MARCO METRA. MD, MATILDE NARDI, MD. RAFFAELE GRJBBINI, MD: LIVIO DEI CAS, MD

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HEART FAILURE Effects of Short- and Long-Term Carvedilol Administration on Rest and Exercisr? Hemodynamic Variables, Exercise Capacity and Clinical conditions in Patients With Idiopathic Dilated Cardiomyopathy MARCO METRA. MD, MATILDE NARDI, MD. RAFFAELE GRJBBINI, MD: LIVIO DEI CAS, MD Activation of tbc sympahetic nervws qstcm is knmw IO be chmnic congave hean failure (I-7). l3ela~odm~ergic blockine aw~t~ beerwe of their abiliw IO inhibil rmrmathoadrene&-drive, an thcrefm potentiilly wdul fci tic lolyknn Bclrbbckrs wllh reddated vwdillla u&ily have rc- Irentmcn~ d this syndrome. Most studies of beta-bbcken in patients with hean failure cenlly ken inlmdwcd. Because dtwkad and prelod redw dun may OOUlllelset lb& Bboetcml lugaivc lnolmpic CfccI. have been performed with mctqwdol rhenpy. Lan@m~ ~hcsc dw seem pankulmrly nd2abk for the trcamwn~ of nwoprdol tbcrnpy has improved clinical dates and left wn- @cnk with heart failurn (7). Accordiiy, beta-blacken with vwdllawr raiviry, such as Iabclnbl (?Z). bwiwkdol(z3-28) cm when started at lmv dose& in 1 Id ad n&iwbl(z9), have been ~&II lo be well tdnated and of patients with heart laibuz (17.20). Clinical and hcnmrty. 8 imprwe clink4 status and Idi ventricular functim~ b namic &t4omdon after short-term mecpmlol admbds4m- @ents wbh cqenive heari fnilure. Cmwdild is a new beta-blocker devoid d inwinsie qmpalhamimcl activity.with aocintcd vasodiitw I&IS mdirkd by alpbal-reqbx amagmdsm (7,3%31). 11 has been well ~alcraled sbml tam (3.2) and hla imprwed symptoms, exenire lokrance nnd ler vm~rkulpr timcdon bngtmn (3.3) in patimk with bean failure caused by coronuy artery diswe. Hamw, thrrc shldirs were WI omrmlkd with placebo and m~lulted only patients with isclwmic hart disease in whom thefaw&deeuskofcarvediblmgbe relaicdtoawhution

