Database profile of the Fukuoka-City Information Platform for Community-based Integrated Care

BACKGROUND

The Fukuoka-City Information Platform for Community-based Integrated Care is an advanced big data platform that aggregates information on the health and medical services of Fukuoka citizens. Fukuoka City is engaged in a joint project with Kyushu University to promote policy making through a large-scale real-world data analysis. This paper describes the framework for this cooperative effort and the features of the analytical platform.

METHODS

Fukuoka City is the fifth most populous ordinance-designated city in Japan, with an estimated population of approximately 1.6 million. Under an agreement with Fukuoka City, Kyushu University was granted access to a portion of the city's anonymized healthcare database as secondary-use information. The database contains information on resident registration, health insurance claims, specific health checkups and health checkups for the older adults, specific health guidance, long-term care insurance data, and cancer screenings collected after fiscal year 2012. Each of these constituent datasets can be interlinked using anonymized hashed key variables, allowing individuals to be followed across databases and over time.

CONCLUSIONS

The platform allows longitudinal investigation of the complex association between various aspects of healthcare, such as medical procedures, examinations, interviews, medical costs, long-term care certifications, and care costs. The platform can provide valuable public-health information because it is relatively large for a single database, and because it allows analysis of data across multiple domains and tracing of individuals over time.

Association of gait speed with regional brain volumes and risk of dementia in older Japanese: The Hisayama study

BACKGROUND

To investigate the association of gait speed with regional brain volumes and the risk of incident dementia.

METHODS

A total of 1112 dementia-free Japanese residents aged ≥65 years who underwent brain magnetic resonance imaging were followed for 5.0 years (median). The participants were classified into the age- and sex-specific quartile levels of maximum gait speed. Regional gray matter volumes (GMV) and white matter hyperintensities volumes (WMHV) were measured by applying voxel-based morphometry methods. The cross-sectional association of maximum gait speed with regional GMV was examined using an analysis of covariance. We also estimated the association between maximum gait speed level and the risk of developing dementia using a Cox proportional hazards model. Mediation analyses were conducted to determine the contribution of regional brain volumes to the association between maximum gait speed and dementia.

RESULTS

Lower maximum gait speed was significantly associated with lower GMV of the total brain, frontal lobe, temporal lobe, cingulate gyrus, insula, hippocampus, amygdala, basal ganglia, thalamus, and cerebellum, and increased WMHV at baseline. During the follow-up, 108 participants developed dementia. The incidence rate of all dementias increased significantly with decreasing maximum gait speed after adjusting for potential confounders (P for trend = 0.03). The mediating effects of the GMV of the hippocampus, GMV of the insula, and WMHV were significant.

CONCLUSIONS

Lower maximum gait speed was significantly associated with an increased risk of dementia. Reduced GMV of the hippocampus or insula, and an increase in WMHV was likely to be involved in this association.

Deep peroneal nerve has a potential risk of injury during open-wedge high tibial osteotomy

PURPOSE

To assess the risk of injury to the neurovascular bundle on the interosseous membrane of the leg during drilling for distal screw insertion in open-wedge high tibial osteotomy (OWHTO), and to investigate the possible influence of the method of plate placement on the risk.

METHODS

This retrospective study involved, 55 patients (32 with a TomoFix plate, 23 with a TriS plate) who underwent postoperative CT scanning of the knee following OWHTO between 2009 and 2018. The angle and position of the locking plate, and the direction of screw insertion relative to the interosseous membrane were analysed.

RESULTS

All distal screws had a risk of neurovascular injury. In particular, 25 screws at the #4 hole (45%) had an extended insertion trajectory that intersected with the interosseous membrane. The angle of the proximal part of the TomoFix plate was a significant risk factor. In contrast, methods of TriS plate placement showed no statistically significant differences.

CONCLUSIONS

Extended insertion trajectories of distal screws were likely to intersect with the interosseous membrane with the neurovascular bundle potentially on its surface; thus, drilling for bicortical fixation posed a risk of neurovascular injury. The risk increased as the TomoFix plate was placed more medially, suggesting that bicortical drilling must be performed with the utmost attention when the plate is placed at the medial position. Given the particularly high risk at the #3 and #4 screw holes, monocortical fixation of a few distal screws is recommended as long as good stability is ensured.

