Quantitative Determination of Regional Left Ventricular Wall Dynamics by Roentgen Videometry

Transcription

1 Quantitative Determination of Regional Left Ventriular Wall Dynamis by Roentgen Videometry By JEAN G. DumESNIL, M. D., ERIK L. RITMAN, MB., PH. D., ROBERT L. FRYE, M.D., GERALD T. GAU, M. D., BARRY D. RUTHERFORD, M.D., AND GEORGE D. DAVIS, M.D. Downloaded from by guest on July 12, 218 SUMMARY The use of roentgen videometry as a means of studying regional left ventriular wall dynamis and performane was evaluated in 32 patients undergoing oronary arteriography. Nine patients had normal oronary arteriograms and hemodynami findings (group 1), 8 patients had generalized derease in left ventriular ontration and abnormal hemodynami findings (group 2), and 15 patients with oronary artery disease had regional wall dynamis abnormalities (group 3). Sixty-per-seond determinations of wall thikness were performed in seleted sites of the left ventrile. Measurements performed inluded end-diastoli wall thikness (EDTw), mean and peak rates of systoli wall thikening (mfi and p dtw/dt), and frational systoli inrease in wall thikness (ATw/EDTw). In patients with uniformly performing ventriles (groups 1 and 2), these parameters orrelated well with other parameters of ventriular funtion. Best distintion between the "inormal" group (group 1) and the "abnormal" group (group 2) was ahieved when the rates of thikening (um and p dtw/dt) were utilized (P <.1). In patients of group 3, three types of abnormal regional wall dynamis ould be determined and quantified objetively: hypokinesia (dereased p dtw/dt), akinesia (p dtw/dt = ), and dyskinesia (p dtw/dt < ). The severity of the abnormality of the wall dynamis orrelated well with the presene or absene of a previous infartion on the eletroardiogram, and the anatomi loation was strongly orrelated with the distribution and severity of oronary artery lesions within a given ventrile. Additional Indexing Words: Wall thikness Eletroardiogram Regional ventriular performane THE IMPORTANCE of abnormal regional myoardial performane as a ause of ventriular dysfuntion has been emphasized by many observers.', 2 While measurements of left ventriular volumes and ejetion fration have been utilized in evaluating the performane of ventriles with normal or uniformly depressed funtions, these do not provide an adequate expression of regional dysfuntion nor loation nor extent of suh dysfuntion when the ventriles have regional myoardial disease, suh as ours with oronary artery disease.3'4 Reent attempts at evaluating differenes in regional myoardial performane have inluded out- From the Mayo Clini and Mayo Foundation, Rohester, Minnesota. Supported in part by Researh Grants HL-14196F, RR-7, and HL-4664 from the National Institutes of Health. Dr. Dumesnil was a fellow of the Medial Researh Counil of Canada at the time this study was done. Address for reprints: Dr. E. L. Ritman, Department of Physiology, Mayo Clini, Rohester, Minnesota Reeived November 8, 1973; revision aepted for publiation May 28, Coronary artery disease lining of ventriular ontours,5 estimates of regional hanges in ventriular diameters,6 use of epiardial markers,7 8 radarkymography,9 and ehoardiography.' In partiular, Eber et al." found that the extent of wall thikening in diseased portions of the left ventrile was markedly redued. To date, however, a routine, objetive evaluation of regional myoardial performane in both relative and absolute terms has not been feasible, most methods proposed being either qualitative only or too time onsuming for frequent measurements during the ardia yle. The present study was designed to evaluate regional left ventriular wall dynamis by means of roentgen videometry. Methods Left ventriular angiograms from 32 patients undergoing oronary arteriography were analyzed. The linial and laboratory data of these 32 patients are listed in table 1. Cardia atheterization was performed with the patient in the fasting state after the intramusular administration of 1 mg of sodium pentobarbital. Left heart atheterization, left ventriulography, and oronary arteriography were performed by the Sones tehnique. 12 In three patients, Cirulation, Volume 5, Otober 1974

