Level Of Pulmonary Artery Bifurcation Research Articles

The Use of the Ascyrus Medical Dissection Stent in Acute Type A Aortic Dissection Repair Reduces Distal Anastomotic New Entry Tear

BackgroundA distal anastomotic new entry tear (DANE) can occur at the time of surgical repair for acute type A aortic dissection (ATAAD). This study aimed to compare the occurrence of DANE following a standard hemiarch repair with that following a hemiarch repair with an uncovered arch dissection stent. MethodsAll patients who received a hemiarch repair or a hemiarch repair with an Ascyrus Medical Dissection Stent (AMDS) for ATAAD from 2017 to 2021 were included. Baseline and intra- and postoperative characteristics were collected. All available pre- and postoperative computed tomographic scans were analysed. The primary outcome measures were the incidence of DANE, positive aortic remodelling, mortality, and aortic reintervention rates at last follow-up. ResultsA total of 114 patients underwent repair of Debakey I ATAAD during the study period with either an isolated hemiarch (n = 77) or a hemiarch with AMDS (n = 37). There was no significant difference in mortality (P = 0.768) or other in-hospital adverse events. During the follow-up period, DANE occurred in 43.3% (n = 26) of the isolated hemiarch group and in 11.8% (n = 4) of the hemiarch with AMDS group (P = 0.002). The incidence of false lumen thrombosis and obliteration favoured the AMDS group in the aortic arch (P = 0.029), the proximal descending thoracic aorta (P = 0.031), and level of pulmonary artery bifurcation (P = 0.044). ConclusionsThe incidence of DANE is significantly reduced with the addition of an AMDS at the time of hemiarch repair for ATAAD repair. Further follow-up is necessary to identify late aortic complications that may have been prevented by reducing the incidence of postoperative DANE.

AORTIC REMODELLING FOLLOWING HEMIARCH VERSUS EXTENDED ARCH REPAIR FOR ACUTE TYPE A AORTIC DISSECTION

AORTIC REMODELLING FOLLOWING HEMIARCH VERSUS EXTENDED ARCH REPAIR FOR ACUTE TYPE A AORTIC DISSECTION

Quantitative assessment of velocity and flow using compressed SENSE in children and young adults with adequate acquired temporal resolution

BackgroundPhase contrast (PC) cardiovascular magnetic resonance (CMR) imaging with parallel imaging acceleration is established and validated for measuring velocity and flow. However, additional acceleration to further shorten acquisition times would be beneficial in patients with complex vasculature who need multiple PC-CMR measurements, especially pediatric patients with higher heart rates.MethodsPC-CMR images acquired with compressed sensitivity encoding (C-SENSE) factors of 3 to 6 and standard of care PC-CMR with sensitivity encoding (SENSE) factor of 2 (S2) acquired as part of clinical CMR examinations performed between November 2020 and January 2021 were analyzed retrospectively. The velocity and flow through the ascending aorta (AAo), descending aorta (DAo), and superior vena cava (SVC) in a transverse plane at the level of pulmonary artery bifurcation were compared. Additionally, frequency power distribution and dynamic time warp distance were calculated for these acquisitions. To further validate the adequate temporal resolution requirement, patients with S2 PC-CMR in the same acquisition plane were added in frequency power distribution analysis.ResultsTwenty-eight patients (25 males; 15.9 ± 1.9 years; body surface area (BSA) 1.7 ± 0.2 m2; heart rate 81 ± 16 bpm) underwent all five PC-CMR acquisitions during the study period. An additional 22 patients (16 males; 17.5 ± 7.7 years; BSA 1.6 ± 0.5 m2; heart rate 91 ± 16 bpm) were included for frequency power spectrum analysis. As expected, scan time decreased with increasing C-SENSE acceleration factor = 3 (37.5 ± 6.5 s, 26.4 ± 7.6%), 4 (28.1 ± 4.9 s, 44.7 ± 5.6%), 5 (21.6 ± 3.6 s, 57.6 ± 4.4%), and 6 (19.1 ± 3.2 s, 62.3 ± 4.2%) relative to SENSE = 2 (51.3 ± 10.1 s) PC-CMR acquisition. Mean peak velocity, net flow, and cardiac output were comparable (p > 0.87) between the five PC-CMR acquisitions with mean differences less than < 4%, < 2%, and < 3% respectively. All individual blood vessels showed a non-significant dependence of difference in fmax99 (< 4 Hz, p > 0.2), and dynamic time warp distance (p > 0.3) on the C-SENSE acceleration factor used. There was a strongly correlated (r = 0.74) increase in fmax99 (10.5 ± 2.2, range: 7.1–16.4 Hz) with increasing heart rate. The computed minimum required cardiac phase number was 15 ± 2.0 (range: 11–20) over the heart rate of 86 ± 15 bpm (range: 58–113 bpm).ConclusionsStroke volume, cardiac output, and mean peak velocity measurements using PC-CMR with C-SENSE of up to 6 agree with measurements by standard of care PC-CMR with SENSE = 2 and resulted in up to a 65% reduction in acquisition time. Adequate temporal sampling can be ensured by acquiring 20 cardiac phases throughout the entire cardiac cycle over a wide range of pediatric and young adult heart rates.