in myomrdial iszbemia By mnhab+ patients with idiopathic dilated cardiom)opr&-y may be particu!arly se&ix to the benetkial ettezts of beta-b&en (2734). Pre1br.i~ repxts (3.5-Xt) have suggested that croveditol can improve sympmrm and tdt wntrkutar tin&n in p&tents whh idiisl.ic dilated cstiomyopathy. However. data regarding its short- and longterm e&e& on clinical symptoms ;mml rest and excrcisc hcmodymuoic variables are lacking. fn this stody we evaluated. u&g a raodomized doohleblind, placebosontmlled, parallel d&o. the ettects of short- sub&al and maximal exercix capacity and rest and evercbc hemodvnamic variables in a emoo of oartents with cangestive heah failure cased by id&&ii &ted cardiomvopathy trzated with digitalis. diuretic agems and angio&inmnvertiog cmymz inhiitors. hrmodynamic moeitoriog. Exercise was started at a work toad of 0 W, with further bwemenk of 20 W every 2 mio, at the wloeity of 50 rpm, up to the appearann oftbnitiog *apnea m fatigue. No patient had chest pain. major cmdiac arrhythmia or exercise-induced ST segment depression >I mm du@ the test. Elcctrowdiogmpbtc and rapimtmy variables were coo- Iinuously mwimred, hemodynamtc mes~lremcnt~ were obtaincd at rest. after an eqoilibmdon period of at least LO mb& doti@ thelast minutedeachwmktoadhaemea andatpeak exercise. MaGmaI cxercb capacity uas evaluated as peak exercise dumtion and VI+?eak Vo, vms cakulakd averaging the tinat 30 s of exercise. Before entry into the s&y, exercise tests were lrpated at 2- to 3.day immvals up to the acbiimcnt of rcpmduciblr results (peak Vc change benveen two cmwco. tiw texts rl ml& per mih). On a ditiercnt day, pattents also oodewcnt waloation of subma.im;ll exercise cam&. Tbii wax asxssed,as the dura- domtion. in cli~tally~stabdr condition. with & ch&c their dug rgimco to the-month before the study. AU p&cots bad symp(olllitk hean f&hue (New York Hcti?a.wcttioo functiomtclw.uarlll). Utventticolarejection fraction C3.54 by & excluded l$ endomyocamml t&y in pnticnis with il rmnpatibte clioicut hiiory. Patknrr with a history of ntcohd Owe, hypertmsiou @mar, vstvolar disease or other known uoscs of heart fatlum were also exctuded. WC ako cxclodcd patients wtlh major contmbutc&ns to hcl+hlocker therapy. &ch as bronchial asthma insulin-depndent diihctes mcllito.. &awed heart btoetc or bradvvrhvihminz Each wtient wx Ids or ha inhmoed written &scnt~befom entry in w the shy. All pattents were trcaed with dig& and tumscmids: all. except I in the cawdtiil gmu~ wcrc taktng ilngtotenrinamwttng eruyme iohibiton: 9 wrr also taking nitrates (kaswbjdc S-mononitrate. 40 mg three times B day. in all patcots); and 25 were t&tog snticongukmt apna Administration of olha kta.blockem. &tom notagonists, anttarrbyihmics and hypotenstve drugs (mxcludud d&tic drugs. m@enrin-fling emyme inhibitors and nirmtes) was not allowed. Pmcedwa On the day before the study, a triple-lumen %an-ciaaz catheter was inserted prcutaoeousty through the fight b~tcmal jogolu vein and positioned bt the pulmonmy arkry, and dn wterial cannula was ~itioo#i in the radial artery to mearac standard hemodynnmic rartabks. Cardiac nrpm was c&incd wia the thcrmcdtlution method, and derfwd hem&namtc vtiabtes were calculated according 10 standard formulas (39). Bic@c cxercisc testingwas perfomxd. in ti smmg pasitioo, with simulmoeous gas exchange and the b&&c ;n;utimal a-x& tadsring. This rwk load wai rcach& after a wnrming phase of 6 min at 20 W and was mdnuined up to exhaostioo or a maimurn of m min. The vacwork load was wd in the exxobmtion pcrfomwd heforc and sher loog-term therapy. LcR ventricular ejection fraction sod wlumes were notomndcldty dctcrmincd usingeqoil~tiiom radiomtclkk wntriculogmphy (JO). before and after long-term thxrapy. Clinical symptoms wro evaluated using functional classification and tk Minnesota Living nith Heart Failure (MLHF) qoestionnab-e (40. Rwcul. A do&k-bitt parsite randomized. placebommtrulkd dertgn was used with I:1 rrmdomhatkm to either oloc&~ or cxvcditot. lo the first port of the study. the short-term hcmodynamic cffcetx of plweboorcawedibl(12.5 mg, omlly)wcre cvnluotrd in hvo socce.&e days. 018 the first day. each patient underwent hcmodytumic monitoring at rest. in the supine position. with data collectrd before and I.?. 4, 6 and 8 h after drug odministntion. On the oat day, pattents wea evaluated ai rest sod during mazimal cnrdttlmmmy exercise telling before and 3 h after eitha placebo or carwdilol (125 mg orally) ingcstioo. A lttt meal was allowed hetwen the sixth and the eighth hour of study on the first day. To ensore hemodynamt atability, diuntic and vasodtlator agents were sdmiohtead onty at least 16 h before each hcmodynamic cvalu&lo. Aftcr compietkm of the short-term phase of the study, patients resumed their osoal dose of digitalis, diuretic drugs, angiotmninanwtfng enzyme iobibitors and nikates added to either placeha or carvcditol. Cavedilol was started at tbc da= of 6.R mg rwife daily with weekly ineremenk to the doses of 6.25 mg three times a day, 12.5 mg twioe a day, 12.5 mg thrcs times II day, and, last. 2.5 mg wiee a day. Five patienb weivzd ~25 mg wice a day of carveditol because bmdycmdia (rest hean rate CM heats/mio in three patiwib). hypoteoskm

