Hemodynamic patterns for symptomatic presentations of severe aortic stenosis

The aim of this study was to investigate intracardiac hemodynamic idiosyncrasies responsible for various presentations of severe aortic stenosis (AS).

Syncope, dyspnea, and chest pain are well-established indications for aortic valve replacement in patients with severe AS. Patients' survival is limited once they develop symptoms from AS, and survival depends on what type of symptoms a patient develops. We hypothesized that there would be a relationship between the type of AS symptoms and intracardiac hemodynamics as well as AS severity.

We analyzed 498 patients (men: 58.4%, 66 ± 12 years of age) with severe AS and normal left ventricular ejection fraction from 2003 to 2009 who had comprehensive echocardiography examination for AS. The study population was divided into 4 groups based on presenting symptom(s) (341 in group I, asymptomatic; 15 in group II, syncope; 110 in group III, dyspnea; 32 in group IV, chest pain). Echocardiographic measurements for cardiac structure, function, and intracardiac hemodynamic parameters were compared among these 4 groups.

Mean aortic valve pressure gradient and aortic valve area were 57.1 ± 15.2 mm Hg and 0.74 ± 0.19 cm(2), respectively. AS severity based on mean gradient and aortic valve area was similar among 4 groups. Compared with the asymptomatic group, symptomatic patients were older and had lower cardiac output, and higher E/e' ratio while having a similar aortic valve area and gradient. Group II (syncope) displayed smaller LV dimension, stroke volume, cardiac output, left atrial volume index, and E/e' ratio. Conversely, group III (dyspnea) was found to have the worst diastolic function with largest left atrial volume index and highest E/e' ratio.

Among patients with severe AS, their symptoms are often linked to specific hemodynamic patterns associated with AS: smaller left ventricular cavity and reduced output for syncope versus more advanced diastolic dysfunction for dyspnea. Hence, comprehensive intracardiac hemodynamics including diastolic function and stroke volume need to be evaluated in addition to aortic valve area and pressure gradient for assessment of AS.