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Tadashi Isomura

Publications and source records attributed to Tadashi Isomura.

15 recordsLinked to original sources

A new concept of ventricular restoration for nonischemic dilated cardiomyopathy.

OBJECTIVE: Left ventricular restoration is used to treat patients with chronic progressive heart failure caused by nonischemic dilated cardiomyopathy. This study addresses the use of site selection to determine either lateral wall or septal exclusion. METHODS: Evolution of intraoperative echocardiography to define the site of poorest contraction and use of multiple biopsies to show the nonhomogeneous nature of damage are reviewed. To address the heterogeneity of extent of fibrosis in nonischemic cardiomyopathy, target selection was used to determine the mode of left ventriculoplasty. Either the lateral wall was excluded by partial left ventriculectomy (PLV) or septal anterior ventricular exclusion (SAVE or Pacopexy) was employed if the septum was primarily diseased. Surgical results in 107 high-risk (43% NYHA (New York Heart Association) class III and 57% class IV) patients with idiopathic dilated cardiomyopathy over the past 9 years are reviewed. RESULTS: Overall hospital mortality was 7.1% in 84 elective operations and 60.9% in 23 emergency operations, and fell from 42.8% (6 of 14) to 15.0% (14 of 93), when site selection for the area of left ventricular excision or exclusion was determined by the intraoperative echocardiography test. The SAVE/Pacopexy procedure was performed in 36 patients with 62.2% 5-year survival rate. For the entire cohort of PLV and SAVE/Pacopexy population, overall ejection fraction increased from 20 to 31%, and NYHA class improved from 3.6 to 1.8. The 1-, 5-, and 7-year survival rates were 66.9, 46.0, and 36.2%, respectively. In patients having the operation before inotropic dependent, the survival rate was 78.1, 58.0, and 50.2%, respectively. CONCLUSIONS: Left ventriculoplasty is effective for patients with idiopathic dilated cardiomyopathy with heart failure by proper patient selection, appropriate timing of the operation, and choice of the surgical procedure (exclusion site selection).

Adolescent↗

Septal anterior ventricular exclusion operation (Pacopexy) for ischemic dilated cardiomyopathy: treat form not disease.

OBJECTIVE: Restoration of left ventricle size and shape is an effective surgical procedure in patients with dilated cardiomyopathy. This report defines early and intermediate results following the reshaping of the left ventricle from spherical to ellipsoid configuration in patients with ischemic cardiomyopathy, employing a technique for LV restoration (LVR) that uses form rather than disease as the endpoint for oblique patch placement. METHODS: Between 1998 and 2004, a cohort of 83 patients with dilated ischemic cardiomyopathy underwent an operation to reshape the left ventricle. In 54 patients the Dor procedure was done, and 29 underwent the septal anterior ventricular exclusion (SAVE) procedure to emphasize the elliptical shape, whereby patch placement followed an oblique trajectory between the LV apex and septum below the aortic valve. Ventricular form, rather than the disease scar marked the suture placement site endpoint to create an ellipse. The mean age was 58+/-27, but SAVE patients had larger end systolic volume index (135+/-38 vs 95+/-25). Overall preoperative NYHA functional class III was in 69% and IV in 31 patients, but more SAVE patients were in class IV (38% vs 28%). The procedures were elective in 72 and emergent in 11, with similar entry criteria for each procedure. RESULTS: In combination with LVR operation, mitral surgery was performed in 49/83 and tricuspid annuloplasty in 23/83 patients, but these procedures were more common after SAVE (59% vs 44% and 45% vs 19%, respectively), because of larger LV volumes in SAVE patients; 2.8+/-1.3 coronary artery bypass grafts were used. Perioperative use of IABP or LVAD was 15 and 1, respectively in 83 patients. Hospital death was in 1/11 or 9% after emergent operations and 3/72 or 4% in elective procedures, with no difference between groups. After discharge from the hospital, NYHA class improved to class I or II in 57 patients, class III/IV in 14 patients, with 10 late deaths. The 5-year survival rate after the elective operation was 80.3% in SAVE and with elective operation and 77.4% in the Dor procedure. CONCLUSION: The SAVE or Pacopexy technique is easy to reshape the dilated left ventricle from spherical to ellipsoid form after the LVR, and the resultant improved configuration may contribute to the overall results for patients with ischemic dilated cardiomyopathy.

