Diabetes and ST Elevation Myocardial Infarction: How successful is intravenous thrombolysis for the diabetic heart?

doi:10.2337/diacare.25.10.1890

HOME

HELP

FEEDBACK

SUBSCRIPTIONS

Letters: Observations
Letter

Diabetes and ST Elevation Myocardial Infarction

How successful is intravenous thrombolysis for the diabetic heart?

Michael N. Zairis, MD, Stamatis S. Makrygiannis, MD, Olga A. Papadaki, MD, Anastassios G. Lyras, MD, John P. Kouzanidis, MD, Olga S. Ampartzidou, MD, Stelios M. Handanis, MD, Spyros M. Argyrakis, MD and Stefanos G. Foussas, MD, FESC, FACC

¹ From the Department of Cardiology, Tzanio Hospital, Piraeus, Greece

Early resolution of ST-segment elevation is associated withenhanced clinical outcome following ST elevation myocardialinfarction (STEMI). According to previous studies, the incidenceof successful reperfusion following STEMI treated with thrombolyticregimen is similar for type 2 diabetic subjects and nondiabeticsubjects as assessed by "snapshot" electrocardiographic or angiographiccriteria (1). Nevertheless, type 2 diabetic subjects thrombolysedbecause of STEMI still seem to fare worse, manifesting impairedleft ventricular function or long-term prognosis (2).

The aim of this prospective study was to test the hypothesisthat type 2 diabetic subjects may have a protracted ST-segmentrecovery, even while achieving reperfusion criteria, comparedwith nondiabetic subjects. Therefore, continuous ST-segmentmonitoring was used, as it is considered to be more reflectivenot only of infarct-related artery patency status, but of actualtissue reperfusion (3).

The study cohort included 137 patients with STEMI: 105 nondiabeticsubjects and 32 type 2 diabetic subjects (age 58.9 ±10.3 vs. 67.5 ± 7.1 years, respectively; P < 0.001)without history of prior myocardial infarction or coronary arterybypass surgery. Each patient received either streptokinase ortissue-type plasminogen activator (t-PA) in $<=$ 6 h from index painand was connected to the Eagle 4000 Monitor immediately afteradmission. All patients integrated to this study attained thecriterion of steady $>=$ 50% ST-segment recovery within 90 min afterthrombolysis initiation. Significant differences in the twogroups were not found concerning time elapsed from index painto initiation of thrombolytic procedure, location of STEMI,or thrombolytic agents used.

The time required for $>=$ 50% ST-segment steady resolution was significantlygreater in type 2 diabetic subjects than in nondiabetic subjects(68.8 ± 15 vs. 45.8 ± 17.9; P < 0.001). Moreover,the former had higher subsequent peak creatin kinase myocardialtype B isoenzyme release than the latter (P < 0.001). Accordingto multivariate linear regression analysis, type 2 diabeticsubjects were independently and positively related to the timefor $>=$ 50% ST-segment recovery (P < 0.001).

In accordance to the original hypothesis, the present studyshowed that type 2 diabetic subjects required almost 50% moretime to achieve satisfactory ST-segment elevation recovery.The diminished benefit from thrombolysis may be attributed toseveral diabetes-induced disorders from diffuse coronary arterydisease, metabolic derangements, complexity of the culprit atheromaticplaque, microangiopathy including endothelial dysfunction, anddiminished flow reserve, to impaired glucose utilization andaccumulation of fatty acid intermediates (4). The results ofthe present study imply that the retardation in achievementof satisfactory reperfusion in the myocardial cells, as assessedby ST-segment elevation resolution, may at least partially accountfor the subsequent detrimental effect on diabetic hearts whensuffering STEMI. If these findings are validated with largerstudies, a more aggressive therapeutic approach might provesuitable for type 2 diabetic subjects with STEMI.

Footnotes

Address correspondence to Dr. Michael N. Zairis, AlkiviadouStr 273, Piraeus, Greece. E-mail: zairis{at}hellasnet.gr.

References

Gustafsson I, Hildebrandt P, Seibaek M, Melchior T, Torp-Pedersen C, Kober L, Kaiser-Nielsen P: Long-term prognosis of diabetic patients with myocardial infarction: relation to antidiabetic treatment regimen. The TRACE Study Group. Eur Heart J 21: 1937–1943, 2000[Abstract/Free Full Text]
Strandberg LE, Ericsson CG, O’Konor ML, Bergstrand L, Lundin P, Rehnqvist N, Tornvall P: Diabetes is a strong negative prognostic factor in patients with myocardial infarction treated with thrombolytic therapy. J Intern Med 248: 119–125, 2000[Medline]
de Lemos JA, Braunwald E: ST segment resolution as a tool for assessing the efficacy of reperfusion therapy (Review Article). J Am Coll Cardiol 38: 1283–1294, 2001[Abstract/Free Full Text]
Aronson D, Rayfield EJ, Chesebro JH: Mechanisms determining course and outcome of diabetic patients who have had acute myocardial infarction (Review Article). Ann Intern Med 126: 296–306, 1997[Abstract/Free Full Text]