P961 Diagnostic use of proportion between ascending aorta and left atrium in patients referred for coronary artery calcium scoring

Abstract Background Non-contrast-enhanced cardiac computed tomography (NCE-CCT) is currently used for coronary artery calcium (CAC) scoring. Meanwhile, other cardiac, vascular and extra-cardiac structures can be evaluated. Data about ascending aorta (AA) and left atrium (LA) has been quantified separately in a few studies. Their mutual proportion has not been examined, as yet. Aim. We hypothesize that mutual proportion between AA and LA size might help for diagnosing their enlargement before absolute cut-off values are reached. Method Among 7950 patients who had NCE-CCT with a 64 raw scanner (Aquillion, Toshiba) within the last decade in our center, in 797 persons the AA diameter (at the level of pulmonary artery bifurcation) and LA diameter and area (highest value) were measured. Raw AAD values were qualified as abnormal if exceeded upper normal limit UNL) for age and height. Weight, BMI and BSA has not been used in order to avoid falsified results in obese patients. The ratio AAD:LAD was quantified as low (&amp;lt;0.8), normal (0.8-1.2) and high (&amp;gt;1.2). Results There were 45 patients (5.6%) who had AAD higher than age-height predicted UNL, including 24 patients with a raw AAD &amp;gt;43mm (3.0%). The other 752 has their AAD within limits. The means of AAD were 42.9 ± 3.2mm and 33.6 ± 3.6mm (p &amp;lt; 0.001). LA size differed significantly, both in diameters 38.5 ± 7.4 vs 34.2 ± 5.6mm (p &amp;lt; 0.001) and areas 2138 ± 593 vs 1837 ± 481 mm2 (p &amp;lt; 0.001). Data regarding mutual relationship are shown in the fig.1. It is seen that normal mutual proportion (AOLARel =1) in patients with high AAD means that LAD was also increased (left graph, red open square). In 603 patients with normal AAD corresponded with normal LAD. The AAD:LAD &amp;gt;1.2 in 845 subjects might suggest increased AAD in spite to normal raw diameter. Similar rules were found in respect to the LA area. Conclusions Ascending aorta and left atrium enlargement are infrequently recognized in patients referred to CAC scoring. Mutual proportion between AA and LA size might complement diagnostic approach of their abnormalities.

Measurement of Main Pulmonary Artery Diameter and its Ratio with Ascending Aorta in Indian Population by Multi Detector Computed Tomography

Introduction: An increase in Pulmonary Artery (PA) pressure is associated with an increase in its diameter. Hence, it is necessary to know the normal range of Main Pulmonary Artery Diameter (MPAD). An attempt has been made to know the same among the Indian population. Aim: To determine the normal range of reference values for diameter of Main Pulmonary Artery (MPA) and its relation with Ascending Aorta (AA) in Indian population. Materials and Methods: A prospective cross-sectional study was conducted between October 2018 and September 2019 ((380 males, 120 females) between the age of 30-65 years). Data from the contrast CT scans of thorax of 500 subjects such as those patients with cough under evaluation, suspected lung nodule, chest wall lesions, primary or secondaries in the lung, etc., who visited the Department of Radio-diagnosis, in the Medical College of South India were analysed. Further, healthy population was also defined as those who were free from chronic cardiopulmonary illness in particular with regard to present study, which would affect the diameter of great vessels including that of PA and aorta. MPA and ascending aortic diameters were measured at the level of pulmonary artery bifurcation, viewed at fixed mediastinal window settings. Statistical Package for Social Sciences (SPSS) version 20, inferential statistics like Unpaired-t test were used to test the significant difference for variables between the two groups (males and females). The level of significance was set at 5%. Results: The MPADs of whole population ranged between 15.6-31.6 mm, with mean diameter of 23.08±2.81 mm. Correlation between age and MPAD was statistically significant (p-value &lt;0.001), while sex-specific MPAD was not significant. The mean AA diameter was 27.15±2.6 mm. The mean AA diameter in males was 27.76±3.2 mm, and 26.67±2.0 mm in females with statistical significance (p-value 0.001) between the groups. The diameter ratio of MPA to AA was 0.85. Conclusion: In present study, the normal ranges of diameter of PA and its ratio with AA were defined among Indians. The diameter ratio of MPA to AA appears to be more important, as it tends to normalise the effects of anthropomorphic factors.

