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M Natsuaki

Publications and source records attributed to M Natsuaki.

At least 19 recordsLinked to original sources
PubMed2004

[Novel strategy for thoracoabdomianl aortic aneurysm repair; intraoperative selective perfusion of the Adamkiewicz artery].

We report our method for delineating the Adamkiewicz artery using multidetector row computed tomography (MDCT) with selective perfusion using a distal perfusion cannula that is clinically available for off-pump coronary artery bypass (OPCAB). The tip of a distal perfusion catheter (Medtronic Quickflow, Minneapolis) designed for OPCAB was applicable for selective perfusion of the segmental arteries. The femoro-femoral venoarterial bypass was branched off into selective perfusion of the segmental arteries, using an independent roller pump and heat exchanger. Our method of visualization of the Adamkiewicz artery was MDCT scanning with injection of contrast medium directly into the proximal descending aorta: namely, "CT during aortography". Lower descending aorta to abdominal aorta (the range involving the aneurysm) was scanned in a cephalad-to-caudal direction using a detector collimation of 4 x 1.25 mm with a table speed of 9.4 mm/sec, pitch of 6, and image thickness of 1.25 mm. All images were reviewed on a workstation to investigate the continuity between the Adamkiewicz artery and its proximal segmental artery with paging, mulitplanar reformation and curved planar reformation. Distal perfusion cannulae of 2.0 mm in diameter were inserted into the respective intercostal arteries. 4-0 polyethylene sutures were placed to tourniquet the catheters. Segmental arteries were perfused with total flow of approximately 80 ml/min at a circuit pressure of 120 mmHg. Reattachment of the ninth intercostal arteries related to the Adamkiewicz artery was carried out. A total of 6 consecutive 6 patients with thoracoabdominal aortic aneurysm (TAAA) have undergone graft replacement by the methods described, since April 2002. All patients survived surgery without any neurological complications. This method is expected to minimize the ischemic time of the spinal cord and attenuate the reperfusion injury.

Aged↗
PubMed2004

Risk factors associated with perioperative myocardial damage in patients with severe aortic stenosis.

AIM: Few studies have been performed about the risk factors associated with perioperative myocardial damage in patients undergoing valve surgery for severe aortic stenosis. METHODS: To assess the prevalence of perioperative myocardial damage, we studied 103 consecutive patients with aortic stenosis. Perioperative myocardial damage (PMD) was diagnosed by both enzymatic data of peak creatine kinase iso-enzyme (CK-MB) and new appearance of electrocardiographic abnormality. PMD was noticed in 16 patients, and PMD was not noticed in 87 patients. A stepwise multiple logistic regression model was used to investigate predictors of PMD in several categorized parameters such as preoperative data, cardioplegic delivery method, and aortic clamping time. RESULTS: A multivariate analysis identified that cardioplegic delivery method, preoperative left ventricular (LV) wall thickness, and aortic clamping time were independent predictors of PMD. The incidence of PMD in the combined antegrade and continuous retrograde delivery method was significantly lower than that in antegrade delivery method (odds ratio 0.11, CI 0.02-0.61, p=0.011). The peak CK-MB value of the combined antegrade and retrograde method was significantly lower than that of the antegrade method (48+/-24 vs 71+/-50 IU/L; p=0.009). The peak lactate-dehydrogenase value of the combined method was significantly lower than that of the antegrade method (590+/-249 vs 1058+/-656 IU/L; p<0.001). The combined method decreased the incidence of PMD in patients with increased total wall thickness. CONCLUSION: Cardioplegic delivery method, LV total wall thickness, and aortic clamping time were independent predictors for PMD. Combined antegrade and continuous retrograde delivery method may be an important factor to obtain adequate myocardial protection.

Adult↗
PubMed2003

[Left atrial thrombus without mitral disease; report of a case].

