This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by FALSETTI, H. L. Articles by BUNNELL, I. L. Search for Related Content PubMed PubMed Citation Articles by FALSETTI, H. L. Articles by BUNNELL, I. L.

(Circulation. 1971;43:467.)
© 1971 American Heart Association, Inc.

---

V_max as an Index of Contractile State in Man

HERMAN L. FALSETTI M.D.¹; ROBERT E. MATES PH.D.¹; DAVID G. GREENE M.D.¹; IVAN L. BUNNELL M.D.¹

¹ From the Departments of Medicine and Mechanical Engineering, State University of New York at Buffalo, Buffalo, New York.

The maximal, no-load, velocity for the contractile element (V_max) was estimated in 45 patients. The patients included: 17 with normal left ventricular dynamics; eight with volume overload, compensated; 11 with volume overload, decompensated; three with pressure overload; and six with cardiomyopathy. Contractile element velocity (V_CE) during isovolumic contraction was estimated in two ways: (1) from left ventricular pressure data alone, where V_CE=(1/28.8p) (dp/dt), and (2) pressure data combined with measurement of left ventricular geometry (right anterior oblique cine). V_max obtained in these two ways agreed well for most patients (r = 0.82). In the normal patients, V_max varied from 1.46 to 2.64 muscle lengths per sec; in contrast that of the patients with cardiomyopathy varied between 0.71 and 1.34 muscle lengths per sec.

Other indices of contractility (ejection fraction, peak dp/dt, peak velocity of circumferential fiber [peak V_CF], peak V_CE, and V_CE at zero stress) were compared on the basis of statistical correlation and consistency of other clinical evidence (presence or absence of congestive failure). Good correlation was obtained between V_max and peak V_SE (r = 0.68). Ejection fraction and peak V_CF were less sensitive. Neither the peak rate of pressure rise or V_CE at peak stress show any significant correlation with V_max or clinical state. Previous studies have shown that V_max can be evaluated from pressure data alone; this study confirms this finding in patients with mitral regurgitation as well as in those with normal outflow impedance.

Key Words: Contractile element • Cardiac muscle mechanics • Left ventricular wall stress • One-plane cineangiography

Submitted on August 12, 1970
Accepted on November 30, 1970

This article has been cited by other articles:

				S. S. Ahmed and T. J. Regan Are Pressure-Volume Relations at End-Systole a Reflection of Left Ventricular Myocardial Contractility? Angiology, February 1, 1983; 34(2): 137 - 148. [Abstract] [PDF]