Transcatheter Coil Embolization of Multiple Bilateral Congenital Coronary Artery Fistulae

ABSTRACT: Coronary artery fistulae represent the most frequent congenital anomalies of the coronary arteries, but remain a relatively uncommon clinical problem. Moreover, multiple fistulae originating from both the left and the right coronary arteries and draining into the left ventricular chamber are a rare condition. Due to the low prevalence of these anomalies, the appropriate management of patients with symptomatic coronary artery fistulae is controversial. Transcatheter closure approaches have emerged as a less invasive strategy and are nowadays considered a valuable alternative to surgical correction with similar effectiveness, morbidity and mortality. The percutaneous management, however, is mainly limited by the individual anatomic features of the fistula and an appropriate patient’s selection is considered as a key determining factor to achieve complete occlusion. Thus, success rates of transcatheter closure techniques reported in the literature are extremely variable and highly dependent upon the nature of the follow up, which, at present, is not standardized. The optimal management of symptomatic patients with multiple coronary artery fistulae still remains a challenging problem and has been traditionally considered as an indication for cardiac surgery. We report here the case of a patient with double bilateral congenital coronary artery fistulae arising from both the left and right coronary arteries and draining individually into the left ventricular chamber. This patient underwent successful transcatheter anterograde closure of both fistulae using a microcoil embolization technique. J INVASIVE CARDIOL 2010;22:142–145 Coronary artery fistulae (CAF) represent a relatively uncommon clinical problem, with an estimated prevalence of Case Presentation. A 43-year-old male with no known history of coronary artery disease presented to the emergency department complaining of typical exertional chest pain during the preceding weeks. The patient was treated for a stage III HIV infection with antiretroviral therapy, and his cardiac risk factors included arterial hypertension and dyslipidemia. The electrocardiogram (ECG) demonstrated sinus bradycardia, flat T waves in the inferior leads and negative T waves in precordial leads V3–V6. Serial cardiac enzymes were within normal limits. Because of a highly symptomatic typical angina and a pathological ECG, the patient was scheduled for elective coronary angiography, which revealed the presence of two CAF, the first originating from the right coronary artery (RCA) and the second from the ramus intermedius (ramus) coronary artery, both draining into the left ventricle, without evidence of obstructive coronary artery disease. We postulated that the patient’s typical ischemic symptoms were caused by a coronary steal phenomenon secondary to the fistulae. Transcatheter closure of both CAF was recommended to relieve the patient’s clinical symptoms. Transcatheter Closure Technique. Transcatheter closure was attempted during two successive procedures, each by an anterograde approach via a 6 French (Fr) femoral access and using a microcoil embolization technique. The CAF originating from the ramus and draining into the left ventricle was closed at the time of the first diagnostic coronary angiogram. Angiographic views allowed adequate visualization of the fistula (Figure 1) in order to determine the appropriate site for device delivery and the coil size required. A 6 Fr Voda Left 3.5 Runway® guide catheter (Boston Scientific Corp., Natick, Massachusetts) was positioned at the left coronary ostium. The delivery catheter, a 2.7 Fr x 130 cm Progreat® microcatheter guide (Terumo Medical, Somerset, New Jersey), was advanced under fluoroscopic guidance over a Hi-Torque Whisper MS® hydrophilic guidewire (Guidant Corp., Indianapolis, Indiana) directly to the distal coronary artery in order to occlude the drainage orifice and minimize the risk of distal embolization. Hemodynamic parameters were assessed using the microcatheter at the level of the fistula; the pressure curve measurements revealed a typical ventricular pattern (Figure 2), confirming the direct connection between the coronary artery and the left ventricle through the fistula. The microcatheter was positioned in the proximal segment of the fistula (diameter of the vessel at this point: 0.75 mm) and a single stainless-steel MWCE® 18S–3/2 microcoil (Cook Medical, Inc., Bloomington, Indiana) was deployed. After delivery of the device, control angiography confirmed the successful occlusion, as no residual flow from the fistula was noted (Figure 1). No per procedural complications occurred and the patient was discharged the following day. Closure of the second CAF was performed 2 weeks later. Selective angiography confirmed the localization of the CAF originating from the distal RCA and draining into the left ventricular chamber (Figure 3). A 6 Fr Sherpa HSB II® guide catheter (Medtronic, Inc., Minneapolis, Minnesota) was positioned at the right coronary ostium and a 2.4 Fr x 150 cm Progreat® microcatheter guide was advanced over a Hi-Torque Whisper MS® hydrophilic guidewire to the distal RCA. A second MWCE® 18S-3/2 single microcoil was successfully delivered to the proximal segment of the fistula at the level of a relatively large diameter of the vessel (1.5 mm). After placement of the device, complete occlusion of the fistula was confirmed by control angiography (Figure 3), and no complication occurred during the procedure. The patient subsequently reported complete disappearance of the clinical symptoms. No ECG changes suggesting myocardial ischemia were noted following the two procedures. At 6-month follow up, the patient remained free from cardiovascular symptoms and the echocardiogram showed preserved left ventricular systolic function without segmental wall motion abnormalities or residual shunt. A cardiac magnetic resonance imaging (MRI) scan confirmed the absence of stress-induced myocardial ischemia, suggesting the complete closure of both fistulae; moreover, myocardial damage, either prior or secondary to the transcatheter closure procedure, was excluded by the absence of myocardial late enhancement after gadolinium injection.

