Background-Myocyte necrosis as a result of elective percutaneous coronary intervention (PCI) occurs in approximately one third of cases and is associated with subsequent cardiovascular events. This study assessed the ability of remote ischemic preconditioning (IPC) to attenuate cardiac troponin I (cTnI) release after elective PCI. Methods and Results-Two hundred forty-two consecutive patients undergoing elective PCI with undetectable preprocedural cTnI were recruited. Subjects were randomized to receive remote IPC (induced by three 5-minute inflations of a blood pressure cuff to 200 mm Hg around the upper arm, followed by 5-minute intervals of reperfusion) or control (an uninflated cuff around the arm) before arrival in the catheter laboratory. The primary outcome was cTnI at 24 hours after PCI. Secondary outcomes included renal dysfunction and major adverse cardiac and cerebral event rate at 6 months. The median cTnI at 24 hours after PCI was lower in the remote IPC compared with the control group (0.06 versus 0.16 ng/mL; Pϭ0.040). After remote IPC, cTnI was Ͻ0.04 ng/mL in 44 patients (42%) compared with 24 in the control group (24%; Pϭ0.01). Subjects who received remote IPC experienced less chest discomfort (Pϭ0.0006) and ECG ST-segment deviation (Pϭ0.005) than control subjects. At 6 months, the major adverse cardiac and cerebral event rate was lower in the remote IPC group (4 versus 13 events; Pϭ0.018). Conclusion-Remote IPC reduces ischemic chest discomfort during PCI, attenuates procedure-related cTnI release, and appears to reduce subsequent cardiovascular events. (Circulation. 2009;119:820-827.)

Background-Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted postprandially that promotes myocardial glucose uptake. The active amide GLP-1 (7-36) is degraded by the enzyme DPP-4, and drugs that inhibit this enzyme (such as sitagliptin) have been introduced to treat type 2 diabetes. We assessed the hypothesis that increasing the plasma concentration of GLP-1 by DPP-4 inhibition would protect the heart from ischemic left ventricular (LV) dysfunction during dobutamine stress echocardiography in patients with coronary artery disease. Methods and Results-Fourteen patients with coronary artery disease and preserved LV function awaiting revascularization were studied. After either a single dose of 100 mg sitagliptin or placebo, 75 g of glucose was given orally to promote GLP-1 secretion and dobutamine stress echocardiography was conducted with tissue Doppler imaging at rest, peak stress, and 30 minutes. After sitagliptin, plasma GLP-1 (7-36) was increased at peak stress (16.5Ϯ10.7 versus 9.7Ϯ8.7 pg/mL; Pϭ0.003) and in recovery (12.4Ϯ5.5 versus 9.0Ϯ5.5 pg/mL; Pϭ0.01), and the LV response to stress was enhanced (ejection fraction, 72.6Ϯ7.

Patients with AF have lower regional voltage, increased proportion of low voltage, slowed conduction, and increased proportion of complex signals compared to controls. Many of these changes are more pronounced in persistent AF patients, suggesting there may be a progressive nature to the changes. Differences occurred in the absence of structural heart disease. These substrate abnormalities provide further insight into the progressive nature of atrial remodeling and the mechanisms involved in maintenance of AF.