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Biomedical subjects

S Matsuda

Publications and source records attributed to S Matsuda.

At least 217 records · Page 12Linked to original sources

A case of variant angina pectoris with similar findings on both rest and matched exercise thallium-201 studies.

A patient with variant angina showed similar findings on both the rest and matched exercise 201Thallium (201Tl) myocardial perfusion scintigrams. The 65-year old man was admitted to hospital because of rest angina. His electrocardiogram during the attack disclosed ST segment elevation on inferior leads. However, emergency coronary arteriogram showed no fixed stenosis. Intracoronary injection of acetylcholine induced a spasm on the distal right coronary artery, but not in the left coronary artery. In the rest 201Tl study, septal perfusion was low on the early image, although partial redistribution of this site was observed on the delayed image without the appearance of chest pain or electrocardiographic ischemic change. Similary, in the 201Tl exercise study undergone 2 weeks later, septal redistribution was diagnosed because the early image had decreased septal perfusion. Both the exercise 123I-metaiodobenzylguanidine study and the rest 123I-betamethyl-p-iodophenyl-pentadecanoic acid study showed inferior abnormalities on the early and delayed images. Although a coronary spasm was not induced in the left anterior descending artery with the acetylcholine test, septal redistribution was observed on the delayed image of both the rest and exercise 201Tl studies. The mechanism of the redistribution on the rest 201Tl study was unclear.

Aged↗

[The French health care system and its reform].

The French health care system is characterized by its social insurance scheme with universal coverage, freedom of prescription and of location by the doctor, fee-for-service payment by patients, and free choice of doctor by patients, which essentially tends to inflate its health expenditures. Thus, the health expenditures of France has been increasing over the average expenditures of other European countries. Under the principle of autonomy of the social insurance fund, the increase in medical expenditures has been absorbed by a decrease in the reimbursement rate and an increase in the contribution rate of the insured. However, it is no longer possible to cope with this financial crisis by these traditional measures because of the worsening of the unemployment problem. Nowadays, the increase in the contribution rate is regarded as one of the important reasons for the economic stagnation of the French society. In order to cope with this difficult situation, the French government has changed its health policy from the demand side strategy to the supply side strategy. The concrete plan of this policy was presented by Prime Minister Alain Juppé (the Juppé plan). The plan consists of; 1) unification of the medical insurance scheme, 2) establishment of a ceiling on medical expenditures, 3) regionalization of health policy, 4) disclosure of medical information, 5) introduction of medical references, 6) creation of a social protection scheme for the dependent elderly, 7) introduction of an object tax for the social security fund, etc. These subjects have been materializing step by step after many twists and turn. The most important principles of the plan are the transparency of the medical information and the responsibility of each actor within the health system. The French government has conducted a lot of international comparable studies of health systems. According to the results of a series of active and profound discussions, the French government has conducted various social experiments. It is very meaningful for the Japanese government to analyze this process of health reform occurring in France in order to discuss the health system reforms in Japan.

Delivery of Health Care↗

Molecular cloning and sequence analysis of two endoinulinase genes from Aspergillus niger.

Two genomic DNAs encoding endoinulinase from Aspergillus niger 12 were cloned and sequenced. Open reading frames (ORFs) of the endoinulinase genes, inuA and inuB, both consisted of 1,548 nucleotides encoding 516 amino acids. It was suggested that the coding regions were not interrupted by introns. The ORFs differed from each other by 23 nucleotide substitutions or by eight amino acid replacements, indicating that the inuA and inuB genes arose by gene duplication. Each mature enzyme of 493 amino acids was preceded by a hydrophobic signal peptide of 23 amino acids. The enzymes contained two Cys residues and five potential sites for N-linked glycosylation. Partial amino acid sequences of the secreted enzyme suggested that it originated from the inuB gene product. The deduced amino acid sequences of the mature A. niger enzymes showed 73% identity with that of the Penicillium purpurogenum endoinulinase.

Amino Acid Sequence↗

Noise levels and hearing ability of female workers in a textile factory in Vietnam.

Noise and hearing ability profiles were determined in a textile factory in Vietnam. Noise mapping done in the weaving section showed that the noise levels exceeded the Vietnamese standard of 90 dBA by as much as 9 dBA in some areas. Audiometric tests performed on 69 female workers from the weaving section revealed that workers with more than 10 years of noise exposure had the worst hearing threshold levels at 1,000 and 4,000 Hz. Similar findings were observed for workers greater than 35 years old. The 4,000 Hz notch, suggestive of exposure to intense noise, was noted in the audiograms of 26 subjects.

