T-Wave Alternans in diabetic patients after myocardial infarction treated by percutaneous interventions

Authors:
T. Zielinska¹, A. Zielinska-Meus², A. Musialik-Lydka¹, O. Kowalski¹, P. Jarski¹, P. Pruszkowska¹, B. Sredniawa¹, J. Obrebska¹, K. Oleszczyk², Z. Kalarus¹, ¹Silesian Center for Heart Diseases - Zabrze - Poland, ²Upper Silesian Rehabilitation Center "Repty" - Tarnowskie Gory - Poland,

Topic(s):
Diabetes

Citation:
European Heart Journal ( 2007 ) 28 ( Abstract Supplement ), 464

The aim of his study was to assess the risk of sudden cardiac death (SCA) in patients with diabetes who have had acute myocardial infarction (AMI).

Methods: T- Wave Alternans (TWA) was measured in 202 consecutive patients (pts) within 5-7 days after AMI treated by percutaneus interventions (PCI). The Cambridge Heart's HearTwaveTM System was used for those examinations. The glucose tolerance test was performed in clinical asymptomatic pts. The pts were divided for four groups (gr.) in based on results of glycaemia: gr.1–55pts with diabetes mellitus (DM), gr.2-33pts with IGT (impaired glucose tolerance), gr.3-41pts with IFG (impaired fasting glucose), gr.4-74pts with normal glucose regulation. Gr.1 was divided on 2 subgroups (sgr.): sgr.1A-52pts. with DM type 2 and diabetes duration mean 4±3,6 years, sgr.1B-9pts with DM de novo (DMn). The comparative analyze between groups and subgroups was done by Fischer's exact test. The level of glycated hemoglobin (HbA1c) and frequency of TWA positive and negative were compared in diabetic pts with poorly controlled diabetes (PGC) – HbA1c ≥ 7% and well controlled diabetes (WGC)-HbA1c< 7%. Correlation between HbA1c and CK-MBmax were also assessed.

Results: TWA positive was present in 40pts (73%) gr.1: 35pts (87%) from sgr.1A and 5pts (55%) sgr.1B. Positive TWA was present in 8pts (24%) gr.2, 4pts (9,5%) gr.3 and 18pts (24%) gr.4. TWA negative was present in 15pts (27%) gr.1: 11pts (20%) sgr.1A, and 4pts (44%) gr.1B. TWA positive was found significantly greater in gr.1 than in gr.4 RR 3,26 (95%CI 2,17-5,28), p<0,001, as well as in pts with impaired glucose homeostasis (gr.2+gr.3) RR 3,94 (95%CI 2-44-6,36), p<0,001. In PGC group TWA positive was found in 28pts (96%) and TWA negative in 1pts (4%). In WGC group (n=26pts) TWA positive was present in 11pts (42%) and TWA negative in 5pts (19%). TWA positive was present significantly greater in PGC group than in WGC group, p<0,01, RR 4,30 (95%CI 0,71-26,07). Significant correlation was found between CK-MBmax and HbA1c in PGC pts, p<0,05, r=0,48.

Conclusions: 1. The risk of sudden cardiac death in patients with and without diabetes after acute myocardial infarction is significantly greater in diabetic subjects than normoglycaemic ones. This risk increases with diabetes duration. 2. The risk of sudden cardiac death is related with HbA1c level in patients with poorly glicaemic control. 3. Poorly controlled glucose has significantly influence on CK-MB max.