Imaging of the coronary venous system in patients with congestive heart failure: comparison of 16 slice MSCT and retrograde coronary sinus venography: Comparative imaging of coronary venous system

Association of Difference in Coronary Sinus Diameter by Computed Tomographic Angiography Between Patients in and Not in Stable Atherosclerotic Plaque(S)

Background

Pathological finding fail to describe the morphology of coronary arterial plaques. Retrograde cardiac arteriography is a complicated procedure and does not detect all left posterior and marginal veins of the heart. Magnetic resonance angiography has long scan time and low spatial resolution. The objective of the present study was to assess the possible utility of the difference in coronary sinus diameter to quantify stable atherosclerotic plaque(s) using 256-slice coronary computed tomographic angiography.

Material/Methods

A total of 336 patients were divided into 2 groups with 168 patients each. Patients who had heart failure were included in the study group and those who did not were included in the non-study group. Patients were subjected to cross-sectional study. Cardiovascular images were performed with 256-slice coronary computed tomographic angiography with a prospective electrocardiogram and clinical manifestation. Two-tailed paired t test following Dunnett’s multiple comparison tests was performed for the quantitative measurement of coronary computed tomographic angiography and clinical manifestation at 99% confidence level.

Results

The clinical manifestation did not clearly show cardiac abnormality. The diameters of the superoinferior coronary sinus ostium was than that of the anteroposterior coronary sinus ostium, (p<0.0001, q=26.325). There was the difference in size of the coronary sinus ostium between patients in and not in heart failure (p<0.0001). The study group patients had longer coronary sinuses than patients in the non-study group (p<0.0001).

Conclusions

256-slice computed tomographic angiography is a feasible and is non-invasive bio-tool for evaluation of coronary artery anatomy.

The Role of Cardiovascular Magnetic Resonance in Cardiac Resynchronization Therapy

Randomized, controlled trials have shown that cardiac resynchronization therapy (CRT) is beneficial in patients with heart failure, impaired left ventricular (LV) systolic function, and a wide QRS complex. Other studies have shown that targeting the LV pacing site can also improve patient outcomes. Cardiovascular magnetic resonance (CMR) is a radiation-free imaging modality that provides unparalleled spatial resolution. In addition, emerging data suggest that targeted LV lead deployment over viable myocardium improves the outcome of patients undergoing CRT. This review explores the role of CMR in the preoperative workup of patients undergoing CRT.

The Role of Cardiovascular Magnetic Resonance in Cardiac Resynchronization Therapy

Randomized, controlled trials have shown that cardiac resynchronization therapy (CRT) is beneficial in patients with heart failure, impaired left ventricular (LV) systolic function, and a wide QRS complex. Other studies have shown that targeting the LV pacing site can also improve patient outcomes. Cardiovascular magnetic resonance (CMR) is a radiation-free imaging modality that provides unparalleled spatial resolution. In addition, emerging data suggest that targeted LV lead deployment over viable myocardium improves the outcome of patients undergoing CRT. This review explores the role of CMR in the preoperative workup of patients undergoing CRT.

Introducer Development for Coronary Sinus Access From Parasternal Mediastinotomy

OBJECTIVE

Right parasternal mediastinotomy with right atriotomy has been used clinically for pacemaker insertion. A similar approach might facilitate access to the coronary sinus for biventricular pacing and other manipulations when more conventional approaches are not feasible. The primary barrier to this is lack of appropriate introducers and techniques.

METHODS

Anatomically derived introducers were developed in 2 anesthetized domestic pigs using data from computerized axial thoracic tomography. Each digitized tomogram defined a unique introducer shape and was constructed using 3-dimensional (3D) modeling software and printing. Each parent pig then underwent surgery demonstrating coronary sinus lead insertion, using its custom-configured introducer. Next, with institutional review board approval, 65 patients were identified who had undergone conventional endocardial coronary sinus lead insertion followed by thoracic scanning. These tomograms were used to design appropriately curved introducers for human anatomy.

RESULTS

Fifty-one introducer paths were defined following anatomic pathways and avoiding bends inconsistent with materials used for commercial peel-away introducers. Each path was defined by a bend and distance toward the coronary sinus ostium and a hook and twist out of plane to align with the local orientation of the coronary sinus. The average dimensions were the following: distance, 67 mm; bend angle, 47 degrees; hook angle, 39 degrees; and twist angle, 20 degrees. A prototype cannula was tested for fit in a fresh frozen postmortem human specimen.

CONCLUSIONS

Parasternal mediastinotomy access to the coronary sinus for cardiac resynchronization, mitral annuloplasty, and instrumentation is feasible. Human computerized tomographic scans can be used to define curvatures and dimensions for marketed introducers.

Assessment of the coronary venous system using 256-slice computed tomography

Purpose

To investigate the coronary venous system and its relation to adjacent structures using 256-slice computed tomography (CT).

Materials and Methods

The study consisted of 102 patients who underwent coronary CT angiography (CTA) using 256-slice CT. For each patient, the coronary venous system and its relation to adjacent structures were evaluated. The appropriate locations and diameters of the posterior interventricular vein (PIV), posterior vein of the left ventricle (PVLV) and the left marginal vein (LMV) were detected. The paired student's t test was used to evaluate the difference between the diameter of the coronary sinus (CS) ostium in anteroposterior direction and that in superoinferior direction.

Results

The CS, great cardiac vein (GCV), PIV, and anterior interventricular vein (AIV) were visualized in all cases. It was possible to evaluate at least one main vein with adequate caliber and regular course for cardiac resynchronization therapy (CRT) in 96.1% of these cases. The diameter of the CS ostium in superoinferior direction (11.7±2.1 mm) was larger than that in anteroposterior direction (9.0±2.0 mm) (t = 13.511, P<0.05). For the majority of the cases, the CS-GCV was located above the level of the mitral valve annulus (MVA), while the left circumflex coronary artery (LCX) was coursed between the CS-GCV and the MVA. LMV had more intersection with the circumflex or circumflex marginal than PVLV.

