the coronary venous system: an alternative route of access to the myocardium

The purpose of this paper is to review what is known regarding the anatomy of the coronary venous system, and the commonly used techniques for its selective catheterization. This is with regard to new innovative percutaneous techniques that have led to a burgeoning interest in methods of access to the coronary veins. Anatomical variation in the epicardial system exists, and the additional role of the Thebesian venous system may have important clinical implications. Catheter-based techniques for coronary vein retroperfusion may provide alternative treatment modalities for patients with no option for revascularization using conventional techniques. Furthermore, the use of the coronary venous system has now been reported for the regional delivery of drugs, cells and genes to protect and/or regenerate the myocardium. Finally, the use of the coronary venous system by the cardiac electrophysiologist is reviewed.     

Radiofrequency ablation of an epicardial ventricular tachycardia through the great cardiac vein in a patient with mitro-aortic mechanical prostheses.

AIMS: Prior cardiac surgery limits epicardial ventricular tachycardia (VT) ablation due to epicardial adhesions formation. METHODS AND RESULTS: We describe an epicardial VT ablation through the coronary venous system in a patient with mechanical mitro-aortic prostheses. The different possible ablation approaches and their potential limitations are discussed. CONCLUSION: In selected patients, especially after cardiac surgery, coronary venous system approach can be considered as a safety possible approach for the ablation of some epicardial VTs.     

冠状静脉窦系统在电生理应用及其影像学评价

对于心脏血流循环,人们多关注冠状动脉系统,近年来伴随着射频消融术及心脏再同步化治疗在临床的广泛应用,冠状静脉窦系统越来越受到重视和关注,但冠状静脉窦系统解剖变异较大,因此应用前对其形态、位置等进行评价显得相当重要,近些年来影像学迅速发展,如多层螺旋CT已成为临床诊断不可缺少的工具,从而为冠状静脉窦系统的评价提供了新的手段,现将综述冠状静脉窦系统的影像学评价及在电生理的应用。     

Optimal image reconstruction using multidetector‐row computed tomography to facilitate cardiac resynchronization therapy

Preprocedural recognition of the segment of latest mechanical contraction along with the anatomy of the coronary venous system is important for successful and effective cardiac resynchronization therapy. We present a case of ischemic cardiomyopathy who underwent implantation of a cardiac resynchronization therapy device with a defibrillator, which was facilitated by preprocedural computed tomographic images reconstructed to visualize the left ventricular slab and the coronary venous system simultaneously on the cardiac contour. The present reconstruction method using computed tomography is optimal and feasible method to incorporate the echocardiographic findings into the procedure performed under fluoroscopy appropriately.     

Transcatheter Coronary Sinus Interventions

The coronary sinus has become a popular route for an increasing number of innovative transcatheter interventions to treat coronary and structural heart diseases. However, interventional cardiologists have limited experience with the cardiac venous system and its highly variable anatomy. In this paper, we review the anatomy of the cardiac veins as it relates to transcatheter interventions. We also provide a contemporary overview of the emerging coronary sinus–based transcatheter therapies and their growing literature.     

Human Coronary Venous Anatomy: Implications for Interventions

The coronary venous system is a highly variable network of veins that drain the deoxygenated blood from the myocardium. The system is made up of the greater cardiac system, which carries the majority of the deoxygenated blood to the right atrium, and the smaller cardiac system, which drains the blood directly into the heart chambers. The coronary veins are currently being used for several biomedical applications, including but not limited to cardiac resynchronization therapy, ablation therapy, defibrillation, perfusion therapy, and annuloplasty. Knowledge of the details of the coronary venous anatomy is essential for optimal development and delivery of treatments using this vasculature. This article is part of a JCTR special issue on Cardiac Anatomy.     

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.     

The efferent cardiac lymphatic pathways in the macaque monkey.

