Steven J. Fowler

Imaging of Patent Foramen Ovale with 64-Section Multidetector CT

PURPOSE To investigate the feasibility of 64-section multidetector computed tomography (CT) by using CT angiography (a) to demonstrate anatomic detail of the interatrial septum pertinent to the patent foramen ovale (PFO), and (b) to visually detect left-to-right PFO shunts and compare these findings in patients who also underwent transesophageal echocardiography (TEE). MATERIALS AND METHODS In this institutional review board-approved HIPAA-compliant study, electrocardiographically gated coronary CT angiograms in 264 patients (159 men, 105 women; mean age, 60 years) were reviewed for PFO morphologic features. The length and diameter of the opening of the PFO tunnel, presence of atrial septal aneurysm (ASA), and PFO shunts were evaluated. A left-to-right shunt was assigned a grade according to length of contrast agent jet (grade 1, <or=1 cm; grade 2, >1 cm to 2 cm; grade 3, >2 cm). In addition, 23 patients who underwent both modalities were compared (Student t test and linear regression analysis). A difference with P < .05 was significant. RESULTS A flap valve, seen in 101 (38.3%) patients, was patent at the entry into the right atrium (PFO) in 62 patients (61.4% of patients with flap valve, 23.5% of total patients). A left-to-right shunt was detected in 44 (16.7% of total) patients (grade 1, 61.4%; grade 2, 34.1%; grade 3, 4.5%). No shunt was seen in patients without a flap valve. Mean length of PFO tunnel was 7.1 mm in 44 patients with a shunt and 12.1 mm in 57 patients with a flap valve without a shunt (P < .0001). In patients with a tunnel length of 6 mm or shorter, 92.6% of the shunts were seen. ASA was seen in 11 (4.2%) patients; of these patients, a shunt was seen in seven (63.6%). In 23 patients who underwent CT angiography and TEE, both modalities showed a PFO shunt in seven. CONCLUSION Multidetector CT provides detailed anatomic information about size, morphologic features, and shunt grade of the PFO. Shorter tunnel length and septal aneurysms are frequently associated with left-to-right shunts in patients with PFO.

Trapping of vascular clip closure device in previously accessed femoral puncture site.

A 50-year-old male with peripheral vascular disease, coronary artery disease, and ischemic cardiomyopathy was evaluated for recurrent chest pain. From the emergency room, the patient was admitted to the chest pain unit and myocardial infarction was excluded. However, dobutamine echocardiography showed an inducible lateral wall motion abnormality at peak infusion. He was referred for diagnostic coronary angiography and potential percutaneous coronary intervention. Cardiac catheterization was performed using a 6Fr arterial sheath placed in the right common femoral artery and 6Fr Judkins left and right diagnostic coronary catheters. Angiography revealed moderate epicardial atherosclerosis in the circumflex and first obtuse marginal vessels, without significant flow limiting lesions. At the conclusion of the procedure, after confirming that the puncture site was at the level of the common femoral artery by iliofemoral angiography, arteriotomy closure was performed using a StarClose vascular closure system. The standard deployment steps were followed without incident: (1) exchanging the sheath, (2) inserting the clip applier and locking into the sheath, (3) deploying the foot stop (vessel locator) inside of the vessel, (4) retracting the device to the vessel stops, (5) splitting the sheath and advancing the clip delivery housing, (6) applying downward pressure and firing the clip release. After the last step, the operator could not remove the device despite considerable upward force. Repeat cineflouroscopy of the area with magnification revealed that the nitinol foot system that serves as the vessel (stopper), locator remained deployed, and the vascular clip had not fully passed through the adventia to the external femoral wall (Fig. 1). Hemostasis was achieved by proximal manual compression and the patient remained hemodynamically stable, pain-free, with intact distal pulses, and without evidence of local hematoma. An attempt to retract the foot system was made by disassembling the device, but to no effect. Following contact with the device manufacturer, no further forceful maneuvers were performed, and vascular surgery was consulted for local exploration and device removal with controlled vascular hemostasis if needed. Femoral exploration revealed that the device was trapped outside the arterial wall in an area of fibrous adventitia; no damage or bleeding was noted at the arteriotomy site (Fig. 2). Further dissection of the device ex vivo showed that the metal cuff mechanism responsible for the deployment of the vessel locator was embedded in scar tissue and that the vascular clip was 2 cm off of the arterial wall, also embedded in scar (Fig. 3). The patient tolerated the procedure well and his residual hospital course was uneventful.

Successful catheter ablation of focal ventricular fibrillation originating from the right ventricle

Sudden cardiac death from ventricular fibrillation (VF) typically occurs in patients with structural heart disease, but in 5 to 10 percent VF is “idiopathic,” occurring in normal hearts. Recently, there has been the description and growing recognition of patients with VF that has a focal origin, the common sites being in the right ventricular outflow tract (RVOT) and sites in the left ventricle. A focus within the right ventricle outside the RVOT is rare. We present a case of a woman with VF storm that was localized to the inferobasal right ventricle and was successfully treated with radiofrequency ablation.

Implantable Loop Recorder in Inherited Arrhythmia Diseases: A Critical Tool for Symptom Diagnosis and Advanced Risk Stratification

The differential diagnosis between benign syncope common in a young population and life-threatening arrhythmic ones represents a major challenge in the management of patients with inherited arrhythmias (IAs) [(1)][1]. In this population, ventricular arrhythmias can often be hemodynamically tolerated