Coronary Sinus Anomalies Research Articles

Coronary Sinus Anomalies with Case Illustrations

Abstract Coronary sinus (CS) is the largest coronary vein that receives blood from all the venous tributaries of the heart. Its variations in anatomy are significant from the surgical point of view, especially in patients with complex congenital heart diseases (CHDs). CS anomalies are rare, but with increasing advancements in imaging, they are often diagnosed with cardiac computed tomography (CT). These are associated with other CHDs, so the radiologists are alerted to look further for different anomalies. The data in this study were collected from the routine contrast-enhanced CT examinations of the patients referred to the Department of Radiology, Narayana Hrudayalaya Hospital, Bengaluru, from January 2019 to August 2023. It was observed that the anomalies were seldom seen as a single entity and instead were seen as a part of the spectrum of anomalies such as persistent left superior vena cava (LSVC), Raghib complex, total anomalous pulmonary venous connection, and interrupted inferior vena cava. Out of these, the most common associated anomaly was found to be persistent LSVC. These anomalies are essential to detect in the preoperative assessment because they may cause significant morbidity in some cases if left uncorrected. Therefore, we must search for other cardiac anomalies when encountering CS anomalies.

Incidence and appearances of coronary sinus anomalies in adults on cardiac CT.

The aim of this study was to analyze the frequency and appearances of coronary sinus (CS) anomalies on cardiac computed tomography (CT) of adult patients and to compare them with transthoracic echocardiography (TTE) findings. We retrospectively evaluated cardiac CT images for the presence of CS anomalies in 6936 adult patients who underwent imaging from April 1 2008 to March 31 2015 at our institution. We also reviewed and compared with TTE findings for the cases of CS anomalies. CS anomalies were diagnosed in 23 of the 6936 (0.33%) and included persistence of the left superior vena cava (PLSVC) in 19 cases, unroofed CS (UCS) in two, coronary artery-CS fistula in two, and CS atresia in one. TTE revealed CS dilatation in only five of the 16 cases of PLSVC and suggested CS anomaly in the two cases of coronary artery-CS fistula. The other cases of CS anomaly were detected incidentally on CT. The incidence of CS anomalies was 0.33%. Precise diagnosis of CS anomalies with TTE and the original transverse images on cardiac CT alone was difficult for some conditions. We should be alert for the presence of CS anomalies which can cause clinical or procedural complications.

Computed tomography and magnetic resonance imaging of the coronary sinus: anatomic variants and congenital anomalies.

The coronary sinus (CS) is an important vascular structure that allows for access into the coronary veins in multiple interventional cardiology procedures, including catheter ablation of arrhythmias, pacemaker implantation and retrograde cardioplegia. The success of these procedures is facilitated by the knowledge of the CS anatomy, in particular the recognition of its variants and anomalies. This pictorial essay reviews the spectrum of CS anomalies, with particular attention to the distinction between clinically benign variants and life-threatening defects. Emphasis will be placed on the important role of cardiac CT and cardiovascular magnetic resonance in providing detailed anatomic and functional information of the CS and its relationship to surrounding cardiac structures. Teaching Points • Cardiac CT and cardiovascular magnetic resonance offer 3D high-resolution mapping of the coronary sinus in pre-surgical planning.• Congenital coronary sinus enlargement occurs in the presence or absence of a left-to-right shunt.• Lack of recognition of coronary sinus anomalies can lead to adverse outcomes in cardiac procedures.• In coronary sinus ostial atresia, coronary venous drainage to the atria occurs via Thebesian or septal veins.• Coronary sinus diverticulum is a congenital outpouching of the coronary sinus and may predispose to cardiac arrhythmias.

