Ostial Diameter Research Articles

Reconstructing and Registering Three‐Dimensional Rotational Angiogram of Left Atrium during Ablation of Atrial Fibrillation

Three-dimensional (3D) image of left atrium (LA) can greatly facilitate ablation of atrial fibrillation (AF). Reconstructing method using computed tomography (CT) has certain limitations. The 3D image of LA can be intraprocedurally reconstructed by a rotational angiography technique. Forty-six patients undergoing AF ablation were included in this study. Preprocedural CT imaging and intraprocedural reconstructing 3D rotational angiogram (3DRA) of LA were performed in all the patients. Rapid ventricular pacing (RVP, 300 ms) was used to inhibit the drainage of atrium. During RVP, contrast medium was injected into the LA, and rotational angiography was performed. The 3DRA was reconstructed and was registered with the live fluoroscopy. The 3DRA was evaluated in comparison to the CT image. In the navigation of the registered 3DRA, the ablation of AF was performed. Forty-four 3DRAs (95.7%) were successfully reconstructed and registered with the live fluoroscopy. The LA anatomy was delineated in the 3DRA in comparison to a CT image. AF ablation was successfully performed in the 44 patients in the navigation of the registered 3DRA. There were good correlations in the PV ostial diameter and the LA volume as assessed by 3DRA in comparison to a CT image (r>=0.87). The radiation exposure in rotational angiography was substantially less than that in CT scanning (2.7+/-0.9 mSv vs. 24.9+/-3.1 mSv, P<0.001). It is feasible to reconstruct and register the 3DRA with live fluoroscopy using the RVP method during the ablation of AF.

Magnetic Resonance Imaging Versus Computed Tomography for Characterization of Pulmonary Vein Morphology Before Radiofrequency Catheter Ablation of Atrial Fibrillation

The accurate assessment of pulmonary vein (PV) anatomy is important in planning radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). The aim of the present study was to perform a head-to-head comparison of magnetic resonance imaging (MRI) and multislice computed tomography (CT) for the evaluation of PV morphology before RFCA of AF. Contrast-enhanced MRI (on a 1.5-T system) and multislice CT (on a dual-source system) were performed for the evaluation of the PVs in 44 consecutive patients (31 men, mean age 56 +/- 10 years) admitted for RFCA of drug-refractory AF. Data on PV anatomy, ostial branching pattern, and ostial dimensions were compared between MRI and multislice CT. Variant PV anatomy was observed in 21 patients (48%) with the 2 imaging approaches. The incidence of PV ostial branching, as assessed with MRI and multislice CT, was higher on the right and more common in the inferior than superior vein. Agreement between the 2 imaging modalities for the evaluation of variant PV anatomy (kappa = 0.87, 95% confidence interval 0.77 to 0.97) and ostial branching pattern (kappa = 0.84, 95% confidence interval 0.75 to 0.93) was nearly perfect. Assessment of PV ostial cross-sectional area as well as maximal and minimal ostial diameters resulted in strong agreement and correlation (r(2) = 0.75 to 0.99, p <0.001 for all) between the 2 imaging approaches. In conclusion, MRI and multislice CT of the PVs appear to provide similar and detailed anatomic and quantitative information before RFCA of AF.

Three-Dimensional Imaging of Pulmonary Veins by a Novel Steady-State Free-Precession Magnetic Resonance Angiography Technique Without the Use of Intravenous Contrast Agent

To evaluate the feasibility of 3-dimensional (3D) steady-state free-precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation for imaging of pulmonary veins (PVs) without intravenous gadolinium chelate and to correlate the results with conventional contrast-enhanced MRA (CE-MRA). Forty consecutive patients with history of atrial fibrillation underwent free-breathing respiratory navigator-gated electrocardiogram-triggered SSFP MRA without contrast administration and conventional high-resolution 3D CE-MRA of the thorax at 1.5 T. Two readers assessed both datasets for vascular definition (from 0, not visualized, to 3, excellent definition), artifacts, and ostial diameters. Statistical analysis was performed using Wilcoxon, paired t test, and kappa coefficient. On SSFP MRA, readers 1 and 2 graded 96.4% (160/166) and 97% (161/166) of the segments as having diagnostic visibility and sharpness, respectively (k = 0.82). On CE-MRA datasets, all segments were graded as having diagnostic visibility and sharpness by both readers (k = 0.86). No significant difference existed for visibility and sharpness of pulmonary venous segments between the datasets for each reader (P[r] > 0.05). Reader 1 (2) identified 27 (28) and 35 (32) motion artifacts on SSFP and CE-MRA datasets, respectively. No significant difference was found to exist between ostial diameters on CE-MRA and SSFP datasets (P > 0.05). Our study shows that 3D depiction of PVs without intravenous contrast is feasible with nonslice-selective SSFP MRA. This novel MRA technique may be used in certain patients with atrial fibrillation to assess the number and size of PV ostia draining to the left atrium prior to radiofrequency ablation.

