Background Catheter ablation (CA) is a promising option in most patients with refractory atrial fibrillation (AF). However, data on over 5 years' outcomes with larger numbers in hypertrophic cardiomyopathy (HCM) patients with AF have not been reported. We assessed the outcome of 120 HCM patients following CA compared with a non‐CA group and general patients without AF matched by HCM type with a 61.9 ± 31.6‐month follow‐up. Methods and Results A total of 120 patients (age 61 ± 9.8 years, female n = 43, 35.8%) with paroxysmal AF (n = 60, 50%) and persistent AF (n = 60, 50%) were enrolled. Of the 120 patients, 48 (40%) required redo procedures, and 82 (68.3%) were in sinus rhythm at the last evaluation. The composite clinical events rate following the initial CA was lower than that in the non‐CA group (P = .023) and was also comparable to that in general patients without AF matched by HCM type (P = .729). Female (HR 2.358, 95% CI, 1.151‐4.831; P = .019), NYHA functional class III‐IV (HR 2.422, 95% CI, 1.032‐5.685; P = .042) and left atrial diameter ≥50 mm (HR 3.319, 95% CI, 1.469‐7.499; P = .004) were predictors of AF recurrence after multiple procedures. Conclusions CA was successful in restoring long‐term sinus rhythm and improving symptomatic status in most HCM patients with refractory AF especially for those patients with small atrial size and mild symptoms. In addition, CA may contribute to the prevention of major clinical adverse events in the long‐term clinical course.

IntroductionIn coronary bifurcation lesions treated with percutaneous coronary intervention (PCI) using a 1-stent strategy, the occurrence of side branch (SB) compromise may lead to long-term myocardial ischemia in the SB territory. Murray law–based quantitative flow ratio (μQFR) is a novel angiography-based approach estimating fractional flow reserve from a single angiographic view, and thus is more feasible to assess SB compromise in routine practice. However, its association with long-term SB coronary blood flow remains unknown.MethodsA total of 146 patients with 313 non-left main bifurcation lesions receiving 1-stent strategy with drug-eluting stents was included in this retrospective study. These lesions had post-procedural Thrombolysis in Myocardial Infarction (TIMI) flow grade 3 in SBs, and documented angiographic images of index procedure and 6- to 24-month angiographic follow-up. Post-procedural SB μQFR was calculated. Long-term SB coronary blood flow was quantified with the TIMI grading system using angiograms acquired at angiographic follow-up.ResultsAt follow-up, 8 (2.6%), 16 (5.1%), 61 (19.5%), and 228 (72.8%) SBs had a TIMI flow grade of 0, 1, 2, and 3, respectively. The incidences of long-term SB TIMI flow grade ≤1 and ≤2 both tended to decrease across the tertiles of post-procedural SB μQFR. The receiver operating characteristic curve analyses indicated the post-procedural SB μQFR ≤0.77 was the optimal cut-off value to identify long-term SB TIMI flow grade ≤1 (specificity, 37.50%; sensitivity, 87.20%; area under the curve, 0.6673; P = 0.0064), and it was independently associated with 2.57-fold increased risk (adjusted OR, 2.57; 95% CI, 1.02–7.25; P = 0.045) in long-term SB TIMI flow grade ≤1 after adjustment.DiscussionPost-procedural SB μQFR was independently associated with increased risk in impaired SB TIMI flow at long-term follow-up. Further investigations should focus on whether PCI optimization based on μQFR may contribute to improve SB flow in the long term.