Prospective study of retrograde coronary venography in patients with posteroseptal and left-sided accessory atrioventricular pathways

Giant diverticulum of coronary sinus with multiple accessory pathways treated with catheter ablation

Coronary sinus abnormalities are usually associated with arrhythmia disorders when symptomatic. We report a 5-year-old 14 kg patient with a giant diverticulum of coronary sinus and Wolff-Parkinson-White syndrome. Catheter ablation therapy was decided during follow-up due to inadequate response to multidrug therapy. Posteroseptal and left posterolateral accessory pathways were established and radiofrequency ablation was performed successfully through coronary sinus.

Optimization of free-breathing whole-heart 3-dimensional cardiac magnetic resonance imaging at 3 tesla to identify coronary vein anatomy and to compare with multidetector computed tomography

OBJECTIVE

This study optimizes use of 3-T magnetic resonance imaging (MRI) to delineate coronary venous anatomy and compares 3-T MRI with multidetector computed tomography (MDCT) measurements.

METHODS

The study population included 37 consecutive subjects (22 men, 19-71 years old). Whole-heart contrast-enhanced MRI images at 3 T were acquired using segmented k-space gradient echo with inversion recovery prepared technique. The MDCT images were obtained using nonionic iodinated contrast.

RESULTS

The coronary sinus and great cardiac, posterior interventricular, and anterior interventricular veins were visualized in 100% of cases by both MRI and MDCT. Detection of the posterior vein of the left ventricle and the left marginal vein by MRI was 97% and 81%, respectively. Bland-Altman plots showed agreement in ostial diameter measured by both modalities with correlation coefficients ranging from 0.5 to 0.76. Vein length and distances also agreed closely.

CONCLUSIONS

Free-breathing whole-heart 3-dimensional MRI at 3 T provides high-spatial-resolution images and could offer an alternative imaging technique instead of MDCT scans.

Coexistence of Left-Sided Atrioventricular Accessory Pathways With a Common Inferior Pulmonary Vein Ostium

Background—

As the technique for radiofrequency catheter ablation for atrial fibrillation (AF) has progressed, so has our knowledge of both normal and abnormal anatomy of the left atrium and pulmonary veins (PV). We treated several AF patients with accessory conduction pathways (ACP) who were also found to have a common ostium of inferior PVs (CIPV), a relatively rare PV anomaly. No relation between ACP and PV anomalies has ever been reported, and the aim of our study was to study this association.

Methods and Results—

This study included 137 consecutive patients (104 men; mean age, 60±9 years) who underwent AF ablation for paroxysmal and persistent AF at our institution from March 2009 to August 2010. We analyzed coexisting supraventricular tachycardias and left atrium and PV morphology by multidetector row CT. Thirty-eight of 137 patients (27.7%) were found to have some PV anomaly, consisting of 13 with a common trunk of left PV, 19 with right additional PV, 3 with a common trunk of right PV, and 3 with CIPV. Thirty-one patients (22.6%) had supraventricular tachycardias. They were 26 cases of atrial flutter, 4 of Wolff-Parkinson-White syndrome, and 3 of atrioventricular nodal reentrant tachycardia. The prevalence of a coexisting ACP was significantly higher in patients with CIPV than in those without CIPV (3 of 3 [100%] versus 1 in 134 [0.7%]; P <0.0001). All ACPs with CIPV were located in the left side. The other supraventricular tachycardias were not associated with any PV anomalies.

Conclusions—

There is a possible association between CIPV and left-sided ACP in AF patients. This suggests that there is a likelihood of developmental association between them.

Notch signaling regulates murine atrioventricular conduction and the formation of accessory pathways

Ventricular preexcitation, which characterizes Wolff-Parkinson-White syndrome, is caused by the presence of accessory pathways that can rapidly conduct electrical impulses from atria to ventricles, without the intrinsic delay characteristic of the atrioventricular (AV) node. Preexcitation is associated with an increased risk of tachyarrhythmia, palpitations, syncope, and sudden death. Although the pathology and electrophysiology of preexcitation syndromes are well characterized, the developmental mechanisms are poorly understood, and few animal models that faithfully recapitulate the human disorder have been described. Here we show that activation of Notch signaling in the developing myocardium of mice can produce fully penetrant accessory pathways and ventricular preexcitation. Conversely, inhibition of Notch signaling in the developing myocardium resulted in a hypoplastic AV node, with specific loss of slow-conducting cells expressing connexin-30.2 (Cx30.2) and a resulting loss of physiologic AV conduction delay. Taken together, our results suggest that Notch regulates the functional maturation of AV canal embryonic myocardium during the development of the specialized conduction system. Our results also show that ventricular preexcitation can arise from inappropriate patterning of the AV canal-derived myocardium.