Impact of Pulmonary Artery-to-Aorta Ratio by CT on the Clinical Outcome in Heart Failure

Previous studies have indicated that the ratio of pulmonary artery (PA) to ascending aorta (Ao) diameter as measured by computed tomography (PA/Ao) is strongly associated with pulmonary artery pressure. However, the clinical significance of PA/Ao in heart failure (HF) has not been fully characterized. We sought to investigate the prognostic impact of PA/Ao in HF. Based on the prospective registry of patients admitted to our institution due to acute decompensated HF (ADHF), the records of the consecutive 761 patients admitted between 2011 and 2016 were reviewed. Thoracic computed tomography data during the hospital stays were obtained from 447 patients (median 78 (70-84) years of age; male, 62.2%). The diameters of PA and Ao were measured at the level of PA bifurcation. The subjects were divided into the H group (PA/Ao ≥ 1.0) and the L group (PA/Ao < 1.0) according to the PA/Ao values. The cutoff value was derived from receiver operating curve analysis. There were no significant differences in age, sex or body mass index between the H and L groups. The H group was associated with significantly larger left atrial dimension (LAD), higher tricuspid regurgitation peak gradient (TRPG) and E/e' (LAD, H, 48 (42-55) mm vs L, 45 (39-50) mm, P < 0.001; TRPG, H, 34 (26-48) mm Hg vs L, 28 (22-38) mm Hg, P < 0.001; E/e', H, 23.3 (42-55) vs L, 18.4 (13.9-25), P < 0.001). Length of hospital stay was significantly longer in the H group than in the L group (H, 19 (14-32) days vs L, 16 (12-23) days, P < 0.001). In-hospital mortality was significantly higher in the H group compared with the L group (H, 5.4% vs L, 1.2%, P = 0.02). Age, sex, LAD and TRPG were independently associated with PA/Ao. The primary endpoint, defined as the composite of all-cause death and ADHF rehospitalization during a median of 479 days after discharge, was significantly more common in the H group (P < 0.001, log-rank test). PA/Ao was independently associated with the primary endpoint, even after adjusting for the other confounding factors (P = 0.002). PA/Ao is a reliable marker for the prediction of the outcome of patients with ADHF.

YIA-CS2-4 - Pulmonary Artery to Aorta Ratio by CT Can Predict the Clinical Outcome in Acute Decompensated Heart Failure

Background: Although previous studies indicated that the ratio of pulmonary artery (PA) to ascending aorta diameter (PA/Ao) is associated with pulmonary artery pressure, the significance of PA/Ao in heart failure (HF) is not fully investigated. Methods and Results: Among 761 consecutive patients who were admitted to our institution because of acute decompensated HF from 2011 through 2016, thoracic CT data during the hospital stay were obtained from 447 patients (75.8 ± 11.2 years old, male 62.2%). The diameters of PA and aorta were measured at the level of PA bifurcation. Multiple regression analysis revealed that age, gender, left atrial dimension and tricuspid regurgitation pressure gradient (TRPG) were independent determinants of PA/Ao. The subjects were divided into higher (H) and lower (L) PA/Ao groups by the median value (PA/Ao = 0.88). TRPG and LVEF were higher in H than L (H/L, TRPG, 36 ± 19/29 ± 11 mmHg, P < .0001; LVEF, 48 ± 16/45 ± 15 %, P = .04). In-hospital mortality was higher in H than L (H/L, 4%/0%, P = .0002). Kaplan-Meier analysis showed that composite endpoint of all cause death and HF re-hospitalization was significantly higher in H (P = .004, log-rank test). Cox-regression analysis showed that PA/Ao was independently associated with the composite endpoint even after adjusting for age, gender, BMI, LVEF, hemoglobin level, eGFR (P = .003). Conclusions: Increase of PA/Ao is associated with poor clinical outcome in HF.

Multidetector computed tomographic assessment of the normal diameters for the thoracic aorta and pulmonary arteries in infants and children.

