Evaluation of the coronary venous system using electron beam computed tomography

A Rare Variant of the Great Cardiac Vein Draining Directly into the Superior Vena Cava

OBJECTIVE

A routine dissection of the cadaver of a 67-year-old man revealed a very rare morphological variant of the great cardiac vein (GCV).

PRESENTATION

The vein originated in the upper third of the anterior interventricular sulcus, crossed the anterior interventricular artery superficially, ran beneath the circumflex artery, crossed the transverse pericardial sinus, and drained directly into the superior vena cava.

CONCLUSION

This variant of the GCV is interesting due to its rarity. It is important to know about it for procedures that require venous access such as coronary surgery requiring retrograde cardioplegia, surgical ablation of aberrant conducting pathways, pacemaker insertion, and valve surgery.

Optimization of free-breathing whole-heart 3-dimensional cardiac magnetic resonance imaging at 3 tesla to identify coronary vein anatomy and to compare with multidetector computed tomography

OBJECTIVE

This study optimizes use of 3-T magnetic resonance imaging (MRI) to delineate coronary venous anatomy and compares 3-T MRI with multidetector computed tomography (MDCT) measurements.

METHODS

The study population included 37 consecutive subjects (22 men, 19-71 years old). Whole-heart contrast-enhanced MRI images at 3 T were acquired using segmented k-space gradient echo with inversion recovery prepared technique. The MDCT images were obtained using nonionic iodinated contrast.

RESULTS

The coronary sinus and great cardiac, posterior interventricular, and anterior interventricular veins were visualized in 100% of cases by both MRI and MDCT. Detection of the posterior vein of the left ventricle and the left marginal vein by MRI was 97% and 81%, respectively. Bland-Altman plots showed agreement in ostial diameter measured by both modalities with correlation coefficients ranging from 0.5 to 0.76. Vein length and distances also agreed closely.

CONCLUSIONS

Free-breathing whole-heart 3-dimensional MRI at 3 T provides high-spatial-resolution images and could offer an alternative imaging technique instead of MDCT scans.

Normal anatomy and variants of the venous cardiac system in MDCT coronary angiography

Three separate venous systems drain the blood returning from the heart walls. These veins are characterised by remarkable variability in terms of frequency, size and course. The knowledge of cardiac venous anatomy is of primary importance during interventional cardiac procedures that require catheterisation of cardiac veins. Some anatomical variants may hinder or contraindicate access to target veins. Coronary angiography (CA) with multidetector computed tomography (MDCT-CA) and multiplanar reformations (MPR), maximum intensity projection (MIP) and 3D reconstructions provides noninvasive visualisation of normal cardiac veins and anatomical variants. The purpose of this pictorial review is to describe by MDCT-CA the anatomy and main variants of the cardiac venous system.

Anatomical reconstructions of the human cardiac venous system using contrast-computed tomography of perfusion-fixed specimens

A detailed understanding of the complexity and relative variability within the human cardiac venous system is crucial for the development of cardiac devices that require access to these vessels. For example, cardiac venous anatomy is known to be one of the key limitations for the proper delivery of cardiac resynchronization therapy (CRT)(1) Therefore, the development of a database of anatomical parameters for human cardiac venous systems can aid in the design of CRT delivery devices to overcome such a limitation. In this research project, the anatomical parameters were obtained from 3D reconstructions of the venous system using contrast-computed tomography (CT) imaging and modeling software (Materialise, Leuven, Belgium). The following parameters were assessed for each vein: arc length, tortuousity, branching angle, distance to the coronary sinus ostium, and vessel diameter. CRT is a potential treatment for patients with electromechanical dyssynchrony. Approximately 10-20% of heart failure patients may benefit from CRT(2). Electromechanical dyssynchrony implies that parts of the myocardium activate and contract earlier or later than the normal conduction pathway of the heart. In CRT, dyssynchronous areas of the myocardium are treated with electrical stimulation. CRT pacing typically involves pacing leads that stimulate the right atrium (RA), right ventricle (RV), and left ventricle (LV) to produce more resynchronized rhythms. The LV lead is typically implanted within a cardiac vein, with the aim to overlay it within the site of latest myocardial activation. We believe that the models obtained and the analyses thereof will promote the anatomical education for patients, students, clinicians, and medical device designers. The methodologies employed here can also be utilized to study other anatomical features of our human heart specimens, such as the coronary arteries. To further encourage the educational value of this research, we have shared the venous models on our free access website: www.vhlab.umn.edu/atlas.

Familial occurrence of atrioventricular nodal reentrant tachycardia in a mother and her son

Atrioventricular nodal reentrant tachycardia (AVNRT), caused by a reentry circuit involving fast and slow atrioventricular nodal pathways, is one of the most common types of paroxysmal supraventricular tachycardias. While familial Wolff-Parkinson-White syndrome has been well recognized, familial AVNRT has been rarely reported. We report a familial occurrence of AVNRT in a mother and her son, who were symptomatic and successfully treated with radiofrequency catheter ablation of slow pathway.

