Biomedical subjects

Munetaka Masuda

Publications and source records attributed to Munetaka Masuda.

At least 19 recordsLinked to original sources

PubMed2006

Prognostic value of the sixth edition AJCC/UICC TNM classification for differentiated thyroid carcinoma with extrathyroid extension.

CONTEXT: The prognostic value of the sixth edition AJCC/UICC TNM classification is currently unclear. OBJECTIVE: The aim was to evaluate the prognostic value of the sixth edition. DESIGN AND PATIENTS: We retrospectively assessed 354 primary differentiated thyroid carcinomas (77 men and 277 women; age, 51.2 yr; follow-up, 107.6 months) between 1964 and 2003. Sixty percent of patients underwent lobectomy, 40% underwent subtotal/total thyroidectomy, and only 2% were given radioiodine. There were 153, 104, 86, and 11 patients in fifth stages I, II, III, and IV, and 175, 76, 14, 68, 10, and 11 patients in sixth stages I, II, III, IVA, IVB, and IVC, respectively. RESULTS: New T1-3 had no significant influence. In Cox proportional hazard analysis, T4a and T4b were significantly related to disease-specific survival (DSS). We separately analyzed 68 patients (age 45 yr or older) with extrathyroid extension. These T4 (fifth) tumors were reclassified as 6 T3, 52 T4a, and 10 T4b tumors. The 10-yr DSS rates were 100, 69.3, and 10.0% for T3, T4a, and T4b, respectively. T4b exhibited worse prognoses compared with T4a (P < 0.0001; hazard ratio, 10.1; 95% confidence interval, 4.1-25.3). Stages I and II in both editions achieved favorable prognoses. The 10-yr DSS rates were 67.0 and 27.3% in fifth stages III and IV, and 100, 74.5, 10.0, and 27.3% in sixth stages III, IVA, IVB, and IVC, respectively. DSS curves differed significantly between all sixth TNM stages (P < 0.0001). CONCLUSION: The sixth edition more accurately predicts different outcomes according to the revised criteria for the degree of extrathyroid extension.

Female↗

PubMed2006

The logistic EuroSCORE predicts the hospital mortality of the thoracic aortic surgery in consecutive 327 Japanese patients better than the additive EuroSCORE.

OBJECTIVE: Risk stratification in thoracic aortic surgery is a topic of major interest. Recent studies have shown the European System for Cardiac Operative Risk Evaluation (EuroSCORE) to be an extremely useful and reliable risk stratification score and also a good indicator of quality of care in cardiac surgery. The purpose of this study was to evaluate the significance of the additive and logistic EuroSCOREs in patients undergoing surgery on the thoracic aorta in Japan. METHODS: We calculated the predicted mortality according to the additive and logistic EuroSCORE algorithms in 327 consecutive patients who underwent surgery of the thoracic aorta during a 30-year period (between 1976 and 2005). We compared the score validity between the two algorithms and also evaluated the score validity for the patients who underwent thoracic aortic surgery. The score validity was assessed by calculating the area under the receiver operating characteristic (ROC) curve. RESULTS: The overall in-hospital mortality was 13%. The area under the ROC curve was satisfactorily high for the additive (0.68, 0.73, 0.73) as well as the logistic EuroSCORE (0.69, 0.74, 0.75) in the patients who underwent thoracic aortic surgery during 30-, 20-, and 10-year periods, respectively. The actual mortality was 7% (Group 1; an additive EuroSCORE of 3-6), 16% (Group 2; 7-11), and 37% (Group 3; >12). The mortality expected by the additive and logistic EuroSCORE in the three different risk groups were (5%, 9%, 19%) and (5%, 14%, 43%), respectively. Namely, the mortality expected by the logistic EuroSCORE perfectly matched with the actual mortality in any of the three risk groups. In contrast, the mortality expected by the additive EuroSCORE tended to dissociate when the number of risks increased. Significant difference was observed between the observed mortality and the mortality expected by the additive EuroSCORE algorithm in the high-risk group (p=0.0473). CONCLUSIONS: Although both the additive and the logistic EuroSCORE reliably predicted the overall operative mortality for thoracic aortic surgery in 327 Japanese patients, the logistic EuroSCORE better matched with the actual mortality in the operative risk especially in the high-risk group.

Aged↗

PubMed2006

Modified Damus-Kaye-Stansel procedure using aortic flap technique for systemic ventricular outflow tract obstruction in functionally univentricular heart.

