Arterial Flow Patterns Research Articles

Substantive hemodynamic and thermal strain upon completing lower-limb hot-water immersion; comparisons with treadmill running

ABSTRACTExercise induces arterial flow patterns that promote functional and structural adaptations, improving functional capacity and reducing cardiovascular risk. While heat is produced by exercise, local and whole-body passive heating have recently been shown to generate favorable flow profiles and associated vascular adaptations in the upper limb. Flow responses to acute heating in the lower limbs have not yet been assessed, or directly compared to exercise, and other cardiovascular effects of lower-limb heating have not been fully characterized. Lower-limb heating by hot-water immersion (30 min at 42°C, to the waist) was compared to matched-duration treadmill running (65-75% age-predicted heart rate maximum) in 10 healthy, young adult volunteers. Superficial femoral artery shear rate assessed immediately upon completion was increased to a greater extent following immersion (mean ± SD: immersion +252 ± 137% vs. exercise +155 ± 69%, interaction: p = 0.032), while superficial femoral artery flow-mediated dilation was unchanged in either intervention. Immersion increased heart rate to a lower peak than during exercise (immersion +38 ± 3 beats·min-1 vs. exercise +87 ± 3 beats·min-1, interaction: p < 0.001), whereas only immersion reduced mean arterial pressure after exposure (−8 ± 3 mmHg, p = 0.012). Core temperature increased twice as much during immersion as exercise (+1.3 ± 0.4°C vs. +0.6 ± 0.4°C, p < 0.001). These data indicate that acute lower-limb hot-water immersion has potential to induce favorable shear stress patterns and cardiovascular responses within vessels prone to atherosclerosis. Whether repetition of lower-limb heating has long-term beneficial effects in such vasculature remains unexplored.

First-Trimester Echocardiographic Features and Perinatal Outcomes in Fetuses With Congenital Absence of the Aortic Valve.

The purpose of this study was to describe the echocardiographic features and perinatal outcomes of congenital absence of the aortic valve diagnosed by first-trimester echocardiography. This retrospective study assessed the feasibility of first-trimester echocardiography in detecting absence of the aortic valve. All cases of absence of the aortic valve diagnosed by first-trimester fetal echocardiography from January 2010 to December 2014 were identified at a single referral center using an established perinatal database. Demographic information, echocardiograms, perinatal outcomes, and autopsy reports were reviewed. Echocardiographic features were described. A total of 50,822 fetuses underwent first-trimester echocardiography during the study period. Ten cases of congenital absence of the aortic valve were diagnosed, for an overall incidence rate of 0.019%. The earliest gestational age at diagnosis was 11 weeks 6 days. The mean crown-lump length was 61.9 mm; mean gestational age was 12 weeks; and mean maternal body mass index ± SD was 21.2 ± 3.9 kg/m(2). Nine fetuses had increased nuchal translucency ranging from 2.4 to 12.4 mm (mean ± SD, 6.4 ± 3.6 mm). Color Doppler flow imaging revealed biphasic bidirectional flow in the ascending aorta and aortic arch and reversed flow in the ductus venosus during atrial systole in all cases. Reversed diastolic flow was present in the umbilical arteries and thoracic aorta. All cases had complex cardiac malformations as well as extracardiac abnormalities. Our study confirms that absence of the aortic valve is a rare cardiac defect that can be diagnosed by first-trimester fetal echocardiography. A "to-and-fro" flow pattern or biphasic bidirectional flow in the great arteries is a key echocardiographic feature in fetuses with absence of the aortic valve.

Characterization of Hemodynamics in Great Arteries of Wild-Type Mouse Using Computational Fluid Dynamics Based on Ultrasound Images.

Hemodynamic factors in cardiovascular system are hypothesized to play a significant role in causing structural heart development. It is thus important to improve our understanding of velocity characteristics and parameters. We present such a study on wild-type mouse to characterize the vessel geometry, flow pattern, and wall shear stress in great arteries. Microultrasound imaging for small animals was used to measure blood boundary and velocity of the great arteries. Subsequently, specimens' flow boundary conditions were used for 3-dimensional reconstructions of the great artery and aortic arch dimensions, and blood flow velocity data were input into subject-specific computational fluid dynamics for modeling hemodynamics. Measurement by microultrasound imaging showed that blood velocities in the great artery and aortic arch had strong correlations with vascular sizes, whereas blood pressure had a weak trend in relation to vascular size. Wall shear stress magnitude increased when closer to arterial branches and reduced proximally in the aortic root and distally in the descending aorta, and the parameters were related to the fluid mechanics in branches in some degree. We developed a method to investigate fluid mechanics in mouse arteries, using a combination of microultrasound and computational fluid dynamics, and demonstrated its ability to reveal detailed geometric, kinematic, and fluid mechanics parameters.

