Diagnostic utility of post-extrasystolic heartbeat in the evaluation of myocardial contractile reserve

Utilidad diagnóstica del latido post-extrasistólico en la evaluación de reserva contráctil miocárdica

The post-extrasystolic heartbeat (LPE) as a ventricular inotropic stimulus would allow to identify ischemic areas and, therefore, territories irrigated by injured arteries that should be operated on. The objective of the present study is to determine the operative characteristics of the LPE to evaluate myocardial ischemia with respect to the "gold test" (myocardial perfusion with isonitriles). Symptomatic patients with a positive myocardial perfusion test for ischemia were taken to left catheterization. According to Simpson's method, radial shortening during a normal systole was compared in each segment with a subsequent post-extrasystolic pause. The presence or absence of an increase in contraction was recorded and each segment was compared with the non-invasive study. In 140 myocardial segments the presence of post-extrasystolic hypercontractility (HCPE) was compared, the operative characteristics of this diagnostic method were obtained and the results were compared with those of the non-invasive test. The data of sensitivity (82%) and specificity (65%) of the LPE are close to those reported by the "gold test". The different operative characteristics are analyzed and it is concluded that the greatest utility of the LPE is found when obtaining a negative result. The high sensitivity of the LPE to identify myocardial ischemia as well as the simplicity to obtain it, gives us a new tool in the hemodynamics room to define which arteries should be operated at the same moment of the diagnostic catheterization, without the gold test losing its diagnostic utility. Abbreviations: post-extrasystolic heartbeat (LPE), post-extrasystolic hypercontractility (HCPE).

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