Damus-Kaye-Stansel procedure is a useful method to relieve the systemic ventricular outflow tract obstruction in functionally univentricular heart. Regurgitation of pulmonary valve and recurrence of systemic ventricular outflow obstruction are the major concerns at the late phase of this procedure. Modification of original Damus-Kaye-Stansel procedure that can prevent the use of prosthetic materials is evaluated. The modified Damus-Kaye-Stansel procedure using aortic flap technique was performed in eight patients with functionally univentricular heart. Patients' ages ranged from 3 to 28 months (mean 14 months). Follow-up period was 37 months as a mean (9-71 months), and the follow-up was complete. There was no operative mortality and no late death. In addition, there was no recurrence of systemic ventricular outflow tract obstruction throughout the follow-up period. Regurgitation of the pulmonary valve estimated by echocardiography at the latest follow-up was none to trivial in seven patients and mild in one. The modified Damus-Kaye-Stansel procedure using aortic flap technique is a safe, useful and reproducible technique to solve systemic ventricular outflow tract obstruction in functionally univentricular heart, and it can be an alternative for original technique or the so-called double-barrel modification.

Anastomosis, Surgical↗

PubMed2006

Prostaglandin E1 attenuates impairment of cellular immunity after cardiopulmonary bypass.

OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.

Aged↗

PubMed2006

Surgical experience of cardiac tumors: early and late results.

PURPOSE: Cardiac tumors include benign and malignant neoplasms that arise within the cardiac chambers or myocardium. This study summarizes our surgical experiences with cardiac tumors. METHODS: Between 1975 and 2003, 51 patients with cardiac tumors were surgically treated. RESULTS: Myxomas. Forty-seven cardiac myxomas were excised in 46 patients with an average age of 51.7 +/- 18 years. The preoperative symptoms included congestive heart failure (37%) and embolism (30%). The incidence of preoperative embolization was significantly higher in the gelatinous and lobated myxomas than in the solid and smooth form (P = 0.017). The early mortality rate was 2.2%. Although the late mortality rate was 9.7%, no patients died from cardiological causes (mean follow-up, 11.2 years). Only 1 patient required surgery for recurrence. Benign nonmyxomatous tumors. Three patients with a mean age of 26.3 +/- 19.0 years showed benign nonmyxomatous tumors. There were no perioperative or late deaths. Malignant tumors. Two patients were diagnosed to have malignant tumors and although there was no perioperative death, both died postoperatively within 6 months. CONCLUSIONS: Cardiac myxomas and nonmyxomatous benign cardiac tumors show excellent results after a surgical excision, with a low morbidity and mortality. A surgical resection should thus be considered as a treatment option for patients with malignant tumors.

Adult↗

PubMed2006

Successful mitral valve repair for active infective endocarditis accompanied by anorexia nervosa.

Infective endocarditis of the mitral area accompanied by anorexia nervosa is extremely rare. A 34-year-old Japanese woman presented with high fever and a heart murmur that had developed over the previous 2-month period. Echocardiography revealed mitral regurgitation and vegetation attached to the anterior mitral leaflet, which had markedly prolapsed to the left atrium. We removed the vegetation with a small part of the anterior mitral leaflet and successfully repaired the mitral valve. The patient showed good recovery, and the mitral regurgitation and left ventricular chamber size had satisfactorily decreased at 2 months after the operation.

Adult↗

PubMed2006

Minor infection encouraged by steroid administration during cardiac surgery.

The aim of this study was to investigate whether steroid administration would increase the risk of postoperative infection. Sixty adults who underwent elective cardiac surgery under cardiopulmonary bypass were prospectively randomized into two groups. Thirty-one patients received hydrocortisone (50 mg x kg(-1)) before and after cardiopulmonary bypass, the other 29 served as controls. Various hemodynamic and pulmonary measurements were obtained perioperatively, and the white blood cell counts and levels of C-reactive protein were checked up to the 14(th) postoperative day. Steroid administration did not have any favorable effects during the perioperative period. Re-administration of antibiotics was needed in 7 patients (22.6%) after the 7(th) postoperative day in the steroid group, and in 3 (10.3%) in the control group. The peak white cell counts and C-reactive protein levels after the 7(th) postoperative day were significantly higher in the steroid group. Steroid administration offered no clinical benefit to patients undergoing cardiac surgery with cardiopulmonary bypass, and it may encourage minor infections in the late postoperative period.