Adult↗

Left ventricle volume affects the result of mitral valve surgery for idiopathic dilated cardiomyopathy to treat congestive heart failure.

BACKGROUND: Mitral valve surgery is a recommended treatment for congestive heart failure; however, its effect for idiopathic dilated cardiomyopathy (DCM) with an extremely enlarged left ventricle (LV) is not well documented. We examined our long-term results of mitral valve surgery for idiopathic dilated cardiomyopathy. METHODS: Fifty-five patients of idiopathic dilated cardiomyopathy have undergone mitral valve surgery to treat intractable congestive heart failure since 1998. Forty-two patients were male with an average age of 55. Preoperative New York Heart Association functional class was III in 25, IV in 30, and 19 were dependent on inotropic infusion. The mitral valve was repaired in 37 patients and replaced in 18. The tricuspid valve was repaired in 35 patients and replaced in 3. We divided 46 elective cases into two groups by LV end-systolic volume index. RESULTS: Postoperatively, an intraaortic balloon pump was required in 2 patients and a left ventricular assist device in 1; both were emergent cases. Hospital mortality was noted 4.3% in elective cases (2 of 46) and 14.5% in overall cases (8 of 55). One-year, 3-year, and 5-year survival rate of elective cases was 73.3%, 58.2%, and 51.7%, respectively. Left ventricle size has decreased and LV contractility has increased in a small LV group year by year, but those in a large LV volume group have not changed subsequently after surgery. There was a significant difference noted in the survival rate of the two groups divided by LV end-systolic volume index. CONCLUSIONS: Mitral valve surgery for idiopathic dilated cardiomyopathy to treat end-stage heart failure is relatively safe and effective in elective status. However, isolated mitral reconstruction without any other type of surgery may not suffice for an extremely enlarged LV.

Adolescent↗

Septal anterior ventricular exclusion procedure for idiopathic dilated cardiomyopathy.

BACKGROUND: Eight-year experience with the septal anterior ventricular exclusion procedure for congestive heart failure due to idiopathic dilated cardiomyopathy was evaluated. METHODS: In 36 patients (27 men and 9 women with a mean age of 60 years) with heart failure; New York Heart Association class III/IV (21/15); and mitral regurgitation 2+ or greater, the procedure was indicated when the diastolic dimension was 75 mm or greater, and the septum was akinetic. A long, narrow oval patch was sutured to form a downsized elliptical left ventricle by excluding the septum and anterior wall. Mitral reconstruction was combined for all patients (26 repairs with undersized ring and 10 replacements with bioprosthesis) and tricuspid repair was added for 16 patients (44%). RESULTS: Hospital mortality was 13.8% (5 of 36), with 6.5% (2 of 31) in elective and 60% (3 of 5) in emergency operations. Ejection fraction increased from 20.9% +/- 6.4% to 27.5% +/- 8.8%, left ventricular diastolic dimension decreased from 81.9 +/- 9.2 mm to 70.1 +/- 10.0 mm, and left ventricular endodiastolic and endosystolic volume indices decreased from 236.5 +/- 65.0 mL/m2 to 183 +/- 60.5 mL/m2 and from 181.3 +/- 55.4 mL/m2 to 133.5 +/- 54.1 mL/m2, respectively. Left ventricular endodiastolic pressure decreased from 24.3 +/- 9.7 mm Hg to 19.4 +/- 7.6 mm Hg. Brain natriuretic peptide decreased from 975 +/- 866 pg/mL to 404 +/- 366 pg/mL at 1 to 6 postoperative months. Eleven late deaths were noted and were due to heart failure (6), sudden death (4) and stroke (1). The mean New York Heart Association class was 1.7 among the survivors. One- and 3-year survival rates were 67.5% and 60.7%, respectively. CONCLUSIONS: The septal anterior ventricular exclusion procedure with mitral reconstruction is a useful option for the treatment of advanced idiopathic dilated cardiomyopathy in extremely dilated left ventricle with akinetic septum.

Aged↗

Evidence of viral infection in the myocardium of American and Japanese patients with idiopathic dilated cardiomyopathy.

