Biomedical subjects

T Oki

Publications and source records attributed to T Oki.

At least 91 records · Page 5Linked to original sources

PubMed1998

Regional left ventricular wall motion abnormalities in myocardial infarction and mitral annular descent velocities studied with pulsed tissue Doppler imaging.

We evaluated global left ventricular (LV) systolic function from mitral annular systolic motion velocities measured by pulsed tissue Doppler imaging in patients with previous myocardial infarction (MI) and LV regional wall motion abnormalities. The subject group consisted of 45 patients with wall asynergies, 3 with ischemic cardiomyopathy, 8 with dilated cardiomyopathy, and 15 healthy control subjects. The peak systolic descent velocity (Sw) and the time from the electrocardiographic Q wave to the peak of the systolic wave (Q-Sw) were measured at 6 mitral annular sites obtained from 2-dimensional apical long-axis, 4-chamber, and 2-chamber echocardiograms; these variables were compared with the LV ejection fraction (EF) calculated from the left ventriculogram. The mean Sw at the sites corresponding to the infarct regions was significantly lower and the mean Q-Sw was significantly longer in the MI groups than in the control group. The mean Sw and Q-Sw at all 6 sites in the ischemic and dilated cardiomyopathy groups were significantly lower and longer, respectively, than those of the control group. There were significant correlations between the EF and the means of the Sw and Q-Sw values at the sites corresponding to the infarct regions in the MI groups. In the ischemic and dilated cardiomyopathy groups, significant correlations existed between the EF and the means of the Sw and Q-Sw values at all 6 sites. Thus the parameters obtained from mitral annular systolic motion velocities with pulsed tissue Doppler imaging reflect LV asynergy corresponding to the infarct regions in patients with MI, and global LV systolic function may be evaluated with these parameters.

Cardiac Catheterization↗

PubMed1998

Assessment of left ventricular systolic wall motion velocity with pulsed tissue Doppler imaging: comparison with peak dP/dt of the left ventricular pressure curve.

To assess the usefulness of the tissue Doppler imaging variables for the evaluation of left ventricular (LV) systolic function, we compared variables obtained by the pulsed Doppler method with the LV ejection fraction (%EF) and the maximum value for the first derivative of LV pressure (peak dP/dt). We examined 65 patients, including 15 patients with noncardiac chest pain, 15 with ischemic heart disease, 15 with dilated cardiomyopathy, 10 with hypertensive heart disease, and 10 with asymmetric septal hypertrophic cardiomyopathy. The subendocardial systolic wall motion velocity patterns were recorded for LV posterior wall and ventricular septum in the parasternal LV long-axis view. The peak dP/dt was significantly lower in the hypertensive heart disease, hypertrophic cardiomyopathy, and dilated cardiomyopathy groups. The peak systolic velocity was lower and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall was longer in the hypertensive heart disease (5.9 +/- 0.5 cm/sec and 215 +/- 21 msec, respectively), hypertrophic cardiomyopathy (6.2 +/- 0.9 cm/sec and 217 +/- 17 msec, respectively), and dilated cardiomyopathy (5.2 +/- 0.8 cm/sec and 235 +/- 26 msec, respectively) groups than in the noncardiac chest pain (7.7 +/- 0.9 cm/sec and 187 +/- 24 msec, respectively) and the ischemic heart disease (7.6 +/- 0.8 cm/sec and 184 +/- 22 msec, respectively) groups. In all groups, the peak systolic velocity and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall correlated directly and inversely, respectively, with the %EF (r = 0.59, p < 0.0001; r = -0.59, p < 0.0001) and the peak dP/dt (r = 0.75, p < 0.0001; r = -0.68, p < 0.0001). Both tissue Doppler variables for the ventricular septum did not correlate with the %EF but roughly correlated with peak dP/dt. We conclude that the systolic LV wall motion velocity parameters obtained by pulsed tissue Doppler imaging may be useful for noninvasive evaluation of global LV systolic function in patients with no regional asynergy.

Cardiac Catheterization↗

PubMed1998

Left ventricular diastolic properties of hypertensive patients measured by pulsed tissue Doppler imaging.

