Relation between left ventricular global and regional function and extent of myocardial ischemia in the canine heart

Amaki, Makoto; Schneider, R; Mercier, Richard J.; Naccarella, F; Agarwal, Jai B.; Helfant, Richard H.; Weintraub, William S.

doi:10.1016/s0735-1097(85)80260-6

Cited by 28 publications

(12 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results seem to differ from those of the previous reports (Akaishi et al 1985;Noma et al 1988a, b;Ishikawa et al 1993;Sakuma et al 1993) which showed that the increase of the isovolumetric shortening in the non-ischemic region reflected the increase of the isovolumetric bulging in the ischemic region, both in the preload change and in the afterload change. The changes of the end-diastolic relations between the non-ischemic and ischemic regions partly affected the relationship between these two regions in the isovolumetric phase.…”

Section: Regional Wall Motion In the Isovolumetric Phasecontrasting

confidence: 96%

“…In regional ischemic heart, the effects of changes in preload, afterload and contractile state on regional wall motion have been reported (Akaishi et al 1985;Lew and Ban-Hayashi 1985;Noma et al 1988a, b;Ishikawa et al 1993;Sakuma et al 1993). It has been shown that the degree of isovolumetric shortening in the non-ischemic region reflects the degree of paradoxical systolic expansion in the ischemic myocardium.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of Tachycardia on Regional Wall Motion in Acute Ischemic Canine Heart

Yamamoto

Sakuma

Hozawa

et al. 2004

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

Tachycardia accompanies the preload reduction. Our aim is to assess the effect of the heart rate change on wall motion in ischemic heart. In 8 dogs with occlusion of left anterior descending artery, we changed the heart rate (heart rate 90, 120, and 150 beats/minute) after using UL-FS49, a selective bradycardic agent, with atrial pacing. Preload was changed by inferior vena caval occlusion at a heart rate of 90 beats/minute. With either an increase in heart rate or an inferior vena caval occlusion, the end-diastolic length was decreased, but the end-diastolic length relationships between the non-ischemic and the ischemic region made different lines from those of the heart rate change and inferior vena caval occlusion. When increasing the heart rate, isovolumetric shortening was unchanged in the non-ischemic region with more expansion in the ischemic region. While inferior vena caval occlusion at a heart rate of 90 beats/minute, isovolumetric shortening was increased in the non-ischemic region, with more expansion in the ischemic region. Both in tachycardia and by the inferior vena caval occlusion, ejectional shortenings decreased in the non-ischemic and ischemic regions. Our results suggest that, in ischemic heart, tachycardia changes both in the end-diastolic length relationship between the nonischemic and the ischemic region and at the isovolumetric contraction phase. The changes seem to be not only due to the inferior vena caval occlusion, but also due to tachycardia itself. heart rate; preload; isovolumetric phase; ischemic region; UL-FS49

show abstract

Section: Regional Wall Motion In the Isovolumetric Phasecontrasting

confidence: 96%

mentioning

confidence: 99%

Effects of Tachycardia on Regional Wall Motion in Acute Ischemic Canine Heart

Yamamoto

Sakuma

Hozawa

et al. 2004

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

show abstract

“…It is well recognized that regional ischemia results in local contractile dysfunction [5,6], which may or may not be reflected in a loss of global contractile function [24,25], The loss of local function while retaining global func tion has been reported by several investiga tors [5,6], In the present study, local function 40 Yokoyama/Novitzky/Deal/Snow T < and the Stunned Myocardium remained depressed despite recovery of global function, as measured by conventional pa rameters. e.g.…”

Section: Discussionsupporting

confidence: 49%

Facilitated Recovery of Cardiac Performance by Triiodothyronine following a Transient Ischemic Insult

