The utility of combining continuous wavelet transform analysis and high-density voltage map in predicting the long-term outcomes after ablation of persistent atrial fibrillation.

BACKGROUND: Continuous wavelet transform (CWT) analysis is a frequency analysis to detect areas of stable high-frequent activity (stable pseudo frequency [sPF]) during atrial fibrillation (AF). As previously reported, patients with the highest sPF area in pulmonary veins (PV) showed better short-term outcomes after PV isolation (PVI). This study sought to evaluate the efficacy of CWT analysis in predicting the long-term (2 years) outcomes after PVI. We also combined the left atrial (LA) voltage map with CWT analysis to further predict the outcome. METHODS: Persistent AF patients (n = 109, age 65 ± 10) underwent a CWT analysis at PVs and 8 LA sites during AF for pre-PVI analysis. After PVI during AF, CWT analysis was performed again in the LA as post-PVI analysis and was compared with pre-PVI analysis. A sinus voltage map of LA was created after cardioversion. RESULTS: Seventy patients had the highest sPF within PVs (PV-dominant group), while 39 patients had the highest sPF outside PVs (LA-dominant group). The global frequency in the LA showed a significant decrease after PVI only in PV-dominant group (6.55 ± 0.27 to 6.43 ± 0.37, P < 0.01). AF-free survival was better in PV-dominant group than LA-dominant group at 2-year follow-up (87.1% vs. 64.3%, P < 0.002). This trend was recognized throughout all degrees of low voltage area in the LA (LA-LVA), and AF-free survival was well predicted by combining CWT analysis and LA-LVA. CONCLUSIONS: By combining CWT analysis and sinus LA-LVA, the long-term AF-free survival after PVI was well stratified and predicted.

Features Suggesting Preferential Conduction in Pulmonary Artery Ventricular Arrhythmia for Identification of Successful Ablation Sites.

Radiofrequency catheter ablation (RFCA) for pulmonary artery ventricular arrhythmia (PAVA) can be difficult because of the occasional existence of PAVA with preferential conduction.This study described the characteristics of PAVA that demonstrate preferential conduction.We analyzed electrocardiographic and electrophysiological data from 8 patients found to have PAVAs with preferential conduction out of 183 patients (4.4%) with right ventricular outflow tract (RVOT) arrhythmias who underwent RFCA at our hospitals. The PAVA with preferential conduction were classified into two types. In type 1 PAVA, successful ablation sites (success-sites) exhibited discrete prepotentials with an isoelectric line, in which the activation time (AT) was ≥ 50 milliseconds. In type 2 PAVA, excellent pace mapping was achieved at two sites separated by ≥ 20 mm: one in the RVOT free wall and the other at the success-site in the pulmonary artery. Type 1 and 2 PAVA features were considered signs of a short and long preferential conduction pathway, respectively.There were four patients each with type 1 and 2 PAVA. Type 1 PAVA was distinguished by the isoelectric line at success-sites with the mean AT of 78 ± 25.1 milliseconds. In type 2 PAVAs, although the AT at RVOT sites was very short (18.5 ± 10.1 milliseconds), the AT at success-sites was longer than that at the RVOT by 42.3 ± 36.2 milliseconds. Type 2 PAVAs displayed distinct electrocardiogram (ECG) features (R wave in lead I, RR' in inferior leads, and transitional zone in V4) not found in typical PAVA ECGs.PAVA with preferential conduction can manifest in distinct ways on the ECG and intracardiac mapping. Knowledge of these features may facilitate successful RFCA of such PAVA cases.

Clinical Significance and Prognosis of Right Heart Thrombi Associated With Acute Pulmonary Thromboembolism　- Results of a Multicenter Registry of Thrombolysis in Japan.

BACKGROUND: Thrombolytic therapy is standard treatment in acute pulmonary thromboembolism (PTE) with hemodynamic instability. Although right heart thrombi (RHT) appear to increase mortality in acute PTE, large-scale studies of acute PTE with RHT are scarce.Methods and Results:Patient data (from August 2005 to May 2014) obtained from post-marketing surveillance of thrombolytic therapy using a tissue-type plasminogen activator were analyzed retrospectively. Of the 2,698 confirmed cases of acute PTE who underwent echocardiographic assessment, 166 (6.2%) were diagnosed with RHT. PTE patients with RHT, compared with those without RHT, had higher rates of mortality (20.2% vs. 10.4%, P<0.001), hemodynamic instability (53.0% vs. 37.7%, P<0.001), and PTE recurrence (6.6% vs. 2.3%, P=0.003). When considering PTE-related hemodynamic severity (cardiopulmonary arrest/collapse, massive, submassive, and non-massive), mortality was significantly higher in patients with RHT in the massive (19.8% vs. 7.7%, P=0.002) and submassive (8.0% vs. 2.8%, P=0.018) groups, whereas no significant differences was found between those with and without RHT in the cardiopulmonary arrest/collapse (51.7% vs. 52.1%, P=0.960) and non-massive (1.6% vs. 0%, P=0.596) groups. CONCLUSIONS: PTE patients with RHT had higher mortality, severity, and PTE recurrence rates. RHT was particularly associated with worse outcomes in patients with massive or submassive PTE.

Perforation of the hypopharynx after transesophageal echocardiography.

A 65-year-old obese woman with an oversized neck and dysphagia underwent transesophageal echocardiography (TEE). The procedure was complicated by difficulty in insertion from the pharynx to esophagus, and her head and neck gradually swelled. Computed tomography (CT) revealed extensive emphysema from the neck to superior mediastinum, which suggested pharyngeal perforation. A nasogastric tube was inserted, and the patient received antibiotics to prevent secondary mediastinitis. CT performed 1 week later showed improvement of emphysema and no evidence of mediastinitis. Perforation along the orogastric pathway during TEE is a rare but life-threatening complication to which physicians performing TEE should pay attention.

Evaluating microvascular obstruction after acute myocardial infarction using cardiac magnetic resonance imaging and 201-thallium and 99m-technetium pyrophosphate scintigraphy.

BACKGROUND: Few studies have compared the ability of cardiac magnetic resonance (CMR) with that of scintigraphy using 201-thallium (201-Tl) and 99m-technetium pyrophosphate (99m-Tc PYP) to evaluate microvascular obstructions (MOs). In the present study the relationship between the scintigraphic and CMR characteristics of MOs after acute myocardial infarction (MI) was examined. METHODS AND RESULTS: The 14 patients (age 69±8 years, 11 males) underwent 201-Tl/99m-Tc PYP SPECT 7±3 days, initial CMR 16±12 days, and follow-up CMR 193±20 days after a reperfused first acute MI. Each image was analyzed using a 17-segment model. Segmental extent of delayed enhancement (DE), wall motion (WM) and degree of 201-Tl uptake were scored in 238 segments. Of 91 MI segments, MO was recognized in 22 (25%) segments on CMR. WM was significantly better in proportion to 201-Tl uptake (P=0.01) in MO segments. All 8 MO segments with WM improvement at follow-up had 99m-Tc PYP uptake, although only 3 (21%) of 14 MO segments that did not show WM improvement at follow-up had 99m-Tc PYP uptake (P=0.001). CONCLUSIONS: 99m-Tc PYP and 201-Tl scintigraphy have the potential to predict WM status and improvement of the MO region after reperfused acute MI.