Improvement of coronary vasomotion with eicosapentaenoic acid does not inhibit acetylcholine-induced coronary vasospasm in patients with variant angina

Impaired function of the endothelium may be a mechanism of the coronary vasospasm induced by acetylcholine. We examined whether purified eicosapentaenoic acid (EPA), a major component of fish oil, improves the coronary vasomotion in response to acetylcholine, and the effect of purified EPA on acetylcholine (ACh)-induced coronary vasospasm in 22 patients with variant angina. ACh was infused into the coronary artery both before and after 4 months of EPA treatment (EPA 1.8 g/day, n = 12). In the control group (n = 10) that did not receive EPA, the response of the coronary diameter to ACh did not change over time. In the EPA-treated group, the cholinergic response in non-spastic sites changed from vasoconstriction to vasodilation, while ACh-induced coronary vasospasm persisted at the spastic sites. Therefore, EPA treatment improved the coronary vasomotor responsiveness to ACh, but did not inhibit ACh-induced coronary vasospasm.

Prevalence and pathogenesis of silent myocardial ischemia following myocardial infarction

The objective of this study was to examine the prevalence and pathogenesis of silent myocardial ischemia during exercise following myocardial infarction. Exercise-induced myocardial ischemia was assessed by 201Tl-SPECT (single photon emission computed tomography) 4.5 weeks after acute myocardial infarction in 229 patients. Exercise-induced myocardial ischemia occurred in 109 patients (48%), and 72 (32%) had silent ischemia. Although the prevalence of multivessel coronary artery disease was similar between patients with silent and symptomatic ischemia, the size of reversible myocardial ischemia was larger in patients with symptomatic ischemia than in those with silent ischemia (21.3 +/- 3.0% vs 13.2 +/- 1.9% of LV, p < 0.05). The incidence of reversible ischemia remote from the infarct area was higher in patients with symptomatic ischemia than in those with silent ischemia (30% vs 17%, p < 0.10). The cause of silent ischemia after myocardial infarction may be closely related to the smaller size of reversible myocardial ischemia. Ischemia remote from, or adjacent to, the infarct area could be a factor in determining the presence or absence of pain.

Effects of continuous intravenous infusion of isosorbide dinitrate on development of tolerance to vasodilating action in human epicardial coronary arteries

This study was performed to determine the effects of long-term intravenous infusion on the coronary vasodilating actions of continuous intravenous and bolus intracoronary administration of isosorbide dinitrate (ISDN). With quantitative coronary angiography, the coronary diameter and the vasodilating response to intracoronary ISDN (1 mg) at angiographically normal segments were studied before and after intravenous administration of ISDN, 10 to 60 micrograms/min for 1 hour, 2 days, or 5 days. The vasodilating effects of intravenous ISDN were 72% +/- 13%, 65% +/- 21%, and 6% +/- 11% of the response to intracoronary ISDN in the baseline study in each group. Irrespective of the duration of intravenous infusion, subsequent intracoronary ISDN dilated coronary arteries to extent similar to that observed in each baseline study. In conclusion, significant coronary vasodilating effects of intravenous ISDN were observed after a 2-day infusion, whereas tolerance to the vasodilating effects apparently developed within 5 days of infusion. The vasodilating response to bolus intracoronary ISDN was preserved even when the vasodilating effects of intravenous ISDN were no longer present.

[Myocardial infarct size and left ventricular function in diabetic patients]

We determined the relationship between myocardial infarct size (MIS) estimated by electrocardiographic measurements of infarct size (QRS score) and left ventricular function estimated by angiographically left ventricular ejection fraction (EF). MIS estimated by QRS score were the same in both DM and NDM (5.2 +/- 0.5 vs 4.3 +/- 0.4: p greater than 0.05), but EF in DM was significantly lower than in NDM (43.1 +/- 1.4 vs 51. +/- 1.1%: p less than 0.05). There was clear linear correlation between MIS and EF in NDM (r = -0.71) but not in DM. EF was much lower in DM than in NDM even at the same QRS score level. There were no differences in blood pressure, serum lipid levels, age, and the site of the myocardial infarction. The most likely explanation for this appears to be due to a previous left ventricular disease in DM.