(qstollc blood prcsx- <90 mm fig in one patient) or bwtddal wbaing (ate patient) was noted during the weekly vis6.s pufomud bdore cacb dose increment. After the titmlion pharc, paiena continued Lo rccefve tbe maximal dose 6x at lest 3 mauhs. Placebo was administered as tablets similar to catwdibf, using the tatne ptaml of drug admbdftion. Dhuctic dosage muld be adjusted a clhdcally indiated by the evaluation of n~ptoms and body weight dudng the hmg.term tleatmem phase. l?3ticnts WWT Kevalvated after at least 3 months of longlcrm theraw with tbr maximal dpaes ol either umdilol or cawedilol or &ebn and 3 h after thug readministration. Vasudiktor sad dhtretic agents mrc not administered during hcmodywmic mcaswemcnts n in the pwias 16 h. IXnical evaluation, pcd quilitim ndlonudide ve* tmaphy, wlmtarimal exercise testing and nsxsmenl of the MLHF score WCIC repeated hefore and aftt ~-term therapy.!3hmtlal mly#h Results arc apresed s man v* 2 SD. l-way amlyxii of viuiancc for m~tittuwr ~riablcs and mnthtgcilry tables lor categwic vatiabks wr4 wd to mmpsre be&line dmical data in the pllabo and catwdilol gmups and beeline data of the patients -ding and not rsspond- Ig to calvcdii ther@y. IWay and mpeated-meatttrcs Clinical f&ares of the patims randomized to receive nlacebz or umdilol were IIM imdscanllu dl6brcnt (Table 1 L fro patient ptwnkd untoward &cts U;t catsed irug will;. dmwal. I)uring the titmllon pha~ one patient taking catvcdilol pmscnled wonming mea that impmvcd with an iacre= in the hmsmdde b In Ihe lq-term tnamm phprc, IWO patient6 taking placebo and none kking mrwdild were admitted to hospital for wtscning heart failure, and fumsemlde daily dw was increased fmm 61 + 39 la 80 t 78mgiotheplrcbo~pandlrmn54~4toJ7~~ay in the mmdilrl gratp @ - NS). ulwtdrbolbtemanedibf~nlknattbcmmly. tumk nrponnr II s@tte rent, ShotI-temt adminimatim of urvedilol, 12.5 atg orally. induced. In compwiwn with pk. cebo, (I aignifwant t eductlon io test heart rate and tncan arterial and pubttcmaty wedge pressutes with 110 chanp in the other varkbles (Fii. 1). No ptient had advetse euccts or a dears XI% in cardiac index. was signllly reduced by both shoti- md loly-lcrm cave- dcuacd afta both shmt- and long-term amdilol admi& tratlca Peak cxctcls cardiac btdea dccresed sfta short-term catwdikl ingestion, but with m +ikmt innce r campared with bwlinc after long-tam thmpj. 12 h after lat dwg admlnhamtion Similar IO what was obsetwd at r&, stmkc wlvnnandstmkcwtkindnermrcnotcbo~dlysltortkfm arvcdilol ingestion andwuc f&niily impmvrd after long-term thcmpy. Rlghl atrial. mean @ttmttaty artctial and padnttntaty wedge prcssurex &clincd aftw slmrt-term dtug in#ia, with. hlttber dccreue alter Icaphmt thcnpy. Nlwlavuhr evlltulba, Left vmtricttk ejcctim fratim wan tan slgnilimnlly changed by long-temt placebo *l.tis Iration (fmtn 2C 2 6 to 19 + 5%) although it incrca& signbican~ fmm 20 f 7 Ia 30 * 12% (p < o.llmll) ala: bng-bzrm catwdilol adminktration: indivihul chaypr are shown in Fiim 3.l.A vnirktdar enddk5toiic vdume was not changed rigidscantly by ltnt6+rm camaim adminimalien(hrm160+4810153~46m~z~plaeeboudfrom 151+ 53 to 143 f 51 num* after caivcdild therapy).