Aged↗

PubMed2006

Impact of atrial septal defect closure on right ventricular performance.

BACKGROUND: Atrial septal defect (ASD) closure is one of the most representative cardiac operations, but there have been few assessments of right ventricular (RV) performance during the perioperative period. METHODS AND RESULTS: Using transesophageal echocardiography with automated border detection system, the RV pressure - area (P-A) loops were measured in 6 patients immediately before and after an ASD closure. Multiple RV P-A loops obtained by the inferior vena cava occlusion technique were used to evaluate end-systolic maximal elastance (Ees), preload recruitable stroke work (MEW), external work (EW) and the systolic P-A area (PAA). Ees and MEW are indices of contractility, and PAA represents the total mechanical energy. RV Ees and MEW did not change after the operation (from 3.36 +/- 2.20 to 3.70 +/- 2.04 mmHg/cm2, p = 0.4; and from 10.3 +/- 5.0 to 10.5 +/- 4.5 mmHg, p = 0.8, respectively), whereas EW and PAA were significantly reduced (from 121.4 +/- 77.4 to 48.7 +/- 26.6 mmHg/cm2, p < 0.05; and from 274.8 +/- 212.8 to 92.7 +/- 52.8 mmHg/cm2, p < 0.05, respectively). ASD closure reduced the EW and total mechanical energy of the right ventricle without influencing contractility. CONCLUSIONS: These results indicate that ASD closure preserved RV function and reduced RV myocardial oxygen consumption. Assessment of the RV P-A relationship in the operating room demonstrates the beneficial effects of ASD closure on RV performance.

Adult↗

PubMed2005

A comparative study of cardiac preservation with Celsior or University of Wisconsin solution with or without prior administration of cardioplegia.

BACKGROUND: We have previously reported the cardiac functional and metabolic benefits of administration of extracellular-type cardioplegia before preservation with University of Wisconsin solution. Celsior solution was designed to be used both as an arresting solution and a storage solution for heart transplantation. The objective of the present study is to compare cardiac function of hearts arrested and preserved with Celsior solution to hearts arrested with cardioplegia followed by preservation with UW solution. METHODS: Rabbit hearts were divided into 4 groups: in the Celsior group, hearts were arrested and preserved with Celsior solution; in the C-Celsior group, hearts were arrested by an extracellular-type cardioplegia and preserved with Celsior solution; in the UW group, hearts were arrested and stored in University of Wisconsin solution; and, in the C-UW group, hearts were arrested with extracellular-type cardioplegia and stored in University of Wisconsin solution. After 6 hours of preservation, cardiac function was measured using modified Frank-Starling curves in the isolated blood-perfused working heart. RESULTS: Cardiac function in the Celsior group was inferior to that in both the C-UW group and UW group. The C-Celsior group demonstrated inferior cardiac function compared with the Celsior group (p < 0.01), whereas no significant difference was observed between the C-UW and UW groups. CONCLUSIONS: Celsior solution did not surpass UW solution regardless of the use of cardioplegia. Further studies are required to develop optimal solution for use as both an arresting solution and a storage solution.

Adenosine↗

PubMed2005

Surgical application for a prolapse of the anterior mitral leaflet by replacing artificial chordae with polytetrafluoroethylene grafts.

PURPOSE: There are an increasing number of reports concerning mitral valve repair by a reconstruction of the chordae tendinae using expanded polytetrafluoro-ethylene (PTFE) sutures. However, little information is available about extended application or results of this technique for an extended prolapse of the anterior mitral leaflets. METHODS: Between July 1991 and August 2003, 28 patients with moderate to severe mitral regurgitation as a result of a prolapse of anterior leaflets (age range, 15-73 years) underwent mitral valve repair by reconstruction of the artificial chordae with 4-CV expanded polytetrafluoroethylene sutures without a leaflet resection. Either Kay's suture technique or ring annuloplasty was also performed to correct annular dilatation in all patients. RESULTS: No operative death or late mortality was observed. The prolapsed segment, which was successfully repaired, was within 33% of the anterior mitral leaflet (AML) in 6 patients, from 33% to 50% in 5, from 50% to 99% in 11, and 100% in 6 patients. Before discharge, immediate postoperative echocardiography showed less than moderate mitral regurgitation in 28 of 28 patients. The follow-up, consisting of a clinical examination and serial echocardiograms, was complete in all cases and the mean follow-up period was 80.6 months (range, 12-146). There were two failures that required a reoperation because of a worsening mitral regurgitation and hemolytic anemia (elongation of anchored side of papillary muscle). The other two patients required mitral valve replacement due to a progressive regression of the left ventricular function, although the regurgitation worsened from a mild level to a moderate one. When the reoperated patients were excluded from the following data, the degree of mitral regurgitation, estimated by echocardiography performed at recent follow-up period, was none in 10 patients, trivial in 13 patients, and mild in 1 patient. In addition, the systolic and diastolic dimensions of the left ventricle decreased significantly (P < 0.01). CONCLUSIONS: The replacement of artificial chordae was not complicated and it seemed to help to preserve a good relationship among leaflet tissues, chordae, and papillary muscles. We therefore suggest that the extensive use of PTFE artificial chordae appears to be a promising procedure for the repair of all kinds of mitral lesions causing mitral regurgitation.