2 ROENTGEN VIDEOMETRY 71 Downloaded from by guest on July 12, 218 Figure 1 A) Right anterior oblique and left anterior oblique projetions of biplane left ventriular angiogram reorded as a single split-image on video tape. Bright spots are videometri reognition points of endoardial and epiardial borders. B) Postero-lateral wall as seen in left anterior oblique projetion. Positioning of horizontal brightened lines determines upper and lower limits of wall segment intended for analysis. The video image ontrast has been adjusted at the time of analysis to provide maximal signal-to-noise rutio of the epiardial and endoardial outlines for optimal border reognition. This adjustment is ritial for reliable analysis and must be performed for eah seleted region. (paifiation of the left ventrile adequate for wall thikness studies was obtained after the injetion of the ontrast material into the main pulmonary artery, Left ventriular injetions were performed before oronary arteriography by utilizing a no. 7 or 8 NIH atheter attahed to a three-way stopok system. The patient was plaed in the right anterior oblique position. While the patient was in deep inspiration, 5 ml of ontrast material (76% Renografin) were injeted ontinuously with the use of a power syringe during a 3- to 4seond period. A biplane video image-intensifier system (9inh GE fluoroon, 3), with speial eletroni modifiations for enhaned fluorosopy, was used.'3 At ventriulography, the kilovoltage of the X-ray generator was held stable, and the milliamperage was inreased by four to six times the normal fluorosopi dose and held stable in order to obtain optimal signal-to-noise harateristis at Cirulaoion, Volume 5, Otober 1974 angiography. The biplane video images were reorded as a single split-image (fig. 1) on 2-inh video tape at the rate of 6 video fields per seond.'4 On ompletion of ontrast material injetion, left ventriular pressure traings were obtained by use of the three-way stopok system, although in patients with pulmonary artery injetion, pressure traings were available ontinuously throughout ventriulography. During the angiography, up to seven hannels of data, inluding the eletroardiogram, low- and high-sensitivity left ventriular pressure, and brahial arterial pressures were reorded on the same video tape at the rate of 1, samples/se by means of a speially developed video pulseheight modulator system." The ventriular angiograms were analyzed with the use of an operator interative border-reognition system interfaed with a omputer (CDC 35) as desribed previously. 4 The bright spots in figure 1 represent the endoardial and epiar-

3 Downloaded from by guest on July 12, 218 7I2 dial reognition points and are transmitted to the omputer as digital values of their relative positions. Calibrations were obtained from biplane video images of an objet of known dimensions reorded on the same system under similar X-ray magnifiation onditions. Eah video field was analyzed so that 6/se determinations of left ventriular shape and wall thikness were possible. Notably, even with aurate loalization of the epiardial and endoardial borders in the angiogram, the shortest distane between these borders is not neessarily the true wall thikness at that point.'6 Thus, we have used the term "wall dynamis" rather than "dynami wall thikness," but for onveniene, wall thikness is at times used in the manusript. The eletroardiographi and pressure values orresponding to eah field were omputed simultaneously. Left ventriular volumes were alulated by a omputer program based on Simpson's rule.17 Left ventriular wall thikness was determined in sites seleted by the operator and where border reognition of the epiardium was desirable and optimal. As illustrated in figure 1, the position of the horizontal bright lines determined the upper and lower limits of the wall segments being used for thikness determinations. Wall thikness was omputed as the least distane between the endoardium and the epiardium and averaged out for the partiular wall setion being studied. Depending on the dimensions of the ardia silhouette and on the extent over whih the epiardium an satisfatorily be identified, one to three setions of the anterior wall and one to two setions of the postero-lateral wall were generally studied. Plots of the 6/se determinations