Coronary sinus filling time: a novel method to assess microcirculatory function in patients with angina and normal coronaries

OBJECTIVE

Dysfunction of the coronary microcirculation is considered as one of the factors responsible for symptoms and abnormal stress tests in patients with angina and normal coronaries (syndrome X). We sought to evaluate the usefulness of coronary sinus filling time (CSFT) to assess coronary microcirculation in this group of patients.

METHODS

We compared the CSFT of patients having definite angina or atypical angina with positive treadmill electrocardiography test (angina group), with that of patients undergoing coronary angiogram (CAG) prior to balloon mitral valvuloplasty (control group). During CAG, coronary sinus was visualized in appropriate views and CSFT in seconds was derived from frame count. Thrombolysis In Myocardial Infarction (TIMI) flow grade, corrected TIMI (cTIMI) frame count, TIMI Myocardial Perfusion grade (TMP) were assessed.

RESULTS

There were 41 patients in angina group and 16 in control group. Among the angina group 68.8% were females as against 81.8% in the control group. 87.8% (n = 36) had typical angina. Mean CSFT was 4.25 ± 0.72 s and 3.46 ± 0.99 s in the angina group and control group respectively (p = 0.001). No significant differences were found between the groups with respect to TMP (p = 0.68) & cTIMI frame count (p = 0.22).

CONCLUSION

CSFT is a simple method to assess the transit time through coronary microcirculation. CSFT was significantly delayed in patients with angina and normal coronaries. TMP and cTIMI frame count were not significantly different between groups.

Coronary sinus draining into the left subclavian vein through a persistent left superior vena cava

A persistent left superior vena cava (PLSVC) is formed by the remains of the oblique vein of the left atrium, which is not completely degenerated during embryonic development. The incidence is approximately 0.3% in the general population. Approximately 80-92% of PLSVCs drain into the right atrium through the coronary sinus. This report describes a rare case of PLSVC in which the coronary sinus (CS) did not open into the right atrium, but rather drained into the left subclavian vein through the PLSVC.

Coronary sinus anatomy by computerized tomography, overlaid on live fluoroscopy can be successfully used to guide left ventricular lead implantation: a feasibility study

OBJECTIVE

This study aims to optimize coronary sinus (CS) computerized tomography (CT) imaging and evaluate its utility for preprocedural planning and intraoperative guidance by overlay of 3D reconstructed CS images on live fluoroscopy.

BACKGROUND

Optimal CS lead placement for cardiac resynchronization therapy (CRT) remains challenging. Preprocedural knowledge of CS anatomy can significantly affect procedural outcome. Optimal CS imaging protocols by CT have not been well defined.

METHODS

Seventeen consecutive CRT recipients underwent contrast-enhanced functional cardiac CT on a 64-slice scanner. The CS target branch closest to the most dyssynchronous LV segment was identified. 3D volume rendered CS images were superimposed onto live fluoroscopy via EP Navigator (Philips Healthcare, Best, The Netherlands) to guide CS cannulation and lead placement. The imaging protocol was optimized.

RESULTS

CT images were successfully reconstructed and overlaid on live fluoroscopy in 16/17 patients. The overlay facilitated CS cannulation and lead placement into a predefined target branch. Excellent correlation between CT and angiographic CS anatomy was noted. By using the overlaid 3D CS as a road map, average total fluoroscopy time (14.56 ± 4.22 min) was significantly shorter when compared to historical controls. Total radiation exposure was significantly higher in the CT-guided group. Images obtained using double bolus injection and gated acquisition at 40 % of the cardiac cycle contained the most anatomical detail of the CS.

CONCLUSION

Overlay of 3D CS anatomy defined by preprocedural cardiac CT is feasible. It allows planning of CRT implantation and live guidance of CS lead placement into a predefined target branch. Limiting the CT imaging to 40 % of the cardiac cycle phase provides optimal CS images and reduces radiation exposure. This approach may result in shorter procedural time and more optimal CS lead positioning. However, the concept remains to be confirmed by future studies.