Preservation of endothelium-dependent vasodilation in the spastic segment of the human epicardial coronary artery by substance P

The objective of this study was to determine if endothelium-dependent vasodilation is preserved in the spastic segment of the epicardial coronary artery. Segmental responses of the coronary artery to substance P were examined by the use of a quantitative angiographic technique in 21 patients with variant angina. Coronary diameter at the basal state did not differ between the spastic and the nonspastic segments (2.3 +/- 0.2 mm, 2.3 +/- 0.4 mm, p greater than 0.05). Changes in coronary diameter in response to substance P did not differ between segments with ergonovine-induced spasm and nonspastic segments. Maximal dilation averaged 27.1 +/- 9.5% in the spastic segment and 24.4 +/- 9.6% in the nonspastic segment (expressed as a percent increase over the value before drug administration). It appears that both the potential of the endothelium to release endothelium-dependent relaxing factor and the dilating response of the smooth muscle to endothelium-dependent relaxing factor are preserved, even in the spastic segment.

[A mediating role of physiological arousal in social facilitation]

An experiment was conducted to examine the mediating role of physiological arousal in social facilitation. It was hypothesized that the elevation of arousal level by the presence of other persons or evaluative apprehension would facilitate task performance. Twenty-four male and 24 female college students performed simple task alone, with a cooperative person, or with a competitive person. One half of the subjects was given an instruction which would produce evaluative apprehension. Subjects' skin potential responses were measured as the indices of physiological arousal. Although the hypothesis was supported by the analysis of psycho-physiological index, but it was not at all by the self-reported index of arousal.

IgG-kappa type multiple myeloma in alcoholic cirrhosis--a case report

Transition from polyclonal to monoclonal gammopathy resulted in myeloma in the course of cirrhosis is rare but of interest. We treated such a case of multiple myeloma of IgG-kappa type associated with alcoholic cirrhosis. The case was a 72-year-old Japanese male patient who was admitted because of ascites and edema. Physical examination and laboratory findings including liver histology were compatible with alcoholic cirrhosis. Serum electrophoresis revealed monoclonal hypergammaglobulinemia of IgG-kappa. Bence Jones protein in urine was positive. Bone scintigraphy and roentgenography revealed small punched out lesions in the skull. A bone marrow clot section showed marked infiltration of atypical plasma cells. From these findings multiple myeloma associated with alcoholic cirrhosis was diagnosed. On the basis of a review of the reported cases, the possible relationship between monoclonal gammopathy and chronic liver diseases was discussed.

Early diastolic filling dynamics during experimental mitral regurgitation in the conscious dog

Diastolic flow into the left ventricle during mitral regurgitation must increase as total stroke volume increases in response to the volume overload. The mechanisms that allow augmented diastolic filling are not fully defined. Accordingly, the left ventricle of five dogs was instrumented with a micromanometer and sonomicrometers and studied during the conscious state before (control) and after the creation of significant mitral regurgitation. Serial measurements were made at control and up to 4 weeks after the creation of the volume overload. Heart rate, peak systolic wall stress, and peak positive dP/dt showed no significant changes between control and subsequent observations. End-diastolic volume and total stroke volume progressively and significantly increased during the 4-week course. When compared with the control state (51 +/- 4, mean +/- SD), the filling fraction during the first 40% of diastolic time was increased at 4 days (67 +/- 10%, p less than 0.001), 2 weeks (72 +/- 6%, p less than 0.001), and 4 weeks (76 +/- 10%, p less than 0.001). During the period of adaptation to the volume overload, filling fraction correlated with end-diastolic volume (r = 0.52, p less than 0.02) and total stroke volume (r = 0.80, p less than 0.001). Compared with the control state (0.81 +/- 0.04), eccentricity of the left ventricle at end systole decreased at 4 weeks (0.79 +/- 0.06, p less than 0.05); the absolute change in this ratio during the first 40% of diastolic time was significantly augmented at 2 weeks (0.09 +/- 0.02, p less than 0.05) and 4 weeks (0.11 +/- 0.04, p less than 0.005) compared with control (0.05 +/- 0.02). Ventricular elastance (pressure/volume) at end systole (minimum volume) was 1.70 +/- 0.50 mm Hg/ml at control, 1.09 +/- 0.46 at 4 days (p less than 0.05), 0.96 +/- 0.42 at 2 weeks (p less than 0.01), and 0.99 +/- 0.22 at 4 weeks (p less than 0.01). Moreover, the elastance change during the rapid-filling phase was significantly diminished after creation of mitral regurgitation. Thus, during the volume overload of mitral regurgitation, the left ventricle accommodates a higher percentage of its total stroke volume during early diastole; this adaptation can be correlated with augmented systolic shortening, and thereby with increased restorative forces or elastic recoil, and with reduced chamber elastance and eccentricity during the early part of diastole. Other potential mechanisms include altered systolic and relaxation loading, augmented elastic recoil of the left atrium, left atrium and left ventricular pressure gradient, accelerated myocardial inactivation, and increased adrenergic stimulation.