Cardiac resynchronization therapy: double cannulation approach to coronary venous lead placement via a prominent thebesian valve

We report identification of a prominent Thebesian valve by cardiovascular computed tomography (CT) angiography impeding cannulation of the coronary sinus, with subsequent successful coronary venous lead placement with cannulation of the coronary sinus ostium via a transvenous femoral vein approach and subsequent cannulation of the ostium with the coronary venous lead with a left subclavian approach. A 57-year-old man with nonischemic dilated cardiomyopathy, New York Heart Association Class III heart failure, left bundle branch block, and an ejection fraction of 15%, underwent an attempted cardiac resynchronization therapy implantable cardiac defibrillator (ICD). As the coronary sinus ostium could not be cannulated, a dual chamber ICD was placed. The patient subsequently underwent cardiovascular CT angiography, which identified a prominent Thebesian valve at the coronary sinus ostium as the anatomic obstacle to cannulation. Reattempted transvenous cardiac resynchronization therapy was accomplished successfully with a double cannulation approach: cannulation of the coronary sinus ostium with a catheter via a transvenous femoral vein approach and subsequent cannulation with the coronary venous lead via a left subclavian approach. When a prominent Thebesian valve is identified as an obstacle to transvenous left ventricular lead placement, cannulation of the coronary sinus by an alternate venous approach may allow for a coronary venous route rather than necessitate an epicardial approach.

Cardiac imaging: Part 2, normal, variant, and anomalous configurations of the coronary vasculature

OBJECTIVE

Noninvasive imaging of the heart and coronary vasculature using CT and MRI is a new and exciting opportunity for radiologists. The purpose of this pictorial essay is to review normal and variant anatomy of the coronary arteries and of several coronary anomalies that may be clinically significant. The coronary veins and artifacts simulating disease will also be briefly covered. This article will help radiologists learn and review normal coronary anatomy, normal variants, and coronary anomalies and recognize pitfalls, such as coronary veins and artifacts, that may be confusing when first encountered.

CONCLUSION

The coronary arteries generally are predictable in their origin, course, and perfusion territories. Standardized reporting systems exist for describing the location of specific lesions, and radiologists who interpret CT and MR coronary images should be aware of and should attempt to integrate these reporting schemes into clinical practice.

Time-resolved analysis of coronary vein motion and cross-sectional area

PURPOSE

To quantify periods of low motion and cross-sectional area changes of the coronary veins during the cardiac cycle for planning magnetic resonance coronary venograms (MRCV).

MATERIALS AND METHODS

Images were acquired from 19 patients with coronary artery disease (CAD) and 13 patients scheduled for cardiac resynchronization therapy (CRT). The displacement and cross-sectional area of the coronary sinus was tracked, and periods of low motion were defined as consecutive time points during which the position of the coronary sinus remained within a 0.67-mm diameter region. Patients were classified as systolic dominant or diastolic dominant based on the relative duration of their low motion periods.

RESULTS

All CRT patients were classified as systolic dominant, and 32% of these had no separate diastolic rest period. All CAD patients with ejection fraction < 35% were classified as systolic dominant, while all CAD patients with ejection fraction > 35%were diastolic dominant. In 77% of all subjects, the cross-sectional area of the coronary sinus was larger in systole than in diastole.

CONCLUSION

The movement of the coronary sinus can be used to classify patients as either having a longer systolic or diastolic rest period. The classification of the CRT patients as systolic dominant suggests that MRCVs be acquired in systole for CRT planning; however, each patient's low motion periods should be categorized to ensure the correct period is being used to minimize motion artifacts.

Non-invasive evaluation of the coronary venous system in patients with chronic systolic heart failure by 64-detector computed tomography

BACKGROUND

Imaging coronary venous systems to guide transcatheter cardiac interventions are becoming increasingly important, particularly in heart failure patients who are selected for cardiac resynchronization therapy (CRT). Failure of left ventricular (LV) lead placement during the procedure has been attributed to the inability to insert catheters into the coronary sinus and the lack of suitable side branches.

PURPOSE

To comparatively assess the value of a 64-detector MDCT examination in visualizing the cardiac veins and evaluating the morphological characteristics of the coronary venous system in patients with and without chronic systolic heart failure (SHF).

MATERIAL AND METHODS

A 64-detector MDCT examination of the heart was performed in 26 consecutive patients (five women, 21 men; mean age 57.80 ± 12.05 years; range 27-81 years) with chronic SHF. The morphological characteristics of the coronary venous system, such as the diameter, the distances between the venous tributaries, the angle and the tortuosity, were evaluated. The group was compared with a subgroup of 52 subjects without SHF (LV ejection fraction >40%) matched for age, sex, and the risk factors for coronary artery disease.

