1
|
Re-visiting the Frank-Starling nexus. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 159:10-21. [DOI: 10.1016/j.pbiomolbio.2020.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/19/2020] [Accepted: 04/09/2020] [Indexed: 11/24/2022]
|
2
|
Han JC, Pham T, Taberner AJ, Loiselle DS, Tran K. Solving a century-old conundrum underlying cardiac force-length relations. Am J Physiol Heart Circ Physiol 2019; 316:H781-H793. [PMID: 30707611 DOI: 10.1152/ajpheart.00763.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In the late 19th century, Otto Frank presented a diagram (Frank O. Z Biol 37: 483-526, 1899) showing that cardiac end-systolic pressure-volume relations are dependent on the mode of contraction: one for isovolumic contractions that locate above that for afterloaded ejecting contractions. Conflicting results to Frank's have been subsequently demonstrated in various species, both within and among preparations, ranging from the whole hearts to single myocytes, showing a single pressure-volume or force-length relation that is independent of the mode of contraction. Numerous explanations for these conflicting results have been proposed but are mutually contradictory and hence unsatisfying. The present study aimed to explore how these conflicting findings can be reconciled. We thus explored the cardiac force-length relation across a wide spectrum of both preloads and afterloads, encompassing the physiological working range. Experiments were performed using isolated ventricular trabeculae at physiological temperature and stimulus frequency. The force-length relation obtained from isometric contractions was indeed located above a family of those obtained from shortening contractions. Low preload conditions rendered the relation contraction mode independent. High afterload conditions also showed a comparable effect. Our exploration allowed us to reveal the loading conditions that can explain the apparent single, contraction mode-independent, force-length relation that is in contrast with that presented by Frank. Resolving this century-old cardiac conundrum highlights the caution that must be taken when using the end-systolic force-length relation to illustrate as well as to understand the concepts of the Frank-Starling law of the heart, "potential energy," and cardiac contractility. NEW & NOTEWORTHY Our exploration of the cardiac force-length relation under wide ranges of preload and afterload has allowed us to reconcile conflicting results in the literature regarding its length dependency. We show that the relation is dependent on the mode of contraction but can appear to be otherwise under certain conditions. This finding highlights the need for caution when using the force-length relation to understand key concepts in cardiac physiology.
Collapse
Affiliation(s)
- June-Chiew Han
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand
| | - Toan Pham
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand.,Department of Physiology, University of Auckland , Auckland , New Zealand
| | - Andrew J Taberner
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand.,Department of Engineering Science, University of Auckland , Auckland , New Zealand
| | - Denis S Loiselle
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand.,Department of Physiology, University of Auckland , Auckland , New Zealand
| | - Kenneth Tran
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand
| |
Collapse
|
3
|
Affiliation(s)
| | - Kern Wildenthal
- Pauline and Adolph Weinberger Laboratory for Cardiopulmonary Research, University of Texas Southwestern Medical School, Dallas, Texas 75235, USA
| |
Collapse
|
4
|
Yasumura Y, Nozawa T, Futaki S, Tanaka N, Suga H. Ejecting activation differs in energetics from ordinary positive inotropism in the canine left ventricle. Heart Vessels 1994; 9:129-39. [PMID: 8056719 DOI: 10.1007/bf01745238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Ventricular ejection is known to have dual effects on the end-systolic pressure: the ejecting deactivation by a relatively large ejection against a low afterload versus the ejecting activation by a relatively small ejection against a high afterload. We studied how the increase in contractility index (Emax) by the ejecting activation would affect myocardial oxygen consumption (VO2). To this end, left ventricular steady-state ejecting contractions were produced with various stroke volumes from a fixed end-diastolic volume in an excised cross-circulated canine heart. The effect of the ejection-activated Emax on VO2 was assessed by the relation between VO2 and pressure-volume area (PVA). PVA is the total mechanical energy generated by ventricular contraction. In contrast to the elevation of the linear VO2-PVA relation in a parallel manner with an enhanced Emax by ordinary positive inotropic agents such as catecholamines and calcium, the ejection-activated Emax did not elevate the VO2-PVA relation. This result indicates that the ejecting activation enhances Emax in an energetically different manner from ordinary positive inotropism in the canine left ventricle.