Adult↗

Suppression of cell growth by ectopic expression of N-cadherin.

We found that ectopic expression of N-cadherin in 3Y1 caused tight association of cells and, thereby, substantially suppressed cell growth. N-cadherin expression inhibited neither tyrosine phosphorylation of cellular proteins, GTP uptake onto Ras, nor activation of MAP kinase, suggesting that it does not directly interfere the Ras-MAP kinase pathway. However, co-expression of N-cadherin with dominant negative Ras, S17N Ras, showed synergestic growth inhibitory effect, suggesting that N-cadherin signaling antagonizes the Ras-MAP kinase signaling. In addition, we found that N-cadherin yielded cell-cycle arrest at G0/G1 phase. These results strongly suggest that N-cadherin cell adhesion machinery works as a negative controller of cell cycle in 3Y1 and this growth suppressive function of cadherin is distinct from the epithelial morphogenetic function.

Actins↗

[Lung laceration caused by penetrating chest wall injury in Hanshin & Awaji earthquake: a case report].

A 36-year-old man having a left lower lobe laceration caused by penetrating chest wall injury was operated on 5 hours after Hanshin & Awaji Earthquake. At thoracotomy, significant destruction of the left lower lobe was observed. Therefore, we gave up repairing a lung, and performed left lower lobectomy, with a satisfactory outcome. Our hospital is located on 30 km south of seismic center, but the function of our hospital was not completely paralyzed. In Awaji island, emergent treatments were done satisfactorily.

Adult↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1996). I. Susceptibility distribution].

The frequencies of isolation and susceptibilities to antimicrobial agents were investigated on 680 bacterial strains isolated from patients with urinary tract infections (UTIs) in 10 hospitals during the period of June 1996 to May 1997. Of the above bacterial isolates, Gram-positive bacteria accounted for 30.4% and a majority of them were Enterococcus faecalis. Gram-negative bacteria accounted for 69.6% and most of them were Escherichia coli. Susceptabilities of several isolated bacteria to antimicrobial agents were as followed; 1. Enterococcus faecalis Ampicillin (ABPC) showed the highest activity against E. faecalis isolated from patients with UTIs. Its MIC90 was 1 microgram/ml. Imipenem (IPM) and vancomycin (VCM) were also active with the MIC90S of 2 micrograms/ml. The others had low activities with the MIC90S of 16 micrograms/ml or above. 2. Staphylococcus aureus including MRSA Arbekacin (ABK) and VCM showed the highest activities against both S. aureus and MRSA isolated from patients with UTIs. The MIC90S of them were 1 or 2 micrograms/ml. The others except minocycline (MINO) had low activities with the MIC90S of 32 micrograms/ml or above. 3. Staphylococcus epidermidis ABK and VCM showed the strongest activities against S. epidermis isolated from patients with UTIs. The MICs for all strains were equal to or lower than 2 micrograms/ml. Cefazolin (CEZ), cefotiam (CTM) and cefozopran (CZOP) were also active with the MIC90S of 4 micrograms/ml. Compared with antimicrobial activities of cephems is 1995, the MIC90S of them had changed into a better state. They ranged from 4 micrograms/ml 16 micrograms/ml in 1996. 4. Streptococcus agalactiae All drugs except MINO were active against S. agalactiae. ABPC, CZOP, IPM, and clarithromycin (CAM) showed the highest activities. The MICs for all strains were equal to or lower than 0.125 micromilligrams. Tosufloxacin (TFLX) and VCM were also active with the MIC90S of 0.5 micromilligrams. 5. Citrobacter freundii Gentamicin (GM) showed the highest activity against C. freundii isolated from patients with UTIs. Its MIC90 was 0.5 micrograms/ml. IPM and amikacin (AMK) were also active with the MIC90S of 1 microgram/ml and 2 micrograms/ml, respectively. Cefpirome (CPR) and CZOP were also active with the MIC90S of 8 micrograms/ml. The MIC90S of the others were 16 micrograms/ml or above. 6. Enterobacter cloacae IPM showed the highest activity against E. cloacae. The MICs for all strains were equal to or lower than 0.5 microgram/ml. The MIC90S of ciprofloxacin (CPFX) and TFLX were 1 microgram/ml, the MIC90 of AMK was 2 micrograms/ml, the MIC90S of CZOP, GM and ofloxacin (OFLX) were 4 micrograms/ml. The MIC50S of cephems except CEZ, cefmetazole (CMZ) and cefaclor (CCL) had changed into a better state in 1996, compared with those in 1995. 7. Escherichia coli All drugs except penicillins and MINO were active against E. coli. Particularly CPR, CZOP and IPM showed the highest activities against E. coli. The MIC90S of them were 0.125 microgram/ml or below. Among E. coli strains, those with low susceptibilities to cephems except CEZ, cefoperazone (CPZ), latamoxef (LMOX) and CCL have increased in 1996, compared with those in 1995. 8. Klebsiella pneumoniae K. pneumoniae was susceptible to all drugs except penicillins, with the MIC90S of 2 micrograms/ml or below. CPR had the strongest activity, the MICs for all strains were equal to or lower than 0.25 microgram/ml. Flomoxef (FMOX), cefixime (CFIX), CZOP and carumonam (CRMN) were also active with the MIC90S of 0.125 microgram/ml or below. 9. Pseudomonas aeruginosa All drugs except quinolones were not so active against P. aeruginosa with the MIC90S were 32 micrograms/ml or above. Quinolones were more active in 1996 than 1995. The MIC90S of them were between 4 micrograms/ml and 8 micrograms/ml, and the MIC50S of them were between 1 microgram/ml and 2 micrograms/ml. 10. Serratia marcescens GM showed the highest activity against S. marcescens. Its MIC90 was 1 micro

