Right atrial conduction time for predicting coexistent typical atrial flutter in patients with paroxysmal atrial fibrillation.

INTRODUCTION: Screening of coexistent typical atrial flutter (AFL) in patients with atrial fibrillation (AF) is sometimes challenging. This study investigated whether a prolonged right atrial conduction time (RACT) estimated by tissue Doppler imaging (TDI) predicts patients with concomitant AFL and AF. METHODS AND RESULTS: We retrospectively analyzed 398 patients (mean age: 61.6 years, 73.4% men) undergoing catheter ablation of paroxysmal AF. The patients were classified into two groups according to whether they had evidence of AFL (N = 122, 30.7%) determined by a clinical observation (N = 68), induction during procedures (N = 33), or AFL recurrence after procedures (N = 21) or not (N = 276, 69.3%). The preoperative RACT, defined as a longer duration between the onset of the P-wave and peak A'-wave on the right atrial lateral wall or septal wall, and total atrial conduction time (TACT), defined as the same time duration on the left atrial lateral wall, were evaluated in all patients. Patients with evidence of AFL had a significantly longer RACT than those without AFL (p < .001). A multiple logistic regression and receiver operator characteristics curve analysis revealed the ratio of the RACT and TACT (RACT/TACT) was the independent and most superior accurate cofounder for predicting evidence of AFL (area under the curve: 0.867). When adding a discriminator of an RACT/TACT ≧ 93% into the conventional screening, 98.4% of the patients with evidence of AFL were estimated to be treated during the initial procedures. CONCLUSION: The estimated RACT/TACT using the TDI may be useful for predicting patients with concomitant AFL in patients with AF.

A novel optimized adaptive servo-ventilation setting for a patient with severe heart failure based on the echocardiogram: a case report.

Background: Adaptive servo-ventilation (ASV) is a non-invasive positive-pressure ventilation therapy considered beneficial for treating heart failure (HF) in patients with central sleep apnoea. However, to the best of our knowledge, there is no evidence indicating that this therapy increases the mortality in HF patients. We hypothesized that ASV settings are important for HF patients with reduced ejection fraction. Therefore, to determine the suitable ASV setting for such patients, we optimized these settings to improve the left ventricular (LV) output during the therapy. Case summary: We present a case of HF caused by dilated cardiomyopathy in a 45-year-old man. He was hospitalized due to HF; his LV ejection fraction was ∼20%, and haemodynamics analysis revealed his HF grade was Forrester subset IV. During hospitalization, he was diagnosed with sleep apnoea; therefore, we induced ASV with our optimized setting using an echocardiogram evaluating stroke volume (SV). Using this method, we could determine the appropriate setting that increased his SV and improved his apnoea-hypopnoea index. At the 5th-year follow-up, he had no dyspnoea on effort (New York Heart Association Functional Classification I). He continued using the ASV with good adherence, and no hospitalization for ventricular arrhythmia and HF was reported. Discussion: Our ASV optimized setting showed beneficial effects in an HF patient with reduced ejection fraction. This method improved the patient's SV and apnoea-hypopnoea index, indicating that this novel method should be considered for HF patients with reduced ejection fraction.