Assertion: ventricular systole | /r/HasProperty | about to begin
Facets:
Source sentences:
text: The contractions of atrial systole fill the left ventricle with oxygen-enriched blood through the mitral valve; when the left atrium is emptied or closed, left atrial systole is ended and ventricular systole is about to begin.
text: The contractions of atrial systole fill the left ventricle with oxygen-enriched blood through the mitral valve; when the left atrium is emptied or closed, left atrial systole is ended and ventricular systole is about to begin.