Catheter ablation of an epicardial accessory pathway via the middle cardiac vein

Radiofrequency catheter ablation (RFA) of Wolff-ParkinsonWhite syndrome can be challenging and is associated with failure in up to 5% of cases. The main causes for initial failure were difficulties in catheter manipulation, inadequate accessory pathway (AP) mapping primarily due to epicardial or parahisian localization, and multiple pathways or insertions. Epicardial APs are most commonly found in the posteroseptal (PS) and left posterior regions. This kind of epicardial AP results from a connection between an extension of the coronary sinus (CS) myocardial coat along the middle cardiac vein (MCV), posterior coronary vein (PCV), or the neck of a CS anomaly and left ventricular epicardium. Therefore, they can be successfully ablated only from inside the CS or its branches, if endocardial ablation fails. A 19-year-old female with recurrent supraventricular tachycardia was referred for an electrophysiologic study (EPS). The ECG demonstrated ventricular preexcitation indicating PS-AP (Figure A). After induction of the orthodromic atrioventricular reciprocating tachycardia (AVRT), it quickly degenerated to ventricular tachycardia requiring electrical cardioversion. Ventricular pacing revealed the earliest atrial activation of the CS ostium. However, right and left PS endocardial RFA attempts failed to ablate the AP. CS venography revealed the presence of a mildly fusiform MCV (Figure B), and RFA in this area (Figure C and Video 1*) achieved successful ablation of ventriculoatrial conduction. Because of the close proximity of the CS ostium and posterolateral branch of the right coronary artery, caution should be exercised during RFA into the CS. A distinctive ECG clue for the presence of an epicardial AP in the PS area was a steeply negative delta wave in lead II. 223

Aberrant pathway in an anomaly : pre-excitation syndrome in association with coronary sinus aneurysm

Congenital coronary sinus anomalies are unusual and they rarely coexist with accessory atrio-ventricular pathways. These anomalies are generally symptomatic; however they can cause difficulty in mapping. The association between accessory pathway and coronary sinus anomalies may suggest an embryological link. Here, we report on a male patient with an accessory conducting pathway in the coronary sinus, leading to Wolff-Parkinson-White (WPW) syndrome.

Accessory pathway associated with an anomalous coronary sinus

Congenital coronary sinus anomalies are unusual and they rarely coexist with accessory atrioventricular pathways. These anomalies are generally asymptomatic, however they can cause difficulty in mapping. The association between accessory pathway and coronary sinus anomalies may suggest an embryologic link. In this case, we report a male patient with permanent form of reciprocating tachycardia coexistent with anomalous coronary sinus.

Left heart pacing--experience with several types of coronary vein leads.

Our experience with 121 coronary vein (CV) leads in 116 patients shows that CV leads are the leads of choice for pacing the left ventricle (LV). The information gained from pre-operative venous angiography permits individual selection of the most appropriate lead model for each case. The use of steerable electrophysiology catheters facilitates guide catheter cannulation of the coronary sinus (CS) when the anatomy is difficult and reduces the risk of complications. By selecting the CV lead model most suitable for each individual patient, we achieved successful implantation in 99.1% of patients. In this day and age, epicardial electrodes should be restricted to cases with CS anomalies which make CS cannulation impossible, and to LV lead implantation during heart surgery.

Prospective evaluation of the coronary sinus anatomy in patients undergoing electrophysiologic study.