Cardiac tamponade due to rupture of coronary artery fistula to the coronary sinus with giant aneurysm of coronary artery: usefulness of transthoracic echocardiography

A 68-year-old woman was admitted to our hospital because of back pain and syncope. Transthoracic echocardiography revealed pericardial effusion, a collapsed right ventricle, a giant aneurysm connected to the coronary sinus, a dilated left main trunk coronary artery, and a dilated left circumflex artery (LCx). Furthermore, there was a coronary artery fistula arising from the LCx that drained into the coronary sinus. We diagnosed cardiac tamponade due to rupture of the coronary artery fistula or giant aneurysm, and successful emergency surgery was performed. Rupture of coronary artery aneurysm or coronary artery fistula is very rare. Transthoracic two-dimensional echocardiography was very useful in our case for the diagnosis of cardiac tamponade, giant coronary aneurysm, and coronary artery fistula.

Catheter migration after fracture is not always in right cavities

Catheter fracture and cardiac migration are rare but known complications. To our knowledge, this is the second reported case of catheter migration into the coronary sinus. The broken fragment was successfully retrieved using helical basket, whereas biplane fluoroscopy was helpful in the heart chambers because of a difficult spatial orientation. No complications were noted during or after this procedure.

Right coronary artery to coronary sinus fistula

Coronary arteriovenous fistulas are very uncommon. We present a case of a very large right coronary artery to coronary sinus fistula, ultimately leading to congestive heart failure and necessitating surgical intervention.

Intraoperative diagnosis of unroofed coronary sinus after aortic valve replacement

A patient with combined aortic insufficiency and stenosis underwent aortic valve replacement. After weaning off cardiopulmonary bypass, a new shunt into the left atrium was noted that had not been apparent on multiple previous echocardiographs. Using an agitated saline test, we confirmed a shunt between the coronary sinus and left atrium. The assumption was made that there had been an iatrogenic fistula created with placement of the retrograde catheter; however, upon opening the left atrium it was realized that the patient had a previously undiagnosed, congenitally unroofed coronary sinus. It was repaired primarily and the patient had an uneventful recovery.

Reduced antegrade flow in the coronary sinus is a predictor of coronary artery stenosis in hypertensive patients

OBJECTIVES

The purpose of this study was to evaluate the feasibility of assessing blood flow in the coronary sinus by transthoracic Doppler echocardiography for detecting coronary artery stenosis in hypertensive patients.

METHODS

Flow in the coronary sinus was studied in 105 participants who all had undergone coronary angiography: 35 nonhypertensive patients, 34 hypertensive patients without coronary artery disease (CAD), and 36 hypertensive patients with CAD. The antegrade phase of flow in the coronary sinus was analyzed and compared among the groups. Multivariate analysis for blood flow and coronary artery stenosis was done.

RESULTS

Compared with the nonhypertensive patients, the hypertensive patients without CAD had significantly higher blood flow (9.36 ± 5.94 vs 5.84 ± 2.91 mL/stroke and 584.45 ± 177.32 vs 327.68 ± 125.48 mL/min, respectively; P < .001) in the coronary sinus. Compared with the hypertensive patients without CAD, those with CAD had significantly lower blood flow (5.18 ± 0.72 vs 9.36 ± 5.94 mL/stroke and 352.51 ± 156.18 vs 584.45 ± 177.32 mL/min; P < .001) and a lower velocity time integral (13.14 ± 2.51 vs 19.85 ± 4.89 cm; P < .01). Stepwise multiple regression analysis indicated that the coronary sinus diameter, velocity time integral, and heart rate significantly correlated with the blood flow per minute in the coronary sinus in each group, and the flow per minute was the independent determinant of the percent stenosis diameter. The sensitivity, specificity, and accuracy for the prediction of severe stenosis (>70%) in the left coronary artery were 91.07%, 87.76%, and 88.49% for blood flow of less than 220 mL/min in the coronary sinus.

CONCLUSIONS

Transthoracic Doppler echocardiography can effectively depict blood flow changes in the coronary sinus, and reduced antegrade flow is a sensitive and specific predictor of coronary artery stenosis in hypertensive patients.