A 76-year-old man was admitted to our hospital because of surgical treatment for mass in the left atrium(LA). Echocardiography and computed tomography(CT) revealed mobile mass in LA which had stalk at the left atrial appendage. It was difficult to distinguish myxoma from thrombus. LA mass has risk of sudden circulatory collapse and systemic emboli, so it is indicated for emergent operation. Mass resection with appendage was performed through the transseptal superior incision using cardiopulmonary bypass. Pathological diagnosis was thrombus. Most of LA thrombus were complicated with mitral stenosis, LA thrombus without mitral disease is rare. A few authors reported the useful of CT and echocardiography, but we could not lead to precise diagnosis from preoperative image.

Aged↗
PubMed2002

[Combined carotid endarterectomy and off-pump coronary artery bypass grafting].

Patients with angina undergoing carotid endarterectomy have a high mortality. A 74-yaer-old man who has severe carotid stenosis was performed combined carotid endarterectomy and off-pump coronary artery bypass grafting successfully. At first, carotid endarterectomy was performed with Jamieson's specially designed dissector, which allow simultaneous dissection and removal blood from the surgical field. Secondly, then off-pump CABG was performed. Skeletonized internal mammary artery was harvested with ultrasound dissector. The advantage of that the dissected artery is not only long and greater blood flow, but also less damage to sternal blood flow which prevent infection and complications. Then internal mammary artery was anastomosed to left anterior discending artery with Octopus II stabilizer. After the operation, he recovered uneventfully without neurological complication. Combined single staged carotid endarterectomy and off-pump CABG appears to be a safe method.

Aged↗
PubMed2001

Coronary endothelial damage during off-pump CABG related to coronary-clamping and gas insufflation.

OBJECTIVE: Although off-pump coronary artery bypass grafting (CABG) has been recognized less invasive than conventional CABG on cardiopulmonary bypass, off-pump CABG may be partly invasive especially to the coronary endothelium. The present study was designed to evaluate the adverse effects of coronary snaring with looped sutures and gas insufflation on the coronary endothelium. The protective efficacies on the coronary endothelium of coronary snaring with elastic sutures or humidified gas insufflation with/without heparin and dipyridamole-added were also tested. METHODS: Thirty-six mongrel dogs were used. After systemic heparinization (150 U/kg), a 5 mm longitudinal coronary incision was made with looped non-elastic monofilament sutures or elastic sutures applied proximally and distally. The incised coronary artery was exposed to non-humidified carbon dioxide, humidified carbon dioxide with lactated Ringer solution, or humidified carbon dioxide with heparin and dipyridamole-added lactated Ringer solution for 10 or 20 min in each group. After gas insufflation, the incised coronary artery was repaired, then, the coronary was reperfused. Perfusion-fixation was done for observation of the coronary endothelium by scanning electron microscopy. The adverse effect on the endothelium was graded as follows: grade 1, appeared normal; grade 2, few blood cells deposited; grade 3, many blood cells deposited; grade 4, few endothelial cells delaminated with blood cells deposited; grade 5, many endothelial cells delaminated with blood cells deposited. RESULTS: Non-elastic looping caused much more endothelial tears than elastic looping (P<0.00001). Non-humidified gas blowing for 20 min caused more endothelial cell damage than humidified gas blowing (P=0.00005). Non-humidified gas blowing for 10 min caused less damage than for 20 min (P=0.00326), but still caused more damage than humidified gas blowing (P=0.00253). Heparin and dipyridamole-added humidification reduced coronary endothelial area mottled by the deposited cells when compared with simple humidification (P=0.00120). CONCLUSIONS: Coronary snaring resulted in coronary endothelial injury, which was ameliorated by using elastic sutures instead of non-elastic sutures. Non-humidified gas insufflation made blood cells deposited and endothelial cells delaminated with time. Humidified gas insufflation attenuated these adverse effects. Heparin and dipyridamole-added humidification had potential advantage in terms of reducing deposited blood cells on the endothelium over simple humidification.

Animals↗
PubMed2000

Evaluation of postoperative cardiac function and long-term results in patients after aortic valve replacement for aortic valve disease with increased left ventricular mass.