Evaluation of cerebrovascular reserve in patients undergoing carotid artery stenting and its usefulness in predicting significant hemodynamic changes during temporary carotid occlusion.

We investigated the usefulness of cerebrovascular reserve (CVR) testing to predict severe hemodynamic changes during proximally protected carotid artery stenting. Of 90 patients referred, 63 eligible underwent complete evaluation of the extent of carotid artery disease and transcranial Doppler ultrasound (TCD) assessment of CVR by means of a breath-holding test and ophthalmic artery flow pattern evaluation. Periprocedural TCD monitoring of the ipsilateral middle cerebral artery flow was performed in 24 patients undergoing proximally protected procedure (requiring induction of flow arrest within internal carotid artery). Abnormal CVR was significantly less common in patients with unilateral compared to bilateral carotid artery disease (26.3 % vs. 76.9 %, p=0.02), while ophthalmic artery flow reversal was rare in patients with unilateral carotid artery disease (2.5 % vs. 42.9 %, p<0.01). During the induction of carotid flow arrest, the average mean flow velocity drop following external carotid artery occlusion was low (3.5 %, p=0.67) compared to the induction of complete flow arrest (32.8 %, p<0.01). Six patients had a total mean flow velocity drop >50 %, including 2 patients with normal pre-procedural CVR. Our results suggest that TCD evaluation of CVR is not a reliable predictor of hemodynamic changes induced during proximally protected carotid artery stenting in patients with unilateral carotid artery disease.

Color Doppler and pulse wave assessment of flow in anomalous origin of left coronary artery from pulmonary artery: Pre- and post-surgery.

Changes in left coronary artery flow pattern in anomalous left coronary from pulmonary artery can provide valuable insight into pathology and natural history of disease. We wish to discuss a case with pre and post operative left coronary flow pattern with mid term follow up.

A comprehensive study on radial artery patency and flow pattern after transradial coronary intervention

A comprehensive study on radial artery patency and flow pattern after transradial coronary intervention

Prediction of Neonatal Outcome by Umbilical Artery Velocimetry in Intrauterine Growth Restriction: A Study in Western Nepal

The introduction of Doppler velocimetry to obstetrics offered a noninvasive and safe imaging modality of indirectly assessing the fetal and uteroplacental circulation. Obstetric Doppler ultrasound plays an important role in detecting Intra Uterine Growth Restriction (IUGR). The early diagnosis of IUGR with the help of abnormal flow patterns in umbilical, uterine and middle cerebral arteries using Doppler ultrasound may help in reducing perinatal and neonatal mortality and morbidity as well as reducing perinatal complications. This provides for timely interventions to prevent progression from IUGR to Intrauterine death (IUD).The study was carried out in 140 patients in Manipal Teaching Hospital, Pokhara for a period of twenty months from October 2013 to June 2015. All the cases presented to Radiology department for obstetric Doppler with clinical suspicion of IUGR were taken up for the study and obstetric doppler of umbilical artery was performed. Seventy two out of 140 (51.50%) had abnormal umbilical artery Doppler velocimetry. Fifty seven out of these 72 subjects (positive predictive value – 79.2%) with abnormal umbilical artery Doppler were later born with small for gestational age (SGA). The S/D ratio of umbilical artery of 3 or greater was considered abnormal in predicting IUGR and it showed sensitivity, specificity, positive predictive value, and negative predictive value of 76%, 76.9%, 79.2% and 73.5% respectively. Admission to the Neonatal Intensive Care Unit (NICU) and incidence of perinatal and neonatal mortality increased with the worsening of Doppler velocimetry. Twenty seven out of one hundred and forty neonates developed perinatal asphyxia, out of which 26 (96.3%) had abnormal umbilical artery velocimetry. NICU admissions comprised of a total of 30 neonates, out of which 27(90%) had abnormal umbilical artery Doppler velocimetry prenatally. Fifteen out of thirty didn’t survive, all of whom had abnormal umbilical artery Doppler velocimetry prenatally. There were 3 still born and all of them had abnormal umbilical artery velocimetry prenatally. The study could underline that abnormal Doppler velocimetry has a fairly good sensitivity and specificity for predicting IUGR and it is related with poor neonatal outcomes.