Collapse
Affiliation(s)
- Y Yasumura
- Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Osaka, Japan
| | | | | | | | | |
Collapse
|
5
|
Carabello BA. The role of end-systolic pressure-volume analysis in clinical assessment of ventricular function. Trends Cardiovasc Med 1991; 1:337-41. [DOI: 10.1016/1050-1738(91)90071-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
6
|
Jacob R, Kissling G. Ventricular pressure-volume relations as the primary basis for evaluation of cardiac mechanics. Return to Frank's diagram. Basic Res Cardiol 1989; 84:227-46. [PMID: 2669727 DOI: 10.1007/bf01907971] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Considering ventricular function from the vantage point of the pressure-volume (P-V) diagram permits not only quantification of ventricular working capacity under normal and pathophysiological conditions but also promotes understanding of cardiac dynamics including prediction of the effects of mechanical and pharmacological interventions. Therefore it seems appropriate, at least intellectually, to classify all measured volume and pressure data into the scheme of the P-V diagram. The use of so-called contractility indices and also the restriction to the end-systolic P-V relation alone means deliberate renunciation of important information. In principle, Frank's original concept can be confirmed which, under afterloaded conditions, implies the existence of distinct end-systolic P-V curves each related to a particular end-diastolic volume. As an approximation, however, the assumption of one common end-systolic P-V relation seems tolerable. Based on Frank's diagram, a concept for assessment of ventricular and myocardial function is presented following a discussion of the determinants of the diastolic and end-systolic P-V relations, as well as the methodological difficulties and different notions with regard to the end-systolic P-V curve. The P-V area between the curves of systolic maxima and diastolic minima, up to a defined end-diastolic pressure, is recommended as a measure for quantitative evaluation of ventricular working capacity. Transformation into stress-length (sigma-l) relations is indispensable for assessment of myocardial function under the conditions of changed ventricular geometry. The normalized sigma-l area yields a measure for interindividual evaluation of myocardial working capacity. This concept of evaluation does not mean acknowledgement of the visco-elastic theory of muscle contraction nor of the Emax concept. The P-V and sigma-l relations must, however, be complemented by time related parameters in order to estimate ventricular and myocardial power capacity. After a long-lasting search through international literature for "contractility indices" of general applicability and significance it seems appropriate to return to Frank's diagram as the primary basis for evaluating cardiac mechanics.
Collapse
Affiliation(s)
- R Jacob
- Physiologisches Institut II, Universität Tübingen, FRG
| | | |
Collapse
|
7
|
Gillebert TC, Sys SU, Brutsaert DL. Influence of loading patterns on peak length-tension relation and on relaxation in cardiac muscle. J Am Coll Cardiol 1989; 13:483-90. [PMID: 2913122 DOI: 10.1016/0735-1097(89)90529-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To analyze the influence of loading patterns on cardiac pump performance and cardiac relaxation [corrected], the effects of preload on peak length-tension relation [corrected] and of systolic load clamps on peak length-tension relation and on relaxation were analyzed in isolated cat papillary muscles. Preload reduction and early loading clamps induced a shift to the left of the peak length-tension relation, that is, a smaller muscle length for the same tension at peak shortening. Unloading clamps induced a shift to the right of the peak length-tension relation, that is, a larger muscle length for the same tension at peak shortening. The effects of load clamps on relaxation depended on when they were applied during isotonic shortening. Changes induced by load clamps could not be summarized in terms of enhanced or delayed relaxation, illustrating that shortening duration, isometric tension decline and isotonic lengthening have different determinants. In conclusion, not only peak or mean systolic pressure but also the entire loading pattern has to be taken into account whenever pressure-volume data or relaxation variables are interpreted.
Collapse
Affiliation(s)
- T C Gillebert
- Department of Physiology and Medicine, University of Antwerp, Belgium
| | | | | |
Collapse
|
8
|
Affiliation(s)
- D A Kass
- Division of Cardiology, Johns Hopkins University Hospital, Baltimore, MD 21205
| | | |
Collapse
|
9
|
Similarity and Dissimilarity Between Muscle Force-Length Relationship and Ventricular Pressure-Volume Relationship. ACTA ACUST UNITED AC 1988. [DOI: 10.1007/978-94-009-1313-4_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
10
|
de Jongste JC, Mons H, van Strik R, Bonta IL, Kerrebijn KF. Comparison of isometric and isotonic responses of human small airway smooth muscle in vitro. JOURNAL OF PHARMACOLOGICAL METHODS 1987; 17:165-71. [PMID: 3295398 DOI: 10.1016/0160-5402(87)90027-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The difference between isometric and isotonic responses of human small airway smooth muscle to a number of pharmacological agonists was studied. The isotonically measured sensitivity to methacholine was 1.4 times less than the isometrically measured value (p less than 0.05), and similar small discrepancies were found for histamine, leukotriene, prostaglandin F2 alpha, isoproterenol, and theophylline. Maximal isometric force and isotonic shortening after methacholine were linearly related (p less than 0.01). The between-methods difference is relatively small. Because the difference was of similar magnitude and in the same direction in all tissues studied, it is of little practical importance for conventional pharmacological experiments.
Collapse
|
11
|
Gülch RW. The concept of "end-systolic" pressure-volume and length-tension relations of the heart from a muscle physiologist's point of view. Basic Res Cardiol 1986; 81 Suppl 1:51-7. [PMID: 3790044 DOI: 10.1007/978-3-662-11374-5_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
End-systolic length-tension relationships were measured on ultrathin isolated heart preparations of rat (mean diameter +/- S.D. = 96 microns +/- 45 microns). Independent of contractile state being changed by variation in extracellular Ca++-concentration no unique end-systolic length-tension relation was found when varying pre- and afterload over a wide range. It is more likely that rectilinear end-systolic curves can be obtained under a low contractile state than under a high one. Thus, the muscle physiological basis is withdrawn from the Emax-concept for which a single end-systolic pressure-volume relation is typical.