OBJECTIVE: This clinical study was designed to evaluate the postoperative cardiac function in patients after aortic valve replacement for aortic valve disease with increased left ventricular mass. METHODS: Aortic valve replacement was performed in 117 patients using the St. Jude Medical valve. Their valve lesion was aortic regurgitation in 71, and aortic stenosis in 46. The mean value of the left ventricular mass index was 272 g/m2. The 117 patients were subdivided into 4 groups according to their preoperative left ventricular mass index-Group I (n = 35) with aortic regurgitation and a large left ventricular mass index (> or = 273 g/m2), Group II (n = 36) with aortic regurgitation and a small left ventricular mass index Group III (n = 19) with aortic stenosis and a large left ventricular mass index, and Group IV (n = 27) with aortic stenosis and a small left ventricular mass index. The cardiac function was evaluated by radionuclide ventriculography. RESULTS: In a comparative study of postoperative parameters among the 4 groups, the postoperative systolic and diastolic parameters of Group I patients were more significantly impaired compared with these parameters of the other 3 groups. The postoperative values the left ventricular mass index were significantly higher in Group I than in the other 3 groups. The 10-year survival rate was significantly lower in Group I than in the other 3 groups (30 +/- 22% in Group I). CONCLUSION: Aortic valve replacement is recommended for patients with eccentric hypertrophy in the adequate clinical phase of patients whose left ventricular mass index is less than 272 g/m2.

Adult↗
PubMed2000

Ulinastatin attenuates reperfusion injury in the isolated blood-perfused rabbit heart.

BACKGROUND: Ventricular dysfunction after long cardioplegic arrest has been observed in cardiac operations. Urinary trypsin inhibitor, also called ulinastatin, may attenuate myocardial ischemia-reperfusion injury. The present study was designed to determine the protective efficacy of ulinastatin in blood-perfused parabiotic isolated rabbit hearts as a surgically relevant model with long (4-hour) cardioplegic arrest. METHODS: Each isolated rabbit heart, with a latex balloon inserted in the left ventricle, was parabiotically blood-perfused using a modified Langendorff column. The left ventricular developed pressure, rate of pressure development, and coronary flow with a left ventricular end-diastolic pressure of 10 mm Hg were measured before ischemia and 15, 30, 45, and 60 minutes after reperfusion began (control, n = 10). Ulinastatin (15,000 U/kg) was administered to the support animal just before reperfusion began (group U-1, n = 10) or at the beginning of the extracorporeal circulation and readministered before reperfusion (group U-2, n = 10). The endothelium of the coronary artery was observed by scanning electron microscopy to evaluate the extent of endothelial ischemia-reperfusion injury. RESULTS: Ulinastatin enhanced the recovery of developed pressure in both the U-1 (p<0.05) and U-2 (p < 0.01) groups compared with the control group. Although ulinastatin given just before reperfusion (group U-1) did not enhance the recovery of the rate of pressure development or the coronary flow compared with the control, earlier administration did improve the recovery of the rate of pressure development compared with the control (U-2, p<0.05), and there was improvement of the recovery of coronary flow after 60 minutes of reperfusion (U-2, p<0.05). Scanning electron microscopy showed that ulinastatin had ameliorated coronary endothelial damage. CONCLUSIONS: Ulinastatin improved functional recovery after long cardioplegic arrest and reduced coronary endothelial injury. Administration of ulinastatin at the beginning of cardiopulmonary bypass and just before reperfusion may be useful clinically in cases requiring prolonged aortic cross-clamping.

Animals↗
PubMed2000

Successful valve-sparing in aortic root reconstruction under endoscopic guidance.

