Echocardiographic evaluation of the coronary sinus

Giant Coronary Sinus Complicated by Spontaneous Thrombosis

Spontaneous coronary sinus thrombosis (CST) is an extremely rare occurrence. Most cases are iatrogenic and related to right heart instrumentation, due to either central line placement or electrophysiology procedures such as pacemaker insertion that causes direct damage to the endothelial lining. The course can be insidious and may result in a fatal outcome. Diagnosis of CST is challenging, and the syndrome often goes unrecognized. However, in the current era of multimodality imaging, it is possible that this condition will be recognized in more patients. Herein, we present a patient with spontaneous coronary sinus thrombosis that was diagnosed using multimodality imaging and thereafter successfully managed.

Optimized Computed Tomography Acquisition Protocol for Ethanol Infusion Into the Vein of Marshall

OBJECTIVES

This study sought to introduce a computed tomography (CT) protocol for optimal planning of vein of Marshall (VOM) catheterization.

BACKGROUND

Ethanol infusion into the VOM (Et-VOM) is increasingly used in atrial fibrillation ablation.

METHODS

Preprocedural CT was performed with either a conventional (conv-CT; n = 132) or an optimized CT protocol (VOM-CT; n = 126) designed for obtaining on a single image both left atrial and coronary sinus (CS) enhancement. The detection rate and anatomical features of the CT-derived VOM were analyzed and the utility of VOM-CT protocol was assessed by comparing the procedural data.

RESULTS

VOM was detected in 35% in conv-CT versus 63% in VOM-CT (P < 0.001). The VOM-CT protocol did not impair the assessment of left atrial anatomy and appendage patency. In VOM-CT, the detection of the VOM was related to body mass index and width of epicardial space on posterior wall. Mean distance between CS ostium and VOM was 36 ± 7 mm. Mean VOM diameter was 1.6 ± 0.3 mm. On the CS circumference, the VOM emerged superiorly in 68% and postero-superiorly in 32%. Ethanol infusion into the VOM was attempted in 165 patients (77 conv-CT, 70 VOM-CT, and 18 without-CT). After registration in CARTO, the VOM segmented on CT matched its location on venography in all cases. As compared with conv-CT and without-CT, procedures guided by VOM-CT showed significantly shorter radiation time, shorter procedure time, lower amount of the contrast medium, and fewer contrast injections to obtain VOM catheterization.

CONCLUSIONS

The proposed CT protocol allows for improved visualization of the VOM, translating into easier VOM catheterization.

Echocardiography for extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) provides advanced cardiopulmonary life support for patients in cardiac and/or respiratory failure. Echocardiography provides essential diagnostic and anatomic information prior to ECMO initiation, allows for safe and efficient ECMO cannula positioning, guides optimization of flow, provides a modality for rapid troubleshooting and patient evaluation, and facilitates decision-making for eventual weaning of ECMO support. Currently, guidelines for echocardiographic assessment in this clinical context are lacking. In this review, we provide an overview of echocardiographic considerations for advanced imagers involved in the care of these complex patients. We focus predominately on new cannulas and complex cannulation techniques, including a special focus on double lumen cannulas and a section discussing indirect left ventricular venting. Echocardiography is tremendously valuable in providing optimal care in these challenging clinical situations. It is imperative for imaging physicians to understand the pertinent anatomic considerations, the often complicated physiological and hemodynamic context, and the limitations of the imaging modality.

Coronary Sinus Ablation Is a Key Player Substrate in Recurrence of Persistent Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent atrial arrhythmia. During the last few decades, owing to numerous advancements in the field of electrophysiology, we reached satisfactory outcomes for paroxysmal AF with the help of ablation procedures. But the most challenging type is still persistent AF. The recurrence rate of AF in patients with persistent AF is very high, which shows the inadequacy of pulmonary vein isolation (PVI). Over the last few decades, we have been trying to gain insight into AF mechanisms, and have come to the conclusion that there must be some triggers and substrates other than pulmonary veins. According to many studies, PVI alone is not enough to deal with persistent AF. The purpose of our review is to summarize updates and to clarify the role of coronary sinus (CS) in AF induction and propagation. This review will provide updated knowledge on developmental, histological, and macroscopic anatomical aspects of CS with its role as arrhythmogenic substrate. This review will also inform readers about application of CS in other electrophysiological procedures.