.. bth hnctimml kiss and quality of iii, &s&d by the MUIF qoemimmaire, +dlicantly improved after long-term cawedibl umoistration compared with placebo (Fig. 5). AL!&lde ClmnSes iii MLHF sare mm not risracmuly mrre- patimtr were as&&d to two ~&IS. We defined as gdod Moonden oatients who had an increase >3 absolute units in lell vert&lar ejatlon fmciion and >180 s in submaximal exercise duration after long-term therapy. &SC wduep were chosen because they were X2 SD beyond the chan.se ocwve.d

2d+a3 2.3=03 23+&A 2.4taS 2sf6 29tll 2kt6 ltk 323 423 424 463 2226 2326 24Z6 23Z3 I,?6,636 16+6,626 in the placebo group. By these criteria, 14 @enis were pd reqtondwr, and 6 patimts vtae MI. No variable meunucd at basclbw and al re81 and peak aexcise diked s&dfim beiw.enthese IWO 6mupsexcqt ta1~c6ilol dose, which tended ta bc higher in the patients with a!korabje aspomc to therqy (p - 0.05) (TabJe 4).

Discussion and OR mnsismt with previous studies performed using S&Mum awedilol &dtdskatka and bclmdpamk beta-blockers with vasodikmr activity (23&W). In contrast, e&t& Guwdibl ingestion induced a signilicant redwtion in tb8 sbott-term athtdni8rt-dtica of metopmlol caused a r&cburc mk acd auaa at&j and ptdmo~ty wedge pref-surcs don in cardii index with no sigtdiicant change in left ventrio with M adwrse e&t4 on any bm&ytmmic vatkbk. Thcsz ular filling pleasrne (15,21,42,43), and, in some shtdics (21). an tatits aplain its good toktat4liq dutiug the titration phase increze in systemk vascularesistma.

ILMI. of the Ailing time tkmu$ hat rate rbwing (4S) (II better wntticuloattcrial cmtplhtg, or botk (4% Our study does not make it possibk to crtablkh the meehaninm by which short-lerm mwedibl dwtwed pllmo. nary wed& p~~run. fhk c&t might b! ml&d to its alpha,-antagonist anivity becaw peripheral vsndibtion may deercam pulmonary W.-&C pressure both thmq# a reduubn of prcload and. indirectly, tkmugh I rcdttctbn of mitral d. patients with d&d cardiomy&thy, the prcvalmcc of mitral regurgitation h high (44X and dcpmdencc of relax&n on left ventricular prewrc and sftedoad is enhanced (45). Corcomitant mechanisms may be represented by prolongation ular ftmctioli. both at rest nd hiring maximal &ercisc, witk a significant increase in cardiac stmkc volume and stroke wotk indarn accompanied by a tzdwtbn in t@ht and left vettttb ular dllbg fwewrcr. durinp aucise in only a few studies (24,46,47\ et al. (44.47) found mt innrarc In peak eamzim cm-dku, amkc volttmc and stmke work in&m aret k%?l_twnt metqmbl therapy. fimwwr, their rcsttlts UC Mimic to compare vdth otm because meauwtncttts mtx atfomrd at a fixed utb mwimsl wk bad. and tkc lest d&g w withkeld 24 h t&we each cvsluatbn in their studii (46,47). Out results an aimiku to thmc of Polkxk et al. (24). wlm evaluated peak act& F@n 3, lndividwl cllangg In left wtttbdar cjztion fmtinn (LV EF) after lung4em treatment whh ptaccbo (qm rbrkr [kft), and rynduol (satu ctrdm [Ii&q).