of wall thikness were then displayed along with the eletroardiogram and, if so desired, the orresponding pressure values. Diastoli wall thikness, frational inrease in wall thikness, and mean and peak rates of wall thikening (dtw/dt in m/se) were then alulated. Multiple determinations of wall thikness in different regions of the same ventrile permitted omparison of yli thikness values omputed during the same beat. Validation of Methods The auray and reliability of the videometri tehniques have been previously established."8 When the omputer program for thikness determination was used for an objet of known dimensions, under the same X-ray magnifiation onditions, values obtained were within 1 % of predited values. Under onstant beat-to-beat onditions (sinus rhythm and unhanged end-diastoli volume), mean and peak dtw/dt were reproduible in 11 patients within 8.5% and 1%, respetively. Furthermore, when the analysis of one ventriular segment was repeated at different times using renewed operator settings, values were reproduible to within 1 %. Results During a three month period, from November 1972 to January 1973, the angiograms of 32 patients were studied. Two riteria were used for patient seletion: (1) satisfatory identifiation of the epiardium and endoardium on the angiogram and (2) the possibility of inluding the patient into one of three groups. Group 1 patients had normal left ventriular funtion and pattern of ontration as determined by visual inspetion of the ventriulogram; group 2 patients had DUMESNIL ET AL. generalized derease in left ventrile performane and generalized derease in vigor of ontration by visual inspetion of the ventriulogram; and group 3 patients had more than 75% narrowing of the left anterior desending, irumflex, or marginal branhes of the oronary arteries delineated by oronary arteriography and (in some patients) evidene of abnormal regional left ventriular wall motion on visual inspetion of the left ventrile angiogram. The study was designed to permit assessment of the quantitative rather than the qualitative regional ventriular funtion. Data from groups 1 and 2 were used to establish a relationship between wall dynamis and the funtional status of uniformly performing ventriles as defined by onventional parameters. Criteria derived from this relationship were then used for the study of ventriles with regional abnormalities of ontration (group 3). Group 1, Normal Ventriles (Table 1) The first group onsisted of nine patients who had normal findings on oronary arteriograms and normal hemodynamis (left ventriular end-diastoli pressure less than 16 mm Hg, ejetion fration above 55%, and no regional dyssynergy on visual inspetion). A typial omputer-generated plot of 6/se left ventriular wall thikness determination is shown in figure 2. In most ases, four distint phases were identified during one ardia yle: A, a transient presystoli "dip," presumably the result of atrial ontration; B, a phase of rapid thikening during ventriular ontration; C, a phase of rapid thinning orresponding to relaxation and rapid diastoli filling; and D, a phase of slow diastoli thinning orresponding to slow diastoli filling. The end-diastoli wall thikness averaged 1.16 m (range,.51 to 1.82 m), and the mean perentage inrease in wall thikness was 82% (range, 46 to 156%). Peak rate of wall thikening (peak dtw/dt) averaged 7 m/se (range, 4.96 to 9.8 m/se), and mean rate of wall thikening was 3.99 m/se (range, 3.6 to 5.32 m/se). These values were obtained during regular beats in all patients. In six patients, postextrasystoli yles also were present during ventriulography. Individual wall thikness values for postetopi yles are listed in table 2. In all instanes, the wall thikness at end-diastole was less than that observed preeding regular yles, and the values of perentage inrease in wall thikness and of mean and peak rates of wall thikening were markedly inreased when ompared to the values obtained during the regular yles. Three patients (ases 1, 3, and 8) in this group had two or more different sites in the same ventrile whih ould be studied, as indiated in table 1. The maximal differene in peak dtw/dt between different sites was.31 m/se or 5.6% of the least Cirulation, Volume 5, Otober 1974