Rare case of an unroofed coronary sinus

Unroofed coronary sinus (CS) is a rare congenital cardiac anomaly described by a communication between the CS and the left atrium due to the partial or complete absence of the CS roof. Echocardiography is the most widely used imaging modality for suspected unroofed CS, but it is limited in its ability to visualize the posterior cardiac structures. Multidetector computed tomography has allowed the visualization and accurate anatomic and morphologic evaluation of these structures. We report a rare case of unroofed CS found incidentally in a 41-year-old man who was studied by echocardiography and multidetector computed tomography.

Evaluating adult cor triatriatum with total anomalous pulmonary venous connections by multidetector computed tomography angiography

A 19-year-old female patient was admitted to our hospital with dyspnea, chest pain, and shortness of breath. A chest radiograph showed mild cardiomegaly. Echocardiography revealed an extra chamber in the heart. To evaluate this abnormality, ECG-gated 16-detector-row computed tomography angiography was performed. Multidetector computed tomography (MDCT), showing cor triatriatum with total anomalous pulmonary venous connections (TAPVC), clearly revealed cardiac and vascular anatomy. ECG-gated cardiac MDCT is a useful tool for detection and characterisation of cor triatriatum and related anomalies.

Local coronary flow is associated with an unsuccessful complete block line at the mitral isthmus in patients with atrial fibrillation

BACKGROUND

The addition of a mitral isthmus (MI) block line after pulmonary vein isolation could lead to a favorable outcome of catheter ablation in patients with atrial fibrillation (AF). However, it is sometimes tough to create a complete MI block line, and the cooling effect because of the local coronary flow may prevent the creation of a successful MI block line.

METHODS AND RESULTS

This study enrolled 81 AF patients in whom the creation of an MI block line was attempted in those with persistent or pacing-inducible AF after pulmonary vein isolation. A local coronary artery (LCA) across the MI block line was observed in 43 (53%) of 81 patients, and a bidirectional MI block was successfully accomplished in 53 (65%) of 81 patients, at the estimated MI line. The ratio of a successful MI block line was significantly lower in the patients with an LCA than in those without an LCA (42% versus 92%; P<0.001). The mean diameter of the coronary sinus (0.59 ± 0.18 versus 0.82 ± 0.22 cm; P<0.001) and length of the estimated MI line (33.4 ± 9.9 versus 29.4 ± 7.1 mm; P=0.032) were significantly shorter in the patients with a successful MI block line than in those without a successful MI block line. In the multivariable analysis, an LCA at the MI and a larger coronary sinus diameter were independent risk factors for an unsuccessful MI block line.

CONCLUSIONS

Local coronary flow at the MI is associated with an increased incidence of an unsuccessful MI block line.

Quality of visualization of coronary venous system in 64-slice computed tomography

BACKGROUND

Multi-slice computed tomography (MSCT) can be used to visualize the anatomy of the coronary venous system (CVS). A pre-procedural evaluation of target veins is a very important element of cardiac resynchronization. Thus, the quality of visualization of the CVS is of great importance. The aim of this study was to analyze the quality of visualization of CVS in MSCT.

METHODS

In 220 subjects (129 male, average age 57.2 ± 11.8 years), a 64-slice CT (Aquilion 64, Toshiba, Japan) was performed. A scan with ECG-gating was performed using a slice thickness of 0.5 mm during a breath-hold. In each case, 3D volume rendering and 2D MPR reconstructions were created (Vitrea 2). The quality of visualization was graded independently by two cardiologists and a radiologist trained in MSCT on a 0-5 points scale for the coronary sinus and main veins [0 = not visible (lack of vein); 5 = visible as a smoothly bordered vascular structure].

RESULTS

The best visualization of the CVS was obtained for coronary sinus (4.10 ± 1.08), the worst for antero-lateral vein (2.11 ± 1.10). The average number of visible veins was 3.2 per case. Statistically, more veins were visible in older subjects - in the group aged 60+ the average number of visible veins was 3.6 ± 1.1 per case, whereas in those aged under 60 it was 2.9 ± 1.2 (p = 0.0001). There were no statistical gender differences in the quality of CVS visualization.

