were not dominant causes of primary tissue failure. Clinical symptoms were correlated with structural deterioration of explanted valves. Structural deterioration of the bioprosthesis may occur suddenly and progressively. Our experience demonstrated that life-threatening prosthetic valve failure may occur with a relatively high incidence and that careful follow-up is needed for Ionescu-Shiley bovine pericardial bioprosthesis.

[A case report of a successful surgery for thoracoabdominal aortic aneurysm under partial cardiopulmonary bypass with selective perfusion of major abdominal branches]

A 69-year-old man showed gradually developing thoracoabdominal aortic aneurysm (TAAA) after coronary artery bypass grafting. The patient underwent graft replacement of TAAA uneventfully under partial cardiopulmonary bypass with selective perfusion of major abdominal branches. The major abdominal branches and two pairs of intercostal arteries were reconstructed. The patient showed no organ failure or spinal damage postoperatively. Partial cardiopulmonary bypass with selective perfusion of abdominal branches successfully protected both the visceral organs and the spinal cord from ischemia in a TAAA surgery.

[Sinus venosus atrial septal defect: report of two cases with successful repair by the Vargas' procedure]

Two cases of sinus venosus atrial septal defect with partial anomalous of right upper pulmonary venous drainage into superior vena cava treated by the Vargas' procedure were reported. These patients were 5 and 6 years old. Post operative courses were uneventful, and results of postoperative hemodynamic and clinical evaluation were encouraging. The Vargas' procedure is useful method for a reconstraction of the anomaly in childhood because of use of the autologus tissues. Though long-term fate of this procedure is still uncertain. Then, we consider that a long-term follow up is necessary.

[Report of a case with re-mitral valve replacement for Björk-Shiley Delrin disc valve prosthesis--disc wear of the Delrin disc 20 years after implantation]

We reported a patient in whom slight congestive heart failure gradually developed 20 years after mitral valve replacement with a Delrin disc Björk-Shiley valve prosthesis. Although no evident cause of prosthetic valve malfunction could be detected preoperatively, the mitral prosthesis was excised and replaced uneventfully with a 29 mm St. Jude Medical valve prosthesis. At gross inspection, marked wears of the Delrin disc surface and strut shaped indentations were present. These disc variance, occurred much earlier than initially predicted by Dr. Björk, allowed prosthetic valve malfunction. The patient with this specific model should be carefully followed-up, if necessary, performed reoperation.

Surgical treatment of ischaemic valve disease

Mitral valve regurgitation secondary to ischaemic heart disease carries a significant mortality even after open-heart surgery. In this study, 21 patients with mitral regurgitation associated with ischaemic heart disease were evaluated with respect to valvular pathology. Pathological examination of the mitral valve revealed chorda elongation or rupture in seven patients (group 1), papillary muscle dysfunction in 10 (group 2), and papillary muscle rupture in four (group 3). Significant preoperative characteristics in each group were subacute haemodynamic deterioration in group 1, chronic severe left ventricular failure in group 2, and a high incidence of acute renal failure associated with haemodynamic shock in group 3. Mitral valve plasty was performed in six patients and mitral valve replacement, using the St Jude Medical valve, in 15. Fourteen patients underwent mitral valve surgery combined with coronary artery bypass grafting. Mitral plasty was applied to the patients with low left ventricular function with mean(s.d.) fraction shortening of 19.2(6.2)% compared with 30.2(8.4)% in patients with mitral valve replacement. There were no operative deaths. Of four late deaths, two in group 1 resulted from infection and myocardial infarction, respectively and one in group 2 resulted from arrhythmia. One patient in group 3 died from renal failure. It is suggested that incorporation of these therapeutic concepts may lead to satisfactory results in the surgical treatment of ischaemic mitral regurgitation.

Combined aortic and mitral valve replacement in an adult with mucopolysaccharidosis (Maroteaux-Lamy syndrome)

A 41-year-old man with aortic stenosis, mitral stenosis, and tricuspid regurgitation due to Maroteaux-Lamy syndrome underwent aortic and mitral valve replacement with tricuspid annuloplasty. The annular diameter of the aortic and mitral valves was extremely small. The valve prostheses were 19 mm in diameter in the aortic position and 25 mm in the mitral position. Histologically, the valves showed thickening and hyalinization of the collagen fibers, and the presence of foamy cells that contained a large quantity of pure acid mucopolysaccharide. On an echocardiographic examination performed 2 years after the surgery, the peak systolic gradient of the trans-aortic valve was 18 mmHg at rest, and 26 mmHg during exercise. Careful observation of the residual pressure gradient will be needed. The patient's present New York Heart Association (NYHA) status is grade I and he has returned to work.

[Two cases of left atrial myxoma originating from mitral annulus]

We experienced two cases of left atrial myxoma originating from mitral annulus. Mitral valve replacement and mitral valvulo-annuloplasty were performed in each case, because of the presence of mitral leaflet defect due to removal of the myxoma. Two dimensional echocardiography was a useful method to confirm the location and decide the surgical approach.

[Repeat open heart surgery in a case associated with persistent left superior vena cava: a method of simple occlusion of L-SVC using an alternative extra-pericardial approach and retrograde cardioplegia]

Twelve years ago, we reported a method of extrapericardial approach to the L-SVC. Since then we have used this approach and performed simple occlusion of L-SVC during cardiopulmonary bypass without any cerebral complications. We have been expecting for a long time and have believed that this method will be very valuable especially in repeat open heart surgery. A case of 49-year-old man successfully underwent a redo operation for mitral and tricuspid valve replacement using extrapericardial occlusion of the L-SVC and retrograde cardioplegia. Although there was a pitfall for retrograde cardioplegia in the persistent L-SVC and a possibility of steal of cardioplegic fluid through a branch of the accessory hemiazygos vein during retrograde cardioplegia for a case with persistent L-SVC, sufficient cardiac protection was obtained in the case presented.

The role of leukocyte depletion in reducing injury to myocardium and lung during cardiopulmonary bypass

Activated leukocytes and oxygen free radicals have been implicated in the pathogenesis of heart and lung injury after reperfusion and during cardiopulmonary bypass. This study was designed to determine whether leukocyte depletion prevents injury to the heart and lung during cardiopulmonary bypass. Twenty-eight open heart surgeries were performed in this study. In Group F, leukocyte depletion was performed with an LG-6 arterial line filter after aortic declamp (n = 14). Leukocyte depletion was not performed during cardiopulmonary bypass in Group C (n = 14). Thereafter, cardiac and lung function were assessed in the 24 hr after reperfusion. The total catecholamine dose used for 24 hr after reperfusion (r) was 61.9 +/- 13.4 in Group C and 43.9 +/- 19.2 in Group F (p < 0.05). CK-MB at 3 and 6 hr after reperfusion was 65.9 +/- 13.5 and 64.8 +/- 15.8 in Group C and 45 +/- 11.8 and 38 +/- 10.8 in Group F, respectively (p < 0.05). The pulmonary index after reperfusion at 3 and 6 hr was 1.7 +/- 0.5 and 1.3 +/- 0.4 in Group C and 0.7 +/- 0.3 and 0.6 +/- 0.4 in Group F, respectively (p < 0.05). There was significantly better preserved lung function in Group F. In conclusion, leukocyte depletion was significantly effective in preserving heart and lung function during cardiopulmonary bypass.

[Early omental transposition for postoperative sterno-mediastinitis]

We report 3 successful cases of postoperative sterno-mediastinitis treated with single-stage procedure. 2 of them were infected with MRSA (Methicillin resistant staphylococcus aureus), and the other was with klebsiella pneumoniae. Neither open drainage nor irrigation were performed previously, but only administrations of sensitive antibiotics. Intensive debridement, irrigation and omental transposition were performed at one time, between 6 and 15 days from the diagnosis. It could achieve decrease of hospitalization. We recommend early single-stage procedure with omental transposition for postoperative sterno-mediastinitis before extension and aggravation of the infection.

[Preservation of fresh homograft using TC199 solution in rat]

The surgical replacement of human vessels using fresh allografts (homograft) has been reported as useful means. Nevertheless, little is known about preservation effect and immunological consequences using TC199 solution. In this study, defined inbred strains of rats were used. The aorta was extracted from Buffalo rats and preserved for 1, 2, and 3 weeks in TC199 solution at 4 degrees C. The preserved graft was then implanted into the Buffalo rats heterotopically, in the abdominal aorta, in the autotransplant group (AUTO) and into the Lewis rat in the allotransplant group (ALLO). The graft patency and histology including immunohistochemical stain (IgG, IgM, and C3 complement) were assessed at 2 weeks after transplantation. In AUTO, the patency was 100% with grafts 1 and 2 weeks' preservation, and 80% with 3 weeks' preservation. In the ALLO, patency was 100% with grafts with one week's preservation, 80% in those with 2 weeks' preservation and 0% those with in 3 weeks' preservation. Histology revealed that fibroblasts and endothelial cells were significantly deteriorated in 3 weeks' preservation in auto transplantation, however, they were well-maintained in 2 weeks' preservation. In the allo-transplantation group, histological deterioration began after 2 weeks preservation. Immunohistochemical staining showed significant deposits of IgG, IgM and C3 in ALLO. Significant infiltration of antibodies was seen in deteriorated tissue due to prolongation of the preservation periods. These results suggested that freshly preserved allograft was antigenic and 2 weeks preservation using TC199 solution was possible in the rat model.

Successful reconstruction of aorto-left atrial fistula following aortic valve replacement and root enlargement by the Manouguian procedure

Successful reconstruction of the aortic annulus for perivalvular leak following combined valve replacement was performed in two patients, 6 and 7 years postoperatively, using Manouguian's operation. A fistula was seen at the junction of the aortic annulus and the superior or inferior margin of the patch used for enlargement. This fistula was closed from both sides; from the left atrium with reinforced Teflon pledgets and from the aorta using a patch. Successful reconstruction of the aortic annulus was made, and no regurgitation was seen after the operation.

[Pre and postoperative management of a patient after cardiac transplantation performed in UCLA]

The patient with dilated cardiomyopathy (NYHA grade 4) underwent cardiac transplantation at University of California, Los Angeles. Postoperative management in our institute consisted 1) cardiac biopsy, 2) measurement of blood concentration of cyclosporin, 3) serum anti-CMV titer, 3) echo cardiography, 4) counts of lymphocyte subsets. Cardiac rejection (Ib) was observed 2 months after transplantation and steroid pulse therapy (methylprednisone 500 mg/day) was performed for 3 days. Blood concentration of cyclosporin was decreased with administration of probucol and increased with diltiazem. Presently, the patient is stable and back to normal work.