Discussion

CAF are the most frequent congenital anomalies of the coronary arteries, but remain a relatively uncommon clinical problem. We described here the unique case of a patient with multiple bilateral symptomatic congenital CAF draining into the left ventricle who underwent successful transcatheter anterograde closure of both fistulae using a microcoil embolization technique. Congenital CAF are usually solitary anomalies and multiple fistulae remain infrequent, accounting for only 8% of cases.12 Moreover, congenital CAF generally arise from and drain into the right coronary artery system, while fistulae draining into the left ventricle or multiple fistulae originating from both the left and right coronary arteries, as reported here, are even more uncommon.3,12–14 Interestingly, and for the first time to our knowledge, we demonstrated invasive proof of a direct vascular connection between the coronary artery lumen and the cardiac ventricular chamber through the CAF by hemodynamic measurements revealing a typical ventricular pattern of the pressure curve at the level of the fistula. Due to the infrequency of these anomalies, the appropriate management of symptomatic patients is controversial. Transcatheter closure approaches have emerged as a less invasive strategy to surgical correction, since the safety and effectiveness of percutaneous closure techniques have been demonstrated in both pediatric and adult populations.6,10,15 Microcoil embolization, using either an anterograde or retrograde approach, is considered, nowadays, the predominant method for transcatheter closure;10 recent developments in catheter and coil technologies have made it a safe procedure, and various occlusion devices and techniques for device delivery are currently available.7,13 Selection of the appropriate transcatheter occlusion technique and closure device is mainly based on the individual anatomic features of the CAF, thus, assessment of the optimal site for device delivery and estimation of the shunt size are considered as key determining factors to achieve complete occlusion. The optimal treatment of patients with multiple CAF still remains a challenge. Recently, transcatheter closure techniques have also been suggested as an effective alternative to cardiac surgery in selected patients,16,17 particularly when a single drainage site is documented.18 However, limited data are available regarding the long-term results of patients undergoing percutaneous management of multiple CAF. A detailed evaluation of the origin and drainage sites of the fistulae is essential before selecting the appropriate closure technique. We demonstrated here that a transcatheter anterograde closure approach using a microcoil embolization technique for multiple and bilateral CAF is feasible and relatively safe and effective. Transcatheter approaches, however, are limited by the accessibility to the distal coronary artery and percutaneous management may be difficult or impossible in ~15% of the patients10 due to the inability to deliver the catheter to the distal part of the fistula. The main technical limitations consist of extreme vessel tortuosity, small diameter of the coronary artery and presence of multiple drainage sites or coronary branches at the site of optimal device position. These findings emphasize the need for appropriate patient selection before considering percutaneous closure management of symptomatic fistulae. Interestingly, compared to previous reports, we demonstrated that CAF can also be successfully coiled at the level of a relatively large vessel diameter (0.75 and 1.5 mm, respectively), and not at the usual narrowest point of the fistula, without producing consecutive myocardial damage as confirmed by cardiac MRI. This approach may be of interest in selected patients when delivery of the catheter to the distal portion of the fistula is technically limited. Current management of symptomatic patients is mainly based on retrospective observational studies, but reports in the literature are limited by small patient samples and short-term follow-up periods. Furthermore, success rates of percutaneous closure procedures are extremely variable and greatly depend upon the nature of the follow up. In some studies, follow up was limited to a clinical evaluation looking for persistent or recurrent symptoms, while others included a more detailed assessment with control echocardiography or coronary angiography, consequently reducing the success rates of these procedures. Residual or recurrent shunts after transcatheter closure have been reported in 10–20% of patients10,19 and may require further procedures to achieve complete occlusion. In one study10 including 33 patients who underwent successful transcatheter closure, a coil embolization technique was used in the majority of the cases. Immediate post-procedural coronary angiography documented complete occlusion in ~60% of these patients, while the remaining showed a small residual flow. Although one-third of patients experienced procedural complications mainly related to transient ECG changes and benign arrhythmias, severe complications occurred in only 2 patients. Over a mean follow-up period of 3 years, all patients remained asymptomatic and echocardiography confirmed complete occlusion in ~80%. In another study15 including 14 adult patients who were treated with a transcatheter retrograde coil embolization approach, complete closure was achieved in only half of patients, while persistence of trivial shunts was noted in one-third of patients and required additional procedures for complete occlusion. No periprocedural deaths occurred, but complications included a 14% rate of both fistula dissection and device embolization. During a follow-up period of 2.5 years, a relatively high proportion of patients (~80%) with successful closure remained symptom-free. Limited data regarding the optimal follow up of patients after a successful transcatheter closure of CAF are currently available in the literature. Therefore, the absence of a standardized, detailed follow-up protocol may prevent one from drawing any conclusions concerning long-term results and outcome predictors after percutaneous management, particularly in patients with multiple or bilateral CAF.