Rapid ventricular pacing to optimize rotational angiography in atrial fibrillation ablation

Conventional pulmonary vein (PV) angiography cannot precisely delineate the left atrium (LA)-PV anatomy, which is essential for the ablation of atrial fibrillation (AF). The aim of the study was to test the feasibility of a novel method of rotational angiography for the AF ablation. Forty-one patients were enrolled in this study. CT scanning was performed in all patients before the procedure. Rotational angiography (rotating from right anterior oblique 55 degrees to left anterior oblique 55 degrees ) was performed before AF ablation. Rapid ventricular pacing (RVP, 300 ms) was carried out to reduce cardiac output while contrast medium was injected into the LA via a pigtail catheter. RVP was successfully performed in 36 (87.8%) patients. The ostia of all PVs and the LA appendage were visible in all these 36 cases. There was a good correlation in the PV ostial diameters as assessed by rotational angiography via RVP as compared to CT imaging (r (2) > 0.85). Rotational angiography by RVP is able to delineate the LA-PV anatomy. There is a good correlation in the PV ostial diameters as assessed by rotational angiography via RVP and CT imaging. Rotational angiography by RVP is feasible during AF ablation.

Assessment of left main coronary artery atherosclerotic burden using 64-slice CT coronary angiography: correlation between dimensions and presence of plaques

The aim of this study was to correlate left main (LM) coronary artery dimensions with the presence of atherosclerosis by multidetector-row computed tomography (MDCT) coronary angiography (CA) and to assess coronary atherosclerotic plaques with a semiquantitative method. Sixty-two consecutive patients (41 men, mean age 60+/-11) with suspected coronary artery disease underwent 64-MDCT coronary angiography. LM dimensions (length, ostial and bifurcation diameters), quantitative [location, Hounsfield unit (HU) attenuation] and qualitative (composition, shape) analysis of plaques within the LM were performed. All patients underwent conventional CA. Thirty patients (mean age 55+/-10) without plaques in the LM presented the following average dimensions: length 10.6+/-6.1 mm, ostial diameter 5.5+/-0.7 mm, bifurcation diameter 4.9+/-0.9 mm. LM plaques (n=36) were detected in 32 patients (mean age 64+/-10) with the following LM average dimensions: length 11.3+/-4.0 mm, ostial diameter 6.0+/-1.2 mm and bifurcation diameter 6.0+/-1.2 mm. Plaques were calcified (40%, mean attenuation 742+/-191 HU), mixed (43%, mean attenuation 387+/-94 HU) or noncalcified (17%, mean attenuation 56+/-14 HU) and were frequently eccentric (77%). Age was significantly different in the two groups (p<0.05). LM diameters of patients with plaques were improved (p<0.05). A moderate correlation was found between the LM bifurcation diameter and the corresponding plaque area (r=0.56). Significant conventional CA lesions of the LM were present in just three patients (5%). Increased LM diameters are associated with the presence of atherosclerosis. MDCT CA indicates relevant features of LM atherosclerotic burden, as rupture and subsequent thrombosis of vulnerable plaques may develop from lesions characterised as nonsignificant at conventional CA.