been widely descrfbed (48-50). and it seems unlikely that hem-blockerr can prevent it (51). An ndditiomd mechwirm of action of mwcdilol might be the reduction of mitral regurgimtiw hovwcr. Doppler ecboeardiigmp::ly was nm regularly pcrfurmed in our patients. WC alw tested the elkcts uf awdilvl madminiwmion after long-term therapy. Cmwdilol madministmtioo both at rest and at pea exwci.w produced u furtbcr reduction in heart mtc with a comequent decline in cm&c index Tbex dntu are wnsistent with recent results obtained using mespmlul(52) and show that tbw agents maintain their beta-blucking activily in heart failure wen lur km@m therapy. Unlike what nib obwwd aher short-term drug ;Idmkdktmtiun. ret pulmunx) pwsuws were nut changed, and s}stcmic vascular rcs~tmux fended to increase. taller the nrxt cmwdilol dose. Tbw rccults arc mnriam~t with the dev&pmcm of tolmance fu the wsudilstm ulphu,-untagonist activity of thiv drug. Ctbdwl syap~oms and amrise capr&y. In OUT study. derpitc the signilic~nt impmwncm in krvcntricukufunction. cxvcdilol theraw did nut signilicmuly change pak rwcise mpacity. musrurcd as peak cwcisr dumtion and peak Vu:. Ecra~sc thcx vmiablcs are hiibly rclatcj w the peak exmrise cardiac il?dex (S346). their lack of cbunge is likely caused by the mnwmi~ant mductkm in pak cxcrcise heart mte. Accordingly. pwk cxcrcisc capacity did nut cbangc in studiis in which bct;l-hlwkea decreased peak excxcisc bawl mtc (lb.lj.27-29). wlwx it improwd when peak heart rate w& not reduced (11.46). A diren wrmlation between the change in peak cwcisc hart rate and the chnngc in peak cwcix duration after bucindalal thimpy bus hen described (26). The incmuse bemwjynamic vmirablcs befun mul after lung-term bucindtdol Lempy. Our raulls du nui make il pumiile to dmw wnclunionr rcgatding the mechanism uf action of cmwdilol bx~usc we did not amess v&bks independent of luadii conditkmr Hwcvcr. an improvement in myawdial furwtion seems likely because the left venniculnr 6mctbm cuwc was shifted upwrrd and to the I& mui ejection fraction impmad with nu signilkant change in left vmwicular end-diawlic vulume md only I sliiht reductkm in ryrtemic wculttr rcristance ufter bx+term carwdilol therapy. Momover. rupid developmum of tokmocc to the vasodilatw bets of rlpha,-antagonists bar beaus un$b&nts with cortmmy artmy d&w were studied. A highly rignidmnt mcrem~nt m submaximal exercim dumtiun ws found ler long-term muvedilol thcmpy. This result is consistem with the impmvcmcnt in ktl ventrfcular function uhtuiwd with thisdrugund with the hypoth& lhot bluntinguf peak exerck~ hem? fatewar the main mcchunism of the lack of imprwrmcnt of peak exeti tokmncc. Simikw rcwlts were fmmd in another report (26). The improvement in rubmaimal crcrck t~lcrxnce was ilcmmprnied by md correlated with an impruwmcnt in qwlity of life. measured as Ihe MLHF smrr Predtction dtk re~paee to tbenpy. Similar to what was obrcwcd with other drugs. the mspon?e to ktabkxker tbcrspy is nut humogcncous in patientswith heart failure. Etkdugy hud u ri~nificunt mk in sumc stud& (27). and we evulwted mdy p;rtientr with idiiprdhic dilated cardiomyopathy to avoid the intlucvm of this vmiabk. In uur study, no baseline vminbk wil* ~mdiitivc of the mspansc to thcmpy. Tbeae rcmd~ ore in uccuxkmce with previous studies (9.13) but ditter from others in which a high I& heart mtc ad mom adw~~i left wmri~lttr dy,tipctkm wre bund to bc reinted with u fnwmble raps IO betahkxkadr (I I). Cm,dusfm~s. Ourntudy~uws that shoti-term therapy with the ka.bluckcr and vasodilatur cmwdilul tiwcs a reduction

in hcut rate and mean amid and MI wnlrkulu Rlling pm with no signifiml change In lhc Uha bemodynamicwiablc.s,md thm kmg4ermthmapysbmwa~lgniik~t improvement in.%mke vobune and rlmkc work indrn and kf~ vemriculu cjatica fmmlon, with I finthcr nductbn in bcmi rate and dgbt atrial and pulm~lmy wc@c pnmnres l helhcahemcdpmkcban~eaareprcmntboihmntiand dluing mnximal exmck. Peek crerck capacity is not sipi& audly akcted by either short- or kmg-lmm wvedikd admin. Ymdon, wiwer a al@ieati impwnem in clinical spnp IOK., quality d life and rubmaximll eaenise duntbn VP &k&d afler lon@xm tbcmpy. No bamlinc vtiabka prmit pwjiin of the rspnle to therapy.

JACC Vd. 24. Fir. 7 lwmm 1F34mo-17