Knowledge of the normal size of the thoracic aorta and pulmonary arteries is important regarding the detection of the abnormal and valuable in the treatment of patients with congenital and acquired cardiovascular diseases. To determine the normal diameters of the thoracic vascular structures of pediatric participants on contrast-enhanced multidetector computer tomography (MDCT) scans. Between July 2010 and July 2014, the MDCT examinations obtained from 520 participants (age range, 0-18 years; mean age, 8.49 years ± 5.54 [standard deviation]; male:female ratio, 1.6:1) with normal cardiovascular examinations were retrospectively evaluated. Patients were divided into six groups according to their age. Diameters of the ascending aorta (AA), descending aorta (DA), main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA) were measured. The diameters of the thoracic vascular structures increased with age and the statistical difference among the age groups and genders were significant. The vascular structures in male patients tended to have higher dimensions than female patients. The LPA demonstrated higher mean values than the RPA in each age group. The mean ratio PA (MPA/AA) is 0.93 ± 0.08 for pediatric participants and it is slightly higher in girls compared to boys (0.93 ± 0.07 and 0.92 ± 0.07, respectively). The level of pulmonary artery bifurcation moves caudally with increasing age with thoracal 6 vertebra being the most common for all age groups (53.3%). We believe that the results of our study can serve as a potential reference in differentiating the normal from the abnormal size of the aorta and pulmonary arteries on chest MDCT studies in the pediatric population.

Frequent Dilatation of the Descending Aorta in Children With Hypoplastic Left Heart Syndrome Relates to Decreased Aortic Arch Elasticity.

BackgroundPatients with hypoplastic left heart syndrome after a Norwood operation show dilatation and reduced distensibility of the reconstructed proximal aorta. Cardiac magnetic resonance imaging (CMR) and angiographic examinations indicate that the native descending aorta (DAo) is also dilated, but this has not been studied in detail.Methods and ResultsSeventy‐nine children with hypoplastic left heart syndrome in Fontan circulation (aged 6.3±3.2 years) and 18 control participants (aged 6.8±2.4 years) underwent 3.0‐tesla CMR. Gradient‐echo cine and phase‐contrast imaging was applied to measure cross‐sectional areas (CSAs), distensibility, pulse wave velocity, and the incremental elastic modulus of the thoracic aorta. CSA of the DAo in patients was also compared with published percentiles for aortic CSA. Patients had significantly larger CSA of the DAo at the level of pulmonary artery bifurcation (229.1±97.2 versus 175.7±24.3 mm/m2, P=0.04) and the diaphragm (196.2±66.0 versus 142.6±16.7 mm/m2, P<0.01). In 41 patients (52%), CSA of the DAo was >95th percentile level for control participants, and the incremental elastic modulus of the aortic arch and the DAo was higher than in patients with normal CSAs (arch: 90.1±64.3 versus 45.6±38.9 m/s; DAo: 86.3±53.7 versus 47.1±47.6 m/s; P<0.01). Incremental elastic modulus of the aortic arch and the DAo correlated with the CSA of the DAo (arch: r=0.5; DAo: r=0.49; P<0.01).ConclusionsChildren with hypoplastic left heart syndrome frequently show dilatation of their DAo associated with increased stiffness of the aortic arch. Higher aortic impedance increases the afterload of the systemic circulation and likely contributes to the burden of the systemic right ventricle.

ALTERATION OF ELASTIC PROPERTIES IN CONGENITAL/INHERITED AORTIC DISEASES: MRI STUDY IN MARFAN SYNDROME AND BICUSPID AORTIC VALVE

Marfan Syndrome and Bicuspid Aortic Valve (BAV) are characterized by the congenital/inherited alteration of the fibrillin proteins of aortic wall extracellular matrix, with higher incidence of aortic dissection/rupture even without aortic dilation. Therefore, early identification and treatment of aortic involvement could improve prognosis. The purpose of this study was to evaluate aortic elastic properties of BAV and Marfan Syndrome patients to identify an index of early aortic involvement. Methods: A Magnetic Resonance Imaging (MRI) study was performed on 38 BAV patients, 20 Marfan patients and 14 healthy volunteers as a control group. A high-resolution gradient-echo sequence was applied in the axial plane at the level of pulmonary artery bifurcation to evaluate aortic distensibility. Results: Aortic distensibility was significantly different among the three groups (ANOVA, p = 0.0001) and was sensibly reduced in BAV (0.0056 ± 0.0048 versus 0.025 ± 0.006 control group) and Marfan (0.0085 ± 0.006 versus 0.025 ± 0.006 control group). Intraobserver and interobserver reproducibility for diastolic measurements were 1.2% and 0.4% respectively and for systolic measurements, they were 1.1% and 0.3% respectively. Conclusion: In BAV or Marfan Syndrome patients, MRI evaluation of abnormal distensibility may provide a reliable index of early aortic involvement, even before aortic dilation occurs.