4 Downloaded from by guest on July 12, 218 ROENTGEN VIDEOMETRY value. Additional observations in normal patients may well indiate a wider range of values for rates of wall thikening in different areas of the ventrile, but thus far no onsistent pattern of variation has been noted. Group 2, Derease in Left Ventriular Funtion (Table 1) This group was omposed of eight patients with generalized derease in left ventriular funtion. Two patients had idiopathi ongestive ardiomyopathy with normal oronary arteriograms. The remaining six patients had severe involvement of the three major oronary vessels and generalized redution in left ventriular wall motion on onventional visual inspetion. In this group, peak dtw/dt averaged 2.68 m/se (range, 1.7 to 4.39 m/se), and mean dtw/dt averaged 1.67 m/se (range,.8 to 2.95 m/se). All determinations were performed during regular yles. Both peak and mean rates of wall thikening were signifiantly less than values obtained in patients of the normal group (P <.1, fig. 3). Although values of perentage of wall thikening in the two groups differed signifiantly (P <.2), onsiderable overlap of the distribution of values was present. End-diastoli wall thikness had a tendeny to be less in this group, but it did not differ statistially from that of the normal group. Group 3, Regional Wall Dynamis Abnormalities (Table 1) The third group onsisted of 15 patients with more than 75% narrowing of the left anterior desending, irumflex, or marginal branhes on oronary arteriography. This group was further subdivided on the basis of the videometri data analysis into three -- 'z: MALE 53year E C G-..o~ ~ 2.5 A B CEC A BC Seonds Figure 2 Computer-generated plot of yli wall-thikness hanges as measured from a left ventriular angiogram in patient with normal left ventrile. A, atrial ontration; B, ventriular ontration; C, relaxation and rapid diastoli filling; D, slow diastoli filling; E, etopi beat. Cirulation, Volume 5, Otober 1974 subgroups: (a) regional derease in the rate of wall thikening (hypokinesia); (b) no yli hange in wall thikness (akinesia); and () regional systoli wall thinning (dyskinesia).* The sites where wall thikness measurements were performed are identified in table 1. Only the representative values are inluded in table 1, and in instanes in whih determinations from two regions within the same ventrile are similar and within normal range, only one region is mentioned. Hypokinesia A typial omputer-generated plot of measurements of regional wall thikness in a ventrile (ase 2) illustrating regional hypokinesis is shown in figure 4. The extent and rate of thikening of the low anterior wall were markedly dereased when ompared to the high anterior wall. This patient had an 8% narrowing of his left anterior desending oronary artery immediately proximal to the origin of its diagonal branh. A omparison of the mean and peak dtw/dt observed in the anterior and postero-lateral portions of a ventrile with regional hypokinesia is shown in figure 5. Anatomi sites of oronary artery narrowings are identified. All six patients with narrowing of 75% or greater (grade 3 or 4) of the left anterior desending oronary artery had relative hypokinesia of the *These definitions of wall thikening abnormalities must not be onfused with definitions of wall motion abnormalities as measured by movement of the endoardium alone. THICKNESS Normal LV Disease _ 2' 5 _- _1 3 - m MEAN d Tw d t (m /se) p<.ooi Normal Figure 3 8 C9. LV Disease PEAK dtw dt (m /se) p<.ooi a Normal 7()3 LV Diseose Left) Frational inrease in wall thikness expressed as a perentage of end-diastoli wall thikness in patients with normal left ventriular funtion and in patients with generalized derease in left ventriular performane. Right) Mean and peak rates of wall thikening (mean and peak dtw/dt expressed in m/se) in same two groups of patients. Peak dtw/dt values provided the most onsistent disrimination between the two groups of patients. 8