Previous retrospective studies could find a predominant incidence of coronary sinus (CS) anomalies in patients with accessory pathways and a characteristic anatomy of the CS ostium in patients with atrioventricular nodal reentrant tachycardias (AVNRT). In the present prospective study, CS angiograms were prospectively performed to analyze the incidence of CS anomalies and to measure the diameters of the CS ostium. The study included patients referred for electrophysiologic study and catheter ablation of various tachyarrhythmias. The anatomy of the CS and its side branches was visualized [left anterior oblique (LAO) 30 degrees, right anterior oblique (RAO) 30 degrees] by retrograde angiography in 204 consecutive patients (82 women, 122 men, age 45 +/- 15 years); of these, 120 presented with 123 accessory pathways (45 left-sided, 33 right-sided, 45 septal). The diagnosis in the remaining patients was atrioventricular nodal reentrant tachycardia in 43 cases, atrial tachycardia or atrial fibrillation in 12, and ventricular tachycardia in 15. In 14 patients, the indication for the electrophysiologic study was an unexplained syncope. The CS angiogram was evaluated for anomalies and the size of the CS ostium was manually measured in both projections. Anomalies of the CS defined as diverticula, persistent left superior vena cava, or enlarged CS ostia were found in 18 patients (9%). Of those, CS diverticula were found in nine patients, all with a posteroseptal or left posterior manifest accessory pathway, which was abolished within the neck of the diverticulum in seven patients and at the posteroseptal tricuspid annulus in two patients. Persistence of the left superior vena cava was found in five patients, four had atrioventricular reentrant tachycardia secondary to five accessory pathways (left free wall in four, right midseptal in one), and one patient had atrioventricular nodal reentrant tachycardia (AVNRT). Enlargement of the CS ostium of > 25 mm width was detected in nine patients (5%), of whom four had AVNRT. However, the width of the CS ostium generally did not differ significantly between patients with AVNRT (LAO: 14.4 +/- 5.6; RAO 9.3 +/- 2.4 mm) compared with the control group (LAO 13.4 +/- 4.1; 8.2 +/- 1.9 mm). Anomalies of the CS as diverticula, persistent superior vena cava, or enlargement of the CS ostium are predominantly found in patients with accessory pathway-related tachycardias. Diverticula of the proximal CS were found in 7% of patients with accessory pathways; in these cases, ablation succeeded mostly by radiofrequency (RF) current delivery in the neck of the diverticulum. Enlargement of the CS ostium was more often seen in patients with AVNRT than in all other patients. However, in general the measurements of the coronary sinus ostium did not significantly differ in patients with AVNRT compared with the control group.

Direct angiography of the coronary sinus: impact on left posteroseptal accessory pathway ablation.

The purpose of this study was to determine the incidence and types of venous branches and anomalies in posteroseptal accessory pathways (APs) and whether these findings are indicative for successful ablation sites. Some posteroseptal APs may be located epicardially, or may be associated with venous anomalies or related to the middle cardiac vein. These APs account for many of the failures encountered during endocardial ablation. Direct coronary sinus (CS) angiography was performed in 43 consecutive patients with left posteroseptal APs (n = 23) and in 20 patients with AV nodal reentrant tachycardia prior to catheter ablation. In 14 (61%) of 23 APs, a venous branch or an anomaly of the CS was found in the posteroseptal region (6 with middle cardiac vein, 2 with other ventricular venous branches, and 6 had a diverticulum). Eleven (48%) of 23 APs were successfully abolished from within that demonstrated venous system, with a median of four radiofrequency impulses. In the remaining 12 (52%) patients, ablation was attempted from the endocardial site of the mitral annulus. Repeat angiography after energy delivery revealed no major complications in any patient. One (5%) patient with AV nodal reentrant tachycardia had evidence of a CS anomaly (P < 0.01). Various types of venous branches and anomalies are associated with the majority of patients with left posteroseptal APs. The APs are directly related to these complex findings, and AP conduction can easily be eliminated from within the venous branches. CS angiography is suggested prior to catheter ablation of left posteroseptal APs to facilitate the ablation procedure.