Trans-Coronary-Venous Interventions

The coronary venous system is routinely targeted during electrophysiological measurements or cardiac resynchronization therapy. However, several novel interventional techniques require coronary venous catheterization and visualization as well as transvenous delivery of devices and/or therapeutic agents. Recent reports suggest the possibility of a transvenous approach for the interventional treatment of refractory angina and mitral valve regurgitation. In addition, the coronary venous system has been used as a route for the delivery of stem cells in patients with left ventricular dysfunction due to ischemic heart disease. We review the potential value of using a coronary venous approach in association with recent therapeutic developments in the interventional treatment of structural and ischemic heart disease. We will also discuss techniques related to coronary venous catheterization.

[A 66-year old female patient with tachycardia and syncope]

A 66-year old female patient suffered from paroxysmal tachycardias, palpitations, dizziness and once a short period of unconsciousness. The surface ECG showed preexcitation, and the clinical diagnosis of WPW syndrome was established. The electrophysiological study revealed the rare occurrence of an epicardial posteroseptal accessory pathway. Retrograde venous angiography of the coronary sinus showed a coronary sinus diverticulum. Ablation of the accessory pathway in the neck of the coronary sinus diverticulum was successful. Epicardial accessory pathways in a coronary sinus diverticulum are rare. However, successful ablation of accessory pathways at this site is safely possible.

Investigation of coronary venous anatomy by retrograde venography in patients with malignant ventricular tachycardia

BACKGROUND

The coronary venous system is increasingly used for left ventricular or biventricular pacing in patients with severe heart failure. The present study investigated the structure of the coronary veins in patients presenting with structural heart disease and malignant ventricular tachyarrhythmias. The availability of veins for possible lead placement was assessed.

METHODS AND RESULTS

The number, relative size, and location of coronary veins were evaluated by retrograde venography in 129 patients undergoing cardioverter-defibrillator implantation. Detailed x-ray image analysis was performed in 86 patients, for whom optimal coronary sinus occlusion and vein visualization was achieved. The anterior interventricular vein and the middle cardiac vein were visible in 85 (99%) of 86 patients and in 86 (100%) of 86 patients, respectively. Between these 2 veins, at least 1 additional prominent vein was visible in 85 (99%) of 86 patients. Just 1 vein was present in 44 (51%) of 86 patients. Two veins were observed in 40 (46%) of 86 patients, and >2 veins were visualized in 2 (2%) of 86 patients. Venous anatomy allowed positioning of a 0.014-in guidewire in a coronary vein in 115 (93%) of 124 patients.

CONCLUSIONS

The presence, diameter, angulation, and tortuosity of veins as visualized by retrograde venography determine their acceptability for the placement of a lead in a predetermined location. Despite the considerable variability of the coronary venous system among patients, a lateral vessel for lead introduction was available in 82%, and a posterior or lateral vessel was available in 99% of individuals within a patient population that could potentially benefit from a lead on the left ventricle.

Radiofrequency catheter ablation of posteroseptal accessory pathways--results of a step-by-step ablation approach

INTRODUCTION

Transcatheter radiofrequency ablation of posteroseptal accessory pathways (AP) is challenging. A number of different interventional approaches have been suggested by different groups. The selection of the initial approach is crucial in order to reduce radiation exposure and the number of unsuccessful lesions applied. We present our ablation technique as guided by a simplified electrocardiographic analysis of the delta wave polarity and the electrophysiologic mapping results.

METHODS AND RESULTS

Out of 35 manifest APs encountered in the right (n=17) or the left posteroseptum (n=18) in 35 patients, 34 were successfully ablated. Despite their left sided location, 7 of the 18 "left" sided APs were ablated after switching from an initial arterial to a venous approach looking for an appropriate target site in the right posteroseptal space or within the coronary sinus network. The other 11 left sided APs were ablated in the mitral ring, on 2 occasions, on their atrial aspect through a retrograde transmitral approach. On the contrary, 16 of the 17 "right" sided APs were successfully ablated exclusively through a venous approach. Fourteen of these were ablated in the right posteroseptum, in 2 cases, only after reaching their ventricular aspect. Two right sided APs were interrupted in the coronary sinus os and the middle cardiac vein respectively.

CONCLUSION

It appears that even though the electrocardiographic and electrophysiologic location of the AP in the posteroseptal space helps select the appropriate initial approach, it does not always guarantee a successful ablation procedure in the expected site of the corresponding atrioventricular ring. Not uncommonly, it will be necessary to look after intermediate target sites within the coronary sinus to improve the overall ablation success rate.

Congenital malformations of the right atrium and the coronary sinus: an analysis based on 103 cases reported in the literature and two additional cases

STUDY OBJECTIVES

Congenital malformations of the right atrium (RA) and the coronary sinus (CS) are rare, and only sporadic cases have been reported. Little is known about the clinical relevance of this disorder. We report on two patients, one with a giant RA diverticulum, the other with a diverticulum of the CS, and review 103 cases of such malformations that have been reported previously.

DESIGN

A MEDLINE search was performed to collect all cases of congenital malformations of the RA and the CS reported in the literature between 1955 and 1998. Cases were classified into the following categories: (1) congenital enlargement of the RA; (2) single diverticulum of the RA; (3) multiple diverticula of the RA; and (4) diverticulum of the CS. Clinical presentation and outcome of the different types of malformations were analyzed.