Enteroviruses have been implicated in the pathogenesis of idiopathic dilated cardiomyopathy (IDC). Recently, the association of adenovirus or parvovirus with IDC has been reported. Viral infection in the myocardium of American and Japanese patients with end-stage IDC was evaluated. Myocardial specimens from 30 American patients with IDC and 47 Japanese patients with IDC were analyzed for the presence of cardiotropic viruses. The strand-specific detection of enteroviral ribonucleic acid (RNA) was performed to determine viral activity in hearts with IDC. Established reverse transcription-polymerase chain reaction (PCR) or PCR techniques were used to detect genomic sequences of influenza viruses, mumps virus, adenovirus, parvovirus, herpes simplex viruses, varicella-zoster virus, and Epstein-Barr virus. Enteroviral RNA was detected in 7 of the 30 American patients (23%) and in 15 of the 47 Japanese patients (32%). Minus-strand enteroviral RNA, an indicator of active enteroviral RNA replication, was demonstrated in 5 of 7 plus-strand-positive American patients (71%) and in 12 of 15 plus-strand-positive Japanese patients (80%). Sequence analysis revealed that the viruses detected were Coxsackie B viruses. No genomic sequences of other viruses were detected in the myocardium of either American or Japanese patients with IDC. Therefore, active group B Coxsackie virus RNA replication in the myocardium was demonstrated in a significant proportion of American and Japanese patients with end-stage IDC. There was no evidence of persistent infection by other viruses in hearts with IDC. Specific therapy should be designed for Coxsackie virus positive patients with IDC.

Adult↗

Role of site selection for left ventriculoplasty to treat idiopathic dilated cardiomyopathy.

Ventriculoplasty was introduced to treat patients with chronic progressive heart failure from end-stage non ischemic dilated cardiomyopathy, which was presumed to be a homogeneous disease. However ventriculoplasty is not commonly used today, because variable results follow using only lateral ventriculoplasty as the treatment tool. This report traces our evolution in surgical management, defines that the homogeneous disease concept is not correct, and centers upon the importance of site selection, appropriate timing, and methods of patient selection. Left ventriculoplasty by either partial left ventriculoplasty (PLV) or septal anterior ventricular exclusion (SAVE or Pacopexy) was performed in 96 high risk (44% NYHA Class III, and 56% Class IV) patients with idiopathic dilated cardiomyopathy over the past 8 years. Overall hospital mortality was 8% in elective operations and 57% in emergency operations. Hemodynamic and functional improvement was evident from ejection fraction rising from 20% to 31%, and improved NYHA Class 3.6 to 1.8. The global series showed 1, 5 and 7 year survival rate was 66.4, 44.7 and 41.3%, respectively. However surgical results improved as experience allowed development of a strategy for timing, and defining proper exclusion site selection. Non homogeneous ventricular disease was identified, and 69% 4 year survival resulted from our intraoperative definition of the most diseased segment (septum or lateral wall), and then exclusion of this site. This evolving experience indicates that left ventriculoplasty is effective treatment for patients with end-stage cardiomyopathy, provided proper patient selection, appropriate timing of the operation, and choice of procedure are used as keys to a successful outcome.

Adolescent↗

Left ventricular restoration for ischemic cardiomyopathy--comparison of presence and absence of mitral valve procedure.