5 ,4 ++ P o CS p--o Z~~O~~ - {,- -4o In,v M lf. 1 s C -D d / O es;i ~ C =. C~i6 o _ s - o o- tc- to e d O + ~s DUMESNIL ET AL. N o O o me * ** *~ ktt Lo _s snso zo CS- o s + ocs --tlq O~~ dc ~ ~~~C 4Os< es t~- 1. t.. 66o6o m es Cie1 1 oi t n < ot ~~fd Downloaded from by guest on July 12, t.E ki ;wi G) *.r~ 35 5 C e Q ++ Q 1.1. g! ab P.. VC. V "- P- C CD m <t O "1 In _ - o o _ m tr- ~ C o - - O= O LO 1- :C: t~- to bx~~ ~~ - m 1-1,4O P-4 "- O C q CM ~- --- C -4 - X g 9V Z.tV C...~ 9V V,' V! VC 4~~~~~~ -a ~~ 3 t t - 3t-.b +4 n - 1s to IC, 1 d +: t t o N q N m "+ *4 ^ Q oo jo q : 1 << C t r 3 2 z Z; Z W; z z z z z o >~~~~~~~~~~~~~~~~~~~O V ) o t to o.. ) a r -M ~ to ItO o 'V _ 1-.':sp pp Cs C: a) ts t- eq Cirulation, Volume 5, Otober 1974

6 ROENTGEN VIDEOMETRY 75 C4. 1 M t- t' me ) " X X to. ts " o t- in Le -oox X m q ", ~ -* C. t. -..~ 1..~.6.l.~.1.6.C _..6 C "..In ---d to P b O O N CD O C= C d - O1- CD o TV -t N,!! C 4t4i3 = m X X m 'C, t [ I-.i M M Mt. it ". -o. C - - to t- 's. C OC t C o - 4 C= X C MO tl_o - CM _;i 1. -~ -, N eci In - ~ -d "- '-~ to 1 C1 1 t- m 1- CIA m - O CS O Cn CS C6 CS 1 -b1 Co Lto oc4m mt Xt In :=Q < 5C,: = "m = toc s o-tso to X Cn C O to g _ : 3 Downloaded from by guest on July 12, 218 _s G to e CS - 1 dq q._ - ~ -~ to. O to_ to C) " "CD C) "L to.... CSl eq O to CSJ C t. _o 4 v - _O - - CD -I tso - oo - / o D s z to CC r to- t~ C). * C).o " 3 3 m O 1 CI Wo 7 m q to- o- -- e *O *o. l * : t.. -t.. > - CI- - Oo Cq C) t OC) 3z ;._ 4:7 B 1 o - d d - ) 2,i._ S " Q.. " C; -. >- H C Q -e 3 X.E 1. ':H e -_ C) C) zs D z to. I" m~~ a) - *o p o- QE ri -> Q E-, o -_.r4 C t- ;> d m 9 q l q N CI s 6! Cirulation, Volume 5, Otober 1974

7 76 DUMESNIL ET AL. Downloaded from by guest on July 12, 218 '3 l-k b ECGJ 2v- 1.-.I L 1.5 _ I.5 i'7 6* :.1 _; 1 1 Vew H igh Ant Wa I PI -4e Low Ant Wall i *wa - Table 2 Comparison of Left Ventriular Wall Dynamis in Six Patients With Regular and Postetopi Beats During Left Ventriular Angiography Parameter* Regular Postetopi EDTw (m) ATw/EDTw(%) Mean dtw/dt (m/se) Peak dtw/dt (m/se) *Averages: end-diastoli wall thikness (EDTw), frational inrease in wall thikness (ATw/EDTw), and mean and peak rates of wall thikening (mean and peak dtw/dt). I two remaining patients had signifiant narrowings of the left anterior desending and left irumflex or- Seonds onary arteries and exhibited hypokinesia of both the Figure 4 anterior and postero-lateral ventriular walls. Eleer-generated plots of simultaneous regional wall-thikness troardiographi evidene of a previous myoardial Comput hanges in a 62-year-old man with 85% narrowing in middle third infartion tended to be assoiated with lower values of of left 6anterior desending oronary artery. Extent and rate of peak and mean dtw/dt in orresponding hypokineti thikeniing were markedly dereased in area normally perfused by regions, when ompared with values obtained in this vess el. hypokineti regions of patients without evidene of prior infartion. Study of the postero-septal wall anteri( r left ventriular wall. Furthermore, thikness was not performed in the present study hypokilnesia was most severe toward the apex in beause the angiographi projetion used preluded patientts in whom two determinations in the anterior adequate delineation of the epiardial surfae. wall were feasible. In three patients with narrowing of the left irumflex oronary artery of 75% or greater, values of mean and peak dtw/dt reorded for the postero-lateral wall were signifiantly lower than values reorded in other regions of the ventrile. The Peak - dtw/dt (m/se) Akinesia The one patient in this group had a omplete olusion of his left anterior desending oronary artery and eletroardiographi signs of a previous Mean - dtw/dt (m/se) 3: Postero- Lateral WaOl l Figure 5 Comparison of mean and peak dtw/dt values in two different ventriular regions of 11 patients with oronary artery disease and regional hypokinesia and 2 patients without oronary artery disease. o, patients with 75% or greater narrowing of left irumflex artery; A, 75 % or greater narrowing of left anterior desending artery;, 75 % or greater narrowing of both LAD and left irumflex arteries; dark symbols, ECG evidene of prior infartion; and A, in this ase, absissa represents high anterior wall values; x, no oronary arteriographi evidene of oronary narrowing. Cirulation, Volume 5, Otober 1974