Yokoyama

Novitzky²,

Deal³

et al. 1992

Cardiology

View full text Add to dashboard Cite

Reperfusion following a transient ischemic insult has been shown to result in a delayed recovery of myocardial function. A reduction in plasma triiodothyronine (T₃) has been reported in these acute cardiovascular challenges. To test whether the replacement of T₃ can facilitate the recovery of myocardial function following a transient regional ischemia, we investigated cardiac performance for 3 h after a 15-min, left anterior descending coronary artery occlusion in a canine model. Three groups of dogs were studied: I – control (n = 10); II -receiving T₃ (0.25 µg/kg i.v. and 0.25 µg/kg/h for 3 h, n = 9), and III – receiving T₃ (0.25 µg/kg i.v. and 0.5 µg/kg/h for 3 h, n = 9). Three hours following reperfusion, the T3 level in blood was significantly decreased in group I. Concomitantly, local segmental shortening was reduced from preocclusion control levels in group I (15.2 to 5.1%, p < 0.05), but recovered in both treated groups. The endsystolic elastance (Ees) and the external work (EW) efficiency (EW/PVA) in group I were depressed from preocclusion control (Ees = 95.5 ± 0.8%; EW/PVA = 90.2 ± 1.8%, both p < 0.05), the effective arterial elastance (Ea) and ventriculoarterial coupling (Ea/Ees) in group I were still elevated from preocclusion control (Ea = 122.5 ± 5.1%; Ea/Ees =128.3 ± 5.3%, both p < 0.05). But these measures of global cardiac performance in the treated groups recovered following reperfusion, and the extent of recovery was dose dependent. These data suggest that T₃ facilitates recovery of the stunned myocardium by improvement in local and global contractile function, in ventriculoarterial coupling, and in the energy efficiency.

show abstract

“…As seen from the tracing of ischemic segment length during coronary occlusion, the motion of the acutely ischemic myocardium was characterized by lenthening (bulging) in early systole, slowly decreasing length in mid-systole, rapidly decreasing length (recoil) in early diastole, and slowly increasing length in the remainder of diastole. In the nonischemic zone, the EDL increased and showed increased shortening (Akaishi et al, 1985b), and chamber diameter showed increased end-diastolic dimension and decreased shortening (Akaishi et al, 1985a) after coronary occlusion. With blood with- Abbreviations: Subendo = subendocardial blood flow (ml/min per g); Subepi • flow (ml/min per g); Mid = mid-myocardial blood flow (ml/min per g).…”

Section: Myocardial Blood Flow (Table 2)mentioning

confidence: 99%

“…One crystal pair at each site was implanted subendocardially in a circumferential plane for measurement of segment length (Weintraub et al, 1981). In three dogs, a pair of ultrasonic crystals was implanted on the anterior and posterior endocardial surfaces through an incision in the LV apex to measure the LV anteriorposterior minor axis internal diameter, as described previously (Akaishi et al, 1985a). Pacing electrodes were sutured to the left atrial appendage.…”

mentioning

confidence: 99%

Analysis of systolic bulging. Mechanical characteristics of acutely ischemic myocardium in the conscious dog.

Amaki¹,

Weintraub²,

Schneider³

et al. 1986

Circulation Research

View full text Add to dashboard Cite

SUMMARY. To determine the mechanical factors affecting regional segmental motion after acute coronary occlusion, we studied seven conscious dogs, instrumented with sonomicrometers. Loading conditions were changed by the withdrawal of 500 ml of blood and the transfusion of 800 ml of blood. To express segmental motion, percent systolic shortening, percent systolic elongation, and early diastolic shortening were calculated. Blood withdrawal decreased left ventricular preload, increased percent systolic elongation (from 6.9 ± 3.1% to 9.9 ± 3.5%) and early diastolic shortening (12.9 ± 5.3% to 16.6 ± 5.3%), and decreased percent systolic shortening. Blood transfusion increased left ventricular preload, decreased percent systolic elongation (to 5.2 ± 1.8%) and early diastolic shortening (8.8 ± 2.9%), and increased percent systolic shortening. Manipulation of loading did not change regional myocardial blood flow. In acutely ischemic myocardium, the tension-length loop showed an exponential upstroke during isovolumic systole and a nearly superimposed exponential downsrroke during the isovolumic relaxation phase after systole, compatible with essentially passive movement as seen with an elastic material. The changes in loading conditions affected the tension-length curve to a very minor extent. The uniformity of the curve and its exponential shape explain the load-dependency of systolic bulding and segmental motion. It is concluded that systolic bulging depends on the change in the preload tension due to the compliant portion of tension-length curve, and that shortening of ischemic myocardium during the isovolumic relaxation phase is a completely passive phenomenon. (Circ Res 58: 209-217, 1986)

show abstract

Relation between left ventricular global and regional function and extent of myocardial ischemia in the canine heart

Cited by 28 publications

References 30 publications

Effects of Tachycardia on Regional Wall Motion in Acute Ischemic Canine Heart

Effects of Tachycardia on Regional Wall Motion in Acute Ischemic Canine Heart

Facilitated Recovery of Cardiac Performance by Triiodothyronine following a Transient Ischemic Insult

Analysis of systolic bulging. Mechanical characteristics of acutely ischemic myocardium in the conscious dog.

Contact Info

Product

Resources

About