Conclusion

Transcatheter anterograde closure of symptomatic CAF using a microcoil embolization technique, even in selected cases of multiple and bilateral fistulae, appears to be a relatively safe and effective alternative to surgical correction. Success rates of transcatheter management are extremely variable in the literature and greatly depend upon the individual anatomic features of the fistula, emphasizing the need for appropriate patient selection to achieve complete occlusion. A detailed evaluation of the origin and drainage sites of the fistulae seems essential before selecting the appropriate closure technique in patients with multiple CAF. However, the absence of a standardized detailed follow up protocol may prevent clinicians from drawing any conclusions concerning long-term outcome of patients undergoing transcatheter closure of CAF. Prospective randomized clinical trials are currently limited by the relatively low prevalence of these anomalies, thus multicenter registries are needed to identify the outcome predictors and long-term results of transcatheter closure management.

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From the Service of Cardiology, Lausanne University Hospital, Lausanne, Switzerland. The authors report no conflicts of interest regarding the content herein. Manuscript submitted October 13, 2009 and accepted November 10, 2009. Address for correspondence: Dr. Juan Fernando Iglesias, Service of Cardiology, Centre Hospitalier Universitaire Vaudois (CHUV), Rue du Bugnon 46, 1011 Lausanne, Switzerland. E-mail: Juan-Fernando.Iglesias@chuv.ch

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References

1. Gillebert C, Van Hoof R, Van de Werf F, et al. Coronary artery fistulas in an adult population. Eur Heart J 1986;7:437–443. 2. Yamanaca O, Hoobbs RE. Coronary artery anomalies in 126,595 patients undergoing coronary arteriography. Cathet Cardiovasc Diagn 1990;21:28–40. 3. Kardos A, Babai L, Rudas L, et al. Epidemiology of congenital coronary artery anomalies: A coronary arteriography study on a central European population. Cathet Cardiovasc Diagn 1997;42:276–277. 4. Cebi N, Schulze-Waltrup N, Frömke J, et al. Congenital coronary artery fistulas in adults: Concomitant pathologies and treatment. Int J Cardiovasc Imaging 2008;24:349–355. 5. Gowda RM, Vasavada BC, Khan IA. Coronary artery fistulas: clinical and therapeutic considerations. Int J Cardiol 2006;107:7–10. 6. Balanescu S, Sangiorgi G, Castelvecchio S, et al. Coronary artery fistulas: Clinical consequences and methods of closure. A literature review. Ital Heart J 2001;2:669–676. 7. Schleich JM, Rey C, Gewillig M, et al. Spontaneous closure of congenital coronary artery fistulas. Heart 2001;85:E6. 8. Nakatani S, Nanto S, Masuyama T, et al. Spontaneous near disappearance of bilateral coronary artery–pulmonary artery fistulae. Chest 1991;99:1288–1289. 9. Kamiya H, Yasuda T, Nagamine H, et al. Surgical treatment of congenital coronary artery fistulas: 27 years’ experience and a review of the literature. J Card Surg 2002;17:173–177. 10. Armsby LR, Keane JF, Sherwood MC, et al. Management of coronary artery fistulae. Patient selection and results of transcatheter closure. J Am Coll Cardiol 2002;39:1026–1032. 11. Mavroudis C, Backer CL, Rocchini AP, et al. Coronary artery fistulas in infants and children: A surgical review and discussion of coil embolization. Ann Thorac Surg 1997;63:1235–1242. 12. Holzer R, Johnson R, Ciotti G, et al. Review of an institutional experience of coronary arterial fistulas in childhood set in context of review of the literature. Cardiol Young 2004;14:380–385. 13. Luo L, Kebede S, Wu S, Stouffer GA. Coronary artery fistulae. Am J Med Sci 2006;332:79–84. 14. Abdelmoneim SS, Mookadam F, Moustafa S, et al. Coronary artery fistula: Single-center experience spanning 17 years. J Interv Cardiol 2007;20:265–274. 15. Collins N, Mehta R, Benson L, et al. Percutaneous coronary artery fistula closure in adults: Technical and procedural aspects. Catheter Cardiovasc Interv 2007;69:872–880. 16. Vitek J, Moses JW, Roubin GS, et al. Transcatheter therapeutic embolization of multiple coronary artery fistulas. Circulation 2001;104:E19. 17. Li RG, Fang WY, Shi HY, et al. Transcatheter coil embolization of multiple coronary artery-to-left ventricle fistulas: Report of a rare case. Chin Med J (Engl) 2008;121:1342–1344. 18. Brown MA, Balzer D, Lasala J. Multiple coronary artery fistulae treated with a single Amplatzer vascular plug: Check the back door when the front is locked. Catheter Cardiovasc Interv 2009;73:390–394. 19. Kung GC, Moore P, McElhinney DB, Teitel DF. Retrograde transcatheter coil embolization of congenital coronary artery fistulas in infants and young children. Pediatr Cardiol 2003;24:448–453.