Acute Results of Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation Using a Single Mesh Catheter

Catheter-based pulmonary vein isolation (PVI) is an established therapy to treat patients with paroxysmal atrial fibrillation. We evaluated the efficacy of a simplified interventional procedure for PVI by using a single mesh catheter for mapping as well as ablation and with guidance of fluoroscopic imaging only. Forty-eight patients with paroxysmal atrial fibrillation were screened by cardiac computed tomography for their anatomical suitability to undergo PVI with the high-density mesh ablator catheter as the only left atrial device. The procedure was performed in 26 patients (12 males, mean age 61 years) who met the criteria of four clearly separated pulmonary veins (PVs) with an ostial diameter of 15-25 mm. No three-dimensional mapping systems or additional ablation devices were used. In all 26 patients, all four PVs could be accessed and mapped with the high-density mesh ablator catheter. Electrical isolation was achieved in 99 of 102 (97%) of the pulmonary veins that revealed PV potentials. Mean total procedure time and fluoroscopy time were 187 +/- 36 minutes and 34.6 +/- 10.0 minutes, respectively. The single-catheter approach using the high-density mesh ablator catheter for mapping as well as ablation reveals a high acute success rate of PVI while, at the same time, reducing the complexity of the procedure, and the procedure time. Long-term data on clinical success are needed to justify this simplified approach.

Normal renal arterial anatomy assessed by multidetector CT angiography: Are there differences between men and women?

The purpose of this study was to determine renal arterial anatomy and gender differences in adults without renovascular disease using multidetector computed tomography angiography (MDCTA). MDCTA datasets of 399 patients were retrospectively reviewed. Measurements of the aortorenal diameters, the angulation of the renal ostia and pedicles as well as the distance between the origins of the renal arteries were measured. Differences in measurements between genders were tested for statistical significance using analysis of variance (ANOVA) and Pearson's Chi-Square tests. A total of 798 renal arteries were available for analysis in 207 female (mean age = 52.91 years) and 192 male patients (mean age = 53.04 years). Female patients were found to have smaller aortae (at the level of the right renal ostium) and bilateral renal arteries than males (mean aortic diameter M/F = 18.33/15.89 mm, mean right renal artery ostial diameter M/F = 5.06/4.59 mm, mean left ostial renal diameter M/F = 5.14/4.66 mm) (p < .001). There was no statistical significance for the renal ostia level in relation to the vertebrae and the majority of renal arteries originated at the L1 and L2 levels. The longitudinal distance between right and left renal artery ostia ranged from 0 to 32 mm (mean = 4,6 mm, median = 5mm). The mean anteroposterior orientation of the right renal ostia was M/F = 29.45 degrees/28.20 degrees , and M/F = -7.96 degrees/-11.14 degrees for left renal artery ostia. The mean anteroposterior orientation of the right renal pedicle was M/F = 41.37 degrees/44.34 degrees and M/F = 42.31 degrees/43.95 degrees for the left pedicle. There are some differences in normal renal arterial anatomy between genders. Normal renal arterial information is useful not only for planning and performing of endovascular and laparoscopic urologic procedures, but also for medical device development.

A new approach for contrast-enhanced X-ray imaging of the left atrium and pulmonary veins for atrial fibrillation ablation: rotational angiography during adenosine-induced asystole

Atrial fibrillation ablation is a complex procedure that requires detailed anatomic information about left atrium (LA) and pulmonary veins (PVs). The goal of this study was to test rotational angiography of the LA during adenosine-induced asystole as an imaging tool in patients undergoing atrial fibrillation ablation. Seventy patients with paroxysmal or persistent atrial fibrillation undergoing PV isolation were included. After transseptal puncture, adenosine (30 mg) was given intravenously, and during atrioventricular block, contrast medium was directly injected in the LA; a rotational angiography was performed (right anterior oblique 55 degrees to left anterior oblique 55 degrees). Rotational angiography images were assessed qualitatively in all patients and quantitatively in 45 patients in comparison with computed tomography (CT) images. The majority of rotational angiography imaging data (94%) were deemed at least 'useful' in delineating the LA-PV anatomy. The so-called 'ridge' between left superior PV and left atrial appendage was delineated in 90% of the patients. All accessory PVs were independently identified by rotational angiography and CT. A blinded quantitative comparison of PV ostial diameters showed an excellent correlation between rotational angiography and CT measurements (r > 0.90 for all PVs). No serious adverse effects occurred in association with adenosine. Intra-procedural contrast-enhanced rotational angiography of the LA-PV during adenosine-induced asystole is feasible and provides anatomical information of high diagnostic value for atrial fibrillation ablation.

