How to quantify pump function of the heart. The value of variables derived from measurements on isolated muscle.

Elzinga, G; Westerhof, Nico

doi:10.1161/01.res.44.3.303

Cited by 90 publications

(21 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ventricular power output (VPO) was calculated by the formula: VPO = SW * heart rate (5) Normalized minor axis circumferential stroke work was calculated as: SW = fc de (6) 996 and myocardial power output (MPO) was calculated as: MPO = heart rate*fcde (7) where 6 was circumferential midwall equatorial wall stress, and E was circumferential midwall equatorial strain (see Appendix). Left Ventricular End DiastolicVolume(r FIGURE 3.…”

Section: Methodsmentioning

confidence: 99%

Linearity of the Frank-Starling relationship in the intact heart: the concept of preload recruitable stroke work.

Glower¹,

Spratt²,

Snow³

et al. 1985

Circulation

813

420

View full text Add to dashboard Cite

The Frank-Starling relationship generally has been examined with filling pressure as the index of preload, resulting in a curvilinear function that plateaus at higher filling pressures. To investigate this relationship further in the intact heart, 32 dogs were chronically instrumented with left ventricular and pleural micromanometers and with regional (10 dogs) or global (22 dogs) ultrasonic dimension transducers. Seven days after implantation, left ventricular pressure and regional or global dimensions were recorded in the conscious state. After autonomic blockade, preload was varied by vena caval occlusion. Myocardial function was assessed by calculating regional or global stroke work, and preload was measured as end-diastolic segment length or chamber volume. The relationship between stroke work and either end-diastolic segment length or chamber volume (termed the preload recruitable stroke work relationship) was highly linear in every study (mean r = .97) and could be quantified by a slope (Mw) and x-intercept (L,). Previous nonlinear relationships between stroke work and filling pressure seemed to reflect the exponential diastolic pressure-volume curve. Over the physiologic range of systolic arterial pressures produced by infusion of nitroprusside or phenylephrine, no significant change was observed in Mw or Lw in the normal dog. Calcium infusion increased both regional and global M, by 71 + 19% and 65 + 9%, respectively (p < .02), with no significant change in LW. To normalize for ventricular geometry and heart rate, stroke work was computed from circumferential stress-strain data and converted to myocardial power output, which was then plotted against enddiastolic circumferential strain. This relationship also was highly linear, and the slope, Mmp (mW/cm3 of myocardium), is proposed as a potential measure of intrinsic myocardial performance independent of loading, geometry, and heart rate. Circulation 71, No. 5, 994-1009, 1985 QUANTIFICATION of cardiac function has been the goal of physiologists for nearly a century, but it has been difficult if not impossible to establish practical or reliable measures of intrinsic myocardial performance in the intact heart. Some indexes, such as ventricular function curves relating stroke work to filling pressures, were nonlinear and difficult to quantify.' Other parameters suffered from lack of preload or afterload From the

show abstract

Section: Methodsmentioning

confidence: 99%

Linearity of the Frank-Starling relationship in the intact heart: the concept of preload recruitable stroke work.

Glower¹,

Spratt²,

Snow³

et al. 1985

Circulation

813

420

View full text Add to dashboard Cite

show abstract

“…d) Decrease in pulmonary vascular resistance (PVR). An alternative approach for describing heart function is the pump-function graph [20]. Here, average RV pressure versus stroke volume (SV) at steady state are plotted (the working point) and by the same single-beat estimation (Piso), a pump-function graph is constructed (-----).…”

Section: How Can We Distinguish the Cardiac-specific Effects Of Pah Tmentioning

confidence: 99%

“…Pump-function graph An interesting alternative for studying cardiac-specific versus pulmonary-specific effects is the pump-function graph [20,22]. A major advantage of this method is that only instantaneous pressure and average flow measurements suffice, and that its analysis does not require instantaneous volume signals.…”

Section: How Can We Distinguish the Cardiac-specific Effects Of Pah Tmentioning

confidence: 99%

Perspectives on novel therapeutic strategies for right heart failure in pulmonary arterial hypertension: lessons from the left heart

