A SINGLE DOSE OF GTN UNMASKS DIASTOLIC FILLING ABNORMALITIES IN NON-INSULIN DEPENDENT DIABETES MELLITUS.
GA Whaiiev*, W Bagg, RN Doughty, HJ Walsh, P Drury, G Braatvedt, N Sharpe.
Cardiovascular Research Laboratory, Department of Medicine, University of Auckland School of Medicine, Auckland, NEW ZEALAND.
Type 1 (IDDM) and type 2 (NIDDM) diabetics have lower E:A ratio (compared to age matched controls) in the absence of both left ventricular hypertrophy (LVH) and systolic impairment. The aim of the current study was to classify diastolic function in 35 patients (pts) with NIDDM and poor glycaemic control (HBA,1c > 9%). Pts with systolic dysfunction were excluded and no pts met ASE criteria for LVH (IVS and/or PW >l I mm). Pulsed wave Doppler mitral inflow was recorded before and after a single dose of glyceryl trinitrate (GTN, 40mg) to achieve preload reduction. Diastolic filling was classified into five categories: normal (0), abnormal relaxation (1), pseudo-normalization (2), reversible restriction (3) or non-reversible restriction (4).
Results: Mean age 56.6 yrs, LVEDD 52.3 (6.0) mm, LVESD 34.4 (6.3) mm, IVS 9.3 (1.13) mm, PW 9.5 (1.23) mm, FS = 33.1 (5.6)%. Pre GTN, 22 pts had abnormal relaxation (1) and 13 had normal (0) filling patterns. After GTN, all pts had an abnormal (1) filling pattern. After administration of GTN, all pts had an E:A ratio <1.0. Patients were then reclassified:
|
PHASE |
0 |
1 |
2 |
3 |
4 |
|
Pre-GTN |
13 |
22 |
0 |
0 |
0 |
|
Post GTN |
0 |
22 |
13 |
0 |
0 |
E:A ratio fell significantly with GTN for 0.82 to 0.68 (p<0.001) and deceleration time increased from 225.8 to 330.9 (p<0.001).
Conclusion: These data are the first to demonstrate the pseudonormalised filling pattern and thus
advanced diastolic dysfunction, in the absence of either LVH or systolic impairment in NIDDM. These
data highlight the role of preload reduction for thorough assessment of diastolic function, in diabetics.
