Biomedical subjects

N Handa

Publications and source records attributed to N Handa.

At least 19 recordsLinked to original sources

PubMed2001

Initial effects of the left ventricular repair by plication may not last long in a rat ischemic cardiomyopathy model.

BACKGROUND: Long term effects of left ventricle (LV) repair surgery (LVR) for ischemic cardiomyopathy are not well understood. METHODS AND RESULTS: Sixty-nine rats developed ischemic cardiomyopathy with large akinetic LV area 4 weeks after the left anterior descending artery was ligated. In a second surgery 4 weeks later, 33 rats underwent LVR by plication of the akinetic LV area (LVR group), and 36 underwent rethoracotomy alone (sham group). No medication was used in either group. All rats survived the second surgery. LV end-diastolic dimension as measured by echocardiography, LV fractional shortening, and the maximal end-systolic pressure-volume relationship (E(max)) as calculated from the data by catheter-tipped manometer and echocardiography improved in the LVR group after the second surgery, but LV end-diastolic dimension and E(max) gradually deteriorated as time passed. LV end-diastolic pressure improved 1 week after LVR but rose significantly 4 weeks after LVR. Brain natriuretic peptide mRNA was lower in the LVR group than in the sham group 1 week after LVR but not 4 weeks postoperatively. CONCLUSIONS: Initial improvement in LV function and neurohormonal status after LVR did not last for 4 weeks in this rat model when untreated medically. The mechanism of deterioration should be elucidated to improve long-term results of LVR.

Animals↗

PubMed2001

Clinical and biologic characteristics for recurring neuroblastoma at mass screening cases in Japan.

BACKGROUND: It is said that most cases detected by neuroblastoma mass screening at 6 months of age tend to have a favorable clinical course after a surgical resection either with or without mild chemotherapy. However, a few cases have an unfavorable outcome. In the current study, the authors analyzed the clinical and biologic characteristics for recurring neuroblastoma in mass screening cases. METHODS: In 245 cases detected through mass screening in the Kyushu area in Japan, the clinical data and biologic features (N-myc status, DNA ploidy, Shimada histology, neuron-specific enolase (NSE), ferritin) were investigated, whereas, in particular, the data for recurring cases also were analyzed. RESULTS: Of 245 cases, 28 tumors had one or more biologically unfavorable prognostic factors, and 6 patients experienced recurrence. Three of the six patients with recurring disease underwent a complete resection of the primary tumor, whereas three cases had undergone an incomplete resection of the tumor. Regarding the initial chemotherapy, three cases received mild chemotherapy, two cases received no chemotherapy, and one case had high-dose multidrug chemotherapy. Regarding biologic prognostic factors, four of six cases with recurring disease had one or more unfavorable factors, whereas two cases had no unfavorable factors. Regarding the outcome after recurrence, four cases are CR, one case has a stable residual tumor, and one case died of disease with N-myc amplification. CONCLUSIONS: Most neuroblastomas detected by mass screening at 6 months of age have biologically favorable factors. However, approximately 10% of the cases had one or more unfavorable factors and thus might have a higher risk of recurrence than the patients with no unfavorable factors. Conversely, some cases with recurring disease had no unfavorable factors; however, the reason for this is still unclear. A long-term follow-up for mass screening cases is important, and it also might be necessary to research the established biologic factors and identify other new prognostic factors.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2001

Valvular heart operation in patients with previous mediastinal radiation therapy.