CONCLUSIONS

The target veins for cardiac resynchronization therapy should be the lateral and postero-lateral, which are usually well visible. Such a strategy could increase the usefulness of MSCT.

Imaging of persistent left sided superior vena cava with echocardiography and multi-slice computed tomography: implications for daily practice

Persistent left sided superior vena cava is a congenital abnormality encountered not uncommonly by the echocardiographer or cardiac radiologist. Recognition of its presence is important in the differential diagnosis of dilatation of the coronary sinus. We discuss the echocardiographic and computed tomography findings of this congenital abnormality, and the implications for clincal practice.

Giant coronary sinus

WEB SITE FEATURE

Characterization of the mechanical properties of the coronary sinus for percutaneous transvenous mitral annuloplasty

The coronary sinus (CS) vessel serves as a conduit for the deployment of percutaneous transvenous mitral annuloplasty (PTMA) devices for the treatment of functional mitral regurgitation. Characterization of the mechanical response of the CS is an important step towards an understanding of tissue-device interaction in PTMA intervention. The purpose of this study was to investigate the mechanical properties of the porcine CS using the pressure-inflation test and constitutively model the wall behavior using a four fiber family strain energy function (SEF). The results showed that the CS exhibited an S-shaped pressure-radius response and could be dilated up to 88% at a pressure of 80mmHg. Excellent results from model fitting indicated that the four fiber family SEF could capture the experimental data well and could be used in future numerical simulations of tissue-device interaction. In addition, a histological study was performed to identify the micro-structure of the CS wall. We found a high content of striated myocardial fibers (SMFs) surrounding the CS wall, which was also mainly composed of SMFs, while the content of smooth muscle cells was very low. Elastin and collagen fibers were highly concentrated in the luminal and outer layers and sparsely distributed in the medial layer of the CS wall. These structural and mechanical properties of the CS should be taken into consideration in future PTMA device designs.

Use of a low profile ultrasound transducer for coronary sinus cannulation: a pilot study

BACKGROUND

Cardiac resynchronization therapy with biventricular pacing has been shown to be beneficial in improving heart failure in patients with prolonged QRS duration (≥120 ms) and low ejection fraction (≤35%). Unsuccessful cannulation of the coronary sinus (CS) has been reported in up to 10% of cases. The feasibility of the transthoracic continuous cardiac imaging for coronary sinus cannulation has not been previously demonstrated.

METHODS AND RESULTS

We developed a 2.5-MHz hemi-spherical continuous cardiac imaging transducer (CONTISON), mounted in an external housing, to permit steering in 360°. The transducer was attached to the chest wall using an adhesive ring. The CS was easily imaged by echocardiography by placing the transducer just medial to the apex and tilting it dorsally. The feasibility study was done in 11 patients. CS ostium and body were imaged in all patients. Cannulation was successfully achieved in nine patients with a mean cannulation time of 1 minute 16 seconds. In two patients, poor image quality precluded adequate visualization of CS. Fluoroscopy was not used for cannulation.

CONCLUSION

We demonstrated the feasibility of using the CONTISON echography transducer for the guidance CS cannulation. This technique could expedite CS cannulation and reduce radiation exposure. Further studies comparing ultrasound versus fluoroscopy for CS cannulation appear warranted.

Two-stent telescoping technique for securing an atrially embolized venous stent

Coronary sinus stenosis or atresia is a rare problem in congenital heart disease. It is sometimes associated with ventricular dysfunction. In this setting, relief of the obstruction may improve myocardial perfusion and contractility. During percutaneous stent deployment within the coronary sinus, distal embolization of the stent into the atrial chambers occurred. The patient had double inlet left ventricle, severe ventricular dysfunction, interrupted IVC, mechanical aortic valve, and a Fontan circulation. The intervention was performed as a rescue procedure prior to transplantation referral. In this report we describe use of telescoping technique, i.e., deploying the distal end of a long stent within the embolized stent while traversing its proximal end across the stenosed coronary sinus ostium. This secured the embolized stent and at the same time relieved the coronary sinus stenosis.