Pre‐ and Postoperative Sinus Penetration of Nasal Irrigation

Endoscopic sinus surgery is an accepted treatment for medically recalcitrant chronic rhinosinusitis. Effective saline douching may improve long-term outcomes of chronic rhinosinusitis but is often impaired by postoperative ostial stenosis. The aim of this study is to determine a critical ostial size at which douching solution reliably enters the sinus cavities. Prospective study of consecutive patient cohort. Seventeen preoperative or well-healed postoperative endoscopic sinus surgery patients were irrigated with 5 mL blue food coloring mixed with 200 mL buffered saline from a squeeze bottle. The degree of sinus penetration, sinus ostial patency, and ostial size were endoscopically determined. Sinuses penetrated by blue dye had a significantly larger minimal ostial dimension (7.31 mm; 95% confidence interval 5.54-9.08) than those that had no blue dye penetration (1.26 mm; 95% confidence interval 0.86-1.66) as determined by Student t test. Chi-square analysis showed that operated sinuses were more likely to be penetrated than nonoperated sinuses (P = .0016) and obstructed sinuses (P = .0325). Logistic regression showed a 95% probability of penetration when the minimum ostial dimension is 3.95 mm or greater. Unoperated sinuses or cases with gross sinus ostial obstruction will not be reliably penetrated by sinus irrigant. A 3.95-mm ostial diameter seems to be the minimum size to guarantee penetration in paranasal sinuses to maximize the potential for topical sinus treatment.

Segmentation and registration of three-dimensional rotational angiogram on live fluoroscopy to guide atrial fibrillation ablation: A new online imaging tool

Three-dimensional rotational atriography (3DATG) was developed to supplement two-dimensional fluoroscopy with 3D volume reconstruction of the left atrium (LA), pulmonary veins (PV), and other structures. Until recently, 3DATG images could only be viewed separately and were not suitable to directly guide atrial fibrillation (AF) ablation. The purpose of this study was to evaluate the feasibility and accuracy of intraprocedural 3DATG. Three-dimensional rotational atriography with right atrial contrast injection was obtained using a Philips Allura Xper FD10 system in 30 patients with symptomatic AF who also underwent preprocedural computed tomographic (CT) scan. The majority (93%) of 3DATG image reconstructions were useful for guidance of catheter ablation. Nearly all PVs (94%), LA appendage (89%), and esophagus (100%) were successfully segmented. Measured PV ostial diameters compared using 3DATG and CT showed close concordance. Registration and re-registration of 3DATG overlay image was easily achieved with thoracic landmarks and validated by catheter placement demonstrating minimal discrepancy. Endoscopic views allowed for improved visualization of ostial position, dimensions, and navigation within the antrum. Lesion tagging on 3DATG overlay enhanced ablation guidance. Radiation exposure with 3DATG was significantly reduced compared with preprocedural CT scan (2.1 +/- 0.3 mSv vs 13.8 +/- 2.4 mSv, P <.001). Intraprocedural 3DATG imaging during AF ablation with online segmentation and superimposition on live fluoroscopy is feasible. Overlay provides valuable and accurate information on 3D surface outline and endoscopic PV location. Three-dimensional rotational atriography overlay is a new imaging method with reduced radiation exposure that may replace preprocedural CT scan for catheter navigation and ablation of AF.

R457 – Paranasal Aerosol Delivery of Budesonide Using PARI VibrENT

Problem Nasal sprays containing inhaled corticosteroids are widely used for the treatment of chronic, allergic and acute sinusitis. However, nasal sprays deposit mainly on the nasal valve and on the anterior portion of the nose, and are rapidly cleared from there. Clinical efficacy data are equivocal which might be caused by the inability of nasal sprays to reach into the posterior regions of the nose. Hence, a drug delivery system such as the PARI VibrENT designed to target the deep nose and the paranasal cavities via a pulsating aerosol may offer substantial benefits. Methods Nebulization efficiency was investigated by a novel cast deposition model of the upper airway including paranasal sinuses developed by PARI GmbH (Munich, Germany). 0.5 mL of a captisol enabled budesonide inhalation solution (CBIS, 480 μg Budesonide/ml) was completely aerosolized into each nostril. Consequently, in total 1 ml or 480 μg of Budesonide were administered in about 3 minutes. Sinus deposition was measured by extracting the deposited drug with a defined volume of solvent and assayed by HPLC. Results The mean values are as follows: the mean paranasal deposition was 15.9% of the initially charged budesonide amount. Only about 2% of the initial budesonide charge remained in the nebulizer, whereas 57.7% deposited in the nasal cavity, 15.2 % were expelled and 90.8 % of the drug was recovered. Deposition in the single sinus cavities ranged from 0.1% up to 7% depending significantly on sinus volume (p&lt;0.01) and ostium diameter (p&lt;0.01). Conclusion Relevant drug amounts could be delivered by the VibrENT into the nose and paranasal cavities of the nasal cast. Sinus deposition depends on its anatomy and was highest with ostium diameters from 1.5 to 3 mm. Significance Significant sinus deposition of abudesonide solution may be attainable through the use of the VibrENT nebulizer system. Clinical studies are warranted.