RESULTS

The coronary sinus (CS), great cardiac vein (GCV), anterior interventricular vein (AIV), and posterior interventricular vein (PIV) were visualized in all 78 individuals. The posterior vein of the left ventricle (PVLV) (63/78), left marginal vein (LMV) (72/78), and the small cardiac vein (SCV) (50/78) were visualized in SHF and control patients (p = NS). The lengths between venous tributaries were higher (p > 0.05) and more dilated (P < 0.001 for CS, GCV, AIV, PVLV, LMV; p = 0.001 for PIV) in the cases with SHF compared with the control population. The angle between the CS-GCV axis and the venous branches was wider (p = 0.02 for LMV and PIV, p = 0.001 for PVLV) and did not have any correlation with the LV diameter in cases with SHF. There was no difference between the SHF and control groups in terms of the tortuosity of PVLV and LMV (p = NS).

CONCLUSION

The study demonstrated an increase in the diameters, lengths, and angulations with the CS-GCV axis of the coronary veins in cases with SHF. A 64-detector MDCT is a feasible tool for non-invasive evaluation of the coronary venous system and may provide considerable information regarding numbers and morphology of coronary veins before percutaneous transcatheter cardiac therapy.

Assessment of coronary veins in patients with isolated coronary artery ectasia by antegrade coronary venous angiography

BACKGROUND

Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of the coronary arteries. The most common cause of CAE is atherosclerosis but other possible etiologies include congenital abnormalities and inflammatory and connective tissue disease. Earlier studies have documented the association of CAE with the presence of aneurysms in other vascular beds. However, cardiac venous system in patients with isolated CAE has not been studied earlier. In this study, we aimed to assess coronary venous vessels by antegrade coronary venous angiography in patients with isolated CAE.

METHODS

Twenty-four patients with isolated CAE without significant stenosis and 21 age-matched and sex-matched controls without CAE were included in this study. The anatomy of the coronary venous system was imaged in a left anterior oblique view at an angle of 45° by antegrade coronary angiography.

RESULTS

Patients with isolated CAE had significantly larger coronary veins compared with control individuals with angiographically normal coronary arteries (coronary sinus ostium: 10.1 ± 1.0 vs. 8.5 ± 2.2 mm, respectively, P=0.003; coronary sinus mid level: 7.9 ± 1.4 vs. 6.5 ± 1.6, respectively, P=0.003; great cardiac vein: 5.6 ± 1.0 vs. 4.3 ± 0.8, respectively, P=0.001; middle cardiac vein: 3.9 ± 1.3 vs. 3.7 ± 1.4, respectively, P=0.52; posterior or lateral vein: 3.2 ± 1.1 vs. 2.4 ± 0.7, respectively, P=0.016).

CONCLUSION

We have shown for the first time a significant dilatation in the coronary veins in patients with isolated CAE, suggesting the presence of a more extensive vascular destruction in the coronary circulation.

[Coronary CTA evaluation of the relationship between mitral valve annulus and coronary circulation: implications for percutaneous mitral annuloplasty]

PURPOSE

To evaluate anatomical relationships between mitral annulus (MA), coronary arteries and coronary sinus (CS) in two groups of patients with and without moderate mitral insufficiency on coronary CTA to identify candidates to percutaneous mitral valve annuloplasty via the coronary sinus without risk of coronary artery occlusion. MATERIALS AND METHODS. Fifty-one ECG-gated coronary CTA examinations, obtained during injection of iodinated contrast material on a 16 MDCT were retrospectively reviewed. The mitral valve annulus diameter, anatomical relationships between CS and coronary arteries and MA-CS distance were compared between both patient groups.

RESULTS

The group with mitral insufficiency included 16 patients and the control group included 35 patients. The AP diameter of the MA was 45,7+/-5,2 mm in the group with mitral insufficiency, significantly larger (p=0.0009) compared to the control group (39,3+/-5,9 mm). In 70.4% of cases, the CS was located next to a coronary artery in an overlapping configuration. The unfavorable anatomical configuration with regards to annuloplasty appeared related to mitral insufficiency (p=0.0539). The distance between MA and CS was greatly variable with the CS routinely extending over the left atrial surface: the distance was significantly (p=0.0002) greater for all patients along the posterior surface (8,1+/-3,8 mm) compared to the lateral surface (5,2+/-4,6 mm) with this différence persisting within both groups: p=0.004 for patients with mitral insufficiency and p=0.0001 for control patients.

CONCLUSION

Our results demonstrate the value of coronary CTA in selecting candidates to percutaneous mitral annuloplasty. In 70.4% of cases, the CS overlaps a coronary artery with risk of compression at the time of annuloplasty.

Magnetic resonance imaging and computed tomography in assessing cardiac veins and scar tissue

The success of cardiac resynchronization therapy is influenced by several issues including cardiac venous anatomy and myocardial scar tissue. This article discusses non-invasive imaging modalities that could contribute significantly to the selection process of cardiac resynchronization therapy (CRT) candidates: multi-slice computed tomography to depict the coronary sinus tributaries and magnetic resonance imaging to identify scar tissue.