The usefulness of equilibrium radionuclide ventriculography in the diagnosis of arrhythmogenic right ventricular dysplasia and a report of cases of a familial occurrence

Arrhythmogenic right ventricular dysplasia (ARVD) is a recently identified clinical entity and its diagnosis rests on documentation of ventricular tachycardia (VT) of right ventricular origin and morphologic changes of the right ventricle. However, the diagnosis of ARVD is difficult noninvasively and often requires angiography. The usefulness of equilibrium radionuclide ventriculography as a noninvasive method for the diagnosis of ARVD has not been fully evaluated. We performed equilibrium radionuclide ventriculography in 7 patients with ARVD, 10 normal subjects and 9 patients with dilated cardiomyopathy (DCM). The right ventricular ejection fraction (EF) in patients with ARVD (25 +/- 8%, mean +/- SD) was lower (p less than 0.001) than that in normal subjects (56 +/- 7%) but was not significantly different from that in patients with DCM (32 +/- 10%). The left ventricular EF in patients with ARVD (57 +/- 12%) was lower (p less than 0.05) than that in normal subjects (70 +/- 7%), but higher (p less than 0.001) than that in patients with DCM (27 +/- 7%). These findings suggest that ARVD is a specific form of DCM which predominantly affects the right ventricle and that equilibrium radionuclide ventriculography may be a useful noninvasive method for the diagnosis of this disorder. In addition, we present a family in which 3 of 6 siblings were affected by ARVD, suggesting that some genetic factors may be involved in the etiology of this disorder.

Isolated right heart purulent pericarditis forming a large mediastinal mass

A 40-year-old man developed cardiomegaly with protrusion of the right heart border following staphylococcal endocarditis. Computed tomography of the chest revealed a large anterior mediastinal mass. Hemodynamic pressure curves presented features similar to those of constrictive pericarditis. At operation, 150 ml of purulent fluid was encapsulated within the thickened pericardium and separated from the rest of the pericardial sac. The encapsulated abscess was resected.

The development of the entire end-systolic pressure-volume and ejection fraction-afterload relations: a new concept of systolic myocardial stiffness

In this study we introduce a new concept of systolic myocardial stiffness that extends the Suga-Sagawa maximum ventricular elastance concept to the myocardium. End-systole is defined as the time of maximum systolic myocardial stiffness (max Eav), which we examined for its load independence and sensitivity to changes in the inotropic state and to heart rate. Seven adult mongrel dogs were instrumented with ultrasonic crystals for measurements of long and short axes and left ventricular wall thickness, and a high-fidelity micromanometer was inserted for measurement of left ventricular pressures. Preload and afterload were altered by inferior vena cava occlusion, nitroprusside, angiotensin II, atropine, propranolol, and various combinations with propranolol. End-systolic stress-strain relations (slope: max Eav) were linear in all seven dogs, implying that end-systolic myocardial stiffness is independent of end-systolic stress. Changes in max Eav (for constant preload and afterload) reflected changes in the ejection fraction; max Eav was also insensitive to propranolol and to changes in heart rate over the range from 120 to 180 beats/min. End-systolic pressure-volume relations (ESPVRs), derived analytically from these stress-strain relations, were nonlinear, and estimates of volume at zero stress (Vom) were always positive. On the other hand, ESPVRs obtained on the basis of the Suga-Sagawa maximum ventricular elastance concept, were linear, and volume at zero pressure (Vop) estimated by linear extrapolation was negative in one case. Based on the concept of systolic myocardial stiffness, the slope of the ESPVR varies with end-systolic volume and attains its maximum value (Emax) at zero end-systolic pressure. Normalization of Emax with Vom demonstrated a close relationship to max Eav. Thus both max Eav and Vom and Emax are ideal variables for assessing changes in myocardial contractility when preload and afterload are constant. Furthermore, Vom and max Eav permit development of the entire ejection fraction-afterload relationship for a given preload, thus providing a method for comparing myocardial contractile states between ventricles.