OBJECTIVE: Aortic insufficiency (AI) associated with ascending aneurysm can be corrected by valve-sparing aortic root reconstruction ('David' reimplantation, 'Yacoub' remodeling). Intraoperative endoscopic evaluation in the aortic root may help to clarify the procedure and to access competence of the preserved valve. METHODS: Following cross-clamping of the ascending aorta, an endoscopy was inserted into the proximal aortic root. Perfusion of crystalloid cardioplegia enabled the visualization of the pressure-loaded valve in the closed position. Conventional macroscopic evaluation would have overlooked valve prolapse because of a release from perfusion pressure. Valve coaptation was imaged directly before and after the valve-sparing procedure. A total of 17 patients underwent aortic root reconstruction under endoscopic guidance. Indications of the valve-sparing were determined with endoscopic findings. The degree of AI before and after the surgery was evaluated by aortography and scored (0, none; 1 trivial; 2, mild; 3, moderate; 4, severe). RESULTS: Remodeling was employed to eight patients and reimplantation to four. The other five patients were replaced with prosthetic valved-conduit. There was no early and late mortality. Before and after the valve-sparing surgery, grades of AI were significantly reduced. Three patients who underwent reimplantation procedure required late valve replacement for late progression of AI, however, none of the patients with remodeling required reoperation. CONCLUSION: Introduction of an endoscopy successfully reduced postoperative AI and clarified indications and limitations of valve-sparing aortic root operations.

Aortic Dissection↗
PubMed2000

Leukocyte-depleted reperfusion after long cardioplegic arrest attenuates ischemia-reperfusion injury of the coronary endothelium and myocardium in rabbit hearts.

OBJECTIVE: Cardiopulmonary bypass activates leukocytes, which should injure the coronary endothelium and myocardium during reperfusion especially after long cardioplegic arrest with long cardiopulmonary bypass time. The present study was designed to determine the protective efficacy of leukocyte-depleted reperfusion in blood-perfused parabiotic isolated rabbit hearts as a surgically relevant model with long cardioplegic arrest. METHODS: Each isolated rabbit heart, with a latex balloon inserted in the left ventricle, was parabiotically blood-perfused using a modified Langendorff column. The left ventricular developed pressure (DP), rate of pressure development (dP/dT), and coronary flow with a left ventricular end-diastolic pressure of 10 mmHg were measured before ischemia and after 15, 30, 45, and 60 min reperfusion after 4 h cardioplegic arrest kept at 20 degrees C (control, n=10). Leukocyte-depleted reperfusion was done in the test group (n=10). The endothelium of the coronary artery was observed by scanning electron microscopy (SEM) with percent injured area of endothelial cells measured to evaluate the extent of endothelial ischemia-reperfusion injury. RESULTS: The control hearts showed 53.3, 54.3, 48.4, and 39.0% recovery of DP compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began respectively. Leukocyte-depleted reperfusion enhanced the recovery of DP at 45 min (81.3%, P=0.0021) and 60 min (85.8%, P=0.0005) after reperfusion compared with that in the control group. The control hearts revealed 58.8%, 59.8%, 52.6%, and 43.4% recovery of dP/dT compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began, respectively. Leukocyte-depleted reperfusion also enhanced the recovery of dP/dT at 45 min (93.2%, P=0.0071) and 60 min (98.8%, P=0.0011) after reperfusion compared with that in the control group. There was also improvement of the recovery of coronary flow by leukocyte-depleted reperfusion (97.2%) compared with that in the control group (58.3%) after 60 min reperfusion (P=0.0121). Scanning electron microscopy showed that 69. 7% of coronary endothelial cells were morphologically injured in the control group. In contrast, leukocyte-depleted reperfusion prevented the extent of coronary endothelial damage with less injured area (0. 5%, P=0.0002). CONCLUSIONS: Leukocyte-depleted reperfusion improved functional recovery with reduced coronary endothelial injury after long cardioplegic arrest.

Animals↗
PubMed2000

Immediate contact hypersensitivity induced by repeated hapten challenge in mice.

An immediate reaction was investigated during repeated challenge testing for contact hypersensitivity to dinitrofluorobenzene (DNFB) in BALB/c mice. The mice were sensitized to DNFB on back skin and repeatedly challenged with the same hapten on the left ear at 1 week intervals. The ear after the 5th challenge showed biphasic responses which consisted of an immediate and a delayed-type reaction. The reactions were hapten specific. Mast cell-deficient WBB6F1 W/WV mice did not show any immediate reaction, while congenic normal mice showed both immediate and delayed-type reactions. Histologically, numerous dermal mast cells were found in the left ear of repeatedly challenged BALB/c and WBB6F1 normal mice, while there were few mast cells in the ear of WBB6F1 W/WV mice. Anti-DNP IgE antibodies were detected in BALB/c, WBB6F1 normal and W/WV mice after repeated challenge with DNFB. Intradermal injection of anti-IgE antibodies in the repeatedly DNFB-challenged ear elicited an immediate reaction. These results suggest that immediate contact hypersensitivity develops through the production of anti-DNP IgE antibodies and an increase in dermal mast cells after repeated challenge with DNFB.

