A prospective multicenter registry of 0.010-inch guidewire and compatible system for chronic total occlusion: the PIKACHU registry.

OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of a 0.010-inch guidewire and a balloon catheter for treatment of chronic total occlusion (CTO). BACKGROUND: Pathological studies have shown that 60-70% of CTO lesions have microchannels of sizes equal to or less than 0.010 inch. METHODS: The PIKACHU registry is a prospective, multicenter registry study. A 0.010-inch guidewire had to be used as the first guidewire to attempt to pass the CTO lesion. The primary endpoint was device success using a 0.010 system. RESULTS: A total of 141 patients with 141 lesions were enrolled. The median duration of occlusion was 9 months (range 3-156). Average guiding catheter size was 5.8 +/- 0.7 Fr. and TRI was 76.6 %. CTOs were mostly between 10-20 mm long, observed in 53 occlusions. There were 107 lesions (75.9%) with bending of more than 45 degrees. Calcification was seen in 91 lesions (64.5%). A 0.010-inch guidewire was successfully passed through in 97 of 141 lesions (68.8%). A 0.010-inch guidewire compatible balloon catheter was passed in 87 of the 97 lesions (88.7%) and final PCI success was achieved in all the cases. The overall clinical success rate was 87.9% (124/141). No MACE or bleeding complications were observed. CONCLUSION: The PIKACHU registry data suggest that the 0.010-inch system is safe and practicable for treatment of CTO lesions.

Radiofrequency catheter ablation of premature ventricular complexes from right ventricular outflow tract improves left ventricular dilation and clinical status in patients without structural heart disease.

OBJECTIVES: The present study evaluated clinical benefits of radiofrequency catheter ablation (RFA) for premature ventricular complexes from right ventricular outflow tract (RVOT-PVC) in patients without structural heart disease. BACKGROUND: It is unknown whether PVC causes left ventricular (LV) dilation, which is a well-recognized precursor of LV dysfunction and heart failure, and whether eliminating PVC by RFA produces clinical benefits in patients with RVOT-PVC. METHODS: Frequency of PVC per total heart beats by 24-h Holter monitoring, left ventricular ejection fraction (LVEF), left ventricular end-diastolic internal dimension (LVDd), mitral regurgitation (MR) by echocardiogram, cardiothoracic ratio (CTR) by chest radiogram, and New York Heart Association (NYHA) functional class of 40 patients with RVOT-PVC without structural heart disease were evaluated before and 6 to 12 months after RFA. RESULTS: Before RFA, a subgroup of patients with frequent (>20%) PVC demonstrated significantly enlarged LVDd and CTR, reduced LVEF, increased MR, and deteriorated NYHA functional class as compared to the subgroup with rare (<20%) PVC (54 +/- 1 mm vs. 45 +/- 1 mm, 52 +/- 2% vs. 46 +/- 1%, 66 +/- 2% vs. 73 +/- 2%, 1.2 +/- 0.2 degree vs. 0.4 +/- 0.1 degree, and 1.8 +/- 0.2 vs. 1.3 +/- 0.1, respectively; p < 0.05). Furthermore, ablating RVOT-PVC readily produced the improvement of all these abnormalities (47 +/- 1 mm, 41 +/- 1%, 72 +/- 2%, 0.3 +/- 0.1 degree, and 1.0 +/- 0.0, respectively; p < 0.05 compared with before RFA). CONCLUSIONS: These findings suggest that frequent (>20%) RVOT-PVC may be a possible cause of LV dysfunction and/or heart failure, and RFA produces clinical benefits in these patients.