Handoko

Man

Allaart³

et al. 2010

Eur Respir Rev

111

View full text Add to dashboard Cite

Right heart function is the main determinant of prognosis in pulmonary arterial hypertension (PAH). At present, no treatments are currently available that directly target the right ventricle, as we will demonstrate in this article.Meta-analysis of clinical trials in PAH revealed that current PAH medication seems to have limited cardiac-specific effects when analysed by the pump-function graph. Driven by the hypothesis that ''left'' and right heart failure might share important underlying pathophysiological mechanisms, we evaluated the clinical potential of left heart failure (LHF) therapies for PAH, based on currently available literature.As in LHF, the sympathetic nervous system and the renin-angiotension-aldosterone system are highly activated in PAH. From LHF we know that intervening in this process, e.g. by angiotensinconverting enzyme inhibition or b-blockade, is beneficial in the long run. Therefore, these medications could be also beneficial in PAH. Furthermore, the incidence of sudden cardiac death in PAH could be reduced by implantable cardioverter-defibrillators. Finally, pilot studies have demonstrated that interventricular dyssynchrony, present at end-stage PAH, responded favourably to cardiac resynchronisation therapy as well.In conclusion, therapies for LHF might be relevant for PAH. However, before they can be implemented in PAH management, safety and efficacy should be evaluated first in well-designed clinical trials.

show abstract

“…A pump function graph presents the pumping ability of the RV. ELZINGA and WESTERHOF [16,17] have shown, in isolated cat hearts, that the pump function of the left and right heart can be described quantitatively by such a graph, which relates mean ventricular pressure with mean ventricular output. This relationship, which characterises the heart, was determined by making the heart eject against a series of different arterial loads.…”

Section: Right Ventricular Contractility In Sscpah Mj Overbeek Et Almentioning

confidence: 99%

Right ventricular contractility in systemic sclerosis-associated and idiopathic pulmonary arterial hypertension

Overbeek¹,

Lankhaar²,

Westerhof³

et al. 2008

Eur Respir J

View full text Add to dashboard Cite

Since systemic sclerosis (SSc) also involves the heart, the aim of the present study was to evaluate possible differences in right ventricular (RV) pump function between SScassociated pulmonary arterial hypertension (PAH; SScPAH) and idiopathic PAH (IPAH).In 13 limited cutaneous SScPAH and 17 IPAH patients, RV pump function was described using the pump function graph, which relates mean RV pressure (PRV) and stroke volume index (SVI). Differences in pump function result in shift or rotation of the pump function graph. PRV and SVI were measured using standard catheterisation. The hypothetical isovolumic PRV (PRV,iso) was estimated using a single-beat method. The pump function graph was approximated by a parabola:, where SVImax is the hypothetical maximal SVI at zero PRV, enabling calculation of SVImax. There were no differences in SVI and SVImax. Both PRV and PRV,iso were significantly lower in SScPAH than in IPAH (PRV 30.7¡8.5 versus 41.2¡9.4 mmHg; PRV,iso 43.1¡12.4 versus 53.5¡10.0 mmHg). Since higher pressures were found at similar SVI, the difference in the pump function graph results from lower contractility in SScPAH than in IPAH.Right ventricular contractility is lower in systemic sclerosis-associated pulmonary arterial hypertension than in idiopathic pulmonary arterial hypertension.

show abstract

How to quantify pump function of the heart. The value of variables derived from measurements on isolated muscle.

Cited by 90 publications

References 54 publications

Linearity of the Frank-Starling relationship in the intact heart: the concept of preload recruitable stroke work.

Linearity of the Frank-Starling relationship in the intact heart: the concept of preload recruitable stroke work.

Perspectives on novel therapeutic strategies for right heart failure in pulmonary arterial hypertension: lessons from the left heart

Right ventricular contractility in systemic sclerosis-associated and idiopathic pulmonary arterial hypertension

Contact Info

Product

Resources

About