Examination of left ventricular (LV) diastolic dysfunction in hypertensive patients has been based on parameters obtained from the transmitral flow velocity during pulsed Doppler echocardiography. However, these parameters are affected by loading conditions. We evaluated LV diastolic function along the longitudinal and transverse axes by pulsed tissue Doppler imaging (TDI) in 50 hypertensive (HT) patients and 36 age-matched healthy volunteers (N). Transmitral flow velocity was recorded by pulsed Doppler echocardiography. LV posterior wall motion velocity along the longitudinal and transverse axes also was recorded by pulsed TDI. In both groups, peak early diastolic velocity of the LV posterior wall (Ew) along the transverse axis (N: 15.8+/-5.2 cm/s, HT: 12.2+/-4.4 cm/s) was higher than that along the longitudinal axis (N: 12.7+/-3.1 cm/s, HT: 9.5+/-3.3 cm/s). Peak atrial systolic velocity of the LV posterior wall (Aw) along the longitudinal axis (N: 9.1+/-1.8 cm/s, HT: 9.7 +/-2.6 cm/s) significantly exceeded that along the transverse axis (N: 8.0+/-2.2 cm/s, HT: 8.4+/-2.4 cm/s) in both groups. The Ews were lower and the Aws were higher along both axes in the patient group than in the control group. The time intervals from the aortic component of the second heart sound to the peak of the early diastolic wave (IIA-Ews) along both the transverse (N: 142+/-18 ms, HT: 154+/-19 ms) and longitudinal (N: 151 16 ms, HT: 162+/-20 ms) axes were longer in the patient group. In 29 patients, Ews along both axes correlated negatively (transverse: r = -0.80, P < .0001; longitudinal: r = -0.71, P < .0001) and IIA-Ews correlated positively (transverse: r = 0.81, P < .0001; longitudinal: r = 0.74, P < .001) with the time constant of the LV pressure decay during isovolumic diastole. The Aws along both axes in the 24 patients without pseudonormalization in transmitral flow velocity correlated positively (transverse: r = 0.60, P < .001; longitudinal: r = 0.74, P < .0001) with the LV end-diastolic pressure. In conclusion, LV relaxation and filling along the longitudinal and transverse axes were impaired in many patients with hypertension. Pulsed TDI was useful for evaluating LV diastolic dynamics in this disease.

Aged↗

PubMed1998

Spectroscopic studies on the interaction of pradimicin BMY-28864 with mannose derivatives.

Pradimicin BMY-28864 (Pm) is an antibiotic effective against yeasts and fungi, and is known to bind mannose in the presence of Ca2+. We examined spectroscopically the mode of interactions among Pm, Ca2+, and glycosides of mannose and mannose oligosaccharides (Manalpha1-OMe, Manalpha1-2Manalpha1-OMe, Manalpha1-3Manalpha1-OMe, Manalpha1-4Manalpha1-OMe, Manalpha1-6Manalpha1-OMe, Manalpha1-6(Manalpha1-3)Manalpha1-OMe, and Man9GlcNAc2-Asn, a high mannose type N-linked oligosaccharide). All the mannosides interacted with Pm in the presence of Ca2+ and caused absorbance changes. The absorbance changes occurred nonlinearly with respect to the carbohydrate concentration and do not follow a simple binding isotherm equation, suggesting a unique multistep interaction mode. The concentrations that induced half the maximum absorbance change were approximately 10 mM for the mono- and di-mannosides and around 1.5 mM for the trimannoside and Man9GlcNAc2-Asn. Methyl alpha-D-glucopyranoside, methyl alpha-D-galactopyranoside, lactose, and myo-inositol did not affect the absorbance of Pm up to 50 mM. Ca2+ alone also influenced the absorbance of Pm. The absorbance between 200 and 700 nm decreased hypochromically when Ca2+ was added. The concentration that gave half the maximum absorbance decrease caused by Ca2+was around 15 microM. Our results suggest that two Pm molecules bind one C a2+, and each Pm binds two mannosyl residues.

Anthracyclines↗

PubMed1998

A woman with three ectopic pregnancies after in-vitro fertilization and embryo transfer.

Although a higher incidence of ectopic pregnancy has been reported after in-vitro fertilization (IVF) and embryo transfer, three ectopic pregnancies in the same woman is very rare. A patient of 32 years underwent IVF-embryo transfer six times within 3 years. Three of four conceptions resulted in ectopic pregnancies. The first involved simultaneous intrauterine and left tubal pregnancy, the second was a right tubal pregnancy, and the third was a right interstitial pregnancy. In IVF-embryo transfer, bilateral salpingectomy does not remove the risk of interstitial or cornual pregnancy.