Anti-Bacterial Agents↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1996). II. Background of patients].

Clinical background was investigated on patients with urinary tract infections (UTIs) from whom 752 bacterial strains were isolated in 10 hospitals during the period from June, 1996 through May, 1997. 1. Distribution of age and sex of patients and type of infections. Among males, those with ages 40 years or older were more frequent, the higher the ages of them. Among females, those with ages in the 60's were the most frequent (24.6%), and those with ages in the 20's, 40's and 50's were about 13%. With regard to type of infections, more than a half of infections among males with ages 30 years or older were of complicated types, but most of infections among females were of uncomplicated types, especially among females of ages less than 60 years. 2. Ages of patients and types of pathogens. The higher the ages of patients, the lesser became the isolation frequencies of Escherichia coli, but the higher were those of Pseudomonas aeruginosa and Klebsiella spp. 3. Effect of antibiotic use on isolation frequencies of pathogens. Use of antibiotics decreased pathogens isolated from patients with uncomplicated UTIs drastically (231 isolates before antibiotics compared to 60 after). Even isolated pathogens from patients with complicated UTIs decreased drastically with the use of antibiotics when indwelling catheters were not in use (193 isolates before antibiotics compared to 75 after), but when indwelling catheters were in use, antibiotics apparently failed to decrease the isolation frequency. 4. Surgical procedures and types of causative organisms for UTIs. From cases of uncomplicated UTIs, E. coli was the most frequently isolated, followed by Enterococcus Faecalis and Klebsiella spp. E. coli was the most frequently isolated organism from complicated UTIs without indwelling catheters. When a surgical procedures were not done, E. coli was isolated most frequently. From cases of complicated UTIs with indwelling catheters, P. aeruginosa, E. coli and E. faecalis were the organisms that were mainly isolated, with isolation frequencies of 23.2%, 15.2, 12.2, respectively. When no surgical procedures were used, isolation frequencies of P. aeruginosa, E. faecalis and Enterobacter spp. were 17.2%, 13.8%, 13.8%, respectively.

Adolescent↗

[Usefulness of thallium-201 myocardial scintigraphy during hyperventilation and accelerated exercise test in patients with vasospastic angina and nearly normal coronary artery].

The usefulness of thallium-201 (201Tl) myocardial scintigraphy was studied in 109 patients with vasospastic angina who had nearly normal coronary arteries (degree of stenosis < 50%). Coronary spasm was confirmed by pharmacologic agents in all 109 patients from January 1991 to June 1996. The appearance rate of visual redistribution on 201Tl myocardial scintigraphy was compared between four groups, 34 patients performing graded bicycle ergometer exercise starting at a work load of 50 W with increments of 25 W every 3 min [Ergo (3) group], 14 patients performing hyperventilation for 5 min [HV (5) group], 31 patients performing bicycle ergometer exercise with increments of 25 W every 1 min after 5 min hyperventilation [HV (5) + Ergo (1) group], and 30 patients at rest (Rest group). The value of the visual redistribution rate on 201Tl myocardial scintigrams in the HV(5) + Ergo (1) group (65%) was higher than that in the patients of other groups [Ergo (3) 41%, HV (5) 43%, Rest 33%]. However, there were no significant differences between the four groups. Stress 201Tl imaging after hyperventilation and accelerated exercise is useful to disclose ischemic evidence in about two thirds of patients with vasospastic angina and nearly normal coronary arteries, whereas about 40% of patients had visual redistribution on 201Tl myocardial scintigrams by performing standard procedures.