Successful percutaneous coronary intervention significantly improves coronary sinus blood flow as assessed by transthoracic echocardiography

BACKGROUND

Transthoracic echocardiography (TTE) has been used to assess coronary sinus blood flow (CSBF), which reflects total coronary arterial blood flow. Successful angioplasty is expected to improve coronary arterial blood flow. Changes in CSBF after percutaneous coronary intervention (PCI), as assessed by TTE, have not been systematically evaluated.

HYPOTHESIS

TTE can be utilized to reflect increased CSBF after a successful, clinically indicated PCI.

METHODS

The study cohort included 31 patients (18 females, 62 ± 11 years old) referred for diagnostic cardiac catheterization for suspected coronary artery disease and possible PCI, when clinically indicated. All performed PCIs were successful, with good angiographic outcome. CSBF per cardiac cycle (mL/beat) was measured using transthoracic two-dimensional and Doppler flow imaging as the product of coronary sinus (CS) area and CS flow time-velocity integral. CSBF per minute (mL/min) was calculated as the product of heart rate and CSBF per cardiac cycle. In each patient, CSBF was assessed prospectively, before and after cardiac catheterization with and without clinically indicated PCI. Within- and between-group differences in CSBF before and after PCI were assessed using repeated measures analysis of variance.

RESULTS

Technically adequate CSBF measurements were obtained in 24 patients (77%). In patients who did not undergo PCI, there was no significant change in CSBF (278.1 ± 344.1 versus 342.7 ± 248.5, p = 0.36). By contrast, among patients who underwent PCI, CSBF increased significantly (254.3 ± 194.7 versus 618.3 ± 358.5 mL/min, p < 0.01, p-interaction = 0.03). Other hemodynamic and echocardiographic parameters did not change significantly before and after cardiac catheterization in either treatment group.

CONCLUSIONS

Transthoracic echocardiographic assessment can be employed to document CSBF changes after angioplasty. Future studies are needed to explore the clinical utility of this noninvasive metric.

Comparison of coronary sinus diameter Z-scores in normal fetuses and fetuses with persistent left superior vena cava (PLSVC)

To establish Z-score reference ranges for coronary sinus (CS) diameter in normal fetuses and explore the diagnostic value of CS Z-score in fetuses with persistent left superior vena cava (PLSVC). Study of 235 normal fetuses and 30 fetuses with PLSVC was involved. Noncardiac biometrical parameters included biparietal diameter (BPD), femoral length (FL), heart area (HA), gestation age (GA). The coronary sinus systolic and diastolic diameter (CSDs and CSDd ) were measured at the end of systole and diastole. CSDs and CSDd Z-score models were constructed by using linear regression analysis with Non-cardiac biometrical parameters as independent variables. Z-scores between normal fetuses and fetuses with PLSVC were compared. A simple, linear regression model was the best description and correlations between fetal CSDs and CSDd and four independent variables were excellent. Reference ranges for predicting means and SDs of the fetal CS were established. Equations for Z-score calculation were provided, CSDs and CSDd Z-scores were statistically different between normal fetuses and those with PLSVC. Development of CSDs and CSDd Z-score reference ranges in normal fetuses was realized. The CSDs and CSDd Z-scores can provide quantitative evidence in prenatal diagnosis of PLSVC.

Regression equations of Z score and echocardiographic nomograms for coronary sinus in healthy children

As the number of implanted biventricular pacemakers increases, the coronary sinus (CS) has evoked much interest amongst cardiologists. A dilated CS could prompt the existence of many diseases. The normal CS diameter is uncertain, especially in children. A total of 446 Chinese healthy children were prospectively enrolled in this study. The superior and inferior diameter of the CS was measured from the CS ostium 1 cm from the end of ventricular systole in the modified apical 4-chamber view. Seven models were tested to determine the relationships between parameters of body size and CS diameter. Heteroscedasticity was tested by the White and Breusch-Pagan tests. A multiple linear regression model should be gender as a covariate along with BSA_Stevenson, in order to evaluate the influence of gender on the measurements. The formula of Stevenson was best-fit. The predicted values and Z-score boundaries for measurement of the CS diameter were calculated. Bland-Altman plot regression showed that the 95 % limits of agreement for inter- and intra-observer measurements were not significantly different. We report new, reliable echocardiographic Z scores for the CS diameter derived from a large population of healthy Chinese children. The Z scores can be used in echocardiographic examinations.