Collapse
|
12
|
Abstract
Complete length-tension diagrams of myocardium were measured on isolated papillary muscles of cat right ventricle. These diagrams clearly demonstrate that irrespective of loading conditions there is no uniform maxima curve. As a function of preload the curves of afterloaded isotonic maxima obey totally separate nonlinear relations. Thus, for the heart muscle one should not assign a single linear regression line to the end-systolic length-tension points. Originally, its slope was supposed to be determined almost entirely by the contractile state of the heart muscle. Alteration in the contractile state of the heart muscle by varying the extracellular Ca++ concentration is primarily expressed in a corresponding change in the distance between maxima curve and resting length-tension curve, and thereby in the myocardial working capacity, whereas the mean slope of the maxima curves reacts in a considerably less sensitive manner. These evidences annul the supposed physiological basis of the end-systolic pressure-volume concept, with Emax as index of contractility.
Collapse
|
13
|
|
14
|
Nivatpumin T, Katz S, Scheuer J. Peak left ventricular systolic pressure/end-systolic volume ratio: a sensitive detector of left ventricular disease. Am J Cardiol 1979; 43:969-74. [PMID: 433779 DOI: 10.1016/0002-9149(79)90361-8] [Citation(s) in RCA: 145] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
15
|
|
16
|
Abstract
This article has attempted to summarize the current status of the therapeutic use of vasodilator drugs in acute and chronic heart failure. It is apparent from the increasing number of publications in this area that this alternative to more standard forms of therapy is likely to find a permanent and important place in the management of patients with heart disease. It should also be apparent that ideal drugs for the therapy of chronic heart failure are not yet available. Nevertheless, it is probable that such drugs will emerge and become at least as important as the routine use of digitalis in such patients.
Collapse
|
17
|
Gülch RW, Jacob R. The effect of sudden stretches on length-tension-and force-velocity relations of mammalian cardiac muscle. Pflugers Arch 1975; 357:335-47. [PMID: 1238995 DOI: 10.1007/bf00585987] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In the isotonically beating cat papillary muscle, a sudden augmentation of the preload initiates a visco-elastic strain retardation, in the course of which the preparations show a marked increase in their isotonic mechanogram amplitudes. It is preceded in the first seconds by a short-term decline. These effects correspond well with the phenomena of stress relaxation. When applying these post-stretch phenomena to the length-tension diagram, it is shown that the isometric and isotonic length-tension curves are significantly shifted to greater distances with respect to the resting length-tension curve, involving even a doubling of the myocardial working capacity in certain cases. Stretch-induced alterations in Vmax which were obtained from damped quick-releases, initiated during isometric contractions are almost negligible. On the other hand Vmax obtained from quick-releases which were started immediately after the onset of isotonic contractions are strongly affected by sudden stretches. The stair-like decline of the mechanograms in the initial phase of relaxation or retardation is assumed to be mediated by a stretch-induced alteration in the time course of the action potential. The additional reduction in myocardial performance superimposed on this, is consistent with the hypothesis of a stretch-induced transient inactivation or a delayed activation of contractile interaction sites.
Collapse
|
18
|
Gülch RW, Jacob R. Length-tension diagram and force-velocity relations of mammalian cardiac muscle under steady-state conditions. Pflugers Arch 1975; 355:331-46. [PMID: 1239721 DOI: 10.1007/bf00579854] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Length-tension diagrams and force-velocity relations of isolated cat papillary muscles were measured under strictly stationary conditions: any analysis of isometric mechanograms was carried out only in stable isometric beats; each measurement in beats under any condition different from the isometric one was determined in the very first contraction after a period of stabilization under isometric conditions. The length-tension diagrams show a clear distinction between isometric and isotonic length-tension curves. Force-velocity curves on the basis of afterloaded isotonic, as well as of damped quick-release contractions, could be satisfactorily approximated by a polynomial of the 5th order. Vmax estimated on the basis of afterloaded and of damped quick-releases in the course of isometric and isotonic contractions, was significantly dependent on preload. This is also valid in a range of muscle length which is regarded as physiological.
Collapse
|
19
|
Kissling G, Jacob R. [Factors limiting increase of stroke volume by positive inotropism. Studies on sufficient hearts under continous postextrasystolic potentiation]. Pflugers Arch 1972; 335:153-66. [PMID: 4117043 DOI: 10.1007/bf00592042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
20
|
Crawford DW, Barndt R, Harrison EC, Lau FY. A model for estimating some of the effects of aneurysm resection following myocardial infarction: preliminary clinical confirmation. Chest 1971; 59:517-23. [PMID: 4952550 DOI: 10.1378/chest.59.5.517] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
|
21
|
Lewi PJ, Schaper WK, Jageneau AH. Analysis of the isovolumic pressure in the canine left ventricle. Pflugers Arch 1971; 329:9-22. [PMID: 5165160 DOI: 10.1007/bf00586897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|