Animals↗
PubMed2000

Experimental use of a compact centrifugal pump and membrane oxygenator as a cardiopulmonary support system.

Compactness and high performance are the most important requirements for a cardiopulmonary support system. The Nikkiso (HPM-15) centrifugal pump is the smallest (priming volume; 25 ml, impeller diameter; 50 mm) in clinically available centrifugal pumps. The Kuraray Menox (AL-2000) membrane oxygenator, made of double-layer polyolefin hollow fiber, has a minimum priming volume (80 ml) and a low pressure loss (65 mm Hg at 2.0 L/min of blood flow) compared with other oxygenators. The aim of this study was to evaluate the performance of the most compact cardiopulmonary support system (total priming volume: 125 ml) in animal experiments. The cardiopulmonary bypass was constructed in a canine model with the Nikkiso pump and Menox oxygenator in comparison with a conventional cardiopulmonary support system. The partial cardiopulmonary bypass was performed for 4 h to evaluate the gas exchange ability, blood trauma, serum leakage, hemodynamics, and blood coagulative parameters. The postoperative plasma free hemoglobin level of the compact cardiopulmonary system was 29.5 +/- 10.21 mg/dl (mean +/- SD), which was lower than that of the conventional cardiopulmonary system, 48.75 +/- 27.39 mg/dl (mean +/- SD). This compact cardiopulmonary system provided the advantage in terms of reduction of the priming volume and less blood damage. These results suggested the possibility of miniaturization for the cardiopulmonary bypass support system in open-heart surgery in the near future.

Animals↗
PubMed1999

Early valve failure after aortic valve-sparing root reconstruction.

Aortic valve-sparing root reconstructive surgery has been widely adopted to improve the patient's quality of life. We experienced a patient who required reoperation for progressive aortic regurgitation 17 months after the initial operation of valve-sparing root reconstruction with the reimplantation method in acute aortic dissection. In this study, we were concerned with valve durability because of the absence of sinuses of Valsalva in the new aortic root and the need for careful follow-up after this procedure.

Aortic Valve↗
PubMed1999

Argatroban as a potential anticoagulant in cardiopulmonary bypass-studies in a dog model.

Argatroban is a selective thrombin inhibitor synthesized in Japan. Argatroban, which has a high affinity for thrombin, and markedly inhibits thrombin-induced reactions, has been used in patients with artherosclerosis obliterans. The efficiency of argatroban, instead of heparin, as an anticoagulant in dog models of cardiopulmonary bypass was explored. In the first study, argatroban was administered as a bolus plus infusion for 1 h during cardiopulmonary bypass at doses of 1.0 mg + 10 microg/kg per min, 2.0 mg + 10 microg/kg per min and 3.0 mg + 10 microg/kg per min (n = 2 per group). Activated clotting time and arterial gas analyses were performed beforehand and 10 min thereafter. In the second study, there were four groups. In the first group (n = 5), no coated extracorporeal circuit was used and heparin (2 mg/kg) was used as an anticoagulant. In the second group (n = 5), a coated extracorporeal circuit was used and heparin was used (2 mg/kg) as an anticoagulant. In the third group (n = 3), no coated extracorporeal circuit was used and argatroban (2.0 mg + 10 microg/kg per min) was used as an anticoagulant. In the fourth group (n = 5), a coated extracorporeal circuit was used and argatroban was used (2.0 mg + 10 microg/kg per min) as an anticoagulant. All animals were perfused for 120 min at 40 ml/kg per minute. Platelet count, activated clotting time, thrombin-antithrombin III complex, antithrombin III, fibrinogen, fibrinogen degradation products and C3a were measured to evaluate platelet, coagulofibrinolytic and the complement system. Activated clotting time values and the effect of argatroban during cardiopulmonary bypass indicated a dose-dependent response. The next highest dosing group (2.0 mg + 10 microg/kg per minute) had activated clotting time values of 250-300 seconds during cardiopulmonary bypass, and fell after reaching near-normal levels within 60 minutes. No clots were noted in the extracorporeal circuit. The argatroban group showed lower levels in their coagulofibrinolytic system compared with the heparin group. The platelet count remained at a high level in the argatroban group. It is concluded that the combination of heparinized cardiopulmonary bypass circuits, and the use of argatroban as an anticoagulant, is safe and reduces the activation of coagulation and fibrinolytic systems and preserves platelet count.