Spiral blood flow in aorta–renal bifurcation models

The presence of a spiral arterial blood flow pattern in humans has been widely accepted. It is believed that this spiral component of the blood flow alters arterial haemodynamics in both positive and negative ways. The purpose of this study was to determine the effect of spiral flow on haemodynamic changes in aorta–renal bifurcations. In this regard, a computational fluid dynamics analysis of pulsatile blood flow was performed in two idealised models of aorta–renal bifurcations with and without flow diverter. The results show that the spirality effect causes a substantial variation in blood velocity distribution, while causing only slight changes in fluid shear stress patterns. The dominant observed effect of spiral flow is on turbulent kinetic energy and flow recirculation zones. As spiral flow intensity increases, the rate of turbulent kinetic energy production decreases, reducing the region of potential damage to red blood cells and endothelial cells. Furthermore, the recirculation zones which form on the cranial sides of the aorta and renal artery shrink in size in the presence of spirality effect; this may lower the rate of atherosclerosis development and progression in the aorta–renal bifurcation. These results indicate that the spiral nature of blood flow has atheroprotective effects in renal arteries and should be taken into consideration in analyses of the aorta and renal arteries.

Increased Umbilical Artery Pulsatility Index in Third-Trimester Fetuses with Trisomy 21

Objective: To examine the umbilical arterial Doppler flow patterns in late third-trimester fetuses with trisomy 21. Methods: This is a retrospective study on fetuses with trisomy 21 that were evaluated after 33 weeks' gestation at the Department of Obstetrics and Gynaecology of the University of Tuebingen, Germany. The umbilical and the middle cerebral artery (UA and ACM) pulsatility index (PI) measurements and the abdominal circumference were transformed into z-values. Results: Forty-two fetuses met the study criteria. The mean gestational age at the time of the first and the second visit was 35.0 and 36.6 weeks, respectively. The mean UA PI was 1.31 and 1.38, which corresponds to z-values of 2.20 and 2.70. In 24 (57.1%) cases, both PI measurements were above the 95th centile. A linear regression analysis demonstrated that the mean of both UA PI was not dependent on the abdominal circumference or on any other examined maternal and pregnancy characteristics. The mean ACM PI at the first and the second visit was 1.62 and 1.48, respectively, corresponding to mean z-values of -0.59 and -0.75, and in none of the cases was it below the 5th centile. Conclusion: In half of the third-trimester fetuses with trisomy 21, the resistance in the UA is increased - even in the absence of placental insufficiency.

Surgical technique for the implantation of tissue engineered vascular grafts and subsequent in vivo monitoring.

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large animal model. A step by-step protocol for inter-positional placement of the TEV and real-time digital assessment of the TEV and native carotid arteries is described here. In vivo monitoring is made possible by the implantation of flow probes, catheters and ultrasonic crystals (capable of recording dynamic diameter changes of implanted TEVs and native carotid arteries) at the time of surgery. Once implanted, researchers can calculate arterial blood flow patterns, invasive blood pressure and artery diameter yielding parameters such as pulse wave velocity, augmentation index, pulse pressures and compliance. Data acquisition is accomplished using a single computer program for analysis throughout the duration of the experiment. Such invaluable data provides insight into TEV matrix remodeling, its resemblance to native/sham controls and overall TEV performance in vivo.

Surgical Technique for the Implantation of Tissue Engineered Vascular Grafts and Subsequent &lt;em&gt;In Vivo &lt;/em&gt;Monitoring

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large animal model. A step by-step protocol for inter-positional placement of the TEV and real-time digital assessment of the TEV and native carotid arteries is described here. In vivo monitoring is made possible by the implantation of flow probes, catheters and ultrasonic crystals (capable of recording dynamic diameter changes of implanted TEVs and native carotid arteries) at the time of surgery. Once implanted, researchers can calculate arterial blood flow patterns, invasive blood pressure and artery diameter yielding parameters such as pulse wave velocity, augmentation index, pulse pressures and compliance. Data acquisition is accomplished using a single computer program for analysis throughout the duration of the experiment. Such invaluable data provides insight into TEV matrix remodeling, its resemblance to native/sham controls and overall TEV performance in vivo.

Echocardiographic Assessment of Pulmonary Arteries Pulsatility Index in Fontan Circulation.