In ten postmortem hearts of the Macaque monkey (M. mulatta), the coronary lymphatics were visualized using an India ink suspension in 2% gelatin. The left coronary lymphatic initially passed to the dorsal surface of the aortic arch. In five hearts, this lymphatic went directly to the cardiac lymph node, whereas in the others, it first ascended to the left superior tracheobronchial node and then interconnected with the cardiac lymph node. The right coronary lymphatic usually passed in front of the ascending aorta and common arterial (brachiocephalic) trunk and entered the cardiac lymph node. In two hearts, however, the right coronary lymphatic first ascended to an anterior transverse mediastinal node and from here lymphatics joined the cardiac lymph node. Those lymphatics that passed cephalad from the cardiac lymph node to the right anterior mediastinal nodes and the right paratracheal nodes ultimately emptied into the right venous angle. Those lymphatics that passed cephalad from the cardiac lymph node to the anterior transverse mediastinal nodes ultimately emptied into the left venous angle. In five other Macaque monkeys (M. mulatta and M. fascicularis) after marker injection (T1824 blue dye and micropulverized barium sulfate) into the living heart or pericardium, lymphatic drainage beyond the base of the heart could not be demonstrated. Whereas postmortem morphologic studies suggest that the monkey coronary lymphatic system is amenable to obstruction by removal of the cardiac lymph node and interruption of its adjacent lymphatic connections, effective methods for visualizing the mediastinal lymphatic collecting system in the living monkey must be developed before experimental cardiac lymphatic ablation can be accomplished in this species.     

Alternate pathways to pulmonary venous flow in left-sided obstructive anomalies.

In cardiac anomalies causing severe obstruction in the left side of the heart, such as aortic atresia, mitral atresia, or occasionally severe aortic stenosis, maintenance of circulation depends upon shunting of pulmonary venous blood into the right atrium. The usual pathway by which the shunt is achieved is across the atrial septum through the foramen ovale. When this route is closed or severely narrowed, alternate but less common pathways may exist. These involve either anomalous connections of pulmonary veins to systemic veins or communications with the coronary venous system. In the latter, as commonly occurs in aortic atresia, left ventricular myocardial sinusoids carry pulmonary venous blood from the left ventricular cavity and into the cardiac veins. In other instances of severe left-sided obstruction, a direct communication may exist between the left atrium and the coronary sinus.     

The coronary venous anatomy: a segmental approach to aid cardiac resynchronization therapy

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.     

Morphologic and topologic characteristics of coronary venous system delineated by noninvasive multidetector computed tomography in chronic systolic heart failure patients

BackgroundVariations of coronary venous system in a dilated, failing heart may well be unpredictable. Noninvasive preview of coronary veins before left ventricular (LV) lead implantation for cardiac resynchronization therapy would facilitate successful procedure in chronic systolic heart failure (SHF) patients.Methods and ResultsMultidetector computed tomography (MDCT) of the heart was investigated in 23 consecutive patients of chronic SHF with LV ejection fraction ≤40%. Morphologic and topologic characteristics of coronary venous system were studied, and compared with 23 age-matched controls. All coronary veins including coronary sinus, posterior interventricular vein (PIV), LV posterior vein, left margin vein (LMV), and anterior interventricular vein (AIV) were clearly visible in all 23 SHF patients and 23 normal controls. Total coronary venous length (ie, from PIV to AIV) was directly correlated with LV volume (r = 0.65, P < .001). The main lengthened venous segment was between LMV and AIV. Ostial diameters of all coronary venous tributaries were larger in SHF patients, but the angle of branching was similar. However, the secondary angle of the coronary sinus relative to superior vena cava axis was more acute (30 ± 7°) in SHF patients than that in normal (44 ± 8°, P < .001). Local aneurysm locating at LV posterolateral wall could detour relevant coronary vein tributaries to the outer border of the aneurysm, compress venous dimensions throughout the cardiac cycle, and cause acute angulation of venous tributaries.ConclusionsCoronary venous system shown by MDCT in SHF patients with low LV ejection fraction manifested longer venous length between LMV and AIV, acute secondary CS angle, and usually topologically distorted by posterolateral LV aneurysms. A panoramic delineation of all coronary venous tributaries could help effective venous intervention.     

