Continuous measurement of left ventricular volume in animals and humans by conductance catheter.

Baan, Jan; Velde, Enno T. van der; Bruin, Hein G. de; Smeenk, G; Koops, J.; Dijk, Arjan D. van; Temmerman, D; Senden, Joan M.; Buis, Beert

doi:10.1161/01.cir.70.5.812

Cited by 847 publications

(575 citation statements)

References 13 publications

Supporting

Mentioning

564

Contrasting

Unclassified

Order By: Relevance

“…The catheter provided simultaneous proximal aortic and ventricular cavity micromanometer pressures and chamber volume, the latter by conductance method. 7,8 Catheter volume was calibrated by matching to steady-state echo-derived end-diastolic and end-systolic dimensions (Simpson's method).…”

Section: Catheterization Protocolmentioning

confidence: 99%

Short-Term Effects of Right-Left Heart Sequential Cardiac Resynchronization in Patients With Heart Failure, Chronic Atrial Fibrillation, and Atrioventricular Nodal Block

Hay¹,

Melenovský²,

Fetics³

et al. 2004

Circulation

114

View full text Add to dashboard Cite

Background-Single-site ventricular pacing in patients with heart failure, atrial fibrillation, and severe atrioventricular (AV) nodal block risks the generation of discoordinate contraction. Whether altering the site of stimulation can offset this detrimental effect and what role sequential right ventricular-left ventricular (RV-LV) stimulation might play in such patients remain unknown. Methods and Results-Nine subjects with heart failure (ejection fraction, 14% to 30%), atrial fibrillation, and AV block were studied by pressure-volume analysis. Ventricular stimulation was applied to the RV (apex and outflow tract), LV free wall, and biventricular (BiV) at 80 and 120 bpm. BiV improved systolic function more than either site alone (dP/dt max , 810Ϯ83, 924Ϯ98, 983Ϯ102 mm Hg/s for RV, LV, BiV, respectively; PϽ0.05), although LV pacing was significantly better than RV pacing. However, only BiV improved diastolic function (isovolumic relaxation) over RV or LV alone. Similar results were obtained for both heart rates. RV pacing site did not alter the BiV effect, and concomitant stimulation of both RV sites did not improve function over each alone. Finally, varying RV-LV delay revealed optimal responses with simultaneous pacing. Conclusions-Simultaneous BiV pacing acutely enhances both systolic and diastolic function over single-site RV or LV pacing in congestive heart failure patients with atrial fibrillation and advanced AV block. Sequential RV-LV stimulation offers minimal benefit on average and should perhaps be considered only in targeted subsets such as nonresponding patients.

show abstract

Section: Catheterization Protocolmentioning

confidence: 99%

Short-Term Effects of Right-Left Heart Sequential Cardiac Resynchronization in Patients With Heart Failure, Chronic Atrial Fibrillation, and Atrioventricular Nodal Block

Hay¹,

Melenovský²,

Fetics³

et al. 2004

Circulation

114

View full text Add to dashboard Cite

show abstract

“…11,12 In brief, saturated saline (1 to 2 mL) was rapidly injected into the main pulmonary artery to obtain the parallel conductance, the contribution of surrounding structures. The parallel conductance was repeatedly measured at the beginning of each protocol.…”

Section: Preparationmentioning

confidence: 99%

“…Difficulties include the need for a precise high-fidelity left ventricular (LV) volume curve as well as the need for multiple pressure-volume (P-V) loops under various loading conditions. Introduction of the conductance catheter 9,11,12 and of the concept of a hydromotive pressure source 13,14 for single-beat E es estimation has partly solved these difficulties. Mirsky et al 15,16 developed a single-beat method to assess myocardial contractility by fitting a model to late systolic data and estimating the unstressed state.…”

mentioning

confidence: 99%

Single-Beat Estimation of End-Systolic Elastance Using Bilinearly Approximated Time-Varying Elastance Curve