A beat-to-beat calculator for the diastolic pressure time index and the tension time index

We have developed a beat-to-beat calculator which can calculate in real-time the ratio of the diastolic pressure time index (DPTI), and the tension time index (TTI) as an index of the myocardial oxygen supply/demand balance. Physicians set up presumed value for the left ventricular endodiastolic pressure, a search area for the dicrotic notch, a threshold for the onset of the up-slope and the corresponding value of the calibration signal on the digital switches of the calculator. Next, the arterial pressure analog signal is input into the calculator. The calculator searches automatically for both the onset of the up-slope and the dicrotic notch. The arterial pressure curve is displayed beat-to-beat with the recognized onset and the dicrotic notch on the CRT to be confirmed by physicians. When physicians do not agree with the automatic recognition they can fit the automatic recognition to the observation. If the recognition of the onset is inadequate, the threshold can be re-adjusted to trigger the onset. If recognition of the dicrotic notch is inadequate, the physician can adjust the search-area. Therefore, physicians who operate the calculator can rely on the calculated DPTI/TTI. This calculator can continuously monitor the myocardial oxygen supply/demand balance in patients with acute myocardial infarction or just after open-heart surgery.

Application of end-systolic pressure-volume and pressure-wall thickness relations in conscious dogs

The usefulness of end-systolic measures of ventricular function was compared with that of standard contractility indexes in conscious dogs. End-systolic relations between left ventricular pressure and volume and between pressure and wall thickness were analyzed in dogs previously instrumented with ultrasonic crystals. Progressive angiotensin infusions were used to generate computer-averaged pressure-volume and pressure-wall thickness loops. Both relations were linear in every study and highly reproducible. With low and high dose dobutamine, the end-systolic pressure-volume relations were significantly displaced, with increased slope and inconsistent changes in intercept. This relation was more useful than the ejection fraction for detecting contractility increases at different afterloads, but it showed no advantage over maximal left ventricular dP/dt at all ranges of preload and afterload. The end-systolic pressure-volume relations were insensitive for detecting mild decreases in inotropic state produced by propranolol, and maximal dP/dt was superior for detecting such mild acutely reduced contractility. The end-systolic pressure-wall thickness relations showed displacement with dobutamine, although slope and intercept changes were not significant; these relations did not detect mild decreases in contractility produced by propranolol. It is concluded that the end-systolic pressure-volume relation and a simplified end-systolic measure using pressure and wall thickness provide sensitive, load-independent and reproducible approaches for defining acute increases in left ventricular contractility in conscious animals. Maximal dP/dt was equally effective for defining these increases in contractility and more sensitive for detecting slight acute decreases in contractility.

Experimental exercise-induced ischemia: drug therapy can eliminate regional dysfunction and oxygen supply-demand imbalance

The purpose of this study was to test the hypothesis that moderately severe exercise-induced regional myocardial ischemia can be prevented by combined pharmacologic intervention. Eight chronically instrumented dogs were studied using an ameroid constrictor to produce critical stenosis of the left circumflex coronary artery. The dogs were studied during steady state treadmill exercise that induced regional myocardial dysfunction (reduced systolic wall thickening; sonomicrometers) and ischemia (reduced subendocardial blood flow; microspheres). During a control exercise run, wall thickening in the ischemic posterior wall decreased from 21.4 to 13.3% whereas subendocardial blood flow failed to increase normally (36% of that in the normal zone). In the control anterior wall, both wall thickening and subendocardial blood flow increased significantly during the control run. Wall thickness-left ventricular pressure loop areas were calculated as an index of regional work; this index increased abruptly with the onset of exercise in both regions but became significantly depressed in the ischemic region during the steady state exercise. Therapy with a combination of atenolol (0.3 mg/kg body weight orally), diltiazem (0.3 mg/kg intravenously) and isosorbide dinitrate (2.0 mg/kg orally) effectively prevented regional myocardial ischemia and regional dysfunction. After drug therapy, wall thickening in the posterior wall increased from 17.3% at rest to 18.8% during exercise, and the regional transmural blood flow pattern was markedly improved. The initial overshoot of the regional work index during exercise was blunted by the drug therapy, and at steady state no differences between the ischemic and control regions were detected. Thus, combined drug therapy can eliminate exercise-induced regional myocardial ischemic dysfunction and appears to normalize the oxygen supply-demand imbalance.