Adolescent↗

PubMed2005

A 10-year experience with the Carbomedics cardiac prosthesis.

BACKGROUND: There are few reports on the long-term results of Carbomedics prosthetic heart valves. METHODS: Five hundred five patients who underwent valve replacement with this prosthesis in the aortic or mitral position were chosen for this study. Patients' mean age was 57 years. There were 173 aortic (AVR), 253 mitral (MVR), and 79 double (DVR) valve implants. The mean follow-up was 5.1 years, and cumulative follow-up was 2,590 patient-years with an overall follow-up rate of 99.2%. RESULTS: The early mortality rate for the total population was 2.8% (AVR 1.2%, MVR 3.6%, DVR 3.8%). Actuarial freedom from thromboembolism at 10 years was 81.8% +/- 5.1%, 85.7% +/- 3.2%, and 88.8% +/- 6.8% for AVR, MVR, and DVR, respectively. At 10 years, 92.7% of AVR, 85.4% of MVR, and 94.7% of DVR patients were free of valve-related death. Overall survival rate at 10 years was 77.6% +/- 4.6%, 71.8% +/- 4.2%, and 81.3% +/- 5.8% for AVR, MVR, and DVR, respectively. The linearized rate of thromboembolism was 1.45%/patient-year, 1.78%/patient-year, 0.67%/patient-year; of major bleeding events, 0.52%/patient-year, 0.85%/patient-year, 0.45%/patient-year; of valve thrombosis, 0%/patient-year, 0.25%/patient-year, 0%/patient-year; of prosthetic valve endocarditis, 0.1%/patient-year, 0.25%/patient-year, 0.22%/patient-year; and of all reoperations, 0.31%/patient-year, 0.93%/patient-year, 1.1%/patient-year for AVR, MVR, and DVR, respectively. CONCLUSIONS: The Carbomedics prosthetic heart valves showed comparable or even better results than those of other mechanical valves with respect to morbidity and mortality. These results may justify the use of Carbomedics valves as one of the mechanical heart valves.

Adult↗

PubMed2005

Successful treatment of tachycardia-induced cardiomyopathy with LVAD in a 12-year-old boy.

Tachycardia-induced cardiomyopathy is an unusual cardiac disease that is life-threatening if tachycardia is not controlled. We report a 12-year-old boy who suffered from ectopic left atrial tachyarrhythmia that was refractory to medications and caused tachycardia-induced cardiomyopathy with severe heart failure. The patient required a left ventricular assist device (ABIOMED BVS5000 [ABIOMED Inc, Danvers, MA]) as a bridge to recovery. Tachycardia was finally controlled with flecainide while the patient was on left ventricular assist device support. The device was successfully explanted after 28 days of support. The temporary use of a left ventricular assist device was necessary to maintain a good hemodynamic status during the treatment of pharmacological refractory tachycardia, and it allowed a successful bridge to recovery.

Anti-Arrhythmia Agents↗

PubMed2005

Limitation of venoarterial bypass. Early predictor and optimal conversion.

Conversion from venoarterial bypass to a ventricular assist device may be lifesaving for patients with severe heart failure, but the criteria for conversion have not yet been established. Forty patients who underwent venoarterial bypass for cardiac failure were reviewed. Of these, 18 (45%) could be weaned from venoarterial bypass, and 11 survived for more than 30 days after weaning (survival rate, 27.5%). Liver dysfunction, renal dysfunction, and the need for left-sided cardiac venting were risk factors for mortality. The appearance of patient's own cardiac pulse wave within 24 hours after the introduction of venoarterial bypass was a good indication for weaning. Delayed appearance of the cardiac pulse wave was considered to be a risk factor for death. According to these indices, conversion from venoarterial bypass to a ventricular assist device should be considered to prevent deterioration in the function of systemic organs.

Adult↗

PubMed2004

Does Down syndrome affect the long-term results of complete atrioventricular septal defect when the defect is repaired during the first year of life?

BACKGROUND: Down syndrome is known to affect the natural history of complete atrioventricular septal defect. We analyzed whether Down syndrome affect the long-term results of complete atrioventricular septal defect when the defect is repaired during the first year of life. METHODS: Repairs of complete atrioventricular septal defect were performed in 64 infants. Thirty-four infants were associated with Down syndrome, while the other 30 were non-Down patients. RESULTS: Complete follow-up rate was 95% with mean follow-up period of 99+/-47 months (maximum 169 months) in Down patients and 80+/-64 months (maximum 213 months) in non-Down patients. There was one operative death in each group (mortality rate of 2.9% in Down patients and 3.3% in non-Down patients), and three patients died at the late phase (one in Down patients and two in non-Down patients). Five patients underwent re-operation due to postoperative left atrioventricular valve regurgitation (one in Down patients and four in non-Down patients). Freedom from re-operation for left atrioventricular valve regurgitation and actuarial survival rate at 13 years were 96+/-4 and 94+/-4% in Down patients and 85+/-7 and 90+/-5% in non-Down patients (not significantly different). CONCLUSIONS: Down syndrome does not affect the long-term results of complete atrioventricular septal defect when the defect is repaired during the first year of life.

Age Factors↗

PubMed2004

Mechanical cardiac support system for patients with postcardiotomy cardiogenic shock: analysis of risk factors for survival.

OBJECTIVE: Mechanical cardiac support system (MCSS) has been used for adult patients in postcardiotomy cardiogenic shock and has been shown to provide excellent oxygenation and hemodynamic support. However, MCSS has a number of disadvantages that include high incidence rate of complications (e.g. stroke, bleeding) and limited duration of sufficient support. The objective of this study is to identify perioperative and postoperative factors for survival in patients having MCSS. METHODS: From January 1991 to April 2001, MCSS has been applied to 22 adult patients in postcardiotomy cardiogenic shock. These patients' charts were retrospectively reviewed. RESULTS: Of 22 patients, 9 patients (41%) were successfully weaned, and 6 (27%) were hospital survivors. The duration of assist ranged from 21 to 211 hours (median 66 hours). In 7 (78%) out of 9 patients who could be weaned from MCSS, MCSS were required for less than 3 days. Major complications were reexploration for bleeding (18%), leg ischemia (45%), renal dysfunction (77%), liver dysfunction (59%), infection (31.8%), hypoxia due to lung dysfunction (36%) and cerebral dysfunction (41%). pH, base excess, HCO3-, urine output, transfused platelets at first 24 hours of MCSS and preoperative body surface area were significant predictors for survival. CONCLUSION: The indices of insufficient hemodynamic support such as progression of acidosis or poor urine output are significant predictors for early death. Early conversion from MCSS to long-term assist device, such as left ventricular assist device, should be considered when these factors are associated with poor cardiac recovery.

Acidosis↗

PubMed2004

Late results after mitral valve replacement with bileaflet mechanical prosthesis in children: evaluation of prosthesis-patient mismatch.

BACKGROUND: Mechanical prosthesis is the choice of valve at the mitral position in children, although re-replacement of prostheses because of prosthesis-patient mismatch is almost inevitable when prostheses were implanted in small children. The methods to predict prosthesis-patient mismatch as a result of patients' somatic growth or pannus formation in children by noninvasive methods have not been well established. METHODS: Thirty-two children underwent mitral valve replacement with 37 bileaflet mechanical prostheses (26 St. Jude Medical prosthetic valves, and 11 CarboMedics prosthetic valves) and were followed up a mean of 6.8 years (maximum 18.3 years) with a complete follow-up rate of 94%. RESULTS: There were no operative deaths and 5 late deaths. Re-replacement of mitral valve because of prosthesis-patient mismatch was required in 5 patients. Freedom from valve-related events and re-replacement of mitral valve at 15 years were 32% +/- 23% and 54% +/- 18%, respectively. Actuarial survival rate was 63% +/- 19% at 15 years. Prosthetic valve orifice area index (manufactured geometric prosthetic valve area divided by patient's body surface area) was well correlated with maximum transprosthesis flow velocity estimated by Doppler echocardiography during follow-up, whereas valve orifice area index had no significant correlation with pulmonary artery wedge pressure assessed by cardiac catheterization. Maximum transprosthesis flow velocity had a significant correlation with pulmonary artery wedge pressure. CONCLUSIONS: Valve orifice area index itself was not a reliable index to predict prosthesis-patient mismatch. Maximum transprosthesis flow velocity was a useful index to predict pulmonary artery wedge. Invasive cardiac catheterization to determine re-replacement of the prosthesis should be considered when maximum transprosthesis flow velocity exceeds 270 cm/s.

Adolescent↗

PubMed2004

Extensive use of polytetrafluoroethylene artificial grafts for prolapse of posterior mitral leaflet.

BACKGROUND: There are an increasing number of reports concerning mitral valve repair by means of reconstruction of the chordae tendinae with expanded polytetrafluoroethylene (e-PTFE) sutures. However little information is available about extended application or results of this technique for extended prolapse of posterior mitral leaflets. METHODS: Between March 1994 and December 2000, 22 patients with moderate-to-severe mitral regurgitation (MR) as the result of a prolapse of posterior leaflets (age range, 39-73 years) underwent mitral valve repair by means of reconstruction of artificial chordae with 4-CV e-PTFE sutures without leaflet resection. Either Kay's suture or ring annuloplasty was also performed to correct annular dilatation in all patients. RESULTS: No operative death or late mortality was observed. Before discharge immediate postoperative echocardiography indicated less than moderate MR in 20 out of 22 patients. The follow-up was complete in all cases by clinical examination and serial echocardiograms and the median follow-up period was 87 months (range 24-108). There were two failures that required reoperation because of unsuccessful repair and worsening MR (elongation of the anchored side of the papillary muscle). When the reoperated patients were excluded from the follow-up data, the degree of MR, estimated by echocardiography that was performed at a recent follow-up period, was nonexistent in 6 patients, trivial in 10 patients, and mild in 4 patients. The systolic and diastolic dimensions of the left ventricle decreased significantly (p < 0.01). CONCLUSIONS: Replacement of the artificial chordae was not complicated and seemed to preserve favorable relationships among leaflet tissues, chordae, and papillary muscles. We therefore suggest that the extensive use of PTFE artificial chordae seems to be a promising procedure regarding the repair of many kinds of mitral lesions causing MR.

Adult↗

PubMed2004

Impaired endothelial function of the umbilical artery after fetal cardiac bypass.

BACKGROUND: Recently, endothelial dysfunction as a result of fetal cardiac bypass has been reported. Here, the effect of fetal cardiac bypass on the endothelial function of the umbilical artery was investigated by a tension study. METHODS: Fourteen fetal lambs were divided into a control group (n = 7) and a pump group (n = 7). In the pump group, cardiac bypass was maintained for 30 minutes using a low-volume priming circuit with a centrifugal pump. Hemodynamic measurements and blood gas analyses were performed before, during, and 30 and 60 minutes after cardiac bypass. The umbilical artery was harvested 60 minutes after cessation of cardiac bypass. Endothelium-dependent relaxation (bradykinin, calcium ionophore A23187) and endothelium-independent relaxation (sodium nitroprusside) were measured after smooth muscle contraction by 60 mmol/L potassium or serotonin and compared between the two groups. RESULTS: The umbilical artery flow and aortic pressure of the fetus were significantly decreased at 30 and 60 minutes after cardiac bypass. Hypoxia and hypercapnia were recognized during and after cardiac bypass. Metabolic acidosis progressed during and after cardiac bypass. Endothelium-dependent relaxation was impaired in the pump group compared with the control group (bradykinin: 43.6% +/- 6.4% in the control group, 18.9% +/- 2.5% in the pump group, p < 0.01; A23187: 37.8% +/- 4.6% in the control group, 19.6% +/- 3.9% in the pump group, p < 0.01). Meanwhile, endothelium-independent relaxation was preserved in both groups. CONCLUSIONS: Fetal cardiac bypass caused endothelial dysfunction of the umbilical artery and hemodynamic deterioration as a result of metabolic acidosis. Prevention of endothelial damage and metabolic acidosis could be the main target for successful fetal cardiac surgery.

Animals↗