Technical failure to perform cardiac resynchronization therapy: use of cardiac magnetic resonance imaging techniques to clarify a left-sided superior vena cava and coronary sinus morphology

The most common reason for failure to implant a left ventricular lead to deliver cardiac resynchronization therapy is the presence of unfavourable coronary venous anatomy. The present report illustrates the use of cardiac magnetic resonance imaging to delineate the anatomy of a left-sided superior vena cava in two patients in whom permanent cardiac pacing was unattainable.     

Retrograde coronary venous contrast echocardiography: assessment of shunting and delineation of regional myocardium in the normal and ischemic canine heart

Coronary venous injections of sonicated Renografin-76 were performed in seven closed chest dogs during two-dimensional echocardiography to study the ability of this new technique to opacify regional myocardium before and after occlusion of the left anterior descending coronary artery. The balloon of a 4F double lumen catheter was inflated in the great cardiac vein for each contrast injection to prevent backflow through the coronary sinus into the right atrium. Retrograde injections before coronary artery occlusion generally resulted in patchy myocardial contrast uptake. Injections after coronary occlusion always resulted in confluent and transmural myocardial opacification which occupied 42.8 +/- 8.6% (range 26 to 54) (mean +/- standard deviation) of the myocardial circumference. Retrograde opacification always extended into adjacent myocardium beyond the ischemic zone, which was assessed in echocardiograms with antegrade contrast injections into the left main coronary artery and which measured 30 +/- 6.3% of the ventricular circumference. Shunting from the coronary venous system to cardiac chambers was evaluated in a parasternal four chamber view and was graded on a scale of 0 to 4+. Contrast appearance was equally intense in the right atrium and right ventricle (3.5 +/- 0.6+, range 2+ to 4+), less intense in the left ventricular cavity (1.5 +/- 0.6+, range 1+ to 3+) and absent in the left atrium. Postmortem anatomic validation with retrograde great cardiac vein injections of indocyanine green corroborated and in vivo contrast appearance in chambers. Retrograde coronary venous contrast echocardiography appears capable of providing in vivo information about the extent and location of myocardial zones that can be reached by retrograde infusions of therapeutic agents and about the ability of these agents to reach ischemic myocardium. In addition, this new method allows for in vivo evaluation of shunts between coronary veins and cardiac chambers, which may influence the efficacy of retrograde interventions.     

Myocardial revascularization with arterial conduits: comparison of bilateral internal mammary artery and single internal mammary artery

The use of bilateral internal mammary artery (BIMA) grafting for myocardial revascularization has been demonstrated to provide long-term benefits compared to revascularization using single left internal mammary artery (SIMA) and venous conduits. However, it is still controversial whether the use of BIMA is associated with a higher hospital mortality and morbidity. The present study retrospectively evaluated the possible advantages related to the use of BIMA at 3-year follow-up and whether the presence of operative risk factors in patients with BIMA could limit the application of the procedure in myocardial revascularization. We compared two groups of 100 patients matched for preoperative clinical characteristics, who underwent myocardial revascularization on the left coronary system with BIMA (93 males and 7 females, mean age 59 +/- 4 years) or with SIMA and venous conduits (86 males and 14 females, mean age 63 +/- 6 years). Hospital mortality rate was 2% in both groups, the use of BIMA being not a significant risk factor for hospital mortality and morbidity. The mean follow-up was 36 +/- 6 months for the BIMA group and 40 +/- 10 months for the SIMA group. At 3 years, there was no significant differences in the actuarial freedom from cardiac death (96 +/- 2% for BIMA vs 94 +/- 2% for SIMA patients), myocardial infarction (98 +/- 2 vs 97 +/- 2%), angina (93 +/- 2 vs 91 +/- 2%), symptomatic heart failure (92 +/- 3 vs 92 +/- 2%), coronary angioplasty/reoperation (96 +/- 2 vs 97 +/- 2% ), and total cardiac events (80 +/- 4 vs 76 +/- 4%). BIMA grafting was not an independent predictor of late cardiac events. In 66 patients who underwent a late angiographic or echo-Doppler study, the patency rate was 100% for the left mammary artery, 94% for the right mammary artery and 69% for venous conduits. In conclusion, myocardial revascularization with BIMA in situ is associated with low hospital mortality and morbidity, good clinical outcome and excellent patency rate at 3 years, with apparently no significant differences when compared to the use of SIMA and venous conduits. The low hospital mortality and morbidity and the satisfactory medium-term results in our opinion justify a more extensive use of BIMA in myocardial revascularization.     

