Application of combined transthoracic echocardiography and contrast transthoracic echocardiography for percutaneous intervention of patent foramen ovale

AIM To evaluate the application value of transthoracic echocardiography (TTE) combined with contrast transthoracic echocardiography (cTTE) for percutaneous intervention of patent foramen ovale (PFO). METHODS Ninety PFO patients, who aged from 14 to 61 years (mean age, 40±15) and underwent percutaneous PFO closure, were assessed, monitored and followed up by TTE, cTTE and transoesopheageal echocardiography (TEE). RESULTS TTE or TEE showed that 52 patients had simple PFO (57.8%) and 38 patients had complicated PFO (42.2%). The right to left shunt (RLS) at rest was detected by the preoperative cTTE in 38 patients (42%), of whom were 24 cases (27%) with a small amount of RLS, 11 cases (12%) with moderate RLS and 3 cases (3%) with a large number of RLS. After Valsalva maneuver, 8 patients had moderate RLS and the rest patients had a large amount of RLS. The detectable rate of a large amount of RLS after Valsalva maneuver was significantly higher than that at rest (P<0.01). The 52 patients with simple type PFO were treated with PFO occluders, including 38(73%) 18/25 mm-occluders, 6(12%) 30/30 mm- occluders and 8(15%) 25/35 mm-occluders. Our data indicated the utilization ratio of 18/25 mm-occluder was significantly higher than that of 30/30 mm-occluder and 25/35 mm-occluder (P<0.01). Thirty-seven of the 38 complicated PFO patients were treated with single occluders, including 16(42%) 18/25 mm-PFO occluders, 17(45%) 25/35 mm- PFO occluders and 4 atrial septal defect (ASD)-occluders (11%). One complicated PFO patient coexisting with small ASD had 20 mm hole spacing and was treated with 18/18mm and 25/35 mm- PFO occluders. Complete closure rates (no RLS) by cTTE at the follow-up time of 3 months, 6 months and 1 year were respectively 40%, 67% and 74%. Residual RLF was found in 23 patients at 1 year after operation. The time of microbubbles appeared over 5 cardiac cycle in 22 of the 23(96%) patients. CONCLUSION The combination of TTE with cTTE is indispensable for preoperative screening, choice of occluder and treatment evaluation and is thus of important value for ensuring successful percutaneous intervention of PFO.