BackgroundLate complications after Fontan procedure may be due to the absence of pump and pulsatile pulmonary blood flow in this type of palliation. Our aim was to quantify the degree of pulsation by echocardiographic method in patients with extracardiac total cavopulmonary connection (ECTCPC) in comparison with biventricular circulation and few cases of pulsatile Fontan.MethodsIn a case series study, pulsatility index (PI) derived by echocardiographic method were compared between 20 patients with ECTCPC, 6 patients with pulsatile Fontan and 18 normal individual aged 4 to 20 years old. All patients were in New York Heart Association class of I and there was no report of complication.ResultsIn patients with ECTCPC pulmonary artery branches Doppler flow study showed lower peak and mean velocities compared to the pulsatile Fontan and normal groups. ECTCPC patients had PI of 0.59 ± 0.14 and 0.59 ± 0.09 for right and left pulmonary arteries (RPA and LPA) respectively. PI was higher in patients with preserved antegrade flow (RPA PI = 0.94 ± 0.26, LPA PI = 0.98 ± 0.27) and in normal individuals (RPA PI = 1.59 ± 0.12, LPA PI = 1.64 ± 0.17) for both branches (p = 0.000).ConclusionUsing a Doppler derived index for pulsatility, patients with ECTCPC had the least pulsation. The pulmonary artery flow pattern in patients with preserved antegrade flow showed higher pulsatility indices in both branches. Normal individuals had the greatest pulsatility index.

Retrograde shear rate in formerly preeclamptic and healthy women before and after exercise training: relationship with endothelial function

Blood flow patterns in conduit arteries characterized by high levels of retrograde shear stress can be detrimental for vascular health. In this study we examined whether retrograde shear rate and endothelial function are related in healthy and formerly preeclamptic (PE) women and whether this relationship is altered by exercise training. Formerly PE women (32 ± 4 yr, n = 20) and controls (32 ± 4 yr, n = 20), all 6-12 mo postpartum, performed 12-wk aerobic exercise training. We measured brachial artery shear rate (SR) and endothelial function by flow-mediated dilation (FMD, echo-Doppler). We additionally performed power spectral analysis of heart rate variability and calculated low-frequency/high-frequency (LF/HF) ratio. Antegrade SR was not different between groups, while retrograde SR was significantly higher and FMD% lower in PE women compared with controls (both P < 0.05). Retrograde shear correlated strongly with FMD% in PE women and controls (P < 0.05). LF/HF ratio inversely correlated with brachial artery retrograde SR and FMD% (both P < 0.05) in PE women and controls. Exercise training reduced retrograde shear, improved FMD%, and reduced LF/HF ratios similarly in both groups (all P < 0.05). Training-induced changes in retrograde SR correlated with changes in FMD% and LF/HF ratio. A higher brachial artery retrograde SR relates to lower brachial artery endothelial function, in both controls and formerly PE women. Exercise training improves retrograde SR, while the magnitude of this change correlated strongly with improvements in FMD and reductions in LF/HF ratio. Therefore, the impact of PE and exercise training on endothelial health may, at least partly, be related to retrograde shear rate.

Effect of Carotid Artery Stenting on Ophthalmic Artery Flow Patterns

The purpose of this study was to assess the effect of carotid artery stenting on ophthalmic artery blood flow using transorbital color and spectral Doppler sonography and review the changes in relation to cerebral hemodynamics. Twenty-eight consecutive patients with severe internal carotid artery stenosis (≥ 70%) who were scheduled for carotid stenting were included. Ophthalmic artery Doppler sonography was performed bilaterally before and after stenting. The flow direction, peak systolic velocity (PSV), end-diastolic velocity (EDV), pulsatility index (PI), and resistive index in the ophthalmic artery were recorded. Twenty male and 8 female patients with 10 right-sided and 18 left-sided stenoses were studied. The mean overall carotid stenosis ratio ± SD was 87.3% ± 9.9%. After stenting in the ophthalmic artery ipsilateral to the stenosis, significant increases in the PSV (-3.87 ± 48.81 to 46.70 ± 25.33 cm/s; P < .001), and EDV (-3.02 ± 16.31 to 11.24 ± 7.37 cm/s; P < .001) were detected, and the increase in the PI approached significance (1.40 ± 0.59 to 1.62 ± 0.52; P = .055). A change in the flow direction from retrograde to antegrade was noted in 11 patients (39%) after stenting, and in 1 patient with no detectable flow, reconstitution of flow was observed. Increases in the PSV and EDV (P= .03 for ΔEDV) were more pronounced in symptomatic patients than asymptomatic patients after stenting. Substantially decreased ophthalmic artery velocity and retrograde flow are suggestive of high-grade carotid artery stenosis (≳90%). Stenting improves ophthalmic artery perfusion and positively changes cerebral hemodynamics in high-grade carotid artery stenosis, especially in symptomatic patients, which can be monitored with ophthalmic artery Doppler sonography.