Conclusion

256-slice CT provides superior noninvasive evaluation of the coronary venous system which has important clinical implications.

Cardiac CT: Imaging of and Through Cardiac Devices

For patients with cardiac devices, cardiac computed tomography (CT) remains the mainstay for imaging due to its superior resolution as compared with echocardiography and nuclear studies and no contraindication to metal as with cardiac magnetic resonance imaging. This review focuses on the evaluation and pitfalls of coronary arterial imaging in patients with devices, such as pacemakers, implantable defibrillators, cardiac resynchronization therapy (CRT), as well as complications such as lead perforation and safety concerns of CT interference. We discuss both pre- and post-procedural CRT assessment for coronary venous imaging and pre-procedural myocardial scar assessment to localize regions of scar and peri-infarct zone to facilitate ventricular tachycardia ablation in patients with devices. We describe potential new research on dyssynchrony and integration with myocardial scar and site of latest activation for patients with or being considered for CRT. We detail the utility of CT for the assessment of proper function and complications in patients with left ventricular assist device implantation.

Novel tips for engaging the coronary sinus guided by right ventricular lead

AIMS

This study investigated the relationship between the ostia of the coronary sinus (CS) and the tricuspid annulus (TA) for CS cannulation using a right ventricular (RV) lead, which could map out the TA by forming a curve when placed at the apex or low septum.

METHODS AND RESULTS

Seventy patients (45 males, 67 ± 12 years) who were admitted for CRT device implant were included in the evaluation of the relationship between the CS ostia and TA. An electrophysiological (EP) mapping catheter was used to probe the CS. The ostium was shown by the CS venography at the left anterior oblique (LAO) 20° and caudal 20°. Local electrograms were collected with CS catheters in the CS or RV. Transthoracic echocardiography was evaluated before each procedure. All CS ostia were located within 3.75 cm around the tip of TA. Sixty-two subjects (Group I, 89%) had CS ostia located under the TA. Eight patients (Group II) with CS ostia over the TA revealed larger left ventricular (LV) size and a smaller ratio of left atrium (LA)/LV size. LV enlargement predicted the presence of CS ostia over the TA. Typical CS electrograms were used to further confirm if the EP catheter was in the CS in all the subjects.

CONCLUSION

Use of the RV lead revealed that the CS ostia had a close relationship with the TA.

Contrast-enhanced whole-heart coronary MRA at 3.0T for the evaluation of cardiac venous anatomy

This study was designed to evaluate the value of contrast-enhanced whole-heart coronary MRA (CMRA) at 3.0T in depicting the cardiac venous anatomy. In cardiac resynchronization therapy (CRT), left ventricular (LV) pacing is achieved by positioning the LV lead in one of the tributaries of the coronary sinus (CS). Pre-implantation knowledge of the venous anatomy may help determine whether transvenous LV lead placement for CRT is feasible. Images of 51 subjects undergoing contrast-enhanced whole-heart CMRA at 3.0T were retrospectively analyzed. Data acquisition was performed using electrocardiography-triggered, navigator-gated, inversion-recovery prepared, segmented gradient-echo sequence. A 32-element cardiac coil was used for data acquisition. The visibility of the cardiac veins was graded visually using a 4-point scale (1: poor–4: excellent). The paired Student t test was used to evaluate differences in diameters of the ostium of the CS in anteroposterior and superoinferior direction. The cardiac veins were finally evaluated in 48 subjects with three anatomic variations. The diameter of the CS ostium in the superoinferior direction (1.13 ± 0.26 cm) was larger than in the anteroposterior direction (0.82 ± 0.19 cm) (P < 0.05). The mean visibility score of CS, posterior interventricular vein, posterior vein of the left ventricle, left marginal vein, and anterior interventricular vein was 4.0 ± 0.0, 3.4 ± 0.5, 3.4 ± 0.5, 3.0 ± 0.8, and 3.3 ± 0.5, respectively. In conclusion, contrast-enhanced whole-heart CMRA at 3.0T can depict the normal and variant cardiac venous anatomy.

Accuracy and usefulness of fusion imaging between three-dimensional coronary sinus and coronary veins computed tomographic images with projection images obtained using fluoroscopy

AIMS

Coronary sinus (CS) and coronary veins are not delineated by fluoroscopy. The study evaluates the feasibility and accuracy of cardiac tomography (CT) image registration of CS anatomy on fluoroscopic image.

METHODS AND RESULTS

Eighteen consecutive patients underwent contrast-enhanced, ECG-gated CT scanning. Coronary sinus, coronary veins, superior vena cava, the distal portion of the trachea, and of the two main bronchi were reconstructed. These images were then fused over the CS fluoroscopic angiogram. Registration accuracy was verified by assessing the overlap of CS borders both in the CT- and in the fluoroscopy-derived images. The mean distance between the centrelines of the CS was 0.73 mm, with a maximum distance of 2.22 mm. For the first-order branches, mean distance was 0.80 mm with a maximum distance of 2.64 mm. High Lin concordance correlation coefficients were computed (>0.95) for the CS and first-order branch diameters, although the Bland and Altman limits were large. The agreement between the number of vessels identified was moderate with kappa = 0.43.

CONCLUSION

Fusion imaging processing of two different imaging modalities (CT and fluoroscopy) may be feasible and accurate for guiding CRT implantation as it allows constant comprehensive display of CS body and branches. Prospective studies are needed for assessing clinical implications.