Adult↗

PubMed1998

Coronary flow velocity patterns immediately after reperfusion reflect the pathologic characteristics of reperfused myocardium in canine models of acute myocardial infarction.

BACKGROUND: It is difficult to evaluate the extent of myocardial injury after successful reperfusion following acute myocardial infarction (AMI). We investigated the relationship between the coronary flow velocity pattern immediately after reperfusion and pathologic characteristics after myocardial reperfusion injury in dogs. METHODS: We measured distal coronary flow velocity variables in the left circumflex coronary artery in a canine model of AMI (n = 12) 10 min after the release of a clamp (3-10 h clamp procedure) using a 0.35 mm Doppler guide-wire. Dogs were divided into two groups according to presence or absence of early systolic retrograde coronary flow. Hearts were excised 2 h after reperfusion and examined histopathologically. RESULTS: The clamping time tended to be longer in dogs with early systolic retrograde coronary flow. Neutrophil infiltration was observed in the myocardium of dogs without systolic retrograde flow (n = 9); hemorrhage was rarely detectable and the myocardium maintained a bundle form. However, the bundle form of the myocardium became rough, and the severity of the incidence of hemorrhage tended to increase as the ratio of the diastolic coronary flow velocity to systolic velocity (DSVR) decreased. Vacuolar degeneration of the myocardium was also observed in hearts with a relatively low DSVR. In the group with systolic retrograde flow (n = 3), hearts were characterized by coagulation necrosis, marked vacuolar degeneration of the myocardium and diffusely distributed red cells in the intermyocytes. Systolic antegrade flow velocity was much reduced in this group, resulting in a markedly increased DSVR. These findings appeared to be related to severe myocardial damage. CONCLUSIONS: Coronary flow velocity patterns immediately after successful reperfusion appear to reflect the pathologic characteristics of the reperfused myocardium in dogs with AMI.

Animals↗

PubMed1998

Menstrual disorders in patients undergoing chronic hemodialysis.

OBJECTIVE: To investigate the etiology of menstrual disorders in patients undergoing chronic hemodialysis (CHD). METHODS: The menstrual histories, along with hormonal, biochemical, and hematological data, were investigated in 25 reproductive-aged CHD patients. RESULTS: All subjects had had regular menstrual cycles before entering CHD therapy. Of the 20 women who developed amenorrhea after beginning CHD therapy, 8 showed a return to their regular cycles and 6 improved to oligomenorrhea, 3 months to 66 months later, while 6 remained amenorrheic. The serum prolactin (PRL) levels were significantly higher in the patients (n = 9) with normogonadotropic amenorrhea or oligomenorrhea than in patients (n = 13) with regular cycles (53.6 +/- 36.2 vs 27.8 + 15.2 ng/ml, p < 0.05). The serum LH levels were high in both groups. In a cross-sectional study, the serum PRL levels gradually decreased with longer duration of dialysis. CONCLUSIONS: Patients undergoing CHD are likely to develop menstrual disorders. Hyperprolactinemia in part contributes to these menstrual disorders. However, menstrual disorders in CHD patients tend to improve during long-term follow-up, because of the gradual decrease in serum PRL levels during long-term CHD therapy.

Adult↗

PubMed1998

Differences in transmitral flow velocity pattern during increase in preload in patients with abnormal left ventricular relaxation.

Changes in transmitral flow (TMF) and pulmonary venous flow (PVF) velocities during increases in preload were compared in patients with a higher peak atrial systolic velocity than peak early diastolic velocity (A/E > 1) for the TMF velocity to determine differences in hemodynamic response. Fifteen patients with dilated hearts, 22 with hypertrophied hearts and 15 control patients were studied. TMF and PVF velocities were recorded by transesophageal pulsed Doppler echocardiography before and during application of lower body positive pressure. The value for peak early diastolic velocity increased, while the isovolumic relaxation time decreased with increases in preload in all groups. The value for peak atrial systolic velocity decreased in the dilated-heart group, but increased in the hypertrophied-heart and control groups. The peak second systolic and early diastolic PVF velocities increased in the dilated- and hypertrophied-heart groups, but did not change in the control group. The peak atrial systolic PVF velocity and the difference in duration of the atrial systolic PVF and TMF velocities increased in the dilated- and hypertrophied-heart groups, and its changing rate was highest in the group with dilated hearts. These results suggest that both peak early diastolic and atrial systolic TMF velocities increase during increases in preload through the Frank-Starling mechanism in hypertrophied hearts. Furthermore, the left ventricular functional reserve was lower in the dilated-heart group. Thus, TMF and PVF velocities respond differently during increases in preload, depending on the underlying heart disease.