Efficacy and safely of radiofrequency catheter ablation of left-sided accessory pathways through the coronary sinus

Radiofrequency catheter ablation of left-sided accessory pathways (APs) with the use of an endocardial technique carries all potential risks of left heart catheterization. We analyzed the determinants of success, efficacy, and safety of radiofrequency catheter ablation from the coronary sinus (CS), as a potential alternative to the endocardial technique in these patients. Thirteen patients (mean age 40 ± 20 years) with 15 left-sided APs and a history of symptomatic supraventricular tachycardia were included in the study. Nine APs were localized in the left posteroseptal region, and the remaining 6 in the left free wall. Ablation from CS was attempted in 12 patients with 14 APs. In 1 patient ablation within the CS was not deemed safe because of a small venous lumen. All 14 APs were successfully ablated using either CS ablation alone or combined with the endocardial technique. Efficacy of the CS ablation as a primary technique was 56% (5 of 9 APs). In 5 additional APs, oblation in the CS eliminated pathway conduction after failed endocardial attempts. CS ablation either as a primary or a secondary technique eliminated conduction in 10 of 14 APs (71.4%) (group 1). In the remaining 4 APs (group 2), the primary CS attempt was unsuccessful and APs were ablated with a subsequent endocardial approach. Determinants of success for the CS method were local AP to atrial and/or ventricular electrogram amplitude ratios ≥ 1 (p < 0.05). The success rate of CS ablation was 83% in the left posteroseptal APs adjoining the branching point of the middle cardiac vein or a CS anomaly. Radiofrequency ablation in the CS was safe at the energy levels and durations used in this study, with no evidence of major or delayed vascular complications. During follow-up of 10 ± 7 months, there was no recurrence of sustained tachycardia in any patient who underwent successful ablation from the CS. We conclude that primary CS ablation can be an effective and safe alternative to the endocardial technique for ablation of leftsided APs with electrogram ratios ≥ 1. These findings are frequently seen in left posteroseptal APs in proximity to the middle cardiac vein or a CS anomaly.

1008-14 Radiofrequency Catheter Ablation of Left-sided Accessory Pathways: Selection of Coronary Sinus as the Primary Approach

We employed the coronary sinus (CS) for radiofrequency catheter ablation either as a primary technique or as a secondary approach after failed endocardial attempts in 12 pts (mean age 40 ± 20 yrs) with 14 accessory pathways (AP): 9 left paraseptal, 4 left posterolateral, 1 left anterolateral. AP to local atrial (AP/A) and ventricular (AP/V) electrogram amplitude ratios were calculated. CS angiograms were obtained in 9 pts. Results: AP potentials were recorded from the CS in all pts. All APs were successfully ablated using either CS ablation alone or combined with LV endocardial ablation. Catheter ablation within the CS eliminated conduction in 10 of 14 (71.4%) APs (Group 1) with the median of 7 (range 3 to 14) radiofrequency pulses and mean duration of 18 ± 5s at mean power of 22 ± 3W; 5 of these 10 APs were ablated from the CS as a primary method, and the other 5 APs were ablated from the CS after the failure of prior endocardial ablation. In remaining 4 APs (Group 2) the primary CS ablation failed and pathways were ablated with a subsequent endocardial approach. In Groups 1&amp;2, AP/A ratio was 1 ± 0.5 &amp; 0.55 ± 0.1 (p &lt; 0.05), and AP/V ratio was 1.2 ± 0.6 &amp;0.4 ± 0.3 (p &lt; 0.05), respectively. In Group 1,9/10 successful ablations had an AP/A andlor AP/V ratios ≥ 1, whereas in Group 2 none of the CS recordings had an electrogram ratio ≥ 1. In all 5 Group 1 pts failing endocardial ablation, an AP potential was not recorded at the, endocardial site. 5 of 7 successfully ablated left paraseptal APs were adjoining the middle cardiac vein or a CS anomaly. CS perforation or thrombosis was not observed. During followup of 10 ± 7 mos there was no recurrence of sustained supraventricular tachycardia in any pt. (1) The CS can be used for both mapping as well as safe and effective ablation of left-sided APs with radiofrequency power outputs upto 30 W. (2) It can be utilized as a primary ablation approach for APs with AP/A or AP/V ratios ≥ 1. (3) These findings are most commonly seen in left paraseptal APs in proximity to the middle cardiac vein or a venous anomaly. (4) Endocardial ablation can be reserved for left-sided APs with electrogram ratios &lt; 1.