Transcatheter closure of a huge pulmonary arteriovenous fistula with embolization coils

Pulmonary Arteriovenous Fistula with Pulmonary Hypertension - To Close or Not to Close?

A 37-year-old female presented to our facility suffering from exertional dyspnea for 2-3 months. Her chest x-ray showed a nodular shadow in the right lower lung, and chest CT revealed a pulmonary arteriovenous fistula (PAVF). Subsequent echocardiographic examination detected no intra-cardiac shunt but did indicate pulmonary hypertension as evidenced by a tricuspid regurgitation flow velocity of 4.17 M/sec. Contrast echocardiography with antecubital vein injection of agitated normal saline demonstrated visualization of the left heart chambers compatible with PAVF. At cardiac catheterization, pulmonary arterial pressure was 59/26 mmHg, mean 34 mmHg. Because there was no intra-cardiac communication detected, primary pulmonary hypertension was tentatively diagnosed. Pulmonary angiography demonstrated a PAVF arising from the lower right pulmonary artery, forming a secular structure on its course in draining into the left atrium through a long pulmonary vein. In this particular anomaly, a concurrence of PAVF with pulmonary hypertension, we judged that the PAVF might serve as a safety valve for pulmonary hypertension and should not be closed. We therefore left the PAVF untreated and thereafter provided medical management for this patient. The concomitant presence of PAVF and pulmonary hypertension is a rare clinical condition. The ultimate treatment strategy for this uncommon condition should be carefully considered.

KEY WORDS

Computed tomography; Contrast echocardiography; Pulmonary angiography; Pulmonary arteriovenous fistula; Pulmonary hypertension.

Usefulness of dynamic volume scanning with 320-row CT in detecting recanalization of pulmonary arteriovenous fistula after coil embolization

Pulmonary arteriovenous fistula is a congenital and rarely acquired anomalous direct communications between pulmonary arteries and veins. Transcatheter embolization using metallic coil or detachable balloon is one of the common treatment procedure. However, recanalization after the embolization is one of the concern and its differentiation from the retrograde filling via pulmonary vein is difficult except using invasive angiography. We report a case with recanalized pulmonary arteriovenous fistula non-invasively detected by dynamic CT angiography with 320-rows multi detector CT.

A 45-year-old women who had underwent coil embolization for pulmonary arteriovenous fistula was examined with dynamic CT angiography and antegrade contrast enhancement of the fistula was noted. The recanalization through the embolized artery was confirmed by digital subtraction angiography, and the second coil embolization was performed. The follow-up dynamic CT angiography at three months after the second procedure found the retrograde enhancement of aneurysmal sac and no antegrade shunt. The dynamic CT angiography was useful for the detect the recanalization of pulmonary arteriovenous fistula.

Delayed pulmonary artery recanalization was reported to be observed in 5- 10% of cases as a complication after the successful occlusion of segmental pulmonary artery. Lack of change in aneurysmal diameter of pulmonary arteriovenous fistula demonstrated by CT was reported as the result of persistent aneurysmal perfusion or aneurysmal thrombosis. However, the retrograde filling of aneurysmal sac via pulmonary vein or remnant collateral pathway to the pulmonary arteriovenous fistula were also considered. Therefore, before the invasive procedure, we performed dynamic CT angiography to detect the flow direction and pathway to the pulmonary arteriovenous fistula. Using dynamic CT angiography, we could obtain hemodynamic information through the aneurysmal sac of pulmonary arteriovenous fistula and decide to proceed to the invasive embolotherapy. Prospective perfusion CT scan could be an alternative to invasive angiography in the initial follow-up after the embolotherapy or in the cases with the recanalization of pulmonary arteriovenous fistula.

Transseptal guidewire stabilization for device closure of a large pulmonary arteriovenous malformation

A 46-year-old man presenting with massive hemoptysis was found to have a large pulmonary arteriovenous malformation (PAVM) in the right lung. Closure of the PAVM with an Amplatzer-type duct occluder was hampered by inability to advance the device delivery sheath into the PAVM due to vessel tortuosity and inadequate guidewire support. Atrial septal puncture was performed and a femorofemoral arteriovenous guidewire loop through the right pulmonary artery, PAVM, and left atrium was created. Traction on both ends of the guidewire loop allowed advancement of the device delivery sheath into the PAVM and successful completion of the procedure. Transseptal guidewire stabilization can be a valuable option during device closure of large PAVMs when advancement, stability, or kinking of the device delivery sheath is an issue.

Transcatheter closure of pulmonary arteriovenous malformations with amplatzer devices

OBJECTIVE

To review the authors' experience with transcatheter closure of pulmonary arteriovenous malformations (PAVMs) using amplatzer duct occluder (ADO) devices and vascular plugs (AGA Medical, Golden Valley, MN) and present a novel technique for delivery sheath placement and device delivery.

BACKGROUND

PAVMs can cause cyanosis, fatigue, polycythemia, and thromboembolic phenomena. Transcatheter closure using coils, detachable balloons, and various devices has replaced surgery as the preferred therapy.

METHODS

Between January 2001 and December 2004, five patients (2M, 3F) of median age 33 years (14-49) were referred for transcatheter closure of multiple PAVMs. All patients were diagnosed previously with hereditary hemorrhagic telangectasia. The procedures were performed with sedation using a percutaneous transcatheter technique via the femoral vein under fluoroscopic guidance.

RESULTS

A total of 14 PAVMs (11 ADO and 3 plugs) were closed in five patients. Three patients required two procedures after developing additional PAVMs. All attempts at PAVM closure were successful. Oxygen saturation increased from 88.4 +/- 6.1 to 96.4 +/- 0.5 (P < 0.05). No complications, including air or thromboembolism, hemoptysis, or chest pain, occurred. At median follow-up of 3.4 years (1.4-3.6), all patients are alive and have suffered no embolic phenomena or infection.

CONCLUSION

Amplatzer patent ductus arteriosus occluders and vascular plugs are safe and effective in the closure of PAVMs in the acute setting and at intermediate follow-up. Placement of a long delivery sheath can be facilitated by the methods outlined. Though promising, further clinical evaluation of these devices is required. Their apparent advantages must be compared to other techniques and devices for transcatheter PAVM closure.