The Association Between a Second Course of Cardiac Rehabilitation and Cardiovascular Outcomes Following Repeat Percutaneous Coronary Intervention Events.

PURPOSE: Survivors of coronary artery disease (CAD) events are at risk for repeat events. Although evidence supports cardiac rehabilitation (CR) after an initial CAD event, it is unclear whether a repeat course of CR (CR × 2) is beneficial after a recurrent CAD event. The purpose of this study was to determine the association of CR × 2 with clinical outcomes in persons undergoing repeat percutaneous coronary intervention (PCI). METHODS: We assessed the prevalence of CR × 2 and its impact on cardiovascular outcomes in individuals who experienced a repeat PCI at the Mayo Clinic hospitals between January 1, 1998, and December 31, 2013. Landmark analyses were used to calculate unadjusted and propensity score adjusted mortality rates and cardiovascular (CV) events rates for patients who underwent CR × 2 compared with those who did not. RESULTS: Among 240 individuals who had a repeat PCI and who had participated in CR after their first PCI, 97 (40%) participated in CR × 2. Outcomes were assessed for a mean follow-up time of 7.8 yr (IQR 7.1-9.0 yr). Propensity score-based inverse probability weighting analysis revealed that CR × 2 was associated with significantly lower target lesion revascularization (HR = 0.47: 95% CI, 0.26-0.86; P = .014), lower combined end point of CV death, myocardial infarction, and target lesion revascularization (HR = 0.57: 95% CI, 0.36-0.89; P = .014), and lower CV hospitalization (HR = 0.60; 95% CI, 0.43-0.84; P = .003). CONCLUSION: A second course of CR following repeat PCI is associated with a lower risk of adverse clinical outcomes. These findings support current policies that allow for repeat courses of CR following recurrent CV events.

Supravalvular arrhythmia: identifying and ablating the substrate.

Supravalvar ablation has now been well documented to be the ideal mode for ablating specific forms of ventricular tachycardia, atrial tachycardia, and accessory pathways. A studied appreciation of the anatomy of the supravalvar region is a prerequisite for electrophysiologists to safely and effectively approach these arrhythmias. In addition, the consistent ability to correlate the recorded electrograms with fluoroscopic anatomy and intracardiac ultrasound images enhances the chance of successful elimination of supravalvar arrhythmias.

Homer modulates NFAT-dependent signaling during muscle differentiation.

While changes in intracellular calcium are well known to influence muscle contraction through excitation contraction coupling, little is understood of the calcium signaling events regulating gene expression through the calcineurin/NFAT pathway in muscle. Here, we demonstrate that Ca(+2) released via the inositol trisphosphate receptor (IP3R) increases nuclear entry of NFAT in undifferentiated skeletal myoblasts, but the IP3R Ca(+2) pool in differentiated myotubes promotes nuclear exit of NFAT despite a comparable quantitative change in [Ca(+2)]i. In contrast, Ca(+2) released via ryanodine receptors (RYR) increases NFAT nuclear entry in myotubes. The scaffolding protein Homer, known to interact with both IP3R and RYR, is expressed as part of the myogenic differentiation program and enhances NFAT-dependent signaling by increasing RYR Ca(+2) release. These results demonstrate that differentiated skeletal myotubes employ discrete pools of intracellular calcium to restrain (IP3R pool) or activate (RYR pool) NFAT-dependent signaling, in a manner distinct from undifferentiated myoblasts. The selective expression of Homer proteins contributes to these differentiation-dependent features of calcium signaling.