Percutaneous valve repair for mitral regurgitation using the Carillon Mitral Contour System. Description of the method and case report

Mitral regurgitation may result from left ventricular dilatation and cause progression of heart failure. Percutaneous techniques for mitral valve repair are under development. Techniques utilizing a trans-coronary venous approach exploit the anatomical relationship between the mitral annulus and the venous system of the heart. The coronary sinus, great cardiac vein and the origin of the anterior interventricular vein surround the posterior mitral annulus. This enables percutaneous approaches to annuloplasty for mitral regurgitation. Devices can be implanted into the coronary veins that modify the shape and size of the mitral annulus. We present a case of ischaemic mitral regurgitation successfully treated by use of a percutaneous approach, the Carillon Mitral Contour System. Significant reduction of the mitral regurgitation jet was observed. The patient was discharged 4 days after the procedure. During the follow-up visits, the patient showed an improved general condition and increased exercise capacity. Procedural steps are shown in detail and the current status of the coronary sinus based technique is discussed. Percutaneous techniques for mitral valve repair may be an attractive alternative to cardiac surgery in heart failure patients with secondary mitral regurgitation. The Carillon Mitral Contour System is under ongoing clinical evaluation in the AMADEUS trial.     

Untersuchungen zur kardialen Endothelin-Freisetzung in den Koronarsinus bei Myokardisch?mie und koronarem Endotheltrauma

Endothelin has both vasoconstrictor and mitogenic properties and might, therefore, play a role in the pathogenesis of acute coronary syndromes and coronary atherosclerosis. The aim of the study was to characterize the mechanisms and kinetics of cardiac endothelin-1 (ET-1) release following a local endothelial injury during PTCA (group A) and after sustained myocardial ischemia (group B). Additionally, the precision of agreement between measurements in coronary sinus and peripheral venous samples should be analyzed. In group A, elective PTCA was performed in 20 patients with stable angina pectoris and a > 70% type A stenosis. Simultaneous determinations of ET-1 from coronary venous and peripheral venous blood were done before balloon inflation and during the several hours following the last dilatation procedure. A coronary sinus study with high rate atrial pacing was performed in 20 group B patients with coronary multivessel disease. ET-1 was determined from coronary sinus and peripheral venous blood samples prior to stimulation and during several hours after cessation of pacing. Control groups were provided for both groups. The control group consisted of 10 patients with coronary angiography without PTCA for group A and 10 patients with angiographic normal coronary arteries for group B.PTCA induced an instantaneous increase of coronary sinus ET levels from 4.1 +/- 1.1 pg/ml to 13.7 +/- 2.3 pg/ml (peripheral venous 7.9 +/- 2.5 pg/ml), which was more pronounced if the target vessel was the left anterior descending artery. This peak was followed by a gradual decrease of ET-1 to the limit of normal within 6 hours. The concentrations of ET, furthermore, remained higher in the coronary sinus compared with the peripheral vein indicating a persisting cardiac release of ET.In group B, incremental atrial pacing resulted in myocardial ischemia, and a significant increase in ET-1 from 4.6 +/- 0.6 pg/ml to 13.1 +/- 2.8 pg/ml was detected in the coronary sinus samples. A persistent cardiac release of ET-1, as reflected by sustained elevated coronary sinus concentrations, was observed for up to one hour after cessation of pacing. The analysis of measurement agreement between coronary venous and peripheral venous samples revealed considerable variations of the differences between the two sampling sites indicating wide limits of agreement. Despite a significant positive correlation, our date reflecting a remarkable lack of agreement. CONCLUSIONS: 1) An enhanced release of ET-1 following PTCA is mainly due to the localized endothelial injury, and the ET-1 levels remain elevated for up to hours after the mechanical stimulus. 2) A short-lasting myocardial ischemia is associated with a significant ET-1 increase. 3) For refined evaluations of release kinetics of cardiac ET-1, blood sampling from the coronary sinus seems to be essential.     