Development of the cardiac venous system in prenatal human life

The human coronary sinus is an evolutionary modification of the terminal part of the left sinus horn. Anatomically, the coronary sinus is a short, broad vessel that runs along the coronary groove situated on the diaphragmatic surface of the heart. This structure, which opens into the right atrium, collects blood from the great cardiac vein and from other veins of the heart as well. In this study, we assessed the growth and dimensions of the coronary sinus at the fourth and eighth months of fetal development from whole material received from the Nicolaus Copernicus University, Collegium Medicum, Department of Histology and Embryology in Bydgoszcz. A group of 219 specimens, 105 male and 114 female fetuses, presented no visible malformations or developmental abnormalities. The results of this study determined that the dimension of the coronary sinus during prenatal development is not sexually dimorphic. Furthermore, following a monthly period of rapid growth in length of this structure, there are no further increases in length after the six months gestation. Finally, we concluded that the dimensions of the coronary sinus obtained during autopsy are similar to those determined through intravital ultrasound examination. The diameter of the coronary sinus is the best parameter to monitoring the fetal age and the growing of the fetus. Accordingly, we suggest that the best way of estimate for proper blood drainage from heart veins is study of coronary sinus volume.

Characterization of the coronary sinus ostium by cardiac magnetic resonance imaging

The diameter and the angle of the coronary sinus (CS) ostium was analyzed in 101 patients who underwent cardiac magnetic resonance imaging and had left ventricular ejection fractions < or =0.35 (n = 40) or > or =0.65 (n = 61). The angle of the CS ostium in patients with LVEFs < or =0.35 was less acute than in patients with LVEFs > or =0.65 (73 degrees +/- 12 degrees vs 65 degrees +/- 10 degrees, p <0.01). There was no statistically significant difference in the diameter of the CS ostium in patients with LVEFs < or =0.35 compared with those with LVEFs > or =0.65 (8 +/- 3 vs 8 +/- 2 mm, p = 0.5). The diameter and the angle of the CS ostium were not different when analyzed on the basis of the duration of the QRS complex, left atrial dimension, or left ventricular end-diastolic dimension. In conclusion, on the basis of cardiac magnetic resonance imaging data, the angle of the CS is less acute in patients with LVEFs < or =0.35 than in those with LVEFs > or =0.65.

Coronary Flow Reserve by Contrast Enhanced Transesophageal Coronary Sinus Doppler Measurements Can Evaluate Diabetic Microvascular Dysfunction

BACKGROUND

This study was undertaken to investigate whether coronary flow reserve (CFR) using coronary sinus flow (CSF), which can be measured by transesophageal Doppler echocardiography (TEDE), especially when contrast enhanced, is useful in evaluating microvascular dysfunction in patients with diabetes mellitus (DM).

METHODS AND RESULTS

CSF recordings using contrast enhanced TEDE were performed before and after adenosine triphosphate infusion (0.15 mg x kg(-1) x min(-1)) in 16 patients with type 2 DM and diabetic retinopathy and in 13 non-DM patients (control). Coronary angiography revealed normal epicardial coronary arteries. CFR was defined as the ratio of the antegrade flow velocity time integral in hyperemic conditions and basal levels. Clear envelopes of CSF were obtained in all DM patients using contrast-enhanced TEDE. CFR using CSF in the DM group was significantly decreased compared with the control group (1.4+/-0.4 vs 2.1+/-0.5, p<0.01), but there were no significant differences of age, ejection fraction, rate of hypertension and hypercholesterolemia between the 2 groups. Using 1.7 of CFR as the cut-off value, diabetic microvascular dysfunction could be detected with 82% sensitivity and 83% specificity.

CONCLUSIONS

CFR calculated by CSF using contrast-enhanced TEDE may be useful for evaluating diabetic microvascular dysfunction.

Caliber of the coronary sinus in fetuses with cardiac defects with and without left persistent superior vena cava and in growth-restricted fetuses with heart-sparing effect

OBJECTIVE

To assess reference ranges for fetal coronary sinus (CS) diameter and to compare them with values from fetuses showing heart defects with and without left superior vena cava (LSVC) as well as with severe intrauterine growth retardation and heart-sparing effect on color Doppler.

