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Transfemoral Transcatheter Aortic Valve Implantation
Published in Theo Kofidis, Minimally Invasive Cardiac Surgery, 2021
The wire should be advanced gently to probe the aortic orifice. Once the valve is crossed, the catheter can be advanced into the left ventricle guided by the wire. This wire can then be exchanged with a stiffer exchange length wire. The standard wire that can be used is the Amplatz Extra-Stiff 0.035” wire (Cook Medical, Bloomington, IN, USA) or the Amplatz Super Stiff™ wire (Boston Scientific, Marlborough, MA, USA), which can be manually shaped to conform to the LV cavity. Other alternatives are the pre-shaped TAVI guidewires such as the Confida Guidewire (Medtronic, Fridley, MN, USA) and the Safari Guidewire (Boston Scientific, Marlborough, MA, USA).
Aortic Stenosis
Published in Takahiro Shiota, 3D Echocardiography, 2020
Patrizio Lancellotti, Tadafumi Sugimoto, Raluca Dulgheru
The aortic valve consists of a complex of structures surrounding the aortic orifice along the outflow tract of the left ventricle (LV).5 Typically, the valve has three leaflets, which are semilunar in shape. The cups are inserted into a fibrous connective tissue sleeve, which is attached to the aorta media above (the Valsalva sinuses and the sinotubular junction). Below, the cusps are attached to the myocardium of the LV outflow tract and to the anterior mitral leaflet (virtual basal ring), below the anatomical ventriculo-aortic junction. Hence, the true anatomical aortic annulus is not actually the ring projected at the most basal leaflet insertion - as usually defined and measured with various imaging techniques - but a crown-like 3D structure. Of note, the size of the aortic annulus and the root is influenced by inner pressure and is dynamically changing during the cardiac cycle by 12% and 16%, respectively.6 Each cusp is attached along its curved edge, and the cusps meet at three commissures that are equally spaced along the circumference of the sleeve at the supra-aortic ridge. In a normal aortic valve, the cups are symmetrical, mobile, and free at the commissures, with equal overlap on closure. The cusps are called left coronary, right coronary, and noncoronary cusps based on the location of the coronary ostia.7
Dynamics of the Aortic Valve
Published in Mano Thubrikar, The Aortic Valve, 2018
In summary, since angiographic projections most often show an oblique view, i.e., the X-ray beam is not exactly along the axis of the aorta, the margins of the valve orifice may appear straight or curved. This is because oblique projection of a curved line can be a straight line. In other words, a circular orifice can project itself as partly triangular. However, it is clear that the normal valve orifice is not triangular since a triangle will not project with curved borders. Also, the orifice decreases continuously during systole causing its shape to change. The shape of the aortic orifice, determined with two-dimensional echocardiography, is discussed in Chapter 6.
Antihypertensive treatment and risk factors for syncope in asymptomatic aortic stenosis patients with hypertension
Published in Clinical and Experimental Hypertension, 2022
Meihua Wu, Ping Gu, Qianqiang Cao, Aibin Gong, Wenliang Tan, Dezhi Hong
Syncope is one of the most urgent clinical symptoms, occurring suddenly without warning. Restricted cardiac output caused by a narrowed aortic orifice with excessive progression was regarded as the major cause of syncope in patients with AS. However, reports mention that other mechanisms of syncope development in AS exist, such as inappropriate reflex vasodilation, which is possibly mediated by a sudden rise in LV pressure and an increase in LV wall stress (25), or primary cardiac arrhythmia. However, there are few reports about syncope during antihypertensive treatment in AS patients with hypertension. In the present study, patients with asymptomatic moderate to severe AS were followed up for an average of 28 months, and 8 cases of syncope occurred in antihypertensive group, while 5 cases of syncope occurred in the normotensive group; the difference between the two groups was not statistically significant. Most of our patients were treated with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers; many were taking beta blockers, diuretics, and calcium channel blockers. Moreover, consistent with published literature (26), our results indicate that syncope was not associated with any specific drug or class of drugs. Conversely, previous research has shown that more intensive therapy is associated with a higher risk of syncope; but has no effect on falls or orthostatic hypotension (27).
Clinical outcomes of self-expandable vs. balloon-expandable TAVI for severe aortic stenosis
Published in Acta Cardiologica, 2020
Jodie Li Mei Tham, Heath Adams, Sarang Paleri, Christine Wright, Jim Dimitriou, Andrew Newcomb, Andrew I. MacIsaac, Robert J. Whitbourn, Sonny C. Palmer
This analysis demonstrated higher mean aortic valve gradients and lower effective aortic orifice areas in the BEV group. This trend has been observed in matched comparisons of SAPIEN and CoreValve devices, with the former associated with higher aortic valve gradients [19]. This is likely a result of the BEV design, namely the supra-annular leaflet position of the TAVI. In this study, differences in haemodynamics did not translate to a higher rate of BEV failure or difference in clinical outcomes. Low rates of all-cause mortality overall were observed with no difference between SEV vs. BEV devices. This is consistent with 30 d all-cause mortality rates seen in the literature, ranging from 1.3 to 9.5% for CoreValve and Evolut-R, and 1.3–9.0% for SAPIEN, SAPIEN-XT and SAPIEN-3 devices [20,21].
Transthoracic echocardiographic versus cardiometry derived indices in management of septic patients
Published in Egyptian Journal of Anaesthesia, 2020
Mohamed Elsayed Afandy, Sarah Ibrahim El Sharkawy, Amany Faheem Omara
Stroke volume (SV) was measured by multiplying the aortic valve area in the velocity-time integral of aortic blood flow (VTIAo) using the formula SV (ml) = (LVOTa) x (VTIAo). The aortic valve area was calculated from the measurement of the left ventricular outflow tract (LVOTd) measured at the insertion of the aortic cusp from the left para sternal axis view. The aortic valve area (LVOTa) was then calculated as π x (LVOTd/2)2, as the diameter of the aortic orifice is assumed to remain constant.