Blood Flow Velocity↗

PubMed1998

Relationship between left atrial function and plasma level of atrial natriuretic peptide in patients with heart disease.

To investigate the relationship between left atrial function and secretion of atrial natriuretic peptide (ANP), we analyzed left ventricular inflow and pulmonary venous flow, left atrial dynamics, intracardiac pressures, and plasma ANP level in 92 patients with various cardiac diseases. From the apical four-chamber view, maximal left atrial volume and percent fractional change of the left atrial area during atrial systole (LA-%AC) were calculated. The ratio of peak early filling velocity to peak atrial systolic velocity (E/A) in the left ventricular inflow and the ratio of peak systolic velocity to peak diastolic velocity (S/D) in the pulmonary venous flow were measured with the pulsed Doppler method. A significant linear correlation was found between plasma ANP levels and pulmonary capillary wedge pressure. Significant linear correlations were also found between left ventricular end-diastolic pressure and both maximal left atrial volume and LA-%AC. Plasma ANP level was significantly correlated with maximal left atrial volume, LA-%AC, E/A, and S/D. A multivariate analysis revealed that only LA-%AC was significantly correlated with the plasma ANP level. These results suggest that left atrial systolic dysfunction associated with a left atrial afterload mismatch is closely related to the ANP secretion.

Aged↗

PubMed1998

Echocardiographic assessment of right atrial function in patients with myocardial infarction with reference to obstructive lesions of the coronary arteries.

We assessed the relationship between right atrial (RA) function and obstructive lesions of the coronary arteries in 29 patients with recent or old myocardial infarction (MI). Patients were divided into 3 groups according to the location of obstructions as follows: obstruction at the proximal right coronary artery (segments 1 and 2) (RCA proximal group, n=9); obstruction at the distal RCA (segments 3 and 4) (RCA distal group, n=6); and obstruction at the left anterior descending coronary artery (LCA group, n=14). The RA volume and the fractional change in the RA area during atrial contraction (RA %AC) were evaluated by apical 2-dimensional echocardiography. The right ventricular (RV) end-diastolic pressure (RVEDP) was measured in 4 patients in the RCA proximal group and 4 patients in the LCA group. The ejection fraction of the right ventricle (RVEF) was measured by radionuclide angiography or 2-dimensional echocardiography in 7 patients in the RCA proximal group, 5 patients in the RCA distal group, and 7 patients in the LCA group. The RVEF tended to be lower in the RCA proximal group than in the RCA distal and LCA groups. The RA volume was significantly greater in the RCA proximal group than in the LCA group. The RA %AC was significantly smaller in the RCA proximal group than in the RCA distal and LCA groups. There were no significant differences in the early diastolic RV inflow velocity among groups, but the late diastolic RV inflow velocity was significantly lower in the RCA proximal group than in the RCA distal and LCA groups. There was no significant difference in the RVEDP between the RCA proximal and LCA groups. Thus, RA dysfunction in the RCA proximal group appeared to be due to myocardial damage rather than to afterload mismatch. These findings suggest that RA dysfunction may occur in patients with an inferior MI who have an obstructive lesion of the proximal RCA.

Aged↗

PubMed1998

Difference in systolic motion velocity of the left ventricular posterior wall in patients with asymmetric septal hypertrophy and prior anteroseptal myocardial infarction. Evaluation by pulsed tissue Doppler imaging.