Animals↗
PubMed1999

[A report of 4 cases of aortic operation using open proximal anastomosis under the hypothermic circulatory arrest and left lateral exposure].

Four cases of aortic operations using open proximal anastomosis (OPA) under the hypothermic circulatory arrest (HCA) and left lateral approach (LLA) are reported. Three of 4 cases had extensive aortic disease from distal arch to descending thoracic aorta (Stanford type B chronic aortic dissection, double false aneurysms, and double true aneurysms). Another one case had ruptured aneurysm of thoracic aorta. LLA should have been selected in all cases, however, aortic proximal cross-clamp was impossible in them, because of giant pseudolumen, diseased lesion of aortic arch, hemothorax followed rupture of aneurysm. Therefore OPA under the HCA was performed. There were no complication associated with HCA, bleeding, neurological deficiency and respiratory dysfunction. We conclude that, although the HCA may have some problems, if there is the proper indication, OPA under the HCA is useful method at aortic operation for difficult aortic disease.

Adult↗
PubMed1998

Reversibility of cardiac dysfunction after valve replacement in elderly patients with severe aortic stenosis.

BACKGROUND: The role of aortic valve replacement for aortic stenosis has not been fully defined in terms of the postoperative reversibility of cardiac dysfunction and pulmonary hypertension in elderly patients. METHODS: Cardiac function, assessed by radioisotope ventriculography and catheterization data, was evaluated before and after operation, and their results were compared between preoperative and postoperative data in each group of younger patients (<69 years, group I, n = 29) and elderly patients (> or =70 years, group II, n = 21). RESULTS: One month postoperatively the peak ejection rate determined by radioisotope ventriculography improved significantly in comparison with the preoperative value in elderly patients (preoperatively, 228 +/- 38 versus postoperatively, 319 +/- 116% end-diastolic volume per second, p < 0.05), although their preoperative peak ejection rate was severely depressed. The postoperative peak filling rate of the elderly group was not completely reversible to almost normal value, whereas that of the younger group was completely reversible. Early diastolic peak filling rate (one-third peak filling rate) was not reversible in both two groups. Pulmonary hypertension in the elderly patients was reversible to postoperative almost normal pulmonary artery pressure despite the severity of aortic stenosis (systolic pulmonary artery pressure preoperatively, 37 +/- 16 mm Hg versus postoperatively, 25 +/- 5 mm Hg, p < 0.02; diastolic pulmonary artery pressure preoperatively, 15 +/- 6 mm Hg versus postoperatively, 10 +/- 4 mm Hg, p < 0.05). CONCLUSIONS: Both cardiac dysfunction, reflected by reduction of peak ejection rate, and pulmonary hypertension in elderly patients with severe aortic stenosis were reversed, reaching almost normal values 1 month after operation.

Aged↗
PubMed1998

Hemodynamics after aortic valve replacement with St. Jude Medical valve for patients with small aortic annulus and severe left ventricular hypertrophy.