METHODS

The coronary sinus was visualized on two-dimensional ultrasound in a plane slightly caudal to the apical four-chamber view. For the normal range of the size of the CS in relation to gestational age, data was collected from 108/114 (95%) normal fetuses with good visualization between 20 weeks' gestation and term. Abnormal conditions comprised two groups: group 1 consisted of 52 fetuses with heart anomalies, including three subgroups: 11 fetuses with isolated LSVC emptying into the coronary sinus, 12 fetuses with LSVC associated with structural heart defects and 29 fetuses with structural heart defects but without LSVC. Group 2 consisted of 11 fetuses with severe intrauterine growth retardation and dilated coronary arteries as seen by color Doppler ultrasound.

RESULTS

Under normal conditions, there was a significant increase in the CS diameter with advancing gestational age (1.2-2.7 mm). Significant dilatation was found only in the two groups with LSVC (range 2.7-6.5 mm), independent of whether the finding was isolated or associated with cardiac defects.

CONCLUSION

CS visualization and measurements are easily feasible in the human fetus in the apical four-chamber view. Significant dilatation of the CS is a sign of LSVC. The examiner should be aware of this condition as such dilatation is commonly falsely diagnosed as atrial or atrioventricular septal defect.

Two-dimensional and M-mode echocardiography of the fetal coronary sinus

OBJECTIVE

To document fetal coronary sinus dimensions in normal pregnancy.

METHODS

Two hundred and sixty-five normal fetuses in which congenital cardiac defects had been excluded were examined cross-sectionally between 21 and 38 weeks of gestation. From the apical or basal four-chamber view the transducer was tilted towards the inferior cardiac surface in order to visualize the coronary sinus by real-time ultrasound. Maximum systolic and diastolic diameters were measured using M-mode. Reference ranges were constructed and the ratio of systolic and diastolic diameters calculated. Data from two fetuses, one with supraventricular tachycardia and a second one with hydrops secondary to anemia, were also compared.

RESULTS

Visualization and measurement of the coronary sinus were successful in 258 (97.4%) patients. The coronary sinus systolic and diastolic diameters increased significantly with gestational age (maximum systolic diameter, 1.6 mm at 21 weeks to 4 mm at 38 weeks; maximum diastolic diameter, 0.9 mm at 20 weeks to 2.2 mm at 38 weeks). The ratio of systolic to diastolic diameters remained relatively constant (range, 1.7-2.1) and therefore was unrelated to gestational age. In the fetuses with supraventricular tachycardia and hydrops, both diameters of the coronary sinus were increased and diminished fluctuation in size during the cardiac cycle was observed.

CONCLUSIONS

The described sonographic approach provides an effective method for measurement of coronary sinus dimensions. The normative data may facilitate the detection of coronary sinus dilation as an indirect marker for abnormalities in venous return to the heart.

Minimally invasive aortic valve replacement: echocardiographic and clinical results

BACKGROUND

Port access has been described for mitral and bypass surgery. The purpose of this study was to review the clinical and echocardiographic outcomes of aortic valve replacement by use of port access.

METHODS

Between 1996 and 1999, 153 port-access aortic valve replacements were performed at our institution. The mean age was 63 years (range 16-91 years); 58% were male. The New York Heart Association mean class was III; 18% were in class IV. Thirteen percent had diabetes, 42% hypertension, 7% prior transient ischemic episode or stroke, 7% lung disease, 3% renal failure, and 13% previous surgery. Echocardiograms were obtained after valve replacement in 125 patients (96 intraoperative transesophageal and 97 transthoracic echoes).

RESULTS

Median length of stay was 8 days. There were no intraoperative deaths; 10 patients (6.5%) died in the postoperative period. Stroke occurred in 4 (2.6%), sepsis in 5 (3.3%), renal failure in 5 (3.3%), pneumonia in 3 (2%), and wound infection in 1 (0.7%). Tissue prosthesis was present in 83 and a mechanical prosthesis in 42. No or trace regurgitation was seen on 94 of 96 (98%) postbypass intraoperative echocardiograms and mild on 2. On follow-up echocardiograms, moderate regurgitation was seen in 4 of 97 (4.1%), mild-to-moderate in 2 (2.1%), mild in 18 (18.6%), and no or trace in 71 (73.2%). Of those who had aortic regurgitation on intraoperative or follow-up echocardiograms, it was paravalvular in 8.

CONCLUSIONS

Minimally invasive aortic valve replacement with a port-access approach is feasible, even in high-risk patients. Small incisions, a low infection rate, and a short length of stay are attainable. However, the complications associated with traditional aortic valve replacement still occur. Echocardiography is valuable both for intraoperative monitoring and follow-up of this new procedure.

