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57 result(s) for "Sinus of Valsalva - physiopathology"
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Spatiotemporal Complexity of the Aortic Sinus Vortex as a Function of Leaflet Calcification
Several studies have shown the variation of aortic sinus structures’ hemodynamics with different flow and geometric characteristics. They have also correlated aortic sinus hemodynamics with the progression and evolution of calcific aortic valve disease (CAVD). This study aims at visualizing aortic sinus fluid structure variations as functions of different leaflet calcification degrees and assessing their potential relationship with CAVD. A degenerated 23 mm Carpentier-Edwards Perimount Magna valve extracted from a redo-surgery patient was implanted in an aortic root model and tested in a pulse duplicator left heart simulator. The valve has 3 leaflets with 3 different levels of calcium distribution: mild, moderate and severe. High-speed imaging and particle image velocimetry were performed to assess sinus vortices, leaflet tip position and velocity along with shear stress. Results have shown that (a) aortic sinus vortices initiation, entrapment and evolution varied with different calcified leaflet exposure; (b) higher velocities in the sinus were calculated with the mildly calcified leaflet compared to the moderately and severely calcified ones; (c) during systole, the mildly calcified leaflet sinus case shows the most spread-out and higher ranges of shear stress probabilities and highest magnitudes going from (− 1.5 to + 1.8 Pa) compared with (− 1.0 to + 1.0 Pa) for moderately and severely calcified leaflets. The higher the calcification degree the lower the shear stress range and likelihoods of having higher shear stress. This holds in diastole as well. This study shows the impact of calcification on the aortic sinus flow structures.
The Effect of Valve-in-Valve Implantation Height on Sinus Flow
Valve-in-valve transcatheter aortic valve replacement (VIV-TAVR) has proven to be a successful treatment for high risk patients with failing aortic surgical bioprostheses. However, thrombus formation on the leaflets of the valve has emerged as a major issue in such procedures, posing a risk of restenosis, thromboembolism, and reduced durability. In this work we attempted to understand the effect of deployment position of the transcatheter heart valve (THV) on the spatio-temporal flow field within the sinus in VIV-TAVR. Experiments were performed in an in vitro pulsatile left heart simulator using high-speed Particle Image Velocimetry (PIV) to measure the flow field in the sinus region. The time-resolved velocity data was used to understand the qualitative and quantitative flow patterns. In addition, a particle tracking technique was used to evaluate relative thrombosis risk via sinus washout. The velocity data demonstrate that implantation position directly affects sinus flow patterns, leading to increased flow stagnation with increasing deployment height. The particle tracking simulations showed that implantation position directly affected washout time, with the highest implantation resulting in the least washout. These results clearly demonstrate the flow pattern and flow stagnation in the sinus is sensitive to THV position. It is, therefore, important for the interventional cardiologist and cardiac surgeon to consider how deployment position could impact flow stagnation during VIV-TAVR.
Effect of Left and Right Coronary Flow Waveforms on Aortic Sinus Hemodynamics and Leaflet Shear Stress: Correlation with Calcification Locations
Coronary flow induces hemodynamic alterations in the aortic sinus region. The objectives of this study are to: (1) investigate the differences among sinus hemodynamics and leaflet wall shear stresses engendered by the left versus right versus non-coronary flow and (2) correlate respective wall shear stresses with leaflet calcification in patients. A left heart simulator flow loop with a tunable coronary circuit provided physiological coronary flow waveforms corresponding to the left coronary cusp case (LCC), right coronary cusp case (RCC), and non-coronary cusp case (NCC). High spatio-temporal resolution particle image velocimetry was conducted to quantify leaflet wall shear stress and sinus vorticity fields and to measure aortic leaflet tip kinematics. Thirty-one patients with severe calcific aortic valve disease were segmented from CT data for the calcific volumes in their respective left, right, and non-coronary cusps. Leaflet tip position during systole shows the RCC has a wider leaflet opening compared to LCC and NCC. Velocity and vorticity fields combined with leaflet position data show that sinus vorticity is diminished (peak ~ 43 s−1) in the LCC while RCC and NCC maintain high vorticity (~ 1200 and ~ 950 s−1 respectively). WSS magnitudes greater than 0.3 Pa show 20 and 81% greater occurrences in the LCC and RCC respectively compared to NCC. Significant differences [X2 (2, n = 31) = 7.31, p = 0.0258] between the calcification levels in each cusp of the patient population. Coronary flow differences between LCC, RCC, and NCC show significant impact on leaflet kinematics and sinus flow hemodynamics. Clinical data correlations of the coronary flow cases indicate the left coronary cusp has a higher likelihood of calcification compared to the right.