R458 – Drug Delivery to the Sinuses- Basics and Aerosol Dynamics

Problem Drug delivery to the sinuses via aerosols appears to be a very difficult task, since the paranasal cavities are virtually non-vented cavities. However, there is a scientifically traceable approach to transport aerosol to the sinuses via pressure differences using so-called “vibrating” or “sonic” aerosols which suggests that pressure fluctuations increase aerosol diffusion and ventilate dead spaces by flow induction. Methods The influence of droplet size, vibration frequency and flow rate on drug delivery to the nasal and paranasal cavities was studied in a human nasal cast model (NC). One ml of a Levofloxacin solution (100 mg/ml) was aerosolized into the NC by a VibrENT prototype nebulizer generating a slow, high density aerosol (MMD = 3.7μm) via a perforated vibrating membrane in connection with an adjustable pulsation source. Results Total paranasal cavity deposition was highest (-20 % of label claim) configured with ostia of 1 and 3 mm in diameter and sinus volumes of 7, 12 and 23 ml when VibrENT was operated at flow rates below 3 1/min and a pulsation frequency of 36 Hz. Delivery efficiency decreased at higher frequencies, higher flow rates and with larger aerosol droplets. Omission of pulsation resulted in no paranasal deposition and a drop in nasal cavity deposition from more than 50% to about 6%. Drug deposition to the sinuses is also significantly (p&lt;0.01) affected by the ostium diameter and sinus volume, being lowest (∼0.2 %) at a large ostium diameter (6 mm) and a low sinus volume (7 ml). Conclusion It is possible to deliver aerosol to the sinuses but physical boundary conditions like pulsation frequency, aerosol size and flow rate have to be considered for an efficient transport as well as sinus anatomy. PARI VibrENT addresses these requirements. Significance Efficient drug transport to the sinuses enables novel therapeutic approaches.

Imaging anatomy of the infraorbital ethmoid cells on multislice CT

Objective To study the anatomic characteristics of the infraorbital ethmoid cells on muhislice CT(MSCT)and explore the relationship between the infraobital ethmoid cells and mueosal swelling of sinuses.Methods Two hundred sixty patients(520 sides) of consecutive axial scans by GE HisDeed VCT and the multiplunar reformation(MPR),virtual endoscopy(VE)reconstruction images by GE AW 4.2 workstation were reviewed retrospectively.The following CT features were assessed:(1)the anatomic characteristics of the infraobital ethmoid ceils,including the frequency of identification,origin,classification.(2)presence of mucosal swelling of sinuses,(3)the maximal transversal diameter of the inflraobital ethmoid cells in ostium of maxillary sinus(perpendicular to the uncinate process),and the diameter of the ostium of maxillary sinus,(4)presence of infraobital ethmoid ceils inflammatory findings and a contact between the mucosal surface of the ostium of maxillary sinus.The results were analyzed by using Chi-square test and logistic regression analysis with the statistical software SPSS 11.5.Results (1) UniLateral infraobital ethmoid cells were f10und in 68 patients(26.1%),and bilateral infraobital ethmoid cells were found in 81 patients(31.2%).Infraobital ethmoid ceHs were found in 230 sides on left Bide (120 sides)and right side(110 sides).(2)Infraobital ethmoid cells originated from the anterior ethmoid cells in 124 sides(53.9%)and from posterior ethmoidal cells in 62 sides(27%),originated from both the anterior ethmoidal cells and the posterior ethmoidal cells in 44 sides(19.1%).(3)The classification of the infraobital ethmoid cells included three types.Infraobital ethmoid cells with different origination differed significantly in theirtypes(x2=193.433,P 0.05).The maximal transversal diameter of the infraobital ethmoid cells in ostium of maxillary sinus did not differ significantly between the cases with or without mucosal swelling of sinuses(t=0.273,P>0.05).and the diameter of the ostium of maxillary sinus were not significantly related with mucosal swelling of sinuse8 (Wald=2.534,P>0.05).Presence of infraobital ethmoid cells inflammatory findings (Wald=10.817. P<0.01,OR=4.125)and a contact between the mucosal surface of the ostium of maxillary sinus (Wald= 6.640,P<0.01,OR=3.728)were significantly related to mucosal swelling of 8inuses. Conclusions (1)MSCT scan could clearly demonstrate the detailed information of infraobital ethmoid ceIIs.(2)The presence of infraobtial ethmoid cells Was not a risk factor for chronics sinusitis. When we assess inflraobtial ethmoid cells as a possible etiologic factor in chronics sinusitis we should observe presence of infraobital ethmoid cells inflammatory findings and a contact between the mucosal surface of the ostium of maxillary sinud. Key words: Ethmoid Sinus; Anatomy; Tomography.X-ray computed

