Pathophysiology of exercise heart rate recovery: a comprehensive analysis.

Expanded use of exercise heart rate recovery (HRR) has renewed interest in the pathophysiology of heart rate control. This study uses basic physiologic principles to construct a unique model capable of describing the full time course of sympathetic and parasympathetic activity during HRR. The model is tested in a new study of 22 diverse subjects undergoing both maximal and submaximal treadmill exercise.

Prognostic value of 12-lead electrocardiogram and peak troponin I level after vascular surgery.

Objective: The aim of this investigation was to determine if the presence of ischemic electrocardiographic (ECG) changes in patients undergoing vascular surgery provides incremental prognostic information about the long-term risk of death compared with a single peak troponin level within 48 hours after surgery.

Methods: This was a retrospective analysis of 337 patients undergoing moderate-risk to high-risk vascular surgery at our institution whose ECG and biomarker data were complete. Peak cardiac troponin (cTn) I values that exceeded the upper reference limit (URL) were categorized as low-positive (+), at or exceeding the URL but less than three times the URL, or high-positive (+), at or exceeding three times the URL.

Preoperative coronary artery revascularization and long-term outcomes following abdominal aortic vascular surgery in patients with abnormal myocardial perfusion scans: a subgroup analysis of the coronary artery revascularization prophylaxis trial.

Background: Abdominal aortic operations have the highest perioperative cardiac risk. To test the impact of preoperative coronary artery revascularization (PR) in this high-risk subset, a post hoc analysis was performed in patients undergoing aortic surgery within the Coronary Artery Revascularization Prophylaxis (CARP) trial.

Methods: The study cohort was a subset of 109 CARP patients with myocardial ischemia on nuclear imaging randomized to a strategy of PR (N = 52) or no PR (N = 57) before their scheduled abdominal aortic vascular operation.