Exercise-induced regional dysfunction with subcritical coronary stenosis

The hypothesis was tested that regional myocardial contractile dysfunction can detect subtle regional coronary blood flow maldistribution induced by exercise. In seven dogs, left ventricular pressure (micromanometer), regional systolic wall thickening (WTh, sonomicrometry), and myocardial blood flow (MBF, microspheres) were measured when mild degrees of coronary artery stenosis were produced during treadmill exercise. During exercise without coronary stenosis, WTh increased by 21 +/- 12% (SD), and transmural MBF increased uniformly. In each dog, two levels of coronary stenosis were produced during exercise by adjusting the coronary hydraulic cuff: (1) St-Ex I, where WTh during exercise failed to increase significantly (average change 0 +/- 7%), and (2) St-Ex II, where WTh during exercise decreased moderately from the resting control value (average -20 +/- 8%). In the potentially ischemic zone coronary hyperemia occurred with each run: resting subendocardial MBF was 1.09 +/- 0.30 mg/g/min, and it was 3.04 +/- 0.83 during control exercise, 2.48 +/- 0.75 during St-Ex I, and 1.55 +/- 0.59 ml/g/min during St-Ex II (p less than .01 compared with control exercise and control area). The subendocardial-subepicardial blood flow ratio fell from 1.32 +/- 0.27 during control exercise to 1.07 +/- 0.20 (p less than .05) during St-Ex I, and to 0.64 +/- 0.15 (p less than .01) with St-Ex II. Changes in the subendocardial electrogram and reactive hyperemia occurred more consistently during St-Ex II than St-Ex I. Thus, failure of regional function to increase during exercise detected slight maldistribution of regional MBF, whereas reduction of regional function during exercise of 10% or more below the resting value was a reliable marker of a regional flow defect and was always associated with other evidence of ischemia. Therefore, regional dysfunction during exercise can detect subcritical but functionally significant coronary stenosis, which may allow regional wall motion to be used for detecting coronary artery disease at a relatively early stage.

Preload reserve and mechanisms of afterload mismatch in normal conscious dog

Preload reserve and mechanisms of afterload mismatch were examined in 10 normal conscious dogs. The left ventricular (LV) pressure, wall thickness, and external major and minor axis diameters (sonomicrometry) were measured during sinus rhythm, and beat-averaged pressure-volume loops were generated. With maximum angiotensin II infusion, LV end-diastolic volume (EDV) increased by 13 +/- 2% (SEM), LV peak pressure (LVSP) increased by 44 +/- 6%, and stroke volume decreased by 12 +/- 3% (P less than 0.01), demonstrating an apparent descending limb of LV performance. With volume load alone, EDV increased by 9 +/- 2% from control (P less than 0.01), and stroke volume increased by 13 +/- 2%; mean wall stress during ejection was not increased, and heart rate and end-systolic pressure-volume relations showed no changes. To test whether the descending limb of function was due to maximum use of preload reserve or to inadequate venous return, angiotensin infusion was repeated during volume load. The descending limb relating LVEDV to stroke volume was always shifted upward and to the right after volume load, and the stroke volume at a comparable wall stress was 12 +/- 3% higher than during control angiotensin infusion (P less than 0.01). During pressure loading plus volume loading, the maximum EDV increase was 16 +/- 2%, and assuming unchanged afterload and end-systolic volume, an average maximum stroke volume reserve of 31 +/- 4% is calculated. 1) We conclude that sizable preload and stroke volume reserves exist in the normal resting dog; and 2) we describe a mechanism for the descending limb of LV performance curves produced by pressure loading in the intact circulation, which is related to inadequate venous return.

