Integrative Assessment of Cardiopulmonary Fitness Using Cardiopulmonary Exercise Test With Supine Bicycle Echocardiography in Patients Presenting Dyspnea.

BACKGROUND: Cardiopulmonary exercise test (CPET) with supine bicycle echocardiography (SBE) enables comprehensive physiologic assessment during exercise. We characterized cardiopulmonary fitness by integrating CPET-SBE parameters and evaluated its prognostic value in patients presenting with dyspnea. METHODS AND RESULTS: We retrospectively reviewed 473 consecutive patients who underwent CPET-SBE for dyspnea evaluation. A dimensionality reduction process was applied, transforming 24 clinical and CPET-SBE parameters into a 2-dimensional feature map, followed by patient clustering based on the data distribution. Clinical and exercise features were compared among the clusters in addition to the 5-year risk of clinical outcome (a composite of cardiovascular death and heart failure hospitalization). Maximum exercise effort (R >1) was achieved in 95% of cases. Through dimensionality reduction, 3 patient clusters were derived: Group 1 (n=157), 2 (n=104), and 3 (n=212). Median age and female proportion increased from Group 1 to 2, and 3, although resting echocardiography parameters showed no significant abnormalities among the groups. There was a worsening trend in the exercise response from Group 1 to 2 and 3, including left ventricular diastolic function, oxygen consumption, and ventilatory efficiency. During follow-up (median 6.0 [1.6-10.4] years), clinical outcome increased from Group 1 to 2 and 3 (5-year rate 3.7% versus 7.0% versus 13.0%, respectively; log-rank P=0.02), with higher risk in Group 2 (hazard ratio, 1.94 [95% CI, 0.52-7.22]) and Group 3 (3.92 [1.34-11.42]) compared with Group 1. CONCLUSIONS: Comprehensive evaluation using CPET-SBE can reveal distinct characteristics of cardiopulmonary fitness in patients presenting with dyspnea, potentially enhancing outcome prediction.

Long-term Outcome of Cryoballoon Ablation in Korean Patients With Atrial Fibrillation: Real-World Experience From the Cryo Global Registry.

BACKGROUND AND OBJECTIVES: Atrial fibrillation (AF), the most common atrial arrhythmia (AA), is an increasing healthcare burden in Korea. The objective of this sub-analysis of the Cryo Global Registry was to evaluate long-term efficacy, symptom burden, quality of life (QoL), and healthcare utilization outcomes and factors associated with AA recurrence in Korean patients treated with cryoballoon ablation (CBA). METHODS: Patients were treated and followed up according to local standard-of-care in 3 Korean hospitals. Kaplan-Meier estimates were used in analyzing (1) efficacy defined as freedom from ≥30 second recurrence of AA at 24 months, (2) healthcare utilization, and (3) predictors of 24-month AA recurrence. Patient-reported QoL (using European Quality of Life-5 Dimensions-3 Levels) and predefined AF-related symptoms were assessed at baseline and 24-month follow-up. RESULTS: Efficacy was 71.9% in paroxysmal AF (PAF) and 49.3% in persistent AF (PsAF) patients (p<0.01). A larger left atrial diameter (LAD), an increased time from AF diagnosis to CBA, and PsAF were independent predictors of AA recurrence. The percentage of patients with no AF symptoms significantly increased from baseline (24.5%) to 24-month (89.5%) follow-up (p<0.01). Improvement in QoL from baseline to 24 months was not statistically different between AF cohorts. PAF patients experienced greater freedom from repeat ablations (93.9% vs. 81.4%) and cardiovascular hospitalizations (91.3% vs. 72.5%, p<0.001 for both). CONCLUSIONS: In alignment with global outcomes, CBA is an effective treatment for AF in the Korean population, with patients possessing a large LAD and not receiving ablation soon after diagnosis being the most at risk for AA recurrence. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02752737.