Magnetic resonance cardiac vein imaging: relation to mitral valve annulus and left circumflex coronary artery

OBJECTIVES

To evaluate in vivo anatomical relationships between the coronary sinus-great cardiac vein (CS-GCV), the mitral valve annulus (MVA), and left circumflex coronary artery (LCX) with cardiovascular magnetic resonance.

BACKGROUND

The CS-GCV has become an anatomical structure of interest because it provides a way of access to the heart for a number of interventional procedures. Previous reports demonstrate that the postulated close anatomical proximity of the CS-GCV to the MVA does not always hold true in patients, both in autopsy specimens and in vivo by computed tomography.

METHODS

In 31 participants (24 volunteers and 7 patients; 15 men; 42 +/- 19 years), cardiovascular magnetic resonance was performed for noninvasive evaluation of the coronary sinus and of the coronary arteries using whole-heart imaging and intravascular contrast agents. Three-dimensional reconstructions, standard orthogonal planes, and unprocessed raw data were used to assess CS-GCV anatomy and its relation to the MVA and the LCX along their entire course.

RESULTS

The CS-GCV was located behind the left atrium in all examined participants, at a minimum distance of 8.6 +/- 3.9 mm from the MVA. In 80% of the participants, the LCX crossed the CS-GCV inferiorly, between the CS-GCV and the MVA. The CS-GCV and the LCX had a parallel course for 26.2 +/- 23.0 mm, with great variability of location and length. In several participants, the CS-GCV had a long parallel course, but in other participants, the LCX crossed below the CS-GCV at a discrete point.

CONCLUSIONS

In all participants, the CS-GCV coursed behind the left atrium rather than behind the MVA. In the majority of the participants, the LCX coursed between the CS-GCV and the MVA. These anatomical relationships should be kept in mind when referring a patient for interventional procedures requiring the access to the CS-GCV, and cardiovascular magnetic resonance might provide important information for the selection of candidates for these procedures.

Trans-Coronary-Venous Interventions

The coronary venous system is routinely targeted during electrophysiological measurements or cardiac resynchronization therapy. However, several novel interventional techniques require coronary venous catheterization and visualization as well as transvenous delivery of devices and/or therapeutic agents. Recent reports suggest the possibility of a transvenous approach for the interventional treatment of refractory angina and mitral valve regurgitation. In addition, the coronary venous system has been used as a route for the delivery of stem cells in patients with left ventricular dysfunction due to ischemic heart disease. We review the potential value of using a coronary venous approach in association with recent therapeutic developments in the interventional treatment of structural and ischemic heart disease. We will also discuss techniques related to coronary venous catheterization.

Visualization of the cardiac venous system using cardiac magnetic resonance

We sought to investigate the value of cardiac magnetic resonance to depict cardiac venous anatomy. For cardiac resynchronization therapy the lead for the left ventricle is usually placed by transvenous approach into a tributary of the coronary sinus (CS). Knowledge of the anatomy and variations of the cardiac venous system may facilitate the positioning of the left ventricle lead. The cardiac magnetic resonance examinations of 23 subjects (16 volunteers and 7 patients) were retrospectively analyzed. All examinations were performed using navigator-gated whole-heart steady-state free precession coronary artery imaging after administration of intravascular contrast agents (gadofosveset in volunteers; Gadomer-17 in patients). The cardiac venous system was visualized in all subjects. The most frequent anatomical variant observed (in 12 subjects [52%]) was a connection of the small cardiac vein to the CS at the crux cordis. In 10 subjects (44%) the small veins entered the right atrium independently from the CS, and the posterior interventricular vein was connected to the CS at the crux cordis. Only one subject had a disconnection between the CS and posterior interventricular vein, which entered into the right atrium independently. The mean distance of the posterior vein of the left ventricle and the left marginal vein to the ostium of the CS was 15.2+/-4.7 mm and 49.7+/-14.1 mm, respectively. In conclusion, the anatomy of the cardiac venous system and its anatomical variability can be described using cardiac magnetic resonance. Its preimplantation visualization may help to facilitate the implant procedure and to reduce fluoroscopy time.

Role of multislice computed tomography for preprocedural evaluation before revision of a chronically implanted transvenous left ventricular lead