OBJECTIVE: Association of mitral regurgitation (MR) with ischemic cardiomyopathy (ICM) increases the degree of heart failure and its surgical management remains controversial. The aim of this study was to report the surgical results in patients with or without MR in association with ICM. PATIENTS AND METHODS: Ninety-two patients with ischemic cardiomyopathy (left ventricular [LV] ejection fraction less than 30% with global akinesis) underwent LV restoration. Pre-operative New York Heart Association (NYHA) functional class was either in class-3 or -4 in all patients. MR was moderate to severe in 38 patients (MR-group) and none or mild in 54 patients (noMR-group). Moderate to severe MR was repaired in addition to the complete coronary artery bypass (CABG) and LV restoration. All patients were followed up and echocardiogram was repeated every 6 months after the surgery. RESULTS: The procedure of LV restoration was selected pre- and intra-operative examination and endoventricular circular patch plasty was performed in 76, partial left ventricle resection in three, and septal anterior exclusion in 13. CABG was performed in 85 patients with mean 2.4+/-1.1 grafts in MR-group and 3.2+/-0.4 grafts in noMR-group (P<0.0001). In MR-group mitral valve plasty was performed in 24 and replacement in 14. Undersized (26 or 28 mm) circumferential mitral ring was used in 16 patients for mitral plasty. Emergent operation required in 15 patients (13 in MR-group and two in noMR group) and the hospital mortality was 18.4% in MR-group and 3.7% in no MR-group. Mitral regurgitation recurred in two patients with posterior ring annuloplasty and they underwent valve replacement. The post-operative NYHA functional class improved to class-1 or -2 in 65 patients and cumulative survival in 5 years including emergent and hospital deaths was 60.9% in MR-group and 70.1% in noMR-group. CONCLUSION: In association of MR to ICM, emergent operation required more often and perioperative mortality rate was high. However, the aggressive combined mitral operation in addition to CABG and LV restoration showed the improvement of clinical symptom and quality of life after the surgery.

Adult↗

Congenitally corrected transposition of the great arteries treated by partial systemic ventriculectomy.

Congenitally corrected transposition of the great arteries (CCTGA) is a rare congenital heart disease characterized by atrioventricular (AV) and ventriculo-arterial discordance;(1) that is, the left ventricle supports the pulmonary circulation and the right ventricle supports the systemic circulation. The most common cardiac anomalies in CCTGA include ventricular septal defect, pulmonary outflow tract obstruction and abnormalities of the systemic AV valve. (1) The dysfunction of the systemic ventricle occurs with increasing frequency in older patients with CCTGA, independent of their commonly associated structural defects.(2-4) We report a patient with CCTGA undergone the partial ventriculectomy for his systemic ventricular dysfunction.

Adult↗

[New surgical strategies for severe heart failure].

Alternative surgical procedures to heart transplantation for patients with severe congestive heart failure are developing in the past decade. Left ventricular restoration such as partial left ventriculectomy, endo-ventricular circular patch plasty, or septal anterior ventricular exclusion is effective for patients with operative indication and functional mitral regurgitation due to dilated heart can be repaired effectively in some patients. It is important to understand the surgical procedures and the indications for not only cardiac surgeons but also cardiologists, and combination of surgical and medical treatment can be an alternative to heart transplantation for properly selected patients.

Cardiac Surgical Procedures↗

[Dor's operation (endoventricular circular patch plasty)].

Endoventricular circular patch plasty (EVCPP; Dor's operation) for akinesis or dyskinesis in patients with ischemic heart disease may improve the cardiac function and prognosis. In this paper, the operative results are reviewed based on the reports in the literature and the author's experience. EVCPP was performed in patients with large dyskinesis and global akinesis. The akinetic left ventricular wall was excluded with an oval patch and the left ventricle was restored. In Dor's report, 49 patients with akinesis underwent EVCPP with a 10% mortality rate, and left ventricular function improved after surgery. The ejection fraction (EF) improved from 23% to 38% and end-diastolic volume index (EDVI) improved from 248 ml/m2 to 107 ml/m2. Recently, it was reported that the 8-year survival rate in 59 patients with akinesis was similar to that in 49 patients with large dyskinesis. In the author's experience there were 10 hospital deaths in 81 patients with akinesis, and 17 patients died in the late follow-up period, while 53 patients were in NYHA class I or II after surgery. The EF improved from 24% to 36% and the EDVI improved from 153 ml/m2 to 103 ml/m2. The EVCPP is effective in patients with ischemic cardiomyopathy to improve postoperative cardiac function and prognosis.

Cardiac Surgical Procedures↗

Partial left ventriculectomy--The Third International Registry Report 2002.