8 Downloaded from by guest on July 12, 218 ROENTGEN VIDEOMETRY ECG 2.5 Mid Ant Wall -w.5l - _Post- Lot Wall o Seonds Figure 6 Simultaneous wall-thikness hanges in a 47-year-old man with total olusion of left irumflex oronary artery and ECG evidene of previous infero-posterior myoardial infartion. Postero-lateral wall shows paradoxial systoli thinning. anterior myoardial infartion. Values for wall thikness in the apial regions of his left ventrile were onstant and showed no systoli or diastoli variation. Dyskinesia Three patients had regional left ventriular wall thinning during systole (fig. 6). Systoli wall thinning is expressed as a negative value in table 1. Both patients with left ventriular apial wall thinning had omplete olusion of the left anterior desending oronary artery and eletroardiographi evidene of an old anterior sar. The patient with systoli thinning of the postero-lateral wall had a omplete olusion of his left irumflex and right oronary arteries and eletroardiographi evidene of an infero-posterior myoardial infartion. Disussion Mithell et al.19 suggested that hanges in wall thikness were strongly influened by the Frank- Starling mehanism and hanges in the ontratile state. With end-diastoli ventriular volume and wall thikness held onstant, the systoli inrease in wall thikness was 42% during a ontrol period and 62% after infusion of norepinephrine. The same authors also found that the extent of wall thikening when using diret measurement (25 to 45%) was onsiderably less than that found by angiographi tehniques (8 to 12%). This latter result agreed with the perentage inrease in wall thikness found in human subjets by other investigators,2 and the disrepany between the two methods was attributed to the behavior of the Cirulation, Volume 5, Otober trabeulae arnae during systole. Gault et al.21 related hanges in wall thikness to left ventriular disease and, using a diret measurement tehnique, found a perentage inrease in wall thikness of 32% in patients without and 23% in patients with left ventriular disease. Eber et al.,1" in a study of two patients with oronary artery disease, observed that regions of normal and diseased myoardium in the same ventrile ould be differentiated by analysis of hanges in the left ventriular wall thikness. Our study utilized rates of wall thikening rather than the perentage inrease in wall thikness for the purpose of evaluating regional left ventriular wall dynamis. As evidened in figure 3, a more distint differentiation between patients without and with left ventriular disease was ahieved with the use of this riterion. The parameters that we used also orrelated well with the anatomi loation of signifiant oronary artery lesions and with the ventriular regions having abnormal dynamis. In all ases, lesions of the left anterior desending artery orresponded to anterior wall dynamis abnormalities, and lesions of the left irumflex orresponded to postero-lateral wall dynamis abnormalities. However, it is important to emphasize that the patients in whom abnormalities of left ventriular ontration were quantitated represent a seleted group. No impliation an be made from the urrent data that all patients with a given degree of narrowing in a oronary artery will have detetable hanges in rate of wall thikening in the area supplied by the diseased oronary artery. Studies are planned to evaluate the presene or absene of suh abnormalities in regional left ventriular ontration in relation to severity of oronary artery narrowing in an unseleted onseutive series of patients. This study also provided an objetive means of differentiation among three types of regional wall dynamis abnormalities: hypokinesia, akinesia, and dyskinesia. These data also orrelated well with eletroardiographi findings, akinesia and dyskinesia being found only in patients with prior myoardial infartion. In patients with regional hypokinesia, redution in regional wall dynamis had a tendeny to be most severe in those who had eletroardiographi evidene of a previous myoardial infartion. Values of end-diastoli ventriular wall thikness and perentage inrease in wall thikness for our group of normal patients were similar to those observed by previous investigators.'1 19, 2, 22 In ertain patients (ases 2, 21, 23, and 26, table 1) with regional wall dynamis abnormalities, peak dtw/dt in the regions supplied by a oronary artery with more than 75% stenosis was higher than in the normal group and suggests a ompensatory inreased funtion of these regions.