Measurements of pulmonary vein ostial diameter and distance to first bifurcation: A comparison of different measurement methods

The purpose of this study was to evaluate the agreement between axial, multiplanar reformatted (MPR) and semi-automated software measurements of pulmonary vein ostial diameters and distance to the first bifurcation. CT examinations of the thorax were retrospectively reviewed in 150 consecutive patients. The pulmonary vein ostial diameter and distance to the first bifurcation of the four main pulmonary veins were independently measured. The three measurement methods were compared using a Bland–Altman test. There was no significant variation between pulmonary vein ostial diameter measurements for the superior pulmonary veins across the three measurement methods. There was significant variation between the semi-automated program and both the axial ( p = 0.001) and MPR ( p < 0.001) measured diameters for the right inferior pulmonary vein ostial diameter and between the MPR and semi-automated program measurements ( p = 0.02) for the left inferior pulmonary vein ostial diameter. There was no significant variation between the pulmonary vein distance to first bifurcation measurements for any pulmonary vein across the three measurement methods. However, from a clinical perspective, differences were negligible; therefore, the clinician may confidently use any of the three measurement methods presented.

Noninvasive coronary venous system imaging using 64-slice CT angiography

Objective To evaluate the 64-slice CT angiography in characterizing the coronary venous anatomy and the arterio-venous relationship.Methods Sixty-four slice CT coronary veins angiography images of 300 patients(187 men and 113 women,)were analyzed.The visibility of the coronary veins and arterio-venous spatial relationship were assessed qualitatively on two-and three-dimensional displays.The diameter of the coronary sinus ostium(CSO),middle cardiac vein ostium(MCVO)and posterior vein of left ventricle ostium(PVLVO)were measured.All data was statistically processed with SPSS for Windows.Results The CS,great cardiac vein(GCV)and MCV could be clearly visualized in all of the images.1-3 branches of PVLV could be observed in 273 patients(91.0%).Small cardiac vein(SCV)and Marshall vein were found in 56(18.7%)and 24(8.0%)cases respectively.Three patients had permanent vena cava superior on the left and one patient had a CS diverticulum.Posterior descending artery(PDA)was concomitant with MCV in 189 cases(63.0%)and intersected with MCV in 96 cases(32.0%).Left circumflex artery(LCX)was concomitant with CS in 122 cases(40.7%),intersected with MCV in 15 cases(5.0%),and intersected with PVLV in 104 cases(34.7%).There were no significant differences in age,sex and CHD groups among CSO,MCV,PVLV value.The supero-inferior diameter of CSO had a significant difference between male and female(F=6.67,P＜0.05).Conclusion Sixty-four slice CT venous angiography is able to be used for guiding electrophysiological procedures,which is especially useful due to the considerable variations in venous anatomy. Key words: Coronary vessels; Tomography,X-ray computed; Anatomy

Assessment of coronary sinus anatomy between normal and insufficient mitral valves by multi-slice computertomography for mitral annuloplasty device implantation☆