The purpose of this study was to determine the feasibility of multislice computed tomography (MSCT) to assess the coronary sinus (CS) and its tributaries in patients who are undergoing cardiac resynchronization therapy and need a left ventricular (LV) lead revision. Preprocedural imaging modality, which may enable delineation of the cardiac venous anatomy in patients who need LV lead replacement, has not yet been evaluated. Ten patients with heart failure with previously implanted cardiac resynchronization therapy devices, who presented with worsening heart failure, were studied with MSCT and tissue Doppler imaging echocardiography before LV lead replacement. MSCT was performed to evaluate patency of the CS and coronary veins, and tissue Doppler imaging echocardiography assessed the region and the magnitude of mechanical dyssynchrony. An excellent concordance in the vein diameter, location, and status between MSCT and angiography was found. Apart from the need to perform a venoplasty in 1 patient and an unsuccessful lead explantation in another patient, all other anatomic issues were correctly predicted by MSCT. CS or vein occlusion were present in 4 patients, and in 3 of them surgical LV lead replacement was performed. Identification of a patent venous system enabling successful transvenous lead implantation was possible in 2 patients. Direct visualization of the proximity of the target vein to the phrenic nerve and the diaphragm guided lead selection and position in 4 patients. In conclusion, MSCT may be used to delineate the coronary venous anatomy in patients in whom LV lead replacement is needed to help strategize whether a transvenous or transthoracic approach may be preferred for LV lead revision.

Variability of coronary venous anatomy in patients undergoing cardiac resynchronization therapy: a high-speed rotational venography study

BACKGROUND

Imaging the coronary venous (CV) tree to delineate the coronary sinus and its tributaries can facilitate electrophysiological procedures, such as cardiac resynchronization therapy (CRT) and catheter ablation. Venography also allows visualization of the left atrial (LA) veins, which may be a potential conduit for ablative or pacing strategies given their proximity to foci that can trigger atrial fibrillation.

OBJECTIVE

The aim of this study was to provide a detailed description of CV anatomy using rotational venography in patients undergoing CRT.

METHODS

Coronary sinus (CS) size and the presence, size, and angulation of its tributaries were determined from the analysis of rotational CV angiograms from 51 patients (age 68 +/- 11 years; n = 12 women) undergoing CRT.

RESULTS

The CS, posterior veins, and lateral veins were identified in 100%, 76%, and 91% of patients. Lateral veins were less prevalent in patients with a history of lateral myocardial infarction than in patients without such a history (33% vs. 96%; P = .014). The diameters of the CS and its tributaries were fairly variable (7.3-18.9 mm for CS, 1.3-10.5 mm for CS tributaries). The CS was larger in men than in women and in cases of ischemic than in cases of nonischemic cardiomyopathy (all P <.05). The vein of Marshall, the most constant LA vein, was identified in 37 patients; its diameter is 1.7 +/- 0.5 mm, and its takeoff angle is 154 degrees +/- 15 degrees , making the vein potentially accessible for cannulation.

CONCLUSIONS

Differences in CV anatomy that are related to either gender or coronary artery disease could have important practical implications during the left ventricular lead implantation. The anatomical features of the vein of Marshall make it a feasible potential conduit for epicardial LA pacing.

Noninvasive Evaluation of Coronary Sinus Anatomy and Its Relation to the Mitral Valve Annulus

BACKGROUND

Percutaneous mitral annuloplasty has been proposed as an alternative to surgical annuloplasty. In this respect, evaluation of the coronary sinus (CS) and its relation with the mitral valve annulus (MVA) and the coronary arteries is relevant. The feasibility of evaluating these issues noninvasively with multislice computed tomography was determined.

METHODS AND RESULTS

In 105 patients (72 men, age 59+/-11 years), 64-slice multislice computed tomography was performed for noninvasive evaluation of coronary artery disease. Thirty-four patients with heart failure and/or severe mitral regurgitation were included. Three-dimensional reconstructions and standard orthogonal planes were used to assess CS anatomy and its relation with the MVA and circumflex artery. In 71 patients (68%), the circumflex artery coursed between the CS and the MVA with a minimal distance between the CS and the circumflex artery of 1.3+/-1.0 mm. The CS was located along the left atrial wall, rather than along the MVA, in the majority of the patients (ranging from 90% at the level of the MVA to 14% at the level of the distal CS). The minimal distance between the CS and MVA was 5.1+/-2.9 mm. In patients with severe mitral regurgitation, the minimal distance between the CS and the MVA was significantly greater as compared with patients without severe mitral regurgitation (mean 7.3+/-3.9 mm versus 4.8+/-2.5 mm, P<0.05).

CONCLUSIONS

In the majority of the patients, the CS courses superiorly to the MVA. In 68% of the patients, the circumflex artery courses between the CS and the mitral annulus. Multislice computed tomography may provide useful information for the selection of potential candidates for percutaneous mitral annuloplasty.

Whole-heart coronary vein imaging: A comparison between non-contrast-agent- and contrast-agent-enhanced visualization of the coronary venous system

The feasibility of three-dimensional (3D) whole-heart imaging of the coronary venous (CV) system was investigated. The hypothesis that coronary magnetic resonance venography (CMRV) can be improved by using an intravascular contrast agent (CA) was tested. A simplified model of the contrast in T(2)-prepared steady-state free precession (SSFP) imaging was applied to calculate optimal T(2)-preparation durations for the various deoxygenation levels expected in venous blood. Non-contrast-agent (nCA)- and CA-enhanced images were compared for the delineation of the coronary sinus (CS) and its main tributaries. A quantitative analysis of the resulting contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) in both approaches was performed. Precontrast visualization of the CV system was limited by the poor CNR between large portions of the venous blood and the surrounding tissue. Postcontrast, a significant increase in CNR between the venous blood and the myocardium (Myo) resulted in a clear delineation of the target vessels. The CNR improvement was 347% (P < 0.05) for the CS, 260% (P < 0.01) for the mid cardiac vein (MCV), and 430% (P < 0.05) for the great cardiac vein (GCV). The improvement in SNR was on average 155%, but was not statistically significant for the CS and the MCV. The signal of the Myo could be significantly reduced to about 25% (P < 0.001).