An initiative to minimize amount of contrast media utilizing a novel rotational coronary sinus occlusive venography technique with ordinary cath-lab X-ray machine during CRT implantation

BACKGROUND

Rotational angiography is one of the latest angiographic modalities to map the coronary venous tree anatomy. It provides a significant reduction in both contrast agent usage and radiation dose (up to 30%), without compromising the clinical utility of images. Hence, the present study was conducted to describe a new technique to minimize the amount of contrast media used during cardiac resynchronization therapy (CRT) implantation.

METHOD

The SL3 sheath was inserted into the right atrium via the femoral vein followed by withdrawal of the dilator. The tip of the sheath was manipulated to the vicinity of the coronary sinus (CS) ostium (OS). The CS was entered using a deflated balloon catheter. The sheath was then advanced gently beyond the CS OS. Occlusive venography was performed using 5-8 ml of contrast media in a rotational view starting from 45 degrees LAO to 0 degrees AP while holding the inflated balloon for a few seconds.

RESULT

Data from 30 consecutive patients who underwent CRT implantation were analyzed. The feasibility of rotational angiography, while occluding the CS with a specialized long, preshaped sheath and using an ordinary cath-lab imaging machine, was supported by the correctly delineated CS anatomy of all patients without any complications and death related to the placement of the CS catheters or sheaths. The mean contrast dose used for the entire procedure in all patients undergoing CRT was 14.76 +/- 6.8 ml.

CONCLUSION

Use of rotational CS occlusive venography utilizing an ordinary cath-lab X-ray machine minimizes the use of contrast media during CRT implantation without compromising the visualized anatomy.

Traversing and dilating venous collaterals: a useful adjunct in left ventricular electrode placement

In patients receiving cardiac resynchronization therapy (CRT), the left ventricular electrode cannot always be positioned in the preferred lateral or posterolateral locations due to technical factors and anatomic variations in the coronary sinus. Recent reports also suggest that CRT outcomes are improved by pacing the site of latest dyssynchrony and accessing these regions is not always possible. We report the utility of applying a technique described in the interventional literature over the past 3 years, effectively traversing and dilating collateral channels. Our patients demonstrated either no venous targets in the optimal location, or problems accessing this location using a antegrade approach. Subsequently, collaterals supplying this region were traversed with a guidewire using a retrograde approach and dilated with a balloon catheter. In the first case, the pacing electrode was then advanced in similar fashion and successfully positioned in an ideal lateral location. In the second case, the retrograde guidewire was captured with a vascular snare and pulled into a second guiding catheter, allowing appropriate dilatation and stenting of a problematic proximal venous stenosis with resultant facile placement of the pacing electrode. This technique offers a potential alternative to patients with challenging venous anatomy as a method to facilitate optimal CRT outcomes.

Right coronary artery anatomical variants: where and how?

BACKGROUND

Ectopic origin of the right coronary artery (RCA) occurs in approximately 1.0% of studied populations. We investigated the prevalence and location of ectopic RCAs among patients undergoing coronary angiography (CA) and assessed its effects on resource utilization.

METHODS

Cases of ectopic RCAs were prospectively collected over 21 months among patients undergoing cardiac catheterization at a University Hospital. "Ectopic RCA" was defined as a RCA originating outside the posterior two-thirds of the right coronary sinus.

RESULTS

The study population included 2,120 patients, of which 23 (1.1%) had ectopic RCAs. Of these, 15 (65%) originated from the anterior third of the right sinus, while 8 (35%) originated from the anterior half of the left sinus. Mean procedure and fluoroscopy times were 60 +/- 33 and 15 +/- 12 minutes (min) for the former, and 78 +/- 35 and 31 +/- 20 min for the latter, while mean contrast volume for CA was 112 +/- 62 ml and 192 +/- 85 ml, respectively. 26% required a second CA or a second intervention to image the RCA.

