Percutaneous closure of patent foramen ovale and atrial septal defect: procedure outcome and medium-term follow-up

Percutaneous closure of atrial septal defect (ASD) and patent foramen ovale (PFO) has become increasingly utilized. The indications and results of percutaneous closure are diverse. AIM: To assess the indications, results, and complications of percutaneous closure of ASD and PFO in our tertiary center. METHOD: Case note review and retrospective analysis of all consecutive patients undergoing percutaneous closure over a 3-year period from January 2003 to October 2005 with a mean follow-up of 19 months (4-36). Results: There were 185 consecutive patients. The mean age was 44.9 years (SD 12.9) and 53% (n = 98) were males. There was 59% (n = 109) PFO and 41% (n = 76) ASD. The predominant indication for PFO closure was cerebrovascular accident (CVA) (42.2%, n = 46)- and for ASD, dilated right ventricle (68.4%, n = 52). Of all procedures, 94.6% (n = 175) were first time and 5.4% (n = 10) were redo for residual shunt. Overall, the success rate was 96.8% (n = 179) with two patients referred for surgical closure due to the large size of ASD and unsuitability for percutaneous closure, two procedures abandoned due to pericardial effusion, and two abandoned because the PFO was too small to cross. The Amplatzer device was used in 92.7% (n = 166) and the Starflex in 7.3% (n = 13). Minor complications were recorded in 10 patients (5.4%), of which 4 (2.2%) had minor venous access bleeding, 1 patient (0.5%) had retroperitoneal hematoma, and 2 patients (1.1%) had transient atrial fibrillation. One patient (0.5%) had transient inferior ST elevation during the procedure, one patient (0.5%) reported chest pain postprocedure, and one patient (0.5%) developed septicemia 3 weeks postprocedure. Major complications were recorded in three patients (1.5%), one patient (0.5%) with retroperitoneal hematoma requiring blood transfusion and two patients (1%) with pericardial effusion following transseptal puncture, requiring aspiration. No death, stroke, or device embolization was recorded. CONCLUSION: Our experience with percutaneous closure in adults demonstrates excellent results and safety with few complications. Percutaneous device closure will replace surgical closure for many ASDs and PFOs.     

Blood oxygen level-dependent (BOLD) MRI: A novel technique for the assessment of myocardial ischemia as identified by nuclear imaging SPECT

BACKGROUND: The different levels of deoxyhemoglobin in the ischemic myocardium, induced by stressors such as dipyridamole, can be detected by blood oxygen level-dependent (BOLD) MRI and may be used to diagnose myocardial ischemia. The aim of this study was to assess the signal change in the myocardium on BOLD MRI as well as wall thickening between rest and dipyridamole stress images in ischemic and non-ischemic myocardium as identified on SPECT imaging. METHODS: Twelve patients with stress-induced myocardial ischemia on SPECT underwent rest and dipyridamole stress MRI using a double breath-hold, T2()-weighted, ECG-gated sequence to produce BOLD contrast images as well as cine-MRI for wall thickening assessment in 10 of the 12 patients. Signal change on BOLD MRI and wall thickening were compared between rest and stress images in ischemic and non-ischemic myocardial segments as identified on SPECT. In each patient, two MRI slices containing 16 segments per slice were analysed. RESULTS: In total, there were 384 segments for BOLD analysis and 320 for wall thickening. For BOLD signal 137 segments correlated to segments with reversible ischemia on SPECT and 247 to normal segments, while for wall thickening 112 segments correlated to segments with reversible ischemia and 208 to normal segments. The average BOLD MRI signal intensity change was -13.8 (+/-16.3)% in the ischemic segments compared to -10.3 (+/-14.7)% in the non-ischemic segments (p=0.05). The average wall thickening was 6.4 (+/-3.4) mm in the ischemic segments compared to 8.7 (+/-3.8) mm in the non-ischemic segments (p<0.0001). CONCLUSION: Stress-induced ischemic myocardium has a different signal change and wall thickening than non-ischemic myocardium and may be differentiated on BOLD MRI. Larger studies are needed to define a threshold for detection and to determine the sensitivity and specificity of this technique.     

RASER angioplasty

The experience with a new approach of using combined debulking technique for treating heavily calcified coronary artery lesions with both LASER and high speed rotational atherectomy, which is being labeled as RASER PCI, is described. The RASER PCI approach has been used in three different patients with severely calcified, undilatable coronary artery lesions that were unresponsive to either technique alone, with successful and satisfactory outcome.     

A novel approach for under-expanded stent: excimer laser in contrast medium

The novel approach of using excimer laser in a contrast medium for treating an under-expanded stent in a calcified coronary artery is described. In this first reported case, the laser in a contrast medium was used to treat an under-expanded stent deployed 18 months prior in a calcified non-dilatable coronary artery lesion. The normal laser approach in saline medium flush during lasing to clear any contrast was not effective. The use of concurrent contrast during lasing was effective and successful to help expand the stent with a successful outcome.