BACKGROUND AND AIMS OF THE STUDY: Cardiac function after aortic valve replacement (AVR) for patients with small aortic annulus and increased left ventricular (LV) wall thickness has not been clearly defined. The study aim was to examine a potential relationship between postoperative catheterization data (or radionuclide LV cardiac function) and the size of the aortic valve ring of a small St. Jude Medical prosthesis. METHODS: Sixty-one patients with small prosthesis (< or = 23 mm) were allocated to three groups based on the diameter of the native aortic annulus or aortic valve ring of the prosthesis (group I, 19 mm; group II, 21 mm; group III, 23 mm). Pre- and postoperative cardiac function was evaluated from catheterization data and radioisotope (RI) ventriculography. RESULTS: There were no significant inter-group differences in preoperative pulmonary artery pressures (PAPs), total pulmonary resistance (TPR), LV ejection fraction, peak ejection rate (PER) and peak filling rate (PFR). The mean postoperative PAPs and TPR of group I were significantly elevated in ICU compared with those of groups II or III (PAP: group I, 20+/-5; group II, 17+/-4; group III, 14+/-4 mmHg; p <0.01. TPR: group I, 505+/-268; group II, 316+/-134; group III, 276+/-125 dynes.s.cm-5; p <0.05). Postoperative PAPs and TPR of group I at one month after surgery were decreased, and no significant difference was found between the three groups. Cardiac function by RI study showed that postoperative PER and PFR improved in all three groups compared with the preoperative values. CONCLUSIONS: Postoperative reversibility of PAPs and improvement of PER and PFR in patients with a prosthesis of 19 mm or 21 mm showed that a small-sized aortic SJM valve had hemodynamic advantages. However, careful postoperative management in the ICU must be applied to patients with a small aortic annulus of 19 mm and severe concentric hypertrophy.

Aged↗
PubMed1998

[Reoperation after aortic valve replacement and root reconstruction].

Between 1984 and 1997, 127 patients in our institution underwent single aortic valve replacement (AVR) with the St. Jude Medical valve (group S) and 11 patients with a porcine pericardial valve (group T). In the same period, 45 patients underwent aortic root reconstruction, among which 39 patients underwent the Bentall procedure using Carrel patch coronary reanastomosis (group B). The other 6 patients were treated with valve-sparing aortic root reconstruction (group V), among which the reimplantation method was used in 4 patients and the remodeling method in 2. The mean and total follow-up periods of the AVR and aortic root reconstruction groups were 6.9 +/- 1.9 year/735 patient-years and 4.9 +/- 3.9/years/196 patient-years respectively. The actuarial overall survival rates in group S and T at 10 years were; 73.8 +/- 7.0% and 85.7 +/- 13.0%, respectively The probabilities of freedom from reoperation at 12 years in group S and T were 97.7 +/- 2.3% and 62.5 +/- 21.3%, respectively. Only one patient in group S required reoperation because of valve thrombosis, while 2 patients in group T underwent reoperation for prosthetic valve endocarditis. The actuarial overall survival rate after aortic root reconstruction at 10 years was 62.6 +/- 9.6%, while that of patients with acute aortic dissection and those who did not were 44.4 +/- 15.7% and 71.7 +/- 11.5%, respectively. The event-free rate at 12 years after aortic root reconstruction (group V+B) was 79.1% +/- 20/9%. The reason for reoperation in the 2 patients who underwent the Bentall procedure were prosthetic valve endocarditis in one and psuedoaneurysm at the right coronary anastomosis in the other. The reason for reoperation in one patient who formed a pseudoaneurysm was likely due to an oversized conduit hole for the Carrel patch coronary anastomosis. One patient in whom the native valve was preserved using the David reimplantation procedure required reoperation because of valve degeneration 17 months after the initial surgery, possibly due to valve rubbing on the vascular conduit because of a modified geometry of the Valsalva sinuses. In conclusion, because of the low rate of long-term mortality and reoperation, the St. Jude Medical valve is an excellent prosthesis for AVR. AVR with a porcine pericardial valve yields favorable results in terms of the low long-term mortality although the incidence of reoperation remains high. Aortic root reconstruction with the Bentall procedure using the Carrel patch method yields acceptable results in terms of long-term mortality and low rate of reoperation, although acute aortic dissection is an incremental preoperative risk factor. The early results of aortic valve-sparing root reconstructive surgery are encouraging, with excellent clinical outcomes and patient quality of life. Nevertheless, the indications for the procedure must be carefully considered.

Aorta↗