Thermodynamic energy stability and in vitro potassium exchange capacity of ZS-9, a novel selective cation trap for the treatment of hyperkalemia

divided into four subgroups: Group 1: received s.c. injection of phosphate buffered saline; Group 2: received s.c. injection of MCT (MCT alone); Group 3: received injection of MCT followed by i.v. transfusion of rat PAECs transduced with empty adenoviral vector (Null-EC); and Group 4: received injection of MCT followed by i.v. transfusion of rat PAECs overexpressing IL8RA and RB (IL8RA/RB-EC, total 0.5x10 cells/rat). Two days or 4 wks after MCT treatment, eNOS, iNOS, IL-8 (Cinc-2b in rat) and MCP-1 expression and neutrophil and macrophage infiltration in pulmonary arterioles and alveoli, as well as pulmonary arterial flow pattern and arteriole hypertrophy were measured by histological, immunohistochemical staining and echocardiography, respectively. Results: Compared to the MCT alone and MCT-Null-EC groups, transfusion of IL8RA/RB-ECs significantly decreased MCT-induced neutrophil infiltration and pro-inflammatory mediator expression in pulmonary arterioles and alveoli, reduced pulmonary vascular and RV hypertrophy and remodeling. Conclusion: These provocative findings suggest that targeted delivery of PAECs overexpressing IL8RA and IL8RB is effective in repairing injured pulmonary vasculature. Targeted delivery of PAECs to injured lungs provides a novel strategy for the treatment of pulmonary vascular injury in humans.

Fluid-structure interaction investigation of spiral flow in a model of abdominal aortic aneurysm

The presence of a spiral arterial blood flow pattern in both animals and humans has been widely accepted. The effect of spiral flow on physiological processes associated with abdominal aortic aneurysm (AAA) development and progressions can provide valuable information. The purpose of this study is to investigate the influence of spiral flow on haemodynamic changes in an elastic AAA model by implementing a coupled fluid–structure interaction (FSI) analysis. The results showed that an increase in the intensity of spiral flow resulted in an increase in maximum wall shear stress (WSS) and a decrease in maximum wall stress; however, the spiral flow effect on the WSS was higher than the wall stress. It was also shown that not taking into consideration the effect of spiral flow in modelling of AAA can underestimate the magnitude of WSS by up to 30% and overestimate the magnitude of wall stress by up to 11%. The presence of spiral flow within AAAs is associated with beneficial and detrimental effects. The beneficial effects are to reduce the wall stress and the size of regions with low WSS which in turn reduce the risk of rupture, endothelial dysfunction and the development of atherosclerosis. However, the increase in magnitude of WSS is seen as the detrimental effect of spiral flow.

Restricted blood flow in the abdominal aorta at rest and exercise in patients after coarctation aortae repair despite correction

Purpose: Anatomic measurements and blood pressure differences in rest are currently used to determine whether patients after aortic repair for coarctation have a recoarctation or not. Whether flow patterns in the abdominal aorta at rest and during exercise are of additional value in determining functional restriction of the former coarctation side is unknown. Therefore, we investigated Doppler flow patterns in the abdominal aorta compared these with normal volunteers. Methods: We included random patients after aortic coarctation repair without significant re-coarctation on MRI, or uncontrolled hypertension. All patients underwent a rest echocardiography and a bicycle exercise test with echocardiographic examination limited to 70% of the predicted heart rate. Echocardiography was performed according to international recommendations. The systolic diastolic ratio (S/D) was measured in the abdominal aorta. The pulse delay was the difference of the time measured from R-wave until peak velocity in the left ventricular outflow tract and the abdominal aorta. Ten random healthy volunteered controls underwent the similar protocol. Results: Twenty adult patients were included (10 males, mean age 38 years±5) and 10 healthy controls (4 males, mean age 41 years± 10). The maximum flow velocity in the descending aorta was significantly higher than in healthy volunteers. The S/D ratio at rest was similar for both patient groups, but differed significantly at exercise. The pulse delay was significantly larger in coarctation patients than in controls. All parameters indicate a abnormal arterial systemic flow pattern below the coarctation site. View this table: Conclusion: Patients after coarctation without clinical recoarctation have very abnormal flow patterns in the post coarctation aorta, especially during exercise. Further research is needed to determine whether this is clinical meaningful and whether other definitions of recoarctation should be formulized.