Latest techniques enable positioning of devices into the coronary sinus (CS) for mitral valve (MV) annuloplasty. We evaluate the feasibility of non-invasive assessment to determine CS anatomy and its relation to MV annulus and coronary arteries by multi-slice CT (MSCT) in normal and insufficient MV. Fifty patients (33 males, 17 females, age 67+/-11 years) were studied retrospectively by 64-MSCT scans for anatomical criteria regarding CS and its relation to MV annulus and circumflex artery (CX). We included 24 patients with severe mitral insufficiency and 26 with no MV disease. Diameter of MV, of proximal and distal ostium of CS, length and volume of CS, angle between anterior interventricular vein (AIV) and CS, caliber change of CX before, under/over and after CS were analysed. Different anatomical correlations were demonstrated: distance of MV annulus to CS, CX to CS. Diameter of proximal CS ostium was significantly larger in insufficient MV compared to normal MV (11+/-2.8 mm vs 9.9+/-2.5 mm; p<0.024). CS was significantly longer in patients with insufficient MV (125.4+/-17 mm vs 108.9+/-18 mm; p<0.003) with also significant differences in volume of CS (p<0.039). Significant difference in annulus diameter, 46.1+/-6mm (insufficient MV) versus 39.5+/-7.5 mm, p<0.004 was observed. Angle CS-AIV was 103.5+/-29 degrees (range 52 degrees -144 degrees ) in insufficient valves versus 118.2+/-24.5 degrees (range 73 degrees -166 degrees ) in normal valves with a tendency to higher angles in normal valves (p=0.06). Distance of MV annulus to CS measured 16+/-4.1/14.2+/-3.6 mm (insufficient/normal MV) without significant difference between groups. In 15 patients CX ran under CS. Eighty-four percent of these patients (13/15) show a decrease in CS caliber in the area of intersection. In 14 patients CS ran over and in one patient the diameter of the CS at intersecting region was smaller. In 16 patients no direct point of contact was visible, in five patients CX to CS positioning was not evaluable. There is a significant anatomic difference between normal and insufficient MV, which might be the basis for any interventional approaches through the CS. Exact measurements of all structures and its anatomic correlations are possible with MSCT, which allows pre-interventional planning.

Renal Vein Ostium Wall Invasion of Renal Cell Carcinoma With an Inferior Vena Cava Tumor Thrombus: Prediction by Renal and Vena Caval Vein Diameters and Prognostic Significance

We determined whether renal vein ostium wall invasion could be predicted by renal vein and inferior vena cava diameter on imaging. We also determined whether it is a prognostic factor for recurrence and survival after radical nephrectomy and thrombus ablation for renal cell carcinoma with an inferior vena cava tumor thrombus. From January 2000 to January 2006 nephrectomy for renal cell carcinoma was performed in 446 patients, of whom 32 (7.2%) underwent inferior vena cava thrombus extraction with complete resection of the renal vein ostium. When necessary, inferior vena cava partial and circumferential ablation was done in 5 and 8 patients, respectively, as well as replacement for thrombus adhesions. The largest coronal or axial diameter of the renal vein ostium and inferior vena cava anteroposterior diameter were measured on preoperative magnetic resonance imaging. Renal vein ostium wall invasion was assessed in all patients and determined microscopically by tumor cell infiltration into the intima. ROC curves were used to assess the value of these measurements for diagnosing patients with renal vein ostium invasion with 90% sensitivity. The risk of recurrence and survival was analyzed. Renal vein ostium wall invasion was present in 13 of 32 patients (40.6%). It significantly correlated with mean +/- SD inferior vena cava anteroposterior diameter (27.8 +/- 10.2 vs 17.3 +/- 6.8 mm, p = 0.01) and with the largest mean renal vein ostium diameter (22.3 +/- 7.9 vs 12.6 +/- 6.9 mm, p = 0.01). The upper level of the inferior vena cava thrombus correlated with renal vein ostium invasion (p = 0.002). The inferior vena cava anteroposterior diameter or renal vein ostium diameter cutoff value to predict wall invasion with 90% sensitivity was 18 and 14 mm, respectively. The AUC was 0.78 for inferior vena cava diameter and 0.86 for renal vein ostium diameter. No inferior vena cava recurrence was observed. Renal vein ostium wall invasion was associated with a higher risk of recurrence and decreased specific survival (p = 0.01 and 0.03, respectively). The association of ostium renal vein wall invasion with death from renal cell carcinoma was seen on multivariate analysis after adjusting for tumor size, TNM stage and thrombus level (RR 5.9, 95% CI 1.45-30.8, p = 0.01). Preoperative imaging measurements of renal vein and inferior vena cava diameter can accurately predict renal vein ostium wall invasion. Renal vein ostium wall invasion is an independent prognostic marker that is associated with a higher risk of recurrence and decreased specific survival.