Acetylcholine↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1996), III. Secular changes in susceptibility].

Susceptibilities to various antimicrobial agents were examined for Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp., and Pseudomonas aeruginosa that were isolated from patients with urinary tract infections (UTIs) in 10 hospitals during June 1996 to May 1997, and the results were compared with those obtained during the same period in earlier years. 1. E. faecalis Among E. faecalis strains, those with high susceptibilities to ampicillin and minocycline appeared to have decreased in the latest study period. 2. S. aureus To almost antimicrobial agents, S. aureus isolated from uncomplicated UTIs showed low susceptibilities. But the MIC50s of those agents for S. aureus from complicated UTIs have changed better state. Particularly, the MIC50s of imipenem and clindamycin were 0.125 microgram/ml or below in the latest period for the first time in our history. 3. E. coli The susceptibilities to piperacillin and quinolones of E. coli isolated from uncomplicated UTIs were better than those isolated from complicated UTIs. 4. Klebsiella spp. The susceptibilities to almost antimicrobial agents of Klebsiella spp. have been better during the latest period, compared to those during period of 1995-1996, but to ofloxacin and ciprofloxacin have appeared to have been lower. 5. P. aeruginosa The susceptibilities to quinolones of P. aeruginosa have been better during the latest period compared those during periods of 1995-1996. But, the susceptibilities to cefozopran, carbapenems and monobactams of P. aeruginosa isolated from complicated UTIs appeared to have been lower. These susceptibility changes should be utilized in determining clinical treatments.

Anti-Bacterial Agents↗

Interlocking wedge osteotomy for cubitus varus deformity.

The authors reviewed 20 patients with cubitus varus deformity who were treated with the interlocking wedge osteotomy. All deformities including medial, posterior tilt and internal rotation of the distal fragment can be simultaneously corrected with this osteotomy. There were 14 males and 6 females whose average age was 5.0 years at injury and 14.1 years at surgery. The average follow-up period was 37 months. Thirteen patients had excellent results, 6 good, and 1 poor. The mean carrying angle was improved from 21.5 degrees of varus to 8.8 degrees of valgus, compared to 9.4 degrees of valgus on the uninjured side. The mean flexion of the elbow increased from 123.9 degrees to 134.3 degrees, and the mean hyperextension decreased from 12.0 degrees to 7.5 degrees. Three-dimensional correction and stable fixation can be achieved with this osteotomy.

Child↗

[Effects of institutional therapy and factors which influence the prognosis].

We examined the effect of institutional therapy on asthmatic children and evaluating the factors influencing the prognosis. We analyzed the questionnaires and laboratory findings obtained form the 565 children who had been treated with the therapy in National Higashi-Saitama Hospital from April 1978 to March 1997. The institutional therapy seems to be effective in the following 3 aspects. 1) Pulmonary function test such as FEV1.0, and bronchial hypersensitivity test such as acetylcholine inhalation test were improved. 2) Exercise abilities such as free running were improved. 3) More than 40% of the patients had no asthma attack or only a few mild asthma attacks requiring no medication. When compared the group whose symptoms were not improved with the remission group, who had no asthma attack, significant differences were seen in the following points, 1) The dose and the number of the medicines at the end of the hospitalization, 2) the bronchial hypersensitivity test, 3) the age of onset, 4) the age of the symptoms become perennial and 5) the term from the symptoms become perennial to the hospitalization were significantly different. The therapy principles including the recipes for exercise training were not different between the two groups. It is concluded that we should consider institutional therapy or, a combination of physical training and environmental control as one of the most important therepeutic methods when asthmatic symptoms become perennial in spite of the conventional medication.

Asthma↗

Induction of resting microglia in culture medium devoid of glycine and serine.