BACKGROUND: The outcome of valvular heart operations in patients with previous mediastinal radiation therapy was studied. METHODS: This is a single center retrospective study of 60 patients (37 females, 23 males) with a mean age of 62 +/- 15 years (28 to 88 years old) operated on from January 1976 to December 1998. Valvular heart operations performed included aortic valve replacements (n = 26), mitral valve procedures (n = 16), tricuspid valve procedures (n = 6), and multiple valve procedures (n = 12). A total of 264 clinical, hemodynamic, electrocardiographic and echocardiographic variables were analyzed. RESULTS: Total follow-up was 199 patient-years with a mean of 3.3 +/- 3.1 years and a range of 0 to 12.4 years old. Early mortality was 7 patients (12%). Early mortality in patients with constrictive pericarditis was 40% (4 of 10) compared with 6% (3 of 50) in patients without constrictive pericarditis. By univariate analysis, early mortality was associated with constrictive pericarditis (p = 0.011), reduced preoperative ejection fraction (p = 0.015), and longer cardiopulmonary bypass times (p = 0.037). A total of 14 patients (23%) required permanent pacemaker placement before (n = 7), during (n = 1), or early (n = 6) after valvular heart operations. There were 19 late deaths (malignancies, 7; heart failures, 5; other cardiac, 4; and other noncardiac, 3). Overall survival and freedom from late cardiac death and cardiac reoperation at 5 years for hospital survivors were 66% +/- 8%, 82% +/- 7%, and 93% +/- 4%, respectively. By univariate analysis, late cardiac death was associated with low ejection fraction (p = 0.002), New York Heart Association (NYHA) functional class IV (p = 0.004), preoperative congestive heart failure (p = 0.02), and preoperative atrial fibrillation (p = 0.038). Eighty-five percent of the discharged patients were in NYHA functional class I or II at follow-up. CONCLUSIONS: Early results of valve replacement after mediastinal radiation therapy were good except in the presence of constrictive pericarditis. Long-term outcome was limited by malignancy and heart failure. Early surgical intervention is recommended before the development of risk factors for late death, namely, severe symptoms, left ventricular dysfunction, and atrial fibrillation.

Adult↗

PubMed2001

Experimental genome evolution: large-scale genome rearrangements associated with resistance to replacement of a chromosomal restriction-modification gene complex.

Type II restriction enzymes are paired with modification enzymes that protect type II restriction sites from cleavage by methylating them. A plasmid carrying a type II restriction-modification gene complex is not easily replaced by an incompatible plasmid because loss of the former leads to cell death through chromosome cleavage. In the present work, we looked to see whether a chromosomally located restriction-modification gene complex could be replaced by a homologous stretch of DNA. We tried to replace the PaeR7I gene complex on the Escherichia coli chromosome by transducing a homologous stretch of PaeR7I-modified DNA. The replacement efficiency of the restriction-modification complex was lower than expected. Some of the resulting recombinant clones retained the recipient restriction-modification gene complex as well as the homologous DNA (donor allele), and slowly lost the donor allele in the absence of selection. Analysis of their genome-wide rearrangements by Southern hybridization, inverse polymerase chain reaction (iPCR) and sequence determination demonstrated the occurrence of unequal homologous recombination between copies of the transposon IS3. It was strongly suggested that multiple rounds of unequal IS3-IS3 recombination caused large-scale duplication and inversion of the chromosome, and that only one of the duplicated copies of the recipient PaeR7I was replaced.

Chromosomes, Bacterial↗

PubMed2001

Clinical usefulness of duplex ultrasonography for the assessment of renal arteriosclerosis in essential hypertensive patients.

The present study was carried out to investigate whether the renal resistive index (RRI), obtained by ultrasonic duplex scanning, is useful for the evaluation of renal arteriosclerosis in essential hypertensive patients. We also studied the relationships between RRI and other kinds of hypertensive target-organ damage, including carotid atherosclerosis. One hundred and two patients (56.4+/-9.4 years) with untreated mild or moderate essential hypertension were examined. The normal range of RRI was determined for 12 normal age-matched volunteers (55.0+/-6.6 years). Hypertensive organ damage was evaluated by funduscopy, electrocardiograms, and carotid B-mode imaging. Based on the mean and distribution of RRI in normal volunteers (0.60+/-0.05), the normal upper limit of RRI was found to be 0.7. RRI was correlated with creatinine clearance (CCr) (r=-0.61, p<0.05), and blood urea nitrogen (r=0.46, p<0.05), but not with serum creatinine. In addition, the incidence of abnormal RRI (>0.7) was higher in patients with left ventricular hypertrophy and in those with advanced carotid atherosclerosis (p<0.01, respectively). Thus, RRI appears to be more strongly associated with CCr than with serum creatinine, and it increases in patients with hypertensive end-organ damage. The assessment of RRI may be useful for the evaluation of early renal damage in essential hypertension.

Adult↗

PubMed2000

A novel, 11 nucleotide variant of chi, chi*: one of a class of sequences defining the Escherichia coli recombination hotspot chi.