Effect of the combination of diltiazem and atenolol on exercise-induced regional myocardial ischemia in conscious dogs

The effect of combination therapy with diltiazem and atenolol on the regional myocardial blood flow-function relationship was studied in eight conscious dogs with chronic coronary artery stenosis. An ameroid constrictor and hydraulic occluder were placed around the left circumflex coronary artery, sonomicrometers were implanted for measuring wall thickness in control and ischemic regions, and regional myocardial blood flow was measured with the microsphere method. Eighteen days (average) after surgery, resting regional myocardial function and blood flow were normal, but treadmill exercise induced severe regional myocardial dysfunction in the posterior wall (wall thickening during systole reduced from 25.5% to 2.7%, a 90% reduction). Subendocardial blood flow decreased by 68% from the control standing value, while subepicardial flow increased. An identical exercise bout was performed 3 hr after administration of atenolol (1.0 mg/kg orally) and 15 min after administration of diltiazem (0.3 mg/kg iv). Heart rate during running was significantly lower as were left ventricular peak systolic pressure, end-diastolic pressure, and peak dP/dt. Wall thickening in the control region was not augmented during exercise after atenolol and diltiazem. There was less dysfunction in the ischemic region (35% reduction) and the improved performance was accompanied by a substantial increase in subendocardial perfusion (0.31 +/- 0.14 vs 0.61 +/- 0.30 ml/min/g, a 36% reduction from rest). Epicardial flow was unchanged, and the endocardial/epicardial ratio increased (0.27 +/- 0.13 vs 0.62 +/- 0.29). Recovery time for regional wall thickening also improved. The beneficial effects of the combination of atenolol and diltiazem in a preparation of single-vessel chronic coronary stenosis were shown to be significantly greater than those of either drug alone.

Effects of beta-blockade on regional myocardial flow and function during exercise

We examined the effects of a cardioselective beta-blocking drug on exercise-induced regional myocardial ischemia in 10 conscious dogs with chronic coronary artery stenosis. An ameroid constrictor, Doppler flowprobe, and hydraulic cuff were placed around the left circumflex coronary artery, and left ventricular pressure (LVP), systolic wall thickening (% delta WT; by sonomicrometry), and myocardial blood flow (MBF; microspheres) were measured during control standing, control treadmill exercise, and identical exercise after atenolol (1 mg/kg po). Prior to study, in every dog % delta WT and MBF in the ischemic area were normal at rest, indicating collateral development. During control exercise, % delta WT in the ischemic region markedly decreased from 27 to 4%, and transmural ischemia was evident in that region. Heart rate, systolic LVP, and LV (+)dP/dt were significantly lower during exercise after atenolol than during control exercise. % delta WT in the normal area was only 81% of that during control exercise, but dysfunction in the ischemic area was improved (77% increase compared with control exercise). Accompanying the improved function was a significant increase of MBF/beat and relative MBF in the ischemic zone; the endocardial-to-epicardial ratio increased from 0.27 to 0.47. Thus atenolol improved regional MBF distribution, thereby diminishing exercise-induced regional myocardial dysfunction and accelerating its recovery.

Effects of a calcium-entry blocker (diltiazem) on regional myocardial flow and function during exercise in conscious dogs

We examined the effects of diltiazem, a calcium-entry blocker, on exercise-induced myocardial ischemia in nine conscious dogs with chronic coronary stenoses. An ameroid constrictor, Doppler flow probe, and hydraulic occluder were placed around the left circumflex coronary artery, and left ventricular pressure was measured (Konigsberg micromanometer). Pairs of ultrasonic crystals were implanted for measuring left ventricular systolic wall thickening (% delta WTh) in control (left ventricular anterior wall) and ischemic (left ventricular posterior wall) regions, and regional myocardial blood flow was measured with the microsphere method. Eighteen days (average) after surgery mean coronary blood flow velocity had decreased and reactive hyperemic flow velocity after 10 sec of coronary occlusion was markedly reduced, but % delta WTh at rest remained normal, indicating collateral development. Control treadmill exercise was performed for 3.7 min (average), and 2 hr later administration of 0.3 mg/kg diltiazem was followed by an identical exercise bout. Control exercise increased % delta WTh in the normal region, while in the ischemic region % delta WTh decreased markedly and ischemia was evident (subendocardial flow, 0.29 +/- 0.12[SD] ml/min/g). After diltiazem hemodynamic and % delta WTh values at rest were not changed; during exercise the heart rate was significantly lower (204 +/- 24 vs 227 +/- 33 beats/min, p less than .01), but values for other hemodynamic measures were similar to those during the control run. % delta WTh in the control region was not changed during exercise after diltiazem, but compared with control exercise in the ischemic zone there was less dysfunction and subendocardial flow was greater. Recovery from exercise-induced dysfunction in the ischemic region occurred within 5 min, compared with over 30 min after control exercise. Thus, in a preparation of chronic coronary stenosis, the calcium-entry blocker improved the relationship between regional myocardial flow and function during exercise and led to more rapid recovery of regional myocardial dysfunction.