Physiological and clinical relevance of anomalous right coronary artery originating from left sinus of Valsalva in adults
ObjectiveTo examine physiological and clinical relevance of an anomalous right coronary artery originating from left sinus of Valsalva (right ACAOS) with interarterial course in adults.Methods and resultsFor physiological assessment, fractional flow reserve (FFR) during dobutamine challenge was measured in 37 consecutive adult patients with lone right ACAOS with interarterial course. At baseline, mean FFR was 0.91±0.06, declining to 0.89±0.06 upon dobutamine infusion (p<0.001). Dobutamine stress FFR was significant (≤0.8) in three patients (8.1%), two of whom were surgically treated. Following surgery, dobutamine stress FFR rose from 0.76 to 0.94 and 0.76 to 0.98. Remodelling index (r=0.583, p=0.002), minimal lumen area (diastole: r=0.580, p=0.002; systole: r=0.0618, p<0.001) and per cent area stenosis (r=–0.550, p=0.004), measured by intravascular ultrasound, correlated with dobutamine stress FFR. To assess the clinical relevance, follow-up data of 119 patients with lone right ACAOS with interarterial course were analysed retrospectively. Two deaths occurred during a median follow-up period of 4 years, for a mortality rate of 0.34 per 100 person-year. No instances of myocardial infarction were recorded and one patient did undergo surgical revascularisation in the course follow-up.ConclusionsMost instances of lone right ACAOS with interarterial course discovered in adults were physiologically insignificant and ran benign clinical courses. Conservative management may thus suffice in this setting if no definitive signs of myocardial ischaemia are evident.
Sinus Hemodynamics Variation with Tilted Transcatheter Aortic Valve Deployments
Leaflet thrombosis is a complication associated with transcatheter aortic valve (TAV) replacement (TAVR) correlated with sinus flow stasis. Sinus hemodynamics are important because they dictate shear stress and washout necessary to avoid stasis on TAV leaflets. Sinus flow is controlled by TAV axial deployment position but little is known regarding TAV axis misalignment effect. This study aims to elucidate TAV angular misalignment with respect to aortic root axis effect on sinus flow stasis potentially leading to leaflet thrombosis. Sinus hemodynamics were assessed in vitro using particle-image velocimetry in three different angular misalignments with respect to aorta axis: untilted, tilted away from the sinus and tilted towards sinus. A 26 mm Edwards SAPIEN3 was implanted in a 3D printed model of an anatomically realistic aortic root. TAV hemodynamics, sinus vortex tracking, leaflet shear stress probability density functions, and sinus blood time to washout were calculated. While pressure gradients differed insignificantly, blood velocity and vorticity decreased significantly in both tilted cases sinuses. Shear stress probability near the leaflet decreases with tilt indicating stasis. TAV tilted away from the sinus is the most unfavorable scenario with poor washout. TAV axial misalignment adds to factors list that could influence leaflet thrombosis risk through modifying sinus hemodynamics and washout.
Potential anatomic substrate of peri-atrioventricular nodal atrial tachycardia ablated from the noncoronary sinus of Valsalva
Introduction Although focal atrial tachycardia (AT) is known to sometimes be ablated from the noncoronary aortic cusp (NCC), the electro-anatomic characteristics of NCC-AT are not well known. Methods We compared the clinical, 12-lead electrocardiogram (ECG), and transthoracic echocardiogram characteristics of 6 women (median age, 66.5 years) with NCC-AT and 12 age-matched women (median age, 64.0 years) with atrioventricular nodal reentrant tachycardia (AVNRT) as the control group. Results There was no difference in the prevalence of hypertension between the two groups (67 vs. 33 %, respectively, P  = 0.3213). The resting ECG of the NCC-AT group vs. that of the AVNRT group showed a significantly longer PQ interval (170.0 (interquartile range (IQR), 157.5–180.0 ms) vs. 140.0 ms (IQR, 122.5–147.5 ms), P  = 0.0010) and leftward shifting of the QRS axis (4° (IQR, −26.0° to 24.0°) vs. 57° (IQR, 43.0–70.2°), P  = 0.0087). The upper interventricular septum (IVS) thickness was significantly greater (15.6 (IQR, 11.9–18.7 ms) vs. 11.7 mm (IQR, 10.2–12.9 ms), P  = 0.0393), and the angle formed by the aortic roof and IVS (AS angle) was significantly steeper (103.0° (IQR, 94.2–119.2°) vs. 122.5° (IQR, 108.5–128.5°), P  = 0.0343) in the NCC-AT group than in the AVNRT group. Conclusions Our data suggest that NCC-AT is characterized by a longer atrioventricular (AV) conduction time, steeper AS angle, and thicker IVS than are seen with AVNRT. These electrocardiographic and echocardiographic characteristics from the IVS to the peri-AV nodal regions may have some effect on the development of NCC-AT.
