Israel Medical Association Journal

Background: Rapid reperfusion of an infarct-related artery is crucial for the successful treatment of ST elevation myocardial infarction. Every effort should be made to shorten door-to-balloon time.

Objectives: To investigate whether bypassing the emergency room (ER) has a positive influence on door-to-balloon time in patients presenting with ST elevation myocardial infarction (STEMI) and whether the reduction in door-to-balloon time improves patients’ clinical outcome.

Methods: We analyzed data of 776 patients with STEMI[1] from the 2004 and the 2006 Acute Coronary Syndrome Israeli Survey (ACSIS) registry. The ACSIS[2] is a biennial survey on acute myocardial infarction performed in all 25 intensive cardiac care units in Israel during a 2-month period. Twenty-five percent of patients (193 of 776) arrived directly to the intensive cardiac care unit (ICCU) and 75% (583 of 776) were assessed first in the ER[3]. We compared door-to-balloon time, ejection fraction, 30 days MACE (major adverse cardiac and cerebrovascular events) and 30 days mortality in the two study groups.

Results: There was significantly shorter door-to-balloon time in the direct ICCU group as compared with the ER group (45 vs. 79 minutes, P < 0.002). Patients in the direct ICCU group were more likely to have door-to-balloon time of less than 90 minutes in accordance with ACC/AHA guidelines (88.7% vs. 59.2%, P < 0.0001). Moreover, patients in the direct ICCU group were less likely to have left ventricular ejection fraction < 30% (5.4% vs. 12.2%, P = 0.045) and less likely to have symptoms of overt congestive heart failure. Lastly, 30 days MACE[4] was significantly lower in the direct ICCU group (22 vs. 30%, P < 0.004).

Conclusions: There is significant reduction of the door-to-balloon time in the direct ICCU admission strategy. This reduction translates into improvement in clinical outcome of patients. It is reasonable to apply the direct ICCU strategy to patients with STEMI.

Background: Previous studies have documented that reduction in QT dispersion after thrombolytic treatment in acute myocardial infarction depends on reperfusion status as well as infarct site. Primary percutaneous transluminal coronary angioplasty as compared with thrombolytic therapy has been shown to result in higher patency rates of the infarct vessel.

Objectives: To evaluate whether primary PTCA has a more favorable effect on reducing QT dispersion in patients with acute MI as compared to thrombolytic treatment.

Methods: The study population included 42 consecutive patients (33 men, mean age 58 ± 11 years) with acute Ml (24 anterior wall, 18 inferior wall) who were treated with primary PTCA (group A, n 21) or thrombolytic therapy (group B, n = 21) at 3.9+2 hours after symptom onset. QT intervals were measured before and 24 hours after treatment.

Results: On the admission electrocardiogram, patients with anterior Ml had higher values of QT and QTc dispersions than patients with inferior Ml (52±9 vs. 36±9 msec, R<0.05 and 61+4 vs. 56+4 msec, P=0.002, respectively). There was a significant reduction in QT and QTc dispersions from admission to 24 hours in all patients (from 50+9 to 37+9 msec, P<0.001 and from 59+5 to 42+5 msec, P<0.001. respectively), and also in group A (from 49±8 to 32±5 msec. P<0.001 and from 58+5 to 38+3 msec, P<0.001, respec­tively) and in group B patients (from 51+10 to 42+10 msec. P<0.01 and from 60±4 to 46±5 msec, P<0.001, respec­tively). QT and QTc dispersions were found to be shorter in group A at 24 hours after treatment than in group B (32 + 5 vs. 42+10 msec, P<0.001 and 38+3 vs. 46+5 msec, P<0.001. respectively).

Conclusions: Reperfusion therapy with primary PTCA or thrombolytic agents reduces QT and QTc dispersions in acute Ml. QT and QTc dispersions after reperfusion treatment are shorter with primary PTCA than with thrombolytic therapy.