Evaluation of pulse contour methods in calculating stroke volume from pulmonary artery pressure curve (comparison with aortic pressure curve)

The reliability of five equations in assessing stroke volume from pulmonary artery pressure curves were critically evaluated in six dogs and in six patients. To alter stroke volume, isoproterenol, dobutamine, propranolol, lactate Ringer solution and artificial pacing were employed in the animal study and diltiazem (a calcium blocker) in the human study. A good correlation was found between the calculated and measured stroke volume (r = 0.80-0.86 in the animal study and r = 0.94-0.96 in the human study). The assessment of stroke volume from the pulmonary arterial pressure curves using equations was as good as that from the aortic pressure curves calculated simultaneously. These results suggest that the five equations may be clinically applicable for assessing stroke volume in critically ill patients. The employment of pulmonary arterial pressure curves in assessing stroke volume may be more useful clinically since its recording can be carried out more safely than recordings of aortic pressure curves.

Multiple atherosclerotic coronary aneurysms in association with acute myocardial infarction

A 60-year-old woman with multiple coronary aneurysms, complicated with acute infero-posterior myocardial infarction is presented. The cine-coronary arteriogram disclosed a diffuse dilatation of epicardial coronary arteries associated with multiple aneurysms, fusiform ones in the right coronary and the left circumflex coronary arteries and saccular ones in the left anterior descending coronary artery. Distal run-off was poor. Ventriculography revealed a decrease in the ejection fraction (36%) and segmental abnormal wall motion at the apical and infero-posterior regions. The cause of the aneurysms appeared to be atherosclerotic. We suggested that coronary embolization was the cause of acute myocardial infarction in this case.

Coronary arterial spasm in single coronary artery

A 48-year-old man developed severe chest pain and became unconscious. Coronary cineangiography revealed single coronary artery of the type L2b by Sharbaugh and White. Ergonovine, 0.2 mg i.v., produced coronary arterial spasm in the right coronary artery. This case suggests that coronary arterial spasm might be a cause of sudden death in patients with single coronary artery. However, an association of single coronary artery and coronary arterial spasm might be coincidental.

Long-lasting effect of oral molsydomine on exercise performance: a new antianginal agent

This study examines whether the beneficial effects of molsydomine, a recently introduced antianginal agent, on exercise performance of patients with angina pectoris are long lasting. The hemodynamic effects are known to persist for several hours. The effects of molsydomine on the duration of exercise and the time to the onset of ST depression were compared to those of placebo during two hours after oral administration. Molsydomine prolonged the duration of exercise in all eight patients (average 2.8 min, P less than 0.001) and delayed the onset of ST depression (average 2.2 min, P less than 0.001), while the placebo failed to alter these measurements. The increment of the duration of exercise produced by 2 mg of molsydomine in two hours following oral administration was comparable to the increment produced in a few minutes after 0.3 mg of nitroglycerin given sublingually. The results indicate that molsydomine offers prophylasis for angina pectoris that lasts at least two hours after oral administration.

Skin potential activity in rats, cats, and primates (including man): a phylogenetic point of view

With rats, cats, nonhuman primates, and humans serving as subjects, skin potential activity was measured under waking conditions. In good agreement with the findings of previous workers, skin potential response waveform was always monophasic negative in rats and cats, but in humans it took three forms. By contrast, it was always monophasic positive in simian nonhuman primates, although prosimiae gave monophasic negative waves. A skin potential level-skin potential response relationship could not be observed in any subject except humans. From these results, an attempt was made to relate skin potential activity to the peripheral mechanism involved in these species on the basis of a phylogenetic point of view.

Activational and behavioral aspects of spontaneous skin potential responses in rats

Spontaneous skin potential responses (spontaneous SPRs) were recorded from the foot pad of nonanesthetized and unrestrained rats. It was observed that frequency of spontaneous SPRs varied directly with the states of activation. A remarkable diminution of spontaneous SPRs was noted during the grooming and the face washing.