RESULTS

The patients most frequently presenting with symptoms were those with diverticula of the CS (n = 28) followed by those with single diverticula of the RA (n = 13), multiple diverticula (n = 4), and congenital enlargements of the RA (n = 60). The percentages of symptomatic patients were 93, 84, 75, and 53%, respectively. Symptoms were frequently caused by arrhythmias. Supraventricular tachycardia (SVT) was found in 42 of the patients (40%) and was most common in patients with diverticula of the CS (24 of 28 patients) and multiple atrial diverticula (3 of 4 patients). Sudden cardiac death was reported more frequently in patients with diverticula of the CS (18%) compared to those with congenital enlargement of the RA (5%) or single or multiple diverticula of the RA (6%). All seven patients with diverticula of the CS who were not treated with catheter or surgical ablation eventually died.

CONCLUSION

Congenital malformations of the RA and the CS frequently are associated with arrhythmias. SVT and sudden cardiac death have been reported in a significant percentage of patients with diverticula of the CS.

Characteristics and radiofrequency catheter ablation of septal accessory atrioventricular pathways

Septal accessory AV pathways are located in the complex AV septal space that also contains the specialized conduction system. They have unique electrocardiographical and electrophysiological characteristics to be differentiated from free-wall accessory pathways. Some of the septal pathways have AV nodelike conduction properties and produce a similar activation sequence in the retrograde conduction. Several methods have been developed to distinguish them from AV nodal pathways. Radiofrequency catheter ablation using the titration method and endocardial approach without entrance into the coronary sinus is effective in eliminating most of the septal accessory pathways without impairment of AV conduction. However, some posteroseptal accessory pathways may require energy application inside the coronary sinus, thus information of the coronary sinus anatomy is important for preventing complication.

Angiographic anatomy of the coronary sinus and its tributaries

Permanent left ventricular pacing has been shown to improve the hemodynamic and clinical status of patients with severe heart failure. To pace the left ventricle, the electrode is implanted in tributaries of the coronary sinus (CS). However, the anatomy of cardiac veins with this purpose in mind has not been described in detail.

METHODS

One hundred consecutive patients admitted for coronary angiography had a simultaneous coronary venography performed after the injection of 8 to 10 mL of contrast material into the left coronary artery. Cardiac veins were analyzed in antero-posterior, left anterior oblique 60 degrees, and right anterior oblique 30 degrees views by three different observers. The number, dimension, angulation, and position of the coronary sinus and of its tributaries were studied.

RESULTS

Two veins are consistently present: the middle cardiac vein (mean diameter 2.62 +/- 1.26 mm) and the great cardiac vein (mean diameter 3.55 +/- 1.24 mm). The left posterior vein(s) (LPV) (mean diameter 2.25 +/- 1.2 mm) is (are) variable in number (ranging from 0 to 3), size, and angulation. The absence of LPV limits the ability to pace the left ventricle endovenously. The diameter of the vein (< 2 mm) and its angulation may also complicate the insertion of the lead.

CONCLUSION

Angiographic analysis of dimensions, tortuosity, number, and angulation of venous tributaries of the CS seems to allow the insertion of commercially available pacing leads in approximately 85% of cases. An increase in this percentage hinges on the development of new, dedicated leads.

Catheter ablation of accessory pathways

Radiofrequency catheter ablation is a highly effective, curative treatment for arrhythmias related to accessory atrioventricular connections. Compared with medical therapy, ablation is more definitive, is more cost-effective, and is associated with a lower risk of proarrhythmia. This article updates the reader on the current indications, techniques, and innovations related to ablation of accessory pathways using radiofrequency energy.

[Catheter ablation and implantable atrial defibrillators in supraventricular cardiac arrhythmias]

Non-pharmacological tools for treatment of supraventricular tachycardias include radiofrequency catheter ablation, antiarrhythmic surgery, and electrical therapies. Radiofrequency catheter ablation is the first choice in the treatment of symptomatic patients with AV nodal reentrant tachycardias and atrioventricular reentrant tachycardias because of its high success rate and its low complication rate. Furthermore, transvenous radiofrequency catheter ablation may be considered as a curative approach in patients with atrial flutter and in patients with ectopic atrial tachycardias. Whereas the application of radiofrequency catheter ablation for the curative treatment of atrial fibrillation is still experimental, palliative therapy modalities such as AV nodal modification or AV nodal ablation may be performed in patients with drug refractory atrial fibrillation with rapid ventricular response. The recurrence rate of atrial fibrillation is in the range of 40 to 60% within a year despite antiarrhythmic drug treatment. Internal atrial fibrillation is a safe and effective method for acute termination of atrial fibrillation, especially after unsuccessful external cardioversion. The electrotherapy with the implantable atrial defibrillator should be considered as an alternative approach in patients with symptomatic, long lasting, and drug refractory episodes of atrial fibrillation. This innovative electrotherapeutic tool is currently under clinical evaluation. For the selection of the most appropriate therapy, the risk-benefit-ratio has to be taken into account in each individual patient.