Transtoracical Ecocardiographic Assessment of Severe Degenerative Aortic Stenosis with Normal Ejection Fraction and Low Transvalvular Gradient

Abstract

Purpose of the study: echocardiographic evaluation of the form of degenerative aortic stenosis (DAS) with preserved ejection fraction (EF) and low transvalvular gradient, in order to formulate the indication of valvular prosthesis as early as possible; retrospective observational study that includes patients admitted or sent for ambulatory evaluation by other medical services. The echocardiographic parameters used: systolic and diastolic indices, tissue and spectral, mitral and tricuspid veins, aortic orifice area, maximal aortic systolic velocity, maximal and medium aortic transvalvular gradient, myocardial mass index, volume of left atrium, left ventricular (LV) thickness. 42 patients with severe DAS and preserved EF, average age 71.7�3.85 years. Two groups were isolated: A - with increased gradient (22 patients) and B - with low gradient (20 patients). The gender distribution was comparable: women representing 33% in group A versus 30% in group B. The average age of women in both groups was higher than that of the men: in group A: 72�8 years in the case of women vs. 67�6 years in the case of men and in group B 72�3.5 years in women vs. 68�6 years in men. Apical displacement of the mitral ring: 14�2mm in lot A vs. 11�2mm in lot B. Myocardial mass index: 120 � 9g/m2 in lot A vs. 126 � 12g/m2 in lot B. Left ventricular filling ratio E/e�: 8�2 in lot A vs. 13�2 in lot B; maximum aortic systolic velocity: 4.3�0.9m/s in lot A vs. 3.1�0.8m/s in lot B; maximum gradient: 73.9�10mmHg in lot A vs. 37�12mmHg in lot B; aortic orifice area: 0.80�10.5 in lot A vs. 0.79�0.07 in lot B. Statistical analysis shows the Pearson correlation index r with the highest values of 95% at the significance threshold between the aortic orifice area and the valve opening (r=0.87), the ratio E/e� (r=-0.85) and diastolic thickness of the posterior wall of the aortic left ventricle (r = 0.78). Aortic stenosis with preserved ejection fraction and low gradient was more common in men. The filling ratio E/e� was increased (13 � 2) in group B, suggesting the increase of filling pressures of LV in patients with DAS and low transvalvular gradient. Tissue spectral systolic and longitudinal velocities were lower in group B, suggesting the onset of systolic LV dysfunction. The aortic valve opening and the E/e� ratio showed the highest correlation coefficient with the area of the aortic orifice in both groups. The myocardial mass index and the thickness of the walls of the LV cavity are similar in the two groups, suggesting that the reduction of the LV cavity through hypertrophy may not explain, at least in totality, the form of DAS with low gradient and preserved ejection fraction.

The Acute Hemodynamic Effects of Caffeine During Different Body Positions in Normotensive Young Adults

“…To take into account the postural, gravitationally induced effects on BP, it should be mentioned that the head-down Trendelenburg position leads to a temporary increase of venous return and preload, cardiac output and perfusion index [28]. Certainly, the stroke volume variation is subjected to the body posture [29,30], but the pressure hemodynamic effects, especially in people with hypotension, heart failure or aortic stenosis are the subject of dispute between various authors [31][32][33]. In clinical practice, the Trendelenburg position is used mainly with small or medium angles of inclination, in which there is no significant influence in the dominant parasympathetic cardiac control [34].…”