USCOM—window to the circulation: utility of supra-sternal Doppler in an elderly anaesthetized patient for a robotic cystectomy

Supra-sternal Doppler (USCOM Ltd., Sydney, Australia) can be used during anaesthesia to measure cardiac output (CO) and related flow parameters. However, before the USCOM can be used routinely, its utility and limitations need to be fully understood and critical information about its use disseminated. In "Window to the Circulation" we use the example of an elderly man undergoing major urological robotic surgery to highlight the utility and limitations of intra-operative USCOM use. USCOM readings were verified against oesophageal Doppler. Despite the lack of major blood loss (<500 ml in 8-h), significant changes in haemodynamics were recorded. CO ranged from 3.2 to 8.3 l/min. The quality of USCOM scans and reliability of data was initially poor, but improved as CO increased as surgery progressed. When USCOM scans became acceptable the correlation with oesophageal Doppler was R(2) = 8.0 (p < 0.001). Several characteristic features of the supra-sternal Doppler scans were identified: Aortic and pulmonary flow waves, valve closure, E and A waves, false A-wave and aberrant arterial flow patterns. Their identification helped with identifying the main flow signal across the aortic valve. The USCOM has the potential to monitor changes in CO and related flow parameters intra-operatively and thus help the anaesthetist to more fully understand the patient's haemodynamics. However, achieving a good quality scan is important as it improves the reliability of USCOM data. The supra-sternal route is rich in flow signals and identifying the aortic valve signal is paramount. Recognizing the other characteristic waveforms in the signal helps greatly.

Hemodynamic Changes in Left Anterior Descending Coronary Artery and Anterior Interventricular Vein during Right Ventricular Apical Pacing: A Doppler Ultrasound Study in Open Chest Beagles

ObjectiveThe aim of this study was to quantify the effects of right ventricular apical pacing (RVAP) on hemodynamics in left anterior descending coronary artery (LAD) and anterior interventricular vein (AIV) contrast to baseline condition in open chest beagles using Doppler ultrasound imaging.MethodsIn 6 anesthetized open chest beagles, the spectral Doppler waveforms of the middle segmental LAD and the AIV were acquired with a 5 MHz linear array transducer at baseline condition and during RVAP. The aortic pressure-time curves were recorded synchronously. The Doppler hemodynamic parameters of the LAD and AIV at both states were derived and compared.ResultsThe spectral Doppler waveforms of the LAD had a principal diastolic positive wave (Dp), which heelled by a momentary negative wave and a positive wave during early systole at baseline condition. During RVAP, an additional negative wave appeared in the LAD at late systole. The duration of the Dp shortened (227.83±12.16 ms vs 188.50±8.97 ms, P<0.001), and the acceleration of the Dp decreased (11.85±2.22 m/s2 vs 3.54±0.42 m/s2, P<0.001). The spectral Doppler waveforms of the AIV only had a principal positive wave (Sp) at baseline condition, but an additional diastolic negative wave appeared during RVAP. The duration of the Sp shortened (242.99±7.98 ms vs 215.38±15.44 ms, P<0.001), and the acceleration of the Sp decreased (9.61±1.93 m/s2 vs 1.01±0.11 m/s2, P<0.001).ConclusionsObvious hemodynamic changes in the LAD and AIV during RVAP were observed, and these abnormal flow patterns in epicardial coronary arteries and vena coronaria may be sensitive and important hints of the disturbed cardiac electrical and mechanical activity sequences.

Recurrent coronary artery thrombosis after anomalous right coronary artery re‐implantation to the aorta

Anomalous origin of the right coronary artery (RCA) from the pulmonary artery is a rare entity. The current recommendation is corrective operation even in asymptomatic patients when this cardiac malformation is found. We report a case of a 21-year-old male who initially presented with ST elevations. After surgical repair with re-implantation of the RCA to the aorta, he was found to have an acute thrombus in his left circumflex and several months later developed a thrombus in the proximal left anterior descending artery. We propose that the change from a hyperkinetic high flow state to a slow flow state in the setting of inadequate coronary flow reserve and endothelial function predisposed our patient to thrombus formation in the persistently dilated coronary arteries. It is expected that restoration of normal flow pattern in all coronary arteries will result in normalization of perfusion, decrease in feeding artery size, and return of endothelial function. Because this anomaly is rare, limited information exists on the effects of the procedure on myocardial perfusion. These findings raise the question of whether re-implantation of the anomalous artery is truly the superior approach.