9 Downloaded from by guest on July 12, 218 (Os The inreased rate of wall thikening seen during postetopi beats is onsistent with the Frank-Starling mehanism'9 and extrasystoli augmentation of ontratility. It also illustrates the advantages of a apability to make analyses through several seleted ardia yles. The possibility that an extrasystole during the left ventriular injetion may provide an important intervention for evaluating left ventriular funtion is under investigation, as is the evaluation of other positive or negative inotropi influenes on rates of wall thikening. A method is desribed for the quantitation and objetive evaluation of regional wall dynamis. This method of study has several potential appliations, partiularly in the study of patients with oronary artery disease. The relationship between abnormal patterns of ontration (as depited by the ventriulogram) and the wall dynamis is not always lear or amenable to quantitation on visual inspetion beause of the rapidity of the events, the relatively small dimensional hanges involved, and the onurrent movement of the setion of wall under study. At present, this measurement an be interpreted as an empirial index of myoardial funtion as far as quantitative determination is onerned, but the measurement is onsidered to be a diret indiation of the regional loalization of myoardial dysfuntion. Aknowledgment We gratefully aknowledge the support and assistane of Mr. Ralph E. Sturm and Dr. Earl H. Wood in the development of the roentgen videometry system used in this study. Skilled omputer programming and patient data analysis were performed by Mr. Donald L. Cravath, and assistane in the ondut of these studies was given by Messrs. Gerald M. Alborn, Rihard Christopherson, James C. Fellows, and Ralph G. Goodrih, in addition to the members of the tehnial staff of the Cardia Laboratorv. Referenes 1. HE\I SN MV, HEIN LE RA, KLEIN MD, GORLIN R: Loalized disorders in myroardial ontration: Asynergy and its role in ongestive heart failure. N Engl J Med 277: 222, B XNILEY WA, JONES WB, DODGE HT: Left ventriular anatomial and funtional abnormalities in hroni postinfartion heart failure. Ann Intern Med 74: 499, VO(EL JH, RNISH D, MCFADDEN RB: Underestimation of ejetion fration with singleplane angiography in oronary artery diseases: Role of biplane angiography. Chest 64: 217, CHATTEBJEE K, S\XAN HJC, PARNMLEY WW, SLSTAITA H, M,Nxi( us H, MATLOEF J: Depression of left ventriular funtion due to aute myoardial ishemia and its reversal after aortooronary saphenous-vein bypass. N Engl J Med 286: 1119, FEIL l) BJ, RLSSELI RO JB, DO\\ LING. JT, RACKLEY CE. Regional DUMESNIL ET AL. left ventriular performane in the year following myoardial infartion. Cirulation 46: 679, KLEINM D, HERBIAN MV, GORLIN R: A hemodynami study of left ventriular aneurysm. Cirulation 35: 614, MDONALLD IG: The shape and movements of the human left ventrile during systole: A study by ineangiography and by ineradiography of epiardial markers. Am J Cardiol 26: 221, KON(- Y, MORRIS JJ JR, MCINTOSH HD: Assessment of regional myoardial performane from biplane oronary ineangiograms. Am J Cardiol 27: 529, K.zxxIAS TM, GANDER MP, Ross J JRi, BRALU\WAL) E Detetion of left-ventriular-wall motion disorders in oronary-artery disease by radarkymography. N Engi J Med 285: 63, FEIGENBALNI H: Ehoardiography. Philadelphia, Lea & Febiger, 1972, p EBER LM, GREENBERG. HM, OKE JM, GOBLIN R: Dynami hanges in left ventriular free wall thikness in the human heart. Cirulation 39: 455, SON-ES FM JR, SHIREY EK: Cine oronary arteriography. Mod Conepts Cardiovas Dis 31: 735, RITMI AN EL, ST lrni RE, WOOD EH: Biplane roentgen videometri system for dynami (6/se) studies of the shape and size of irulatory strutures, partiularly the left ventrile. Am J Cardiol 32: 18, RITIANI.