ISA ABSTRACTS JACC Vol. 17. No. 2 February 1991: 188A

arch 5, 1991 ayed: 2:00PM-§:OO

OFTIMAL CONTROL OF MYOCARDIAL ISCHEMIA; IT OF COMBINATION THERAPY WlTH ATENOLOL AND NIFEDIPINE

esent: 2:00PM-3:OOP all F, West Concourse

Prevention uf Ischemia and/or Coronary Artery Disease Progression

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-1s M. Guy Stevm R. Bailey, Gerald W. DoKn, II. un.&ersilq7 of & Health 8ci& oerrter and VA Hospital, 8an Antonio, TX USA

cbmaryarterial~ia(QLE),def~asmsanilar orfusifom dilativof amajorepimwartery tht extmds the dumater of nomal adjaa segmmts or thii: patients largest cxmmary vessel by 153%, has been mported in 1 to 5% of ca~izations perfomed for atMro6clerctic conmazy armydiseaseoEkkhabdmiml

arrdCF~are&aracterizedhistiologi~ly destmctionofthemusculoelasticelements

elm of the tzulica u&.ia which is often

oQaaslmref* syndmms of artxrioadq-

c&wt 14 (19.7%) had significant CAE. !Nelve had IzifA ec- la& (man a--SD = 6.221 mm) and 2 had LAD ectasia (maan diame~~ = 8.0 mn). Clinical characteristics of the patient gn2q.s were:

aa (n=l4) CM=571 61.853.5 65.125.3

shamsis (%) 86 80 (%I 21 59

60.7221.1 56.3219.3 ion (3) 55 59

ofthe14cFApati&q7hadsqme&tl wall motion &fectsinthedistr&utionoftheectaticartezzy, linthe akenoeof a signi~:'czmtstmmsis. Wea~81&&2thatthat CAE is associated k+,~ abdominal aortic amuysym and my bepathogeneticallylinkedtmsystemicarmqmalMsailar disease.

I&man E I- Tam imi, Graham Davies, Agha W. Haider, Attilio Maseri, Cardiovascular Unit, Hammersmith Hospital, London, UK.

The effects of atenolol (A) 50 mg, slow release nifedipine (N) 20 mg, and their combination(AN) given 12 hourly, on myocardial ischemia were studied in 23 patients with stable angina pectoris, documented core- nary artery disease and a positive exercise test in a randomized, double blind, three way, cross over study. A treadmill exercise test and 24-hour ambulatory electrocardiogra@ic monitoring were obtained after a period of 5 days off-therapy (control) and at the end of 3 weeks of each treat- mart period. Compared to control, N induced an increase in resting heart rate of 14ti bpm (pcO.OOl), while A and AN rduck.3 ib by 24~2 and 2Oi1 bpm respectively @cO.OOl). The number of exercise tests rendered nega- tive after each intervention was 5,9, and 11 for N, A and AN respec- tively. Compared to control the time to onset 06 myocardial ischemia (1 mm ST-segment depression) during exercise significantly (pcO.001) in- creased compared to control by 3.2ti.6 min after N, by 4.6t0.4 min after A, and by 4.6t0.5 min after AN; Rate-pressure product (bpt mmHg) at I mm ST-segment depression increased by 2824970 (pcO.01) after N but full (pcO.001) by 4436t900 and 4SOk719 after A and AN respectively. The total ischemic time during ambulatory monitoring was reduced from 69a17 min during control to 37.54.8 min during N (pcO.01 vs control) to 1563.5 min during A (pcO.01 vs control and N) and to 6.53.7 min during AN (~~0.01 vs control and N, PcO.05 vs A).

EFFICACY OF THERAPY FOR T Michael H. Davidson, She Fletcher, Peter 0. Kwiterovich, H. Robert Superko, 1. Kent Smith, Norman R. Marquis, Jeffrey T. Whitmer, Gary D. Hutton, William S. Mullican, Clinical Research, Chicago, Illinois

Chicago Center for

Cholestyramine (Ql) and lovastatin (MEV) are effective LOL-cholesterol (LDL-C) lowering agents. The purpose of this study was to demonstrate the efficacy of these two agents when used in combination, Preliminary data from 133 hypercholesterolemic patients (mean age 56.8210.7

years) with LDL-C levels a160 mg/dl after six weeks treatment on 16gm/day QL and a low-cholesterol diet were randomized to five treatment groups. The daily dosages of each were: 1) continuation 16gm Ql; 2) 16gm Ql plus 2thng MEV; 3) 16gm Ql plus 40mg MEV; 4) 8gm QL plus 20mg MEV; and 5) 40mg MEV. Following eight weeks of treatment post-randomization, percent decreases in total cholesterol (%AC) and LDL-C (%AlDl-C) SEM were the following:

N %AC %AlDL-C 16gm Ql 27 17.6k2.2 16gm Ql + 20mg MEV

28.8k3.3

16gm Ql + 40mg MEV 22: 35. bl.6 50.9&l .8

8gm Ql + 38.1kl.7 55.1k1.8

35 40 mg MEV

20mg MEv 29.9A1.4 44.5k1.6 14 29.2*2.0 40.7k2.2

Fewer GI side effects and/or liver enzyme ?lpvations were. qoted in the 8gm Ql + 2Chng MEV group. These preliminary results indicate that the combination of lower doses of Ql and MEV result in marked lowering of total cholesterol and LDL-C without as many of the GI side effects and/or liver function abnormalities seen with higher doses of single or combination therapies.

Thus, the undesirable effect of high basal heart rate induced by N is neutralised by its combination with A. Whereas A and AN are equally efficacious in controlling exercise induced ischemia, AN was more effec- tive in reducing total ischemic burden.

ANTIANGINAL EFFICACY OF ANGIOTENSIN CONVERTING ENZYME INHIBITlON AND CALCIUM CHANNEL BLOCKADE AND THEIR COMBINATION IN CHRONIC STABLE ANGINA.

Hamid Ikram, Clive JS Low, Teresa M Shirlaw, Nardev S Khurmi, Ross Horsburgh, Ian G Crazier. Department of Cardiology, The Princess Margaret Hospital, Christchurch. New Zealand.

The role of converting enzyme inhibition in angina is controversial. We compared the effects of placebo (P). benazepril 1Omg bd (B), nifedipine retard 20 mg bd (N) and their combination (B+N) in a random order, case controlled trial of 34 patients with uncomplicated chronic stable angina. Each treatment phase was of two weeks duration and exercise testing was performed using a Bruce treadmill exercise protocol. N increased exercise time to lmm ST depression (4.2 f 0.3 10 5.0 _+ 0.3 min, P and N respectively. p ~0.05). B and B+ N had a lesser benefit (4.4 f 0.2 and 4.7 f 0.3 min. B and B+N respectively. NS). Sixteen of the 34 patients increased exercise time to Imm ST depression with B. These patients were identified by a higher 30 minute supine renin level (0.8 f 0.8 vs 0.4 +, 0.2 nmollllhr. PCO.05). No significant difference was observed in sublingual nitrate consumption or number of angina1 attacks between any of the treatments. Con;htsions, 1. Benazepril has a small effect in preventing exercise induced angina but is less effective than nifedipine. 2. The benefit of benazepril appears gre3tp.r in patients with higher resting renin levels. 3. A combination of benazepril and nifedipine appears to offer no advantage over nifedipine alone.