Cultured microglial cells usually exhibit ameboid morphology and peripheral macrophage-like properties, which are distinct from those observed in the normal mature brain. This might be caused by the inappropriate culture of microglial cells in high concentrations (approximately 200-400 microM) of Gly and Ser, although the concentrations of the amino acids in extracellular spaces of the brain parenchyma are quite low (approximately 5 microM). In the present study, we focused on the concentration-dependent effects of glycine (Gly) and serine (Ser) on microglial morphology and function. Under Gly/Ser-free and serum-free condition, the majority of rat microglial cells displayed round morphology, whereas in the presence of 5 microM Gly and 25 microM Ser, which correspond to the concentrations of Gly and Ser in the cerebrospinal fluid, they extended multiple branched processes and formed clusters of rough endoplasmic reticulum. On the other hand, Gly and Ser did not affect morphology of astrocytes. The viability of microglia was not affected by the changes in the concentrations of Gly and Ser. Metabolic activity, activities of acid phosphatase and inducible nitric oxide synthase, and superoxide anion (O2-) generation were all strongly suppressed in Gly/Ser-free medium or in medium containing physiological concentrations of both amino acids. Such activities were all enhanced in harmony with increases in the concentrations of Gly and Ser. Thus, microglial cells cultured in Gly/Ser-free medium, even though exhibiting ameboid morphology, appears to be in the functionally resting state. Furthermore, once the resting state was achieved, the microglial cells remained inactive even after the subsequent 24 h culture in serum-supplemented medium containing 400 microM of both amino acids. The medium conditioned by microglial cells that were cultured in the presence of 400 microM of Gly and Ser was toxic to cortical neurons, whereas the microglia-conditioned medium obtained in the absence of both amino acids facilitated the survival of cortical neurons. Therefore, microglial cells in the resting state, which was induced in the Gly/Ser-free condition, are likely to support neurons. Microglial cells could ramify on glass coverslips coated with astrocyte-derived extracellular matrix or on coverslips coated thinly with fibronectin and/or laminin even under the Gly/Ser-free condition. The ramified cells as induced in this way kept suppressed O2- generating activity. These findings suggest that resting ramified microglial cells with a neurotrophic activity can be induced with the combination of Gly/Ser-free medium and small amounts of extracellular matrix proteins, and that the resting state is rather stable.

Acid Phosphatase↗

Lack of active lung anaphylaxis in congenitally mast cell-deficient Ws/Ws rats sensitized with the nematode Nippostrongylus brasiliensis.

Ws/Ws rats are deficient in both mucosal- and connective tissue-type mast cells. To study the role of mast cells in active anaphylaxis, changes in vascular permeability in the trachea upon intravenous antigen challenge with Evans blue dye were examined in Ws/Ws, heterogenic Ws/+, and normal +/ + rats sensitized with the nematode Nippostrongylus brasiliensis. Antigen challenge resulted in fatal anaphylactic shock in some +/+ and Ws/+ rats, but not in Ws/Ws rats. Marked dye leakage developed within 30 min in the trachea of +/+ and Ws/+ rats, while Ws/Ws rats showed no substantial increases in the levels of vascular permeability. Ex vivo stimulation of sensitized lung fragments from +/+ animals with specific antigen induced significant releases of histamine and leukotriene (LT) C4, while sensitized Ws/Ws rat-lung fragments did not. In Ws/Ws rats, levels of nematode-specific IgE, IgG1 and IgG2a antibodies as well as levels of lung eosinophilia were not significantly different from those in +/+ rats. These results show that mast cell-deficient Ws/Ws rats fail to develop active anaphylaxis, and this is mediated probably by the lack of mast cell-derived mediators required for initiation of the reaction.

Anaphylaxis↗

[Polyclonal B-cell lymphocytosis with clinical and hematological features resembling hairy cell leukemia].

A 49-year-old man was admitted to our hospital for investigation of splenomegaly and lymphocytosis. He had no significant past history and was not a smoker. Physical examination revealed massive splenomegaly and no palpable superficial lymph nodes. Hematological examination showed a hemoglobin concentration of 10.5g/dl, a platelet count of 9.8 x 10(4)/microliter, and a leukocyte count of 21.2 x 10(3)/microliter with 70% abnormal lymphocytes. In May-Giemsa stained blood films, the abnormal lymphocytes had round nuclei, abundant, pale cytoplasm, and slightly serrated edges. Phase-contrast microscopic and scanning electron microscopic examinations revealed many long surface villi. Tartrate-resistant acid phosphatase activity in these cells was negative. The abnormal lymphocytes had a CD5-, CD10-, CD11a+, CD11c+, CD19+, CD20+, CD22+ phenotype. These features were similar to those described for a variant form of hairy cell leukemia (HCL-Japanese variant). However, studies of Ig gene rearrangement and expression of sIg revealed a polyclonal proliferation of B cells. On the basis of these findings, this case was diagnosed as hairy B-cell lymphoproliferative disorder, a recently described condition characterized by polyclonal B-cell lymphocytosis and features resembling HCL-Japanese variant. Serological assays for antibodies against Epstein-Barr virus suggested a past infection. Splenectomy alleviated the anemia and thrombocytopenia, but not the lymphocytosis.