Percutaneous approach to a stent-based ventricle to coronary vein bypass (venous VPASS): comparison to catheter-based selective pressure-regulated retro-infusion of the coronary vein.

AIMS: Percutaneous stent-based ventricle-to-coronary vein bypass (venous VPASS) is a new approach to chronic venous arterialization as a treatment modality in an otherwise no option patient with coronary artery disease. In this study, the efficacy of venous VPASS was compared with catheter-based selective pressure-regulated retro-infusion of arterial blood during acute ischaemia. METHODS AND RESULTS: In seven pigs, venous VPASS was established using a percutaneous ultrasound-guided puncture from the anterior cardiac vein to the left ventricle, with subsequent implantation of an ePTFE-covered stent graft. During left anterior descending artery (LAD) occlusion, coronary venous pressure in the distal anterior cardiac vein increased to 55+/-4 mmHg under conditions of venous VPASS compared with 78+/-5 mmHg during selective pressure-regulated retro-infusion. Significant preservation of regional myocardial function was observed during venous VPASS (67+/-6% baseline) and during selective retro-infusion (83+/-4%) compared with control LAD occlusion (0.4+/-2%). CONCLUSION: Percutaneous implantation of a PTFE covered stent (venous VPASS) was feasible and associated with significant preservation of regional myocardial function during acute ischaemia in pigs at reasonable levels of mean coronary venous pressure to avoid tissue damage during chronic application.     

Intravenous obsidan-induced changes of coronary venous blood flow in patients with coronary heart disease in the presence of transient myocardial ischemia]

Intravenous obsidan was evaluated for its effects on the blood flow in the coronary sinus and the major cardiac vein in 23 coronary heart disease patients with hyperkinetic central hemodynamics. The use of the drug was found to be effective when the patients had had high baseline coronary venous blood flow. At the peak of cardiac pacing, the patients with low coronary sinus blood flow on obsidan showed decreased blood flow in the ischemic myocardial portions, developed signs of left ventricular failure and diminished anginal threshold. Those with moderate baseline blood flow on obsidan displayed an insignificant increase in anginal threshold, higher blood flow was inadequate to oxygen consumption.     

Effective cryoablation of a lateral accessory pathway within the distal coronary sinus

Limited information is available on the efficacy of cryoablation in the coronary venous system in humans. A patient with a lateral accessory pathway was referred to our center after several unsuccessful endocardial and epicardial (within the coronary sinus) attempts using standard radiofrequency energy. Ablation was subsequently performed successfully by applying cryoenergy distally into the coronary sinus, using a temperature of -50 degrees C and a freezing application time of 45 s. There were no complications. Angiography of the left coronary circumflex artery and coronary venous system was performed at 12 months follow-up using cardiac multislice computed tomography, and no coronary stenosis or anatomic anomaly was found. Neither pre-excitation or any arrhythmia recurred during follow-up. This experience suggests that ablating in the distal coronary sinus can be safely performed using cryoenergy.     

Effect of the intravenous administration of finoptin on coronary venous blood flow in patients with ischemic heart disease

Intravenous finoptin (verapamil), 10 mg, was tested for effects on the coronary venous blood flow by probing the coronary sinus and great vein of the heart and performing atrial pacing in 24 patients with ischemic heart disease and eukinetic central hemodynamics. In persons who had had initial high blood flow in the coronary sinus, the agent was found to induce resting coronary venous blood flow changes which were inadequate for its demand and during cardiac pacing; whereas in patients with mean initial venous blood flow values, finoptin enabled myocardial oxygen consumption to be provided both in the region of non-infarcted myocardium and in the ischemic area.