BACKGROUND: An international registry of partial left ventriculectomy (PLV) has been expanded, updated, and refined to include 440 cases voluntarily reported from 51 hospitals in 11 countries. RESULTS: Gender, age, ventricular dimension, etiology, ethnology, myocardial mass, operative variation or presence or absence of mitral regurgitation as well as transplant indication had no effects on event-free survival, which was defined as either absence of death or ventricular failure requiring ventricular assist device or listing for transplantation. Preoperative patient condition such as NYHA functional class IV, depressed contractility, and decompensation requiring an emergency procedure were associated with reduced event-free survival. Other risk factors included early date of surgery, lack of experience, and extended myocardial resection. Performance of PLV reached a peak by 1998 and was largely abandoned by 2000 except in Asia, where experienced institutes continue to perform PLV in patients in better condition with preserved myocardial contractility. CONCLUSION: Avoidance of delineated risk factors appears to improve recent survival and may help stratify high- or low-risk patients for PLV. An integrated approach with mechanical and biological circulatory assist may improve prognosis for patients with dilated failing hearts. While frequency of PLV has decreased, the concept of ventricular volume reduction has been extended to other volume reduction procedures and less invasive procedures now under clinical trial.

Adolescent↗

Quantitative analysis of cytokine mRNA expression in hearts from patients with nonischemic dilated cardiomyopathy (DCM).

PURPOSE AND METHODS: There is increasing evidence that inflammatory cytokines play an important role in the development of heart failure. To evaluate the role of cytokines in nonischemic DCM, we analyzed the relative quantity of cytokine mRNA expression in the hearts from DCM patients with refractory heart failure, using the ABI PRISM7700 real-time PCR system. We used heart tissues resected from 32 DCM patients at the time of elective partial ventriculectomy (PLV), and five biopsy specimens with normal histological findings as control. RESULTS AND DISCUSSION: Interleukin (IL)-1beta, IL-10, and Tumor Necrosis Factor (TNF)-alpha mRNA were expressed at low levels in all normal hearts. The number of IL-10-positive DCM cases was significantly smaller than normal controls (P = 0.0036). One (10%) of 10 DCM patients with IL-10 mRNA expression died after PLV, and 10 (45%) of 22 DCM patients without IL-10 mRNA expression died. IL-1beta mRNA was overexpressed (over twice the mean of control subjects) in 15 of 32, and TNF-alpha mRNA in 10 of 32 patients. We propose the classification of DCM patients into subgroups on the basis of cytokine mRNA expression. Anticytokine therapy or cytokine therapy may have potential in improving the condition of heart failure in certain subgroups of DCM patients. CONCLUSIONS: We suggest that DCM patients with heart failure deteriorate without IL-10 mRNA expression in the myocardium. The classification of DCM patients into subgroups on the basis of cytokine mRNA expression may have great value in considering the treatment of this heterogeneous disease state.

Adult↗

Left ventriculoplasty for nonischemic dilated cardiomyopathy.

From December 1996 to May 2001, we have performed 82 cases of left ventriculoplasty (LVP) for nonischemic dilated cardiomyopathy (DCM). Surgical procedure was partial left ventriculectomy in 70 patients and septal anterior ventricular exclusion in 12 patients with evaluation by utilizing intraoperative echocardiography. There were 70 men and 12 women with a mean age of 49, varying from 14 to 76. All patients had medically refractory heart failure with New York Heart Association (NYHA) Functional Class III in 33 patients and NYHA IV in 49; 34 patients were supported by inotropic infusion prior to the operation. Intra-aortic balloon pump (IABP) and left ventricle assist device (LVAD) were used in 12 and 2 patients at perioperative period, respectively. Hospital mortality was 8.2% in elective operation (5/61), 57.1% in emergency operation (12/21), and 20.7% overall. One- and four-year survival rates were 75.5% and 69.3% in elective cases, 37.9% and 0 in emergency cases, and 64.7% and 3.6% overall, respectively. Left ventricular (LV) ejection fraction increased from 22.3% to 29.0% at the time of surgery and has maintained around 33% up to two years. LV diastolic dimension and LV end diastolic pressure decreased from 83.8 mm to 65.0 mm; from 31.7 mmHg to 22.0 mmHg have maintained around 70 mm and 22.1 mmHg up to two years, respectively. Over one year most of the survivors were medically controlled within NYHA Class I-II. In conclusion, careful choice of surgical procedure by utilizing intraoperative echocardiography enables left ventriculoplasty to effectively treat severe heart failure with nonischemic cardiomyopathy.

Adolescent↗