Importance of Anterograde Visualization of the Coronary Venous Network by Selective Left Coronary Angiography Prior To Resynchronization

BACKGROUND

Understanding of coronary anatomy is essential to the advancement of cardiac resynchronization therapy (CRT) techniques. We determined whether the difficulties associated with catheterization of the coronary sinus (CS) and its lateral branches could be overcome by a preliminary angiographical study of the coronary venous system carried out during a pre-operative coronary angiography with examination of venous return.

METHODS AND RESULTS

All patients were scheduled for an exploratory angiography procedure and indicated for CRT. Group A patients were implanted with a CRT device after a right arterial angiographical procedure while group B patients had a selective left angiogram including examination of venous return. Data analyzed in group B were: position of CS ostium, number and distribution of lateral branches, and ability to preselect a marginal vein suitable for catheterization. Subsequent device implantation was guided by these parameters. A total of 96 and 89 patients were included in groups A and B, respectively. Implantation success rates were not different (98% and 100%, respectively), but CS catheterization time was reduced in group B (6 minutes vs 4 minutes; P < 10(-6)) as well as total time required to position the left ventricular lead (25 minutes vs 15 minutes; P < 10(-6)), fluoroscopy exposure (7 minutes vs 5 minutes; P < 10(-6)), and volume of contrast medium required (45 mL vs 15 mL; P < 10(-6)).

CONCLUSION

A coronary angiographical study, including examination of the coronary venous return prior to implantation of a CRT device, can simplify the device implant and allows patient-specific preselection of appropriate tools for the procedure.

In Vivo Analysis of the Anatomical Relationship of Coronary Sinus to Mitral Annulus and Left Circumflex Coronary Artery Using Cardiac Multidetector Computed Tomography

OBJECTIVES

We sought to determine the in vivo anatomical relationships between mitral annulus (MA) and coronary sinus (CS) as well as CS and left circumflex coronary artery using cardiac computed tomography.

BACKGROUND

Percutaneous treatment of mitral regurgitation (MR) by annuloplasty via CS is under development. Success of such treatment depends on the close anatomical proximity of the MA to the CS. The in vivo data regarding this anatomical relationship in humans are scant. We investigated this relationship using contrast multidetector computed tomography.

METHODS

We studied 25 normal individuals and 11 patients with severe MR (3 to 4+) due to mitral valve prolapse. Separation between MA and CS was measured in standard planes, in 4-chamber (4C), 2-chamber (2C), and 3-chamber views. Distance from ostium of CS to the intersection with left circumflex (LCX), and anatomical relation of LCX and CS were determined using 3-dimensional mapping (Philips Brilliance, Philips Medical Systems, Amsterdam, the Netherlands).

RESULTS

There was significant variance of CS to MA separation at all planes. Separation of CS and MA was increased in lateral location (4C) and decreased in posterior location (2C) in the MR group with increase in MA size. Left circumflex artery crossed between CS and MA in 80% of patients. The LCX crossed CS at a variable distance from the ostium of CS (86.5 +/- 21 mm, range 37 to 123 mm)

CONCLUSIONS

There is significant variability in the relation of CS to MA in humans. Coronary sinus to MA distance increases in patients with severe MR and annular dilation, mainly in the posterolateral location. The left circumflex crosses under the CS the majority of times, but with a significant variability in the location where it crosses the CS. These anatomical features should be taken into consideration while selecting percutaneous treatment strategies for mitral valve repair.

Non-Invasive Visualization of the Cardiac Venous System in Coronary Artery Disease Patients Using 64-Slice Computed Tomography

OBJECTIVES

This study was designed to evaluate the value of 64-slice computed tomography (CT) to visualize the cardiac veins and evaluate the relation between variations in venous anatomy and history of infarction.

BACKGROUND

Cardiac resynchronization therapy (CRT) is an attractive treatment for selected heart failure patients. Knowledge of venous anatomy may help in identifying candidates for successful left ventricular lead implantation.

METHODS

The 64-slice CT of 100 individuals (age 61 +/- 11 years, 68% men) was studied. Subjects were divided into 3 groups: 28 control patients, 38 patients with significant coronary artery disease (CAD), and 34 patients with a history of infarction. Presence of the following coronary sinus (CS) tributaries was evaluated: posterior interventricular vein (PIV), posterior vein of the left ventricle, and left marginal vein (LMV). Vessel diameters were also measured.

RESULTS

Coronary sinus and PIV were identified in all individuals. Posterior vein of the left ventricle was observed in 96% of control patients, 84% of CAD patients, and 82% of infarction patients. In patients with a history of infarction, a LMV was significantly less observed as compared with control patients and CAD patients (27% vs. 71% and 61%, respectively, p < 0.001). None of the patients with lateral infarction and only 22% of patients with anterior infarction had a LMV. Regarding quantitative data, no significant differences were observed between the groups.

CONCLUSIONS

Non-invasive evaluation of cardiac veins with 64-slice CT is feasible. There is considerable variation in venous anatomy. Patients with a history of infarction were less likely to have a LMV, which may hamper optimal left ventricular lead positioning in CRT implantation.

Coronary sinus is dilated and outwardly displaced in patients with mitral regurgitation: Quantitative Angiographic analysis

OBJECTIVES

Our aim was to define the anatomy of the coronary sinus (CS) by venography. These measurements are essential in the selection of physical characteristics of percutaneous annuloplasty devices for mitral regurgitation (MR).

BACKGROUND

Clinical trials of percutaneous annuloplasty of the CS for MR are now underway. Although the CS is in close proximity to the mitral annulus, there is as yet no published quantitative data defining the magnitude of change in CS dimensions in MR, and how these changes might reflect the magnitude of MR.

METHODS

We studied 57 patients (27 patients with MR and 30 patients with no MR) who were referred for cardiac resynchronization therapy and underwent CS venography. Echocardiography was used to assess the degree of MR, cardiac dimensions, and right heart filling pressures. The diameter of the ostial and proximal CS and perimeter of the CS-great cardiac vein (GCV) were assessed by quantitative coronary analysis.

RESULTS

Patients with MR had a larger ostial CS diameter (19.4+/-3.9 mm vs. 16.9+/-4.6 mm, P=0.02) and proximal CS diameter (8.2+/-1.7 mm vs. 7.4+/-2.3 mm, P=0.05) and larger CS-GCV perimeter (104.4+/-15.6 mm vs. 86.5+/-15.3 mm, P=0.005) compared with patients with no MR. The CS-GCV perimeter is positively correlated to the severity of MR (P=0.02) and pulmonary artery pressure (r=0.32, P<0.05).

CONCLUSIONS

Patients with MR have a dilated and outward displacement of the CS. The CS-GCV perimeter is positively correlated with the degree of MR and pulmonary artery pressure.

Imaging of the Cardiac Venous System: Comparison of MDCT and Conventional Angiography

OBJECTIVE

Diagnostic and therapeutic strategies in electrophysiology and interventional cardiology include the coronary venous system. The purpose of this study was to compare MDCT angiography with conventional coronary sinus angiography in terms of detailed anatomic display of the coronary veins.

CONCLUSION

MDCT angiography is a reliable alternative to conventional coronary sinus angiography for detailed anatomic display of the coronary veins.

The Anatomic Barriers in the Coronary Sinus: Implications for Clinical Procedures

BACKGROUND

Coronary sinus (CS) catheterization is often used in cardiac resynchronization therapy. Failure to enter the CS is the most common reason for LV pacing lead implant failure.

METHODS

We evaluated the anatomic barriers, Thebesian and Vieussens valves, the CS and its tributaries in 52 adult human cadaver hearts.

RESULTS

The average diameter of CS ostiums was 9.47 mm. In 20 of the hearts heavier than 300 g, the average CS os diameter was 10.76 mm, whereas in the remaining hearts was 8.72 mm (p<0.005). The Thebesian valves were observed in 35(67%) of the hearts. In 39(75%) of the hearts Vieussens valves were observed and noted that 6(11%) of them were qualitatively well developed and 33(63%) diminutive. Twenty cases (38%) had 3 vein branches, 19(37%) had 4 branches, 6(11%) had 5 branches, 6(11%) had 2 branches and 1(2%) had 6 branches between great and middle cardiac veins. The anatomic barriers in coronary sinus i.e., Thebesian and Vieussens valves and their branchings were evaluated and found optimal, suboptimal and worst for catheterization in 33, 15 and 4 Thebesian valves; 40, 8, 4 Vieussens valves, respectively. The coronary sinus tributaries between great and middle cardiac veins were found to be optimal, suboptimal and worst for catheterization in 88, 60 and 38 veins, respectively.

CONCLUSIONS

Careful evaluation of anatomic barriers is important for treatment success. Thus, knowledge of these functional anatomic features and barriers allows for better utilization of the human coronary sinus for diagnostic and therapeutic purposes.

Noninvasive evaluation of cardiac veins with 16-MDCT angiography

OBJECTIVE

Anatomic mapping of the cardiac veins is important to guide transvenous therapeutic procedures such as biventricular pacing. As an alternative to invasive venography, we studied the feasibility of MDCT of the cardiac venous anatomy.

CONCLUSION

Cardiac venous anatomy is variable. MDCT is a noninvasive method that allows detailed imaging of the cardiac venous anatomy, including small cardiac veins and thebesian valves. Therefore, cardiac MDCT may be a valuable tool for guiding procedures that involve the cardiac venous system.

Coronary venous imaging with electron beam computed tomographic angiography: three-dimensional mapping and relationship with coronary arteries

BACKGROUND

The coronary venous system can provide vascular access for diagnostic and therapeutic procedures. Visualization of the coronary veins and their relationship to other cardiac structures may play an important role in facilitating these procedures. We sought to assess the ability of electron beam computed tomographic angiography (EBCTA) to characterize 3-dimensional (3-D) coronary venous anatomy.

METHODS

Two hundred thirty-one consecutive EBCTA coronary studies were analyzed. The coronary venous system was mapped and analyzed using 2- and 3-D images with definition of diameter and angulations of branch vessels and distance from CS os.

RESULTS

The coronary sinus (CS), great cardiac, middle cardiac, left ventricular (LV) anterior interventricular, LV marginal, LV posterior, left atrial, and right atrial veins were visualized in 100%, 100%, 100%, 100%, 78%, 81%, 6%, and 8% of the studies, respectively, with definition of diameter and angulations of branch vessels and distance from CS os. There was a significant linear correlation between CS diameter and right atrial end systolic volume (R = 0.244, n = 81, P < .05). No significant correlation existed between CS os diameter and other cardiac size or function parameters. The 3-D spatial arrangements between the coronary veins and the coronary arteries in relation to the epicardium were able to be defined, on the basis of the vessel closer to the epicardium in overlapping segments.

CONCLUSIONS

EBCTA can provide 3-D visualization of most components of the coronary venous system and definition of the spatial relationships with coronary arteries. EBCTA may potentially serve as a useful noninvasive tool for coronary venous imaging for procedures involving coronary veins, such as resynchronization therapy.

The Coronary Venous Anatomy

The coronary sinus is the gateway for left ventricular (LV) epicardial lead placement for cardiac resynchronization therapy. The implanting electrophysiologist is usually challenged by a high degree of variability in the coronary venous anatomy, making it important to have a more consistent and uniform segmental approach to describe the coronary venous tree and its branches. Classifying the coronary sinus branches and tributaries by the segment of their location rather than by conventional anatomic names (i.e., middle cardiac vein, great cardiac vein, and so on), would provide more relevant anatomic and functional information at the time of LV lead placement. This would enable the implanting physician to proactively correlate the venous anatomy with the segmental wall motion abnormalities or dyssynchrony, as defined by echocardiography and other imaging modalities. The current viewpoint calls for a more systematic segmental approach for describing the coronary venous anatomy.

Three-Dimensional Visualization of the Coronary Venous System Using Multidetector Row Computed Tomography

BACKGROUND

This study was undertaken to investigate the applicability and image quality of contrast-enhanced visualization of the coronary venous system (CVS) by multidetector row computed tomography (MDCT).

METHODS AND RESULTS

A total of 70 patients underwent MDCT and for each patient, 6 data sets were created throughout the cardiac cycle. The number and location of coronary veins were evaluated in 3-dimensional images using the 6 data sets. The quality of all images reconstructed from the 6 data sets was too poor to evaluate the CVS in 6 patients (9%). In the remaining 64 patients (91%), the diameter of the CVS was usually greater in the images reconstructed from data acquired during systole than in those reconstructed from data acquired during diastole. However, artifacts were observed more often in images from systole than from diastole. The coronary sinus and middle cardiac vein were visible in all 64 patients. The left marginal and posterior veins also were identified in 54 (84%) and 60 patients (94%), respectively.

CONCLUSIONS

MDCT can be used as a non-invasive modality for evaluating the CVS anatomy in most patients.

Thebesian Valve Imaging with Electron Beam CT Angiography:. Implications for Resynchronization Therapy

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.

Great cardiac vein variations

A novel variation in the relationship of the great cardiac vein to the circumflex artery was observed in an otherwise normal cadaver heart. Vessels originated and terminated normally, but in their midcourse they were twisted around each other such that each made one complete loop around the other. This variation did not seem to be involved in any pathologies. Variations in the course of the great cardiac vein have been little studied until recently, but their simplicity emphasizes the uniqueness of our intertwined case. Commonly, the great cardiac vein varies with respect to presence, location, and the superficial or deep relationship of single crossings of the anterior interventricular and circumflex arteries. Although rare, the intertwined variation described in the present case may have important basic science implications for understanding mechanisms of vasculo-angiogenesis, and clinical implications for catheter-based procedures and surgeries in the region of the coronary sulcus. Also, a review of great cardiac vein variations is presented herein.

Thebesian Valve Imaging with Electron Beam CT Angiography:. Implications for Resynchronization Therapy

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.