In wild-type Escherichia coli, recognition of the recombination hotspot, chi (5'-GCTGGTGG-3'), by the RecBCD enzyme is central to homologous recombination. However, in the recC* class of RecBCD mutants, stimulation of recombination by the canonical chi sequence is not detectable, but the levels of homologous recombination are nearly wild-type. In vivo studies demonstrate that a member of this class of mutants, the recC1004 allele, encodes an enzyme that responds to a novel variant of chi, termed chi* (5'-GCTGGTGCTCG-3'). Here, we establish that, in vitro, the chi* sequence is recognized more efficiently by the RecBC(1004)D enzyme than is the wild-type chi. This is manifest by both a greater modification of nuclease activity and a higher stimulation of RecA protein-mediated joint molecule formation at chi* than at chi. Sequencing of the recC1004 gene revealed that it contains a frameshift mutation, which results in a replacement of nine of the wild-type amino acid residues by eight in the mutant protein, and defines a locus that is important for the specificity of chi-recognition. In addition, we show that this novel, 11 nucleotide chi* sequence also regulates the wild-type RecBCD enzyme, supporting the notion that variants of the canonical chi constitute a class of sequences that regulate the recombination function of RecBCD enzyme.

Alleles↗

PubMed2000

Heart transplantation for radiation-associated end-stage heart failure.

Radiation-induced heart disease is an increasingly recognized late sequela of mediastinal radiation therapy for malignant neoplasms. We report four cases of heart transplantation for end-stage heart failure induced by mediastinal radiation therapy. Short-term and intermediate-term results are excellent with all four patients currently surviving a mean of 48 months after transplantation. Neither a second malignancy nor recurrence of the primary malignancy has been observed to date. The early results of heart transplantation for end-stage, radiation-induced heart disease are encouraging.

Adult↗

PubMed2000

Characterization of the Neurospora crassa mus-25 mutant: the gene encodes a protein which is homologous to the Saccharomyces cerevisiae Rad54 protein.

Characterization of the Neurospora crassa mus-25 mutant suggests that it is defective in recombination repair and belongs to the uvs-6 epistasis group. It shows a high sensitivity to the alkylating agents methyl methanesulfonate (MMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), but not to UV radiation. It is barren (i.e. does not produce ascospores) in homozygous crosses. The frequency of MMS-induced mutations at the ad-3 loci is approximately three times higher than in the wild type. The ratio of homologous to nonhomologous integration of the pMTR::HYG plasmid is much lower than in wild type. The mus-25 mutant is epistatic to the mei-3 mutant for MMS sensitivity. mei-3, which is a homololog of the Saccharomyces cerevisiae gene RAD51, is a member of the uvs-6 epistasis group which contains several genes that are homologous to recombination repair genes in other organisms. The mus-25 gene was cloned by identifying a genomic DNA fragment which complements the MMS sensitivity of the mutant. The amino acid sequence deduced from the cloned DNA showed a high degree of homology to the Rad54 protein, which is involved in recombinational repair in S. cerevisiae. Comparison of the nucleotide sequences of the genomic and cDNAs of the mus-25 gene revealed an ORF of 2505 bp with a single 118-bp intron beginning immediately after the second nucleotide of the AUG start codon. The molecular weight of the deduced gene product was 93.5 kDa. The transcript level was raised within 60 min after UV irradiation or MMS treatment, as also observed for the expression of the other N. crassa recombinational repair genes, suggesting the existence of a common mechanism which induces expression of the recombinational repair genes in response to DNA damage.

Alkylating Agents↗

PubMed2000

The effect of trunk muscle exercises in patients over 40 years of age with chronic low back pain.

Previous studies of trunk muscle strength in patients with chronic low back pain (CLBP) have mainly reported on patients aged younger than 40 years. However, no such investigation has yet been done in middle-aged patients. Trunk muscle strength and the effect of trunk muscle exercises were investigated in patients with CLBP aged more than 40 years. Trunk muscle strengths were measured in a LBP group (52 patients) and a control group (60 volunteers) and the results for the two groups were compared. The LBP group was divided into three subgroups. Group A had only age-related spondylosis and group B had disk herniation and spondylolisthesis with age-related spondylotic change. Both these groups were able to continue exercises. Group C was made up of patients who had abandoned the exercise program. Trunk muscle strength and symptoms were assessed in each group. Both flexion and extension strength were decreased in the LBP group compared with the control group, with the reduction in extension strength being most marked. In both groups A and B, muscle strength increased and clinical symptoms improved. In contrast, no change was seen in group C. In older patients with CLBP, reduction of muscle strength was more marked in the spinal extensors than in the spinal flexors. It was confirmed that trunk muscle strengthening exercises are useful for increasing muscle strength and improving symptoms in such patients.

Adult↗

PubMed2000

Distraction in the lateral position in elbow arthroscopy.

To perform successful elbow arthroscopy, it is very important to have precise positioning and to distract the joint during arthroscopy. We have developed a method of distraction during elbow arthroscopy that enlarges the articular space while ensuring the stability of the elbow. Our method is simple and requires no expensive specialized instruments. Our distraction method using lateral positioning is useful and safe for elbow arthroscopy. Because the articular space is widened sufficiently, stability of the elbow is maintained and no complication was seen.

Arthroscopy↗

PubMed2000

Evolution of sequence recognition by restriction-modification enzymes: selective pressure for specificity decrease.

Several type II restriction-modification (RM) gene complexes kill host bacterial cells that have lost them, through attack on the chromosomal recognition sites of these cells. Two RM gene complexes recognizing the same sequence cannot simultaneously enjoy such stabilization through postsegregational host killing, because one will defend chromosomal sites from attack by the other. In the present work, we analyzed intrahost competition between two RM gene complexes when the recognition sequence of one was included in that of the other. When the EcoRII gene complex, recognizing 5'-CCWGG (W = A, T), is lost from the host, the SsoII gene complex, which recognizes 5'-CCNGG (N = A, T, G, C), will prevent host death by protecting CCWGG sites on the chromosome. However, when the SsoII (CCNGG) gene complex is lost, the EcoRII (CCWGG) gene complex will be unable to prevent host death through attack by SsoII on 5'-CCSGG (S = C, G) sites. These predictions were verified in our experiments, in which we analyzed plasmid maintenance, cell growth, cell shape, and chromosomal DNA. Our results demonstrate the presence of selective pressure for decrease in the specificity of recognition sequence of RM systems in the absence of invading DNA.

Cell Division↗

PubMed2000

Effect of E5510, a novel antiplatelet agent, on platelet deposition in atherothrombotic lesions: evaluation by 111In platelet scintigraphy.

We evaluated the short-term effects of a novel antiplatelet agent, 4-cyano-5,5-bis(methoxyphenyl)-4-pentenoic acid (E5510), using 111In platelet scintigraphy (PSG) and B-mode ultrasonography (US). Fifteen patients with platelet deposition at either the carotid bifurcation or abdominal aorta on PSG were randomized into two groups: seven were followed without anti-thrombotic medication (Group A) and eight received E5510 (4 mg x day(-1)) (Group B). After 8 weeks, PSG and US were repeated in all patients. Platelet deposition was assessed visually and semi-quantitatively using a platelet accumulation index. Visual analysis showed that seven out of eight patients became negative for platelet deposition after treatment in Group B, while none changed in Group A. The platelet accumulation index of vessels with platelet deposition was significantly reduced after treatment in Group B (12.4+/-3.9% vs 6.0+/-7.1%, p <0.01), while there was no significant change in the vessels without platelet deposition (2.9+/-3.0% vs 2.9+/-4.1%). In Group A, none of the vessels showed any change (8.1+/-6.4% vs 8.9+/-7.3%). However, there was no significant reduction of carotid plaque size in either group. Short-term E5510 therapy inhibited platelet deposition in active atherothrombotic lesions, and the combination of PSG and US was useful for evaluating the effectiveness of anti-thrombotic drugs in vivo.

Aged↗

PubMed2000

Cellular responses to postsegregational killing by restriction-modification genes.

Plasmids that carry one of several type II restriction modification gene complexes are known to show increased stability. The underlying mechanism was proposed to be the lethal attack by restriction enzyme at chromosomal recognition sites in cells that had lost the restriction modification gene complex. In order to examine bacterial responses to this postsegregational cell killing, we analyzed the cellular processes following loss of the EcoRI restriction modification gene complex carried by a temperature-sensitive plasmid in an Escherichia coli strain that is wild type with respect to DNA repair. A shift to the nonpermissive temperature blocked plasmid replication, reduced the increase in viable cell counts and resulted in loss of cell viability. Many cells formed long filaments, some of which were multinucleated and others anucleated. In a mutant defective in RecBCD exonuclease/recombinase, these cell death symptoms were more severe and cleaved chromosomes accumulated. Growth inhibition was also more severe in recA, ruvAB, ruvC, recG, and recN mutants. The cells induced the SOS response in a RecBC-dependent manner. These observations strongly suggest that bacterial cells die as a result of chromosome cleavage after loss of a restriction modification gene complex and that the bacterial RecBCD/RecA machinery helps the cells to survive, at least to some extent, by repairing the cleaved chromosomes. These and previous results have led us to hypothesize that the RecBCD/Chi/RecA system serves to destroy restricted "nonself" DNA and repair restricted "self" DNA.

Chromosomes, Bacterial↗

PubMed2000

Changing profile of abdominal wall defects in Japan: results of a national survey.

BACKGROUND/PURPOSE: The incidence of gastroschisis has increased over the past 3 decades in a number of countries. To elucidate the Japanese status of anterior abdominal wall defects, the Japanese Society of Pediatric Surgeons conducted a national survey in Japan. METHODS: Information was obtained by sending out a questionnaire to 192 University Hospitals, Children's hospitals, and general hospitals that each had more than 200 beds. The characteristics of the patients including the birth date, birth weight, gestations, rate of associated anomalies, rate of antenatal diagnosis and prognosis, maternal age, gravidity, history of smoking, and drug use were analyzed. RESULTS: The authors obtained answers from 149 institutions, including 1,785 cases of omphalocele and 970 cases of gastroschisis, which were treated between 1975 to 1997. There was a significant increase in the incidence of gastroschisis, from 0.131 in 1975 to 1980, 0.269 in 1981 to 1985, 0.337 in 1986 to 1990, 0.461 in 1991 to 1995 to 0.467 per 10,000 births in 1996 to 1997. The incidence of omphalocele was 0.322 in 1975 to 1980, 0.567 in 1981 to 1985, 0.657 in 1986 to 1990, 0.741 in 1991 to 1995 to 0.626 per 10,000 births in 1996 to 1997, respectively. In the omphalocele group, 43.1% of the mothers were between 25 to 29 years of age, whereas in the gastroschisis group 42.6% of the mothers were 20 to 24 years of age. In the gastroschisis group, the number of primipara mothers was larger than that of multipara mothers. In the omphalocele group, approximately 10% of the mothers smoked during each period, whereas in the gastroschisis group, the percentage of smoking mothers increased chronologically from 12.9% in 1981 to 1985, 18.7% in 1986 to 1990, 23.5% in 1991 to 1995 and 29.3% in 1996 to 1997. A history of drug use by the mother was approximately 10% for both the omphalocele and gastroschisis groups. In the omphalocele group, 55.9% had associated anomalies against 21.8% in the gastroschisis group. Approximately 10% in the omphalocele group and less than 3% in the gastroschisis group showed chromosomal abnormalities. From 1986, a significant number of cases detected antenatally has been observed. CONCLUSIONS: There have been substantial changes in the incidence of anterior abdominal wall defects, particularly regarding gastroschisis in Japan. The reasons for such changes are most likely multifactorial, further epidemiological monitoring is thus called for.

Abnormalities, Multiple↗

PubMed2000

Pitfalls and results of immediate angiography after off-pump coronary artery bypass grafting.

BACKGROUND: We sought to determine the feasibility of off-pump coronary artery bypass grafting (OPCAB) in a consecutive series and prospectively assess the value of immediate post-operative coronary angiography. METHODS: All patients referred for coronary artery bypass grafting, within a four-month period, were approached as candidates for OPCAB. All 50 OPCAB patients were studied by immediate post-operative coronary angiography. RESULTS: The OPCAB procedure was feasible in 67% of patients (50/75). Five of 55 patients (9.1%) were converted to on-pump procedures, three for hemodynamic instability, and two because of deeply intramyocardial vessels. The other 20 underwent on-pump revascularization for anatomical and physiological reasons. The average age of OPCAB patients was 68.1 +/- 9.6 years; 26% were female, 74% male. Two (4%) were redo operations. Mean number of grafts was 2.9 +/- 0.8, 51 internal thoracic artery grafts (ITA), 17 radial artery grafts (RA), and 76 saphenous vein grafts (SVG). Angiographic graft patency was 90.2% for ITA, 88.2% for RA, and 96.1% for SVG. Interpretation of catheterization results was confounded by significant native and arterial graft spasm. Six of seven occluded arterial grafts and one of three SVG were probe patent at immediate reoperation (all had adequate flow by intra-operative doppler at the initial operation). Only two graft occlusions were noted in the 18 patients who did not receive protamine. The patency rate was 95.6% (131/137) when the probe patent anastomoses were excluded. Seven patients (14%) returned to the OR as a result of the catheterization findings; five to revise occluded grafts, one to improve the lie of a kinked SVG, and one to graft an intramyocardial intermediate ramus when an adjacent high diagonal was grafted instead (two of seven on-pump). All graft problems were found in the absence of hemodynamic instability or electrocardiogram changes. In-hospital mortality was 2% (1). Complications in survivors were atrial fibrillation in 12 patients (24.5%), permanent pacemaker in one (2%), endotracheal bleeding in one (2%), and take-back for bleeding in one (2%). CONCLUSIONS: There were a significant number of unexpected arterial graft occlusions. The reversal of heparin and ITA spasm appeared to be contributory. All patients with occluded grafts had no signs of trouble. Interpretation of immediate post-operative catherization is difficult because of significant native vessel and graft spasm. It reliably determines patency but it's value is suspect for determination of long-term graft adequacy.

Adult↗

PubMed1999

Structural basis for recognition of the tra mRNA precursor by the Sex-lethal protein.

The Sex-lethal (Sxl) protein of Drosophila melanogaster regulates alternative splicing of the transformer (tra) messenger RNA precursor by binding to the tra polypyrimidine tract during the sex-determination process. The crystal structure has now been determined at 2.6 A resolution of the complex formed between two tandemly arranged RNA-binding domains of the Sxl protein and a 12-nucleotide, single-stranded RNA derived from the tra polypyrimidine tract. The two RNA-binding domains have their beta-sheet platforms facing each other to form a V-shaped cleft. The RNA is characteristically extended and bound in this cleft, where the UGUUUUUUU sequence is specifically recognized by the protein. This structure offers the first insight, to our knowledge, into how a protein binds specifically to a cognate RNA without any intramolecular base-pairing.

Amino Acid Sequence↗

PubMed1999

Immunohistochemical distribution of bombesin-positive pulmonary neuroendocrine cells in a congenital diaphragmatic hernia.

Morphometrical analyses of the immunohistochemical expression of bombesin, which is one of the peptides produced by pulmonary neuroendocrine (PNE) cells, were carried out on the bronchioles of human congenital diaphragmatic hernia (CDH) neonates, and the findings were then compared with those in a gestational and postnatal age-matched control group. As a result, no difference was found in the number of bombesin-positive cells between the lungs of the control group and the unaffected side lungs in the CDH group except for the ratio of the bombesin-positive cells per unit of the bronchiolar surface area (P < 0.05). However, compared with the lungs in the control group, the affected side of the lungs in the CDH group showed a significant increase in the expression of bombesin, namely, the ratio of the bombesin-positive cells per bronchiole (P < 0.05), the ratio of the bombesin-positive cells per unit perimeter of the bronchioles (P < 0.05), and the ratio of the bombesin-positive cells per unit of the bronchiolar surface area (P < 0.01). These results thus suggest that hyperplasia of the PNE-cell system in the lungs of the CDH cases, especially on the affected side, exists in human fetuses. We also further speculate that PNE cells may thus play a role in the problems associated with CDH during intrauterine life in human beings.

Biometry↗

PubMed1999

Outcome of valve repair and the Cox maze procedure for mitral regurgitation and associated atrial fibrillation.

OBJECTIVE: The objective was to determine whether the Cox maze procedure provides adjunctive benefit in patients with atrial fibrillation undergoing mitral valve repair. METHODS: We compared the outcome of 39 patients who had the Cox maze procedure plus mitral valve repair between January 1993 and December 1996 (maze group) with that of 58 patients with preoperative atrial fibrillation who had mitral valve repair during the same interval by the same surgeons (control group). Patients in the 2 cohorts were similar for age, gender, preoperative New York Heart Association class III or IV, and duration of preoperative atrial fibrillation. The control group had a higher incidence of previous heart surgery and coronary artery disease. RESULTS: No operative deaths occurred, and 1 patient in each group required pacemaker implantation after the operation. Duration of cardiopulmonary bypass (122 +/- 40 minutes vs 58 +/- 27 minutes, P <.0001) and hospitalization (12.6 +/- 6.4 vs 9.3 +/- 3.4 days, P <.0025) were prolonged in patients having the Cox maze procedure. Overall, 2-year survival was similar (92% +/- 5% for maze patients and 96% +/- 3% for controls). Freedom from atrial fibrillation in the maze group was 74% +/- 8% 2 years after the operation compared with 27% +/- 7% for the control group (P <.0001). Freedom from stroke or anticoagulant-associated bleeding in the maze group was 100% 2 years after the operation compared with 90% +/- 8% in the control group (P =.04). At most recent follow-up, 82% of maze patients were in normal sinus rhythm (53% in control group). CONCLUSION: The addition of the Cox maze procedure to mitral valve repair is safe and effective for selected patients, and elimination of atrial fibrillation decreased late complications.

Aged↗