Antigens, CD↗

[Clinical differences between variant and non-variant angina pectoris].

The differences in clinical characteristics were studied between variant angina pectoris with ST segment elevation during ischemic attacks and non-variant angina pectoris without ST segment elevation. Spasm provocation test was performed with either acetylcholine or ergonovine in 192 consecutive patients with vasospastic angina from January 1991 to June 1997. Thirteen patients were excluded because of insufficient data. Fifty-five patients had variant angina and 124 patients had non-variant angina. Coronary risk factors, serum cholesterol level, triglyceride level, high-density lipoprotein cholesterol level, history of syncope, the rates of second or third atrioventricular block and ventricular tachycardia or fibrillation, the incidence of organic stenosis (> or = 50%), the number of vessels with provoked spasm, the dose of acetylcholine and ergonovine used, and duration from the first appearance of chest pain were compared between the 2 groups. Patients with variant angina had more fixed stenosis (p < 0.01), required more percutaneous transluminal coronary angioplasty procedures, lower doses of intracoronary administration of acetylcholine for the induction of coronary arterial spasm and shorter duration from the first appearance of chest pains (p < 0.01) than patients with non-variant angina. However, there were no differences in other factors between the 2 groups. Variant angina pectoris has the same clinical characteristics as non-variant angina pectoris, although variant angina tends to cause higher spasmophilic activity and more fixed stenosis.

Acetylcholine↗

Geographic differences in seasonality of preterm births in Japan.

Based on vital statistics from 1979 to 1983, we used a time-series analysis using the Box-Jenkins model (ARIMA model) to compare the seasonality of preterm births among 47 prefectures in Japan. We also evaluated the relation between seasonality of preterm births and temperature. According to the Box-Jenkins analysis, a seasonal moving average was detected for 44 prefectures. The seasonality of preterm births in general shows a bimodal pattern with two peaks, one in summer and one in winter. The most interesting result is that the peaks show a trend with geographic location; one peak is dominant in winter among the northern prefectures and the other peak is dominant in summer among the southern prefectures. Another important result is that the winter increase in preterm births is negatively correlated with mean winter temperature (R = -0.424, p = 0.003); on the contrary, the summer increase in preterm births is positively correlated with the average summer temperature (R = 0.549, p < 0.001). These results suggest that climate-associated factors should be associated with the occurrence of preterm births in Japan.

Epidemiology↗

[Absence of induced spasm by intracoronary injection of 50 micrograms acetylcholine in the right coronary artery: usefulness of 80 micrograms of acetylcholine as a spasm provocation test].

This study investigated whether the maximal dose of 50 micrograms acetylcholine for the induction of coronary spasm in the right coronary artery is adequate. The acetylcholine test was performed in 388 consecutive patients to evaluate spasm from January 1994 to December 1997. Coronary spasm in the right coronary artery was induced in 43 patients, 37 men and 6 women with a mean age of 63 +/- 8 years by intracoronary injection of 80 micrograms of acetylcholine rather than 50 micrograms. These included 15 patients (35%) with rest angina, 23 patients with ischemic heart disease other than rest angina and 5 patients (12%) with non-ischemic heart disease. Acetylcholine was injected in incremental doses of 20, 50 and 80 micrograms into the right coronary artery. Positive spasm was defined as induction of more than 90% reversible narrowing associated with either usual chest pain or ischemic electrocardiographic changes. Clinical and angiographical characteristics was studied in these patients. Fifteen (35%) patients had rest angina and 4 patients had variant angina with ST elevation in the inferior leads. Two thirds of the patients had coronary spasm in the distal portion of the right coronary artery and one third of those disclosed spasm focally. Coronary spasm was induced in 38 (15%) of 246 patients with ischemic heart disease and in 5 (4%) of 142 patients with non-ischemic heart disease. The prevalence of positive spasm in patients with ischemic heart disease was significantly higher (p < 0.01) than in patients with non-ischemic heart disease. A dose of 80 micrograms of acetylcholine, more than the maximal standard dose, might be clinically useful for the induction of spasm in the right coronary artery if coronary spasm of this artery is strongly suspected.

Acetylcholine↗