CONCLUSION

Ectopic RCAs pose a clinical problem, consuming time and resources. The search for an ectopic RCA should have < 90 degree boundaries limited to the anterior third of the right sinus and anterior half of the left sinus.

Feasibility of cardiac resynchronization therapy in a patient with complex congenital heart disease and dextrocardia, facilitated by cardiac computed tomography and coronary sinus venography

We describe a case with pacemaker implantation for cardiac resynchronization therapy (CRT) in a patient with complex congenital heart disease, facilitated by cardiac computed tomography (CT) and coronary sinus (CS) venography. A 37-year-old male presented with congenitally corrected transposition of the great arteries and mesocardia, along with a history of two open heart surgeries (closure of atrial septal defects and a ventricular septal defect, and pulmonary valvectomy at age 7; mechanical tricuspid valve replacement at age 13). He showed symptoms of progressive heart failure (NYHA class III) with significant impairment of the systemic right ventricular function. He also developed permanent atrial fibrillation with a junctional rhythm at a rate of 45 beats per minute. Biventricular pacing without an atrial lead was considered to be the best option available. CRT implantation was facilitated by proper identification of CS anatomy utilizing cardiac CT and CS venography and was performed without any complications. At follow up, a postero-anterior chest X-ray showed the final position of the right-sided ventricular (left ventricular morphology) lead pointing to the apex and the left ventricular lead at the posterolateral aspect of the systemic ventricle (right ventricular morphology).

Rotational coronary sinus venography and magnetic navigation to facilitate LV lead placement in cardiac resynchronization therapy

This report demonstrates the production and use of 3-D reconstruction of a coronary sinus from a single-injection rotational angiogram. The detailed virtual model enabled easy magnetic navigation of a wire for device placement in cardiac resynchronization therapy.

The role of cardiovascular computed tomographic angiography for coronary sinus mitral annuloplasty

BACKGROUND

The coronary sinus (CS) travels in close proximity to the left circumflex (LCX) artery. Percutaneously placed CS devices used to treat mitral regurgitation (MR) therefore have the potential to impinge upon the LCX arterial distribution and compromise coronary flow.

OBJECTIVES

In this study, we sought to analyze the anatomic relationship between the CS, LCX and mitral annulus (MA) in patients with right dominant (RCD), left dominant (LCD) and codominant (CCD) arterial systems using a novel systematic approach.

METHODS

We retrospectively studied 102 normal patients (46 females) and 27 consecutive patients (5 females) with ischemic severe MR. All patients underwent cardiovascular computed tomographic (CCT) angiography with a 64 multidetector scanner for clinical indications. Images were analyzed using a GE Advantage workstation, version 4.4, capable of advanced image processing and manipulation.

RESULTS

In patients with a normal mitral valve, the LCX initially crossed under the coronary sinus/great cardiac vein (CS/GCV) in 74% with RCD, 83% with LCD and 97% with CCD. In patients with ischemic severe MR, the LCX initially crossed under the CS/GCV in 96%.

CONCLUSIONS

The majority of patients, especially those with a CCD, have the LCX initially coursing under the CS/GCV. CCT data analysis using our newly established method is an excellent tool to evaluate the anatomic course of the LCX in patients being evaluated for percutaneous CS device placement.

Single coronary artery originating from the right coronary sinus

WEB SITE FEATURE

[Venous system of the heart in chronic heart failure]

The intravital and posthumous changes of the venous system of the heart were studied in patients with chronic heart failure (CHF). Using the method of computer spiral tomography, the increase of the diameter of subepicardial and anterior cardiac veins, as well as of the coronary sinus, was detected that correlated with the stages of heart failure development. The increase of a total thickness of the veins wall at the expense of tunica media was recorded at the initial stages of CHF, which was later followed by the decrease of wall thickness due to the development of connective tissue.

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.

Double superior vena cava: right connected to left atrium and left to coronary sinus

Left persistent superior vena cava connected to coronary sinus may coexist with right superior vena cava connected to left atrium. Surgical correction is not mandatory if there is no cyanosis due to a big interjugular bridging vein.