\ EL, SIruR-I RE, WooI) EH: A biplane roentgen videometry system for dynami (6/seond) studies of the shape and size of irulatory strutures, partiularly the left ventrile. In Roentgen-, Cine- and Videodensitometry: Fundamentals and Appliations for Blood Flow and Heart Volume Determination, edited by HEINTZEN PH. Stuttgart, Georg Thieme Verlag, 1971, p S-iLRMl RE, RITNIAN EL, HANSEN RJ, WOOD EH: Reording of multihannel analog data and video images on the same video tape or dis. J Appl Physiol 36: 761, WOOD EH, RITMAN.. EL, STURNi RE, JOHNSON S, SPIVAK P, Gil BEBl BK, SMITH HC: The problem of determination of the roentgen density, dimensions and shape of homogeneous objets from biplane roentgenographi data with partiular referene to angioardiography. In Proeedings of the San Diego Biomedial Symposium, vol 11, 1972, p CHAP\IAN CB, BAKER, MITCHELL JH, LLIER RG: Experienes with a inefluorographi method for measuring ventriular volume. Am J Cardiol 18: 25, Rn SN EL, STRNXI RE, WOOo EH: Comparison of volume of anine left ventriular asts and angiograms using biplane and monoplane roentgen videometry. (abstr) Physiologist 13: 294, MITCFHLL JH, WILDEN I HAL K, MULLINS CB: Geometrial studies of the left ventrile utilizing biplane inefluorography. Fed Pro 28: 1334, HooD WP JR, RAIIKLEY CE, ROLETT EL: Wall stress in the normal and hypertrophied human left ventrile. Am J Cardiol 22: 55, GLULT JH, Ross J JB, BBAUL\N\ALD E: Contratile state of the left ventrile in man: Instantaneous tension-veloity-length relations in patients with and wvithout disease of the left ventriular myoardium. Cir Res 22: 451, SANDLER H, DoDGE HT: Left ventriular tension and stress in man. Cir Res 13: 91, 1963 Cirulation, Volume 5, Otober 1974

10 Quantitative Determination of Regional Left Ventriular Wall Dynamis by Roentgen Videometry JEAN G. DUMESNIL, ERIK L. RITMAN, ROBERT L. FRYE, GERALD T. GAU, BARRY D. RUTHERFORD and GEORGE D. DAVIS Downloaded from by guest on July 12, 218 Cirulation. 1974;5:7-78 doi: /1.CIR Cirulation is published by the Amerian Heart Assoiation, 7272 Greenville Avenue, Dallas, TX Copyright 1974 Amerian Heart Assoiation, In. All rights reserved. Print ISSN: Online ISSN: The online version of this artile, along with updated information and servies, is loated on the World Wide Web at: Permissions: Requests for permissions to reprodue figures, tables, or portions of artiles originally published in Cirulation an be obtained via RightsLink, a servie of the Copyright Clearane Center, not the Editorial Offie. One the online version of the published artile for whih permission is being requested is loated, lik Request Permissions in the middle olumn of the Web page under Servies. Further information about this proess is available in the Permissions and Rights Question and Answer doument. Reprints: Information about reprints an be found online at: Subsriptions: Information about subsribing to Cirulation is online at: