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Biomedical subjects

S Koide

Publications and source records attributed to S Koide.

195 records · Page 11Linked to original sources
PubMedDate not supplied

Perfusion delay causes unintentional ischemic preconditioning in isolated heart preparation.

This study sought to show that unintentional preconditioning can be induced in the isolated perfused heart during the preparation procedure. The following four groups were compared: hearts were placed in ice cold saline and cooled for 15 s and then mounted to the Langendorff apparatus (n = 5; cool immediate group); hearts were cooled for 60 s and mounted (n = 5; cool delay group); hearts were mounted directly to the apparatus within 15 s after the isolation without cooling (n = 5; noncool immediate group); hearts were mounted without cooling, but the mounting was delayed for 60 s after the isolation (n = 5; noncool delay group). All hearts were paced at a fixed rate of 300 bpm, and an occlusion of left coronary (LCA) for 60 min was performed, which was followed by reperfusion for another 60 min. Coronary flow (CBF), left ventricular developed pressure (LVDP), and creatine phosphokinase (CPK) release did not change among the four groups during ischemia. At the end of reperfusion the LVDP values were 70 +/- 1%, 66 +/- 2%, 62 +/- 3%, and 73 +/- 2% of preischemic values in cool immediate, cool delay, noncool immediate, and noncool delay groups, respectively. CPK values were 116 +/- 4, 121 +/- 7, 138 +/- 6, and 29 +/- 1 x 10(3) U/g myocardium, and percentage necrosis/risk areas were 24 +/- 1.0%, 21 +/- 1.7%, 38 +/- 2.6%, and 13 +/- 0.5% in cool immediate, cool delay, noncool immediate, and noncool delay groups, respectively. The noncool delay group demonstrated high LVDP, least amount of CPK release, and smallest size of necrosis. These results indicate that an unintentional preconditioning effect can be induced when the cooling procedure is not applied and perfusion is delayed.

Analysis of Variance↗
PubMedDate not supplied

Specific cytotoxicity of antibody to YAL-198, a sperm antigen peptide, to murine zygote.

Active immunization with the peptide segments rSMP-230 and YAL-198, corresponding to the hydrophilic extracellular domain of two human sperm antigens (rSMP-B and YWK-II, respectively), reduced fertility in female rats by different mechanisms. The anti-rSMP-230 antibody interferes with human and murine fertilization, and the anti-YAL-198 antibody blocks the development of mouse embryos. The authors examined in vitro at which stage the antibodies to rSMP-230 and YAL-198 were cytotoxic to murine embryos up to morula/blastocyst stage. Anti-rSMP-230 antibody was not cytotoxic to any stages. On the other hand, the anti-YAL-198 antibody arrested the growth of embryos at the 2-cell stage but not at more advanced developmental stages. When the anti-YAL-198 antibody was used, spotty staining was observed only on the surfaces of embryos that had arrested at the 2-cell stage. Unstained embryos, however, continued to develop normally. In contrast, the anti-rSMP-230 antibody stained murine sperm but failed to stain murine ova and embryos. The present results suggest that the human sperm components rSMP-B and YWK-II play important roles in sperm-egg interaction and early development of the embryo, respectively.

Animals↗
PubMedDate not supplied

Partial left ventriculectomy in patients with dialated failing ventricle.

BACKGROUND: While partial left ventriculectomy (PLV) improves left ventricular energetic efficiency, concomitant reduction in mitral regurgitation may improve ventricular function. METHODS: Two hundred ninety-five patients undergoing lateral ventricular wall excision between the papillary muscles (lateral PLV) and 101 patients with an additional excision of papillary muscles and mitral valve replacement (extended PLV) were compared with 65 patients undergoing excision of anterior wall or ventricular aneurysm (anterior PLV). RESULTS: All patients had reduced functional capacity, New York Heart Association (NYHA) Class III to IV (3.62+/-0.49). Etiologies were cardiomyopathy (37.3%), coronary artery disease (32.3%), valvular disease (19.7%), Chagas' disease (7.8%), and others (2.8%). Patients undergoing lateral and extended PLV had cardiomyopathy as the primary cause of heart failure, while a majority of anterior PLV patients had ischemic disease. Associated procedures included mitral valvuloplasty or replacement (lateral PLV 67%, extended PLV 100%, anterior PLV 40%) and tricuspid annuloplasty (67%, 76%, 28%, respectively.) In each group after surgery, end-systolic dimension decreased more than end-diastolic dimension despite reduced mitral regurgitation. Although extended PLV resulted in greater volume reduction and less mitral regurgitation, these patients had delayed recovery and poor survival. Patients with valvular disease had the most advanced myocardial hypertrophy with the best survival, while those with Chagas' disease had more severe myocarditis, interstitial fibrosis, and the poorest survival. CONCLUSION: Lateral PLV improved hemodynamics and functional capacity as much as aneurysmectomy by reducing ventricular volume and mitral regurgitation. Inclusion and exclusion criteria have to be sought to make PLV safer and more effective.

Cardiac Surgical Procedures↗
PubMedDate not supplied

Partial left ventriculectomy: the 2nd International Registry Report 2000.

BACKGROUND: Partial left ventriculectomy (PLV) has been performed without standardized inclusion or exclusion criteria. METHODS: An international registry of PLV was expanded, updated, and refined to include 287 nonischemic cases voluntarily reported from 48 hospitals in 11 countries. RESULTS: Gender, age, ventricular dimension, etiology, ethnology, myocardial mass, operative variation, presence or absence of mitral regurgitation, and transplant indication had no effects on event-free survival, which was defined as absence of death or ventricular failure that required a ventricular assist device or listing for transplantation. Preoperative patient conditions, such as duration of symptoms (> 9 vs < 3 years; p = 0.001), New York Heart Association (NYHA) class (Class IV vs < Class IV; p = 0.002), depressed contractility (fractional shortening [FS] < 5% vs > 12%; p = 0.001), and refractory decompensation that required emergency procedure (p < 0.001) were associated with reduced event-free survival. Five or more cases in each hospital led to significantly better outcomes than the initial four cases. Rescue procedures for 14 patients nonsignificantly improved patient survival (2-year survival 52%) over event-free survival (2-year survival 48%; p = 0.49), with improved NYHA class among survivors (3.6 to 1.8; p < 0.001). Outcome was better in 1999 than in all series before 1999 (p = 0.02) most likely due to patient selection, which was refined to avoid known risk factors such as reduced proportion of patients in NYHA Class IV, FS < 5%, and hospitals with experience in 10 or less cases. A combination of these risk factors could have stratified 17 high-risk patients with 0% 1-year survival and 26 low-risk patients with 75% 2-year event-free survival. CONCLUSION: Avoidance of risk factors appears to improve survival and might help stratify high- or low-risk patients. Although less symptomatic patients with preserved contractility had better results after PLV, change of indication requires prospective randomized comparison with medical therapies or other approaches.

Adolescent↗
PubMedDate not supplied

Improved left ventricular contraction and energetics in a patient with Chagas' disease undergoing partial left ventriculectomy.

A 43-year-old patient with heart failure, precluded from heart transplantation or dynamic cardiomyoplasty because of Chagas' disease cardiomyopathy, mitral regurgitation, and ventricular mural thrombi, underwent mitral valvuloplasty and partial left ventriculectomy (PLV) between the papillary muscles. Intraoperative pressure-volume relationship analyses suggested improvement in left ventricular contraction, energetics, isovolumic relaxation, and mitral valve competency. These improvements allowed prompt, short-term recovery despite unchanged myocardial pathology, which suggests that a surgical approach can alter anatomic-geometric factors and achieve clinical improvement in a dilated failing ventricle.

Adult↗
PubMedDate not supplied

Histopathology of resected myocardium and outcome of partial left ventriculectomy.

BACKGROUND: Since preoperative hemodynamics are not proven to be a predictor of effects of partial left ventriculectomy (PLV), myocardial histopathology may be better correlated with effects and outcome of PLV. METHODS: Myocyte size (micron) in the excised myocardium was measured in 338 patients undergoing PLV. Endocardial fibrosis, interstitial fibrosis, and inflammatory cell infiltration were enumerated as none = 0, mild = 1, moderate = 2, and severe = 3. These histopathologic observations were correlated with patients' postoperative survival. RESULTS: Reduced survival was seen in patients with advanced (> or = moderate) interstitial fibrosis in all patients (n = 338, p = 0.064) and in the subgroup with nonischemic etiology (n = 229, p = 0.0039). Although correlation between endocardial and interstitial fibrosis was significant (r = 0.55, p < 0.01), endocardial fibrosis failed to correlate with postoperative survival. While Chagas' disease was associated with severe inflammation and poor survival, the presence of inflammatory cell infiltration had no effect on survival in all patients combined (p = 0.943). Although most patients (n = 266, 79%) had myocyte diameter over 30 micron, those with less hypertrophy (< 30 micron, n = 70, 21%) had a tendency toward increased survival (p = 0.067) regardless of underlying etiology. CONCLUSION: Interstitial fibrosis may be an important factor in stratification of patients for repair (PLV) or replacement (transplantation). PLV may be more beneficial in patients with less hypertrophy, before develqpment of interstitial fibrosis. Endomyocardial biopsy might not predict the extent or variation in degree of interstitial fibrosis, which may be better evaluated by other metabolic or perfusion studies that measure overall myocardial histopathology and viability.

Adolescent↗
PubMedDate not supplied

Mitral regurgitation after partial left ventriculectomy as the cause of ventricular redilatation.

BACKGROUND: It remains unclear whether ventricular redilatation after partial left ventriculectomy (PLV) is due to underlying pathology or to continued volume overload amenable to surgery. METHODS: Among patients undergoing PLV, 32 had Doppler echocardiography preoperatively, immediately after surgery (< 1 week), early after surgery (1-3 months), and late after surgery (8-14 months). Patients were divided into groups with mitral regurgitation (MR; MR+, n = 16) and without postoperative MR (MR-, n = 16) and were compared for ventricular size, performance, and survival. RESULTS: After initial surgical reduction, left ventricular dimension on average gradually increased back to the preoperative level in subgroups of patients with valvular disease and cardiomyopathy and in all patients combined. Most patients showed drastically reduced left ventricular dimension early after PLV. In MR+ patients, dimension increased back to the preoperative level within 3 months after surgery, whereas the MR- group maintained reduced dimension throughout the first year in all patients combined and in a subgroup of patients with cardiomyopathy. Occurrence of significant MR after PLV appeared to be related to severity of fibrosis in excised myocardium but not to severity of preexisting MR, etiology, or performance of mitral valvuloplasty. CONCLUSIONS: Early postoperative MR, residual or new, appeared to play an important role in dictating early hemodynamics and late outcome in patients undergoing PLV. Results suggest an aggressive simultaneous approach to abolish MR. Causative role of myocardial fibrosis remains unclear and needs further study.

Adult↗
PubMedDate not supplied

Perioperative ventricular arrhythmias in patients undergoing partial left ventriculectomy.

BACKGROUND: Although incidence of ventricular arrhythmias after partial left ventriculectomy (PLV) has been reported, there are no studies comparing incidence before and after PLV. Although operative scars may give rise to arrhythmias, improved energetic efficiency after PLV may decrease their incidence. METHODS: Pre- and postoperative ventricular arrhythmias were monitored by Holter ECG and analyzed in 17 patients undergoing PLV in Curitiba, Brazil. RESULTS: Although total 24-hour heart beat (THB) increased significantly (p = 0.018), ventricular premature contractions (VPCs) decreased markedly (p = 0.036), excluding one patient dying in low cardiac output (LOS) who had terminal arrhythmias increased multifold. In the remaining 16 patients, VPC pairs were also reduced significantly on the average (p = 0.038). In contrast, ventricular tachycardia (VT; more than three consecutive VPCs) disappeared in five patients, decreased in two patients, and newly occurred in four patients, with five patients showing no change; one of them developed a prolonged VT, successfully reversed by external cardioversion. CONCLUSIONS: Despite notable significant increase in THB immediately after PLV, PVC and PVC pairs were significantly decreased in contrast to VT, which disappeared in some patients and newly occurred in other patients, remaining constant on the average. Sustained VT occurring in a patient with all other arrhythmias suppressed may suggest a unique electrophysiological substrate, may justify prophylactic use of amiodarone or an implantable cardioverter-defibrillator, and may underscore the importance of further and extended studies.

Adolescent↗
PubMedDate not supplied

Transventricular mitral annuloplasty in a patient undergoing partial left ventriculectomy.

A 70-year-old male patient with heart failure resulting from dilated cardiomyopathy underwent a partial left ventriculectomy between the papillary muscles and a newly devised transventricular mitral annuloplasty. Intraoperative transesophageal Doppler echocardiography revealed reduced ventricular dimensions and corrected mitral insufficiency with unchanged ventricular filling patterns, allowing prompt recovery despite unchanged myocardial pathology.

Aged↗
PubMedDate not supplied

Partial left ventriculectomy for patients with ischemic cardiomyopathy.

BACKGROUND: Partial left ventriculectomy (PLV) has been performed in patients with dilated cardiomyopathy (DCM), but improved myocardial energetics may make PLV useful also for ischemic cardiomyopathy (ICM) unamenable to conventional treatment. METHODS: Of 262 patients undergoing PLV, 94 patients with ICM as the underlying pathology were analyzed and compared with 168 patients with DCM. RESULTS: ICM patients were older (57.3 years vs 50.9 years, p = 0.0001) and heavier (69.7 kg vs 65.9 kg, p = 0.039) than those with DCM, but ventricular end-diastolic and end-systolic dimensions were similar with comparably depressed fractional shortening (16% vs 15%, p = 0.294) and equally severe functional limitation [New York Heart Association (NYHA) Class 3.7 vs 3.6, p = 0.734]. A majority of patients in both groups underwent lateral PLV (76% vs 74%, p = 0.883) with myocardium excised between papillary muscles and simultaneous mitral valvuloplasty (41% vs 74%, p < 0.0001). Because ICM patients required coronary artery bypass grafting (CABG) more frequently (79% vs 0.6%, p < 0.0001), operation was more extensive in terms of bypass time (74 minutes vs 47 minutes, p < 0.0001), percentage requiring cardiac arrest (43% vs 19%, p < 0.0001), and arrest duration (34 minutes vs 28 minutes, p = 0.280), but all had similar resection and postoperative ventricular dimensions. Nonetheless, ICM patients required shorter intensive care unit (ICU) time (4.4 days vs 5.9 days, p = 0.048) and similar postoperative hospital stays, resulting in similar hospital survival rates (69% vs 71%, p = 0.778) and functional capacity in long-term follow-up. CONCLUSIONS: Results suggest that PLV can be performed in patients with ICM with comparable risks and benefits as in DCM. Relative efficacy of CABG and mitral repair as compared to volume reduction remains to be studied.

Adult↗