Measurement of coronary sinus flow using transesophageal echocardiography in patients undergoing coronary artery bypass grafting

STUDY OBJECTIVE

To measure coronary sinus blood flow during coronary artery bypass graft (CABG) with transesophageal echocardiography (TEE).

DESIGN

Prospective study.

SETTING

Elective cardiac surgery at a university hospital.

PATIENTS

Thirty-one ASA physical status III and IV adult patients free of significant coexisting disease and undergoing CABG.

INTERVENTION

We measured coronary sinus blood flow velocity by using TEE and hemodynamic variables, before and after cardiopulmonary bypass (CPB) and after CPB.

MEASUREMENTS AND MAIN RESULTS

We obtained a complete set of control measurements for 29 subjects (94%) and a complete set of post-CPB measurements in 28 patients (90%). In the normal group, peak velocity, and velocity time integral (VTI) of coronary sinus blood flow in the post-CPB period increased significantly compared with the pre-CPB period with CABG (n = 23). In the group of new regional wall motion abnormalities in the post-CPB period, peak velocity and VTI of coronary sinus blood flow in the post-CPB period did not increase significantly compared with the pre-CPB period by CABG (n = 5).

CONCLUSIONS

We were able to measure the coronary sinus flow velocity by pulse-Doppler TEE during CABG. The peak velocity and VTI of coronary sinus blood flow in the post-CPB period increased significantly compared with in the pre-CPB period by CABG. The results of this preliminary study show the feasibility of clinical evaluation of CABG intraoperatively.

The Role of Transesophageal Echocardiography During Port-Access Minimally Invasive Cardiac Surgery: A New Challenge for the Echocardiographer

The recent development of endovascular catheters that are placed via the femoral artery and vein has enabled patients to be placed on cardiopulmonary bypass without the need for direct visualization of the heart or great vessels via sternotomy. This has allowed cardiac surgery to be performed through smaller, thoracotomy incisions. Placement of these catheters initially was performed under fluoroscopic guidance, which has major imaging limitations. Now, transesophageal echocardiography (TEE) has replaced fluoroscopy as the primary imaging technique to assist in the placement of endovascular catheters during minimally invasive, port-access cardiac surgery. In our institution, 449 port-access procedures have been performed from May 1996 through July 1998. We found that TEE is able to adequately visualize the cardiac structures and assist in the placement of the endovascular catheters in all patients. Fluoroscopy is helpful only as an aid to the use of TEE for placement of the coronary sinus catheter.

Utility of transesophageal echocardiography during port-access minimally invasive cardiac surgery

In this study, we sought to determine the use of transesophageal echocardiography (TEE) as the primary imaging technique to assist in the placement of endovascular catheters during minimally invasive, port-access cardiac surgery. The recent development of endovascular catheters that are placed via the femoral artery and vein has enabled patients to be placed on cardiopulmonary bypass without the need for direct visualization of the heart or great vessels via sternotomy. This has allowed cardiac surgery to be performed through smaller thoracotomy incisions. Placement of these catheters has previously been performed with fluoroscopic guidance, which has major imaging limitations. Thirty-six patients underwent port-access cardiac surgery at our institution during the study period. All patients underwent intraoperative TEE. We used TEE to visualize the coronary sinus os, right atrium and superior vena cava, and thoracic aorta to assist with placement of the coronary sinus catheter, venous cannula, and endoaortic clamp. Twenty patients underwent mitral valve surgery, 14 patients coronary artery bypass grafting, 1 patient aortic valve replacement, and 1 patient repair of an atrial septal defect by the port-access approach. TEE was able to adequately visualize the cardiac structures and assist in the placement of the endovascular catheters in all patients. Fluoroscopy was only helpful as an aid to TEE for placement of the coronary sinus catheter. TEE is an excellent imaging modality for the proper placement of these new endovascular catheters, obviating the need for fluoroscopy, except to be on standby and for placement of the coronary sinus catheter.

Anatomy of atrioventricular nodal reentry investigated by intracardiac echocardiography

Intracardiac echocardiography was used to evaluate posteroseptal space anatomy in patients with atrioventricular nodal reentrant tachycardia compared with patients with other mechanisms of tachycardia. The posteroseptal space was found to be significantly wider in patients with atrioventricular nodal reentry, suggesting an anatomic basis for dual atrioventricular nodal physiology.