et al. 2000

View full text Add to dashboard Cite

Background-Although left ventricular end-systolic elastance (E es ) has often been used as an index of contractility, technical difficulties in measuring volume and in changing loading conditions have made its clinical application somewhat limited. By approximating the time-varying elastance curve by 2 linear functions (isovolumic contraction phase and ejection phase) and estimating the slope ratio of these, we developed a method to estimate E es on a single-beat basis from pressure values, systolic time intervals, and stroke volume. Methods and Results-In 11 anesthetized dogs, we compared single-beat E es with that obtained with caval occlusion.Although the decrease (but not the increase) in contractility (5.3 to 11.4 mm Hg/mL) and the change in loading conditions (3.7 to 34.0 mm Hg/mL) over wide ranges significantly altered the slope ratio, the estimation of E es was reasonably accurate (yϭ0.97xϩ0.46, rϭ0.929, SEEϭ2.1 mm Hg/mL). Conclusions-E es can be estimated on a single-beat basis from easily obtainable variables by approximating the time-varying elastance curve by a bilinear function.

show abstract

“…Briefly, the catheter measured continuously the timevarying electrical conductance G(t) of the blood within the LV cavity of the beating heart [5,6]. Our custom-made signal conditioner-processor (SI Medicotech Co., Ltd., Osaka, Japan) converted the G(t) to LV conductance volume after calibrating blood conductivity in the sampling cuvette.…”

Section: Surgical Preparationmentioning

confidence: 99%

“…We obtained the parallel conductance Gp attributable to the conductance of the LV wall and the surrounding tissues and fluid by the standard hypertonic saline dilution method. From this Gp, we calculated a constant offset volume (Vc) and obtained the absolute LVV by subtracting Vc from the LV conductance volume [5,6].…”

Section: Surgical Preparationmentioning

confidence: 99%

Mode of frequency distribution of external work efficiency of arrhythmic beats during atrial fibrillation remains normal in canine heart

et al. 2008

View full text Add to dashboard Cite

The external work (EW) efficiency of individual arrhythmic beats of the left ventricle (LV) cannot directly be obtained since LV O 2 consumption (VO 2 ) of each beat cannot directly be measured under beat-to-beat varying contractile and loading conditions. We, however, have recently reported that VO 2 of each arrhythmic beat can reasonably be estimated by VO 2 = aPVA ? bE max ? c even under varying PVA and E max . Here, PVA is the LV pressure-volume (P-V) area as a measure of the LV total mechanical energy, E max is the LV end-systolic elastance as an index of the LV contractility, a is a constant O 2 cost of PVA, b is a constant O 2 cost of E max , and c is the basal metabolic VO 2 of the beat, all on a per-beat basis. Using the above formula in this study, we calculated VO 2 of the individual arrhythmic beats from their measured PVA and E max during electrically induced atrial fibrillation (AF) in normal canine hearts. We then calculated their LV EW efficiency by dividing their measured EW with the estimated VO 2 . We found that the thus calculated EW efficiency of the arrhythmic beats had a rightward skewed distribution with a mode of 15% and a maximum of 18% around a mean of 13% on average in six hearts. This mode remained comparable to the efficiency (15%) at regular tachycardia though 22% lower than mean arrhythmic tachycardia.

show abstract

Continuous measurement of left ventricular volume in animals and humans by conductance catheter.

Abstract: An eight-electrode conductance catheter previously developed by us and used to determine stroke volume in dogs was applied in human beings and dogs to measure absolute left ventricular volume quantitatively. For calibration we developed the formula V(t) = (l/a)(L2/Yb)G(t) -

Cited by 847 publications

References 13 publications

Short-Term Effects of Right-Left Heart Sequential Cardiac Resynchronization in Patients With Heart Failure, Chronic Atrial Fibrillation, and Atrioventricular Nodal Block

Short-Term Effects of Right-Left Heart Sequential Cardiac Resynchronization in Patients With Heart Failure, Chronic Atrial Fibrillation, and Atrioventricular Nodal Block

Single-Beat Estimation of End-Systolic Elastance Using Bilinearly Approximated Time-Varying Elastance Curve

Mode of frequency distribution of external work efficiency of arrhythmic beats during atrial fibrillation remains normal in canine heart

Contact Info

Product

Resources

About