ABSTRACTS

VENTRICULAR FILLING CHARACTERISTICS IN AORTIC INSUFFICIENCY B.M. Harrison, MS, L.G. Christie, MD,FACC, S. Liberty, AS, E.A. Geiser, MD, M. Ariet, PhD, University of Florida, Gainesville, Florida To quantify left ventricular (LV) filling in isolated aortic insufficiency (AI), M-mode echocardiograms from 16 patients with cath-proven chronic AI, without clinical heart failure were compared to those of 10 normals. Echoes were analyzed by computer assisted digitization technique which provided LV maximum (EDD) and minimum dimensions, percent shortening and EDD wall thickness (WT). Peak rate of chamber expansion/filling (DD/DT/Dmax) normalized for EDD and the time to this peak filling rate (T) from onset LV expansion were calculated. RESULTS: Normals

68(1?4) P

HR 65(6.9) NS EDD 49.0(5.7) 69.6(6.1) c.05 WT B.l(l.6) 8.6 NS +DD/DT/Dmax 46.79(8.6) 27.9(20.0) c.05 T 103.2(36) 66(12.5) c.05 Values=group means (?SD) NS=Not Significant HR=Heart Rate While patients are few, separation into groups by conven- tional angio assessment showed mean peak filling rates znd also provided reasonable group separations: l+AI vs 53 mm2/sec, 2+AI vs 297, 3+AI vs 144 and 4+AI vs 19. Differ- ences between groups were significant (P < .05) for the first three categories (not for 3+ vs 4+). CONCLUSIONS: These data demonstrate: l)Peak filling occurs earlier in all patients with aortic insufficiency and is not related to the severity of regurgitation. 2)Peak fill- ing rate is blunted in AI vs normals before congestive heart failure and before left ventricular hypertrophy. 3) Degree of depression in peak filling rate may relate to the quantity of aortic regurgitation prior to congestive heart failure and/or left ventricular hypertrophy.

PREDICTIVE VALUE OF LEFT VENTRICULAR RELATIVE WALL THICK- NESS (R/TH) AND END SYSTOLIC DIMENSION IN THE PREOPERATIVE EVALUATION OF PATIENTS WITH CHRONIC AOSTIC REGURGITATION W. H. Gaasch, ?fD, FACC, J. D. Carroll, MD, H. J. Levine, MD, FACC, M. 6. Criscitiello, m, FACC. Tufts University School of Medicine and V.A. Medical Center, Boston, rass.

To assess the prognostic significance of preoperative echocardiographic (echo) data on the late results of aor- tic valve replacement (AVR) for chronic aortic regurgita- tion (AR), we examined serial pre & postop ethos from 32 patients (pts) with postop follow-up of l-6 yrs (mean 4). We measured LV end diastolic (ed) & end systolic (es) di- mensions (Ded & Des in mm/m2 BSA), ed wall thickness (Th), fractional shortening (FS%), ed radius/Th ratio (R/Th), and R/Th normalized for systolic pressure (P.R/Th).

Based on postop data, we defined 2 groups: 25 pts achieved a normal Ded (< 3.3) after AVR (group A) and 7 had persistent LV enlargement (group B). Preop data (mean ? SD) for the 2 groups are shown below.

Ded Des FS R/Th P*R/Th

Group A 37 2 3 24 ? 4 34 ? 6 3.4 + 0.4 520 ? 88 Group B 43 ! 5 31 ? 5 27 + 6 4.1 ? 0.3 667 + 58

Patients in group A had fewer postop symptoms and better 4-yr survival (96%) than those in group B (71%). In group B, 2 died (1 & 9 mos postop) with congestive heart failure (CHF); there were no CHF deaths in group A.

A preop R/Th > 3.8 (especially a P.R/Th > 600) has better predictive value (PV) for group B result than tDed, tDes, or +FS - but depending on the limits selected, indi- vidual parameters have poor sensitivity and/or specifici- ty. However, if preop P.R/Th is > 600 and Des is > 2.6, all group B pts are identified (PV 100%); all but one in group A had P.R/Th < 600 and/or Des < 2.6 (PV 96%).

Thus, pts at risk of persistent postop LV enlargement (with associated cardiac symptoms and reduced survival) can be identified by preop echocardiography.

MONDAY, APRIL 26, 1992 PM HYPERTENSION: ETHlLOGY AND TREATMENT 2:00-3:30

CHRONIC HEMODYNAMIC EFFECTS OF A HIGH SODIUM INTAKE Jay M. Sullivan, MD, FACC; Thomas E. Ratts, MD University of Tennessee Center for the Health Sciences, Memphis, Tennessee

The long-term hemodynamic effects of a high dietary sodium intake were studied in seven young normal sub- jects. After four days of a 10 mEq sodium, 60 mEq potassium diet, mean blood pressure (mBP) was 82.325.7 nmn Hg, cardiac index (CI) was 2.32tO.26 l/min/m;!, and total peripheral resistance (TPR) was 17782358 dyne set cmb5. After four to six days of a 200 mEq sodium, 60 mEq potassium diet, mBP rose to 84.3k7.9 mm Hg, CI to 2.53kO.23 l/min/m* and TPR fell to 1437+124 dyne set cmW5. After six months of unrestricted sodium intake, urinary sodium excretion (UNa) was 14O.lt20.6 mEq/24 hrs (p<.OOl), mBP remained at 83.1t5.2 mm Hg, CI rose to 3.11~0.38 l/min/m2 (pc.05) and TPR was 1268+160 dyne set cmW5. After 12 months UNa rose to 171.6~37 mEo/24 hrs (p<.OO5), while mBP remained at 82.4k6.8 arm Hg, CI at 3.08fO.44 l/min/m* (pc.05) and TPR at 1282+189 dyne set cmm5. Thus, cardiac index rises significantly with sodium intake in normal subjects and remains at a higher level for as long as 12 months. Blood pressure does not rise because TPR remains lower.

SODIUM AND POTASSIIJII FLUXES IN ERYTHROCYTES - A POSSIBLE GENETIC MARKER FOR ESSENTIAL HYPERTENSION Vladimir Janata, &ID; Zdenek Fejfar, MD FACC hon.; Ivo Pferovsky, MD;

, Hana Pistulkovd,;

Institute for Clinical and Experimental Medici- ne, Prague, Czechoslovakia.

Diffusion, active Na+K+-ATPase transport and that of active Na+, K+-co-transport are the ma- jor transport systems in erythrocytes. Defect in the active Na+, K+-co-transport was found in patients with essential hypertension and in some of their offsprings. Hence the measurement of the cation fluxes in the red cells might be a genetic marker for essential hypertension /Garay and Meyer 1979/. The method has been tested in repeated measurements over several months in 97 subjects /63 males, 34 females, 18-73 years ages/. 90% were between 20-60 years of age. The reproducibility of repeated estima- tion after several months was good mean varia- tion of the ratio of Na+/K+ fluxes in 9 subjects being 11%. In 33 normotensive subjects the mean ration was 3.2f0.22; in 14 patients with secon- dary hypertension of renal origin 3.1f0.44 while in 22 subjects with essential hypertension /sta- ge 2 WHO classification/ it was 1.81t0.15. Only some normotensive young subjects with family history of hypertension had the ratio below the level of 2.0. Treatment with hydrochlorothiazide did not influence the results. Simplified method of measurement of the cation fluxes in erythro- cytes may be promising for selecting normotensi- ve young subjects at risk of future hypertension before application of prophylactic measures.

March 1982 The American Journal of CARDIOLOGY Volume 49 911