[Successful management of ruptured aortic arch aneurysm infected with methicillin-resistant Staphylococcus aureus]

A 64-year-old woman was admitted due to back pain and dyspnea. She was suffering from fever of unknown origin for a few weeks without aortic aneurysm by enhanced chest computed tomography (CT). Chest CT taken 1 month later revealed rupture of aortic arch aneurysm. Total arch replacement was performed with in situ grafting under selective cerebral perfusion combined with deep hypothermic circulatory arrest. Rifampicin (RFP) was sprinkled on the graft at operation and omentopexy was done 5 days after the 1st operation. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated on the culture of the aneurysmal wall, therefore, polymyxin B immobilized fiber with direct hemoperfusion (PMX-DHP) was also conducted with antibiotic therapy. Her clinical course after the 2nd operation was uneventful with no infective complication. We report a successful case of ruptured aneurysm of aortic arch infected with MRSA and review our strategy as one of feasible options without using homograft or preparative RFP-bonded vascular prosthesis.

[Atrial rupture due to blunt chest trauma]

Atrial rupture by blunt trauma is lethal and one of controversial problems for cardiovascular surgeons, because of complexed conditions due to multiple organ injuries. Some papers recommend strategy of early diagnosis and treatment at an acute phase for better clinical course, but high mortality rate has not been improved yet, especially that of left atrial rupture. Three patients were reffered to our hospital by blunt chest trauma, one of whom died due to hemorrhagic shock before receiving surgical or interventional treatment. The remaining 2 patients had surgical operations at an early phase and were discharged without severe complications. We review our strategy of atrial rupture of blunt chest trauma. At an acute phase, atrial rupture alone should be repaired urgently unless use of cardiopulmonary bypass is contraindicated by severe hemorrhage of the other organs.

MR angiographic evaluation of carotid and intracranial arteries in Japanese patients scheduled for coronary artery bypass grafting

BACKGROUND AND PURPOSE

Stroke is a serious complication of coronary artery bypass grafting (CABG). Preoperative evaluation of the cerebral arteries to identify patients at increased risk of stroke after CABG is important. In a prospective study, we evaluated cerebral artery occlusive lesions with MR angiography in Japanese patients scheduled to undergo CABG to determine the prevalence of occlusive diseases in the extracranial carotid and intracranial arteries in this population and to identify preoperative risk factors for these patients.

METHODS

The subjects were 151 consecutive patients (115 men and 36 women ranging in age from 41 to 82 years) who were scheduled for CABG under nonemergency conditions between October 1995 and February 1998. Carotid and intracranial arteries were examined for occlusive lesions with MR angiography. Patient demographics and risk factors including age, sex, hypertension, diabetes mellitus, hyperlipidemia, smoking habit, history of stroke, peripheral vascular disease and preoperative thromboembolic infarcts revealed by MR imaging were recorded and analyzed.

RESULTS

Cervical carotid artery stenoses of more than 50% narrowing were detected in 16.6% of the subjects, and intracranial artery stenoses of more than 50% narrowing were detected in 21.2% of the subjects. Multiple logistic regression analyses identified peripheral vascular disease and lacunar infarcts in the basal ganglia as significant and independent predictors of cervical carotid arterial stenoses. No significant predictor for intracranial arterial stenoses was identified.

CONCLUSIONS

The prevalence of extracranial carotid and intracranial artery stenosis in Japanese patients scheduled for CABG is considerably high. MR angiography is of value of identifying these patients. Preoperative evaluation of cranial arteries is recommended, particularly in patients with peripheral vascular disease and infarcts in the basal ganglia.

[Management of coronary artery disease combined with aortic stenosis: how to do with mild aortic stenosis]

A total of fourteen patients with combined operation of coronary artery bypass grafting (CABG) and aortic valve replacement (AVR) for coronary artery disease (CAD) and aortic stenosis (AS) were reviewed to evaluate the indication of the combined operation. Preoperative pressure gradient across the valve and effective orifice area were 21-89 mmHg (mean 64 mmHg), 0.5-1.9 cm2 (mean 0.92 cm2), respectively. The extent of CAD was 1-3 (mean 2.0). Fractional shortening (%FS) ranged from 13% to 43% with mean value of 28%. All patients underwent CABG and AVR. The number of grafts was 1-4 (mean 2.3) with internal thoracic artery used in 7 cases. Mechanical valves were employed for all patients except 1 case with cerebral aneurysm. There was no operative death, although low output syndrome developed in 2 cases. One had poor left ventricular function preoperatively, and the other was emergency case. Fractional shortening improved postoperatively even in two cases with preoperative %FS less than 20%, and all grafts were patent on postoperative coronary angiography. The event-free survival was 100% during 32 months of mean follow-up. Combined AVR with CABG is recommended to avoid risky secondary operation in patients of CAD and AS, even if one of which is relatively mild, because of the fact that operative and late results of the combined surgery are satisfactory.

Skeletonization and harvest of the internal thoracic artery with an ultrasonic scalpel

A new method to skeletonize and harvest the internal thoracic artery using an ultrasonic scalpel is presented. The technique is simple, safe, and minimally invasive. It is possible to obtain sufficient vessel length for anastomosis to most coronary arteries for bypass grafting.

Coronary artery bypass grafting using the "Super Pulse" dynamic pulsatile cardiopulmonary bypass device in patients with cerebrovascular occlusive disease

Patients with coronary disease complicated by severe carotid or intracranial arterial stenosis underwent coronary artery bypass graft surgery (CABG) using a novel method of dynamic pulsatile cardiopulmonary bypass (Super Pulse CPB). The Super Pulse technique can maintain the systolic pressure and systolic-diastolic amplitude in such a way that they mimic the physiologic circulation. Forty-five patients (33 males and 12 females, mean age 65.1 years) with coronary disease who had a greater than 75% stenosis of the carotid or intracranial arteries were evaluated. Evaluation was performed for the following 3 groups: 8 patients with conventional pulsatile CPB (Group I), 8 patients with conventional pulsatile CPB plus intraaortic balloon pumping (Group II), and 29 patients with Super Pulse CPB. Maximum, minimum, and mean perfusion pressures during CPB were 112.7, 53.6, and 76.9 mmHg (integrated mean), respectively, in Group III. The systolic-diastolic amplitude was significantly better than for Group I and similar to baseline pressures. No patients in Group II or Group III developed perioperative cerebral disorders or myocardial infarction, while in Group I perioperative cerebral disorders developed in 3 patients, myocardial infarction occurred in 2 patients, and 2 patients died during hospitalization. The initial performance of the Super Pulse CPB indicates excellent safety, and is useful for patients with co-morbid cerebral arterial disease.

Minimally invasive direct coronary artery bypass grafting using the gastroepiploic artery for reoperation after the Cabrol procedure

Obstruction of the right coronary ostial anastomosis is a rare late complication after composite graft replacement of the ascending aorta and the aortic valve with separate Dacron coronary grafts (Cabrol method). Occlusion at the right coronary ostial anastomosis in a 36-year-old woman with aortitis syndrome who underwent a composite graft with a Dacron coronary graft is described. She underwent a third successful operation for right coronary reconstruction by minimally invasive direct coronary artery bypass grafting technique using the right gastroepiploic artery. This approach is likely to be extremely useful in avoiding resternotomy and cardiopulmonary bypass in patients requiring coronary reoperation.

Two cases of aorto-gastrointestinal fistula

We report two cases of aorto-gastrointestinal fistula. Case 1, a 60-year-old man, suffered from repeat hematemesis. He was preoperatively diagnosed as aortoesophageal fistula with thoracic aortic aneurysm and was successfully treated by graft replacement of the aneurysm. Case 2, a 73-year-old man, presented with massive gastrointestinal bleeding, yet repeat endoscopical examination did not reveal the origin of the bleeding. He died of catastrophic hematochezia. The pathological findings at autopsy revealed an aortoduodenal fistula. These two cases suggested the importance to consider an aorto-gastrointestinal fistula in the differential diagnosis of patients presenting gastrointestinal hemorrhage.

Retrograde cerebral perfusion versus selective cerebral perfusion as evaluated by cerebral oxygen saturation during aortic arch reconstruction

BACKGROUND

Time limits for neuroprotection by retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) in aortic arch aneurysm repair or dissection are undergoing definition.

METHODS

Using near-infrared optical spectroscopy, changes in regional cerebrovascular oxygen saturation (rSO2) were compared between the two perfusion methods.

RESULTS

Immediately before cardiopulmonary bypass, baseline rSO2 was 63.9%+/-6.9% for the RCP and 66.1%+/-5.3% for the SCP group (no significant difference). As patients were core-cooled to 20 degrees C, rSO2 increased to 73.1%+/-8.8% and 74.1%+/-7.9% in the RCP and SCP groups, respectively. With circulatory arrest, rSO2 suddenly decreased. After starting cerebral perfusion, rSO2 returned to prearrest values in the SCP group but continued decreasing steadily in the RCP group, to levels below baseline after about 25 minutes. At the end of perfusion, rSO2 was 57.4%+/-12.2% for the RCP group and 71.7%+/-6.9% for the SCP group, and the ratio of rSO2 to baseline value was 0.89 for RCP and 1.08 for SCP despite a shorter brain perfusion time for RCP (38.8+/-18.0 versus 103.3+/-43.3 minutes). Three of 5 patients whose ratios of rSO2 to baseline at the end of brain protection were 0.7 or less had neurologic deficits.

CONCLUSIONS

Although SCP showed no clinically important time limitation, rSO2 continued to decrease with time during RCP. An rSO2 ratio less than 0.7 could represent a critical lower limit.

Emergency percutaneous cardiopulmonary bypass support for acute myocardial infarction

We assessed the efficacy of emergency percutaneous cardiopulmonary bypass support (PCPS) in the treatment of patients with acute myocardial infarction complicated by cardiogenic shock. Emergency PCPS was instituted in 21 consecutive patients beginning in 1991. After the stabilization of the hemodynamics, coronary reperfusion was performed by means of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. Of the seven patients with acute myocardial infarction involving either the left main or two-vessel territories, five survived more than 1 month, but only one patient remained alive and well after 20 months. The main cause of death for this group was low output syndrome. Four of 12 patients with acute left main trunkal occlusion in the catheter laboratory survived and showed a preserved cardiac function (mean followup 28.5 months). The main cause of death for this group was brain damage. Two patients with single-vessel territory acute myocardial infarction underwent PCPS to treat refractory ventricular fibrillation. Both patients were still alive and well at a 12-month followup. Percutaneous cardiopulmonary bypass support successfully stabilized the hemodynamics, allowing time to perform revascularization for all three groups of patients with life-threatening acute myocardial infarction. Recanalization was nevertheless unable to salvage the damaged myocardium in cases of prolonged ischemic time.

[Rupture of the papillary muscle after percutaneous transvenous mitral commissurotomy (PTMC)--a case report]

We experienced a rare case of the mitral regurgitation due to papillary muscle rupture after percutaneous transvenous mitral commissurotomy (PTMC). This case was a seventy years old female who underwent PTMC. The cardiac tamponade and mitral regurgitation occurred after PTMC. Pericardial drainage was done immediately, and the next day the emergency operation was required. Rupture of the posterior papillary muscle was found at the operation, and mitral valve replacement was performed. Her postoperative course was uneventful and she discharged on the 26th day after the operation. We should take the papillary muscle rupture into consideration if there are severe sub-valvular lesion and shorting of the chorda.

[A comparison of changes of cerebrovascular oxygen saturation in retrograde and selective cerebral perfusion during aortic arch surgery]

To evaluate the effect of retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) on brain protection, changes of cerebrovascular oxygen saturation (rSO2) were studied in 14 patients with aortic arch reconstruction during the procedure. The rSO2 was monitored with spectroscopy instrument (Invos 3100, Somanetics). The mean value of rSO2 measured just before cardiopulmonary bypass was 65.9 +/- 6.2% in 7 patients with RCP, and was 64.9 +/- 4.7% in 7 patients with SCP. The value of rSO2 during core cooling of cardiopulmonary bypass was increased step by step. Although RCP time with a mean of 38.9 +/- 9.7 min was statistically shorter than SCP time (80.7 +/- 45.1 min), the mean value of rSO2 during cerebral protection in RCP group was decreased from 80.3 +/- 8.1% to 63.4 +/- 10.2%, lowest 46% with a ratio of 21.1%. In contrast, the mean value of rSO2 in SCP group was well maintained from 79.9 +/- 6.5 to 75.6 +/- 6.8%, lowest 63% with a ratio of 5.4%. Although no neurological deficits were recognized after operation in both groups, rSO2 in SCP group was sustained above the control value (65% just before cardiopulmonary bypass) but rSO2 in RCP group was decreased below the control value after 35 min. So we conclude that with regard to brain protection assessed from rSO2 measured by Invos 3100 cerebral oximeter, there is no time limitation of SCP during the procedure but RCP had a limit of the duration.

[Mitral valve repair for the treatment of ischemic mitral regurgitation]

Twenty-six patients with moderate and severe ischemic mitral regurgitation due to papillary muscle dysfunction underwent mitral valve replacement (MVR) or mitral annuloplasty (MAP) using modified Kay method. Emergent operation was performed in 12 patients of whom 11 had severe congestive heart failure even under IABP, 5 had cardiogenic shock and 9 needed respiratory care with intubation preoperatively. Elective operation was performed in 14 patients of whom 6 had history of congestive heart failure and 1 had episodes of ventricular tachycardia. As intraoperative findings of mitral valve, mural annular dilatation in 84.6%, prolapse of anterior leaflet in 23.1%, papillary muscle scar in 15.4%, chordal elongation in 15.4% and chordal rupture in 3.8% were seen separately or in combination. In 22 patients MAP using modified Kay method and CABG were performed, but in 4 patients MVR was needed because of the prominent prolapse of the anterior leaflet. Fourteen patients who underwent MAP with CABG and one MVR with CABG survived. Hospital mortality was higher in emergent (58.5%) than elective operation (28.6%). In the 15 survivors, mitral regurgitation decreased below Sellers 2, pulmonary wedge pressure decreased significantly (p < 0.01) and NYHA functional class improved to I or II postoperatively. During the follow up period of 15-100 (mean 38.7 +/- 21.6) months, 2 MAP+CABG patients died suddenly, but the remaining 13 patients were in NYHA class I or II and no progression of MR was seen. These results indicated that MAP+CABG is recommendable in the treatment of ischemic mitral regurgitation due to papillary muscle dysfunction, in order to preserve cardiac function and to reduce valve related complications.

Successful surgical treatment of aortocaval fistula using cardiopulmonary bypass

Aortocaval fistula caused by rupture of an abdominal aneurysm was diagnosed before surgery and treated successfully using cardiopulmonary bypass, which effectively controlled the massive bleeding. Rupture of the false lumen of a dissecting aneurysm limited to the abdominal aorta was responsible for the aortocaval fistula. The defect of the inferior vena cava was closed with a running suture and the aneurysm replaced with a collagen-coated Y graft.

Successful surgical treatment of a pseudoaneurysm after composite graft replacement of the aortic valve and ascending aorta: report of two cases

Composite graft replacement of the ascending aorta and aortic valve has now become a safe surgical procedure; however, early and late complications still frequently occur. Anastomotic dehiscence after a composite graft replacement is one potentially lethal complication. We herein report two cases of a pseudoaneurysm caused by dehiscence of the right coronary anastomosis, and the proximal aortic anastomosis. A follow-up with an echocardiogram and computed tomography scan was found to be very useful and accurate. We thus successfully treated two cases of pseudoaneurysm using either Bentall's or Carbrol's procedures.

[Surgical repair of aortic dissection associated with compression of true lumen during retrograde perfusion--report of two cases]

Two cases of acute aortic dissection which developed compression of the true lumen due to retrograde perfusion during cardiopulmonary bypass were reported. In the first case, coronary reperfusion could not be achieved when the aortic cross-clamping was removed after Collins' method of aortic dissection. There was no blood flow from the true lumen through the aortic root while the false lumen was distended by the retrograde perfusion. After completion of antegrade perfusion through the arterial cannula inserted into the anastomosed site of the ascending aorta, coronary reperfusion was established and the heart beating could be thereby obtained. In the second case, the false lumen was gradually expanded, and the true lumen was completely obstructed by it. Reexpansion of the true lumen was achieved by initiation of antegrade perfusion through the cannula inserted into the graft replaced in the ascending aorta. Fortunately cerebral and cardiac complications were not found in both cases postoperatively. Compression of the true lumen is rare, but fatal complication that may occur during retrograde perfusion in surgical repair for aortic dissection of Stanford type A. Therefore, it is very important to replace the perfusion cannula in the true lumen of the reconstructed aorta for preventing insufficiency of coronary and cerebral circulation.

[A case of acute aortic dissection with aortic regurgitation successfully treated by postoperative ECMO]

A case of acute aortic dissection (Stanford Type A) with severe aortic regurgitation successfully treated by postoperative ECMO was reported. The patient was 41-year-old man in shock condition and was transferred to Kobe University Hospital. Chest CT scan and echocardiogram revealed acute aortic dissection with severe aortic regurgitation. An emergent operation by Collins' method and resuspension of aortic valve were carefully performed. Consequent ECMO was necessitated because of postoperative left ventricular and respiratory failure. Thereby, ECMO using heparin-coated CBAS-MAXIMA membrane oxygenator, centrifugal pump, and tubes was established by arterial cannulation via the anastomotic site of the ascending aorta to prevent the obstruction of the aortic true lumen by the false lumen which may be enlarged by retrograde perfusion via the femoral artery. Left ventricular function and pulmonary function were improved after 6 hours and 20 minutes, thus ECMO was successfully weaned without any complications.

[Closure of patent ductus arteriosus in elderly cases]

A technique for closure of patent ductus arteriosus in the elderly cases is described. We have operated on eleven adult cases of patent ductus arteriosus cases in 10 years. In five cases cardiopulmonary bypass used and in the other six cases it was not used. The cardiopulmonary bypass was used especially for the patients with pulmonary hypertension (pulmonary artery mean pressure greater than 40 mmHg), or high aged (older than 40 years) patients. No operative death have occurred in both groups, and no complication from air embolism or hemorrhage have been encountered. The technique embodies the profound hypothermia, low flow, and direct suture of the pulmonary end of the ductus arterious through a pulmonary arteriotomy. The ductus has been obstructed by using a Hegar's dilator before core cooling was started. Hegar's dilator is useful for establishing profound hypothermia and satisfactory visualization of the operative field.

Long-term results and its managements after coronary bypass surgery

Between 1970 and 1985, 221 patients with coronary artery occlusive disease underwent aorto-coronary bypass (A-C bypass) and other procedures. Among these patients, 187 had A-C bypass alone and A-C bypass in addition to correction of valvular lesions or arterialization of the coronary vein, myocardial puncture by laser. The remaining 34 had surgical corrections for myocardial infarction and its complications. Subjects were 100 patients who underwent A-C bypass alone over 6 months ago and whose follow-up study could be performed in 93 survival cases [corrected]. Subsequently, 94% of the patients have met the criteria for grade I of NYHA functional capacity and have returned to normal work at a mean of 4 years and 2 months after surgery. Improved left ventricular function has been maintained postoperatively in the patients with complete revascularization. Improved operative technique, in addition to intraoperative balloon angioplasty and onlay patch grafting, have increased the patency rate (78% in 1 mm, 94% in 2 mm of coronary diameter) of the grafts with postoperative anticoagulant therapy. On the basis of our long-term observations, coronary bypass surgery, particularly in complete revascularization, provides for significant improvement in both the quality and life expectancy of patients with severe coronary heart disease. Treadmill exercise test and magnetic resonance image (MRI) were useful, non-invasive and acceptable examinations in long-term follow up.

[Long-term result and its evaluation after aorto-coronary bypass grafting]

Since a first successful A-C bypass using saphenous vein graft was performed in 1970, eighty five patients with severe coronary heart disease were operated on in our clinic. Up to date, A-C bypass was carried out in sixty four cases, and aorto-coronary sinus bypass (Ao-Cs bypass) as an arterialization of the coronary venous system was done in one case in the group of angina pectoris. Three cases among sixty four patients who underwent A-C bypass and a case of Ao-Cs bypass died of low cardiac output syndrome postoperatively. Other two cases died of refractory arrhythmia and cardiomyopathy 6 years after surgery. The remaining fifty nine cases are doing well without any complications during follow up from ranging 2 months to 13 years (mean 3 years 4 months). Recently, no operative death was found during past 8 years with development of surgical technique and myocardial protection. Ventricular function (cardiac index, LVedp, Max LV dp/dt, EF, LVEDVI , double products at rest and during treadmill exercise test) disclosed good results especially in complete revascularization group. Graft patency had a close correlation between a diameter of the coronary artery at the anastomosis site and bypass graft flow after completion of bypass. Subsequently, a good patency rate (84%-86%) was obtained in cases with the coronary artery more than 1.5 mm in diameter. It could be concluded that A-C bypass was useful procedure to improve ventricular function as well as clinical symptoms and longevity of the life.