Article

Determinantes de la reserva contráctil en la zona del infarto. Estudio cuantitativo mediante ventriculografía de contraste con dobutamina

Servicio de Cardiología. Hospital Clínico Universitario. Valencia
Revista Espa de Cardiologia (Impact Factor: 3.79). 07/2013; 53(5):617–624. DOI: 10.1016/S0300-8932(00)75139-6

ABSTRACT

Objective
The aim of this study was to relate the contractile reserve in infarction segments to the dysfunction at rest and to the residual coronary stenosis.

Methods
The study group consisted of 95 patients with a first myocardial infarction. Contrast left ventricular at baseline and after dobutamine infusion at 7.5 Êg/kg/min and coronary angiograms were performed. The centerline method was used to quantify the extent of dysfunction (percentage of chords with dysfunction in the territory of the infarction artery) and its maximum severity (maximum units of standard deviation [SD] below the normal wall motion reference). Reduction of dysfunction extent with dobutamine was measured.

Results
On increasing baseline dysfunction severity, both the magnitude of the response to dobutamine (. 2 SD [n = 12] = 33 ±} 19%, > 2 SD ≤ 3 SD [n = 20] = 20 ±} 16%, > 3 SD ≤ 4 SD [n = 35] = 16 ±} 19%, > 4 SD ±} 5 SD [n = 15] = 9 ±} 13%, > 5 SD [n = 13] = 3 ±} 4%, p = 0,0001), and the number of patients with a significant (. 15%) positive response (. 2 SD = 12 [100%], > 2 SD ≤ 3 SD = 11 [55%], > 3 SD ≤ 4 SD = 17 [49%], > 4 SD ≤ 5 SD = 3 [20%]; > 5 SD = 0%, p < 0,0001) decreased. There were no differences in dobutamine improvement among the subgroups with (n = 84) or without (n = 11) significant stenosis in the infarction artery (18 ±} 15 vs 16 ±} 18%), or between the subgroups with a patent (n = 76, 18 ±} 19%) or occluded (n = 19, 11 ±} 11%) artery.

Conclusions
Dobutamine response is related to dysfunction severity in the infarction area: when the severity is ≤ 2 (high positive response prevalence) or > 5 (high negative response prevalence), dobutamine testing does not seem indicate. The existence of residual coronary stenosis does not attenuate contractile reserve at low dobutamine doses.

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