The left ventricular (LV) posterior wall in patients with asymmetric septal hypertrophy or prior anteroseptal myocardial infarction (A-MI) frequently demonstrates normal or supernormal motion to compensate for hypokinesis of the interventricular septum. This study evaluated the systolic motion velocity of the posterior wall in these conditions using a pulsed tissue Doppler imaging system. The study population consisted of 30 patients with hypertrophic cardiomyopathy (HC) and asymmetric septal hypertrophy, 25 with prior A-MI and 30 normal controls. The systolic excursion of the posterior wall was obtained by M-mode echocardiography. The endocardial motion velocities of the posterior wall were obtained by pulsed tissue Doppler imaging. The systolic excursion of the posterior wall was significantly greater in the A-MI and HC groups than in the control group, and was significantly greater in the A-MI group than in the HC group. The peak systolic velocity of the posterior wall was significantly lower in the HC group than in the control and A-MI groups, and the time from the electrocardiographic Q wave to the peak of the systolic wave of the posterior wall was significantly longer in the HC group than in the other groups. There were rough negative and positive correlations between the LV end-diastolic pressure and the peak systolic velocity and time from the Q wave to the peak of the systolic wave, respectively. In conclusion, LV myocardial contractility in HC patients was impaired when compared to A-MI patients despite similar posterior wall motion on the M-mode echocardiogram. Pulsed tissue Doppler imaging method may provide new insights and allow further evaluation of myocardial dysfunction.

Cardiac Catheterization↗

PubMed1998

Right heart flow dynamics after tricuspid valve annuloplasty. Characteristics and time course.

To evaluate the effect of tricuspid annuloplasty (TAP) on right heart flow dynamics, we analyzed tricuspid inflow velocity pattern, jugular venous pulse and color Doppler flow signal of tricuspid regurgitation (TR) before and after surgery in 16 patients who underwent TAP (TAP group). Cardiac rhythm was atrial fibrillation in all patients. Twelve patients with lone atrial fibrillation served as controls (AF group). Patients in the TAP group were studied before and serially after surgery with a mean follow-up period of 2.7 years. TAP was performed according to the modified De Vega technique in all patients. In a comparison of the most recent data in the TAP group and the data in the AF group, the maximum tricuspid inflow velocity was significantly increased, and both the deceleration time of the tricuspid inflow velocity wave and the y-h interval of the jugular venous pulse were significantly prolonged in the TAP group compared to the AF group. Immediately after surgery, in the TAP group, the area of the TR jet was markedly decreased, and the deceleration time of the tricuspid inflow velocity wave was significantly prolonged compared to those before surgery. The area of the TR jet was dramatically decreased and remained small during the follow-up period. Thus, TAP may produce mild tricuspid stenosis but may also confer sustained preventive effects against TR.

Adult↗

PubMed1998

Relationship between flow dynamics in the left atrium and hemostatic abnormalities in patients with nonvalvular atrial fibrillation.

To investigate the relationship between left atrial (LA) flow dynamics and hemostatic markers in nonvalvular atrial fibrillation (AF), 45 patients with nonvalvular AF who had not received anticoagulants were evaluated by transesophageal echocardiography. We determined the LA appendage flow and the presence of LA spontaneous echo contrast (SEC) or thrombus. We measured plasma levels of thrombin-antithrombin III complex (TAT), fibrinopeptide A, D-dimer, beta-thromboglobulin, and platelet factor 4 in peripheral blood as hemostatic markers. The patients were divided into a low-velocity group (n = 19; sum of peak emptying and filling LA appendage flow velocities < 40 cm/s) and a high-velocity group (n = 26; > or = 40 cm/s). The maximum LA diameter was significantly greater and the LA expansion fraction was significantly smaller in the low-velocity group than in the high-velocity group. LA SEC or thrombus was observed in 11 patients (58%) in the low-velocity group, but not in any patients in the high-velocity group (p < 0.001). The plasma levels of TAT, fibrinopeptide A, D-dimer, beta-thromboglobulin, and platelet factor 4 were significantly higher in the low-velocity group than in the high-velocity group. The plasma levels of TAT, fibrinopeptide A, beta-thromboglobulin, and platelet factor 4 were significantly higher in 8 patients without LA SEC or thrombus in the low-velocity group than in 26 patients in the high-velocity group. Patients with nonvalvular AF accompanied by an enlarged and dysfunctioning LA and a decreased LA appendage flow velocity had increased intravascular coagulation-fibrinolysis activity and platelet activation. These abnormalities may be closely related to the thrombogenetic state in patients with nonvalvular AF.

Adult↗

PubMed1998

Signal transduction inhibitors, hibarimicins, A, B, C, D and G produced by Microbispora. I. Taxonomy, fermentation, isolation and physico-chemical and biological properties.

