Rat carotid artery dilation by PTCA balloon catheter induces neointima formation in presence of IEL rupture

The best animal angioplasty model is the porcine model, which is expensive and not available in all laboratories. The aim of this study was to describe a new rat model of angioplasty. An injury was induced with the use of a standard percutaneous transluminal coronary angioplasty (PTCA) 1.5-mm balloon catheter. The neointimal tissue, arterial dimensions, and the injury index were assessed following angioplasty. Ki-67 expression was detected to evaluate cell turnover after balloon angioplasty. In contrast with the standard Clowes model, a significant neointimal formation was detected only in the presence of ruptured internal elastic lamina (IEL). A positive correlation between the percentage of ruptured IEL and the amount of neointimal tissue was also demonstrated. The percentage of IEL fracture correlates with the proliferation index by anti-Ki-67 immunolabeling 7 and 14 days after the angioplasty. Significant arterial negative remodeling was observed following PTCA balloon dilation. In conclusion, our inexpensive animal model of restenosis after angioplasty may have great relevance toward a better understanding of the mechanisms and toward assessment of new therapeutical strategies for this phenomenon

Long-term Outcomes of Stand-Alone Maze IV for Persistent or Long-standing Persistent Atrial Fibrillation

Background: The study sought to assess the long-term outcomes of the stand-alone Cox-Maze IV procedure in symptomatic patients with refractory, persistent, or long-standing persistent atrial fibrillation (AF). Methods: Fifty-nine consecutive patients (mean age 52 ± 10.5 years, previous catheter ablation 80%, left ventricular ejection fraction 55% ± 3.4%, median left atrial volume index 41 [interquartile range, 34-47] mL/m2) with symptomatic, refractory, persistent (56%), or longstanding persistent (44%) AF, underwent stand-alone Cox-Maze IV procedure. Biatrial ablations were performed with bipolar radiofrequency and cryoenergy. Left atrial appendage was excluded in 56 of 59 (95%) patients. Results: No hospital deaths occurred and 1 (1.7%) patient required postoperative pacemaker implantation. Follow-up was 97% complete (median 5.8 [interquartile range, 3.92-7.11] years). The overall survival at 7 years was 97% ± 2.3%. The 7-year cumulative incidence function of AF recurrence and of AF recurrence off class I or III antiarrhythmic drugs (AADs), with death as competing risk, was 14.2% ± 5.6% (95% confidence interval [CI], 5.5%-26.8%) and 26.5% ± 6.9% (95% CI, 14.2%-40.4%), respectively. Multivariate analysis identified the duration of AF as the only predictor of AF recurrence (hazard ratio, 1.01; 95% CI, 1.01-1.02; P < .001). At 7 years, the proportion of patients in sinus rhythm was 84%, of whom 74% were off class I or III AADs. At the last follow-up, 75% of patients were in European Heart Rhythm Association functional class I, no stroke and thromboembolic events were documented, and 70% of patients were off anticoagulation therapy. Left ventricular ejection fraction improved from 53% ± 3.4% at baseline to 59% ± 3.4% at follow-up (P = .003). Conclusions: This study confirmed the safety and efficacy in the long term (7 years) of the stand-alone Cox-Maze IV surgical procedure for persistent or long-standing persistent AF. Indeed, more than 70% of the patients were in sinus rhythm off class I or III AADs and off oral anticoagulation

Long-term results of thoracoscopic ablation of paroxysmal atrial fibrillation: is the glass half full or half empty?

OBJECTIVES: Previous series showed the outcomes of thoracoscopic ablation of stand-alone symptomatic paroxysmal atrial fibrillation (AF) for up to 7 years of follow-up. The goal of this study was to assess the long-term durability of surgical pulmonary vein isolation (PVI) beyond 7 years. METHODS: Fifty consecutive patients {mean age 55 [standard deviation (SD): 11.2] years, previous catheter ablation in 56%, left ventricular ejection fraction 60% (SD: 4.6), left atrium volume 65 ml (SD: 17)} with stand-alone symptomatic paroxysmal AF underwent PVI through bilateral thoracoscopy ablation between 2005 and 2014. The CHA(2)DS(2)-VASc score was >= 2 in 12 patients (24%). RESULTS: No hospital deaths occurred. At hospital discharge all patients but 1 (2%) were in sinus rhythm (SR). Follow-up was 100% complete [mean 8.4 years (SD: 2.3), max 15]. The 8-year cumulative incidence function of AF recurrence, with death as a competing risk, on or off class I/III antiarrhythmic drugs (AADs)/electrocardioversion/re-transcatheter ablation (TCA) was 20% (SD: 5; 95% confidence interval: 10, 32); and off class I/III AADs/electrocardioversion/re-TCA was 52% (SD: 7; 95% confidence interval: 0.83, 8.02). At 8 years, the predicted prevalence of patients in SR was 87% and 53% were off class I/III AADs/electrocardioversion/re-TCA. The recurrent arrhythmia was AF in all patients except 2, who had atypical atrial flutter (4%). No predictors of AF recurrence were identified. At the last follow-up, 76% of the patients showed European Heart Rhythm Association class I. No strokes or thromboembolic events were documented and 76% of the subjects were off anticoagulation therapy. CONCLUSIONS: Despite a considerable AF recurrence rate, our single-centre, long-term outcome of surgical PVI showed encouraging data, with the majority of patients remaining in SR, although many of them were on antiarrhythmic therapy