Guddeti, Raviteja R

Background The study compared downstream coronary and conduit disease progression in the left anterior descending coronary artery treated with coronary artery bypass grafting using the left internal mammary artery ( LIMA ) versus percutaneous coronary intervention with bare metal stent ( BMS ) or drug eluting stent ( DES ). Methods and Results A total of 12 301 consecutive patients underwent isolated primary coronary revascularization, of which 2386 met our inclusion criteria (Percutaneous coronary intervention, n=1450; coronary artery bypass grafting, n=936). Propensity score analysis matched 628 patients, of which 468 were treated to the left anterior descending with coronary artery bypass grafting with LIMA (n=314), percutaneous coronary intervention with BMS (n=94), and DES (n=60). Coronary angiograms were analyzed by quantitative coronary angiography ( QCA ; n=433). Cumulative downstream coronary and conduit disease progression were estimated by Kaplan–Meier method and effect of treatment type by Cox proportional hazard models. Patients treated with LIMA had significantly lower risk of downstream coronary disease progression at follow‐up angiogram compared with BMS and DES (hazard ratio [ HR ] [95% CI ], 0.34; [0.20–0.59]; P =0.0002; and HR [95% CI ], 0.39; [0.20–0.79]; P =0.01, respectively). LIMA was associated with a lower risk of conduit disease progression compared to BMS and DES ( HR [95% CI ], 0.18; [0.12–0.28]; P <0.001; and HR [95% CI ], 0.27; [0.16–0.46]; P <0.001, respectively). BMS was associated with higher HR for downstream coronary and conduit disease progression compared with DES , but the difference did not reach statistical significance ( HR [95% CI], 1.13; [0.57–2.36]; P =0.73; and HR [95% CI ], 1.46; [0.88–2.50]; P =0.14, respectively). Conclusions LIMA grafting to left anterior descending is associated with significantly lower risk of downstream coronary and conduit disease progression compared to percutaneous coronary intervention with BMS and DES .

Background The mechanisms of atrial fibrillation (AF) are highly divergent. The prevalence of AF increases significantly with age, and underling mechanisms might vary with age. Endothelial dysfunction may be associated with AF and atrial arrhythmia recurrence after catheter ablation. We tested the hypothesis that the impact of endothelial dysfunction on arrhythmia recurrence following catheter ablation is age dependent. Methods and Results This study enrolled 92 participants with AF undergoing catheter ablation. Endothelial function was assessed by peripheral arterial tonometry before ablation, and the natural logarithmic transformation of reactive hyperemia index was calculated. Endothelial dysfunction was defined as a natural logarithmic transformation of reactive hyperemia index <0.618 (median). Participants were followed for atrial tachycardia, flutter, and fibrillation recurrence for a median of 14 months. The mean age was 57±10 years. There was significant interaction between age and endothelial dysfunction in association with recurrence of AF ( P =0.029) and any atrial arrhythmia ( P =0.015), and the risk associated with endothelial dysfunction for arrhythmia recurrence was higher in younger versus older participants. Participants were divided into 2 age groups at a threshold of 60 years. Among participants aged ≤60 years, multivariate Cox proportional hazards analysis revealed the independent association between endothelial dysfunction and increased risk of arrhythmia recurrence (hazard ratio for AF 4.18 [95% CI 1.33–15.82], P =0.014, and for any atrial arrhythmia 3.62 [95% CI 1.29–11.81], P =0.014). Kaplan–Meier analysis showed that participants with endothelial dysfunction had significantly higher rates of recurrence of AF ( P =0.01) and any atrial arrhythmia ( P =0.002). Conclusions The risk associated with endothelial dysfunction for arrhythmia recurrence following catheter ablation was age dependent and was higher in younger participants.

Background— Spontaneous coronary artery dissection (SCAD) is an increasingly recognized nonatherosclerotic cause of acute coronary syndrome. The angiographic characteristics of SCAD are largely undetermined. The goal of this study was to determine the prevalence of coronary tortuosity in SCAD and whether it may be implicated in the disease. Methods and Results— Patients with confirmed SCAD (n=246; 45.3±8.9 years; 96% women) and 313 control patients without SCAD or coronary artery disease who underwent coronary angiography were included in this case–control study. Angiograms were reviewed for coronary tortuosity and assigned a tortuosity score. Tortuosity was common in patients presenting with their first SCAD event (78% versus 17% in controls; P <0.0001; tortuosity score, 4.41±1.73 versus 2.33±1.49 in controls; P <0.0001) despite a low prevalence of hypertension (34%). Recurrent SCAD (n=40) occurred within segments of tortuosity in 80% of cases. Severe tortuosity (≥2 consecutive curvatures ≥180°) was associated with a higher risk of recurrent SCAD (hazard ratio, 3.29; 95% confidence interval, 0.99–8.29; P =0.05). Tortuosity score >5 was associated with a trend toward higher risk of recurrent SCAD ( P =0.16). Prespecified angiographic markers of tortuosity including corkscrew appearance and multivessel symmetrical tortuosity were associated with extracoronary vasculopathy including fibromuscular dysplasia ( P <0.05 for both). Conclusions— Coronary artery tortuosity is highly prevalent in the SCAD population and is associated with recurrent SCAD. Recurrent SCAD most often occurs within segments of tortuosity. Angiographic features of SCAD are associated with extracoronary vasculopathy, including fibromuscular dysplasia. These findings suggest that coronary tortuosity may serve as a marker or potential mechanism for SCAD.