Strain TP-AO121 which produces a complex of novel tyrosine kinase inhibitors designated hibarimicins A, B, C, D and G was considered to be a new subspecies of Microbispora rosea, and the name, Microbispora rosea subsp. hibaria, was proposed. Hibarimicins A, B, C and D specifically inhibited the src tyrosine kinase activity without affecting protein kinase A or protein kinase C. They also showed in vitro anti-Gram-positive bacterial and antitumor activities. The molecular formulae of hibarimicins A, B, C, D and G were assigned to be C85H112O37, C85H112O37, C83H110O36, C85H112O38, and C85H112O39 respectively.

Actinomycetales↗

PubMed1998

Signal transduction inhibitors, hibarimicins A, B, C, D and G produced by Microbispora. II. Structural studies.

The structure of hibarimicins A, B, C, D and G which are inhibitors for tyrosine specific protein kinase are determined using spectroscopic techniques. Hibarimicins described in this report consist of a common aglycon and six deoxyhexoses. The aglycon contains a highly oxidized naphtylnaphthoquinone as a chromophore. Among them, hibarimicin B was identical with angelmicin B.

Actinomycetales↗

PubMed1998

Glucosylquestiomycin, a novel antibiotic from Microbispora sp. TP-A0184: fermentation, isolation, structure determination, synthesis and biological activities.

Glucosylquestiomycin, a novel N-glucopyranoside of questiomycin A, was isolated from the culture broth of Microbispora sp. TP-A0184. The absolute configuration of the sugar was determined as D-configuration by chemical synthesis. The new antibiotic showed antibacterial activity against gram-positive and -negative bacteria and yeasts and cytotoxic activity against U937 cells.

Anti-Bacterial Agents↗

PubMed1998

State of the art: "diastology" research 1998.

The performance of the left ventricle (LV) during diastole is defined by the pressure-volume relationship. Consequently, noninvasive techniques have been limited in the evaluation of diastolic function by their inability to evaluate intracardiac pressure, particularly LV filling pressure and end-diastolic pressure. Abnormalities of LV diastolic function play a major role in producing the clinical signs and symptoms of heart failure. Previous studies have demonstrated that the transmitral flow (TMF), pulmonary venous flow (PVF) and left atrial appendage flow (LAAF) velocity patterns determined by pulsed Doppler echocardiography are useful parameters for evaluating left atrial (LA) and LV hemodynamic events. However, these variables are influenced by loading conditions, particularly preload. Furthermore, it has become increasingly clear that abnormalities of LV diastolic function, such as relaxation and filling, can be assessed precisely using color Doppler M-mode echocardiography and pulsed tissue Doppler imaging irrespective of preload. This review presents a clinical approach to understanding the hemodynamic abnormalities of the LA and LV in a variety of cardiac diseases using these new modalities. In addition, the limitations of these techniques are discussed.

Atrial Fibrillation↗

PubMed1998

Electrophysiologic effects of quinaprilat in dogs during acute myocardial ischemia and following reperfusion.

BACKGROUND: There have been few studies concerning the electrophysiologic changes associated with the use of angiotensin-converting enzyme inhibitors in patients with acute myocardial infarction. We examined the electrophysiologic effects of quinaprilat in dogs during acute myocardial ischemia and following reperfusion. METHODS: The left anterior descending coronary artery was occluded for 10 min and reperfused for 10 min. Animals received intravenous quinaprilat (3 micrograms/kg per min, quinaprilat group) or saline (control group). We measured the ventricular effective refractory period and intra-myocardial conduction time within the left anterior descending coronary artery region (ischemic region) during myocardial ischemia and following reperfusion, and determined the frequency of ventricular fibrillation. RESULTS: The effective refractory period in the ischemic region decreased during myocardial ischemia and decreased further immediately after reperfusion in the control group. The intra-myocardial conduction time in the ischemic region increased during myocardial ischemia but rapidly shortened after reperfusion in the control group. In the quinaprilat group, however, no significant differences were evident between the ischemic and non-ischemic regions in either the effective refractory period or the intra-myocardial conduction time during myocardial ischemia or following reperfusion. The percentage shortening of the effective refractory period and the percentage prolongation of the intra-myocardial conduction time in the ischemic region were significantly lower in the quinaprilat group than in the control group during myocardial ischemia and following reperfusion. The frequency of ventricular fibrillation during myocardial ischemia and following reperfusion was significantly lower in the quinaprilat group (21%) than in the control group (74%; P < 0.01). CONCLUSIONS: Quinaprilat protects against electrophysiologic abnormalities, and may decrease arrhythmias during acute myocardial ischemia and following reperfusion.

Acute Disease↗