[Critical left ventricular volume in aortic stenosis in first year of life: its importance in patients selection candidates to univentricular surgical correction pos-valvotomy].
OBJECTIVE
Analysis of critical end diastolic left ventricular volume (EDLVV), defined as the lowest acceptable volume to keep cardiac output, in the selection of patients with post-valvotomy aortic stenosis, candidates to univentricular correction.


METHODS
A retrospective study in 21 patients with aortic stenosis, during the first year of life, and 232 patients compiled from literature. Values of end diastolic volume (EDLVV), from 20 to 60 ml/m2 were determined as normal. The EDLVV of deceased patients was compared to that from survival patients. A correlation between the age and EDLVV was carried out at the time of valvotomy, between the groups. Finally, the critical EDLVV through the theoretical relationship between the EDLVV and heart rate for different ejection fractions and designated cardiac indexes (CI): 2,000 and 2,500 20-60 ml/min/m2 was determined.


RESULTS
For EDLVV values < 20 ml/m2 and > 60 ml/m2, there was statistical significance between deceased and survival patients (p < 0.0001). However, in the range between 20 and 60 ml/m2, that significance was lower (p = 0.0309). A greater incidence of death took place among those who showed it in the first week of life. For a CI of 2,500 ml/min/m2 and a heart rate (HR) of 140 bpm, critical EDLVV will be 26 ml/m2 if left ventricular ejection fraction (LVEF) is 0.70, and 44.5 ml/m2, if LVFE is 0.40.


CONCLUSIONS
The analysis of critical end diastolic left ventricular volume (EDLVV) can add another parameter in the indication of univentricular correction in patients with post-valvotomy aortic stenosis, during the first year of life.
Santos
Marco Aurélio
MA
Instituto Nacional de Cardiologia Laranjeiras, Rio de Janeiro, RJ. masantos@cardiol.br
Azevedo
Vitor Manuel Pereira
VM
Cunha
Maria Ourinda Mesquita da
MO
D001024:Aortic Valve Stenosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D001938:Brazil / Q000453:epidemiology; D002404:Catheterization; D006801:Humans; D007231:Infant, Newborn; D018579:Patient Selection; D012189:Retrospective Studies; D013318:Stroke Volume / Q000502:physiology*; D016276:Ventricular Function; D016277:Ventricular Function, Left / Q000502:physiology*