Final answer:
The intracardiac pressure that will most likely be increased in patients with severe valvular aortic stenosis is the left ventricular pressure at end-diastole due to the left ventricle working against the increased resistance of the narrowed aortic valve and potentially increased end-diastolic volume.
Step-by-step explanation:
The intracardiac pressure that will most likely be increased in patients with severe valvular aortic stenosis is left ventricular pressure at end-diastole. Aortic stenosis is characterized by the narrowing of the aortic valve, which impedes the flow of blood from the left ventricle into the systemic circulation. During ventricular systole, the left ventricle contracts to push blood through the aortic valve and into the aorta. If the aortic valve is narrowed, as in the case of aortic stenosis, the left ventricle has to generate a much higher pressure to overcome the resistance of the stenotic valve, which can lead to an increase in left ventricular pressure even at end-diastole, due to the increased resistance that the ventricle is working against during systole.
Furthermore, in valvular aortic stenosis, following the isovolumic contraction phase, the stroke volume may be reduced due to the outflow obstruction, leaving more blood in the left ventricle at the end of systole, thus potentially increasing the end-diastolic volume (EDV) and pressure.