An unusual cause of cardiac arrest in a young infant
Background Anomalous aortic origin of a coronary artery from the inappropriate sinus of Valsalva (AAOCA) is a rare congenital heart lesion. It is uncommon for patients with AAOCA to present with severe symptoms at a very young age. Case presentation We describe a very rare but critical presentation in a young infant with AAOCA that requires surgical repair and pacemaker placement. A three-month-old infant was referred because of syncope. Cardiac arrest occurred shortly after admission. The electrocardiogram indicated a complete atrioventricular block and a transvenous temporary pacemaker was implanted. A further coronary computed tomographic angiography (CTA) showed the anomalous origin of the right coronary artery from the left sinus of Valsalva. Coronary artery unroofing was performed due to an interarterial course with the intramural component, and a permanent epicardial pacemaker was implanted. The postoperative recovery was uneventful, and this patient was thriving and asymptomatic at the nine-month follow-up. However, the electrocardiogram still indicated a complete pacing rhythm. Conclusions By timely diagnosis and treatment, this patient is successfully rescued. Although rare, AAOCA may be fatal even in infants.
Ruptured sinus of valsalva aneurysm presenting as syncope and hypotension: a case report
Background Unruptured sinus of valsalva aneurysm (SOVA) are typically asymptomatic, and hence can be easily ignored. Ruptured sinus of valsalva aneurysm (RSOVA) usually protrude into the right atrium or ventricular. However, in this case, the RSOVA protruded into the space between the right atrium and the visceral pericardium leading to compression of the right proximal coronary artery. Very few such cases have been reported till date. Case presentation We describe a case of ruptured right SOVA in a 61-year-old man with syncope and persistent hypotension. At the beginning, considered the markedly elevated troponin, acute myocardial infarction was considered. However, emergency coronary angiography unexpectedly revealed a large external mass compressed right coronary artery (RCA) resulting in severe proximal stenosis. Then, aorta computed tomography angiography (CTA) and urgent surgery confirmed that the ruptured right SOVA led to external compression of the right proximal coronary artery. Finally, ruptured right SOVA repair and RCA reconstruction were successfully performed, and the patient was discharged with no residual symptoms. Conclusions It is very important to be vigilant about the existence of SOVA. RSOVA should be suspected in a patient presenting with acute hemodynamic compromise, and echocardiography should be immediately performed. Moreover, it is very important to achieve dynamic monitoring by using cardiac color ultrasound. Definitive diagnosis often requires cardiac catheterization, and an aortogram should be performed unless endocarditis is suspected.
Quantitative perfusion-CMR is significantly influenced by the placement of the arterial input function
The aim of this study is to provide a systematic assessment of the influence of the position on the arterial input function (AIF) for perfusion quantification. In 39 patients with a wide range of left ventricular function the AIF was determined using a diluted contrast bolus of a cardiac magnetic resonance imaging in three left ventricular levels (basal, mid, apex) as well as aortic sinus (AoS). Time to peak signal intensities, baseline corrected peak signal intensity and upslopes were determined and compared to those obtained in the AoS. The error induced by sampling the AIF in a position different to the AoS was determined by Fermi deconvolution. The time to peak signal intensity was strongly correlated (r2 > 0.9) for all positions with a systematic earlier arrival in the basal (− 2153 ± 818 ms), the mid (− 1429 ± 928 ms) and the apical slice (− 450 ± 739 ms) relative to the AoS (all p < 0.001). Peak signal intensity as well as upslopes were strongly correlated (r2 > 0.9 for both) for all positions with a systematic overestimation in all positions relative to the AoS (all p < 0.001 and all p < 0.05). Differences between the positions were more pronounced for patients with reduced ejection fraction. The error of averaged MBF quantification was 8%, 13% and 27% for the base, mid and apex. The location of the AIF significantly influences core parameters for perfusion quantification with a systematic and ejection fraction dependent error. Full quantification should be based on obtaining the AIF as close as possible to the myocardium to minimize these errors.
Resolution of post-anaesthesia aortic regurgitation by repair of a ruptured sinus of Valsalva aneurysm: 5 case reports
Background Ruptured sinus of Valsalva aneurysm (SVA) is a rare cardiovascular disease in which some patients exhibit aortic valve insufficiency. SVA repair and valve replacement are usually required for treatment. Here, we report 5 cases of ruptured SVA with severe post-anaesthesia aortic regurgitation (AR). To the best of our knowledge, this is the first report of ruptured SVA with severe post-anaesthesia AR. Case presentation: From 2018 to 2020, there were 5 cases of ruptured SVA with severe AR after anaesthesia in our hospital. The main symptoms were palpitation and shortness of breath. Transthoracic echocardiography (TTE) with colour-flow Doppler showed ruptured aortic sinus aneurysms without AR. Post-anaesthesia echocardiography showed severe AR. Direct patch closure of the ruptured aneurysm resolved the left-to-right shunt and AR, and the aortic valve was not replaced. Conclusions Post-anaesthesia AR without obvious structural defects may occur in patients with ruptured SVAs. Valve replacement may not be necessary.