Intraprocedural Volume Imaging of the Left Atrium and Pulmonary Veins with Rotational X‐Ray Angiography: Implications for Catheter Ablation of Atrial Fibrillation

The use of preprocedural CT or MR imaging to generate patient-specific cardiac anatomy greatly facilitates catheter ablation of the left atrium and pulmonary veins (LA-PVs) to treat atrial fibrillation (AF). This report details the accuracy and utility of an intraprocedural means to generate 3-D volumetric renderings of the LA-PV anatomy: contrast-enhanced rotational X-ray angiography (3DRA). Preprocedural CT or MR imaging and intraprocedural rotational angiography was performed in 42 patients undergoing AF ablation procedures. Initially, pulmonary artery (PA) bolus-chase contrast injections were performed (20 mL, 20 mL/s) to establish pulmonary transit time and cardiac isocentering. Depending on cardiac size, either a single PA injection (80-100 mL, 20 mL/s) or two separate dedicated left/right PA branch injections were performed (60 mL each, 20 mL/s). For the latter, the two volumes of the left/right portions of the LA-PVs were registered and fused. LA-PV 3DRA images were assessed qualitatively and quantitatively in comparison with CT/MR images. The majority of the 3DRA acquisitions (71%) were deemed at least "useful" in delineating the LA-PV anatomy. The LA appendage was delineated in 57% of the cases. A blinded quantitative comparison of PV ostial diameters resulted in an absolute difference of only 2.7 +/- 2.3 mm, 2.2 +/- 1.8 mm, 2.4 +/- 2.2 mm, and 2.2 +/- 2.3 mm for the left-superior, left-inferior, right-superior, and right-inferior PVs, respectively. The feasibility for registering the 3DRA image with real-time electroanatomical mapping was also demonstrated. Intraprocedural contrast-enhanced rotational angiography provides volumetric 3-D images of the LA-PVs of comparable diagnostic value to dedicated preprocedural CT/MR imaging.

Reliability of MDCT measurements of pulmonary vein ostial diameter and distance to first bifurcation: an interobserver study comparing radiologists with a semiautomated software

The purpose of this study was to evaluate agreement between radiologists and semiautomated software measurements of pulmonary vein ostial diameters and distance to the first bifurcation. Computed tomography (CT) examinations of the thorax were retrospectively reviewed in 50 consecutive patients. The pulmonary vein ostial diameter and distance to the first bifurcation of the four major, and the middle lobe pulmonary veins, were measured independently by two experienced cardiothoracic radiologists, and using CardEP semiautomated software. The two measurement methods were compared. Analyses were performed using a Bland-Altman test. There is no significant variation between readers or between readers and the software in pulmonary vein ostial diameter measurements for the four major pulmonary veins. There is significant variation between the first reader (P = 0.03) and between the second reader and the software (P = 0.01) in vein diameter measurements for the middle lobe vein. And, also between the second reader and the first reader for the right inferior (P = 0.02) and left inferior (P = 0.02) pulmonary vein distance to first bifurcation, and between the second reader and the software for the right inferior (P = 0.01) and left inferior vein (P = 0.02) distance to first bifurcation. There is good interobserver agreement when measuring the major pulmonary vein diameters. Measurements of distances to first bifurcation were less reliable across readers and the readers and the semiautomated software.

The ambiguous pulmonary venoatrial junction: a new perspective

The pulmonary venoatrial junction (PVAJ) has recently received attention due to the widespread use of catheter ablation for atrial fibrillation. However, the literature lacks a consensus in the definition of the PVAJ. We aim to review the inconsistent definitions for the PVAJ and related implications in imaging and catheter ablation for atrial fibrillation. The PVAJ as described by embryology, gross anatomy, histology and imaging is ambiguous, leading to disparities in its definition. Because of differing definitions of the PVAJ, there is a broad range in the prevalence of anatomic variations, including (1) percentage of common pulmonary veins (10-79% on the left), (2) supernumerary pulmonary veins (10-42%) and (3) ostial diameter and shape. We postulate several reasons for this broad range in the described prevalence of anatomic variation of the PV as follows: (1) different definitions of the PVAJ, (2) different vantage points, (3) different imaging modalities, and (4) different prevalence of anatomic variants among different study populations. The ambiguous PVAJ with its gradual transition from the left atrium to the pulmonary veins defies precise definition even though it plays an important role in the management of atrial fibrillation. Physicians should be aware of variability in the language used to describe the PVAJ and resultant discrepancy in reported anatomical information.